WorldWideScience

Sample records for cold-season downburst event

  1. Transient Thunderstorm Downbursts and Their Effects on Wind Turbines

    Directory of Open Access Journals (Sweden)

    Hieu H. Nguyen

    2014-10-01

    Full Text Available The International Electrotechnical Commission (IEC Standard 61400-1 for the design of wind turbines does not explicitly address site-specific conditions associated with anomalous atmospheric events or conditions. Examples of off-standard atmospheric conditions include thunderstorm downbursts, hurricanes, tornadoes, low-level jets, etc. The simulation of thunderstorm downbursts and associated loads on a utility-scale wind turbine is the focus of this study. Since the problem has not received sufficient attention, especially in terms of design, we thus focus in this paper on practical aspects. A wind field model that incorporates component non-turbulent and turbulent parts is described and employed in inflow simulations. The non-turbulent part is based on an available analytical model with some modifications, while the turbulent part is simulated as a stochastic process using standard turbulence power spectral density functions and coherence functions whose defining parameters are related to the downburst characteristics such as the storm translation velocity. Available information on recorded downbursts is used to define two storm scenarios that are studied. Rotor loads are generated using stochastic simulation of the aeroelastic response of a model of a utility-scale 5-MW turbine. An illustrative single storm simulation and the associated turbine response are used to discuss load characteristics and to highlight storm-related and environmental parameters of interest. Extensive simulations for two downbursts are then conducted while varying the storm’s location and track relative to the turbine. Results suggest that wind turbine yaw and pitch control systems clearly influence overall system response. Results also highlight the important effects of both the turbulence as well as the downburst mean wind profiles on turbine extreme loads.

  2. Leonardo da Vinci and the Downburst.

    Science.gov (United States)

    Gedzelman, Stanley David

    1990-05-01

    Evidence from the drawings, experiments, and writings of Leonardo da Vinci are presented to demonstrate that da Vinci recognized and, possibly, discovered the downburst and understood its associated airflow. Other early references to vortex flows resembling downbursts are mentioned.

  3. Doppler radar observation, CG lightning activity and aerial survey of a multiple downburst in southern Germany on 23 March 2001

    OpenAIRE

    Dotzek, Nikolai; Lang, Peter; Hagen, Martin; Fehr, Thorsten; Hellmiss, Werner

    2007-01-01

    Two downburst events from one thunderstorm are investigated, which occurred on 23 March 2001, in Germany's climatologic annual minimum of downburst activity. Observations by two Doppler radars are combined with hail reports, ground lightning detection and an aerial survey conducted after the event. The downburst-producing storm had formed at a synoptic convergence line within the warm sector of a cyclone. It had a remarkably high propagation speed of up to 31 m s−1 corresponding to the mid...

  4. MCS precipitation and downburst intensity response to increased aerosol concentrations

    Science.gov (United States)

    Clavner, M.; Cotton, W. R.; van den Heever, S. C.

    2015-12-01

    Mesoscale convective systems (MCSs) are important contributors to rainfall in the High Plains of the United States as well as producers of severe weather such as hail, tornados and straight-line wind events known as derechos. Past studies have shown that changes in aerosol concentrations serving as cloud condensation nuclei (CCN) alter the MCS hydrometeor characteristics which in turn modify precipitation yield, downdraft velocity, cold-pool strength, storm propagation and the potential for severe weather to occur. In this study, the sensitivity of MCS precipitation characteristics and convective downburst velocities associated with a derecho to changes in CCN concentrations were examined by simulating a case study using the Regional Atmospheric Modeling System (RAMS). The case study of the 8 May 2009 "Super-Derecho" MCS was chosen since it produced a swath of widespread wind damage in association with an embedded large-scale bow echo, over a broad region from the High Plains of western Kansas to the foothills of the Appalachians. The sensitivity of the storm to changes in CCN concentrations was examined by conducting a set of three simulations which differed in the initial aerosol concentration based on output from the 3D chemical transport model, GEOS-Chem. Results from this study indicate that while increasing CCN concentrations led to an increase in precipitation rates, the changes to the derecho strength were not linear. A moderate increase in aerosol concentration reduced the derecho strength, while the simulation with the highest aerosol concentrations increased the derecho intensity. These changes are attributed to the impact of enhanced CCN concentration on the production of convective downbursts. An analysis of aerosol loading impacts on these MCS features will be presented.

  5. Two cold-season derechoes in Europe

    Science.gov (United States)

    Gatzen, Christoph; Púčik, Tomas; Ryva, David

    2011-06-01

    In this study, we apply for the first time the definition of a derecho (Johns and Hirt, 1987) to European cold-season convective storm systems. These occurred on 18 January 2007 and 1 March 2008, respectively, and they are shown to fulfill the criteria of a derecho. Damaging winds were reported over a distance of 1500 km and locally reached F3 intensity. Synoptic analysis for the events reveal strongly forced situations that have been described for cold-season derechoes in the United States. A comparison of swaths of damaging winds, radar structures, detected lightning, cold pool development, and cloud-top temperatures indicates that both derechoes formed along cold fronts that were affected by strong quasi-geostrophic forcing. It seems that the overlap of the cold front position with the strong differential cyclonic vorticity advection at the cyclonic flank of mid-level jet streaks favoured intense convection and high winds. The movement and path width of the two derechoes seemed to be related to this overlap. The wind gust intensity that was also different for both events is discussed and could be related to the component of the mid-level winds perpendicular to the gust fronts.

  6. Cold-Season Tornadoes: Climatological, Meteorological, and Social Perspectives

    Science.gov (United States)

    Childs, Samuel J.

    the variance in counts. A second perspective focuses on meteorological environments that characterize NDJF tornadoes through use of the NCEP/NCAR Reanalysis. Upon comparing the most tornadic and least tornadic cold seasons, it is found that active seasons are characterized by a large trough in the western U.S.; warm and moist conditions across the Southeast, likely due to an enhanced low-level jet transport from the western Gulf of Mexico; and enhanced 1000-500-hPa wind speed shear. The third perspective addressed in this thesis is that of social science. A case study of four tornado events from November 2016-February 2017, in which a post-event survey is disseminated to NWS meteorologists, broadcast meteorologists, and emergency managers, is carried out to assess strategies and barriers professionals face when communicating cold-season tornado risk and warnings to their respective communities. The survey also aims to shed light on the perceived levels of human preparedness, vulnerability, and resiliency from the professional's point of view. In addition to unique, case-specific challenges, the professionals expressed major barriers to communication due to inconsistency of messages and graphics, and an inability to give the public information on fine enough temporal and spatial scales. Each decision-making sector noted a high local vulnerability to tornadoes in general, mostly brought on by lack of education and/or resources. However, most professionals perceive their communities to be aware of cold-season tornado risk and thus adequately prepared and resilient when they occur. The survey results also confirm the desire and need for better collaboration among professionals, and with social scientists, in order to adequately educate and warn all sectors of society from tornado risk, especially those during times of year they are not typically expected. Harnessing all three perspectives presented in this study provides a much deeper understanding of NDJF tornadoes and

  7. Cold season emissions dominate the Arctic tundra methane budget

    Science.gov (United States)

    Zona, Donatella; Gioli, Beniamino; Commane, Róisín; Lindaas, Jakob; Wofsy, Steven C.; Miller, Charles E.; Dinardo, Steven J.; Dengel, Sigrid; Sweeney, Colm; Karion, Anna; Chang, Rachel Y.-W.; Henderson, John M.; Murphy, Patrick C.; Goodrich, Jordan P.; Moreaux, Virginie; Liljedahl, Anna; Watts, Jennifer D.; Kimball, John S.; Lipson, David A.; Oechel, Walter C.

    2016-01-01

    Arctic terrestrial ecosystems are major global sources of methane (CH4); hence, it is important to understand the seasonal and climatic controls on CH4 emissions from these systems. Here, we report year-round CH4 emissions from Alaskan Arctic tundra eddy flux sites and regional fluxes derived from aircraft data. We find that emissions during the cold season (September to May) account for ≥50% of the annual CH4 flux, with the highest emissions from noninundated upland tundra. A major fraction of cold season emissions occur during the "zero curtain" period, when subsurface soil temperatures are poised near 0 °C. The zero curtain may persist longer than the growing season, and CH4 emissions are enhanced when the duration is extended by a deep thawed layer as can occur with thick snow cover. Regional scale fluxes of CH4 derived from aircraft data demonstrate the large spatial extent of late season CH4 emissions. Scaled to the circumpolar Arctic, cold season fluxes from tundra total 12 ± 5 (95% confidence interval) Tg CH4 y-1, ∼25% of global emissions from extratropical wetlands, or ∼6% of total global wetland methane emissions. The dominance of late-season emissions, sensitivity to soil environmental conditions, and importance of dry tundra are not currently simulated in most global climate models. Because Arctic warming disproportionally impacts the cold season, our results suggest that higher cold-season CH4 emissions will result from observed and predicted increases in snow thickness, active layer depth, and soil temperature, representing important positive feedbacks on climate warming.

  8. Medieval Irish chronicles reveal persistent volcanic forcing of severe winter cold events, 431–1649 CE

    International Nuclear Information System (INIS)

    Ludlow, Francis; Stine, Alexander R; Leahy, Paul; Kiely, Gerard; Murphy, Enda; Mayewski, Paul A; Taylor, David; Killen, James; Hennessy, Mark; Baillie, Michael G L

    2013-01-01

    Explosive volcanism resulting in stratospheric injection of sulfate aerosol is a major driver of regional to global climatic variability on interannual and longer timescales. However, much of our knowledge of the climatic impact of volcanism derives from the limited number of eruptions that have occurred in the modern period during which meteorological instrumental records are available. We present a uniquely long historical record of severe short-term cold events from Irish chronicles, 431–1649 CE, and test the association between cold event occurrence and explosive volcanism. Thirty eight (79%) of 48 volcanic events identified in the sulfate deposition record of the Greenland Ice Sheet Project 2 ice-core correspond to 37 (54%) of 69 cold events in this 1219 year period. We show this association to be statistically significant at the 99.7% confidence level, revealing both the consistency of response to explosive volcanism for Ireland’s climatically sensitive Northeast Atlantic location and the large proportional contribution of volcanism to historic cold event frequencies here. Our results expose, moreover, the extent to which volcanism has impacted winter-season climate for the region, and can help to further resolve the complex spatial patterns of Northern Hemisphere winter-season cooling versus warming after major eruptions. (letter)

  9. Numerical Modeling of the Severe Cold Weather Event over Central Europe (January 2006

    Directory of Open Access Journals (Sweden)

    D. Hari Prasad

    2010-01-01

    Full Text Available Cold waves commonly occur in higher latitudes under prevailing high pressure systems especially during winter season which cause serious economical loss and cold related death. Accurate prediction of such severe weather events is important for decision making by administrators and for mitigation planning. An Advanced high resolution Weather Research and Forecasting mesoscale model is used to simulate a severe cold wave event occurred during January 2006 over Europe. The model is integrated for 31 days starting from 00UTC of 1 January 2006 with 30 km horizontal resolution. Comparison of the model derived area averaged daily mean temperatures at 2m height from different zones over the central Europe with observations indicates that the model is able to simulate the occurrence of the cold wave with the observed time lag of 1 to 3days but with lesser intensity. The temperature, winds, surface pressure and the geopential heights at 500 hPa reveal that the cold wave development associates with the southward progression of a high pressure system and cold air advection. The results have good agreement with the analysis fields indicates that the model has the ability to reproduce the time evolution of the cold wave event.

  10. Coupled prediction of flood response and debris flow initiation during warm and cold season events in the Southern Appalachians, USA

    Science.gov (United States)

    Tao, J.; Barros, A. P.

    2013-07-01

    Debris flows associated with rainstorms are a frequent and devastating hazard in the Southern Appalachians in the United States. Whereas warm season events are clearly associated with heavy rainfall intensity, the same cannot be said for the cold season events. Instead, there is a relationship between large (cumulative) rainfall events independently of season, and thus hydrometeorological regime, and debris flows. This suggests that the dynamics of subsurface hydrologic processes play an important role as a trigger mechanism, specifically through soil moisture redistribution by interflow. The first objective of this study is to investigate this hypothesis. The second objective is to assess the physical basis for a regional coupled flood prediction and debris flow warning system. For this purpose, uncalibrated model simulations of well-documented debris flows in headwater catchments of the Southern Appalachians using a 3-D surface-groundwater hydrologic model coupled with slope stability models are examined in detail. Specifically, we focus on two vulnerable headwater catchments that experience frequent debris flows, the Big Creek and the Jonathan Creek in the Upper Pigeon River Basin, North Carolina, and three distinct weather systems: an extremely heavy summertime convective storm in 2011; a persistent winter storm lasting several days; and a severe winter storm in 2009. These events were selected due to the optimal availability of rainfall observations, availability of detailed field surveys of the landslides shortly after they occurred, which can be used to evaluate model predictions, and because they are representative of events that cause major economic losses in the region. The model results substantiate that interflow is a useful prognostic of conditions necessary for the initiation of slope instability, and should therefore be considered explicitly in landslide hazard assessments. Moreover, the relationships between slope stability and interflow are

  11. Coupled prediction of flood response and debris flow initiation during warm- and cold-season events in the Southern Appalachians, USA

    Science.gov (United States)

    Tao, J.; Barros, A. P.

    2014-01-01

    Debris flows associated with rainstorms are a frequent and devastating hazard in the Southern Appalachians in the United States. Whereas warm-season events are clearly associated with heavy rainfall intensity, the same cannot be said for the cold-season events. Instead, there is a relationship between large (cumulative) rainfall events independently of season, and thus hydrometeorological regime, and debris flows. This suggests that the dynamics of subsurface hydrologic processes play an important role as a trigger mechanism, specifically through soil moisture redistribution by interflow. We further hypothesize that the transient mass fluxes associated with the temporal-spatial dynamics of interflow govern the timing of shallow landslide initiation, and subsequent debris flow mobilization. The first objective of this study is to investigate this relationship. The second objective is to assess the physical basis for a regional coupled flood prediction and debris flow warning system. For this purpose, uncalibrated model simulations of well-documented debris flows in headwater catchments of the Southern Appalachians using a 3-D surface-groundwater hydrologic model coupled with slope stability models are examined in detail. Specifically, we focus on two vulnerable headwater catchments that experience frequent debris flows, the Big Creek and the Jonathan Creek in the Upper Pigeon River Basin, North Carolina, and three distinct weather systems: an extremely heavy summertime convective storm in 2011; a persistent winter storm lasting several days; and a severe winter storm in 2009. These events were selected due to the optimal availability of rainfall observations; availability of detailed field surveys of the landslides shortly after they occurred, which can be used to evaluate model predictions; and because they are representative of events that cause major economic losses in the region. The model results substantiate that interflow is a useful prognostic of conditions

  12. Effects of age and season on haematological parameters of donkeys during the rainy and cold-dry seasons

    Science.gov (United States)

    Zakari, Friday Ocheja; Ayo, Joseph Olusegun; Rekwot, Peter Ibrahim; Kawu, Mohammed Umar

    2015-12-01

    The aim of the study was to investigate the effects of age and season on haematological parameters of donkeys at rest during the rainy and cold-dry seasons. Thirty healthy donkeys divided into three groups based on their age served as the subjects. During each season, blood sample was collected from each donkey thrice, 2 weeks apart, for haematological analysis, and the dry-bulb temperature (DBT), relative humidity (RH) and temperature-humidity index (THI) were obtained thrice each day during the experimental period using standard procedures. During the rainy season, the mean DBT (33.05 ± 0.49 °C), RH (73.63 ± 1.09 %) and THI (84.39 ± 0.71) were higher ( P donkeys were higher ( P donkeys were higher ( P < 0.05) in the rainy than in the cold-dry season. In conclusion, PCV, RBC, Hb and LYM were considerably higher in foals than yearlings or adults during the rainy season, while erythrocytic indices and platelet counts were higher in adults or yearlings than in foals in both seasons. Erythrocytic indices, PLT and N/L were higher in the rainy than the cold-dry season in adults, yearlings and foals.

  13. Decreasing but still significant facilitation effect of cold-season macrophytes on wetlands purification function during cold winter.

    Science.gov (United States)

    Zou, Xiangxu; Zhang, Hui; Zuo, Jie; Wang, Penghe; Zhao, Dehua; An, Shuqing

    2016-06-01

    To identify the facilitation effect of a cool-season aquatic macrophyte (FEam) for use in effluent purification via constructed floating wetlands (CFWs) and to determine the possible pathways used during a winter period with an average temperature of less than 5 °C, pilot-scale CFWs were planted with the cold-season macrophyte Oenanthe clecumbens and were operated as batch systems. Although some leaves withered, the roots retained relatively high levels of activity during the winter, which had average air and water temperatures of 3.63 and 5.04 °C, respectively. The N and P removal efficiencies in CFWs decreased significantly in winter relative to those in late autumn. The presence of cool-season plants resulted in significant improvements in N and P removal, with a FEam of 15.23-25.86% in winter. Microbial N removal accounted for 71.57% of the total N removed in winter, and the decrease in plant uptake was the dominant factor in the wintertime decrease in N removal relative to that in late autumn. These results demonstrate the importance of cold-season plants in CFWs for the treatment of secondary effluent during cold winters.

  14. Significance of cold-season respiration and photosynthesis in a subarctic heath ecosystem in Northern Sweden

    DEFF Research Database (Denmark)

    Larsen, Klaus Steenberg; Ibrom, Andreas; Jonasson, S.

    2007-01-01

    While substantial cold-season respiration has been documented in most arctic and alpine ecosystems in recent years, the significance of cold-season photosynthesis in these biomes is still believed to be small. In a mesic, subartic heath during both the cold and warm season, we measured in situ...... ecosystem respiration and photosynthesis with a chamber technique at ambient conditions and at artificially, increased frequency of freeze-thaw (FT) cycles during fall and spring. We fitted the measured ecosystem exchange rates to respiration and photosynthesis models with R-2-values ranging from 0.81 to 0.......85. As expected, estimated cold-season (October, November, April and May) respiration was significant and accounted for at least 22% of the annual respiratory CO2 flux. More surprisingly, estimated photosynthesis during this period accounted for up to 19% of the annual gross CO2 uptake, suggesting that cold...

  15. Multiproxy evidence for terrestrial and aquatic ecosystem responses during the 8.2 ka cold event as recorded at Højby Sø, Denmark

    DEFF Research Database (Denmark)

    Hede, Mikkel Ulfeldt; Rasmussen, Peter; Noe-Nygaard, Nanna

    2010-01-01

    ecosystems to the 8.2 ka cold event. A reduced pollen production by thermophilous deciduous tree taxa in the period c. 8250–8000 cal yr BP reveal that the forest ecosystem was affected by low temperatures during the summer and winter/early-spring seasons. This finding is consistent with the timing of the 8.......2 ka cold event as registered in the Greenland ice cores. At Højby Sø, the climate anomaly appears to have started 200–250 yr earlier than the 8.2 ka cold event as the lake proxy data provide strong evidence for a precipitation-induced distinct increase in catchment soil erosion beginning around 8500...... cal yr BP. Alteration of the terrestrial environment then resulted in a major aquatic ecosystem change with nutrient enrichment of the lake and enhanced productivity, which lasted until c. 7900 cal yr BP. Keywords: 8.2 ka cold event; Lake sediments; Palaeoclimate; Pollen; Macrofossils; Geochemistry...

  16. European cold season lightning map for wind turbines based on radio soundings

    DEFF Research Database (Denmark)

    Vogel, Stephan; Holbøll, Joachim; Lopez, Javier

    2016-01-01

    conditions for self-triggered upward lightning, as being observed in Japan and Spain, are identified. This map may give an indication if a potential wind power plant or structure has the risk to be affected by frequent lightning attachments in the cold season which are predominantly upward initiated......In this paper, the meteorological data of cold season thunderstorms in Japan and Spain are reviewed to determine the threshold conditions at which cold season lightning was recorded in the past. The variables investigated are the height of the -10°C and 0°C isotherms above ground, the wind velocity......, the precipitable water in the cloud, and the wind direction. Meteorological data of 72 radio sounding stations in Europe is analyzed for a 5 year period (2009-2014) in the months from October until March. Based on this information, a European map has been created indicating areas where the meteorological...

  17. Variability in cold front activities modulating cool-season evaporation from a southern inland water in the USA

    International Nuclear Information System (INIS)

    Liu Heping; Blanken, Peter D; Weidinger, Tamas; Nordbo, Annika; Vesala, Timo

    2011-01-01

    Understanding seasonal variations in the evaporation of inland waters (e.g., lakes and reservoirs) is important for water resource management as well as the prediction of the hydrological cycles in response to climate change. We analyzed eddy covariance-based evaporation measurements from the Ross Barnett Reservoir (32 deg. 26'N, 90 0 02'W; which is always ice-free) in central Mississippi during the cool months (i.e., September-March) of 2007 and 2008, and found that the variability in cold front activities (i.e., passages of cold fronts and cold/dry air masses behind cold fronts) played an important role in modulating the exchange of sensible (H) and latent (λE) heat fluxes. Our analysis showed that 2007's warmer cool season had smaller mean H and λE than 2008's cooler cool season. This implies that the warmer cool season did not accelerate evaporation and heat exchange between the water surface and the atmosphere. Instead, more frequent cold fronts and longer periods of cold/dry air masses behind the cold fronts in 2008 resulted in overall larger H and λE as compared with 2007, this primarily taking the form of sporadic short-term rapid 'pulses' of H and λE losses from the water's surface. These results suggest that future climate-induced changes in frequency of cold fronts and the meteorological properties of the air masses behind cold fronts (e.g., wind speeds, temperature, and humidity), rather than other factors of climate change, would produce significant variations in the water surface's energy fluxes and subsequent evaporation rates.

  18. Modeling a cold-air drainage event with a wireless sensor network

    OpenAIRE

    Brian R. Zutta; Eric A. Graham; Philip W. Rundel

    2005-01-01

    A wireless network of sensors was used to characterize a cold-air drainage event in the canyon surrounding the James Reserve. The flow of cold air at night and the first hours of sunrise have major ecological consequences by limiting the vegetation types to those tolerant of freeze and thaw cycles. A network of wireless sensors provides the opportunity to track this event in real time and fully characterize the cold air flow down the canyon, which may last 1.5 hours, and the pooling of cold a...

  19. Optimal design and application of a compound cold storage system combining seasonal ice storage and chilled water storage

    NARCIS (Netherlands)

    Yan, C.; Shi, W.; Li, X.; Zhao, Y.

    2016-01-01

    Seasonal cold storage using natural cold sources for cooling is a sustainable cooling technique. However, this technique suffers from limitations such as large storage space and poor reliability. Combining seasonal storage with short-term storage might be a promising solution while it is not

  20. Antibiotic Use in Cold and Flu Season and Prescribing Quality: A Retrospective Cohort Study.

    Science.gov (United States)

    Alsan, Marcella; Morden, Nancy E; Gottlieb, Joshua D; Zhou, Weiping; Skinner, Jonathan

    2015-12-01

    Excessive antibiotic use in cold and flu season is costly and contributes to antibiotic resistance. The study objective was to develop an index of excessive antibiotic use in cold and flu season and determine its correlation with other indicators of prescribing quality. We included Medicare beneficiaries in the 40% random sample denominator file continuously enrolled in fee-for-service benefits for 2010 or 2011 (7,961,201 person-years) and extracted data on prescription fills for oral antibiotics that treat respiratory pathogens. We collapsed the data to the state level so they could be merged with monthly flu activity data from the Centers for Disease Control and Prevention. Linear regression, adjusted for state-specific mean antibiotic use and demographic characteristics, was used to estimate how antibiotic prescribing responded to state-specific flu activity. Flu-activity associated antibiotic use varied substantially across states-lowest in Vermont and Connecticut, highest in Mississippi and Florida. There was a robust positive correlation between flu-activity associated prescribing and use of medications that often cause adverse events in the elderly (0.755; Pantibiotic use was positively correlated with prescribing high-risk medications to the elderly and negatively correlated with beta-blocker use after myocardial infarction. These findings suggest that excessive antibiotic use reflects low-quality prescribing. They imply that practice and policy solutions should go beyond narrow, antibiotic specific, approaches to encourage evidence-based prescribing for the elderly Medicare population.

  1. Warm-season severe wind events in Germany

    Science.gov (United States)

    Gatzen, Christoph

    2013-04-01

    A 15-year data set of wind measurements was analyzed with regard to warm season severe wind gusts in Germany. For April to September of the years 1997 to 2011, 1035 wind measurements of 26 m/s or greater were found. These wind reports were associated with 268 wind events. In total, 252 convective wind events contributed to 837 (81%) of the wind reports, 16 non-convective synoptic-scale wind events contributed to 198 reports (19%). Severe wind events were found with synoptic situations characterized by rather strong mid-level flow and advancing mid-level troughs. Severe convective wind events were analyzed using radar images and classified with respect to the observed radar structure. The most important convective mode was squall lines that were associated with one third of all severe wind gusts, followed by groups, bow echo complexes, and bow echoes. Supercells and cells were not associated with many wind reports. The low contribution of isolated cells indicates that rather large-scale forcing by synoptic-scale features like fronts is important for German severe wind events. Bow echoes were found to be present for 58% of all wind reports. The movement speed of bow echoes indicated a large variation with a maximum speed of 33 m/s. Extreme wind events as well as events with more than 15 wind reports were found to be related to higher movement speeds. Concentrating on the most intense events, derechos seem to be very important to the warm season wind threat in Germany. Convective events with a path length of more than 400 km contributed to 36% of all warm-season wind gusts in this data set. Furthermore, eight of nine extreme gusts exceeding 40 m/s were recorded with derecho events.

  2. Relative contributions of synoptic and intraseasonal variations to strong cold events over eastern China

    Science.gov (United States)

    Song, Lei; Wu, Renguang; Jiao, Yang

    2018-06-01

    The present study investigates the relative roles of intraseasonal oscillations (ISOs) and synoptic variations in strong cold events over eastern China during the boreal winter. The ISOs and synoptic variations explain about 55% and 20% of the total area-mean temperature anomaly in eastern China, respectively. The advection of synoptic winds on synoptic temperature gradients has a leading contribution to the temperature decrease before the cold events and thus the synoptic variations are important in determining the time of peak cold anomalies. The ISOs have a larger role in sustaining the cold events. The height anomalies associated with ISOs and synoptic variations are manifested as Rossby wave trains propagating along the polar front jet over the Eurasian continent before the cold events. They both contribute to the deepening of the East Asian trough and the development of cold events. Compared to the ISO wave train, the synoptic wave train has a smaller spatial scale and moves faster. There are obvious intraseasonal signals in the stratosphere about 1 week before the cold events over eastern China. Large negative height anomalies associated with the weakening of the polar vortex are observed over the North Atlantic. These anomalies move eastwards and propagate downwards after reaching the west coast of Europe. The downward moving stratospheric signal triggers height anomalies in the troposphere over the entrance region of the polar front jet. Then the anomalies propagate towards East Asia along the wave train, contributing to the intensification of the Siberian high and the East Asian trough and the occurrence of cold events over eastern China.

  3. Preliminary results on seasonal changes in flower bud cold hardiness of sour cherry

    DEFF Research Database (Denmark)

    Liu, Guangping; Pagter, Majken; Andersen, Lillie

    2012-01-01

    . cerasus ‘Kelleriis 16’ under natural conditions, and investigated seasonal changes in flower bud cold hardiness of ‘Stevnsbaer Birgitte’. In a cold winter with unusual low temperatures in December, the injury rate of buds of ‘Stevnsbaer Birgitte’ was significantly higher than that of ‘Kelleriis 16......’, confirming that buds of the latter cultivar are considerably more cold hardy than buds of ‘Stevnsbaer Birgitte’. The majority of frost injuries in buds of ‘Stevnsbaer Birgitte’ occurred mid-winter, but dehardening appeared fast, indicating that the critical injury times of buds of ‘Stevnsbaer Birgitte...

  4. Adaptation to seasonality and the winter freeze

    Directory of Open Access Journals (Sweden)

    Jill Christine Preston

    2013-06-01

    Full Text Available Flowering plants initially diversified during the Mesozoic era at least 140 million years ago in regions of the world where temperate seasonal environments were not encountered. Since then several cooling events resulted in the contraction of warm and wet environments and the establishment of novel temperate zones in both hemispheres. In response, less than half of modern angiosperm families have members that evolved specific adaptations to cold seasonal climates, including cold acclimation, freezing tolerance, endodormancy, and vernalization responsiveness. Despite compelling evidence for multiple independent origins, the level of genetic constraint on the evolution of adaptations to seasonal cold is not well understood. However, the recent increase in molecular genetic studies examining the response of model and crop species to seasonal cold offers new insight into the evolutionary lability of these traits. This insight has major implications for our understanding of complex trait evolution, and the potential role of local adaptation in response to past and future climate change. In this review, we discuss the biochemical, morphological, and developmental basis of adaptations to seasonal cold, and synthesize recent literature on the genetic basis of these traits in a phylogenomic context. We find evidence for multiple genetic links between distinct physiological responses to cold, possibly reinforcing the coordinated expression of these traits. Furthermore, repeated recruitment of the same or similar ancestral pathways suggests that land plants might be somewhat pre-adapted to dealing with temperature stress, perhaps making inducible cold traits relatively easy to evolve.

  5. Diurnal and seasonal variations of greenhouse gas emissions from a naturally ventilated dairy barn in a cold region

    Science.gov (United States)

    Huang, Dandan; Guo, Huiqing

    2018-01-01

    Carbon dioxide (CO2), methane (CH4), and nitrous oxide (N2O) emissions were quantified for a naturally ventilated free-stall dairy barn in the Canadian Prairies climate through continuous measurements for a year from February 2015 to January 2016, with ventilation rate estimated by a CO2 mass balance method. The results were categorized into seasonal emission profiles with monthly data measured on a typical day, and diurnal profiles in cold (January), warm (July), and mild seasons (October) of all three gases. Seasonal CO2, CH4, and N2O concentrations greatly fluctuated within ranges of 593-2433 ppm, 15-152 ppm, and 0.32-0.40 ppm, respectively, with obviously higher concentrations in the cold season. Emission factors of the three gases were summarized: seasonal N2O emission varied between 0.5 and 10 μg s-1 AU-1 with lower emission in the cold season, while seasonal CO2 and CH4 emissions were within narrow ranges of 112-119 mg s-1 AU-1 and 2.5-3.5 mg s-1 AU-1. The result suggested a lower enteric CH4 emission for dairy cows than that estimated by Environment Canada (2014). Significant diurnal effects (P 0.05), but obvious diurnal variations in all seasons. In comparison with previous studies, it was found that the dairy barn in a cold region climate with smaller vent openings had relatively higher indoor CO2 and CH4 concentrations, but comparable CO2 and CH4 emissions to most previous studies. Besides, ventilation rate, temperature, and relative humidity all significantly affected the three gas concentrations with the outdoor temperature being the most relevant factor (P < 0.01); however, they showed less or no statistical relations to emissions.

  6. Evaluation of Durum Wheat Lines for Tolerance to Early Season Cold via Early Planting

    Directory of Open Access Journals (Sweden)

    V. Rashidi

    2010-10-01

    Full Text Available Cold stress is one of the environmental factors that affect planting date of durum wheat in mountainous North West areas of Iran. To study tolerance of 36 Durum wheat lines for cold, an experiment was conducted in mid winter (mid of February at the Agricultural Research Station of Islamic Azad University, Tabriz Branch, in 2007. Experimental design used was simple lattice. The results of analysis of variance showed that the lines under study responded differently to cold as to traits like percentage of survival, yield and its components. This indicates existence of genetic diversity among durum wheat lines. Percentage of survival of the lines 30, 5, 16, 27, 31 and 35 were for higher than those at other lines. Thus, they can be considered to be tolerant to early season cold. Comparison of means showed that lines 35, 31, 16 and 5 possessed higher percentage of survival and other percent survival also correlated positive with plant height, number of fertile spike seed yield and 1000 grain weight. As a whole line 35 was found to be more tolerant to early season cold than the others were. Cluster analysis was divided 36 lines into three groups. Lines in the third group possessed higher percentage of survival, plant height, number of fertile spike, biomass and high yield than their over all means.

  7. Effect of season on peripheral resistance to localised cold stress

    Science.gov (United States)

    Tanaka, M.; Harimura, Y.; Tochihara, Y.; Yamazaki, S.; Ohnaka, T.; Matsui, J.; Yoshida, K.

    1984-03-01

    This study was carried out to determine the effect that seasonal changes have on the effect of localised cold stress on peripheral temperatures using the foot immersion method with a cold water bath. The subjects were six males and four females. The data were obtained in April, July, October and January. Skin temperature of the right index finger, the forehead, the arm, the cheek, the second toe and the instep were measured before, during and after the immersion of the feet in water at 15°C for 10 mins, as well as oxygen consumption before immersion of the feet. The average finger temperature was highest during foot immersion in the summer, next highest in the winter, then spring, and the lowest during foot immersion in the autumn. The finger temperatures during the pre-immersion period in the autumn tended to be lower than in other seasons. The finger temperatures during the pre-immersion period affected the temperature change of the finger during the immersion period. The rate of increase of the toe temperature and the foot temperature during post-immersion in the summer and the spring were greater than those in the autumn and winter. Oxygen consumption during the pre-immersion period in the autumn was significantly lower than in the other seasons (pCooling the feet caused no significant changes in the temperatures the cheek, forehead or forearm. The cheek temperature in the summer and autumn was cooler than corresponding temperatures taken in the winter and spring.

  8. Elevated Temperature and CO2 Stimulate Late-Season Photosynthesis But Impair Cold Hardening in Pine[OPEN

    Science.gov (United States)

    2016-01-01

    Rising global temperature and CO2 levels may sustain late-season net photosynthesis of evergreen conifers but could also impair the development of cold hardiness. Our study investigated how elevated temperature, and the combination of elevated temperature with elevated CO2, affected photosynthetic rates, leaf carbohydrates, freezing tolerance, and proteins involved in photosynthesis and cold hardening in Eastern white pine (Pinus strobus). We designed an experiment where control seedlings were acclimated to long photoperiod (day/night 14/10 h), warm temperature (22°C/15°C), and either ambient (400 μL L−1) or elevated (800 μmol mol−1) CO2, and then shifted seedlings to growth conditions with short photoperiod (8/16 h) and low temperature/ambient CO2 (LTAC), elevated temperature/ambient CO2 (ETAC), or elevated temperature/elevated CO2 (ETEC). Exposure to LTAC induced down-regulation of photosynthesis, development of sustained nonphotochemical quenching, accumulation of soluble carbohydrates, expression of a 16-kD dehydrin absent under long photoperiod, and increased freezing tolerance. In ETAC seedlings, photosynthesis was not down-regulated, while accumulation of soluble carbohydrates, dehydrin expression, and freezing tolerance were impaired. ETEC seedlings revealed increased photosynthesis and improved water use efficiency but impaired dehydrin expression and freezing tolerance similar to ETAC seedlings. Sixteen-kilodalton dehydrin expression strongly correlated with increases in freezing tolerance, suggesting its involvement in the development of cold hardiness in P. strobus. Our findings suggest that exposure to elevated temperature and CO2 during autumn can delay down-regulation of photosynthesis and stimulate late-season net photosynthesis in P. strobus seedlings. However, this comes at the cost of impaired freezing tolerance. Elevated temperature and CO2 also impaired freezing tolerance. However, unless the frequency and timing of extreme low

  9. A concentrated outbreak of tornadoes, downbursts and microbursts, and implications regarding vortex classification

    Science.gov (United States)

    Forbes, G. S.; Wakimoto, R. M.

    1983-01-01

    A remarkable case of severe weather occurred near Springfield, Illinois on 6 August 1977. Aerial and ground surveys revealed that 17 cyclonic vortices, an anticyclonic vortex, 10 downbursts and 19 microbursts occurred in a limited (20 km x 40 km) area, associated with a bow-shaped radar echo. About half of the vortices appeared to have occurred along a gust front. Some of the others appear to have occurred within the circulation of a mesocyclone accompanying the bow echo, but these vortices seem to have developed specifically in response to localized boundary-layer vorticity generation associated with horizontal and vertical wind shears on the periphery of microbursts. Some of these vortices, and other destructive vortices in the literature, do not qualify as tornadoes as defined in the Glossary of Meteorology. A more pragmatic definition of a tornado is suggested.

  10. Long-Term Climate Trends and Extreme Events in Northern Fennoscandia (1914–2013

    Directory of Open Access Journals (Sweden)

    Sonja Kivinen

    2017-02-01

    Full Text Available We studied climate trends and the occurrence of rare and extreme temperature and precipitation events in northern Fennoscandia in 1914–2013. Weather data were derived from nine observation stations located in Finland, Norway, Sweden and Russia. The results showed that spring and autumn temperatures and to a lesser extent summer temperatures increased significantly in the study region, the observed changes being the greatest for daily minimum temperatures. The number of frost days declined both in spring and autumn. Rarely cold winter, spring, summer and autumn seasons had a low occurrence and rarely warm spring and autumn seasons a high occurrence during the last 20-year interval (1994–2013, compared to the other 20-year intervals. That period was also characterized by a low number of days with extremely low temperature in all seasons (4–9% of all extremely cold days and a high number of April and October days with extremely high temperature (36–42% of all extremely warm days. A tendency of exceptionally high daily precipitation sums to grow even higher towards the end of the study period was also observed. To summarize, the results indicate a shortening of the cold season in northern Fennoscandia. Furthermore, the results suggest significant declines in extremely cold climate events in all seasons and increases in extremely warm climate events particularly in spring and autumn seasons.

  11. Elevated Temperature and CO2 Stimulate Late-Season Photosynthesis But Impair Cold Hardening in Pine.

    Science.gov (United States)

    Chang, Christine Y; Fréchette, Emmanuelle; Unda, Faride; Mansfield, Shawn D; Ensminger, Ingo

    2016-10-01

    Rising global temperature and CO 2 levels may sustain late-season net photosynthesis of evergreen conifers but could also impair the development of cold hardiness. Our study investigated how elevated temperature, and the combination of elevated temperature with elevated CO 2 , affected photosynthetic rates, leaf carbohydrates, freezing tolerance, and proteins involved in photosynthesis and cold hardening in Eastern white pine (Pinus strobus). We designed an experiment where control seedlings were acclimated to long photoperiod (day/night 14/10 h), warm temperature (22°C/15°C), and either ambient (400 μL L -1 ) or elevated (800 μmol mol -1 ) CO 2 , and then shifted seedlings to growth conditions with short photoperiod (8/16 h) and low temperature/ambient CO 2 (LTAC), elevated temperature/ambient CO 2 (ETAC), or elevated temperature/elevated CO 2 (ETEC). Exposure to LTAC induced down-regulation of photosynthesis, development of sustained nonphotochemical quenching, accumulation of soluble carbohydrates, expression of a 16-kD dehydrin absent under long photoperiod, and increased freezing tolerance. In ETAC seedlings, photosynthesis was not down-regulated, while accumulation of soluble carbohydrates, dehydrin expression, and freezing tolerance were impaired. ETEC seedlings revealed increased photosynthesis and improved water use efficiency but impaired dehydrin expression and freezing tolerance similar to ETAC seedlings. Sixteen-kilodalton dehydrin expression strongly correlated with increases in freezing tolerance, suggesting its involvement in the development of cold hardiness in P. strobus Our findings suggest that exposure to elevated temperature and CO 2 during autumn can delay down-regulation of photosynthesis and stimulate late-season net photosynthesis in P. strobus seedlings. However, this comes at the cost of impaired freezing tolerance. Elevated temperature and CO 2 also impaired freezing tolerance. However, unless the frequency and timing of extreme low

  12. Cold-season patterns of reserve and soluble carbohydrates in sugar maple and ice-damaged trees of two age classes following drought

    Science.gov (United States)

    B. L. Wong; K. L. Baggett; A. H. Rye

    2009-01-01

    This study examines the effects of summer drought on the composition and profiles of cold-season reserve and soluble carbohydrates in sugar maple (Acer saccharum Marsh.) trees (50-100 years old or ~200 years old) in which the crowns were nondamaged or damaged by the 1998 ice storm. The overall cold season reserve...

  13. Modeled seasonality of glacial abrupt climate events

    Energy Technology Data Exchange (ETDEWEB)

    Flueckiger, Jacqueline [Institute of Arctic and Alpine Research, University of Colorado, Boulder, CO (United States); Environmental Physics, Institute of Biogeochemistry and Pollutant Dynamics, ETH Zuerich, Zurich (Switzerland); Knutti, Reto [Institute for Atmospheric and Climate Science, ETH Zuerich, Zurich (Switzerland); White, James W.C. [Institute of Arctic and Alpine Research, University of Colorado, Boulder, CO (United States); Renssen, Hans [Vrije Universiteit Amsterdam, Faculty of Earth and Life Sciences, Amsterdam (Netherlands)

    2008-11-15

    Greenland ice cores, as well as many other paleo-archives from the northern hemisphere, recorded a series of 25 warm interstadial events, the so-called Dansgaard-Oeschger (D-O) events, during the last glacial period. We use the three-dimensional coupled global ocean-atmosphere-sea ice model ECBILT-CLIO and force it with freshwater input into the North Atlantic to simulate abrupt glacial climate events, which we use as analogues for D-O events. We focus our analysis on the Northern Hemisphere. The simulated events show large differences in the regional and seasonal distribution of the temperature and precipitation changes. While the temperature changes in high northern latitudes and in the North Atlantic region are dominated by winter changes, the largest temperature increases in most other land regions are seen in spring. Smallest changes over land are found during the summer months. Our model simulations also demonstrate that the temperature and precipitation change patterns for different intensifications of the Atlantic meridional overturning circulation are not linear. The extent of the transitions varies, and local non-linearities influence the amplitude of the annual mean response as well as the response in different seasons. Implications for the interpretation of paleo-records are discussed. (orig.)

  14. Potential applications of heat and cold stress indices to sporting events.

    Science.gov (United States)

    Moran, D S

    2001-01-01

    Many recreational and elite athletes participate in sporting events every year. However, when these events are conducted under hostile environmental conditions, whether in cold or hot climates, the risk for environmental illnesses increases. The higher the stress, the greater is the potential for performance decrements, injuries and illnesses. The most common expected heat illnesses are heat exhaustion and heatstroke, whereas hypothermia and frostbite are the most common cold injuries. However, heat and cold stress indices can minimise the risk for environmental illnesses and dehydration by following the recommendations and guidelines which accompany these indices. Stress indices should be used by athletes, coaches and officials to prevent injury and improve safety conditions for competitors and participants in recreational activities. All participants should be made aware of warning signs, susceptibility and predisposing conditions. Coaches should be aware of their responsibility with regard to the safety of their trainees, and officials should organise and plan events at times that are likely to be of low environmental stress. However, they must also be prepared and equipped with the means necessary to reduce injuries and treat cases of collapse and environmental illnesses. The lack of a friendly, small and simple device for environmental stress assessment is probably the main reason why stress indices are not commonly used. We believe that developing a new portable heat and cold stress monitor in wristwatch format for use by those exposed to environmental stress could help in the decision making process of expected hazards caused by exercising and working in hostile environments, and might help prevent heat and cold illnesses.

  15. Impacts of an Extreme Early-Season Freeze Event in the Interior Pacific Northwest (30 October-3 November 2002) on Western Juniper Woodlands.

    Science.gov (United States)

    Knapp, Paul A.; Soulé, Peter T.

    2005-07-01

    In mid-autumn 2002, an exceptional 5-day cold spell affected much of the interior Pacific Northwest, with minimum temperatures averaging 13°C below long-term means (1953-2002). On 31 October, minimum temperature records occurred at 98 of the 106 recording stations, with records lowered in some locations by 9°C. Calculation of recurrence intervals of minimum temperatures shows that 50% of the stations experienced a >500-yr event. The synoptic conditions responsible were the development of a pronounced high pressure ridge over western Canada and an intense low pressure area centered in the Intermountain West that promoted strong northeasterly winds. The cold spell occurred near the end of the growing season for an ecologically critical and dominant tree species of the interior Pacific Northwest—western juniper—and followed an extended period of severe drought. In spring 2003, it became apparent that the cold had caused high rates of tree mortality and canopy dieback in a species that is remarkable for its longevity and resistance to climatic stress. The cold event altered western juniper dominance in some areas, and this alteration may have long-term impacts on water budgets, fire intensities and frequencies, animal species interrelationships, and interspecific competition among plant species.

  16. Variability of cold season surface air temperature over northeastern China and its linkage with large-scale atmospheric circulations

    Science.gov (United States)

    Zhuang, Yuanhuang; Zhang, Jingyong; Wang, Lin

    2018-05-01

    Cold temperature anomalies and extremes have profound effects on the society, the economy, and the environment of northeastern China (NEC). In this study, we define the cold season as the months from October to April, and investigate the variability of cold season surface air temperature (CSAT) over NEC and its relationships with large-scale atmospheric circulation patterns for the period 1981-2014. The empirical orthogonal function (EOF) analysis shows that the first EOF mode of the CSAT over NEC is characterized by a homogeneous structure that describes 92.2% of the total variance. The regionally averaged CSAT over NEC is closely linked with the Arctic Oscillation ( r = 0.62, 99% confidence level) and also has a statistically significant relation with the Polar/Eurasian pattern in the cold season. The positive phases of the Arctic Oscillation and the Polar/Eurasian pattern tend to result in a positive geopotential height anomaly over NEC and a weakened East Asian winter monsoon, which subsequently increase the CSAT over NEC by enhancing the downward solar radiation, strengthening the subsidence warming and warm air advection. Conversely, the negative phases of these two climate indices result in opposite regional atmospheric circulation anomalies and decrease the CSAT over NEC.

  17. Probabilistic Nowcasting of Low-Visibility Procedure States at Vienna International Airport During Cold Season

    Science.gov (United States)

    Kneringer, Philipp; Dietz, Sebastian J.; Mayr, Georg J.; Zeileis, Achim

    2018-04-01

    Airport operations are sensitive to visibility conditions. Low-visibility events may lead to capacity reduction, delays and economic losses. Different levels of low-visibility procedures (lvp) are enacted to ensure aviation safety. A nowcast of the probabilities for each of the lvp categories helps decision makers to optimally schedule their operations. An ordered logistic regression (OLR) model is used to forecast these probabilities directly. It is applied to cold season forecasts at Vienna International Airport for lead times of 30-min out to 2 h. Model inputs are standard meteorological measurements. The skill of the forecasts is accessed by the ranked probability score. OLR outperforms persistence, which is a strong contender at the shortest lead times. The ranked probability score of the OLR is even better than the one of nowcasts from human forecasters. The OLR-based nowcasting system is computationally fast and can be updated instantaneously when new data become available.

  18. Observations and simulations of the seasonal evolution of snowpack cold content and its relation to snowmelt and the snowpack energy budget

    Science.gov (United States)

    Jennings, Keith S.; Kittel, Timothy G. F.; Molotch, Noah P.

    2018-05-01

    Cold content is a measure of a snowpack's energy deficit and is a linear function of snowpack mass and temperature. Positive energy fluxes into a snowpack must first satisfy the remaining energy deficit before snowmelt runoff begins, making cold content a key component of the snowpack energy budget. Nevertheless, uncertainty surrounds cold content development and its relationship to snowmelt, likely because of a lack of direct observations. This work clarifies the controls exerted by air temperature, precipitation, and negative energy fluxes on cold content development and quantifies the relationship between cold content and snowmelt timing and rate at daily to seasonal timescales. The analysis presented herein leverages a unique long-term snow pit record along with validated output from the SNOWPACK model forced with 23 water years (1991-2013) of quality controlled, infilled hourly meteorological data from an alpine and subalpine site in the Colorado Rocky Mountains. The results indicated that precipitation exerted the primary control on cold content development at our two sites with snowfall responsible for 84.4 and 73.0 % of simulated daily gains in the alpine and subalpine, respectively. A negative surface energy balance - primarily driven by sublimation and longwave radiation emission from the snowpack - during days without snowfall provided a secondary pathway for cold content development, and was responsible for the remaining 15.6 and 27.0 % of cold content additions. Non-zero cold content values were associated with reduced snowmelt rates and delayed snowmelt onset at daily to sub-seasonal timescales, while peak cold content magnitude had no significant relationship to seasonal snowmelt timing. These results suggest that the information provided by cold content observations and/or simulations is most relevant to snowmelt processes at shorter timescales, and may help water resource managers to better predict melt onset and rate.

  19. Transport pathways for Asian pollution outflow over the Pacific: Interannual and seasonal variations

    Science.gov (United States)

    Liu, Hongyu; Jacob, Daniel J.; Bey, Isabelle; Yantosca, Robert M.; Duncan, Bryan N.; Sachse, Glen W.

    2003-10-01

    The meteorological pathways contributing to Asian pollution outflow over the Pacific are examined with a global three-dimensional model analysis of CO observations from the Transport and Chemical Evolution over the Pacific (TRACE-P) aircraft mission (February-April 2001). The model is used also to place the TRACE-P observations in an interannual (1994-2001) and seasonal context. The major process driving Asian pollution outflow in spring is frontal lifting ahead of southeastward-moving cold fronts (the leading edge of cold surges) and transport in the boundary layer behind the cold fronts. Orographic lifting over central and eastern China combines with the cold fronts to promote the transport of Chinese pollution to the free troposphere. Outflow of seasonal biomass burning in Southeast Asia during spring takes place mostly by deep convection but also by northeastward transport and frontal lifting, mixing with the anthropogenic outflow. Boundary layer outflow over the western Pacific is largely devoid of biomass burning influence. European and African (biomass burning) plumes in Asian outflow during TRACE-P were weak (pollution signal. Spring 2001 (La Niña) was characterized by unusually frequent cold surge events in the Asian Pacific rim and strong convection in Southeast Asia, leading to unusually strong boundary layer outflow of anthropogenic emissions and convective outflow of biomass burning emissions in the upper troposphere. The Asian outflow flux of CO to the Pacific is found to vary seasonally by a factor of 3-4 (maximum in March and minimum in summer). The March maximum results from frequent cold surge events and seasonal biomass burning emissions.

  20. Characterization of water quality and suspended sediment during cold-season flows, warm-season flows, and stormflows in the Fountain and Monument Creek watersheds, Colorado, 2007–2015

    Science.gov (United States)

    Miller, Lisa D.; Stogner, Sr., Robert W.

    2017-09-01

    From 2007 through 2015, the U.S. Geological Survey, in cooperation with Colorado Springs City Engineering, conducted a study in the Fountain and Monument Creek watersheds, Colorado, to characterize surface-water quality and suspended-sediment conditions for three different streamflow regimes with an emphasis on characterizing water quality during storm runoff. Data collected during this study were used to evaluate the effects of stormflows and wastewater-treatment effluent discharge on Fountain and Monument Creeks in the Colorado Springs, Colorado, area. Water-quality samples were collected at 2 sites on Upper Fountain Creek, 2 sites on Monument Creek, 3 sites on Lower Fountain Creek, and 13 tributary sites during 3 flow regimes: cold-season flow (November–April), warm-season flow (May–October), and stormflow from 2007 through 2015. During 2015, additional samples were collected and analyzed for Escherichia coli (E. coli) during dry weather conditions at 41 sites, located in E. coli impaired stream reaches, to help identify source areas and scope of the impairment.Concentrations of E. coli, total arsenic, and dissolved copper, selenium, and zinc in surface-water samples were compared to Colorado in-stream standards. Stormflow concentrations of E. coli frequently exceeded the recreational use standard of 126 colonies per 100 milliliters at main-stem and tributary sites by more than an order of magnitude. Even though median E. coli concentrations in warm-season flow samples were lower than median concentrations in storm-flow samples, the water quality standard for E. coli was still exceeded at most main-stem sites and many tributary sites during warm-season flows. Six samples (three warm-season flow and three stormflow samples) collected from Upper Fountain Creek, upstream from the confluence of Monument Creek, and two stormflow samples collected from Lower Fountain Creek, downstream from the confluence with Monument Creek, exceeded the acute water

  1. The Formation of Charon's Red Poles from Seasonally Cold-Trapped Volatiles

    Science.gov (United States)

    Grundy, W. M.; Cruikshank, D. P.; Gladstone, D. R.; Howett, C. J. A.; Lauer, T. R.; Spencer, J. R.; Summers, M. E.; Buie, M. W.; Earle, A. M.; Ennico, K.; hide

    2016-01-01

    A unique feature of Plutos large satellite Charon is its dark red northern polar cap. Similar colours on Plutos surface have been attributed to tholin-like organic macromolecules produced by energetic radiation processing of hydrocarbons. The polar location on Charon implicates the temperature extremes that result from Charons high obliquity and long seasons in the production of this material. The escape of Pluto's atmosphere provides a potential feedstock for a complex chemistry. Gas from Pluto that is transiently cold-trapped and processed at Charon's winter pole was proposed as an explanation for the dark coloration on the basis of an image of Charon's northern hemisphere, but not modelled quantitatively. Here we report images of the southern hemisphere illuminated by Pluto-shine and also images taken during the approach phase that show the northern polar cap over a range of longitudes. We model the surface thermal environment on Charon and the supply and temporary cold-trapping of material escaping from Pluto, as well as the photolytic processing of this material into more complex and less volatile molecules while cold-trapped. The model results are consistent with the proposed mechanism for producing the observed colour pattern on Charon.

  2. Severe Weather Events over Southeastern Brazil during the 2016 Dry Season

    Directory of Open Access Journals (Sweden)

    Amanda Rehbein

    2018-01-01

    Full Text Available Southeastern Brazil is the most populated and economically developed region of this country. Its climate consists of two distinct seasons: the dry season, extending from April to September, the precipitation is significantly reduced in comparison to that of the wet season, which extends from October to March. However, during nine days of the 2016 dry season, successive convective systems were associated with atypical precipitation events, tornadoes and at least one microburst over the southern part of this region. These events led to flooding, damages to buildings, shortages of electricity and water in several places, many injuries, and two documented deaths. The present study investigates the synoptic and dynamical features related to these anomalous events. The convective systems were embedded in an unstable environment with intense low-level jet flow and strong wind shear and were supported by a sequence of extratropical cyclones occurring over the Southwest Atlantic Ocean. These features were intensified by the Madden–Julian oscillation (MJO in its phase 8 and by intense negative values of the Pacific South America (PSA 2 mode.

  3. Cold-season solar input and ambivalent thermal behavior brought by climber greenwalls

    International Nuclear Information System (INIS)

    Jim, C.Y.

    2015-01-01

    Most greenwall studies focus on cooling and energy conservation in the warm season, and tropical cold-season has received little attention. This field-experimental study in humid-subtropical Hong Kong evaluated winter thermal behavior of climber greenwalls. Orientation and weather factors regulated solar-irradiation regimes with critical impact on vegetation thermal responses. Temperature differentiation occurred mainly on sunny day, with subdued variations on cloudy and rainy days. The south greenwall on sunny day received the highest solar-energy input, bringing divergent surface temperature in three climber species. The daytime descending cooling sequence was: Control-air > Pyrostegia venusta > Bauhinia corymbosa > Ficus pumila > Control-surface. Heat-sink effect related to foliage-thickness and moisture-content influenced climber thermal responses. Exceeding a solar-irradiance threshold of 500 Wm"−"2 was a prerequisite for notable solar-warming and transpiration-cooling, bringing well-differentiated climber-surface temperature. Cooling of vegetation-surface and Anterior-ambient-air was contrasted by warming behind the greenwall. Posterior-airgap with trapped stagnant air and Posterior-concrete-surface were warmed consistently above control concrete-surface on sunny and cloudy days. This winter passive warming mechanism denotes a new dimension in thermal benefits operating behind the greenwall. The thermal-gradient can transmit heat into indoor space, with benefits on human comfort, health and energy conservation. - Highlights: • Cold-season thermal regimes and benefits of climber greenwalls in tropics was studied. • Greenwall plots were installed as a field-experiment to evaluated six related factors. • Descending cooling sequence: Pyrostegia venusta > Bauhinia corymbosa > Ficus pumila. • Solar radiation intensity and foliage heat-sink effect determined climber cooling. • Posterior airgap and Posterior concrete-surface were warmed to provide indoor

  4. Influenza epidemics, seasonality, and the effects of cold weather on cardiac mortality

    Science.gov (United States)

    2012-01-01

    Background More people die in the winter from cardiac disease, and there are competing hypotheses to explain this. The authors conducted a study in 48 US cities to determine how much of the seasonal pattern in cardiac deaths could be explained by influenza epidemics, whether that allowed a more parsimonious control for season than traditional spline models, and whether such control changed the short term association with temperature. Methods The authors obtained counts of daily cardiac deaths and of emergency hospital admissions of the elderly for influenza during 1992–2000. Quasi-Poisson regression models were conducted estimating the association between daily cardiac mortality, and temperature. Results Controlling for influenza admissions provided a more parsimonious model with better Generalized Cross-Validation, lower residual serial correlation, and better captured Winter peaks. The temperature-response function was not greatly affected by adjusting for influenza. The pooled estimated increase in risk for a temperature decrease from 0 to −5°C was 1.6% (95% confidence interval (CI) 1.1-2.1%). Influenza accounted for 2.3% of cardiac deaths over this period. Conclusions The results suggest that including epidemic data explained most of the irregular seasonal pattern (about 18% of the total seasonal variation), allowing more parsimonious models than when adjusting for seasonality only with smooth functions of time. The effect of cold temperature is not confounded by epidemics. PMID:23025494

  5. Cold fronts in the Colombian Caribbean Sea and their relationship to extreme wave events

    Science.gov (United States)

    Ortiz-Royero, J. C.; Otero, L. J.; Restrepo, J. C.; Ruiz, J.; Cadena, M.

    2013-11-01

    Extreme ocean waves in the Caribbean Sea are commonly related to the effects of storms and hurricanes during the months of June through November. The collapse of 200 m of the Puerto Colombia pier in March 2009 revealed the effects of meteorological phenomena other than storms and hurricanes that may be influencing the extreme wave regime in the Colombian Caribbean. The marked seasonality of these atmospheric fronts was established by analyzing the meteorological-marine reports of the Instituto de Hidrología, Meteorología y Estudios Ambientales of Colombia (IDEAM, based on its initials in Spanish) and the Centro de Investigación en Oceanografía y Meteorología of Colombia (CIOH, based on its initials in Spanish) during the last 16 yr. The highest number of cold fronts was observed during the months of January, February, and March, with 6 fronts occurring per year. An annual trend was observed and the highest number of fronts occurred in 2010 (20 in total); moreover, an annual strong relationship between the maximum average wave values and the cold fronts in the central zone of the Colombian Caribbean during the first three months of the year was established. In addition, the maximum values of the significant height produced by the passage of cold fronts during the last 16 yr were identified. Although the Colombian Caribbean has been affected by storms and hurricanes in the past, this research allows us to conclude that there is a strong relationship between cold fronts and the largest waves in the Colombian Caribbean during the last 16 yr, which have caused damage to coastal infrastructure. We verified that the passage of a cold front corresponded to the most significant extreme wave event of the last two decades in the Colombian Caribbean, which caused the structural collapse of the Puerto Colombia pier, located near the city of Barranquilla, between 5 and 10 March 2009. This information is invaluable when evaluating average and extreme wave regimes for the

  6. Role of cold surge and MJO on rainfall enhancement over indonesia during east asian winter monsoon

    Science.gov (United States)

    Fauzi, R. R.; Hidayat, R.

    2018-05-01

    Intensity of precipitation in Indonesia is influenced by convection and propagation of southwest wind. Objective of this study is to analyze the relationship between cold surge and the phenomenon of intra-seasonal climate variability Madden-julian Oscillation (MJO) for affecting precipitation in Indonesia. The data used for identifying the occurrence of cold surge are meridional wind speed data from the ERA-Interim. In addition, this study also used RMM1 and RMM2 index data from Bureau of Meteorology (BOM) for identifying MJO events. The results showed that during East Asian Winter Monsoon (EAWM) in 15 years (2000-2015), there are 362 cold surge events, 186 MJO events, and 113 cold surge events were associated with MJO events. The spread of cold surge can penetrate to equator and brought mass of water vapor that causes dominant precipitation in the Indonesian Sea up to 50-75% from climatological precipitation during EAWM. The MJO convection activity that moves from west to east also increases precipitation, but the distribution of rainfall is wider than cold surge, especially in Eastern Indonesia. MJO and cold surge simultaneously can increase rainfall over 100-150% in any Indonesian region that affected by MJO and cold surge events. The mechanism of heavy rainfall is illustrated by high activity of moisture transport in areas such as Java Sea and coastal areas of Indonesia.

  7. Effects of cold fronts on ozone in the Houston-Galveston-Brazoria Area

    Science.gov (United States)

    Lei, R.; Talbot, R. W.; Wang, Y.; Wang, S. C.; Estes, M. J.

    2017-12-01

    A cold front may have confounding effects on ozone by bringing in contaminated air masses to an area and causing lower temperatures which likely lead to low ozone production rates. Literature reports on individual cold front events showing increasing and decreasing effects on ozone. The Houston-Galveston-Brazoria (HGB) area as the energy capital of USA suffers relatively high ozone levels. The effect of cold fronts on HGB ozone in the long-term range remains unknown. Weather Prediction Center (WPC) Surface Analysis Archive from National Oceanic and Atmospheric Administration (NOAA) which records cold fronts' positions since 2003 has been employed in this study. The results show the count of cold fronts passing the HGB area shows no clear trend but great interannual variation. Cold front appearance in summer is much less than in other seasons. In general, both mean MDA8 and background ozone during cold front days increased compared non-cold front days. This increasing effect has been enhanced during post-front days and summer season. Cluster analysis on meteorological parameters shows cold front days with high precipitation or wind speed could lower the MDA8 and background ozone but the proportion of those days are low in all cold front days. It may explain why cold fronts show increasing effects on ozone in the HGB area.

  8. Preservation of potassium balance is strongly associated with insect cold tolerance in the field: a seasonal study of Drosophila subobscura.

    Science.gov (United States)

    MacMillan, Heath A; Schou, Mads F; Kristensen, Torsten N; Overgaard, Johannes

    2016-05-01

    There is interest in pinpointing genes and physiological mechanisms explaining intra- and interspecific variations in cold tolerance, because thermal tolerance phenotypes strongly impact the distribution and abundance of wild animals. Laboratory studies have highlighted that the capacity to preserve water and ion homeostasis is linked to low temperature survival in insects. It remains unknown, however, whether adaptive seasonal acclimatization in free-ranging insects is governed by the same physiological mechanisms. Here, we test whether cold tolerance in field-caught Drosophila subobscura is high in early spring and lower during summer and whether this transition is associated with seasonal changes in the capacity of flies to preserve water and ion balance during cold stress. Indeed, flies caught during summer were less cold tolerant, and exposure of these flies to sub-zero temperatures caused a loss of haemolymph water and increased the concentration of K(+) in the haemolymph (as in laboratory-reared insects). This pattern of ion and water balance disruption was not observed in more cold-tolerant flies caught in early spring. Thus, we here provide a field verification of hypotheses based on laboratory studies and conclude that the ability to maintain ion homeostasis is important for the ability of free-ranging insects to cope with chilling. © 2016 The Author(s).

  9. Calcium addition at the Hubbard Brook Experimental Forest increases the capacity for stress tolerance and carbon capture in red spruce (Picea rubens) trees during the cold season

    Science.gov (United States)

    Paul G. Schaberg; Rakesh Minocha; Stephanie Long; Joshua M. Halman; Gary J. Hawley; Christopher. Eagar

    2011-01-01

    Red spruce (Picea rubens Sarg.) trees are uniquely vulnerable to foliar freezing injury during the cold season (fall and winter), but are also capable of photosynthetic activity if temperatures moderate. To evaluate the influence of calcium (Ca) addition on the physiology of red spruce during the cold season, we measured concentrations of foliar...

  10. The forcing of monthly precipitation variability over Southwest Asia during the Boreal cold season

    Science.gov (United States)

    Hoell, Andrew; Shukla, Shraddhanand; Barlow, Mathew; Cannon, Forest; Kelley, Colin; Funk, Christopher C.

    2015-01-01

    Southwest Asia, deemed as the region containing the countries of Afghanistan, Iran, Iraq and Pakistan, is water scarce and receives nearly 75% of its annual rainfall during8 the boreal cold season of November-April. The forcing of Southwest Asia precipitation has been previously examined for the entire boreal cold season from the perspective of climate variability originating over the Atlantic and tropical Indo-Pacific Oceans. Here, we examine the inter-monthly differences in precipitation variability over Southwest Asia and the atmospheric conditions directly responsible in forcing monthly November-April precipitation. Seasonally averaged November-April precipitation over Southwest Asia is significantly correlated with sea surface temperature (SST) patterns consistent with Pacific Decadal Variability (PDV), the El Nino-Southern Oscillation (ENSO) and the warming trend of SST (Trend). On the contrary, the precipitation variability during individual months of November-April are unrelated and are correlated with SST signatures that include PDV, ENSO and Trend in different combinations. Despite strong inter-monthly differences in precipitation variability during November- April over Southwest Asia, similar atmospheric circulations, highlighted by a stationary equivalent barotropic Rossby wave centered over Iraq, force the monthly spatial distributions of precipitation. Tropospheric waves on the eastern side of the equivalent barotropic Rossby wave modifies the flux of moisture and advects the mean temperature gradient, resulting in temperature advection that is balanced by vertical motions over Southwest Asia. The forcing of monthly Southwest Asia precipitation by equivalent barotropic Rossby waves is different than the forcing by baroclinic Rossby waves associated with tropically-forced-only modes of climate variability.

  11. Winter Season Mortality: Will Climate Warming Bring Benefits?

    Science.gov (United States)

    Kinney, Patrick L; Schwartz, Joel; Pascal, Mathilde; Petkova, Elisaveta; Tertre, Alain Le; Medina, Sylvia; Vautard, Robert

    2015-06-01

    Extreme heat events are associated with spikes in mortality, yet death rates are on average highest during the coldest months of the year. Under the assumption that most winter excess mortality is due to cold temperature, many previous studies have concluded that winter mortality will substantially decline in a warming climate. We analyzed whether and to what extent cold temperatures are associated with excess winter mortality across multiple cities and over multiple years within individual cities, using daily temperature and mortality data from 36 US cities (1985-2006) and 3 French cities (1971-2007). Comparing across cities, we found that excess winter mortality did not depend on seasonal temperature range, and was no lower in warmer vs. colder cities, suggesting that temperature is not a key driver of winter excess mortality. Using regression models within monthly strata, we found that variability in daily mortality within cities was not strongly influenced by winter temperature. Finally we found that inadequate control for seasonality in analyses of the effects of cold temperatures led to spuriously large assumed cold effects, and erroneous attribution of winter mortality to cold temperatures. Our findings suggest that reductions in cold-related mortality under warming climate may be much smaller than some have assumed. This should be of interest to researchers and policy makers concerned with projecting future health effects of climate change and developing relevant adaptation strategies.

  12. Observation of seasonal variation of atmospheric multiple-muon events in the MINOS near and far detectors

    Energy Technology Data Exchange (ETDEWEB)

    Adamson, P. [Fermi National Accelerator Lab. (FNAL), Batavia, IL (United States). et al.

    2015-06-09

    We report the first observation of seasonal modulations in the rates of cosmic ray multiple-muon events at two underground sites, the MINOS Near Detector with an overburden of 225 mwe, and the MINOS Far Detector site at 2100 mwe. Thus, at the deeper site, multiple-muon events with muons separated by more than 8 m exhibit a seasonal rate that peaks during the summer, similar to that of single-muon events. In contrast and unexpectedly, the rate of multiple-muon events with muons separated by less than 5–8 m, and the rate of multiple-muon events in the smaller, shallower Near Detector, exhibit a seasonal rate modulation that peaks in the winter.

  13. The upcoming mutual event season for the Patroclus-Menoetius Trojan binary

    Science.gov (United States)

    Grundy, W. M.; Noll, K. S.; Buie, M. W.; Levison, H. F.

    2018-05-01

    We present new Hubble Space Telescope and ground-based Keck observations and new Keplerian orbit solutions for the mutual orbit of binary Jupiter Trojan asteroid (617) Patroclus and Menoetius, targets of NASA's Lucy mission. We predict event times for the upcoming mutual event season, which is anticipated to run from late 2017 through mid 2019.

  14. A Projection of the Effects of the Climate Change Induced by Increased CO2 on Extreme Hydrologic Events in the Western U.S

    International Nuclear Information System (INIS)

    Kim, Jinwon

    2005-01-01

    The effects of increased atmospheric CO2 on the frequency of extreme hydrologic events in the Western United States (WUS) for the 10-yr period of 2040-2049 are examined using dynamically downscaled regional climate change signals. For assessing the changes in the occurrence of hydrologic extremes, downscaled climate change signals in daily precipitation and runoff that are likely to indicate the occurrence of extreme events are examined. Downscaled climate change signals in the selected indicators suggest that the global warming induced by increased CO2 is likely to increase extreme hydrologic events in the WUS. The indicators for heavy precipitation events show largest increases in the mountainous regions of the northern California Coastal Range and the Sierra Nevada. Increased cold season precipitation and increased rainfall-portion of precipitation at the expense of snowfall in the projected warmer climate result in large increases in high runoff events in the Sierra Nevada river basins that are already prone to cold season flooding in todays climate. The projected changes in the hydrologic characteristics in the WUS are mainly associated with higher freezing levels in the warmer climate and increases in the cold season water vapor influx from the Pacific Ocean

  15. Weakened cyclones, intensified anticyclones and recent extreme cold winter weather events in Eurasia

    International Nuclear Information System (INIS)

    Zhang Xiangdong; Lu Chuhan; Guan Zhaoyong

    2012-01-01

    Extreme cold winter weather events over Eurasia have occurred more frequently in recent years in spite of a warming global climate. To gain further insight into this regional mismatch with the global mean warming trend, we analyzed winter cyclone and anticyclone activities, and their interplay with the regional atmospheric circulation pattern characterized by the semi-permanent Siberian high. We found a persistent weakening of both cyclones and anticyclones between the 1990s and early 2000s, and a pronounced intensification of anticyclone activity afterwards. It is suggested that this intensified anticyclone activity drives the substantially strengthening and northwestward shifting/expanding Siberian high, and explains the decreased midlatitude Eurasian surface air temperature and the increased frequency of cold weather events. The weakened tropospheric midlatitude westerlies in the context of the intensified anticyclones would reduce the eastward propagation speed of Rossby waves, favoring persistence and further intensification of surface anticyclone systems. (letter)

  16. Cold-season atmospheric response to the natural variability of the Atlantic meridional overturning circulation

    Energy Technology Data Exchange (ETDEWEB)

    Gastineau, Guillaume; Frankignoul, Claude [LOCEAN/IPSL, Universite Pierre et Marie Curie, 4 place Jussieu, BP100, Paris Cedex 05 (France)

    2012-07-15

    The influence of the natural variability of the Atlantic meridional overturning circulation (AMOC) on the atmosphere is studied in multi-centennial simulations of six global climate models, using Maximum Covariance Analysis (MCA). In all models, a significant but weak influence of the AMOC changes is found during the Northern Hemisphere cold-season, when the ocean leads the atmosphere by a few years. Although the oceanic pattern slightly varies, an intensification of the AMOC is followed in all models by a weak sea level pressure response that resembles a negative phase of the North Atlantic Oscillation (NAO). The signal amplitude is typically 0.5 hPa and explains about 10% of the yearly variability of the NAO in all models. The atmospheric response seems to be due primarily due to an increase of the heat loss along the North Atlantic Current and the subpolar gyre, associated with an AMOC-driven warming. Sea-ice changes appear to be less important. The stronger heating is associated to a southward shift of the lower-tropospheric baroclinicity and a decrease of the eddy activity in the North Atlantic storm track, which is consistent with the equivalent barotropic perturbation resembling the negative phase of the NAO. This study thus provides some evidence of an atmospheric signature of the AMOC in the cold-season, which may have some implications for the decadal predictability of climate in the North Atlantic region. (orig.)

  17. Aspects of cold intrusions over Greece during autumn

    Science.gov (United States)

    Mita, Constantina; Marinaki, Aggeliki; Zeini, Konstantina; Konstantara, Metaxia

    2010-05-01

    the 25 years, the slight trends identified, decreasing in the number of cold intrusions and increasing in the maximum temperature decrease at the level of 850 hPa were statistically insignificant. Finally, special attention is given to an exceptional event of cold intrusion which followed an extreme high temperature period for the season, in the beginning of October 1991. For this particular case, the underlying physical generation mechanism is studied thoroughly by analysing synoptic maps from ECMWF (0000 UTC and 1200 UTC) at the levels of 500 hPa, 850 hPa and MSL for the period 1/10/1991-6/10/1991. Additionally, the evolution of the cold intrusion as it passes over the country is examined in detail in conjunction with the observed physical phenomena such as gale force winds, moderate snowfall, heavy rainfall and thunderstorms.

  18. Estimation of the time of death of decomposed or skeletonized bodies found outdoors in cold season in Sapporo city, located in the northern district of Japan.

    Science.gov (United States)

    Matoba, Kotaro; Terazawa, Koichi

    2008-03-01

    In Sapporo city, located in the northern district of Japan, it is very difficult to estimate the time of death of decomposed or skeletonized bodies found outdoors in cold season (November-April) because postmortem changes are markedly retarded in the season compared with warm season (May-October), and the bodies are often damaged and skeletonized by carnivorous animals such as wild dogs and foxes. However, they cannot damage the brain in the cranium. The brain is mainly damaged by fly larvae. In Sapporo city, we can estimate that the time of death of a cadaver found outdoors in the cold season is in the beginning of November or before if fly larvae hatched in autumn exist on the cadaver, and that the time of death is in the beginning of November or after if fly larvae hatched in autumn do not exist and most of the brain remains in the cranium.

  19. Characterization and effects of cold fronts in the Colombian Caribbean Coast and their relationship to extreme wave events

    Science.gov (United States)

    Ortiz-Royero, J. C.; Otero, L. J.; Restrepo, J. C.; Ruiz, J.; Cadena, M.

    2013-07-01

    Extreme ocean waves in the Caribbean Sea are commonly related to the effects of storms and hurricanes during the months of June through November. The collapse of 200 m of the Puerto Colombia pier in March 2009 revealed the effects of meteorological phenomena other than storms and hurricanes that may be influencing the extreme wave regime in the Colombian Caribbean. The marked seasonality of these atmospheric fronts was established by analyzing the meteorological-marine reports of Instituto de Hidrología, Meteorología y Estudios Ambientales of Colombia (IDEAM, based on its initials in Spanish) and Centro de Investigación en Oceanografía y Meteorología of Colombia (CIOH, based on its initials in Spanish). The highest occurrences were observed during the months of January, February, and March, with 6 fronts occurring per year. An annual trend was not observed, although the highest number of fronts occurred in 2010 (20 in total). An annual strong relationship between the maximum average wave values and the cold fronts, in the central zone of the Colombian Caribbean during the first three months of the year was established. In addition, the maximum values of the significant height produced by the passage of cold fronts during the last 16 yr were identified. Although the Colombian Caribbean has been affected by storms and hurricanes in the past, this research allows us to conclude that, there is a strong relationship between cold fronts and the largest waves in the Colombian Caribbean during the last 16 yr, which have caused damage to coastal infrastructure. We verified that the passage of a cold front corresponded to the most significant extreme wave event of the last two decades in the Colombian Caribbean, which caused the structural collapse of the Puerto Colombia pier, located near the city of Barranquilla, between 5 and 10 March 2009. This information is invaluable when evaluating average and extreme wave regimes for the purpose of informing the design of

  20. Ecology and social system of northern gibbons living in cold seasonal forests.

    Science.gov (United States)

    Guan, Zhen-Hua; Ma, Chang-Yong; Fei, Han-Lan; Huang, Bei; Ning, Wen-He; Ni, Qing-Yong; Jiang, Xue-Long; Fan, Peng-Fei

    2018-07-18

    Gibbons in China represent the northernmost margin of present day gibbon species distribution (around N25°). Compared to tropical habitats, northern gibbon habitats are characterized by low temperatures and remarkable seasonal variation in fruit abundance. How gibbons adapt to their cold and seasonal habitats and what ecological factors affect their sociality are key questions for understanding their ecology and social system evolution, the elucidation of which will contribute to the conservation of these special populations/species. According to preliminary short-term studies, northern gibbons consume more leaves and use larger home ranges than tropical gibbons. Interestingly, some Nomascus groups consist of more than one adult female. However, these preliminary results are not well understood or incorporated into current socio-ecological theories regarding gibbon species. To better understand northern gibbons, our team has systematically studied three habituated groups of Nomascus concolor, three groups of N. nasutus, and two habituated groups of Hoolock tianxing since 2002. In this paper, we stress the challenges facing gibbons living in northern habitats and summarize their behavioral adaptations to their harsh environments. We also describe the northern gibbon social system and discuss the potential relationships between their ecology and sociality. Finally, we highlight future research questions related to northern gibbons in China.

  1. Ecology and social system of northern gibbons living in cold seasonal forests

    Directory of Open Access Journals (Sweden)

    Zhen-Hua Guan

    2018-07-01

    Full Text Available Gibbons in China represent the northernmost margin of present day gibbon species distribution (around N25°. Compared to tropical habitats, northern gibbon habitats are characterized by low temperatures and remarkable seasonal variation in fruit abundance. How gibbons adapt to their cold and seasonal habitats and what ecological factors affect their sociality are key questions for understanding their ecology and social system evolution, the elucidation of which will contribute to the conservation of these special populations/species. According to preliminary short-term studies, northern gibbons consume more leaves and use larger home ranges than tropical gibbons. Interestingly, some Nomascus groups consist of more than one adult female. However, these preliminary results are not well understood or incorporated into current socio-ecological theories regarding gibbon species. To better understand northern gibbons, our team has systematically studied three habituated groups of Nomascus concolor, three groups of N. nasutus, and two habituated groups of Hoolock tianxing since 2002. In this paper, we stress the challenges facing gibbons living in northern habitats and summarize their behavioral adaptations to their harsh environments. We also describe the northern gibbon social system and discuss the potential relationships between their ecology and sociality. Finally, we highlight future research questions related to northern gibbons in China.

  2. Sorghum Landrace Collections from Cooler Regions of the World Exhibit Magnificent Genetic Differentiation and Early Season Cold Tolerance

    Directory of Open Access Journals (Sweden)

    Frank Maulana

    2017-05-01

    Full Text Available Cold temperature is an important abiotic stress affecting sorghum production in temperate regions. It reduces seed germination, seedling emergence and seedling vigor thus limiting the production of the crop both temporally and spatially. The objectives of this study were (1 to assess early season cold temperature stress response of sorghum germplasm from cooler environments and identify sources of tolerance for use in breeding programs, (2 to determine population structure and marker-trait association among these germplasms for eventual development of marker tools for improving cold tolerance. A total of 136 sorghum accessions from cooler regions of the world were phenotyped for seedling growth characteristics under cold temperature imposed through early planting. The accessions were genotyped using 67 simple sequence repeats markers spanning all ten linkage groups of sorghum, of which 50 highly polymorphic markers were used in the analysis. Genetic diversity and population structure analyses sorted the population into four subpopulations. Several accessions distributed in all subpopulations showed either better or comparable level of tolerance to the standard cold tolerance source, Shan qui red. Association analysis between the markers and seedling traits identified markers Xtxp34, Xtxp88, and Xtxp319 as associated with seedling emergence, Xtxp211 and Xtxp304 with seedling dry weight, and Xtxp20 with seedling height. The markers were detected on chromosomes previously found to harbor QTLs associated with cold tolerance in sorghum. Once validated these may serve as genomic tools in marker-assisted breeding or for screening larger pool of genotypes to identify additional sources of cold tolerance.

  3. Cold injuries.

    Science.gov (United States)

    Kruse, R J

    1995-01-01

    There are two categories of cold injury. The first is hypothermia, which is a systemic injury to cold, and the second is frostbite, which is a local injury. Throughout history, entire armies, from George Washington to the Germans on the Russian Front in World War II, have fallen prey to prolonged cold exposure. Cold injury is common and can occur in all seasons if ambient temperature is lower than the core body temperature. In the 1985 Boston Marathon, even though it was 76 degrees and sunny, there were 75 runners treated for hypothermia. In general, humans adapt poorly to cold exposure. Children are at particular risk because of their relatively greater surface area/body mass ratio, causing them to cool even more rapidly than adults. Because of this, the human's best defense against cold injury is to limit his/her exposure to cold and to dress appropriately. If cold injury has occurred and is mild, often simple passive rewarming such as dry blankets and a warm room are sufficient treatment.

  4. Developing a Framework for Seamless Prediction of Sub-Seasonal to Seasonal Extreme Precipitation Events in the United States.

    Science.gov (United States)

    Rosendahl, D. H.; Ćwik, P.; Martin, E. R.; Basara, J. B.; Brooks, H. E.; Furtado, J. C.; Homeyer, C. R.; Lazrus, H.; Mcpherson, R. A.; Mullens, E.; Richman, M. B.; Robinson-Cook, A.

    2017-12-01

    Extreme precipitation events cause significant damage to homes, businesses, infrastructure, and agriculture, as well as many injures and fatalities as a result of fast-moving water or waterborne diseases. In the USA, these natural hazard events claimed the lives of more than 300 people during 2015 - 2016 alone, with total damage reaching $24.4 billion. Prior studies of extreme precipitation events have focused on the sub-daily to sub-weekly timeframes. However, many decisions for planning, preparing and resilience-building require sub-seasonal to seasonal timeframes (S2S; 14 to 90 days), but adequate forecasting tools for prediction do not exist. Therefore, the goal of this newly funded project is an enhancement in understanding of the large-scale forcing and dynamics of S2S extreme precipitation events in the United States, and improved capability for modeling and predicting such events. Here, we describe the project goals, objectives, and research activities that will take place over the next 5 years. In this project, a unique team of scientists and stakeholders will identify and understand weather and climate processes connected with the prediction of S2S extreme precipitation events by answering these research questions: 1) What are the synoptic patterns associated with, and characteristic of, S2S extreme precipitation evens in the contiguous U.S.? 2) What role, if any, do large-scale modes of climate variability play in modulating these events? 3) How predictable are S2S extreme precipitation events across temporal scales? 4) How do we create an informative prediction of S2S extreme precipitation events for policymaking and planing? This project will use observational data, high-resolution radar composites, dynamical climate models and workshops that engage stakeholders (water resource managers, emergency managers and tribal environmental professionals) in co-production of knowledge. The overarching result of this project will be predictive models to reduce of

  5. The Next-Generation Goddard Convective-Stratiform Heating Algorithm: Addressing Higher Latitude, Cold Season, and Synoptic Systems

    Science.gov (United States)

    Wu, D.; Tao, W. K.; Lang, S. E.

    2016-12-01

    The Goddard Convective-Stratiform Heating (or CSH) algorithm is used to retrieve estimates of cloud heating over the global Tropics using TRMM rainfall data and a set of look-up-tables (LUTs) derived from a series of multi-week cloud-resolving model (CRM) simulations using the Goddard Cumulus Ensemble model (or GCE). These simulations link satellite observables (i.e., surface rainfall and stratiform fraction) with cloud heating profiles, which are not directly observable. The current CSH LUTs are differentiated with respect to surface rainfall characteristics, which is effective for tropical and continental summertime environments. However, with the launch of GPM in 2014, the range over which such algorithms can be applied has been extended from the Tropics and mid-latitudes to higher latitudes, including cold season and synoptic weather systems. Accordingly, the CSH algorithm and LUTs need to be updated for higher latitude events. In this study, NU-WRF was employed at 1 km to simulate winter systems in the US. A, new methodology has been adopted to construct LUTs utilizing satellite-observable 3D intensity fields, such as radar reflectivity. The new methodology/LUTs can be then applied to simulated radar fields to derive cloud heating for comparison against the model simulated heating. The model heating is treated as the `truth' as it is self-consistent with the simulated radar fields. This `consistency check' approach is a common well-established first step in algorithm development (e.g., the earlier CSH). The LUTs will be improved by iterating the consistency checks to quantitatively evaluate the similarities between the retrieved and simulated heating. The evaluations will be performed for different weather events, including northeast winter storms and atmospheric rivers.

  6. Cold-season temperature in the Swiss Alps from AD 1100-1500; trends, intra-annual variability and forcing factors

    Science.gov (United States)

    de Jong, Rixt; Kamenik, Christian; Grosjean, Martin

    2010-05-01

    To fully understand past climatic changes and their forcing factors, detailed reconstructions of past summer and winter temperatures are required. Winter temperature reconstructions are scarce, however, because most biological proxies are biased towards the growing season. This study presents a detailed reconstruction of winter temperatures based on Chrysophyte stomatocysts, silicious scales formed by so-called 'golden algae'. Previous studies (Kamenik and Schmidt, 2005; Pla and Catalan, 2005) have demonstrated the sensitivity of these algae to cold-season temperatures. Chrysophyte stomatocyst analysis was carried out on varved sediments from Lake Silvaplana (1791 m a.s.l.) at annual to near-annual resolution for two periods; AD 1100-1500 and AD 1870-2004. For both periods the reference date 'date of spring mixing' (Smix) was reconstructed using a transfer function developed for the Austrian Alps (Kamenik and Schmidt, 2005). In the Austrian Alps, Smix was primarily driven by air temperature in the cold season. The strength of stomatocysts as a proxy for winter temperature was tested by directly comparing reconstructed Smix with measured temperatures from nearby meteostation Sils Maria for the period AD 1870 - 2004. Correlation was highest (R = -0.6; p number of eruptions during the much shorter instrumental period (Fischer et al., 2007). References: T. Crowley. Science 289, 270-277 (2000) E. Fischer et al. Geophys. Res. Lett. 34, L05707 (2007) C. Kamenik and R. Schmidt. Boreas 34, 477-489 (2005) I. Larocque-Tobler et al. Quat. Sci. Rev., accepted. S. Pla and J. Catalan. Clim. Dyn. 24, 263-278 (2005) M. Trachsel et al. Manuscript in review

  7. Spatial patterns of throughfall isotopic composition at the event and seasonal timescales

    Science.gov (United States)

    Allen, Scott T.; Keim, Richard F.; McDonnell, Jeffrey J.

    2015-03-01

    Spatial variability of throughfall isotopic composition in forests is indicative of complex processes occurring in the canopy and remains insufficiently understood to properly characterize precipitation inputs to the catchment water balance. Here we investigate variability of throughfall isotopic composition with the objectives: (1) to quantify the spatial variability in event-scale samples, (2) to determine if there are persistent controls over the variability and how these affect variability of seasonally accumulated throughfall, and (3) to analyze the distribution of measured throughfall isotopic composition associated with varying sampling regimes. We measured throughfall over two, three-month periods in western Oregon, USA under a Douglas-fir canopy. The mean spatial range of δ18O for each event was 1.6‰ and 1.2‰ through Fall 2009 (11 events) and Spring 2010 (7 events), respectively. However, the spatial pattern of isotopic composition was not temporally stable causing season-total throughfall to be less variable than event throughfall (1.0‰; range of cumulative δ18O for Fall 2009). Isotopic composition was not spatially autocorrelated and not explained by location relative to tree stems. Sampling error analysis for both field measurements and Monte-Carlo simulated datasets representing different sampling schemes revealed the standard deviation of differences from the true mean as high as 0.45‰ (δ18O) and 1.29‰ (d-excess). The magnitude of this isotopic variation suggests that small sample sizes are a source of substantial experimental error.

  8. Protozoans bacterivory in a subtropical environment during a dry/cold and a rainy/warm season

    Directory of Open Access Journals (Sweden)

    Karina F. Hisatugo

    2014-01-01

    Full Text Available In aquatic ecosystems, bacteria are controlled by several organisms in the food chain, such as protozoa, that use them as food source. This study aimed to quantify the ingestion and clearance rates of bacteria by ciliates and heterotrophic nanoflagellates (HNF in a subtropical freshwater reservoir (Monjolinho reservoir -São Carlos -Brazil during one year period, in order to verify their importance as consumers and controllers of bacteria in two seasons, a dry/cold and a rainy/warm one. For this purpose, in situ bacterivory experiments were carried out bimonthly using fluorescently labeled bacteria with 5-(4,6 diclorotriazin-2yl aminofluorescein (DTAF. Although ciliates have shown the highest individual ingestion and clearance rates, bacterivory was dominated by HNF, who showed higher population ingestion rates (mean of 9,140 bacteria h-1mL-1 when compared to ciliates (mean of 492 bacteria h-1mL-1. The greater predation impact on bacterial communities was caused mainly by the small HNF (< 5 µm population, especially in the rainy season, probably due to the abundances of these organisms, the precipitation, trophic index state and water temperature that were higher in this period. Thus, the protozoan densities together with environmental variables were extremely relevant in determining the seasonal pattern of bacterivory in Monjolinho reservoir.

  9. Seasonal monitoring of deep-sea megabenthos in Barkley Canyon cold seep by internet operated vehicle (IOV.

    Directory of Open Access Journals (Sweden)

    Carolina Doya

    Full Text Available Knowledge of the processes shaping deep-sea benthic communities at seasonal scales in cold-seep environments is incomplete. Cold seeps within highly dynamic regions, such as submarine canyons, where variable current regimes may occur, are particularly understudied. Novel Internet Operated Vehicles (IOVs, such as tracked crawlers, provide new techniques for investigating these ecosystems over prolonged periods. In this study a benthic crawler connected to the NEPTUNE cabled infrastructure operated by Ocean Networks Canada was used to monitor community changes across 60 m2 of a cold-seep area of the Barkley Canyon, North East Pacific, at ~890 m depth within an Oxygen Minimum Zone (OMZ. Short video-transects were run at 4-h intervals during the first week of successive calendar months, over a 14 month period (February 14th 2013 to April 14th 2014. Within each recorded transect video megafauna abundances were computed and changes in environmental conditions concurrently measured. The responses of fauna to environmental conditions as a proxy of seasonality were assessed through analysis of abundances in a total of 438 video-transects (over 92 h of total footage. 7698 fauna individuals from 6 phyla (Cnidaria, Ctenophora, Arthropoda, Echinodermata, Mollusca, and Chordata were logged and patterns in abundances of the 7 most abundant taxa (i.e. rockfish Sebastidae, sablefish Anoplopoma fimbria, hagfish Eptatretus stoutii, buccinids (Buccinoidea, undefined small crabs, ctenophores Bolinopsis infundibulum, and Scyphomedusa Poralia rufescens were identified. Patterns in the reproductive behaviour of the grooved tanner crab (Chionnecetes tanneri were also indicated. Temporal variations in biodiversity and abundance in megabenthic fauna was significantly influenced by variabilities in flow velocity flow direction (up or down canyon, dissolved oxygen concentration and month of study. Also reported here for the first time are transient mass aggregations of

  10. Cold and heat waves in the United States.

    Science.gov (United States)

    Barnett, A G; Hajat, S; Gasparrini, A; Rocklöv, J

    2012-01-01

    Extreme cold and heat waves, characterized by a number of cold or hot days in succession, place a strain on people's cardiovascular and respiratory systems. The increase in deaths due to these waves may be greater than that predicted by extreme temperatures alone. We examined cold and heat waves in 99 US cities for 14 years (1987-2000) and investigated how the risk of death depended on the temperature threshold used to define a wave, and a wave's timing, duration and intensity. We defined cold and heat waves using temperatures above and below cold and heat thresholds for two or more days. We tried five cold thresholds using the first to fifth percentiles of temperature, and five heat thresholds using the 95-99 percentiles. The extra wave effects were estimated using a two-stage model to ensure that their effects were estimated after removing the general effects of temperature. The increases in deaths associated with cold waves were generally small and not statistically significant, and there was even evidence of a decreased risk during the coldest waves. Heat waves generally increased the risk of death, particularly for the hottest heat threshold. Cold waves of a colder intensity or longer duration were not more dangerous. Cold waves earlier in the cool season were more dangerous, as were heat waves earlier in the warm season. In general there was no increased risk of death during cold waves above the known increased risk associated with cold temperatures. Cold or heat waves earlier in the cool or warm season may be more dangerous because of a build up in the susceptible pool or a lack of preparedness for extreme temperatures. Copyright © 2011 Elsevier Inc. All rights reserved.

  11. Spatial distribution of cold-season lightning frequency in the coastal areas of the Sea of Japan

    Science.gov (United States)

    Tsurushima, Daiki; Sakaida, Kiyotaka; Honma, Noriyasu

    2017-12-01

    The coastal areas of the Sea of Japan are a well-known hotspot of winter lightning activity. This study distinguishes between three common types of winter lightning in that region (types A-C), based on their frequency distributions and the meteorological conditions under which they occur. Type A lightning occurs with high frequency in the Tohoku district. It is mainly caused by cold fronts that accompany cyclones passing north of the Japanese islands. Type B, which occurs most frequently in the coastal areas of the Hokuriku district, is mainly caused by topographically induced wind convergence and convective instability, both of which are associated with cyclones having multiple centers. Type C's lightning frequency distribution pattern is similar to that of type B, but its principal cause is a topographically induced wind convergence generated by cold air advection from the Siberian continent. Type A is most frequently observed from October to November, while types B and C tend to appear from November to January, consistent with seasonal changes in lightning frequency distribution in Japan's Tohoku and Hokuriku districts.

  12. Methane fluxes during the cold season: distribution and mass transfer in the snow cover of bogs

    Science.gov (United States)

    Smagin, A. V.; Shnyrev, N. A.

    2015-08-01

    Fluxes and profile distribution of methane in the snow cover and different landscape elements of an oligotrophic West-Siberian bog (Mukhrino Research Station, Khanty-Mansiisk autonomous district) have been studied during a cold season. Simple models have been proposed for the description of methane distribution in the inert snow layer, which combine the transport of the gas and a source of constant intensity on the soil surface. The formation rates of stationary methane profiles in the snow cover have been estimated (characteristic time of 24 h). Theoretical equations have been derived for the calculation of small emission fluxes from bogs to the atmosphere on the basis of the stationary profile distribution parameters, the snow porosity, and the effective methane diffusion coefficient in the snow layer. The calculated values of methane emission significantly (by 2-3 to several tens of times) have exceeded the values measured under field conditions by the closed chamber method (0.008-0.25 mg C/(m2 h)), which indicates the possibility of underestimating the contribution of the cold period to the annual emission cycle of bog methane.

  13. The Effect of Soil Temperature Seasonality on Climate Reconstructions from Paleosols

    Science.gov (United States)

    Gallagher, T. M.; Hren, M. T.; Sheldon, N. D.

    2017-12-01

    Accurate continental temperature reconstructions provide important constraints on climate sensitivity to changes in atmospheric pCO2, the timing and rates of tectonic uplift, and the driving mechanisms and feedbacks associated with major climate events. Temperature seasonality is an important variable to consider, because not only does it exert a strong control on the biosphere, but it can obfuscate changes in mean annual air temperature (MAAT) in the geologic record. In order to better understand the effect temperature seasonality has on paleosol temperature proxies, soil temperature data was compiled from over 200 stations that comprise the NCDC Soil Climate Analysis Network. Observed soil temperature variations were then compared to predicted soil temperature values based on normal seasonal air temperature trends. Approximately one quarter of sites record less temperature variation than predicted. This reduction in soil temperature seasonality is a result of warmer than predicted cold-season temperatures, driven by cold-season processes such as snow cover insulation. The reduction in soil temperature seasonality explains why pedo-transfer functions to break down below MAAT values of 6-8 °C. Greater than predicted soil temperature seasonality is observed at nearly half of the sites, driven primarily by direct heating of the soil surface by solar radiation. Deviations larger than 2 °C are not common until mean annual precipitation falls below 300 mm, suggesting that complications introduced by ground heating are primarily restricted to paleosols that formed in more arid environments. Clumped isotope measurements of pedogenic carbonate and bulk paleosol elemental data from a stacked series of paleosols spanning the Eocene-Oligocene in Northeastern Spain are also examined to demonstrate how the documented seasonal trends in modern soils can help inform paleo-applications.

  14. The effect of seasonality on burn incidence, severity and outcome in Central Malawi.

    Science.gov (United States)

    Tyson, Anna F; Gallaher, Jared; Mjuweni, Stephen; Cairns, Bruce A; Charles, Anthony G

    2017-08-01

    In much of the world, burns are more common in cold months. However, few studies have described the seasonality of burns in sub-Saharan Africa. This study examines the effect of seasonality on the incidence and outcome of burns in central Malawi. A retrospective analysis was performed at Kamuzu Central Hospital and included all patients admitted from May 2011 to August 2014. Demographic data, burn mechanism, total body surface area (%TBSA), and mortality were analyzed. Seasons were categorized as Rainy (December-February), Lush (March-May), Cold (June-August) and Hot (September-November). A negative binomial regression was used to assess the effect of seasonality on burn incidence. This was performed using both the raw and deseasonalized data in order to evaluate for trends not attributable to random fluctuation. A total of 905 patients were included. Flame (38%) and Scald (59%) burns were the most common mechanism. More burns occurred during the cold season (41% vs 19-20% in the other seasons). Overall mortality was 19%. Only the cold season had a statistically significant increase in burn . The incidence rate ratios (IRR) for the hot, lush, and cold seasons were 0.94 (CI 0.6-1.32), 1.02 (CI 0.72-1.45) and 1.6 (CI 1.17-2.19), respectively, when compared to the rainy season. Burn severity and mortality did not differ between seasons. The results of this study demonstrate the year-round phenomenon of burns treated at our institution, and highlights the slight predominance of burns during the cold season. These data can be used to guide prevention strategies, with special attention to the implications of the increased burn incidence during the cold season. Though burn severity and mortality remain relatively unchanged between seasons, recognizing the seasonal variability in incidence of burns is critical for resource allocation in this low-income setting. Copyright © 2017 Elsevier Ltd and ISBI. All rights reserved.

  15. Are cold winters in Europe associated with low solar activity?

    International Nuclear Information System (INIS)

    Lockwood, M; Harrison, R G; Woollings, T; Solanki, S K

    2010-01-01

    Solar activity during the current sunspot minimum has fallen to levels unknown since the start of the 20th century. The Maunder minimum (about 1650-1700) was a prolonged episode of low solar activity which coincided with more severe winters in the United Kingdom and continental Europe. Motivated by recent relatively cold winters in the UK, we investigate the possible connection with solar activity. We identify regionally anomalous cold winters by detrending the Central England temperature (CET) record using reconstructions of the northern hemisphere mean temperature. We show that cold winter excursions from the hemispheric trend occur more commonly in the UK during low solar activity, consistent with the solar influence on the occurrence of persistent blocking events in the eastern Atlantic. We stress that this is a regional and seasonal effect relating to European winters and not a global effect. Average solar activity has declined rapidly since 1985 and cosmogenic isotopes suggest an 8% chance of a return to Maunder minimum conditions within the next 50 years (Lockwood 2010 Proc. R. Soc. A 466 303-29): the results presented here indicate that, despite hemispheric warming, the UK and Europe could experience more cold winters than during recent decades.

  16. Detecting the permafrost carbon feedback: talik formation and increased cold-season respiration as precursors to sink-to-source transitions

    Science.gov (United States)

    Parazoo, Nicholas C.; Koven, Charles D.; Lawrence, David M.; Romanovsky, Vladimir; Miller, Charles E.

    2018-01-01

    source early (late 21st century), emits 5 times more C (95 Pg C) by 2300, and prior to talik formation due to the high decomposition rates of shallow, young C in organic-rich soils coupled with low productivity. Our results provide important clues signaling imminent talik onset and C source transition, including (1) late cold-season (January-February) soil warming at depth ( ˜ 2 m), (2) increasing cold-season emissions (November-April), and (3) enhanced respiration of deep, old C in warm permafrost and young, shallow C in organic-rich cold permafrost soils. Our results suggest a mosaic of processes that govern carbon source-to-sink transitions at high latitudes and emphasize the urgency of monitoring soil thermal profiles, organic C age and content, cold-season CO2 emissions, and atmospheric 14CO2 as key indicators of the permafrost C feedback.

  17. Evaluating sub-seasonal skill in probabilistic forecasts of Atmospheric Rivers and associated extreme events

    Science.gov (United States)

    Subramanian, A. C.; Lavers, D.; Matsueda, M.; Shukla, S.; Cayan, D. R.; Ralph, M.

    2017-12-01

    Atmospheric rivers (ARs) - elongated plumes of intense moisture transport - are a primary source of hydrological extremes, water resources and impactful weather along the West Coast of North America and Europe. There is strong demand in the water management, societal infrastructure and humanitarian sectors for reliable sub-seasonal forecasts, particularly of extreme events, such as floods and droughts so that actions to mitigate disastrous impacts can be taken with sufficient lead-time. Many recent studies have shown that ARs in the Pacific and the Atlantic are modulated by large-scale modes of climate variability. Leveraging the improved understanding of how these large-scale climate modes modulate the ARs in these two basins, we use the state-of-the-art multi-model forecast systems such as the North American Multi-Model Ensemble (NMME) and the Subseasonal-to-Seasonal (S2S) database to help inform and assess the probabilistic prediction of ARs and related extreme weather events over the North American and European West Coasts. We will present results from evaluating probabilistic forecasts of extreme precipitation and AR activity at the sub-seasonal scale. In particular, results from the comparison of two winters (2015-16 and 2016-17) will be shown, winters which defied canonical El Niño teleconnection patterns over North America and Europe. We further extend this study to analyze probabilistic forecast skill of AR events in these two basins and the variability in forecast skill during certain regimes of large-scale climate modes.

  18. The influence of the bottom cold water on the seasonal variability of the Tsushima warm current

    Science.gov (United States)

    Isobe, Atsuhiko

    1995-06-01

    Previous studies have concluded that the volume transport and surface current velocity of the Tsushima Warm Current are at a maximum between summer and autumn and at a minimum between winter and spring. Each study has obtained these results indirectly, using the sea level difference across the Tsushima-Korea Strait or dynamic calculation. Numerical experiments are performed to estimate the seasonal variability in the sea level difference caused by the Bottom Cold Water (BCW), which intrudes from the Sea of Japan along the Korean coast in the bottom layer. These experiments basically treat the baroclinic adjustment problem of the BCW in a rectangular cross section perpendicular to the axis (northeast-southwest direction) of the Tsushima-Korea Strait. It is a five-layer model for summer and a two-layer model for winter. The initial conditions and parameters in models are chosen so as to match the calculated velocity-density fields with the observed velocity-density fields [Isobe A., S. Tawara, A. Kaneko and M. Kawano (1994) Continental Shelf Research, 14, 23-35.]. Consequently, the experiments prove that the observed seasonal variability in the sea level difference across the Tsushima-Korea Strait largely contains the baroclinic motion caused by the BCW. It should be noted that the position of the BCW also plays an important role in producing a considerable seasonal variation of the sea level difference. It is critical to remove the baroclinic contribution from the observed sea level differences across the Tsushima-Korea Strait in order to estimate the seasonal variation in the volume transport of the Tsushima Warm Current.

  19. Rubber trees demonstrate a clear retranslocation under seasonal drought and cold stresses

    Directory of Open Access Journals (Sweden)

    Yuwu Li

    2016-12-01

    Full Text Available Having been introduced to the northern edge of Asian tropics, the rubber tree (Hevea brasiliensis has become deciduous in this climate with seasonal drought and cold stresses. To determine its internal nutrient strategy during leaf senescence and deciduous periods, we investigated mature leaf and senescent leaf nutrients, water-soluble soil nutrients and characteristics of soil microbiota in nine different ages of monoculture rubber plantations. Rubber trees demonstrate complicated retranslocation of N, P and K during foliar turnover. Approximately 50.26% of leaf nutrients and 21.47% of soil nutrients were redistributed to the rubber tree body during the leaf senescence and withering stages. However, no significant changes in the structure- or function-related properties of soil microbes were detected. These nutrient retranslocation strategy may be important stress responses. In the nutrient retranslocation process, soil plays a dual role as nutrient supplier and nutrient bank. Soil received the nutrients from abscissed leaves, and also supplied nutrients to trees in the non-growth stage. Nutrient absorption and accumulation began before the leaves started to wither and fall.

  20. Detecting the permafrost carbon feedback: talik formation and increased cold-season respiration as precursors to sink-to-source transitions

    Directory of Open Access Journals (Sweden)

    N. C. Parazoo

    2018-01-01

    remaining C source region in cold northern Arctic permafrost, which shifts to a net source early (late 21st century, emits 5 times more C (95 Pg C by 2300, and prior to talik formation due to the high decomposition rates of shallow, young C in organic-rich soils coupled with low productivity. Our results provide important clues signaling imminent talik onset and C source transition, including (1 late cold-season (January–February soil warming at depth ( ∼  2 m, (2 increasing cold-season emissions (November–April, and (3 enhanced respiration of deep, old C in warm permafrost and young, shallow C in organic-rich cold permafrost soils. Our results suggest a mosaic of processes that govern carbon source-to-sink transitions at high latitudes and emphasize the urgency of monitoring soil thermal profiles, organic C age and content, cold-season CO2 emissions, and atmospheric 14CO2 as key indicators of the permafrost C feedback.

  1. The impact of cold spells on mortality and effect modification by cold spell characteristics

    Science.gov (United States)

    Wang, Lijun; Liu, Tao; Hu, Mengjue; Zeng, Weilin; Zhang, Yonghui; Rutherford, Shannon; Lin, Hualiang; Xiao, Jianpeng; Yin, Peng; Liu, Jiangmei; Chu, Cordia; Tong, Shilu; Ma, Wenjun; Zhou, Maigeng

    2016-12-01

    In China, the health impact of cold weather has received little attention, which limits our understanding of the health impacts of climate change. We collected daily mortality and meteorological data in 66 communities across China from 2006 to 2011. Within each community, we estimated the effect of cold spell exposure on mortality using a Distributed Lag Nonlinear Model (DLNM). We also examined the modification effect of cold spell characteristics (intensity, duration, and timing) and individual-specific factors (causes of death, age, gender and education). Meta-analysis method was finally used to estimate the overall effects. The overall cumulative excess risk (CER) of non-accidental mortality during cold spell days was 28.2% (95% CI: 21.4%, 35.3%) compared with non-cold spell days. There was a significant increase in mortality when the cold spell duration and intensity increased or occurred earlier in the season. Cold spell effects and effect modification by cold spell characteristics were more pronounced in south China. The elderly, people with low education level and those with respiratory diseases were generally more vulnerable to cold spells. Cold spells statistically significantly increase mortality risk in China, with greater effects in southern China. This effect is modified by cold spell characteristics and individual-level factors.

  2. Extreme Temperature Regimes during the Cool Season and their Associated Large-Scale Circulations

    Science.gov (United States)

    Xie, Z.

    2015-12-01

    In the cool season (November-March), extreme temperature events (ETEs) always hit the continental United States (US) and provide significant societal impacts. According to the anomalous amplitudes of the surface air temperature (SAT), there are two typical types of ETEs, e.g. cold waves (CWs) and warm waves (WWs). This study used cluster analysis to categorize both CWs and WWs into four distinct regimes respectively and investigated their associated large-scale circulations on intra-seasonal time scale. Most of the CW regimes have large areal impact over the continental US. However, the distribution of cold SAT anomalies varies apparently in four regimes. In the sea level, the four CW regimes are characterized by anomalous high pressure over North America (near and to west of cold anomaly) with different extension and orientation. As a result, anomalous northerlies along east flank of anomalous high pressure convey cold air into the continental US. To the middle troposphere, the leading two groups feature large-scale and zonally-elongated circulation anomaly pattern, while the other two regimes exhibit synoptic wavetrain pattern with meridionally elongated features. As for the WW regimes, there are some patterns symmetry and anti-symmetry with respect to CW regimes. The WW regimes are characterized by anomalous low pressure and southerlies wind over North America. The first and fourth groups are affected by remote forcing emanating from North Pacific, while the others appear mainly locally forced.

  3. The impact of MIS-3 climate events at the transition from Neanderthals to modern humans in Europe

    Science.gov (United States)

    Staubwasser, M.; Dragusin, V.; Assonov, S.; Ersek, V.; Hoffmann, D.; Veres, D.; Onac, B. P.

    2017-12-01

    We report on last glacial stable C and O isotope records from two U-Th dated speleothems from Romania. The southerly record (Ascunsa Cave, South Carpathians) from the Danube region matches the pacing and relative change in amplitude of the Greenland ice temperature record at 30-50 ka BP as well as the abundance of coastal winter sea ice in the Black Sea. The northerly record (Tausoare Cave, East Carpathians) in parts shares the pacing of events with the Greenland or the southern Romanian record, but best matches northern Black Sea summer season temperature change. Heinrich events do not stand out in either record, but the temperature amplitudes of Greenland stadials and Black Sea records are generally reproduced. Based on similarity with the Black Sea we interpret the combined two speleothem records in terms of seasonal temperature change in central Eastern Europe. A climatic influence on the transition from Neanderthals to modern humans has long been suspected. However, the diachronous and spatially complex archaeologic succession across the Middle-Upper Paleolithic (MUPL) in Europe ( 38 - 48 ka) is difficult to reconcile with the millennial-scale pacing of northern hemisphere paleoclimate. Two extreme cold events at 44.0-43.3 recorded and 40.7-39.8 ka in the speleothems bracket the dates of the first known appearance of modern humans - the Aurignacian complex - and the disappearance of Neanderthals from most of Europe. These cold events are coeval with Greenland Stadials GS-12 and GS-10. The speleothem records generally match the paleosol/loess succession from central Europe across the MUPL. The combined record suggests that permafrost advance may have made central Europe uninhabitable at least during winter. The combined paleoclimate and archaeologic records suggest that depopulation-repopulation cycles may have occurred during and after each cold event. Repopulation of central Europe geographically favored the modern human Aurignacians from SE Europe.

  4. Cold thermal injury from cold caps used for the prevention of chemotherapy-induced alopecia.

    Science.gov (United States)

    Belum, Viswanath Reddy; de Barros Silva, Giselle; Laloni, Mariana Tosello; Ciccolini, Kathryn; Goldfarb, Shari B; Norton, Larry; Sklarin, Nancy T; Lacouture, Mario E

    2016-06-01

    The use of scalp cooling for the prevention of chemotherapy-induced alopecia (CIA) is increasing. Cold caps are placed onto the hair-bearing areas of the scalp for varying time periods before, during, and after cytotoxic chemotherapy. Although not yet reported, improper application procedures could result in adverse events (AEs). At present, there are no evidence-based scalp cooling protocols, and there is no regulatory oversight of their use. To report the occurrence of cold thermal injury (frostbite) on the scalp, following the use of cold caps for the prevention of CIA. We identified four patients who developed cold thermal injuries on the scalp following the application of cold caps. Medical records were analyzed to retrieve the demographic and clinical characteristics. The cold thermal injuries in our patients were grade 1/2 in severity and improved with topical interventions and interruption of cold cap use, although grade 1 persistent alopecia ensued in 3 patients. The true incidence of such injuries in this setting, however, remains unknown. Cold thermal injuries are likely infrequent and preventable AEs that may result from improper device application procedures during cold cap use. Although these untoward events are usually mild to moderate in severity, the potential occurrence of long-term sequelae (e.g., permanent alopecia and scarring) or the need to discontinue cold cap use, are not known. Prospective studies are needed to further elucidate the risk and standardize healthcare delivery methods, and to improve patient/supportive/healthcare provider education.

  5. The Dependency between the Arabian Peninsula Wet Events and Sea Level Pressure Patterns during Spring Season

    KAUST Repository

    El Kenawy, Ahmed M.; McCabe, Matthew; Stenchikov, Georgiy L.; Raj, Jerry

    2014-01-01

    This work investigates the relationships between regional extreme wet events in the Arabian Peninsula during the spring season (MAM) and sea level pressure (SLP) patterns. Based on NCEP/NCAR reanalysis data, S-mode principal components were computed

  6. Long-range transport of Asian pollution to the northeast Pacific: Seasonal variations and transport pathways of carbon monoxide

    Science.gov (United States)

    Liang, Qing; Jaeglé, Lyatt; Jaffe, Daniel A.; Weiss-Penzias, Peter; Heckman, Anna; Snow, Julie A.

    2004-12-01

    Continuous CO measurements were obtained at Cheeka Peak Observatory (CPO, 48.3°N, 124.6°W, 480 m), a coastal site in Washington state, between 9 March 2001 and 31 May 2002. We analyze these observations as well as CO observations at ground sites throughout the North Pacific using the GEOS-CHEM global tropospheric chemistry model to examine the seasonal variations of Asian long-range transport. The model reproduces the observed CO levels, their seasonal cycle and day-to-day variability, with a 5-20 ppbv negative bias in winter/spring and 5-10 ppbv positive bias during summer. Asian influence on CO levels in the North Pacific troposphere maximizes during spring and minimizes during summer, ranging from 91 ppbv (44% of total CO) to 52 ppbv (39%) along the Asian Pacific Rim and from 44 ppbv (30%) to 24 ppbv (23%) at CPO. Maximum export of Asian pollution to the western Pacific occurs at 20°-50°N during spring throughout the tropospheric column, shifting to 30°-60°N during summer, mostly in the upper troposphere. The model captures five particularly strong transpacific transport events reaching CPO (four in spring, one in winter) resulting in 20-40 ppbv increases in observed CO levels. Episodic long-range transport of pollutants from Asia to the NE Pacific occurs throughout the year every 10, 15, and 30 days in the upper, middle, and lower troposphere, respectively. Lifting ahead of cold fronts followed by transport in midlatitude westerlies accounts for 78% of long-range transport events reaching the NE Pacific middle and upper troposphere. During summer, convective injection into the upper troposphere competes with frontal mechanisms in this export. Most events reaching the NE Pacific lower troposphere below 2 km altitude result from boundary layer outflow behind cold fronts (for spring) or ahead of cold fronts (for other seasons) followed by low-level transpacific transport.

  7. Attribution of extreme weather and climate-related events.

    Science.gov (United States)

    Stott, Peter A; Christidis, Nikolaos; Otto, Friederike E L; Sun, Ying; Vanderlinden, Jean-Paul; van Oldenborgh, Geert Jan; Vautard, Robert; von Storch, Hans; Walton, Peter; Yiou, Pascal; Zwiers, Francis W

    2016-01-01

    Extreme weather and climate-related events occur in a particular place, by definition, infrequently. It is therefore challenging to detect systematic changes in their occurrence given the relative shortness of observational records. However, there is a clear interest from outside the climate science community in the extent to which recent damaging extreme events can be linked to human-induced climate change or natural climate variability. Event attribution studies seek to determine to what extent anthropogenic climate change has altered the probability or magnitude of particular events. They have shown clear evidence for human influence having increased the probability of many extremely warm seasonal temperatures and reduced the probability of extremely cold seasonal temperatures in many parts of the world. The evidence for human influence on the probability of extreme precipitation events, droughts, and storms is more mixed. Although the science of event attribution has developed rapidly in recent years, geographical coverage of events remains patchy and based on the interests and capabilities of individual research groups. The development of operational event attribution would allow a more timely and methodical production of attribution assessments than currently obtained on an ad hoc basis. For event attribution assessments to be most useful, remaining scientific uncertainties need to be robustly assessed and the results clearly communicated. This requires the continuing development of methodologies to assess the reliability of event attribution results and further work to understand the potential utility of event attribution for stakeholder groups and decision makers. WIREs Clim Change 2016, 7:23-41. doi: 10.1002/wcc.380 For further resources related to this article, please visit the WIREs website.

  8. Seasonality in acute liver injury? Findings in two health care claims databases

    Directory of Open Access Journals (Sweden)

    Weinstein RB

    2016-03-01

    Full Text Available Rachel B Weinstein, Martijn J Schuemie, Patrick B Ryan, Paul E Stang Epidemiology, Janssen Research and Development, LLC, Titusville, NJ, USA Background: Presumed seasonal use of acetaminophen-containing products for relief of cold/influenza (“flu” symptoms suggests that there might also be a corresponding seasonal pattern for acute liver injury (ALI, a known clinical consequence of acetaminophen overdose. Objective: The objective of this study was to determine whether there were any temporal patterns in hospitalizations for ALI that would correspond to assumed acetaminophen use in cold/flu season. Methods: In the period 2002–2010, monthly hospitalization rates for ALI using a variety of case definitions were calculated. Data sources included Truven MarketScan® Commercial Claims and Encounters (CCAE and Medicare Supplemental and Coordination of Benefits (MDCR databases. We performed a statistical test for seasonality of diagnoses using the periodic generalized linear model. To validate that the test can distinguish seasonal from nonseasonal patterns, we included two positive controls (ie, diagnoses of the common cold [acute nasopharyngitis] and influenza, believed to change with seasons, and two negative controls (female breast cancer and diabetes, believed to be insensitive to season. Results: A seasonal pattern was observed in monthly rates for common cold and influenza diagnoses, but this pattern was not observed for monthly rates of ALI, with or without comorbidities (cirrhosis or hepatitis, breast cancer, or diabetes. The statistical test for seasonality was significant for positive controls (P<0.001 for each diagnosis in both databases and nonsignificant for ALI and negative controls. Conclusion: No seasonal pattern was observed in the diagnosis of ALI. The positive and negative controls showed the expected patterns, strengthening the validity of the statistical and visual tests used for detecting seasonality. Keywords: acute liver

  9. Heterologous microarray experiments allow the identification of the early events associated with potato tuber cold sweetening

    Directory of Open Access Journals (Sweden)

    Vitulli Federico

    2008-04-01

    Full Text Available Abstract Background Since its discovery more than 100 years ago, potato (Solanum tuberosum tuber cold-induced sweetening (CIS has been extensively investigated. Several carbohydrate-associated genes would seem to be involved in the process. However, many uncertainties still exist, as the relative contribution of each gene to the process is often unclear, possibly as the consequence of the heterogeneity of experimental systems. Some enzymes associated with CIS, such as β-amylases and invertases, have still to be identified at a sequence level. In addition, little is known about the early events that trigger CIS and on the involvement/association with CIS of genes different from carbohydrate-associated genes. Many of these uncertainties could be resolved by profiling experiments, but no GeneChip is available for the potato, and the production of the potato cDNA spotted array (TIGR has recently been discontinued. In order to obtain an overall picture of early transcriptional events associated with CIS, we investigated whether the commercially-available tomato Affymetrix GeneChip could be used to identify which potato cold-responsive gene family members should be further studied in detail by Real-Time (RT-PCR (qPCR. Results A tomato-potato Global Match File was generated for the interpretation of various aspects of the heterologous dataset, including the retrieval of best matching potato counterparts and annotation, and the establishment of a core set of highly homologous genes. Several cold-responsive genes were identified, and their expression pattern was studied in detail by qPCR over 26 days. We detected biphasic behaviour of mRNA accumulation for carbohydrate-associated genes and our combined GeneChip-qPCR data identified, at a sequence level, enzymatic activities such as β-amylases and invertases previously reported as being involved in CIS. The GeneChip data also unveiled important processes accompanying CIS, such as the induction of redox

  10. NETmundial: only a landmark event if 'Digital Cold War' rhetoric abandoned

    Directory of Open Access Journals (Sweden)

    Francesca Musiani

    2014-03-01

    Full Text Available While internet privacy has been a central concern for quite a long time, the revelations by Edward Snowden about the US National Security Agency’s massive surveillance programme have highlighted the extent to which it is a core political issue. The privacy-surveillance controversy has prompted what is perhaps the most prominent and ambitious call in internet governance history to break the dominance of the United States' control over internet infrastructure: the Global Multistakeholder Meeting on the Future of Internet Governance, or NETmundial (April 2014. The article analyses the current state of multi-stakeholderism in internet governance in light of this event. In particular, it argues for the necessity to leave the ‘Digital Cold War’ rhetoric behind if the internationalisation and the globalisation of internet governance is to move to the next level.

  11. Latitudinal Patterns in European Seagrass Carbon Reserves: Influence of Seasonal Fluctuations versus Short-Term Stress and Disturbance Events

    Directory of Open Access Journals (Sweden)

    Laura M. Soissons

    2018-02-01

    Full Text Available Seagrass meadows form highly productive and valuable ecosystems in the marine environment. Throughout the year, seagrass meadows are exposed to abiotic and biotic variations linked to (i seasonal fluctuations, (ii short-term stress events such as, e.g., local nutrient enrichment, and (iii small-scale disturbances such as, e.g., biomass removal by grazing. We hypothesized that short-term stress events and small-scale disturbances may affect seagrass chance for survival in temperate latitudes. To test this hypothesis we focused on seagrass carbon reserves in the form of starch stored seasonally in rhizomes, as these have been defined as a good indicator for winter survival. Twelve Zostera noltei meadows were monitored along a latitudinal gradient in Western Europe to firstly assess the seasonal change of their rhizomal starch content. Secondly, we tested the effects of nutrient enrichment and/or biomass removal on the corresponding starch content by using a short-term manipulative field experiment at a single latitude in the Netherlands. At the end of the growing season, we observed a weak but significant linear increase of starch content along the latitudinal gradient from south to north. This agrees with the contention that such reserves are essential for regrowth after winter, which is more severe in the north. In addition, we also observed a weak but significant positive relationship between starch content at the beginning of the growing season and past winter temperatures. This implies a lower regrowth potential after severe winters, due to diminished starch content at the beginning of the growing season. Short-term stress and disturbances may intensify these patterns, because our manipulative experiments show that when nutrient enrichment and biomass loss co-occurred at the end of the growing season, Z. noltei starch content declined. In temperate zones, the capacity of seagrasses to accumulate carbon reserves is expected to determine carbon

  12. Latitudinal Patterns in European Seagrass Carbon Reserves: Influence of Seasonal Fluctuations versus Short-Term Stress and Disturbance Events

    Science.gov (United States)

    Soissons, Laura M.; Haanstra, Eeke P.; van Katwijk, Marieke M.; Asmus, Ragnhild; Auby, Isabelle; Barillé, Laurent; Brun, Fernando G.; Cardoso, Patricia G.; Desroy, Nicolas; Fournier, Jerome; Ganthy, Florian; Garmendia, Joxe-Mikel; Godet, Laurent; Grilo, Tiago F.; Kadel, Petra; Ondiviela, Barbara; Peralta, Gloria; Puente, Araceli; Recio, Maria; Rigouin, Loic; Valle, Mireia; Herman, Peter M. J.; Bouma, Tjeerd J.

    2018-01-01

    Seagrass meadows form highly productive and valuable ecosystems in the marine environment. Throughout the year, seagrass meadows are exposed to abiotic and biotic variations linked to (i) seasonal fluctuations, (ii) short-term stress events such as, e.g., local nutrient enrichment, and (iii) small-scale disturbances such as, e.g., biomass removal by grazing. We hypothesized that short-term stress events and small-scale disturbances may affect seagrass chance for survival in temperate latitudes. To test this hypothesis we focused on seagrass carbon reserves in the form of starch stored seasonally in rhizomes, as these have been defined as a good indicator for winter survival. Twelve Zostera noltei meadows were monitored along a latitudinal gradient in Western Europe to firstly assess the seasonal change of their rhizomal starch content. Secondly, we tested the effects of nutrient enrichment and/or biomass removal on the corresponding starch content by using a short-term manipulative field experiment at a single latitude in the Netherlands. At the end of the growing season, we observed a weak but significant linear increase of starch content along the latitudinal gradient from south to north. This agrees with the contention that such reserves are essential for regrowth after winter, which is more severe in the north. In addition, we also observed a weak but significant positive relationship between starch content at the beginning of the growing season and past winter temperatures. This implies a lower regrowth potential after severe winters, due to diminished starch content at the beginning of the growing season. Short-term stress and disturbances may intensify these patterns, because our manipulative experiments show that when nutrient enrichment and biomass loss co-occurred at the end of the growing season, Z. noltei starch content declined. In temperate zones, the capacity of seagrasses to accumulate carbon reserves is expected to determine carbon-based regrowth

  13. Crosstalk of PmCBFs and PmDAMs Based on the Changes of Phytohormones under Seasonal Cold Stress in the Stem of Prunus mume

    Directory of Open Access Journals (Sweden)

    Kai Zhao

    2018-01-01

    Full Text Available Plants facing the seasonal variations always need a growth restraining mechanism when temperatures turn down. C-repeat binding factor (CBF genes work essentially in the cold perception. Despite lots of researches on CBFs, the multiple crosstalk is still interesting on their interaction with hormones and dormancy-associated MADS (DAM genes in the growth and dormancy control. Therefore, this study highlights roles of PmCBFs in cold-induced dormancy from different orgens. And a sense-response relationship between PmCBFs and PmDAMs is exhibited in this process, jointly regulated by six PmCBFs and PmDAM4–6. Meantime, GA3 and ABA showed negative and positive correlation with PmCBFs expression levels, respectively. We also find a high correlation between IAA and PmDAM1–3. Finally, we display the interaction mode of PmCBFs and PmDAMs, especially PmCBF1-PmDAM1. These results can disclose another view of molecular mechanism in plant growth between cold-response pathway and dormancy regulation together with genes and hormones.

  14. Altered structural development and accelerated succession from intermediate-scale wind disturbance in Quercus stands on the Cumberland Plateau, USA

    Science.gov (United States)

    Stephen D White; Justin L. Hart; Callie J. Schweitzer; Daniel C. Dey

    2015-01-01

    Natural disturbances play important roles in shaping the structure and composition of all forest ecosystems and can be used to inform silvicultural practices. Canopy disturbances are often classified along a gradient ranging from highly localized, gap-scale events to stand-replacing events. Wind storms such as downbursts, derechos, and low intensity tornadoes typically...

  15. Recent Intensified Winter Coldness in the Mid-High Latitudes of Eurasia and Its Relationship with Daily Extreme Low Temperature Variability

    Directory of Open Access Journals (Sweden)

    Chuhan Lu

    2016-01-01

    Full Text Available Observational records in recent decades show a large-scale decrease in the cold-season temperature variance in the Northern Hemisphere midlatitudes under continuous global warming. However, severe low temperature events in winter frequently occurred in midlatitude Eurasia (MEA in the last decade. Here, we define a new coldness intensity (CI index for the near-surface based on the amplitude of daily anomalously cold temperatures in winter to demonstrate the CI of the variability of low temperature extremes. The results show that a sign-consistent mode dominates the CI variation in MEA, with a marked intensification during the last decade via empirical orthogonal function (EOF analysis. This leading mode is significantly related to the frequency of winter extreme events. The associated circulations are characterized by a remarkable anomalous anticyclone in Northwest Eurasia, which induced substantial cold advection in MEA. The widespread intensified CI in MEA is closely linked with strong surface anticyclones and synoptic blocking in the mid-high latitudes (25°E–85°E. Coincidently, positive phase shifts of the first two leading modes of the extratropical circulation, which feature similar blocking-like anomalies in the northwestern Eurasian subarctic, jointly play an important role in the recent frequency of severe winters.

  16. Adverse events associated with opioid-containing cough and cold medications in children.

    Science.gov (United States)

    Paul, Ian M; Reynolds, Kate M; Green, Jody L

    2018-04-10

    Until recently most of the scrutiny of opioid-containing cough and cold medications (CCMs) by the US Food and Drug Administration (FDA) was focused on codeine, only recently shifting equal focus to those containing hydrocodone. We characterized adverse events (AEs) in children Dictionary for Regulatory Activities with preferred terms reported. One hundred and fourteen of the 7035 (2%) cases reviewed involved an opioid-containing product. Ninety-eight cases involved an AE at least potentially related to the opioid ingredient (38 (39%) codeine; 60 (61%) hydrocodone). All three fatality cases involved hydrocodone with an antihistamine. Among non-fatalities, somnolence, lethargy, and/or respiratory depression were more commonly reported among hydrocodone cases than codeine cases (86% vs. 61%; p = .005). These safety surveillance data support the FDA's expanded label changes limiting opioid CCMs for children.

  17. The Dependency between the Arabian Peninsula Wet Events and Sea Level Pressure Patterns during Spring Season

    KAUST Repository

    El Kenawy, Ahmed M.

    2014-05-01

    This work investigates the relationships between regional extreme wet events in the Arabian Peninsula during the spring season (MAM) and sea level pressure (SLP) patterns. Based on NCEP/NCAR reanalysis data, S-mode principal components were computed from the de-seasonalized daily SLP for spring months between 1960 and 2013. The analysis covered a window for the region (15-70°E and 2.5-50°N). This window coupled different oceanic-land influences (e.g. the Indian, Mediterranean and the Sahara configurations) that may impart an effect on rainfall variations in the study domain. A set of eight significant circulation spatial patterns were retained, which explained 84.8% of the total explained variance. The derived patterns explained a wide variety of flows over the peninsula, with a clear distinction between zonal and meridional advections. The extreme wet events (R95 and R99) were defined from a relatively dense network of 209 observatories covering the peninsula, using the 95th and 99th percentile of rainfall distribution respectively. The links between the dominant SLP patterns and significant wet events were established and the physical interpretations of these associations were examined. The results, as revealed by the location and intensity of high pressure centers, highlight the strength of eastern and southeastern advections corresponding to these extreme events. Other patterns have a local character, suggesting an orographic origin of some wet events in the region. The relationships described in this research can advance the understanding of the large-scale processes that contribute to the wet weather events in the Arabian Peninsula. These findings can therefore contribute to better management of water resources and agricultural practices in the region.

  18. Tree-ring based reconstruction of the seasonal timing, major events and origin of rockfall on a case-study slope in the Swiss Alps

    Directory of Open Access Journals (Sweden)

    D. M. Schneuwly

    2008-03-01

    Full Text Available Tree-ring analysis has been used to reconstruct 22 years of rockfall behavior on an active rockfall slope near Saas Balen (Swiss Alps. We analyzed 32 severely injured trees (L. decidua, P. abies and P. cembra and investigated cross-sections of 154 wounds.

    The intra-annual position of callus tissue and of tangential rows of traumatic resin ducts was determined in order to reconstruct the seasonality of past rockfall events. Results indicate strong intra- and inter-annual variations of rockfall activity, with a peak (76% observed in the dormant season (early October – end of May. Within the growth season, rockfall regularly occurs between the end of May and mid July (21.4%, whereas events later in the season appear to be quite rare (2.6%. Findings suggest that rockfall activity at the study site is driven by annual thawing processes and the circulation of melt water in preexisting fissures. Data also indicate that 43% of all rockfall events occurred in 1995, when two major precipitation events are recorded in nearby meteorological stations. Finally, data on impact angles are in very good agreement with the geomorphic situation in the field.

  19. Sub-seasonal Predictability of Heavy Precipitation Events: Implication for Real-time Flood Management in Iran

    Science.gov (United States)

    Najafi, H.; Shahbazi, A.; Zohrabi, N.; Robertson, A. W.; Mofidi, A.; Massah Bavani, A. R.

    2016-12-01

    Each year, a number of high impact weather events occur worldwide. Since any level of predictability at sub-seasonal to seasonal timescale is highly beneficial to society, international efforts is now on progress to promote reliable Ensemble Prediction Systems for monthly forecasts within the WWRP/WCRP initiative (S2S) project and North American Multi Model Ensemble (NMME). For water resources managers in the face of extreme events, not only can reliable forecasts of high impact weather events prevent catastrophic losses caused by floods but also contribute to benefits gained from hydropower generation and water markets. The aim of this paper is to analyze the predictability of recent severe weather events over Iran. Two recent heavy precipitations are considered as an illustration to examine whether S2S forecasts can be used for developing flood alert systems especially where large cascade of dams are in operation. Both events have caused major damages to cities and infrastructures. The first severe precipitation was is in the early November 2015 when heavy precipitation (more than 50 mm) occurred in 2 days. More recently, up to 300 mm of precipitation is observed within less than a week in April 2016 causing a consequent flash flood. Over some stations, the observed precipitation was even more than the total annual mean precipitation. To analyze the predictive capability, ensemble forecasts from several operational centers including (European Centre for Medium-Range Weather Forecasts (ECMWF) system, Climate Forecast System Version 2 (CFSv2) and Chinese Meteorological Center (CMA) are evaluated. It has been observed that significant changes in precipitation anomalies were likely to be predicted days in advance. The next step will be to conduct thorough analysis based on comparing multi-model outputs over the full hindcast dataset developing real-time high impact weather prediction systems.

  20. Spatio-temporal seasonal drought patterns in Europe from 1950 to 2015

    Science.gov (United States)

    Spinoni, Jonathan; Naumann, Gustavo; Vogt, Jürgen

    2016-04-01

    Drought is one of the natural disasters with severe impacts in Europe, not only in areas which frequently experience water scarcity such as the Mediterranean, but also in temperate or continental climates such as Central and Eastern Europe and even in cold regions such as Scandinavia and Iceland. In this study the spatio-temporal patterns of seasonal meteorological droughts in Europe between 1950 and 2015 are investigated using the Standardized Precipitation Index (SPI) and the Standardized Precipitation-Evapotranspiration Index (SPEI). Since the focus is on the analysis of seasonal drought trends, indicators were calculated for 3 monthly accumulation periods. The input variables of precipitation and temperature were derived from E-OBS grids (v11-v12) at a spatial resolution of 0.25°x0.25°. Seasonal trends of drought frequency and severity were analyzed for moderate (SPI or SPEI 2.0) events during the periods 1950-2015 and 1981-2015. For the moderate events, results of the SPI analysis (precipitation driven) demonstrate a significant tendency towards less frequent and severe droughts in Northern Europe and Russia, especially in winter and spring; oppositely, an increasing trend is visible in Southern Europe, mainly in spring and summer. According to the SPEI analysis (precipitation and temperature driven) Northern Europe shows wetting patterns, while Southern and Eastern Europe show a more remarkable drying tendency, especially in summer and autumn for drought frequency and in every season for drought severity. The evolution towards drier conditions is more relevant from 1981 onwards, both in terms of frequency and severity. This is especially true for Central Europe in spring, for the Mediterranean in summer, and for Eastern Europe in autumn. Extreme events follow similar patterns, but in autumn no spatially coherent trend can be found.

  1. Variations in fluid chemistry and membrane phospholipid fatty acid composition of the bacterial community in a cold storage groundwater system during clogging events

    International Nuclear Information System (INIS)

    Vetter, Alexandra; Mangelsdorf, Kai; Wolfgramm, Markus; Rauppach, Kerstin; Schettler, Georg; Vieth-Hillebrand, Andrea

    2012-01-01

    In order to monitor the operating mode of the cold storage of the German Parliament (North German Basin) the fluid chemistry and the phospholipid fatty acid (PLFA) composition of the indigenous microbial community have been monitored from August 2006 to August 2009. During this time two periods of reduced injection (clogging events) characterized by Fe precipitates and microbial biofilms in filters occurred in the injection wells impairing the operating state of the investigated cold storage. The fluid monitoring revealed the presence of sufficient amounts of potential C and energy sources (e.g. DOC and SO 4 2- ) in the process water to sustain microbial life in the cold storage. In times of reduced injection the PLFA inventory of the microbial community differs significantly from times of normal operating phases indicating compositional changes in the indigenous microbial ecosystem. The most affected fatty acids (FAs) are 16:1ω7c (increase), 16:1ω7t (decrease) and 18:1ω7c (increase), interpreted to originate mainly from Fe and S oxidizers, as well as branched FA with 15, 16 and 17 C atoms (decrease) most likely representing sulfate-reducing bacteria (SRB). Based on this variability, PLFA ratios have been created to reflect the increasing dominance of biofilm forming S and Fe oxidizers during the disturbance periods. These ratios are potential diagnostic tools to assess the microbiological contribution to the clogging events and to find appropriate counteractive measures (e.g. mechanical cleaning vs disinfection). The correlation between changes in the PLFA composition and the operational state suggests that microbially mediated processes play a significant role in the observed clogging events in the investigated cold storage.

  2. Aquifer Thermal Energy Storage for Seasonal Thermal Energy Balance

    Science.gov (United States)

    Rostampour, Vahab; Bloemendal, Martin; Keviczky, Tamas

    2017-04-01

    Aquifer Thermal Energy Storage (ATES) systems allow storing large quantities of thermal energy in subsurface aquifers enabling significant energy savings and greenhouse gas reductions. This is achieved by injection and extraction of water into and from saturated underground aquifers, simultaneously. An ATES system consists of two wells and operates in a seasonal mode. One well is used for the storage of cold water, the other one for the storage of heat. In warm seasons, cold water is extracted from the cold well to provide cooling to a building. The temperature of the extracted cold water increases as it passes through the building climate control systems and then gets simultaneously, injected back into the warm well. This procedure is reversed during cold seasons where the flow direction is reversed such that the warmer water is extracted from the warm well to provide heating to a building. From the perspective of building climate comfort systems, an ATES system is considered as a seasonal storage system that can be a heat source or sink, or as a storage for thermal energy. This leads to an interesting and challenging optimal control problem of the building climate comfort system that can be used to develop a seasonal-based energy management strategy. In [1] we develop a control-oriented model to predict thermal energy balance in a building climate control system integrated with ATES. Such a model however cannot cope with off-nominal but realistic situations such as when the wells are completely depleted, or the start-up phase of newly installed wells, etc., leading to direct usage of aquifer ambient temperature. Building upon our previous work in [1], we here extend the mathematical model for ATES system to handle the above mentioned more realistic situations. Using our improved models, one can more precisely predict system behavior and apply optimal control strategies to manage the building climate comfort along with energy savings and greenhouse gas reductions

  3. Exceptional Air Mass Transport and Dynamical Drivers of an Extreme Wintertime Arctic Warm Event

    Science.gov (United States)

    Binder, Hanin; Boettcher, Maxi; Grams, Christian M.; Joos, Hanna; Pfahl, Stephan; Wernli, Heini

    2017-12-01

    At the turn of the years 2015/2016, maximum surface temperature in the Arctic reached record-high values, exceeding the melting point, which led to a strong reduction of the Arctic sea ice extent in the middle of the cold season. Here we show, using a Lagrangian method, that a combination of very different airstreams contributed to this event: (i) warm low-level air of subtropical origin, (ii) initially cold low-level air of polar origin heated by surface fluxes, and (iii) strongly descending air heated by adiabatic compression. The poleward transport of these warm airstreams occurred along an intense low-level jet between a series of cyclones and a quasi-stationary anticyclone. The complex 3-D configuration that enabled this transport was facilitated by continuous warm conveyor belt ascent into the upper part of the anticyclone. This study emphasizes the combined role of multiple transport processes and transient synoptic-scale dynamics for establishing an extreme Arctic warm event.

  4. The response of a simulated mesoscale convective system to increased aerosol pollution: Part II: Derecho characteristics and intensity in response to increased pollution

    Science.gov (United States)

    Clavner, Michal; Grasso, Lewis D.; Cotton, William R.; van den Heever, Susan C.

    2018-01-01

    Mesoscale Convective Systems (MCS) are important contributors to rainfall as well as producers of severe weather such as hail, tornados, and straight-line wind events known as derechos. In this study, different aerosol concentrations and their effects on a derecho event are examined by simulating a case study, the 8 May 2009 "Super-Derecho", using the Regional Atmospheric Modeling System (RAMS), a cloud-resolving model with sophisticated aerosol and cloud microphysics. Three simulations were conducted that differed in the initial aerosol concentrations, spatial distribution and chemical composition as derived from output of GEOS-Chem, a 3D chemical transport model. In order to understand the impact of changes in aerosol concentrations on the derecho characteristics, the dynamical processes that produced the strong surface wind were determined by performing back-trajectory analysis during two periods of the simulated storm: the development and the onset of dissipation. A time dependent and non-monotonic trend was found between the intensity of the derecho and the increased aerosol concentrations that served as cloud condensation nuclei. During the formation period of the MCS, the non-monotonic trend was attributed to the microphysical impact of aerosol loading on the intensity of the cold pool; that is, the impact of aerosols on both the melting and evaporation rates of hydrometeors. The subsequent intensity changes within the cold pool modified the balance between the horizontal vorticity generated by the cold pool and that of the environment, thereby impacting the orientation of the convective updraft at the leading line. This, in turn, altered the primary flow that contributed to the formation of the derecho-strength surface winds. The simulation with no anthropogenic aerosols exhibited the strongest cold pool and the primary flow was associated with a descending rear inflow jet that produced the derecho winds over a larger region. The simulation with the highest

  5. Measurements and Modeling of Turbulent Fluxes during Persistent Cold Air Pool Events in Salt Lake Valley, Utah

    Science.gov (United States)

    Ivey, C. E.; Sun, X.; Holmes, H.

    2017-12-01

    Land surface processes are important in meteorology and climate research since they control the partitioning of surface energy and water exchange at the earth's surface. The surface layer is coupled to the planetary boundary layer (PBL) by surface fluxes, which serve as sinks or sources of energy, moisture, momentum, and atmospheric pollutants. Quantifying the surface heat and momentum fluxes at the land-atmosphere interface, especially for different surface land cover types, is important because they can further influence the atmospheric dynamics, vertical mixing, and transport processes that impact local, regional, and global climate. A cold air pool (CAP) forms when a topographic depression (i.e., valley) fills with cold air, where the air in the stagnant layer is colder than the air aloft. Insufficient surface heating, which is not able to sufficiently erode the temperature inversion that forms during the nighttime stable boundary layer, can lead to the formation of persistent CAPs during wintertime. These persistent CAPs can last for days, or even weeks, and are associated with increased air pollution concentrations. Thus, realistic simulations of the land-atmosphere exchange are meaningful to achieve improved predictions of the accumulation, transport, and dispersion of air pollution concentrations. The focus of this presentation is on observations and modeling results using turbulence data collected in Salt Lake Valley, Utah during the 2010-2011 wintertime Persistent Cold Air Pool Study (PCAPS). Turbulent fluxes and the surface energy balance over seven land use types are quantified. The urban site has an energy balance ratio (EBR) larger than one (1.276). Negative Bowen ratio (-0.070) is found at the cropland site. In addition to turbulence observations, half-hourly WRF simulated net radiation, latent heat, sensible heat, ground heat fluxes during one persistent CAP event are evaluated using the PCAPS observations. The results show that sensible and latent

  6. Seasonal Allergies: Symptoms, Diagnosis, and Treatment | NIH MedlinePlus the Magazine

    Science.gov (United States)

    ... this page please turn Javascript on. Feature: Managing Allergies Seasonal Allergies: Symptoms, Diagnosis, and Treatment Past Issues / Summer 2011 ... of Contents Is It a Cold or an Allergy? Symptoms Cold Airborne Allergy Cough Common Sometimes General ...

  7. Projections of Seasonal Patterns in Temperature- Related Deaths for Manhattan, New York

    Science.gov (United States)

    Li, Tiantian; Horton, Radley M.; Kinney, Patrick L.

    2013-01-01

    Global average temperatures have been rising for the past half-century, and the warming trend has accelerated in recent decades. Further warming is expected over the next few decades, with significant regional variations. These warming trends will probably result in more frequent, intense and persistent periods of hot temperatures in summer, and generally higher temperatures in winter. Daily death counts in cities increase markedly when temperatures reach levels that are very high relative to what is normal in a given location. Relatively cold temperatures also seem to carry risk. Rising temperatures may result in more heat-related mortality but may also reduce cold-related mortality, and the net impact on annual mortality remains uncertain. Here we use 16 downscaled global climate models and two emissions scenarios to estimate present and future seasonal patterns in temperature-related mortality in Manhattan, New York. All 32 projections yielded warm-season increases and cold-season decreases in temperature-related mortality, with positive net annual temperature-related deaths in all cases. Monthly analyses showed that the largest percentage increases may occur in May and September. These results suggest that, over a range of models and scenarios of future greenhouse gas emissions, increases in heat-related mortality could outweigh reductions in cold-related mortality, with shifting seasonal patterns.

  8. Disruption of the European climate seasonal clock in a warming world

    Science.gov (United States)

    Cattiaux, J.; Cassou, C.

    2015-12-01

    Strength and inland penetration of the oceanic westerly flow over Europe control a large part of the temperature variability over most of the continent. Reduced westerlies, linked to high-pressure anomalies over Scandinavia, induce cold conditions in winter and warm conditions in summer. Here we propose to define the onset of these two seasons as the calendar day where the daily circulation/temperature relationship over Western Europe switches sign. According to this meteorologically-based metrics assessed from several observational datasets, we provide robust evidence for an earlier summer onset by ~10 days between the 1960s and 2000s. Results from model ensemble simulations dedicated to detection-attribution show that this calendar advance is incompatible with the sole internal climate variability and can be attributed to anthropogenic forcings. Late winter snow disappearance over Eastern Europe affects cold air intrusion to the West when easterlies blow, and is mainly responsible for the observed present-day and near-future summer advance. Our findings agree with phenological-based trends (earlier spring events) reported for many living species over Europe, for which they provide a novel dynamical interpretation beyond the traditionally evoked global warming effect. Based on business-as-usual scenario, a seasonal shift of ~25 days is expected by 2100 for summer onset, while no clear signal arises for winter onset.

  9. Using bacterial and necrophagous insect dynamics for post-mortem interval estimation during cold season: Novel case study in Romania.

    Science.gov (United States)

    Iancu, Lavinia; Carter, David O; Junkins, Emily N; Purcarea, Cristina

    2015-09-01

    Considering the biogeographical characteristics of forensic entomology, and the recent development of forensic microbiology as a complementary approach for post-mortem interval estimation, the current study focused on characterizing the succession of necrophagous insect species and bacterial communities inhabiting the rectum and mouth cavities of swine (Sus scrofa domesticus) carcasses during a cold season outdoor experiment in an urban natural environment of Bucharest, Romania. We monitored the decomposition process of three swine carcasses during a 7 month period (November 2012-May 2013) corresponding to winter and spring periods of a temperate climate region. The carcasses, protected by wire cages, were placed on the ground in a park type environment, while the meteorological parameters were constantly recorded. The succession of necrophagous Diptera and Coleoptera taxa was monitored weekly, both the adult and larval stages, and the species were identified both by morphological and genetic characterization. The structure of bacterial communities from swine rectum and mouth tissues was characterized during the same time intervals by denaturing gradient gel electrophoresis (DGGE) and sequencing of 16S rRNA gene fragments. We observed a shift in the structure of both insect and bacterial communities, primarily due to seasonal effects and the depletion of the carcass. A total of 14 Diptera and 6 Coleoptera species were recorded on the swine carcasses, from which Calliphora vomitoria and C. vicina (Diptera: Calliphoridae), Necrobia violacea (Coleoptera: Cleridae) and Thanatophilus rugosus (Coleoptera: Silphidae) were observed as predominant species. The first colonizing wave, primarily Calliphoridae, was observed after 15 weeks when the temperature increased to 13°C. This was followed by Muscidae, Fanniidae, Anthomyiidae, Sepsidae and Piophilidae. Families belonging to Coleoptera Order were observed at week 18 when temperatures raised above 18°C, starting with

  10. A Synoptic Climatology of Combined Severe/Weather/Flash Flood Events

    Science.gov (United States)

    Pallozzi, Kyle J.

    Classical forms of severe weather such as tornadoes, damaging convective wind gusts, and large hail, as well as flash flooding events, all have potentially large societal impacts. This impact is further magnified when these hazards occur simultaneously in time and space. A major challenge for operational forecasters is how to accurately predict the occurrence of combined storm hazards, and how to communicate the associated multiple threat hazards to the public. A seven-year climatology (2009-2015) of combined severe weather/flash flooding (SVR/FF) events across the contiguous United States was developed in attempt to study the combined SVR/FF event hazards further. A total of 211 total cases were identified and sub-divided into seven subcategories based on their convective morphology and meteorological characteristics. Heatmaps of event report frequency were created to extract spatial, seasonal and interannual patterns in SVR/FF event activity. Diurnal trends were examined from time series plots of tornado, hail, wind and flash flood/flood reports. Event-centered composites of environmental variables were created for each subcategory from 13 km RUC/RAP analyses. Representative cases studies were conducted for each subcategory. A "ring of fire" with the highest levels of SVR/FF event activity was noted across the central United States. SVR/FF events were least common in the Southeast, High Plains, and Northern Plains. Enhanced SVR/FF activity reflected contributions from synoptic events during the cool and shoulder seasons over the Lower Mississippi, Arkansas and Tennessee Valleys, and MCS activity during the warm season over the lower Great Plains, and the Upper Mississippi, Missouri and Ohio River Valleys. Results from the composite analyses indicated that relatively high values of CAPE, surface-500 hPa shear and precipitable water were observed for all subcategories. Case studies show that many high-end SVR/FF events featured slow-moving, or quasi

  11. 寒害与季节变化对油棕叶片大中量营养元素含量及其变化规律的影响%Effect of Cold Injuries and Seasonal Variations on Nutritional Element of Oil Palm Leaves

    Institute of Scientific and Technical Information of China (English)

    刘立云; 李艳; 雷新涛; 曹红星; 张如莲

    2013-01-01

    In this paper,the effects of cold injuries and seasonal variations on the nutritional elements of oil palm leaves were studied.The results showed that the content of nitrogen in oil palm leaf decreased during the cold injury and increased slowly afterwards; the content of phosphorus decreased obviously under cold injury and presented ‘W' curves during seasonal variations; the content of potassium declined during seasonal variations,however,the content of calcium significantly increased and presented ‘M' curv es under cold injury.The content of sodium of oil palm leaves decreased in seasonal variation but increased during the cold injuries.It indicated that the nutritional elements of oil palm were fluctuated with seasonal variations,which would provide some fertilizer guides and cold tolerance theories for oil palm.%本文探索了寒害对油棕叶片大中量营养元素含量及其变化规律的影响.结果表明:油棕叶片N含量在寒害期间整体呈现降低趋势,而后缓慢升高;P含量在寒害期间明显下降,在整个周年的季节变化中呈现规则的“W”变化曲线;K含量在周年变化中,呈现下降趋势;Ca含量在寒害期间呈明显增高的趋势,呈现规则的“M”变化曲线;油棕叶片Na含量在周年季节变化中,呈现出明显的下降趋势,寒害期间油棕叶片Na元素含量仍呈增高的趋势.这表明油棕叶片营养元素含量在生长季节的波动情况,因季节不同而异.此结果将为油棕施肥和耐寒性提供理论指导.

  12. Differential response of vegetation in Hulun Lake region at the northern margin of Asian summer monsoon to extreme cold events of the last deglaciation

    Science.gov (United States)

    Zhang, Shengrui; Xiao, Jule; Xu, Qinghai; Wen, Ruilin; Fan, Jiawei; Huang, Yun; Yamagata, Hideki

    2018-06-01

    The response of vegetation to extreme cold events during the last deglaciation is important for assessing the impact of possible extreme climatic events on terrestrial ecosystems under future global warming scenarios. Here, we present a detailed record of the development of regional vegetation in the northern margin of Asian summer monsoon during the last deglaciation (16,500-11,000 cal yr BP) based on a radiocarbon-dated high-resolution pollen record from Hulun Lake, northeast China. The results show that the regional vegetation changed from subalpine meadow-desert steppe to mixed coniferous and deciduous forest-typical steppe during the last deglaciation. However, its responses to the Heinrich event 1 (H1) and the Younger Dryas event (YD) were significantly different: during the H1 event, scattered sparse forest was present in the surrounding mountains, while within the lake catchment the vegetation cover was poor and was dominated by desert steppe. In contrast, during the YD event, deciduous forest developed and the proportion of coniferous forest increased in the mountains, the lake catchment was occupied by typical steppe. We suggest that changes in Northern Hemisphere summer insolation and land surface conditions (ice sheets and sea level) caused temperature and monsoonal precipitation variations that contributed to the contrasting vegetation response during the two cold events. We conclude that under future global warming scenarios, extreme climatic events may cause a deterioration of the ecological environment of the Hulun Lake region, resulting in increased coniferous forest and decreased total forest cover in the surrounding mountains, and a reduction in typical steppe in the lake catchment.

  13. Temporal relationships between colds, upper respiratory viruses detected by polymerase chain reaction, and otitis media in young children followed through a typical cold season.

    Science.gov (United States)

    Winther, Birgit; Alper, Cuneyt M; Mandel, Ellen M; Doyle, William J; Hendley, J Owen

    2007-06-01

    Otitis media is a frequent complication of a viral upper respiratory tract infection, and the reported co-incidence of those diseases increases with assay sensitivity and sampling density. We determined the incidence of otitis-media complications in young children when referenced to cold-like illnesses and to concurrent virus recovery from the nasopharynx. A total of 60 children from 24 families were followed from October 2003 through April 30, 2004, by daily parental recording of illness signs, weekly pneumatic otoscopic examinations, and periodic polymerase chain reaction assay of collected nasal fluids for common viruses. One hundred ninety-nine cold-like illnesses were observed, but a sample for virus assay was not collected concurrent with 71 episodes. Of the remainder, 73% of cold-like illnesses were temporally related to recovery of 1 or a combination of the assayed viruses, with rhinovirus predominating. For non-cold-like illness periods, 54 (18%) of 297 assays were positive for virus, and the virus frequency distribution was similar to that for cold-like illnesses. There were 93 diagnosed otitis-media episodes; 65 (70%) of these occurred during a cold-like illness. For the 79 otitis-media episodes with available nasal samples, 61 (77%) were associated with a positive virus result. In this population, the otitis-media complication rate for a cold-like illness was 33%. A cold-like illness was not a prerequisite for polymerase chain reaction detection of viruses in the nose and nasopharynx of young children. Viral detection by polymerase chain reaction in the absence of a cold-like illness is associated with complications in some subjects. Otitis media is a complication of viral infection both with and without concurrent cold-like illnesses, thus downwardly biasing coincidence estimates that use cold-based illnesses as the denominator.

  14. Signal modulation in cold-dark-matter detection

    International Nuclear Information System (INIS)

    Freese, K.; Frieman, J.; Gould, A.

    1988-01-01

    If weakly interacting massive particles (WIMP's) are the dark matter in the galactic halo, they may be detected in low-background ionization detectors now operating or with low-temperature devices under development. In detecting WIMP's of low mass or WIMP's with spin-dependent nuclear interactions (e.g., photinos), a principal technical difficulty appears to be achieving very low thresholds (approx. < keV) in large (∼ kg) detectors with low background noise. We present an analytic treatment of WIMP detection and show that the seasonal modulation of the signal can be used to detect WIMP's even at low-signal-to-background levels and thus without the necessity of going to very-low-energy thresholds. As a result, the prospects for detecting a variety of cold-dark-matter candidates may be closer at hand than previously thought. We discuss in detail the detector characteristics required for a number of WIMP candidates, and carefully work out expected event rates for several present and proposed detectors

  15. Orbital forcing of the late Pleistocene boreal summer monsoon: Links to North Atlantic cold events and El Nino; Southern Oscillation. Geologica Ultraiectina (313)

    NARCIS (Netherlands)

    Ziegler, M.

    2009-01-01

    This thesis revolves about the timing of precession-related variations in the boreal summer monsoon and the impact of North Atlantic cold events and the El Nino Southern Oscillation on this timing. Transient climate modelling experiments indicate that the intensity of the Northern Hemisphere summer

  16. NEW SEASON NEW HOPES: OFF-SEASON OPTIMISM

    Directory of Open Access Journals (Sweden)

    Oguz Ersan

    2017-12-01

    Full Text Available While literature on the relation between on-field sports performance and stock returns is ample, there is very limited evidence on off-season stage. Constituting around 3 months, off-seasons do not only occupy a significant part of the year but also represent totally different characteristics than on-seasons. They lack the periodic, unambiguous news events in on-seasons (match results, instead they are associated with highly uncertain transfer news and rumors. We show that this distinction has several impacts on the stock market performances of soccer clubs. Most notably, off-seasons generate substantially higher (excess returns. After controlling for other variables, the estimated effect of off-season periods is as high as 38.75%, annually. In line with several seminal studies, we link this fact to increased optimism and betting behavior through uncertain periods; and periods prior to the start of a new calendar (in our case, new season. For all of the examined 7 clubs (3 from Italy and 4 from Turkey, mean excess returns over the market are positive (negative in off-seasons (on-seasons. On-seasons are associated with increased trading activity due to more frequent news. Stocks of Italian clubs are evidently more volatile through off-seasons while volatility results for the stocks of Turkish clubs are not consistent.

  17. Seasonal and diel effects on acoustic fish biomass estimates: application to a shallow reservoir with untargeted common carp (Cyprinus carpio)

    Science.gov (United States)

    Djemali, Imed; Yule, Daniel; Guillard, Jean

    2016-01-01

    The aim of the present study was to understand how seasonal fish distributions affect acoustically derived fish biomass estimates in a shallow reservoir in a semi-arid country (Tunisia). To that end, sampling events were performed during four seasons (spring (June), summer (September), autumn (December) and winter (March)) that included day and night surveys. A Simrad EK60 echosounder, equipped with two 120-kHz split-beam transducers for simultaneous horizontal and vertical beaming, was used to sample the entire water column. Surveys during spring and summer and daytime hours of winter were deemed unusable owing to high methane flux from the sediment, and during the day survey of autumn, fish were close to the reservoir bottom leading to low detectability. It follows that acoustic surveys should be conducted only at night during the cold season (December–March) for shallow reservoirs having carp Cyprinus carpio (L.) as the dominant species. Further, night-time biomass estimates during the cold season declined significantly (P < 0.001) from autumn to winter. Based on our autumn night-time survey, overall fish biomass in the Bir-Mcherga Reservoir was high (mean (± s.d.) 185 ± 98 tonnes (Mg)), but annual fishery exploitation is low (19.3–24.1 Mg) because the fish biomass is likely dominated by invasive carp not targeted by fishers. The results suggest that controlling carp would help improve the fishery.

  18. Establishing native warm season grasses on Eastern Kentucky strip mines

    Energy Technology Data Exchange (ETDEWEB)

    Barnes, T.G.; Larkin, J.L.; Arnett, M.B. [Univ. of Kentucky, Lexington, KY (United States). Dept. of Forestry

    1998-12-31

    The authors evaluated various methods of establishing native warm season grasses on two reclaimed Eastern Kentucky mines from 1994--1997. Most current reclamation practices incorporate the use of tall fescue (Festuca arundinacea) and other cool-season grasses/legumes that provide little wildlife habitats. The use of native warm season grasses will likely improve wildlife habitat on reclaimed strip mines. Objectives of this study were to compare the feasibility of establishing these grasses during fall, winter, or spring using a native rangeland seeder or hydroseeding; a fertilizer application at planting; or cold-moist stratification prior to hydroseeding. Vegetative cover, bare ground, species richness, and biomass samples were collected at the end of each growing season. Native warm season grass plantings had higher plant species richness compared to cool-season reclamation mixtures. There was no difference in establishment of native warm season grasses as a result of fertilization or seeding technique. Winter native warm season grass plantings were failures and cold-moist stratification did not increase plant establishment during any season. As a result of a drought during 1997, both cool-season and warm season plantings were failures. Cool-season reclamation mixtures had significantly more vegetative cover and biomass compared to native warm season grass mixtures and the native warm season grass plantings did not meet vegetative cover requirements for bond release. Forbs and legumes that established well included pale purple coneflower (Echinacea pallida), lance-leaf coreopsis (Coreopsis lanceolata), round-headed lespedeza (Lespedeza capitata), partridge pea (Cassia fasiculata), black-eyed susan (Rudbeckia hirta), butterfly milkweed (Asclepias tuberosa), and bergamot (Monarda fistulosa). Results from two demonstration plots next to research plots indicate it is possible to establish native warm season grasses on Eastern Kentucky strip mines for wildlife habitat.

  19. Establishing native warm season grasses on Eastern Kentucky strip mines

    International Nuclear Information System (INIS)

    Barnes, T.G.; Larkin, J.L.; Arnett, M.B.

    1998-01-01

    The authors evaluated various methods of establishing native warm season grasses on two reclaimed Eastern Kentucky mines from 1994--1997. Most current reclamation practices incorporate the use of tall fescue (Festuca arundinacea) and other cool-season grasses/legumes that provide little wildlife habitats. The use of native warm season grasses will likely improve wildlife habitat on reclaimed strip mines. Objectives of this study were to compare the feasibility of establishing these grasses during fall, winter, or spring using a native rangeland seeder or hydroseeding; a fertilizer application at planting; or cold-moist stratification prior to hydroseeding. Vegetative cover, bare ground, species richness, and biomass samples were collected at the end of each growing season. Native warm season grass plantings had higher plant species richness compared to cool-season reclamation mixtures. There was no difference in establishment of native warm season grasses as a result of fertilization or seeding technique. Winter native warm season grass plantings were failures and cold-moist stratification did not increase plant establishment during any season. As a result of a drought during 1997, both cool-season and warm season plantings were failures. Cool-season reclamation mixtures had significantly more vegetative cover and biomass compared to native warm season grass mixtures and the native warm season grass plantings did not meet vegetative cover requirements for bond release. Forbs and legumes that established well included pale purple coneflower (Echinacea pallida), lance-leaf coreopsis (Coreopsis lanceolata), round-headed lespedeza (Lespedeza capitata), partridge pea (Cassia fasiculata), black-eyed susan (Rudbeckia hirta), butterfly milkweed (Asclepias tuberosa), and bergamot (Monarda fistulosa). Results from two demonstration plots next to research plots indicate it is possible to establish native warm season grasses on Eastern Kentucky strip mines for wildlife habitat

  20. Main processes of the Atlantic cold tongue interannual variability

    Science.gov (United States)

    Planton, Yann; Voldoire, Aurore; Giordani, Hervé; Caniaux, Guy

    2018-03-01

    The interannual variability of the Atlantic cold tongue (ACT) is studied by means of a mixed-layer heat budget analysis. A method to classify extreme cold and warm ACT events is proposed and applied to ten various analysis and reanalysis products. This classification allows 5 cold and 5 warm ACT events to be selected over the period 1982-2007. Cold (warm) ACT events are defined by the presence of negative (positive) sea surface temperature (SST) anomalies at the center of the equatorial Atlantic in late boreal spring, preceded by negative (positive) zonal wind stress anomalies in the western equatorial Atlantic. An ocean general circulation model capable of reconstructing the interannual variability of the ACT correctly is used to demonstrate that cold ACT events develop rapidly from May to June mainly due to intense cooling by vertical mixing and horizontal advection. The simulated cooling at the center of the basin is the result of the combined effects of non-local and local processes. The non-local process is an upwelling associated with an eastward-propagating Kelvin wave, which makes the mixed-layer more shallow and preconditions the upper layers to be cooled by an intense heat loss at the base of the mixed-layer, which is amplified by a stronger local injection of energy from the atmosphere. The early cooling by vertical mixing in March is also shown to be a good predictor of June cooling. In July, horizontal advection starts to warm the mixed-layer abnormally and damps SST anomalies. The advection anomalies, which result from changes in the horizontal temperature gradient, are associated in some cases with the propagation of Rossby waves along the equator. During warm ACT events, processes are reversed, generating positive SST anomalies: a downwelling Kelvin wave triggers stratification anomalies and mixed-layer depth anomalies, amplified by a weaker injection of energy from the atmosphere in May-June. In July, warm ACT events are abnormally cooled due to

  1. Prediction uncertainty in seasonal partial duration series

    DEFF Research Database (Denmark)

    Rasmussen, Peter Funder; Rosbjerg, Dan

    1991-01-01

    In order to obtain a good description of the exceedances in a partial duration series it is often necessary to divide the year into a number (2-4) of seasons. Hereby a stationary exceedance distribution can be maintained within each season. This type of seasonal models may, however, not be suitable...... for prediction purposes due to the large number of parameters required. In the particular case with exponentially distributed exceedances and Poissonian occurrence times the precision of the T year event estimator has been thoroughly examined considering both seasonal and nonseasonal models. The two......-seasonal probability density function of the T year event estimator has been deduced and used in the assessment of the precision of approximate moments. The nonseasonal approach covered both a total omission of seasonality by pooling data from different flood seasons and a discarding of nonsignificant season(s) before...

  2. MECHANISMS FOR THE SEASONAL CYCLE IN THE ANTARCTIC COASTAL OCEANS

    OpenAIRE

    オオシマ; Kay I., OHSHIMA

    1996-01-01

    Seasonal variations of the Antarctic coastal oceans has not been well understood owing to logistical difficulties in observations, especially during the ice-covered season. Recently, 'Weddell Gyre Study' and 'Japanese Antarctic Climate Research program' have revealed the following seasonal variations in the Antarctic coastal ocean. First, the thickness of the Winter Water (WW) layer, characterized by cold, fresh, oxygen-rich water, exhibits its maximum in the austral fall and its minimum in t...

  3. Effects of germination season on life history traits and on transgenerational plasticity in seed dormancy in a cold desert annual.

    Science.gov (United States)

    Lu, Juan J; Tan, Dun Y; Baskin, Carol C; Baskin, Jerry M

    2016-04-27

    The maternal environment can influence the intensity of seed dormancy and thus seasonal germination timing and post-germination life history traits. We tested the hypotheses that germination season influences phenotypic expression of post-germination life history traits in the cold desert annual Isatis violascens and that plants from autumn- and spring-germinating seeds produce different proportions of seeds with nondeep and intermediate physiological dormancy (PD). Seeds were sown in summer and flexibility in various life history traits determined for plants that germinated in autumn and in spring. A higher percentage of spring- than of autumn-germinating plants survived the seedling stage, and all surviving plants reproduced. Number of silicles increased with plant size (autumn- > spring-germinating plants), whereas percent dry mass allocated to reproduction was higher in spring- than in autumn-germinating plants. Autumn-germinating plants produced proportionally more seeds with intermediate PD than spring-germinating plants, while spring-germinating plants produced proportionally more seeds with nondeep PD than autumn-germinating plants. Flexibility throughout the life history and transgenerational plasticity in seed dormancy are adaptations of I. violascens to its desert habitat. Our study is the first to demonstrate that autumn- and spring-germinating plants in a species population differ in proportion of seeds produced with different levels of PD.

  4. Prevalence of hypertension and hypertension control rates among elderly adults during the cold season in rural Northeast China: a cross-sectional study.

    Science.gov (United States)

    Kawazoe, Nobuo; Zhang, Xiumin; Chiang, Chifa; Liu, Hongjian; Li, Jinghua; Hirakawa, Yoshihisa; Aoyama, Atsuko

    2018-05-01

    Objective: The burden of noncommunicable diseases (NCDs) is increasing in China, together with economic development and social changes. The prevalence of risk factors for NCDs, such as overweight/obesity, hypertension, diabetes, and dyslipidemia, is reported to be high even among poor residents of rural areas. We aimed to investigate the prevalence of hypertension among elderly adults in rural Northeast China and the proportion with controlled hypertension among those on antihypertensive medication (hypertension control rate). We also aimed to examine the association of hypertension control with health facilities that provide treatment. Methods: We conducted a community-based cross-sectional study in six rural villages of Northeast China from February to early March, 2012. We interviewed 1593 adults aged 50-69 years and measured their blood pressure. We examined the differences in mean blood pressure between participants who obtained antihypertensive medication from village clinics and those who obtained medication from other sources, using analysis of covariance adjusted for several covariates. Results: The prevalence of hypertension among participants was as high as 63.3%, but the hypertension control rate was only 8.4%. Most villagers (98.1%) were not registered in the chronic disease treatment scheme of the public rural health insurance. The mean systolic blood pressure, adjusted for the covariates, of participants who obtained antihypertensive medication from village clinics was significantly lower than that of participants who obtained medication from township hospitals (by 16.5 mmHg) or from private pharmacies (by 7.3 mmHg). Conclusion: The prevalence of hypertension was high and the hypertension control rate low among elderly villagers during the cold season. As treatment at village clinics, which villagers can access during the cold season seems to be more effective than self-medication or treatment at distant hospitals, improving the quality of treatment

  5. The role of Xylella fastidiosa cold shock proteins in Pierce’s disease of grapes

    Science.gov (United States)

    Pierce’s disease of grapevine, caused by the bacterial pathogen Xylella fastidiosa (Xf) is limited to warmer climates, and plant infection can be eliminated by cold winter conditions. Milder winters can increase the likelihood of pathogen persistence from one growing season to the next. Cold adaptat...

  6. Atmospheric forcing of cool subsurface water events in Bahía Culebra, Gulf of Papagayo, Costa Rica

    Directory of Open Access Journals (Sweden)

    Eric J. Alfaro

    2012-04-01

    Full Text Available Bahía Culebra, at Gulf of Papagayo on the north Pacific coast of Costa Rica, is an area of seasonal upwelling where more intense cooling events may occur during some boreal winter weeks mainly. To study these extreme cool events, records of nine sea subsurface temperature stations from 1998 to 2010 were analyzed. Five events associated with extremely cool temperatures in this region were identified from these records and taken as study cases. Sea temperatures decreased about 8-9ºC during these events and occurred while cold fronts were present in the Caribbean, with strong trade wind conditions over Central America. These strong wind conditions may have favored the offshore displacement of the sea surface water. The axis of Bahía Culebra runs northeastsouthwest, a condition that favors and triggers cool water events, mainly because the displaced water is replaced by water from deeper levels.

  7. Burden and seasonality of testicular torsion in tropical Africa: Analysis of incident cases in a Nigerian community

    Directory of Open Access Journals (Sweden)

    Jibril O. Bello

    2018-03-01

    Full Text Available Introduction: Children, adolescents and young adults in tropical Africa occasionally presents to the emergency department with testicular torsion. However, no estimates of the burden of the condition is available and there is also sparse evidence of a seasonal variation in incidence. Objective: To determine the incidence and seasonality of the condition in a Nigerian community. Subjects and methods: A retrospective review of incident cases of testicular torsion occurring in a typical tropical sub-Saharan African community between January 2011 and December 2016 was performed. Incidence rates were calculated and trend analysis performed to evaluate for seasonality. Results: Twenty-three patients were seen during the study period and the average annual incidence of testicular torsion among ‘at risk’ males (<40 years was 2.7/100,000. Testicular salvage rate was 81%. Cases occurred 91% higher than average during the cold season (November to January. Trend analysis revealed a significant seasonal difference in the number of cases seen (p = 0.045 and Post Hoc tests (Tukey further showed that this is attributable to the seasonal difference between the cold season and the warmer early rains period (p = 0.036. Conclusion: The burden of testicular torsion found in the studied tropical sub-Saharan community is comparable to other regions of the world and seasonal variation in incidence does occur with a significant increase in cases during the cold season. Keywords: Testicular torsion, Seasonality, Disease burden, Orchiopexy, Orchiectomy

  8. Effects of recent warm and cold spells on European plant phenology

    Science.gov (United States)

    Menzel, A.; Estrella, N.; Seifert, H.

    2009-04-01

    Numerous studies have concurrently documented a progressively earlier start for vegetation activity in spring and a lengthening of the growing season during the last 2 to 5 decades in the temperate northern hemisphere. In contrast to climatic factors influencing autumn phenology, the climate signal controlling spring and summer phenology is fairly well understood: nearly all phenophases correlate with temperatures in the preceding 1 to 3 months. The changes currently experienced by emergence of vegetation may reach 6 to 8 d per °C. But how will this well-known, often linearly described relationship change in case of more frequent and more stronger temperature extremes? We thus studied the temperature response of European phenological records to cold and warm spells using the COST725 data base (www.cost725.org). We restricted our analysis to the time period 1951-2006 due to the relatively better coverage of Europe by phenological records. Up to now, 20 European countries contributed more than 7 Mio. phenological observations to this data base including 64 species and 22 different phases. The phenological observations compiled originated from different sources and phenological networks. Unfortunately there is no entire coverage and the data are very lumped. Cold and warm spells were identified using daily mean temperature data (1951-2006) on a 0.5° grid for Europe provided by the EU-FP6 project ENSEMBLES (http://www.ensembles-eu.org, http://eca.knmi.nl). The study area covered Europe and was limited to 40°E. For the whole study period, mean monthly and seasonal mean temperatures well as the corresponding standard deviations were calculated for each grid point. The annual monthly or seasonal temperature at a grid point was defined as cold (very cold, warm, very warm) by its deviation from the long-term average (more than 1.5 or 3sd, respectively). Warm and cold spells were selected when either the percentages of crossing 1.5sd were greater than 50% for the total

  9. Dynamical prediction of flu seasonality driven by ambient temperature: influenza vs. common cold

    Science.gov (United States)

    Postnikov, Eugene B.

    2016-01-01

    This work presents a comparative analysis of Influenzanet data for influenza itself and common cold in the Netherlands during the last 5 years, from the point of view of modelling by linearised SIRS equations parametrically driven by the ambient temperature. It is argued that this approach allows for the forecast of common cold, but not of influenza in a strict sense. The difference in their kinetic models is discussed with reference to the clinical background.

  10. Intraspecies differences in cold hardiness, carbohydrate content and β-amylase gene expression of Vaccinium corymbosum during cold acclimation and deacclimation.

    Science.gov (United States)

    Lee, Jun Hyung; Yu, Duk Jun; Kim, Su Jin; Choi, Doil; Lee, Hee Jae

    2012-12-01

    Changes in cold hardiness, carbohydrate content and β-amylase gene expression were monitored in the shoots of the highbush blueberry (Vaccinium corymbosum L.) cultivars 'Sharpblue' and 'Jersey' during cold acclimation (CA) and deacclimation (DA). The seasonal patterns were similar in both cultivars, but the levels of cold hardiness determined by electrolyte leakage analysis were significantly different; 'Jersey' was hardier than 'Sharpblue'. Cold hardiness was closely related to total soluble sugar content (r = -0.98** and -0.99** for 'Sharpblue' and 'Jersey', respectively). In 'Jersey', more soluble sugars accumulated during CA. Of the detected soluble sugars, glucose, fructose and raffinose contents were significantly associated with cold hardiness in both cultivars. Sucrose was abundant in both cultivars, and stachyose content changed significantly during CA and DA. However, they were not associated with cold hardiness. A sharp decrease in starch contents in the middle of CA coincided with β-amylase gene (VcBMY) expression, indicating the conversion of starch into soluble sugars. During CA, VcBMY was expressed up to twofold higher in 'Jersey' than in 'Sharpblue'. These results suggest that intraspecies differences in the cold hardiness of highbush blueberries are associated with total soluble sugar content, which is driven partly by differential expression of VcBMY.

  11. Effects of air pollution and seasons on health-related quality of life of Mongolian adults living in Ulaanbaatar: cross-sectional studies

    Directory of Open Access Journals (Sweden)

    Motoyuki Nakao

    2017-06-01

    Full Text Available Abstract Background Ulaanbaatar, Mongolia, is known as severely air-polluted city in the world due to increased coal consumption in the cold season. The health effects of air pollution in Mongolia such as mortality, morbidity and symptoms have been previously reported. However, the concept of health-related quality of life (HR-QoL, which refers to the individual’s perception of well-being, should also be included as an adverse health outcome of air pollution. Methods Surveys on the Mongolian people living in Ulaanbaatar were performed in the warm and cold seasons. Self-completed questionnaires on the subjects’ HR-QoL, data from health checkups and pulmonary function tests by respiratory specialists were collected for Mongolian adults aged 40–79 years (n = 666. Ambient PM2.5 and PM10 were concurrently sampled and the components were analyzed to estimate the source of air pollution. Results In logistic regression analyses, respiratory symptoms and smoke-rich fuels were associated with reduced HR-QoL (> 50th percentile vs. ≤ 50th percentile. PM 2.5 levels were much higher in the cold season (median 86.4 μg/m3 (IQR: 58.7–121.0 than in the warm season (12.2 μg/m3 (8.9–21.2. The receptor model revealed that the high PM2.5 concentration in the cold season could be attributed to solid fuel combustion. The difference in HR-QoL between subjects with and without ventilatory impairment was assessed after the stratification of the subjects by season and household fuel type. There were no significant differences in HR-QoL between subjects with and without ventilatory impairment regardless of household fuel type in the warm season. In contrast, subjects with ventilatory impairment who used smoke-rich fuel in the cold season had a significantly lower HR-QoL. Conclusions Our study showed that air pollution in Ulaanbaatar worsened in the cold season and was estimated to be contributed by solid fuel combustion. Various aspects of HR-QoL in

  12. Effects of air pollution and seasons on health-related quality of life of Mongolian adults living in Ulaanbaatar: cross-sectional studies.

    Science.gov (United States)

    Nakao, Motoyuki; Yamauchi, Keiko; Ishihara, Yoko; Omori, Hisamitsu; Ichinnorov, Dashtseren; Solongo, Bandi

    2017-06-23

    Ulaanbaatar, Mongolia, is known as severely air-polluted city in the world due to increased coal consumption in the cold season. The health effects of air pollution in Mongolia such as mortality, morbidity and symptoms have been previously reported. However, the concept of health-related quality of life (HR-QoL), which refers to the individual's perception of well-being, should also be included as an adverse health outcome of air pollution. Surveys on the Mongolian people living in Ulaanbaatar were performed in the warm and cold seasons. Self-completed questionnaires on the subjects' HR-QoL, data from health checkups and pulmonary function tests by respiratory specialists were collected for Mongolian adults aged 40-79 years (n = 666). Ambient PM2.5 and PM10 were concurrently sampled and the components were analyzed to estimate the source of air pollution. In logistic regression analyses, respiratory symptoms and smoke-rich fuels were associated with reduced HR-QoL (> 50th percentile vs. ≤ 50th percentile). PM 2.5 levels were much higher in the cold season (median 86.4 μg/m 3 (IQR: 58.7-121.0)) than in the warm season (12.2 μg/m 3 (8.9-21.2). The receptor model revealed that the high PM2.5 concentration in the cold season could be attributed to solid fuel combustion. The difference in HR-QoL between subjects with and without ventilatory impairment was assessed after the stratification of the subjects by season and household fuel type. There were no significant differences in HR-QoL between subjects with and without ventilatory impairment regardless of household fuel type in the warm season. In contrast, subjects with ventilatory impairment who used smoke-rich fuel in the cold season had a significantly lower HR-QoL. Our study showed that air pollution in Ulaanbaatar worsened in the cold season and was estimated to be contributed by solid fuel combustion. Various aspects of HR-QoL in subjects with ventilatory impairment using smoke-rich fuels deteriorated

  13. Seasonal changes in daily metabolic patterns of tegu lizards (Tupinambis merianae) placed in the cold (17 degrees C) and dark.

    Science.gov (United States)

    Milsom, William K; Andrade, Denis V; Brito, Simone P; Toledo, Luis F; Wang, Tobias; Abe, Augusto S

    2008-01-01

    Abstract Oxygen consumption rate was measured continuously in young tegu lizards Tupinambis merianae exposed to 4 d at 25 degrees C followed by 7-10 d at 17 degrees C in constant dark at five different times of the year. Under these conditions, circadian rhythms in the rate of oxygen consumption persisted for anywhere from 1 d to the entire 2 wk in different individuals in all seasons except the winter. We also saw a progressive decline in standard oxygen consumption rate (at highly variable rates in different individuals) to a very low rate that was seasonally independent (ranging from 19.1 +/- 6.2 to 27.7 +/- 0.2 mL kg(-1) h(-1) across seasons). Although this degree of reduction appeared to take longer to invoke when starting from higher metabolic rates, tegu lizards reduced their metabolism to the low rates seen in winter dormancy at all times of the year when given sufficient time in the cold and dark. In the spring and summer, tegus reduced their standard metabolic rate (SMR) by 80%-90% over the experimental run, but only roughly 20%-30% of the total fall was due to the reduction in temperature; 70%-80% of the total fall occurred at constant temperature. By autumn, when the starting SMR on the first night at 25 degrees C was already reduced by 59%-81% (early and late autumn, respectively) from peak summer values, virtually all of the fall (63%-83%) in metabolism was due to the reduction in temperature. This suggests that the temperature-independent reduction of metabolism was already in place by autumn before the tegus had entered winter dormancy.

  14. Biological Characterization of Microenvironments in a Hypersaline Cold Spring Mars Analog

    Directory of Open Access Journals (Sweden)

    Haley M. Sapers

    2017-12-01

    Full Text Available While many habitable niches on Earth are characterized by permanently cold conditions, little is known about the spatial structure of seasonal communities and the importance of substrate-cell associations in terrestrial cyroenvironments. Here we use the 16S rRNA gene as a marker for genetic diversity to compare two visually distinct but spatially integrated surface microbial mats on Axel Heiberg Island, Canadian high arctic, proximal to a perennial saline spring. This is the first study to describe the bacterial diversity in microbial mats on Axel Heiberg Island. The hypersaline springs on Axel Heiberg represent a unique analog to putative subsurface aquifers on Mars. The Martian subsurface represents the longest-lived potentially habitable environment on Mars and a better understanding of the microbial communities on Earth that thrive in analog conditions will help direct future life detection missions. The microbial mats sampled on Axel Heiberg are only visible during the summer months in seasonal flood plains formed by melt water and run-off from the proximal spring. Targeted-amplicon sequencing revealed that not only does the bacterial composition of the two mat communities differ substantially from the sediment community of the proximal cold spring, but that the mat communities are distinct from any other microbial community in proximity to the Arctic springs studied to date. All samples are dominated by Gammaproteobacteria: Thiotichales is dominant within the spring samples while Alteromonadales comprises a significant component of the mat communities. The two mat samples differ in their Thiotichales:Alteromonadales ratio and contribution of Bacteroidetes to overall diversity. The red mats have a greater proportion of Alteromonadales and Bacteroidetes reads. The distinct bacterial composition of the mat bacterial communities suggests that the spring communities are not sourced from the surface, and that seasonal melt events create

  15. Functional characterization of the Hyles euphorbiae hawkmoth transcriptome reveals strong expression of phorbol ester detoxification and seasonal cold hardiness genes.

    Science.gov (United States)

    Barth, M Benjamin; Buchwalder, Katja; Kawahara, Akito Y; Zhou, Xin; Liu, Shanlin; Krezdorn, Nicolas; Rotter, Björn; Horres, Ralf; Hundsdoerfer, Anna K

    2018-01-01

    The European spurge hawkmoth, Hyles euphorbiae (Lepidoptera, Sphingidae), has been intensively studied as a model organism for insect chemical ecology, cold hardiness and evolution of species delineation. To understand species isolation mechanisms at a molecular level, this study aims at determining genetic factors underlying two adaptive ecological trait candidates, phorbol ester (TPA) detoxification and seasonal cold acclimation. A draft transcriptome of H. euphorbiae was generated using Illumina sequencing, providing the first genomic resource for the hawkmoth subfamily Macroglossinae. RNA expression levels in tissues of experimental TPA feeding larvae and cooled pupae was compared to levels in control larvae and pupae using 26 bp RNA sequence tag libraries (DeepSuperSAGE). Differential gene expression was assessed by homology searches of the tags in the transcriptome. In total, 389 and 605 differentially expressed transcripts for detoxification and cold hardiness, respectively, could be identified and annotated with proteins. The majority (22 of 28) of differentially expressed detox transcripts of the four 'drug metabolism' enzyme groups (cytochrome P450 (CYP), carboxylesterases (CES), glutathione S-transferases (GST) and lipases) are up-regulated. Triacylglycerol lipase was significantly over proportionally annotated among up-regulated detox transcripts. We record several up-regulated lipases, GSTe2, two CESs, CYP9A21, CYP6BD6 and CYP9A17 as candidate genes for further H. euphorbiae TPA detoxification analyses. Differential gene expression of the cold acclimation treatment is marked by metabolic depression with enriched Gene Ontology terms among down-regulated transcripts almost exclusively comprising metabolism, aerobic respiration and dissimilative functions. Down-regulated transcripts include energy expensive respiratory proteins like NADH dehydrogenase, cytochrome oxidase and ATP synthase. Gene expression patterns show shifts in carbohydrate

  16. The influence of season and living environment on children's urinary 1-hydroxypyrene levels in Ulaanbaatar, Mongolia.

    Science.gov (United States)

    Chen, Yi-Ting; Huang, Yu-Kai; Luvsan, Munkh-Erdene; Gombojav, Enkhjargal; Ochir, Chimedsuren; Bulgan, Jargal; Chan, Chang-Chuan

    2015-02-01

    Heating indoor living environments elevates air pollution in Ulaanbaatar, Mongolia. This study was conducted to investigate the influence of season and living environment on children's urinary 1-hydroxypyrene (1-OHP) levels in Ulaanbaatar, Mongolia. Our study subjects were 320 children aged 11-15 years living in gers, brick houses and apartments, in ger and non-ger areas of Ulaanbaatar. Spot urine samples and questionnaires were collected three times from each subject in three seasons, September (warm) and December (cold) in 2011 and March (moderate) in 2012. Urinary 1-OHP was analyzed by high-performance liquid chromatography with fluorescent detection (HPLC/FLD). Generalized estimating equation (GEE) models were applied to estimate the seasonal and residential effects on 1-OHP levels, adjusting for demographic and environmental factors. Children's urinary 1-OHP levels showed significant seasonal differences with 0.30 ± 0.57 μmol/mol creatinine in cold season, 0.14 ± 0.12 μmol/mol creatinine in moderate season, and 0.14 ± 0.21 μmol/mol creatinine in warm season. After controlling confounding factors, the GEE model showed that season, living area, and housing type had significant influence on children's urinary 1-OHP levels. Urinary 1-OHP levels in the cold and moderate seasons were, respectively 2.13 and 1.37 times higher than the warm season. Urinary 1-OHP levels for children living in ger areas were 1.27 times higher than those living in non-ger areas. Children who lived in gers or brick houses had 1.58 and 1.34 times higher 1-OHP levels, respectively, compared with those living in apartments. Children's urinary 1-OHP levels were associated with either estimated NO2 or SO2 concentrations at their home addresses in Ulaanbaatar. Mongolian children's urinary 1-OHP levels were significantly elevated during the cold season, and for those living in ger areas, gers, or brick houses in Ulaanbaatar. Children's urinary 1-OHP levels were associated PAH co

  17. Seasonal reversal of temperature-moisture response of net carbon exchange of biocrusted soils in a cool desert ecosystem.

    Science.gov (United States)

    Tucker, C.; Reed, S.; Howell, A.

    2017-12-01

    Carbon cycling associated with biological soil crusts, which occur in interspaces between vascular plants in drylands globally, may be an important part of the coupled climate-carbon cycle of the Earth system. A major challenge to understanding CO2 fluxes in these systems is that much of the biotic and biogeochemical activity occurs in the upper few mm of the soil surface layer (i.e., the `mantle of fertility'), which exhibits highly dynamic and difficult to measure temperature and moisture fluctuations. Here, we report data collected in a cool desert ecosystem over one year using a multi-sensor approach to simultaneously measuring temperature and moisture of the biocrust surface layer (0-2 mm), and the deeper soil profile (5-20 cm), concurrent with automated measurement of surface soil CO2 effluxes. Our results illuminate robust relationships between microclimate and field CO2 pulses that have previously been difficult to detect and explain. The temperature of the biocrust surface layer was highly variable, ranging from minimum of -9 °C in winter to maximum of 77 °C in summer with a maximum diurnal range of 61 °C. Temperature cycles were muted deeper in the soil profile. During summer, biocrust and soils were usually hot and dry and CO2 fluxes were tightly coupled to pulse wetting events experienced at the biocrust surface, which consistently resulted in net CO2 efflux (i.e., respiration). In contrast, during the winter, biocrust and soils were usually cold and moist, and there was sustained net CO2 uptake via photosynthesis by biocrust organisms, although during cold dry periods CO2 fluxes were minimal. During the milder spring and fall seasons, short wetting events drove CO2 loss, while sustained wetting events resulted in net CO2 uptake. Thus, the upper and lower bounds of net CO2 exchange at a point in time were functions of the seasonal temperature regime, while the actual flux within those bounds was determined by the magnitude and duration of biocrust

  18. Comparison of circadian, weekly, and seasonal variations of electrical storms and single events of ventricular fibrillation in patients with Brugada syndrome

    Directory of Open Access Journals (Sweden)

    Yoshiyasu Aizawa

    2016-06-01

    Full Text Available In patients with Brugada syndrome (BS, VF occurred predominantly during the nocturnal period. Some patients also developed ESs. In addition to the circadian rhythm, patients showed weekly and seasonal patterns. The patients with ESs had peak episodes of VF on Saturday and in the winter and spring, while episodes of VF in patients with single VF events occurred most often on Monday with smaller seasonal variation. Except for age, there was no difference in the clinical or ECG characteristics between the patients with ESs and those with single VF episodes.

  19. Nonbreeding-Season Drivers of Population Dynamics in Seasonal Migrants: Conservation Parallels Across Taxa

    Directory of Open Access Journals (Sweden)

    Anna M. Calvert

    2009-12-01

    Full Text Available For seasonal migrants, logistical constraints have often limited conservation efforts to improving survival and reproduction during the breeding season only. Yet, mounting empirical evidence suggests that events occurring throughout the migratory life cycle can critically alter the demography of many migrant species. Herein, we build upon recent syntheses of avian migration research to review the role of non-breeding seasons in determining the population dynamics and fitness of diverse migratory taxa, including salmonid fishes, marine mammals, ungulates, sea turtles, butterflies, and numerous bird groups. We discuss several similarities across these varied migrants: (i non-breeding survivorship tends to be a strong driver of population growth; (ii non-breeding events can affect fitness in subsequent seasons through seasonal interactions at individual- and population-levels; (iii broad-scale climatic influences often alter non-breeding resources and migration timing, and may amplify population impacts through covariation among seasonal vital rates; and (iv changes to both stationary and migratory non-breeding habitats can have important consequences for abundance and population trends. Finally, we draw on these patterns to recommend that future conservation research for seasonal migrants will benefit from: (1 more explicit recognition of the important parallels among taxonomically diverse migratory animals; (2 an expanded research perspective focused on quantification of all seasonal vital rates and their interactions; and (3 the development of detailed population projection models that account for complexity and uncertainty in migrant population dynamics.

  20. Seasonality of absolute humidity explains seasonality of influenza-like illness in Vietnam

    Directory of Open Access Journals (Sweden)

    Pham Quang Thai

    2015-12-01

    Conclusions: Our results identify a role for AH in driving the epidemiology of ILI in a tropical setting. However, in contrast to temperate regions, high rather than low AH is associated with increased ILI activity. Fluctuation in AH may be the climate factor that underlies and unifies the seasonality of ILI in both temperate and tropical regions. Alternatively, the mechanism of action of AH on disease transmission may be different in cold-dry versus hot-humid settings.

  1. [Characteristics and adaptation of seasonal drought in southern China under the background of climate change. V. Seasonal drought characteristics division and assessment in southern China].

    Science.gov (United States)

    Huang, Wan-Hua; Sui, Yue; Yang, Xiao-Guang; Dai, Shu-Wei; Li, Mao-Song

    2013-10-01

    Zoning seasonal drought based on the study of drought characteristics can provide theoretical basis for formulating drought mitigation plans and improving disaster reduction technologies in different arid zones under global climate change. Based on the National standard of meteorological drought indices and agricultural drought indices and the 1959-2008 meteorological data from 268 meteorological stations in southern China, this paper analyzed the climatic background and distribution characteristics of seasonal drought in southern China, and made a three-level division of seasonal drought in this region by the methods of combining comprehensive factors and main factors, stepwise screening indices, comprehensive disaster analysis, and clustering analysis. The first-level division was with the annual aridity index and seasonal aridity index as the main indices and with the precipitation during entire year and main crop growing season as the auxiliary indices, dividing the southern China into four primary zones, including semi-arid zone, sub-humid zone, humid zone, and super-humid zone. On this basis, the four primary zones were subdivided into nine second-level zones, including one semi-arid area-temperate-cold semi-arid hilly area in Sichuan-Yunnan Plateau, three sub-humid areas of warm sub-humid area in the north of the Yangtze River, warm-tropical sub-humid area in South China, and temperate-cold sub-humid plateau area in Southwest China, three humid areas of temperate-tropical humid area in the Yangtze River Basin, warm-tropical humid area in South China, and warm humid hilly area in Southwest China, and two super-humid areas of warm-tropical super-humid area in South China and temperate-cold super-humid hilly area in the south of the Yangtze River and Southwest China. According to the frequency and intensity of multiple drought indices, the second-level zones were further divided into 29 third-level zones. The distribution of each seasonal drought zone was

  2. Tracking the evolution of a cold stress associated gene family in cold tolerant grasses

    DEFF Research Database (Denmark)

    Sandve, Simen R; Rudi, Heidi; Asp, Torben

    2008-01-01

    to the repeat motifs of the IRI-domain in cold tolerant grasses. Finally we show that the LRR-domain of carrot and grass IRI proteins both share homology to an Arabidopsis thaliana LRR-trans membrane protein kinase (LRR-TPK). Conclusion The diverse IRI-like genes identified in this study tell a tale...... of a complex evolutionary history including birth of an ice binding domain, a burst of gene duplication events after cold tolerant grasses radiated from rice, protein domain structure differentiation between paralogs, and sub- and/or neofunctionalisation of IRI-like proteins. From our sequence analysis we...

  3. Climate Extreme Events over Northern Eurasia in Changing Climate

    Science.gov (United States)

    Bulygina, O.; Korshunova, N. N.; Razuvaev, V. N.; Groisman, P. Y.

    2014-12-01

    During the period of widespread instrumental observations in Northern Eurasia, the annual surface air temperature has increased by 1.5°C. Close to the north in the Arctic Ocean, the late summer sea ice extent has decreased by 40% providing a near-infinite source of water vapor for the dry Arctic atmosphere in the early cold season months. The contemporary sea ice changes are especially visible in the Eastern Hemisphere All these factors affect the change extreme events. Daily and sub-daily data of 940 stations to analyze variations in the space time distribution of extreme temperatures, precipitation, and wind over Russia were used. Changing in number of days with thaw over Russia was described. The total seasonal numbers of days, when daily surface air temperatures (wind, precipitation) were found to be above (below) selected thresholds, were used as indices of climate extremes. Changing in difference between maximum and minimum temperature (DTR) may produce a variety of effects on biological systems. All values falling within the intervals ranged from the lowest percentile to the 5th percentile and from the 95th percentile to the highest percentile for the time period of interest were considered as daily extremes. The number of days, N, when daily temperatures (wind, precipitation, DTR) were within the above mentioned intervals, was determined for the seasons of each year. Linear trends in the number of days were calculated for each station and for quasi-homogeneous climatic regions. Regional analysis of extreme events was carried out using quasi-homogeneous climatic regions. Maps (climatology, trends) are presented mostly for visualization purposes. Differences in regional characteristics of extreme events are accounted for over a large extent of the Russian territory and variety of its physical and geographical conditions. The number of days with maximum temperatures higher than the 95% percentile has increased in most of Russia and decreased in Siberia in

  4. Perspective Research Progress in Cold Responses of Capsella bursa-pastoris

    Directory of Open Access Journals (Sweden)

    Ali Noman

    2017-08-01

    Full Text Available Plants respond to cold stress by modulating biochemical pathways and array of molecular events. Plant morphology is also affected by the onset of cold conditions culminating at repression in growth as well as yield reduction. As a preventive measure, cascades of complex signal transduction pathways are employed that permit plants to endure freezing or chilling periods. The signaling pathways and related events are regulated by the plant hormonal activity. Recent investigations have provided a prospective understanding about plant response to cold stress by means of developmental pathways e.g., moderate growth involved in cold tolerance. Cold acclimation assays and bioinformatics analyses have revealed the role of potential transcription factors and expression of genes like CBF, COR in response to low temperature stress. Capsella bursa-pastoris is a considerable model plant system for evolutionary and developmental studies. On different occasions it has been proved that C. bursa-pastoris is more capable of tolerating cold than A. thaliana. But, the mechanism for enhanced low or freezing temperature tolerance is still not clear and demands intensive research. Additionally, identification and validation of cold responsive genes in this candidate plant species is imperative for plant stress physiology and molecular breeding studies to improve cold tolerance in crops. We have analyzed the role of different genes and hormones in regulating plant cold resistance with special reference to C. bursa-pastoris. Review of collected data displays potential ability of Capsella as model plant for improvement in cold stress regulation. Information is summarized on cold stress signaling by hormonal control which highlights the substantial achievements and designate gaps that still happen in our understanding.

  5. Catastrophic wind damage to North American forests and the potential impact of climate change

    Energy Technology Data Exchange (ETDEWEB)

    Peterson, C.J. [Department of Botany, 2502 Plant Sciences Building, University of Georgia, Athens, GA 30602-7271 (United States)

    2000-11-15

    incomplete, and climate-change model predictions sufficiently coarse, that predictions of changes in frequency, size, intensity, or timing of these extreme events must be regarded as highly uncertain. Moreover, retrospective approaches that employ tree demography and dendrochronology require prohibitively large sample sizes to resolve details of the relationship between climate fluctuations and characteristics of these storms. To improve predictions of changes in the climatology of these storms, we need improved understanding of the genesis of tornadoes and downbursts within thunderstorms, and greater resolution in global climate models. To improve coping strategies, forest scientists can contribute by giving more attention to how various silvicultural actions influence stand and tree vulnerability. Finally, increased focus on the dynamics of forest recovery and regrowth may suggest management actions that can facilitate desired objectives after one of these unpredictable wind disturbances.

  6. Seasonal changes of DNA fragmentation and quality of raw and cold-stored stallion spermatozoa.

    Science.gov (United States)

    Wach-Gygax, L; Burger, D; Malama, E; Bollwein, H; Fleisch, A; Jeannerat, E; Thomas, S; Schuler, G; Janett, F

    2017-09-01

    In this study annual fluctuations of DNA fragmentation and quality of cold-stored equine sperm were evaluated. Ejaculates were collected weekly during one year from 15 stallions. Ejaculate volume, sperm concentration and total sperm count were determined and semen was then extended and cold-stored for 48 h. Sperm motility was evaluated by CASA before and after 24 as well as 48 h of cold storage. In addition, the percentages of sperm with intact plasma membrane and acrosome (PMAI %) and with low intracellular Ca 2+ level were determined in cold-stored semen (24 h, 48 h). SCSA™ was performed to assess mean DFI, SD of DFI and % DFI in raw frozen-thawed as well as in extended sperm after 24 and 48 h of storage. The month of semen collection affected (P sperm concentration lower in summer compared to winter and motility lower in July than in any other month of the year (P sperm with low intracellular Ca +2 level (%) after storage for 24 and 48 h, higher values were measured in winter and in October compared to April, June and July (P sperm. Semen quality was impaired in midsummer when low sperm motility and viability were combined with an elevated DNA fragmentation and Ca 2+ level of sperm. Copyright © 2017. Published by Elsevier Inc.

  7. Inducing Cold-Sensitivity in the Frigophilic Fly Drosophila montana by RNAi.

    Directory of Open Access Journals (Sweden)

    Felipe M Vigoder

    Full Text Available Cold acclimation is a critical physiological adaptation for coping with seasonal cold. By increasing their cold tolerance individuals can remain active for longer at the onset of winter and can recover more quickly from a cold shock. In insects, despite many physiological studies, little is known about the genetic basis of cold acclimation. Recently, transcriptomic analyses in Drosophila virilis and D. montana revealed candidate genes for cold acclimation by identifying genes upregulated during exposure to cold. Here, we test the role of myo-inositol-1-phosphate synthase (Inos, in cold tolerance in D. montana using an RNAi approach. D. montana has a circumpolar distribution and overwinters as an adult in northern latitudes with extreme cold. We assessed cold tolerance of dsRNA knock-down flies using two metrics: chill-coma recovery time (CCRT and mortality rate after cold acclimation. Injection of dsRNAInos did not alter CCRT, either overall or in interaction with the cold treatment, however it did induced cold-specific mortality, with high levels of mortality observed in injected flies acclimated at 5°C but not at 19°C. Overall, injection with dsRNAInos induced a temperature-sensitive mortality rate of over 60% in this normally cold-tolerant species. qPCR analysis confirmed that dsRNA injection successfully reduced gene expression of Inos. Thus, our results demonstrate the involvement of Inos in increasing cold tolerance in D. montana. The potential mechanisms involved by which Inos increases cold tolerance are also discussed.

  8. The relationship of lightning activity and short-duration rainfall events during warm seasons over the Beijing metropolitan region

    Science.gov (United States)

    Wu, Fan; Cui, Xiaopeng; Zhang, Da-Lin; Qiao, Lin

    2017-10-01

    The relationship between lightning activity and rainfall associated with 2925 short-duration rainfall (SDR) events over the Beijing metropolitan region (BMR) is examined during the warm seasons of 2006-2007, using the cloud-to-ground (CG) and intracloud (IC) lightning data from Surveillance et Alerte Foudre par Interférometrie Radioélectrique (SAFIR)-3000 and 5-min rainfall data from automatic weather stations (AWSs). An optimal radius of 10 km around selected AWSs is used to determine the lightning-rainfall relationship. The lightning-rainfall correlations vary significantly, depending upon the intensity of SDR events. That is, correlation coefficient (R 0.7) for the short-duration heavy rainfall (SDHR, i.e., ≥ 20 mm h- 1) events is found higher than that (R 0.4) for the weak SDR (i.e., 5-10 mm h- 1) events, and lower percentage of the SDHR events (< 10%) than the weak SDR events (40-50%) are observed with few flashes. Significant time-lagged correlations between lightning and rainfall are also found. About 80% of the SDR events could reach their highest correlation coefficients when the associated lightning flashes shift at time lags of < 25 min before and after rainfall begins. Those events with lightning preceding rainfall account for 50-60% of the total SDR events. Better lightning-rainfall correlations can be attained when time lags are incorporated, with the use of total (CG and IC) lightning data. These results appear to have important implications for improving the nowcast of SDHR events.

  9. Heritability of cold tolerance in Nile tilapia, Oreochromis niloticus, juveniles

    NARCIS (Netherlands)

    Charo-Karisa, H.; Rezk, M.A.; Bovenhuis, H.; Komen, J.

    2005-01-01

    The inability of tilapia to tolerate low temperatures is of major economic concern as it reduces their growing season and leads to over winter mortality. In this study, cold tolerance of juvenile Nile tilapia, Oreochromis niloticus, was investigated and heritability estimates obtained. A total of 80

  10. Dynamical characteristics of the seasonal circulations over the Korea peninsula

    International Nuclear Information System (INIS)

    1989-10-01

    This paper reports dynamical characteristics of the seasonal circulations over the Korean peninsula. It consists of summary, research method, result, consideration and conclusion. It introduces the method of research ; characteristics of circulation over seasonal wind in Asia, characteristic of upper jet stream related cold wave and monsoon in East Asia and dynamics of pulsation and maintain of high atmospheric pressure in siberia in winter. It was reported by Korea science foundation in 1989.

  11. Modeled seasonality of glacial abrupt climate events

    NARCIS (Netherlands)

    Flueckiger, J.; Knutti, R.; White, J.W.C.; Renssen, H.

    2008-01-01

    Greenland ice cores, as well as many other paleo-archives from the northern hemisphere, recorded a series of 25 warm interstadial events, the so-called Dansgaard-Oeschger (D-O) events, during the last glacial period. We use the three-dimensional coupled global ocean-atmosphere-sea ice model

  12. Relative expression of genes related with cold tolerance in ...

    African Journals Online (AJOL)

    Low temperature is one of the main abiotic stresses affecting rice yield in Chile. Alterations in phenology and physiology of the crop are observed after a cold event. The objective of this work was to study the relative expression of genes related with cold stress in Chilean cultivars of rice. For this, we analyzed the expression ...

  13. Short-Term Effects of Changing Precipitation Patterns on Shrub-Steppe Grasslands: Seasonal Watering Is More Important than Frequency of Watering Events.

    Science.gov (United States)

    Densmore-McCulloch, Justine A; Thompson, Donald L; Fraser, Lauchlan H

    2016-01-01

    Climate change is expected to alter precipitation patterns. Droughts may become longer and more frequent, and the timing and intensity of precipitation may change. We tested how shifting precipitation patterns, both seasonally and by frequency of events, affects soil nitrogen availability, plant biomass and diversity in a shrub-steppe temperate grassland along a natural productivity gradient in Lac du Bois Grasslands Protected Area near Kamloops, British Columbia, Canada. We manipulated seasonal watering patterns by either exclusively watering in the spring or the fall. To simulate spring precipitation we restricted precipitation inputs in the fall, then added 50% more water than the long term average in the spring, and vice-versa for the fall precipitation treatment. Overall, the amount of precipitation remained roughly the same. We manipulated the frequency of rainfall events by either applying water weekly (frequent) or monthly (intensive). After 2 years, changes in the seasonality of watering had greater effects on plant biomass and diversity than changes in the frequency of watering. Fall watering reduced biomass and increased species diversity, while spring watering had little effect. The reduction in biomass in fall watered treatments was due to a decline in grasses, but not forbs. Plant available N, measured by Plant Root Simulator (PRS)-probes, increased from spring to summer to fall, and was higher in fall watered treatments compared to spring watered treatments when measured in the fall. The only effect observed due to frequency of watering events was greater extractable soil N in monthly applied treatments compared to weekly watering treatments. Understanding the effects of changing precipitation patterns on grasslands will allow improved grassland conservation and management in the face of global climatic change, and here we show that if precipitation is more abundant in the fall, compared to the spring, grassland primary productivity will likely be

  14. Lake seasonality across the Tibetan Plateau and their varying relationship with regional mass changes and local hydrology

    Science.gov (United States)

    Lei, Yanbin; Yao, Tandong; Yang, Kun; Sheng, Yongwei; Kleinherenbrink, Marcel; Yi, Shuang; Bird, Broxton W.; Zhang, Xiaowen; Zhu, La; Zhang, Guoqing

    2017-01-01

    The recent growth and deepening of inland lakes in the Tibetan Plateau (TP) may be a salient indicator of the consequences of climate change. The seasonal dynamics of these lakes is poorly understood despite this being potentially crucial for disentangling contributions from glacier melt and precipitation, which are all sensitive to climate, to lake water budget. Using in situ observations, satellite altimetry and gravimetry data, we identified two patterns of lake level seasonality. In the central, northern, and northeastern TP, lake levels are characterized by considerable increases during warm seasons and decreases during cold seasons, which is consistent with regional mass changes related to monsoon precipitation and evaporation. In the northwestern TP, however, lake levels exhibit dramatic increases during both warm and cold seasons, which deviate from regional mass changes. This appears to be more connected with high spring snowfall and large summer glacier melt. The variable lake level response to different drivers indicates heterogeneous sensitivity to climate change between the northwestern TP and other regions.

  15. The structure and energetics of midlatitude disturbances accompanying cold-air outbreaks over East Asia

    Science.gov (United States)

    Lau, N.-C.; Lau, K.-M.

    1984-01-01

    The evolution of extratropical transient waves as they propagate eastward from the Eurasian land mass toward the Pacific during selected cold surge events in the winter Monsoon Experiment (MONEX) is studied. The outstanding cold surge episodes during MONEX are first identified, and the salient synoptic features related to these events are described using composite streamline charts. The structure of rapidly varying disturbances accompanying the cold surges and the associated energetics are examined, and the behavior of those fluctuations over relatively longer time scales is addressed.

  16. Deep sequencing of Brachypodium small RNAs at the global genome level identifies microRNAs involved in cold stress response

    Directory of Open Access Journals (Sweden)

    Chong Kang

    2009-09-01

    Full Text Available Abstract Background MicroRNAs (miRNAs are endogenous small RNAs having large-scale regulatory effects on plant development and stress responses. Extensive studies of miRNAs have only been performed in a few model plants. Although miRNAs are proved to be involved in plant cold stress responses, little is known for winter-habit monocots. Brachypodium distachyon, with close evolutionary relationship to cool-season cereals, has recently emerged as a novel model plant. There are few reports of Brachypodium miRNAs. Results High-throughput sequencing and whole-genome-wide data mining led to the identification of 27 conserved miRNAs, as well as 129 predicted miRNAs in Brachypodium. For multiple-member conserved miRNA families, their sizes in Brachypodium were much smaller than those in rice and Populus. The genome organization of miR395 family in Brachypodium was quite different from that in rice. The expression of 3 conserved miRNAs and 25 predicted miRNAs showed significant changes in response to cold stress. Among these miRNAs, some were cold-induced and some were cold-suppressed, but all the conserved miRNAs were up-regulated under cold stress condition. Conclusion Our results suggest that Brachypodium miRNAs are composed of a set of conserved miRNAs and a large proportion of non-conserved miRNAs with low expression levels. Both kinds of miRNAs were involved in cold stress response, but all the conserved miRNAs were up-regulated, implying an important role for cold-induced miRNAs. The different size and genome organization of miRNA families in Brachypodium and rice suggest that the frequency of duplication events or the selection pressure on duplicated miRNAs are different between these two closely related plant species.

  17. Seasonal variability of stream water quality response to storm events captured using high-frequency and multi-parameter data

    Science.gov (United States)

    Fovet, O.; Humbert, G.; Dupas, R.; Gascuel-Odoux, C.; Gruau, G.; Jaffrezic, A.; Thelusma, G.; Faucheux, M.; Gilliet, N.; Hamon, Y.; Grimaldi, C.

    2018-04-01

    The response of stream chemistry to storm is of major interest for understanding the export of dissolved and particulate species from catchments. The related challenge is the identification of active hydrological flow paths during these events and of the sources of chemical elements for which these events are hot moments of exports. An original four-year data set that combines high frequency records of stream flow, turbidity, nitrate and dissolved organic carbon concentrations, and piezometric levels was used to characterize storm responses in a headwater agricultural catchment. The data set was used to test to which extend the shallow groundwater was impacting the variability of storm responses. A total of 177 events were described using a set of quantitative and functional descriptors related to precipitation, stream and groundwater pre-event status and event dynamics, and to the relative dynamics between water quality parameters and flow via hysteresis indices. This approach led to identify different types of response for each water quality parameter which occurrence can be quantified and related to the seasonal functioning of the catchment. This study demonstrates that high-frequency records of water quality are precious tools to study/unique in their ability to emphasize the variability of catchment storm responses.

  18. Dynamics of 2013 Sudden Stratospheric Warming event and its impact on cold weather over Eurasia: Role of planetary wave reflection.

    Science.gov (United States)

    Nath, Debashis; Chen, Wen; Zelin, Cai; Pogoreltsev, Alexander Ivanovich; Wei, Ke

    2016-04-07

    In the present study, we investigate the impact of stratospheric planetary wave reflection on tropospheric weather over Central Eurasia during the 2013 Sudden Stratospheric Warming (SSW) event. We analyze EP fluxes and Plumb wave activity fluxes to study the two and three dimensional aspects of wave propagation, respectively. The 2013 SSW event is excited by the combined influence of wavenumber 1 (WN1) and wavenumber 2 (WN2) planetary waves, which makes the event an unusual one and seems to have significant impact on tropospheric weather regime. We observe an extraordinary development of a ridge over the Siberian Tundra and the North Pacific during first development stage (last week of December 2012) and later from the North Atlantic in the second development stage (first week of January 2013), and these waves appear to be responsible for the excitation of the WN2 pattern during the SSW. The wave packets propagated upward and were then reflected back down to central Eurasia due to strong negative wind shear in the upper stratospheric polar jet, caused by the SSW event. Waves that propagated downward led to the formation of a deep trough over Eurasia and brought extreme cold weather over Kazakhstan, the Southern part of Russia and the Northwestern part of China during mid-January 2013.

  19. Seasonality of absolute humidity explains seasonality of influenza-like illness in Vietnam.

    Science.gov (United States)

    Thai, Pham Quang; Choisy, Marc; Duong, Tran Nhu; Thiem, Vu Dinh; Yen, Nguyen Thu; Hien, Nguyen Tran; Weiss, Daniel J; Boni, Maciej F; Horby, Peter

    2015-12-01

    Experimental and ecological studies have shown the role of climatic factors in driving the epidemiology of influenza. In particular, low absolute humidity (AH) has been shown to increase influenza virus transmissibility and has been identified to explain the onset of epidemics in temperate regions. Here, we aim to study the potential climatic drivers of influenza-like illness (ILI) epidemiology in Vietnam, a tropical country characterized by a high diversity of climates. We specifically focus on quantifying and explaining the seasonality of ILI. We used 18 years (1993-2010) of monthly ILI notifications aggregated by province (52) and monthly climatic variables (minimum, mean, maximum temperatures, absolute and relative humidities, rainfall and hours of sunshine) from 67 weather stations across Vietnam. Seasonalities were quantified from global wavelet spectra, using the value of the power at the period of 1 year as a measure of the intensity of seasonality. The 7 climatic time series were characterized by 534 summary statistics which were entered into a regression tree to identify factors associated with the seasonality of AH. Results were extrapolated to the global scale using simulated climatic times series from the NCEP/NCAR project. The intensity of ILI seasonality in Vietnam is best explained by the intensity of AH seasonality. We find that ILI seasonality is weak in provinces experiencing weak seasonal fluctuations in AH (annual power power >17.6). In Vietnam, AH and ILI are positively correlated. Our results identify a role for AH in driving the epidemiology of ILI in a tropical setting. However, in contrast to temperate regions, high rather than low AH is associated with increased ILI activity. Fluctuation in AH may be the climate factor that underlies and unifies the seasonality of ILI in both temperate and tropical regions. Alternatively, the mechanism of action of AH on disease transmission may be different in cold-dry versus hot-humid settings

  20. The European Market for Seasonal Gas Storage

    International Nuclear Information System (INIS)

    Mahan, A.

    2006-02-01

    European demand for gas will grow in the years to come. Simultaneously, gas production in Europe will decrease and imported gas will be needed to replace indigenous production. Gas demand is not constant during the year. There are variations in demand on different timescales ranging from seasonal to hourly. Variations in demand are characterised by two main parameters: working volume and deliverability. Working volume - the amount of gas that can be supplied above the baseload production volume during a long (cold) period- is primarily needed to cope with the summer-winter pattern of gas consumption. Most of the summer-winter pattern comes from the temperature sensitive gas consumption by households and service industries. Gas usage by industry and the power sector are more evenly spread throughout the year and need less working volume. Deliverability - the amount of gas per hour that can be generated on a (very) cold day above the baseload capacity - is the ability to produce large volumes during short periods, e.g. for extremely cold days, or during peak periods during a day. In this paper we argue that a large amount of additional working volume will be required over the coming years. First, flexible European production will be replaced by long-distance import gas, and second, the gas market is expected to grow further. Todays market appears focus mainly on cavems for storage volume. Cavems have little working volume but are ideal for trading purposes. Consequently, Europe may be facing a deficit in working volume, i.e. the ability to cope with seasonal changes in demand. This paper aims to widen the discussion of this matter and give rise to this concern by setting out a broad analysis, exploring the market drivers for seasonal storage and identifying the public interest issues for this market. Chapter 2 gives an overview of demand for and supply characteristics of gas flexibility. Chapter 3 describes the role of gas storage facilities in the gas market

  1. Overwintering biology and limits of cold tolerance in larvae of pistachio twig borer, Kermania pistaciella.

    Science.gov (United States)

    Mollaei, M; Izadi, H; Šimek, P; Koštál, V

    2016-08-01

    Pistachio twig borer, Kermania pistaciella is an important pest of pistachio trees. It has an univoltine life-cycle and its larvae tunnel and feed inside pistachio twigs for almost 10 months each year. The last larval instars overwinter inside the twigs. Survival/mortality associated with low temperatures during overwintering stage is currently unknown. We found that overwintering larvae of the Rafsanjan (Iran) population of K. pistaciella rely on maintaining a stably high supercooling capacity throughout the cold season. Their supercooling points (SCPs) ranged between -19.4 and -22.7°C from October to February. Larvae were able to survive 24 h exposures to -15°C anytime during the cold season. During December and January, larvae were undergoing quiescence type of dormancy caused probably by low ambient temperatures and/or changes in host tree physiology (tree dormancy). Larvae attain highest cold tolerance (high survival at -20°C) during dormancy, which offers them sufficient protection against geographically and ecologically relevant cold spells. High cold tolerance during dormancy was not associated with accumulation of any low-molecular mass cryoprotective substances. The SCP sets the limit of cold tolerance in pistachio twig borer, meaning that high mortality of overwintering populations can be expected only in the regions or years where or when the temperatures fall below the average larval SCP (i.e., below -20°C). Partial mortality can be expected also when temperatures repeatedly drop close to the SCP on a diurnal basis.

  2. Final Scientific/Technical Report for Subseasonal to Seasonal Prediction of Extratropical Storm Track Activity over the U.S. using NMME data

    Energy Technology Data Exchange (ETDEWEB)

    Chang, Edmund Kar-Man [Stony Brook Univ., NY (United States)

    2017-10-30

    The goals of the project are: 1) To develop and assess subseasonal to seasonal prediction products for storm track activity derived from NMME data; 2) Assess how much of the predictable signal can be associated with ENSO and other modes of large scale low frequency atmosphere-ocean variability; and 3) Further explore the link between storm track variations and extreme weather statistics. Significant findings of this project include the followings: 1) Our assessment of NMME reforecasts of storm track variability has demonstrated that NMME models have substantial skill in predicting storm track activity in the vicinity of North America - Subseasonal skill is high only for leads of less than 1 month. However, seasonal (winter) prediction skill near North America is high even out to 4 to 5 months lead - Much of the skill for leads of 1 month or longer is related to the influence of ENSO - Nevertheless, lead 0 NMME predictions are significantly more skillful than those based on ENSO influence 2) Our results have demonstrated that storm track variations highly modulate the frequency of occurrence of weather extremes - Extreme cold, high wind, and extreme precipitation events in winter - Extreme heat events in summer - These results suggest that NMME storm track predictions can be developed to serve as a useful guidance to assist the formulation of monthly/seasonal outlooks

  3. Investigation on seasonal variation of thermal-induced strain in flexible pavements based on field and laboratory measurements

    Directory of Open Access Journals (Sweden)

    Simita Biswas

    2016-09-01

    Full Text Available Pavement temperature variation has a large influence on the structural response of flexible pavements. Daily and seasonal temperature fluctuation causes expansion and contraction of pavement material, which then leads to the generation of thermal strain. In this study, field observation and laboratory tests were conducted to investigate seasonal variation of thermal-induced strain in flexible pavement. Field observations were conducted at the Integrated Road Research Facility (IRRF’s test road in Edmonton, Alberta, Canada, which is fully equipped with structural and environmental monitoring instruments. The main objective of the field study was to compare the variation of thermal-induced strain in warm and cold seasons. Field results indicated that thermal-induced strain is 1.4–2.0 times greater in cold seasons than in warm seasons following the same pavement temperature variations; however, strain generation rate was greater in warm seasons. Laboratory testing of asphalt slab and cylindrical samples produced comparable ratios. Moreover, field observation and laboratory testing showed a similar trend of temperature and thermal strain variations. Keywords: Thermal-induced strain, Asphalt strain gauge, Field observation, Flexible pavement, Laboratory testing, Seasonal variation

  4. Evaluation of seasonal exergy efficiency of air handing unit

    Directory of Open Access Journals (Sweden)

    Kęstutis Genys

    2015-10-01

    Full Text Available The article deals with the air handling unit seasonal exergy efficiency. TRNSYS simulation tool is used to evaluate it. The object of research is air treatment device used to treat an air for the ventilation of laboratory. The mathematical model of air handling unit using TRNSYS simulation tool was developed when the technical parameters of air handling unit and energy exchange in it were analysed. The developed model according to the made observations during the warm and cold periods was tested and validation of elements was performed. The simulation of air handling unit operation after the verification of reliability and permitted tolerances was performed. The control mechanisim which allows simulating the operation of air handling unit during cold and warm periods of the year was made. The mathematical algorithm for calculation of air handling unit exergy efficiency coefficient applying the principles of exergy analysis was developed. The seasonal exergy efficiency of air handling unit equal to 3.94 percent during the simulation was obtained.

  5. Seasonal Accumulation and Depletion of Local Sediment Stores of Four Headwater Catchments

    Directory of Open Access Journals (Sweden)

    Sarah E. Martin

    2014-07-01

    Full Text Available Seasonal turbidity patterns and event-level hysteresis analysis of turbidity verses discharge in four 1 km2 headwater catchments in California’s Sierra Nevada indicate localized in-channel sediment sources and seasonal accumulation-depletion patterns of stream sediments. Turbidity signals were analyzed for three years in order to look at the relationships between seasonal turbidity trends, event turbidity patterns, and precipitation type to stream sediment production and transport. Seasonal patterns showed more turbidity events associated with fall and early to mid- winter events than with peak snow-melt. No significant turbidity patterns emerged for periods of snow melt vs. rain. Single event hysteresis loops showed clockwise patterns were dominant suggesting local sediment sources. In successive discharge events, the largest turbidity spike was often associated with the first but not necessarily the largest discharge event-indicating seasonal depletion of local sediment stores. In multi-peaked discharge events, hysteresis loops shifted from clockwise to linear or random patterns suggesting that localized sediment stores are being used up and sufficient flow energy must be reached to start entraining the more consolidated bank/bed sediment or that dominant sediment sources may be shifting to less localized areas such as hill slopes. A conceptual model with phases of accumulation and transport is proposed.

  6. Seasonality in mortality and its relationship to temperature among the older population in Hanoi, Vietnam

    Directory of Open Access Journals (Sweden)

    Le Thi Thanh Xuan

    2014-12-01

    Full Text Available Background: Several studies have established a relationship between temperature and mortality. In particular, older populations have been shown to be vulnerable to temperature effects. However, little information exists on the temperature–mortality relationship in Vietnam. Objectives: This article aims to examine the monthly temperature–mortality relationship among older people in Hanoi, Vietnam, over the period between 2005 and 2010, and estimate seasonal patterns in mortality. Methods: We employed Generalized Additive Models, including smooth functions, to model the temperature–mortality relationships. A quasi-Poisson distribution was used to model overdispersion of death counts. Temporal trends, seasonality, and population size were adjusted for while estimating changes in monthly mortality over the study period. A cold month was defined as a month with a mean temperature below 19°C. Results: This study found that the high peak of mortality coincided with low temperatures in the month of February 2008, during which the mean temperature was the lowest in the whole study period. There was a significant relationship between mean monthly temperature and mortality among the older people (p<0.01. Overall, there was a significant decrease in the number of deaths in the year 2009 during the study period. There was a 21% increase in the number of deaths during the cold season compared to the warm season. The increase in mortality during the cold period was higher among females compared to males (female: IRR [incidence relative risk] =1.23; male: IRR=1.18. Conclusions: Cold temperatures substantially increased mortality among the older population in Hanoi, Vietnam, and there were gender differences. Necessary preventive measures are required to mitigate temperature effects with greater attention to vulnerable groups.

  7. Rethinking Little Rock: The Cold War Politics of School Integration in the United States

    Science.gov (United States)

    Dejong-Lambert, William

    2007-01-01

    Though the impact of the cold war on the civil rights movement continued long after the desegregation crisis in Little Rock, the timing of the events in Arkansas, particularly the events at Central High School, constituted a unique moment in the history of the cold war. Up until the fall of 1957, the Soviet Union had been perceived as less…

  8. Burden and seasonality of testicular torsion in tropical Africa ...

    African Journals Online (AJOL)

    Jibril O. Bello

    2018-02-14

    Feb 14, 2018 ... Department of Surgery, University of Ilorin Teaching Hospital, Ilorin, Nigeria ... Cases occurred 91% higher than average during the cold season (November to .... tion strategies through the education of school staff and students on .... torsion and weather conditions: analysis of 21,289 cases in Brazil. Int.

  9. Higgsino cold dark matter motivated by collider data

    International Nuclear Information System (INIS)

    Kane, G.L.; Wells, J.D.

    1996-01-01

    Motivated by a supersymmetric interpretation of the CDF eeγγ+E/ T event and the reported Z→ bar bb excess at LEP, we analyze the implied Higgsino-like lightest supersymmetric partner as a cold dark matter candidate. We examine constraints and calculate its relic density, obtaining 0.05 2 <1. Thus it is a viable cold dark matter candidate, and we discuss its favorable prospects for laboratory detection. copyright 1996 The American Physical Society

  10. Investigating temperature breaks in the summer fruit export cold chain: A case study

    Directory of Open Access Journals (Sweden)

    Heinri W. Freiboth

    2013-11-01

    Full Text Available There is concern in the South African fruit industry that a large amount of fruit and money is lost every season due to breaks in the fruit export cold chain. The possibility of a large percentage of losses in a significant sector of the economy warranted further investigation. This article attempted to highlight some of the possible problem areas in the cold chain, from the cold store to the port, by analysing historic temperature data from different fruit export supply chains of apples, pears and grapes. In addition, a trial shipment of apples was used to investigate temperature variation between different pallets in the same container. This research has added value to the South African fruit industry by identifying the need to improve operational procedures in the cold chain.

  11. Public Perception of Extreme Cold Weather-Related Health Risk in a Cold Area of Northeast China.

    Science.gov (United States)

    Ban, Jie; Lan, Li; Yang, Chao; Wang, Jian; Chen, Chen; Huang, Ganlin; Li, Tiantian

    2017-08-01

    A need exists for public health strategies regarding extreme weather disasters, which in recent years have become more frequent. This study aimed to understand the public's perception of extreme cold and its related health risks, which may provide detailed information for public health preparedness during an extreme cold weather event. To evaluate public perceptions of cold-related health risk and to identify vulnerable groups, we collected responses from 891 participants in a face-to-face survey in Harbin, China. Public perception was measured by calculating the score for each perception question. Locals perceived that extreme cold weather and related health risks were serious, but thought they could not avoid these risks. The significant difference in perceived acceptance level between age groups suggested that the elderly are a "high health risk, low risk perception" group, meaning that they are relatively more vulnerable owing to their high susceptibility and low awareness of the health risks associated with extreme cold weather. The elderly should be a priority in risk communication and health protective interventions. This study demonstrated that introducing risk perception into the public health field can identify vulnerable groups with greater needs, which may improve the decision-making of public health intervention strategies. (Disaster Med Public Health Preparedness. 2017;11:417-421).

  12. Seasonal Scale Convective-Stratiform Pricipitation Variabilities at Tropics

    Science.gov (United States)

    S, Sreekanth T.

    begin{center} Large Seasonal Scale Convective-Stratiform Pricipitation Variabilities at Tropics Sreekanth T S*, Suby Symon*, G. Mohan Kumar (1) and V Sasi Kumar (2) *Centre for Earth Science Studies, Akkulam, Thiruvananthapuram (1) D-330, Swathi Nagar, West Fort, Thiruvananthapuram 695023 (2) 32. NCC Nagar Peroorkada, Thiruvananthapuram ABSTRACT This study investigates the variabilities of convective and stratiform rainfall from 2011 to 2013 at a tropical coastal station in three seasons viz Pre-Monsoon (March-May), Monsoon (June-September) and Post-Monsoon (October-December). Understanding the climatological variability of these two dominant forms of precipitation and their implications in the total rainfall were the main objectives of this investigation. Variabilities in the frequency & duration of events, rain rate & total number of rain drops distribution in different events and the accumulated amount of rain water were analysed. Based on the ground & radar observations from optical & impact disdrometers, Micro Rain Radar and Atmospheric Electric Field Mill, precipitation events were classified into convective and stratiform in three seasons. Classification was done by the method followed by Testud et al (2001) and as an additional information electrical behaviour of clouds from Atmospheric Electric Field Mill is also used. Events which could not be included in both types were termed as 'mixed precipitation' and were included separately. Diurnal variability of the total rainfall in each seasons were also examined. For both convective and stratiform rainfall there exist distinct day-night differences. During nocturnal hours convective rain draged more attention. In all seasons almost 70% of rain duration and 60% of rain events of convective origin were confined to nocturnal hours. But stratiform rain was not affected by diurnal variations greatly because night time occurrences of stratiform duration and events were less than 50%. Also in Monsoon above 35% of

  13. Pattern of xylem phenology in conifers of cold ecosystems at the Northern Hemisphere.

    Science.gov (United States)

    Rossi, Sergio; Anfodillo, Tommaso; Čufar, Katarina; Cuny, Henri E; Deslauriers, Annie; Fonti, Patrick; Frank, David; Gričar, Jožica; Gruber, Andreas; Huang, Jian-Guo; Jyske, Tuula; Kašpar, Jakub; King, Gregory; Krause, Cornelia; Liang, Eryuan; Mäkinen, Harri; Morin, Hubert; Nöjd, Pekka; Oberhuber, Walter; Prislan, Peter; Rathgeber, Cyrille B K; Saracino, Antonio; Swidrak, Irene; Treml, Václav

    2016-11-01

    The interaction between xylem phenology and climate assesses forest growth and productivity and carbon storage across biomes under changing environmental conditions. We tested the hypothesis that patterns of wood formation are maintained unaltered despite the temperature changes across cold ecosystems. Wood microcores were collected weekly or biweekly throughout the growing season for periods varying between 1 and 13 years during 1998-2014 and cut in transverse sections for assessing the onset and ending of the phases of xylem differentiation. The data set represented 1321 trees belonging to 10 conifer species from 39 sites in the Northern Hemisphere and covering an interval of mean annual temperature exceeding 14 K. The phenological events and mean annual temperature of the sites were related linearly, with spring and autumnal events being separated by constant intervals across the range of temperature analysed. At increasing temperature, first enlarging, wall-thickening and mature tracheids appeared earlier, and last enlarging and wall-thickening tracheids occurred later. Overall, the period of wood formation lengthened linearly with the mean annual temperature, from 83.7 days at -2 °C to 178.1 days at 12 °C, at a rate of 6.5 days °C -1 . April-May temperatures produced the best models predicting the dates of wood formation. Our findings demonstrated the uniformity of the process of wood formation and the importance of the environmental conditions occurring at the time of growth resumption. Under warming scenarios, the period of wood formation might lengthen synchronously in the cold biomes of the Northern Hemisphere. © 2016 John Wiley & Sons Ltd.

  14. Adverse moisture events predict seasonal abundance of Lyme disease vector ticks (Ixodes scapularis)

    Science.gov (United States)

    Berger, Kathryn A.; Ginsberg, Howard S.; Dugas, Katherine D.; Hamel, Lutz H.; Mather, Thomas N.

    2014-01-01

    Background: Lyme borreliosis (LB) is the most commonly reported vector-borne disease in north temperate regions worldwide, affecting an estimated 300,000 people annually in the United States alone. The incidence of LB is correlated with human exposure to its vector, the blacklegged tick (Ixodes scapularis). To date, attempts to model tick encounter risk based on environmental parameters have been equivocal. Previous studies have not considered (1) the differences between relative humidity (RH) in leaf litter and at weather stations, (2) the RH threshold that affects nymphal blacklegged tick survival, and (3) the time required below the threshold to induce mortality. We clarify the association between environmental moisture and tick survival by presenting a significant relationship between the total number of tick adverse moisture events (TAMEs - calculated as microclimatic periods below a RH threshold) and tick abundance each year.Methods: We used a 14-year continuous statewide tick surveillance database and corresponding weather data from Rhode Island (RI), USA, to assess the effects of TAMEs on nymphal populations of I. scapularis. These TAMEs were defined as extended periods of time (>8 h below 82% RH in leaf litter). We fit a sigmoid curve comparing weather station data to those collected by loggers placed in tick habitats to estimate RH experienced by nymphal ticks, and compiled the number of historical TAMEs during the 14-year record.Results: The total number of TAMEs in June of each year was negatively related to total seasonal nymphal tick densities, suggesting that sub-threshold humidity episodes >8 h in duration naturally lowered nymphal blacklegged tick abundance. Furthermore, TAMEs were positively related to the ratio of tick abundance early in the season when compared to late season, suggesting that lower than average tick abundance for a given year resulted from tick mortality and not from other factors.Conclusions: Our results clarify the mechanism

  15. Plasticity and stress tolerance override local adaptation in the responses of Mediterranean holm oak seedlings to drought and cold.

    Science.gov (United States)

    Gimeno, Teresa E; Pías, Beatriz; Lemos-Filho, José P; Valladares, Fernando

    2009-01-01

    Plant populations of widely distributed species experience a broad range of environmental conditions that can be faced by phenotypic plasticity or ecotypic differentiation and local adaptation. The strategy chosen will determine a population's ability to respond to climate change. To explore this, we grew Quercus ilex (L.) seedlings from acorns collected at six selected populations from climatically contrasting localities and evaluated their response to drought and late season cold events. Maximum photosynthetic rate (A(max)), instantaneous water use efficiency (iWUE), and thermal tolerance to freeze and heat (estimated from chlorophyll fluorescence versus temperature curves) were measured in 5-month-old seedlings in control (no stress), drought (water-stressed), and cold (low suboptimal temperature) conditions. The observed responses were similar for the six populations: drought decreased A(max) and increased iWUE, and cold reduced A(max) and iWUE. All the seedlings maintained photosynthetic activity under adverse conditions (drought and cold), and rapidly increased their iWUE by closing stomata when exposed to drought. Heat and freeze tolerances were similarly high for seedlings from all the populations, and they were significantly increased by drought and cold, respectively; and were positively related to each other. Differences in seedling performance across populations were primarily induced by maternal effects mediated by seed size and to a lesser extent by idiosyncratic physiologic responses to drought and low temperatures. Tolerance to multiple stresses together with the capacity to physiologically acclimate to heat waves and cold snaps may allow Q. ilex to cope with the increasingly stressful conditions imposed by climate change. Lack of evidence of physiologic seedling adaptation to local climate may reflect opposing selection pressures to complex, multidimensional environmental conditions operating within the distribution range of this species.

  16. The relationship of lightning activity and short-duation rainfall events during warm seasons over the Beijing metropolitan region

    Science.gov (United States)

    Wu, F.; Cui, X.; Zhang, D. L.; Lin, Q.

    2017-12-01

    The relationship between lightning activity and rainfall associated with 2925 short-duration rainfall (SDR) events over the Beijing metropolitan region (BMR) is examined during the warm seasons of 2006-2007, using the cloud-to-ground (CG) and intracloud (IC) lightning data from Surveillance et Alerte Foudre par Interférometrie Radioélectrique (SAFIR)-3000 and 5-min rainfall data from automatic weather stations (AWSs). To facilitate the analysis of the rainfall-lightning correlations, the SDR events are categorized into six different intensity grades according to their hourly rainfall rates (HRRs), and an optimal radius of 10 km from individual AWSs for counting their associated lightning flashes is used. Results show that the lightning-rainfall correlations vary significantly with different intensity grades. Weak correlations (R 0.4) are found in the weak SDR events, and 40-50% of the events are no-flash ones. And moderate correlation (R 0.6) are found in the moderate SDR events, and > 10-20% of the events are no-flash ones. In contrast, high correlations (R 0.7) are obtained in the SDHR events, and < 10% of the events are no-flash ones. The results indicate that lightning activity is observed more frequently and correlated more robust with the rainfall in the SDHR events. Significant time lagged correlations between lightning and rainfall are also found. About 80% of the SDR events could reach their highest correlation coefficients when the associated lightning flashes shift at time lags of < 25 min before and after rainfall begins. The percentages of SDR events with CG or total lightning activity preceding, lagging or coinciding with rainfall shows that (i) in about 55% of the SDR events lightning flashes preceded rainfall; (ii) the SDR events with lightning flashes lagging behind rainfall accounted for about 30%; and (iii) the SDR events without any time shifts accounted for the remaining 15%. Better lightning-rainfall correlations can be attained when time

  17. Detection of cold pain, cold allodynia and cold hyperalgesia in freely behaving rats

    Directory of Open Access Journals (Sweden)

    Woolf Clifford J

    2005-12-01

    Full Text Available Abstract Background Pain is elicited by cold, and a major feature of many neuropathic pain states is that normally innocuous cool stimuli begin to produce pain (cold allodynia. To expand our understanding of cold induced pain states we have studied cold pain behaviors over a range of temperatures in several animal models of chronic pain. Results We demonstrate that a Peltier-cooled cold plate with ± 1°C sensitivity enables quantitative measurement of a detection withdrawal response to cold stimuli in unrestrained rats. In naïve rats the threshold for eliciting cold pain behavior is 5°C. The withdrawal threshold for cold allodynia is 15°C in both the spared nerve injury and spinal nerve ligation models of neuropathic pain. Cold hyperalgesia is present in the spared nerve injury model animals, manifesting as a reduced latency of withdrawal response threshold at temperatures that elicit cold pain in naïve rats. We also show that following the peripheral inflammation produced by intraplantar injection of complete Freund's adjuvant, a hypersensitivity to cold occurs. Conclusion The peltier-cooled provides an effective means of assaying cold sensitivity in unrestrained rats. Behavioral testing of cold allodynia, hyperalgesia and pain will greatly facilitate the study of the neurobiological mechanisms involved in cold/cool sensations and enable measurement of the efficacy of pharmacological treatments to reduce these symptoms.

  18. Seasonal reversal at Miryang Eoreumgol (Ice Valley), Korea: observation and monitoring

    Science.gov (United States)

    Byun, Hi-Ryong; Tanaka, Hiroshi L.; Choi, Pom-Yong; Kim, Do-Woo

    2011-12-01

    We investigate an anomalous phenomenon evident in the Miryang Eoreumgol (Ice Valley), Korea: The wind and water are cold during summer and warm during winter, and ice formation does not occur in winter but in summer. We have initiated observations and investigations into the origin of heat sources particularly with regard to the mechanism of ice formation in summer. Previous theories, e.g., concerning underground gravity currents, water evaporation, diurnal and seasonal respirations of the talus, effects of ground heat, radiation and topography, etc., are considered. After a calculation of heat sources, we propose two new concepts—a repetitious heat separation mechanism and a positive feedback mechanism of cold air generation—to demonstrate that the heat mechanism of the seasonal reversal of the ice valley may be controlled by the use of the phase change between ice and water vapor with only a small amount of additional unknown energy.

  19. Cold - an underrated risk factor for health

    International Nuclear Information System (INIS)

    Mercer, James B.

    2003-01-01

    Cardiovascular diseases (CVD) are responsible for around 20% of all deaths worldwide (approximately 14 million) and are the principal cause of death in all developed countries, accounting for 50% of all deaths. Variations in the annual per capita death rates in different countries are well documented. Less well known are seasonal variations in death rates, with the highest levels occurring during the colder winter months, which have been described in many countries. This phenomenon is referred to as excess winter mortality. CVD-related deaths account for the majority of excess winter deaths (up to 70% in some countries), while about half of the remaining are due to increases in respiratory diseases. Paradoxically, CVD mortality increases to a greater extent with a given fall in temperature in regions with warm winters. While much of the indirect evidence points to the notion that cold is somehow involved in explaining excess winter deaths, the mechanism by which seemingly mild exposure to cold ambient conditions can increase the risk of death remains unclear. The strong indirect epidemiological evidence coupling cold climate to mortality may be related to indoor rather than outdoor climatic conditions (e.g., cold/damp houses versus arm/dry houses) coupled with a plethora of factors including health status, ageing-related deterioration in physiological and behavioral thermoregulation, toxicology, and socioeconomic factors

  20. Link between western Arabian sea surface temperature and summer monsoon strength and high-latitude abrupt climate events

    Digital Repository Service at National Institute of Oceanography (India)

    Naidu, P.D.

    Artificial Neural Networks (ANN's) based on quantitative analyses of planktic foraminifera. High seasonal SST contrast between winter and summer during the last glacial period indicates weak upwelling and strong cold northeasterly winds. Minimum seasonal SST...

  1. Seasonal trends of atmospheric nitrogen dioxide and sulfur dioxide over North Santa Clara, Cuba.

    Science.gov (United States)

    Alejo, Daniellys; Morales, Mayra C; de la Torre, Jorge B; Grau, Ricardo; Bencs, László; Van Grieken, René; Van Espen, Piet; Sosa, Dismey; Nuñez, Vladimir

    2013-07-01

    Atmospheric nitrogen dioxide (NO2) and sulfur dioxide (SO2) levels were monitored simultaneously by means of Radiello passive samplers at six sites of Santa Clara city, Cuba, in the cold and the warm seasons in 2010. The dissolved ionic forms of NO2 and SO2 as nitrate and sulfite plus sulfate, respectively, were determined by means of ion chromatography. Analysis of NO2 as nitrite was also performed by UV-Vis spectrophotometry. For NO2, significant t tests show good agreement between the results of IC and UV-Vis methods. The NO2 and SO2 concentrations peaked in the cold season, while their minimum levels were experienced in the warm season. The pollutant levels do not exceed the maximum allowable limit of the Cuban Standard 39:1999, i.e., 40 μg/m(3) and 50 μg/m(3) for NO2 and SO2, respectively. The lowest pollutant concentrations obtained in the warm season can be attributed to an increase in their removal via precipitation (scavenging) while to the decreased traffic density and industrial emission during the summer holidays (e.g., July and August).

  2. Spatial Distribution and Semiannual Variation of Cold-Dense Plasma Sheet

    Science.gov (United States)

    Bai, Shichen; Shi, Quanqi; Tian, Anmin; Nowada, Motoharu; Degeling, Alexander W.; Zhou, Xu-Zhi; Zong, Qiu-Gang; Rae, I. Jonathan; Fu, Suiyan; Zhang, Hui; Pu, Zuyin; Fazakerly, Andrew N.

    2018-01-01

    The cold-dense plasma sheet (CDPS) plays an important role in the entry process of the solar wind plasma into the magnetosphere. Investigating the seasonal variation of CDPS occurrences will help us better understand the long-term variation of plasma exchange between the solar wind and magnetosphere, but any seasonal variation of CDPS occurrences has not yet been reported in the literature. In this paper, we investigate the seasonal variation of the occurrence rate of CDPS using Geotail data from 1996 to 2015 and find a semiannual variation of the CDPS occurrences. Given the higher probability of solar wind entry under stronger northward interplanetary magnetic field (IMF) conditions, 20 years of IMF data (1996-2015) are used to investigate the seasonal variation of IMF Bz under northward IMF conditions. We find a semiannual variation of IMF Bz, which is consistent with the Russell-McPherron (R-M) effect. We therefore suggest that the semiannual variation of CDPS may be related to the R-M effect.

  3. Seven cases of upper gastrointestinal bleeding after cold biopsy

    OpenAIRE

    Alneaimi, Khaled; Abdelmoula, Ali; Vincent, Magalie; Savale, Camille; Baye, Birane; Lesur, Gilles

    2016-01-01

    Background and study aims: Routine biopsy of the upper gastrointestinal tract is performed with increasing frequency. It is generally considered to be safe without significant complication. However, gastrointestinal bleeding as a result of cold biopsy is a known complication. We report seven cases of upper gastrointestinal bleeding after cold biopsy and discuss clinical data, risks factors, severity and management of this event. We suggest that physicians must be more cautious with this rare ...

  4. The burden of seasonal respiratory infections on a national telehealth service in England.

    Science.gov (United States)

    Morbey, R A; Harcourt, S; Pebody, R; Zambon, M; Hutchison, J; Rutter, J; Thomas, H; Smith, G E; Elliot, A J

    2017-07-01

    Seasonal respiratory illnesses present a major burden on primary care services. We assessed the burden of respiratory illness on a national telehealth system in England and investigated the potential for providing early warning of respiratory infection. We compared weekly laboratory reports for respiratory pathogens with telehealth calls (NHS 111) between week 40 in 2013 and week 29 in 2015. Multiple linear regression was used to identify which pathogens had a significant association with respiratory calls. Children aged respiratory pathogens explained over 83% of the variation in cold/flu, cough and difficulty breathing calls. Based on the first two seasons available, the greatest burden was associated with respiratory syncytial virus (RSV) and influenza, with associations found in all age bands. The most sensitive signal for influenza was calls for 'cold/flu', whilst for RSV it was calls for cough. The best-fitting models showed calls increasing a week before laboratory specimen dates. Daily surveillance of these calls can provide early warning of seasonal rises in influenza and RSV, contributing to the national respiratory surveillance programme.

  5. Cold season Africa-Asia multidecadal teleconnection pattern and its relation to the Atlantic multidecadal variability

    Science.gov (United States)

    Sun, Cheng; Li, Jianping; Ding, Ruiqiang; Jin, Ze

    2017-06-01

    A prominent teleconnection pattern of multidecadal variability of cold season (November to April) upper-level atmospheric circulation over North Africa and Eurasia (NA-EA) is revealed by empirical orthogonal function analysis of the Twentieth Century Reanalysis data. This teleconnection pattern is characterized by an eastward propagating wave train with a zonal wavenumber of 5-6 between 20° and 40°N, extending from the northwest coast of Africa to East Asia, and thus is referred to as the Africa-Asia multidecadal teleconnection pattern (AAMT). One-point correlation maps show that the teleconnectivity of AAMT is strong and further demonstrate the existence of the AAMT. The AAMT shapes the spatial structure of multidecadal change in atmospheric circulation over the NA-EA region, and in particular the AAMT pattern and associated fields show similar structures to the change occurring around the early 1960s. A strong in-phase relationship is observed between the AAMT and Atlantic multidecadal variability (AMV) and this connection is mainly due to Rossby wave dynamics. Barotropic modeling results suggest that the upper-level Rossby wave source generated by the AMV can excite the AAMT wave train, and Rossby wave ray tracing analysis further highlights the role of the Asian jet stream in guiding the wave train to East Asia. The AAMT acts as an atmospheric bridge conveying the influence of AMV onto the downstream multidecadal climate variability. The AMV is closely related to the coordinated change in surface and tropospheric air temperatures over Northwest Africa, the Arabian Peninsula and Central China, which may result from the adiabatic expansion/compression of air associated with the AAMT.

  6. Seasonal variation of the protozooplanktonic community in a tropical oligotrophic environment (Ilha Solteira reservoir, Brazil).

    Science.gov (United States)

    Mansano, A S; Hisatugo, K F; Leite, M A; Luzia, A P; Regali-Seleghim, M H

    2013-05-01

    The seasonal variation of the protozooplanktonic community (ciliates and testate amoebae) was studied in a tropical oligotrophic reservoir in Brazil, which was under the influence of two contrasting climatic seasons (rainy/warm and dry/cold). The aim of this study was to evaluate the effect of these climatic changes on physical, chemical and biological variables in the dynamic of this community. The highest mean density of total protozoans occurred in the rainy/warm season (5683.2 ind L-1), while the lowest was in the dry/cold (2016.0 ind L-1). Considering the seasonal variations, the protozoan groups that are truly planktonic, such as the oligotrichs (Spirotrichea), predominated in the dry season, whereas during the rainy season, due to the material input and resuspension of sediment, sessile protozoans of the Peritrichia group were the most important ones. The dominant protozoans were Urotricha globosa, Cothurnia annulata, Pseudodifflugia sp. and Halteria grandinella. The highest densities of H. grandinella were associated with more oxygenated and transparent water conditions, while the highest densities of C. annulata occurred in sites with high turbidity, pH and trophic state index (TSI). The study demonstrated that density and composition of protozooplanktonic species and groups of the reservoir suffered seasonal variation due to the environmental variables (mainly temperature, turbidity, water transparency, dissolved oxygen and TSI) and the biological variables (e.g. morphological characteristics, eating habits and escape strategies from predation of the species).

  7. Responses of Picea mariana to elevated CO2 concentration during growth, cold hardening and dehardening : phenology, cold tolerance, photosynthesis and growth

    International Nuclear Information System (INIS)

    Bigras, F.J.

    2006-01-01

    Although elevated carbon dioxide (CO 2 ) can promote growth in seedlings, CO 2 may adversely affect bud phenology and cold tolerance. In this study, seedlings from a northern and southern provenance of black spruce were exposed to 37 and 71 Pa of CO 2 during growth, cold hardening and dehardening in a greenhouse. The aim of the study was to assess the photosynthetic response and its impact on growth of black spruce during fall, winter and spring in the context of anticipated climate change. The effects of elevated CO 2 on nonstructural sugars, chlorophyll and nitrogen (N) concentrations were also investigated. Bud set occurred earlier in seedlings with elevated CO 2 than in ambient CO 2 . An increase in seedling cold tolerance in early fall was related to early bud set in elevated CO 2 . Photochemical efficiency, effective quantum yield, photochemical quenching, light-saturated rate of carboxylation, and electron transport decreased during hardening and recovered during dehardening. Elevated CO 2 reduced gene expression of the small subunit of Rubisco and decreased chlorophyll a/chlorophyll b ratio and N concentration in needles, confirming down-regulation of photosynthesis. Total seedling dry mass was higher in elevated CO 2 than in ambient CO 2 at the end of the growing season. Results suggested that differences in photosynthetic rate observed during fall, winter and spring accounted for the inter-annual variations in carbon assimilation of the seedlings. It was concluded that the variations need to be considered in carbon budget studies. It was concluded that total dry mass was 38 per cent higher in seedlings growing in elevated CO 2 at the end of the growing season. 84 refs., 2 tabs., 9 figs

  8. Overwintering strategy and mechanisms of cold tolerance in the codling moth (Cydia pomonella.

    Directory of Open Access Journals (Sweden)

    Jan Rozsypal

    Full Text Available BACKGROUND: The codling moth (Cydia pomonella is a major insect pest of apples worldwide. Fully grown last instar larvae overwinter in diapause state. Their overwintering strategies and physiological principles of cold tolerance have been insufficiently studied. No elaborate analysis of overwintering physiology is available for European populations. PRINCIPAL FINDINGS: We observed that codling moth larvae of a Central European population prefer to overwinter in the microhabitat of litter layer near the base of trees. Reliance on extensive supercooling, or freeze-avoidance, appears as their major strategy for survival of the winter cold. The supercooling point decreases from approximately -15.3 °C during summer to -26.3 °C during winter. Seasonal extension of supercooling capacity is assisted by partial dehydration, increasing osmolality of body fluids, and the accumulation of a complex mixture of winter specific metabolites. Glycogen and glutamine reserves are depleted, while fructose, alanine and some other sugars, polyols and free amino acids are accumulated during winter. The concentrations of trehalose and proline remain high and relatively constant throughout the season, and may contribute to the stabilization of proteins and membranes at subzero temperatures. In addition to supercooling, overwintering larvae acquire considerable capacity to survive at subzero temperatures, down to -15 °C, even in partially frozen state. CONCLUSION: Our detailed laboratory analysis of cold tolerance, and whole-winter survival assays in semi-natural conditions, suggest that the average winter cold does not represent a major threat for codling moth populations. More than 83% of larvae survived over winter in the field and pupated in spring irrespective of the overwintering microhabitat (cold-exposed tree trunk or temperature-buffered litter layer.

  9. Cool-season precipitation in the southwestern USA since AD 1000: comparison of linear and nonlinear techniques for reconstruction

    Science.gov (United States)

    Ni, Fenbiao; Cavazos, Tereza; Hughes, Malcolm K.; Comrie, Andrew C.; Funkhouser, Gary

    2002-11-01

    A 1000 year reconstruction of cool-season (November-April) precipitation was developed for each climate division in Arizona and New Mexico from a network of 19 tree-ring chronologies in the southwestern USA. Linear regression (LR) and artificial neural network (NN) models were used to identify the cool-season precipitation signal in tree rings. Using 1931-88 records, the stepwise LR model was cross-validated with a leave-one-out procedure and the NN was validated with a bootstrap technique. The final models were also independently validated using the 1896-1930 precipitation data. In most of the climate divisions, both techniques can successfully reconstruct dry and normal years, and the NN seems to capture large precipitation events and more variability better than the LR. In the 1000 year reconstructions the NN also produces more distinctive wet events and more variability, whereas the LR produces more distinctive dry events. The 1000 year reconstructed precipitation from the two models shows several sustained dry and wet periods comparable to the 1950s drought (e.g. 16th century mega drought) and to the post-1976 wet period (e.g. 1330s, 1610s). The impact of extreme periods on the environment may be stronger during sudden reversals from dry to wet, which were not uncommon throughout the millennium, such as the 1610s wet interval that followed the 16th century mega drought. The instrumental records suggest that strong dry to wet precipitation reversals in the past 1000 years might be linked to strong shifts from cold to warm El Niño-southern oscillation events and from a negative to positive Pacific decadal oscillation.

  10. Temperature dependent RNA metabolism in Xylella fastidiosa during cold stress and grapevine infection

    Science.gov (United States)

    Re-occurrence of Pierce’s disease of grapes, caused by Xylella fastidiosa, is known to be influenced by environmental factors, particularly cold temperatures during overwintering. Grapevines in colder regions are often cured of X. fastidiosa infection over the winter season, depending on cultivar, t...

  11. Application of Seasonal Trend Loess to GPS data in Cascadia

    Science.gov (United States)

    Bal, A.; Bartlow, N. M.

    2016-12-01

    Plate Boundary Observatory GPS stations provide crucial data for the study of slow slip events and volcanic hazards in the Cascadia region. However, these GPS stations also record seasonal changes in deformation caused by hydrologic, atmospheric, and other seasonal loading. Removing these signals is necessary for accurately modeling the tectonic sources of deformation. Traditionally, seasonal trends in data been accounted for by fitting and removing sine curves from the data. However, not all seasonal trends follow a sinusoidal shape. Seasonal Trend Loess, or STL, is a filtering procedure for a decomposing a time series into trend, seasonal, and remainder components (Cleveland et. al, Journal of Official Statistics, 1990). STL has a simple design that consists of a sequence of applications of the loess smoother which allows for fast computation of large amounts of trend and seasonal smoothing. STL allows for non-sinusoidal shapes in seasonal deformation signals, and allows for evolution of seasonal signals over time. We applied Seasonal Trend Loess to GPS data from the Cascadia region. We compared our results to a traditional sine wave fit for seasonal removal at selected stations, including stations with slow slip event and volcanic signals. We hope that the STL method may be able to more accurately differentiate seasonal and tectonic deformation signals.

  12. Latitudinal range influences the seasonal variation in the foraging behavior of marine top predators.

    Directory of Open Access Journals (Sweden)

    Stella Villegas-Amtmann

    Full Text Available Non-migratory resident species should be capable of modifying their foraging behavior to accommodate changes in prey abundance and availability associated with a changing environment. Populations that are better adapted to change will have higher foraging success and greater potential for survival in the face of climate change. We studied two species of resident central place foragers from temperate and equatorial regions with differing population trends and prey availability associated to season, the California sea lion (Zalophus californianus (CSL whose population is increasing and the endangered Galapagos sea lion (Zalophus wollebaeki (GSL whose population is declining. To determine their response to environmental change, we studied and compared their diving behavior using time-depth recorders and satellite location tags and their diet by measuring C and N isotope ratios during a warm and a cold season. Based on latitudinal differences in oceanographic productivity, we hypothesized that the seasonal variation in foraging behavior would differ for these two species. CSL exhibited greater seasonal variability in their foraging behavior as seen in changes to their diving behavior, foraging areas and diet between seasons. Conversely, GSL did not change their diving behavior between seasons, presenting three foraging strategies (shallow, deep and bottom divers during both. GSL exhibited greater dive and foraging effort than CSL. We suggest that during the warm and less productive season a greater range of foraging behaviors in CSL was associated with greater competition for prey, which relaxed during the cold season when resource availability was greater. GSL foraging specialization suggests that resources are limited throughout the year due to lower primary production and lower seasonal variation in productivity compared to CSL. These latitudinal differences influence their foraging success, pup survival and population growth reflected in

  13. Freezing tolerance of wheat cultivars at the early growing season ...

    African Journals Online (AJOL)

    Cold stress is a worldwide abiotic stress in temperate regions that affects plant development and yield of winter wheat (Triticum aestivum L.) cultivars and other winter crops. This study was conducted to evaluate the effect of freezing stress at the early growing season on survival and also the relationship between resistances ...

  14. Impact of inter-seasonal solar variability on the association of lower troposphere and cold point tropopause in the tropics: Observations using RO data from COSMIC

    Science.gov (United States)

    Kumar, V.; Dhaka, S. K.; Ho, Shu-Peng; Singh, Narendra; Singh, Vir; Reddy, K. K.; Chun, H.-Y.

    2017-12-01

    Association of lower tropospheric variations with the cold point tropopause (CPT) is examined on inter-seasonal basis over the tropical region (30°N-30°S) during 2007-2010 using COSMIC/FORMOST-3 Radio Occultation (RO) data. Temperature analyses for this association are shown over different regions of the globe having contrast topography namely over Western Pacific sector, Indian sector, and African sector. Correlation coefficient (r), taken as a measurement of association, show specific longitudinal differences between the lower troposphere (from 1 km to 5 km height) and the CPT. The northern and southern hemispheres show contrast coupling of temperature variation between lower tropospheric region and the CPT. Land and ocean effects are found to contribute in a different way to the correlation coefficient. Analyses show symmetrical structure of 'r' on both sides of the equator over the African region, as data include mostly land region on both side of equator. Data represent positive correlation (r 0.5) over 15°-20° latitudes on either side of the equator over the African region, suggesting strong hold of the inter-seasonal variation of solar diabatic heating influence over the tropic of Cancer and tropic of Capricorn. On the other hand, there is a contrast behaviour over the Indian region, 'r' is nearly negative ( - 1.0) each year in the southern hemisphere (SH) and positive ( 0.4) in the northern hemisphere (NH) with a maxima near tropic of Cancer. Western Pacific region is found to display a linear increase in 'r' from negative ( - 1.0) in SH to positive ( 0.8) in NH. In general, 'r' (positive) maximizes over the land region around 15°-20° latitudes, suggesting a control of in phase inter-seasonal solar heating on the coupling of boundary layer/lower troposphere and CPT region, whereas it turns negative over water body. Analyses suggest that variabilities in CPT over different regions of globe show significant inter-seasonal association with the lower

  15. Seek and you shall find--but then what do you do? Cold agglutinins in cardiopulmonary bypass and a single-center experience with cold agglutinin screening before cardiac surgery.

    Science.gov (United States)

    Jain, Michael D; Cabrerizo-Sanchez, Rosa; Karkouti, Keyvan; Yau, Terrence; Pendergrast, Jacob M; Cserti-Gazdewich, Christine M

    2013-04-01

    Cardiopulmonary bypass (CPB) during cardiac surgery can involve deliberate hypothermia of the systemic (22-36 °C) and coronary circulations (as low as 8-12 °C). Adverse sequelae of cold-active antibodies have been feared and reported under such conditions, and some centers thus elect to screen for cold agglutinins before CPB. We reviewed the literature on cold agglutinins in cardiac surgery and described the yields and effects of cold agglutinin screening (CAS) in 14,900 cardiac surgery patients undergoing CPB over 8 years at a single institution. Cold agglutinin screening was positive in 47 cases (0.3%), at an annual testing cost of $17,000 CAD. The response of the surgical team to the preoperative discovery of a cold agglutinin was variable, with CPB modified to avoid hypothermia in approximately one-third of cases. In patients discovered to have a positive CAS, postoperative intensive care unit and hospital length of stay were marginally increased (54.6 vs. 42.8 hours, P = .02; 7 [6-14] vs. 7 [5-9] days, P = .04). However, the composite of mortality or severe morbidity (stroke, myocardial infarction, dialysis, low output syndrome, sepsis, and deep vein thrombosis) was not significantly different (14.9% vs. 9.2%, P = .2). Antibody verification found that only 43% of positive CAS patients had true cold agglutinins (20 patients). Furthermore, the rate of adverse events was low in both CAS-positive and true-positive cold agglutinin patients undergoing CPB and cardiac surgery. Finally, modification of CPB to attenuate hypothermia did not decrease adverse events. Based upon historical and local data, preclinical CAS is cost-substantial and nonspecific. Cold agglutinin screening does not promote an algorithm of care that meaningfully improves patient CPB outcomes. Copyright © 2013 Elsevier Inc. All rights reserved.

  16. Seasonal and inter-annual temperature variability in the bottom waters over the Black Sea shelf

    Science.gov (United States)

    Shapiro, G. I.; Wobus, F.; Aleynik, D. L.

    2011-02-01

    convection events is well preserved over the following months in the deep sea, the signal of winter cooling in the Bottom Shelf Waters significantly reduces during the warm season. The time series of temperature in the BSW is highly correlated with the temperature of Cold Intermediate Waters in the deep sea thus indicating that the isopycnal exchanges with the deep sea are more important for inter-annual/inter-decadal variability of the BSW on the Western Black Sea shelf than winter convection on the shelf itself.

  17. Fructan accumulation and transcription of candidate genes during cold acclimation in three varieties of Poa pratensis

    DEFF Research Database (Denmark)

    Rao, R Shyama Prasad; Andersen, Jeppe Reitan; Dionisio, Giuseppe

    2011-01-01

    Poa pratensis, a type species for the grass family (Poaceae), is an important cool season grass that accumulates fructans as a polysaccharide reserve. We studied fructan contents and expression of candidate fructan metabolism genes during cold acclimation in three varieties of P. pratensis adapted...... to different environments: Northern Norway, Denmark, and the Netherlands. Fructan content increased significantly during cold acclimation and varieties showed significant differences in the level of fructan accumulation. cDNA sequences of putative fructosyltransferase (FT), fructan exohydrolase (FEH), and cold...... acclimation protein (CAP) genes were identified and cloned. In agreement with a function in fructan biosynthesis, transcription of a putative sucrose:fructan 6-fructosyltransferase (Pp6-SFT) gene was induced during cold acclimation and fructan accumulation in all three P. pratensis varieties. Transcription...

  18. Seasonal and interannual variability of the eastern boundary circulation and hydrography off Angola

    Science.gov (United States)

    Tchipalanga, Pedro; Macuéria, Marissa; Dengler, Marcus; Ostrowski, Marek; Kopte, Robert; Brandt, Peter

    2016-04-01

    Coastal countries of southwest Africa strongly depend upon their ocean: societal development, fisheries, and tourism face important changes associated with climate variability and global change. As an example, Angolan fisheries are currently reporting reduced catches that may be associated to variability of the eastern boundary circulation and water masses along the Angolan continental margin. In an effort to enhance understanding of the seasonal and interannual variability of the boundary circulation and thermocline water masses and their relation to warm and cold events in South East Atlantic, existing in-situ observations from a multi-cruise program were analyzed. Repeated hydrography and ship-board ADCP measurements from the EAF - Nansen Project collected during the Austral summer and winter period between 1995 and 2014 are used. From the ship-board velocity measurements, the average eastern boundary circulation at 6°S, 9°S, 12°S, 15°S and 17°S is presented for the summer and winter period. CTD data collected during the 24 cruises along the Angolan continental margin exhibit elevated interannual variability of heat and salt content in the upper thermocline between 50 and 150m depth. Warm and cold anomalies in the upper thermocline are strongly correlated to the Angola-Benguela area index and precede the respective sea surface temperature signal. The known warm events in 2001 and 2011 are well represented in the subsurface data. This suggests that thermocline heat anomalies serve as a preconditioning for the occurrences of Benguela Niños/Niñas. The processes responsible for the interannual variability of thermocline heat and salt contend are discussed.

  19. Time To Talk About Natural Products for the Flu and Colds: What Does the Science Say?

    Science.gov (United States)

    ... What Does the Science Say? Share: It’s that time of year again— cold and flu season. Each ... effects of taking probiotics for long periods of time. Most people may be able to use probiotics ...

  20. Deciphering the Metabolic Changes Associated with Diapause Syndrome and Cold Acclimation in the Two-Spotted Spider Mite Tetranychus urticae

    Science.gov (United States)

    Khodayari, Samira; Moharramipour, Saeid; Larvor, Vanessa; Hidalgo, Kévin; Renault, David

    2013-01-01

    Diapause is a common feature in several arthropod species that are subject to unfavorable growing seasons. The range of environmental cues that trigger the onset and termination of diapause, in addition to associated hormonal, biochemical, and molecular changes, have been studied extensively in recent years; however, such information is only available for a few insect species. Diapause and cold hardening usually occur together in overwintering arthropods, and can be characterized by recording changes to the wealth of molecules present in the tissue, hemolymph, or whole body of organisms. Recent technological advances, such as high throughput screening and quantification of metabolites via chromatographic analyses, are able to identify such molecules. In the present work, we examined the survival ability of diapausing and non-diapausing females of the two-spotted spider mite, Tetranychus urticae, in the presence (0 or 5°C) or absence of cold acclimation. Furthermore, we examined the metabolic fingerprints of these specimens via gas chromatography-mass spectrophotometry (GC-MS). Partial Least Square Discriminant Analysis (PLS-DA) of metabolites revealed that major metabolic variations were related to diapause, indicating in a clear cut-off between diapausing and non-diapausing females, regardless of acclimation state. Signs of metabolic depression were evident in diapausing females, with most amino acids and TCA cycle intermediates being significantly reduced. Out of the 40 accurately quantified metabolites, seven metabolites remained elevated or were accumulated in diapausing mites, i.e. cadaverine, gluconolactone, glucose, inositol, maltose, mannitol and sorbitol. The capacity to accumulate winter polyols during cold-acclimation was restricted to diapausing females. We conclude that the induction of increased cold hardiness in this species is associated with the diapause syndrome, rather than being a direct effect of low temperature. Our results provide novel

  1. Climatology of extreme daily precipitation in Colorado and its diverse spatial and seasonal variability

    Science.gov (United States)

    Mahoney, Kelly M.; Ralph, F. Martin; Walter, Klaus; Doesken, Nolan; Dettinger, Michael; Gottas, Daniel; Coleman, Timothy; White, Allen

    2015-01-01

    The climatology of Colorado’s historical extreme precipitation events shows a remarkable degree of seasonal and regional variability. Analysis of the largest historical daily precipitation totals at COOP stations across Colorado by season indicates that the largest recorded daily precipitation totals have ranged from less than 60 mm day−1 in some areas to more than 250 mm day−1 in others. East of the Continental Divide, winter events are rarely among the top 10 events at a given site, but spring events dominate in and near the foothills; summer events are most common across the lower-elevation eastern plains, while fall events are most typical for the lower elevations west of the Divide. The seasonal signal in Colorado’s central mountains is complex; high-elevation intense precipitation events have occurred in all months of the year, including summer, when precipitation is more likely to be liquid (as opposed to snow), which poses more of an instantaneous flood risk. Notably, the historic Colorado Front Range daily rainfall totals that contributed to the damaging floods in September 2013 occurred outside of that region’s typical season for most extreme precipitation (spring–summer). That event and many others highlight the fact that extreme precipitation in Colorado has occurred historically during all seasons and at all elevations, emphasizing a year-round statewide risk.

  2. Cold episodes in the Peruvian Central Andes: Composites, Types, and their Impacts over South America (1958-2014)

    Science.gov (United States)

    Sulca, J. C.; Vuille, M. F.; Roundy, P. E.; Trasmonte, G.; Silva, Y.; Takahashi, K.

    2015-12-01

    The Mantaro basin (MB) is located in the central Peruvian Andes. Occasionally, cold episodes are observed during austral summer (January-March), that strongly damage crops. However, little is known about the causes and impacts of such cold episodes. The main goal of this study is thus to characterize cold episodes in the MB and assess their large-scale circulation and teleconnections over South America (SA) during austral summer. To identify cold events in the MB daily minimum temperature (Tmin) for the period 1958-2014 from Huayao station, located within the MB was used. A cold episode is defined when daily minimum temperature drops below its 10-percentile for at least one day. Additionally, to study the sensitivity between physical mechanisms associated with cold episodes and temperature, cold episodes are classified in three groups: Weak cold episodes (7.5 ≤ Tmin ≤ 10 percentile), strong cold episodes (Tmin ≤ 2.5 percentile), but excluding the 9 coldest events (Tmin ≤ 0 ͦ C), henceforth referred to as extraordinary cold episodes. Several gridded reanalysis were used to characterize the large-scale circulation, cloud cover and rainfall over SA associated with these events. Weak and strong cold episodes in the MB are mainly associated with a weakening of the Bolivian High-Nordeste Low system by tropical-extratropical interactions. Both types of cold episodes are associated with westerly wind anomalies at mid- and upper-tropospheric levels aloft the Peruvian Central Andes, which inhibit the influx of humid air masses from the lowlands to the east and hence limit the development of cloud cover (e.g., positive OLR anomalies over MB). The resulting clear sky conditions cause nighttime temperatures to drop, leading to cold extremes below 10-percentile. Simultaneously, northeastern Brazil (NEB) registers negative OLR anomalies, strong convection and enhanced cloud cover because displacement of the South Atlantic Convergence Zone (SACZ) toward the northeast of

  3. Evaluation of cool season precipitation event characteristics over the Northeast US in a suite of downscaled climate model hindcasts

    Science.gov (United States)

    Loikith, Paul C.; Waliser, Duane E.; Kim, Jinwon; Ferraro, Robert

    2017-08-01

    Cool season precipitation event characteristics are evaluated across a suite of downscaled climate models over the northeastern US. Downscaled hindcast simulations are produced by dynamically downscaling the Modern-Era Retrospective Analysis for Research and Applications version 2 (MERRA2) using the National Aeronautics and Space Administration (NASA)-Unified Weather Research and Forecasting (WRF) regional climate model (RCM) and the Goddard Earth Observing System Model, Version 5 (GEOS-5) global climate model. NU-WRF RCM simulations are produced at 24, 12, and 4-km horizontal resolutions using a range of spectral nudging schemes while the MERRA2 global downscaled run is provided at 12.5-km. All model runs are evaluated using four metrics designed to capture key features of precipitation events: event frequency, event intensity, even total, and event duration. Overall, the downscaling approaches result in a reasonable representation of many of the key features of precipitation events over the region, however considerable biases exist in the magnitude of each metric. Based on this evaluation there is no clear indication that higher resolution simulations result in more realistic results in general, however many small-scale features such as orographic enhancement of precipitation are only captured at higher resolutions suggesting some added value over coarser resolution. While the differences between simulations produced using nudging and no nudging are small, there is some improvement in model fidelity when nudging is introduced, especially at a cutoff wavelength of 600 km compared to 2000 km. Based on the results of this evaluation, dynamical regional downscaling using NU-WRF results in a more realistic representation of precipitation event climatology than the global downscaling of MERRA2 using GEOS-5.

  4. Observational evidence of seasonality in the timing of loop current eddy separation

    Science.gov (United States)

    Hall, Cody A.; Leben, Robert R.

    2016-12-01

    Observational datasets, reports and analyses over the time period from 1978 through 1992 are reviewed to derive pre-altimetry Loop Current (LC) eddy separation dates. The reanalysis identified 20 separation events in the 15-year record. Separation dates are estimated to be accurate to approximately ± 1.5 months and sufficient to detect statistically significant LC eddy separation seasonality, which was not the case for previously published records because of the misidentification of separation events and their timing. The reanalysis indicates that previously reported LC eddy separation dates, determined for the time period before the advent of continuous altimetric monitoring in the early 1990s, are inaccurate because of extensive reliance on satellite sea surface temperature (SST) imagery. Automated LC tracking techniques are used to derive LC eddy separation dates in three different altimetry-based sea surface height (SSH) datasets over the time period from 1993 through 2012. A total of 28-30 LC eddy separation events were identified in the 20-year record. Variations in the number and dates of eddy separation events are attributed to the different mean sea surfaces and objective-analysis smoothing procedures used to produce the SSH datasets. Significance tests on various altimetry and pre-altimetry/altimetry combined date lists consistently show that the seasonal distribution of separation events is not uniform at the 95% confidence level. Randomization tests further show that the seasonal peak in LC eddy separation events in August and September is highly unlikely to have occurred by chance. The other seasonal peak in February and March is less significant, but possibly indicates two seasons of enhanced probability of eddy separation centered near the spring and fall equinoxes. This is further quantified by objectively dividing the seasonal distribution into two seasons using circular statistical techniques and a k-means clustering algorithm. The estimated

  5. Investigating temperature breaks in the summer fruit export cold chain - a case study

    CSIR Research Space (South Africa)

    Freiboth, HW

    2013-11-01

    Full Text Available There is concern in the South African fruit industry that a large amount of fruit and money is lost every season due to breaks in the fruit export cold chain. The possibility of a large percentage of losses in a significant sector of the economy...

  6. Enzyme activity, hormone concentration in tree shrew (Tupaia belangeri during cold acclimation

    Directory of Open Access Journals (Sweden)

    Lin Zhang

    2012-08-01

    Full Text Available Environmental factors play an important role in the seasonal adaptation of body mass and thermogenesis in wild small mammals. The tree shrew (Tupaia belangeri, is a unique species of small mammals which is origin of island in the Oriental realm. The present study was to test the hypothesis that ambient temperature was a cue to induce adjustments in body mass, energy intake, metabolism, uncoupling protein 1 (UCP1 in brown adipose tissue (BAT, and other biochemical characters of T. belangeri during cold exposure about 21 days. Our data demonstrate that cold acclimation induced a remarkable increase in body mass, a significant increase in energy intake and metabolic rate, and high expression of UCP1 in BAT of T. belangeri. Cold acclimation induced an increase in cytochrome c oxidase (COX and Thyroidhormones (T3/T4. These data supported that T. belangeri increased the body mass and increased energy intake and expenditure under cold acclimation. Increased expression of UCP1 was potentially involved in the regulation of energy metabolism and thermogenic capacity following cold acclimation. And it through changes in enzyme activity and hormone concentration under cold acclimation, and suggested temperature changes play an important role in the regulation of thermogenic capacity in tree shrew.

  7. Changes in cold tolerance due to a 14-day stay in the Canadian Arctic

    Science.gov (United States)

    Livingstone, S. D.; Romet, T.; Keefe, A. A.; Nolan, R. W.

    1996-12-01

    Responses to cold exposure tests both locally and of the whole body were examined in subjects who stayed in the Arctic (average maximum and minimum temperatures -11 and -21° C respectively) for 14 days of skiing and sleeping in tents. These changes were compared to responses in subjects living working in Ottawa, Canada (average max. and min. temperatures -5 and -11° C respectively). The tests were done before the stay in the Arctic (Pre), immediately after the return (Post 1) and approximately 32 days after the return (Post 2). For the whole-body cold exposure each subject, wearing only shorts and lying on a rope mesh cot, was exposed to an ambient temperature of 10° C. There was no consistent response in the changes of metabolic or body temperature to this exposure in either of groups and, in addition, the changes over time were variable. Cold induced vasodilatation (CIVD) was determined by measuring temperature changes in the middle finger of the nondominant hand upon immersion in ice water for 30 min. CIVD was depressed after the Arctic exposure whilst during the Post 2 testing, although variable, did not return to the Pre values; the responses of the control group were similar. These results indicate that normal seasonal changes may be as important in adaptation as a stay in the Arctic. Caution is advised in the separation of seasonal effects when examining the changes in adaptation after exposure to a cold environment.

  8. Transcriptome response mediated by cold stress in Lotus japonicus

    Directory of Open Access Journals (Sweden)

    Pablo Ignacio Calzadilla

    2016-03-01

    Full Text Available Members of the Lotus genus are important as agricultural forage sources under marginal environmental conditions given their high nutritional value and tolerance of various abiotic stresses. However, their dry matter production is drastically reduced in cooler seasons, while their response to such conditions is not well studied. This paper analyzes cold acclimation of the genus by studying Lotus japonicus over a stress period of 24 h. High-throughput RNA sequencing was used to identify and classify 1077 differentially expressed genes, of which 713 were up-regulated and 364 were down-regulated. Up-regulated genes were principally related to lipid, cell wall, phenylpropanoid, sugar, and proline regulation, while down-regulated genes affected the photosynthetic process and chloroplast development. Together, a total of 41 cold-inducible transcription factors were identified, including members of the AP2/ERF, NAC, MYB, and WRKY families; two of them were described as putative novel transcription factors. Finally, DREB1/CBFs were described with respect to their cold stress expression profiles. This is the first transcriptome profiling of the model legume L. japonicus under cold stress. Data obtained may be useful in identifying candidate genes for breeding modified species of forage legumes that more readily acclimate to low temperatures

  9. ABA Is Involved in Regulation of Cold Stress Response in Bermudagrass

    Directory of Open Access Journals (Sweden)

    Xuebing Huang

    2017-10-01

    Full Text Available As a representative warm-season grass, Bermudagrass [Cynodon dactylon (L. Pers.] is widely used in turf systems. However, low temperature remarkably limits its growth and distribution. ABA is a crucial phytohormone that has been reported to regulate much important physiological and biochemical processes in plants under abiotic stress. Therefore, the objective of this study was to figure out the effects of ABA on the cold-sensitive (S and cold-resistant (R Bermudagrass genotypes response to cold stress. In this study, the plants were treated with 100 μM ABA solution and exposed to 4°C temperature. After 7 days of cold treatment, the electrolyte leakage (EL, malonaldehyde (MDA and H2O2 content were significantly increased in both genotypes compared with control condition, and these values were higher in R genotype than those of S genotype, respectively. By contrast, exogenous ABA application decreased the electrolyte leakage (EL, MDA and H2O2 content in both genotypes compared with those plants without ABA treatment under cold treatment condition. In addition, exogenous ABA application increased the levels of chlorophyll a fluorescence transient curve for both genotypes, and it was higher in R genotype than that of S genotype. Analysis of photosynthetic fluorescence parameters revealed that ABA treatment improved the performance of photosystem II under cold condition, particularly for the R genotype. Moreover, cold stress significantly increased δ13C values for both genotypes, while it was alleviated by exogenous ABA. Additionally, exogenous ABA application altered the expression of ABA- or cold related genes, including ABF1, CBF1, and LEA. In summary, exogenous ABA application enhanced cold resistance of both genotypes by maintaining cell membrane stability, improving the process of photosystem II, increasing carbon isotopic fractionation under cold stress, and more prominently in R genotype compared with S genotype.

  10. Effect assessment of Future Climate Change on Water Resource and Snow Quality in cold snowy regions in Japan

    Science.gov (United States)

    Taniguchi, Y.; Nakatsugawa, M.; Kudo, K.

    2017-12-01

    It is predicted that the effects of global warming on everyday life will be clearly seen in cold, snowy regions such as Hokkaido. In relation to climate change, there is the concern that the warmer climate will affect not only water resources, but also local economies, in snowy areas, when air temperature increases and snowfall decreases become more marked in the future. Communities whose economies are greatly dependent on snow as a tourism resource, such as for winter sports and snow events, will lose large numbers of visitors because of the shortened winter season. This study was done as a basic study to provide basic ideas for planning adaptation strategies against climate change based on the local characteristics of a cold, snowy region. By taking dam catchment basins in Hokkaido as the subject areas and by using the climate change prediction data that correspond to IPCCAR5, the local-level influence of future climate change on snowfall and snow quality in relation to water resources and winter sports was quantitatively assessed. The water budget was examined for a dam catchment basin in Hokkaido under the present climate (September 1984 to August 2004) and under the future climate (September 2080 to August 2100) by using rainfall, snowfall and evapotranspiration estimated by the LoHAS heat and water balance analysis model.The examination found that, under the future climate, the net annual precipitation will decrease by up to 200 mm because of decreases in precipitation and in runoff height that will result from increased evapotranspiration. The predicted decrease in annual hydro potential of snowfall was considered to greatly affect the dam reservoir operation during the snowmelt season. The snow quality analysis by SNOWPACK revealed that the future snow would become granular earlier than it does at present. Most skiers' snow preferences, from best to worst, are light dry snow (i.e., fresh snow), lightly compacted snow, compacted snow and, finally, granular

  11. Positron Plasma Control Techniques Applied to Studies of Cold Antihydrogen

    CERN Document Server

    Funakoshi, Ryo

    2003-01-01

    In the year 2002, two experiments at CERN succeeded in producing cold antihydrogen atoms, first ATHENA and subsequently ATRAP. Following on these results, it is now feasible to use antihydrogen to study the properties of antimatter. In the ATHENA experiment, the cold antihydrogen atoms are produced by mixing large amounts of antiprotons and positrons in a nested Penning trap. The complicated behaviors of the charged particles are controlled and monitored by plasma manipulation techniques. The antihydrogen events are studied using position sensitive detectors and the evidence of production of antihydrogen atoms is separated out with the help of analysis software. This thesis covers the first production of cold antihydrogen in the first section as well as the further studies of cold antihydrogen performed by using the plasma control techniques in the second section.

  12. Small mammal use of native warm-season and non-native cool-season grass forage fields

    Science.gov (United States)

    Ryan L Klimstra,; Christopher E Moorman,; Converse, Sarah J.; Royle, J. Andrew; Craig A Harper,

    2015-01-01

    Recent emphasis has been put on establishing native warm-season grasses for forage production because it is thought native warm-season grasses provide higher quality wildlife habitat than do non-native cool-season grasses. However, it is not clear whether native warm-season grass fields provide better resources for small mammals than currently are available in non-native cool-season grass forage production fields. We developed a hierarchical spatially explicit capture-recapture model to compare abundance of hispid cotton rats (Sigmodon hispidus), white-footed mice (Peromyscus leucopus), and house mice (Mus musculus) among 4 hayed non-native cool-season grass fields, 4 hayed native warm-season grass fields, and 4 native warm-season grass-forb ("wildlife") fields managed for wildlife during 2 summer trapping periods in 2009 and 2010 of the western piedmont of North Carolina, USA. Cotton rat abundance estimates were greater in wildlife fields than in native warm-season grass and non-native cool-season grass fields and greater in native warm-season grass fields than in non-native cool-season grass fields. Abundances of white-footed mouse and house mouse populations were lower in wildlife fields than in native warm-season grass and non-native cool-season grass fields, but the abundances were not different between the native warm-season grass and non-native cool-season grass fields. Lack of cover following haying in non-native cool-season grass and native warm-season grass fields likely was the key factor limiting small mammal abundance, especially cotton rats, in forage fields. Retention of vegetation structure in managed forage production systems, either by alternately resting cool-season and warm-season grass forage fields or by leaving unharvested field borders, should provide refugia for small mammals during haying events.

  13. Exploring the Intersection of Beliefs toward Outdoor Play and Cold Weather among Northeast Minnesota's Formal Education and Non-Formal EE Communities

    Science.gov (United States)

    Hughes, Amy Christine; Zak, Kevin; Ernst, Julie; Meyer, Rebecca

    2017-01-01

    In a notoriously cold-seasoned region, this paper explored how our formal education and non-formal environmental education (EE) gatekeepers of Northeastern Minnesota regard the importance of outdoor play and cold weather for young students. This research study explored the relationship between participant gatekeepers' beliefs of the benefits…

  14. Lightning Location System Data from Wind Power Plants Compared to Meteorological Conditions of Warm- and Cold Thunderstorm Events

    DEFF Research Database (Denmark)

    Vogel, Stephan; Lopez, Javier; Garolera, Anna Candela

    2016-01-01

    of topography, height above mean sea level (AMSL), and average ground flash density. For three sites, the most severe lightning events have been identified during the warm and cold months whereas the other two locations exhibit severe lightning detections mainly during the warm months. In this work severity......Five years of Lightning Location System (LLS) data from five different wind turbine sites in Europe are analysed. The sites are located in Croatia, Italy, Spain, France and one offshore wind power plant in the North sea. Each location exhibits individual characteristic properties in terms...... of such an episode can vary from tens of minutes to several hours in the case of new storms being continuously developed in the same area. The distance of the charge separating -10◦ C and the ground is usually larger than 3000 meters. This analyse provides information about the different thunderstorm types which...

  15. [Spatial and temporal variations of hydrological characteristic on the landscape zone scale in alpine cold region].

    Science.gov (United States)

    Yang, Yong-Gang; Hu, Jin-Fei; Xiao, Hong-Lang; Zou, Song-Bing; Yin, Zhen-Liang

    2013-10-01

    There are few studies on the hydrological characteristics on the landscape zone scale in alpine cold region at present. This paper aimed to identify the spatial and temporal variations in the origin and composition of the runoff, and to reveal the hydrological characteristics in each zone, based on the isotopic analysis of glacier, snow, frozen soil, groundwater, etc. The results showed that during the wet season, heavy precipitation and high temperature in the Mafengou River basin caused secondary evaporation which led to isotope fractionation effects. Therefore, the isotope values remained high. Temperature effects were significant. During the dry season, the temperature was low. Precipitation was in the solid state during the cold season and the evaporation was weak. Water vapor came from the evaporation of local water bodies. Therefore, less secondary evaporation and water vapor exchange occurred, leading to negative values of delta18O and deltaD. delta18O and deltaD values of precipitation and various water bodies exhibited strong seasonal variations. Precipitation exhibited altitude effects, delta18O = -0. 005 2H - 8. 951, deltaD = -0.018 5H - 34. 873. Other water bodies did not show altitude effects in the wet season and dry season, because the runoff was not only recharged by precipitation, but also influenced by the freezing and thawing process of the glacier, snow and frozen soil. The mutual transformation of precipitation, melt water, surface water and groundwater led to variations in isotopic composition. Therefore, homogenization and evaporation effect are the main control factors of isotope variations.

  16. Characterization of road runoff with regard to seasonal variations, particle size distribution and the correlation of fine particles and pollutants.

    Science.gov (United States)

    Hilliges, R; Endres, M; Tiffert, A; Brenner, E; Marks, T

    2017-03-01

    Urban runoff is known to transport a significant pollutant load consisting of e.g. heavy metals, salts and hydrocarbons. Interactions between solid and dissolved compounds, proper understanding of particle size distribution, dissolved pollutant fractions and seasonal variations is crucial for the selection and development of appropriate road runoff treatment devices. Road runoff at an arterial road in Augsburg, Germany, has been studied for 3.5 years. A strong seasonal variation was observed, with increased heavy metal concentrations with doubled and tripled median concentrations for heavy metals during the cold season. Correlation analysis showed that de-icing salt is not the only factor responsible for increased pollutant concentrations in winter. During the cold period, the fraction of dissolved metals was lower compared to the warm season. In road dust, the highest metal concentrations were measured for fine particles. Metals in road runoff were found to show a significant correlation to fine particles SS63 (removal rates.

  17. The role of phytophysiognomies and seasonality on the structure of ground-dwelling anuran (Amphibia) in the Pampa biome, Southern Brazil.

    Science.gov (United States)

    Maragno, Franciéle P; Santos, Tiago G; Cechin, Sonia Z

    2013-09-01

    Considering that habitat use by amphibians is related both with climate and environmental features, we tested the hypothesis that anuran assemblages found in different phytophysiognomies and in different seasons vary in structure. Additionally, we searched for species which can be indicators of habitat and seasons. The study was conducted in the Pampa biome, southern Brazil. Sampling was done through pitfall traps placed in three phytophysiognomies: grassland, ecotone grassland/forest; and forest. The seasonality factor was created by grouping months in warn and cold seasons. Sixteen species were found and the assemblages were influenced both by phytophysiognomies and climatic seasonality. In a paired comparison, the three phytophysiognomies differed in structure of assemblage from each other. Physalaemus henselii, P. riograndensis, Pseudopaludicola falcipes and Pseudis minuta were indicators of ecotone. Leptodactylus gracilis and Physalaemus biligonigerus were indicators of grassland. None species was indicator of forest. Most of the species were indicators of warm season: Elachistocleis bicolor, Leptodactylus fuscus, L. gracilis, L. latinasus, L. latrans, L. mystacinus, Physalaemus biligonigerus, P. cuvieri and Pseudis minuta. None species was indicator of cold season. We found that even for species of open areas, as Pampa, heterogeneous phytophysiognomies are important for maintaining abundance and constancy of populations of anuran.

  18. How cold is cold dark matter?

    International Nuclear Information System (INIS)

    Armendariz-Picon, Cristian; Neelakanta, Jayanth T.

    2014-01-01

    If cold dark matter consists of particles, these must be non-interacting and non-relativistic by definition. In most cold dark matter models however, dark matter particles inherit a non-vanishing velocity dispersion from interactions in the early universe, a velocity that redshifts with cosmic expansion but certainly remains non-zero. In this article, we place model-independent constraints on the dark matter temperature to mass ratio, whose square root determines the dark matter velocity dispersion. We only assume that dark matter particles decoupled kinetically while non-relativistic, when galactic scales had not entered the horizon yet, and that their momentum distribution has been Maxwellian since that time. Under these assumptions, using cosmic microwave background and matter power spectrum observations, we place upper limits on the temperature to mass ratio of cold dark matter today (away from collapsed structures). These limits imply that the present cold dark matter velocity dispersion has to be smaller than 54 m/s. Cold dark matter has to be quite cold, indeed

  19. Seasonal Changes in Titan's Meteorology

    Science.gov (United States)

    Turtle, E. P.; DelGenio, A. D.; Barbara, J. M.; Perry, J. E.; Schaller, E. L.; McEwen, A. S.; West, R. A.; Ray, T. L.

    2011-01-01

    The Cassini Imaging Science Subsystem has observed Titan for 1/4 Titan year, and we report here the first evidence of seasonal shifts in preferred locations of tropospheric methane clouds. South \\polar convective cloud activity, common in late southern summer, has become rare. North \\polar and northern mid \\latitude clouds appeared during the approach to the northern spring equinox in August 2009. Recent observations have shown extensive cloud systems at low latitudes. In contrast, southern mid \\latitude and subtropical clouds have appeared sporadically throughout the mission, exhibiting little seasonality to date. These differences in behavior suggest that Titan s clouds, and thus its general circulation, are influenced by both the rapid temperature response of a low \\thermal \\inertia surface and the much longer radiative timescale of Titan s cold thick troposphere. North \\polar clouds are often seen near lakes and seas, suggesting that local increases in methane concentration and/or lifting generated by surface roughness gradients may promote cloud formation. Citation

  20. Seasonal and inter-annual temperature variability in the bottom waters over the western Black Sea shelf

    Directory of Open Access Journals (Sweden)

    G. I. Shapiro

    2011-09-01

    Full Text Available Long-term changes in the state of the Bottom Shelf Water (BSW on the Western shelf of the Black Sea are assessed using analysis of intra-seasonal and inter-annual temperature variations. For the purpose of this study the BSW is defined as such shelf water mass between the seabed and the upper mixed layer (bounded by the σθ = 14.2 isopycnal which has limited ability to mix vertically with oxygen-rich surface waters during the warm season due to formation of a seasonal pycnocline. A long-term time series of temperature anomalies in the BSW is constructed from in-situ observations taken over the 2nd half of the 20th century. The BSW is shown to occupy nearly half of the shelf area during the summer stratification period (May–November.The results reveal a warm phase in the 1960s/70s, followed by a cold phase between 1985 and 1995 and a further warming after 1995. The transition between the warm and cold periods coincides with a regime shift in the Black Sea ecosystem. While it was confirmed that the memory of winter convection is well preserved over the following months in the deep sea, the signal of winter cooling in the BSW significantly reduces during the warm season. The potential of the BSW to ventilate horizontally during the warm season with the deep-sea waters is assessed using isopycnic analysis of temperature variations. It is shown that temperature in the BSW is stronger correlated with the temperature of Cold Intermediate Waters (CIW in the deep sea than with the severity of the previous winters, thus indicating that the isopycnal exchanges with the deep sea are more important for inter-annual/inter-decadal variability of the BSW on the western Black Sea shelf than effects of winter convection on the shelf itself.

  1. Cold Antimatter Plasmas, and Aspirations for Cold Antihydrogen

    Science.gov (United States)

    2002-06-24

    UNCLASSIFIED Defense Technical Information Center Compilation Part Notice ADP012494 TITLE: Cold Antimatter Plasmas, and Aspirations for Cold...part numbers comprise the compilation report: ADP012489 thru ADP012577 UNCLASSIFIED Cold Antimatter Plasmas, and Aspirations for Cold Antihydrogen G...and positrons. The antiprotons come initially from the new Antiproton Decel- erator facility at CERN. Good control of such cold antimatter plasmas is

  2. TrMADS3, a new MADS-box gene, from a perennial species Taihangia rupestris (Rosaceae) is upregulated by cold and experiences seasonal fluctuation in expression level.

    Science.gov (United States)

    Du, Xiaoqiu; Xiao, Qiying; Zhao, Ran; Wu, Feng; Xu, Qijiang; Chong, Kang; Meng, Zheng

    2008-06-01

    In many temperate perennial plants, floral transition is initiated in the first growth season but the development of flower is arrested during the winter to ensure production of mature flowers in the next spring. The molecular mechanisms of the process remain poorly understood with few well-characterized regulatory genes. Here, a MADS-box gene, named as TrMADS3, was isolated from the overwintering inflorescences of Taihangia rupestris, a temperate perennial in the rose family. Phylogenetic analysis reveals that TrMADS3 is more closely related to the homologs of the FLOWERING LOCUS C lineage than to any of the other MIKC-type MADS-box lineages known from Arabidopsis. The TrMADS3 transcripts are extensively distributed in inflorescences, roots, and leaves during the winter. In controlled conditions, the TrMADS3 expression level is upregulated by a chilling exposure for 1 to 2 weeks and remains high for a longer period of time in warm conditions after cold treatment. In situ hybridization reveals that TrMADS3 is predominantly expressed in the vegetative and reproductive meristems. Ectopic expression of TrMADS3 in Arabidopsis promotes seed germination on the media containing relatively high NaCl or mannitol concentrations. These data indicate that TrMADS3 in a perennial species might have its role in both vegetative and reproductive meristems in response to cold.

  3. Alleviation of cold damage to photosystem II and metabolisms by melatonin in Bermudagrass

    Directory of Open Access Journals (Sweden)

    Jibiao eFan

    2015-11-01

    Full Text Available As a typical warm-season grass, Bermudagrass [Cynodon dactylon (L.Pers.] is widely applied in turf systems and animal husbandry. However, cold temperature is a key factor limiting resource utilization for Bermudagrass. Therefore, it is relevant to study the mechanisms by which Burmudagrass responds to cold. Melatonin is a crucial animal and plant hormone that is responsible for plant abiotic stress responses. The objective of this study was to investigate the role of melatonin in cold stress response of Bermudagrass. Wild Bermudagrass pre-treated with 100 μM melatonin was subjected to different cold stress treatments (-5 °C for 8 h with or without cold acclimation. The results showed lower malondialdehyde (MDA and electrolyte leakage (EL values, higher levels of chlorophyll, and greater superoxide dismutase and peroxidase activities after melatonin treatment than those in non-melatonin treatment under cold stress. Analysis of chlorophyll a revealed that the chlorophyll fluorescence transient (OJIP curves were higher after treatment with melatonin than that of non-melatonin treated plants under cold stress. The values of photosynthetic fluorescence parameters increased after treatment with melatonin under cold stress. The analysis of metabolism showed alterations in 46 metabolites in cold-stressed plants after melatonin treatment. Among the measured metabolites, five sugars (arabinose, mannose, glucopyranose, maltose, turanose and one organic acid (propanoic acid were significantly increased. However, valine and threonic acid contents were reduced in melatonin-treated plants. In summary, melatonin maintained cell membrane stability, increased antioxidant enzymes activities, improved the process of photosystem II, and induced alterations in Bermudagrass metabolism under cold stress.

  4. Proteome dynamics of cold-acclimating Rhododendron species contrasting in their freezing tolerance and thermonasty behavior.

    Directory of Open Access Journals (Sweden)

    Jose V Die

    Full Text Available To gain a better understanding of cold acclimation in rhododendron and in woody perennials in general, we used the 2D-DIGE technique to analyze the rhododendron proteome during the seasonal development of freezing tolerance. We selected two species varying in their cold acclimation ability as well as their thermonasty response (folding of leaves in response to low temperature. Proteins were extracted from leaves of non-acclimated (NA and cold acclimated (CA plants of the hardier thermonastic species, R. catawbiense (Cata., and from leaves of cold acclimated plants of the less hardy, non-thermonastic R. ponticum (Pont.. All three protein samples (Cata.NA, Cata.CA, and Pont.CA were labeled with different CyDyes and separated together on a single gel. Triplicate gels were run and protein profiles were compared resulting in the identification of 72 protein spots that consistently had different abundances in at least one pair-wise comparison. From the 72 differential spots, we chose 56 spots to excise and characterize further by mass spectrometry (MS. Changes in the proteome associated with the seasonal development of cold acclimation were identified from the Cata.CA-Cata.NA comparisons. Differentially abundant proteins associated with the acquisition of superior freezing tolerance and with the thermonastic response were identified from the Cata.CA-Pont.CA comparisons. Our results indicate that cold acclimation in rhododendron involves increases in abundance of several proteins related to stress (freezing/desiccation tolerance, energy and carbohydrate metabolism, regulation/signaling, secondary metabolism (possibly involving cell wall remodeling, and permeability of the cell membrane. Cold acclimation also involves decreases in abundance of several proteins involved in photosynthesis. Differences in freezing tolerance between genotypes can probably be attributed to observed differences in levels of proteins involved in these functions. Also

  5. Lightning and severe thunderstorms in event management.

    Science.gov (United States)

    Walsh, Katie M

    2012-01-01

    There are a few national position stands/guidelines that address environmental conditions in athletics, yet they do not govern all outdoor sports. Extreme heat and cold, lightning, and severe wind can all be fatal, yet the majority of outdoor sports have no published guidelines addressing these conditions in relation to activity. Available research on extreme heat and cold conditions in athletics provides prevention strategies, to include acclimatization. Lightning and severe wind are two environmental conditions to which humans cannot accommodate, and they both can be deadly. There are strong positions on extreme heat/cold and lightning safety in athletics, but none affiliated with severe winds. Medical personnel involved in planning large outdoor sporting events must know of the presence of nationally published weather-related documents and apply them to their event. In addition, research needs to be expanded in the realm of establishing guidelines for safety to participants and spectators in severe wind conditions.

  6. Assessing cold chain status in a metro city of India: an intervention study.

    Science.gov (United States)

    Mallik, S; Mandal, P K; Chatterjee, C; Ghosh, P; Manna, N; Chakrabarty, D; Bagchi, S N; Dasgupta, S

    2011-03-01

    Cold chain maintenance is an essential activity to maintain the potency of vaccines and to prevent adverse events following immunization. One baseline study highlighted the unsatisfactory cold chain status in city of Kolkata in India. To assess the changes which occurred in the cold chain status after the intervention undertaken to improve the status and also to assess the awareness of the cold chain handlers regarding cold chain maintenance. Intervention consisted of reorganization of cold chain points and training of health manpower in Kolkata Municipal area regarding immunization and cold chain following the guidelines as laid by Govt of India. Reevaluation of cold chain status was done at 20 institutions selected by stratified systematic random sampling after the intervention. The results were compared with baseline survey. Significant improvement had been observed in correct placing of cold chain equipment, maintenance of stock security, orderly placing of ice packs, diluents and vaccines inside the equipment, temperature recording and maintenance. But awareness and skill of cold chain handlers regarding basics of cold chain maintenance was not satisfactory. The success of intervention included significant improvement of cold chain status including creation of a designated cold chain handler. The gaps lay in non-availability of non-electrical cold chain equipment and separate cold chain room, policy makers should stress. Cold chain handlers need reorientation training regarding heat & cold sensitive vaccines, preventive maintenance and correct contingency plan.

  7. Hypothermic general cold adaptation induced by local cold acclimation.

    Science.gov (United States)

    Savourey, G; Barnavol, B; Caravel, J P; Feuerstein, C; Bittel, J H

    1996-01-01

    To study relationships between local cold adaptation of the lower limbs and general cold adaptation, eight subjects were submitted both to a cold foot test (CFT, 5 degrees C water immersion, 5 min) and to a whole-body standard cold air test (SCAT, 1 degree C, 2 h, nude at rest) before and after a local cold acclimation (LCA) of the lower limbs effected by repeated cold water immersions. The LCA induced a local cold adaptation confirmed by higher skin temperatures of the lower limbs during CFT and a hypothermic insulative general cold adaptation (decreased rectal temperature and mean skin temperature P adaptation was related to the habituation process confirmed by decreased plasma concentrations of noradrenaline (NA) during LCA (P general cold adaptation was unrelated either to local cold adaptation or to the habituation process, because an increased NA during SCAT after LCA (P syndrome" occurring during LCA.

  8. Burden and Risk Factors for Cold-Related Illness and Death in New York City

    Directory of Open Access Journals (Sweden)

    Kathryn Lane

    2018-03-01

    Full Text Available Exposure to cold weather can cause cold-related illness and death, which are preventable. To understand the current burden, risk factors, and circumstances of exposure for illness and death directly attributed to cold, we examined hospital discharge, death certificate, and medical examiner data during the cold season from 2005 to 2014 in New York City (NYC, the largest city in the United States. On average each year, there were 180 treat-and-release emergency department visits (average annual rate of 21.6 per million and 240 hospital admissions (29.6 per million for cold-related illness, and 15 cold-related deaths (1.8 per million. Seventy-five percent of decedents were exposed outdoors. About half of those exposed outdoors were homeless or suspected to be homeless. Of the 25% of decedents exposed indoors, none had home heat and nearly all were living in single-family or row homes. The majority of deaths and illnesses occurred outside of periods of extreme cold. Unsheltered homeless individuals, people who use substances and become incapacitated outdoors, and older adults with medical and psychiatric conditions without home heat are most at risk. This information can inform public health prevention strategies and interventions.

  9. Window of cold nuclear fusion and biased-pulse electrolysis experiment

    International Nuclear Information System (INIS)

    Takahashi, Akito; Jida, Toshiyuki; Maekawa, Fujio; Sugimoto, Hisashi; Yoshida, Shigeo

    1989-01-01

    Based on the electron screening effect and the excitation of deuteron harmonic oscillators in palladium lattice, theoretical aspects are given to explain the cold fusion phenomena and the possibility of nuclear heating. A narrow window is proposed to meet ≅ 10 watts per cubic centimeter for the nuclear heating, by the hypothetical excitation-screening model. A relatively wide window is feasible to meet a few fusion events per second per cc under the non-stationary conditions of deuteron-charging and discharging. For stationary lattice conditions, the probability of cold fusion is not feasible at all. To confirm the cold fusion phenomena, a heavy water electrolysis experiment was carried out using biased-pulse-electrolytic currents, expecting the enhancement of cold fusion events under charging and discharging of deuterons. For the neutron detection, a cross-checking system between a recoil-proton scintillation detector and a 3 He thermal neutron detector was employed to see coincident time-patterns of neutron emission from an electrolysis cell. To check the energy of emitted neutrons, pulse height spectrum of the recoil-proton detector was monitored. Up to the D-charging time of 300 hr, neutron yields of 1-2 n/s/cc were obtained for time-intervals of 60-200 hr. From the recoil-proton spectra, it was confirmed that 2.45 MeV neutrons by the D(d, n) 3 He fusion branch were emitted. The observed time-patterns of neutron emission suggest the existence of cold fusion under the charging and discharging conditions. (orig.)

  10. Effects of Cross-axis Wind Jet Events on the Northern Red Sea Circulation

    Science.gov (United States)

    Menezes, V. V.; Bower, A. S.; Farrar, J. T.

    2016-12-01

    Despite its small size, the Red Sea has a complex circulation. There are boundary currents in both sides of the basin, a meridional overturning circulation, water mass formation in the northern part and an intense eddy activity. This complex pattern is driven by strong air-sea interactions. The Red Sea has one of the largest evaporation rates of the global oceans (2m/yr), an intricate and seasonally varying wind pattern. The winds blowing over the Northern Rea Sea (NRS, north of 20N) are predominantly southeastward along the main axis all year round; in the southern, they reverse seasonally due to the monsoonal regime. Although the winds are mostly along-axis in the NRS, several works have shown that sometimes during the boreal winter, the winds blow in a cross-axis direction. The westward winds from Saudi Arabia bring relatively cold dry air and dust from the desert, enhancing heat loss and evaporation off the Red Sea. These wind-jet events may contribute to increased eddy activity and are a trigger for water mass formation. Despite that, our knowledge about the cross-axis winds and their effect on NRS circulation is still incipient. In the present work we analyze 10-years of Quikscat scatterometer winds and altimetric sea surface height anomalies, together with 2-yrs of mooring data, to characterize the westward wind jet events and their impacts on the circulation. We show that the cross-axis winds are, indeed, an important component of the wind regime, explaining 11% of wind variability of the NRS (well-described by a 2nd EOF mode). The westward events occur predominantly in the winter, preferentially in January (about 15 events in 10-years) and have a mean duration of 4-5 days, with a maximum of 12 days (north of 22N). There are around 6 events per year, but in 2002-2003 and 2007-2008, twice more events were detected. The westward wind events are found to strongly modify the wind stress curl, causing a distinct positive/negative curl pattern along the main axis

  11. Seasonal variation of marine organic aerosols in the North Pacific Ocean

    Science.gov (United States)

    Fu, P.; Kawamura, K.

    2017-12-01

    Atmospheric aerosols were collected in the marine boundary layer during five marine cruises in the northern Pacific Ocean from October 1996 to July 1997. Organic molecular compositions of the marine aerosols were measured using gas chromatography/mass spectrometry (GC/MS). Higher concentrations of levoglucosan and its isomers, the biomass-burning tracers, were observed in the coastal regions than those in the central north Pacific. Seasonal trends of biomass burning tracers were found to be higher in fall-winter-spring than in summer, suggesting an enhanced influence of continental aerosols to the marine atmosphere during cold seasons when the westerlies prevail. However, the atmospheric levels of secondary organic aerosol (SOA) tracers from the photooxidation of isoprene and monoterpenes were higher in warm seasons than cold seasons, which are in accordance with the enhanced emissions of biogenic volatile organic compounds (BVOCs) in summer. Stable C isotope ratios of total carbon (δ13CTC) in the marine aerosols ranged from -28.5‰ to -23.6‰ (mean -26.4‰), suggesting an important input of terrestrial/continental aerosol particles. Stable N isotope ratios (2.6‰ to 12.9‰, mean 7.1‰) were found to be higher in the coastal regions than those in the open oceans, suggesting an enhanced emission of marine aerosols in the open oceans. The fluorescence properties of the water-soluble organic carbon (WSOC) in the marine aerosols conform the importance of marine emitted organics in the open ocean, especially during the high biological activity periods.

  12. Selecting wool-type fabrics for sensorial comfort in women office clothing for the cold season, using the multi-criteria decision analysis

    Science.gov (United States)

    Harpa, Rodica

    2017-10-01

    This article presents the strategy and the procedure used to achieve the declared goal: fabrics selection, pursuing sensorial comfort of a specific women-clothing item, by using the multi-criteria decision analysis. First, the objective evaluation of seven wool-type woven fabrics, suitable to the quality profile expected for the defined destination, was accomplished. Then, a survey was conducted on a sample of 187 consumers, women aged between 18 to 60 years old, with a background in the textile field, regarding both the preferences manifested in purchasing products, and the importance of various sensory perceptions through handling materials used in clothing products. Finally, the MCDM applied through the implementation of previous accomplished software STAT-ADM, allowed choosing the preferred wool-type fabric in order to get the expected sensorial comfort of women office trousers for the cold season, according to the previously established criteria. This overall approach showed good results in fabrics selection for assuring the sensorial comfort in women’s clothing, by using the multicriteria decision analysis based on a rating scale delivered by customers with knowledge in the textile field, but non-experts in the fabrics hand evaluation topic.

  13. Packhouse to port: Investigating temperature breaks in the South African summer fruit export cold chain

    CSIR Research Space (South Africa)

    Freiboth, H

    2014-10-01

    Full Text Available A large amount of fruit and money is lost every season due to breaks in the South African fruit export cold chain. With food security becoming an ever growing concern, especially in developing countries like South Africa, a high percentage of losses...

  14. The Origin of the "Seasons" in Space Weather

    Science.gov (United States)

    Dikpati, Mausumi; Cally, Paul S.; McIntosh, Scott W.; Heifetz, Eyal

    2017-11-01

    Powerful `space weather' events caused by solar activity pose serious risks to human health, safety, economic activity and national security. Spikes in deaths due to heart attacks, strokes and other diseases occurred during prolonged power outages. Currently it is hard to prepare for and mitigate the impact of space weather because it is impossible to forecast the solar eruptions that can cause these terrestrial events until they are seen on the Sun. However, as recently reported in Nature, eruptive events like coronal mass ejections and solar flares, are organized into quasi-periodic "seasons", which include enhanced bursts of eruptions for several months, followed by quiet periods. We explored the dynamics of sunspot-producing magnetic fields and discovered for the first time that bursty and quiet seasons, manifested in surface magnetic structures, can be caused by quasi-periodic energy-exchange among magnetic fields, Rossby waves and differential rotation of the solar interior shear-layer (called tachocline). Our results for the first time provide a quantitative physical mechanism for forecasting the strength and duration of bursty seasons several months in advance, which can greatly enhance our ability to warn humans about dangerous solar bursts and prevent damage to satellites and power stations from space weather events.

  15. Cold Episodes, Their Precursors and Teleconnections in the Central Peruvian Andes (1958-2009)

    Science.gov (United States)

    Sulca, J. C.; Vuille, M. F.; Trasmonte, G.; Silva, Y.; Takahashi, K.

    2014-12-01

    The Mantaro valley (MV) is located in the central Peruvian Andes. Occasionally, cold episodes are observed during the austral summer (January-March), which strongly damage crops. However, little is known about the causes and impacts of such cold episodes in the MV. The main goal of this study is thus to characterize cold episodes in the MV and assess their large-scale circulation and teleconnections over South America (SA) during austral summer. To identify cold events in the MV daily minimum temperature for the period 1958-2009 from Huayao station, located within the MV was used. We defined a cold episode as the period when daily minimum temperature drops below the 10-percentile for at least one day. Several gridded reanalysis and satellite products were used to characterize the large-scale circulation, cloud cover and rainfall over SA associated with these events for same period. Cold episodes in the MV are associated with positive OLR anomalies, which extend over much of the central Andes, indicating reduced convective cloud cover during these extremes, but also affirm the large-scale nature of these events. At the same time, northeastern Brazil (NEB) registers negative OLR anomalies, strong convective activity and enhanced cloud cover because displacement of the South Atlantic Convergence Zone (SACZ) toward the northeast of its climatologic position. Further, it is associated with a weakening of the Bolivian High - Nordeste Low (BH-NL) system at upper levels, but also influenced by a low-level migratory high-pressure center develops at 30°S, 50°W; propagating from mid- to low latitudes as part of an extratropical Rossby wave train. In conclusion, cold episodes in the MV appear to be caused by radiative cooling associated with reduced cloudiness, rather than cold air advection. The reduced cloud cover in turn results from a robust large-scale pattern of westerly wind anomalies over central Peruvian Andes, inhibiting moisture influx, convective activity and

  16. Response of aboveground carbon balance to long-term, experimental shifts in precipitation seasonality is contingent on plant community type in cold-desert rangelands

    Science.gov (United States)

    Reinhardt, K.; McAbee, K.; Germino, M. J.; Bosworth, A.

    2016-12-01

    Semi-arid rangelands have been identified as potential carbon (C) sinks. However, the degree of net C storage or release in water-limited systems is a function of precipitation amount and timing, as well as plant community composition. In northern latitudes of western North America, climate models predict increases in wintertime precipitation and decreases in summertime precipitation. In theory, this should boost C storage in cold-desert ecosystems that have deep-rooted woody plants due to greater wintertime soil water storage that enhances summertime productivity. However, there are few long-term, manipulative field-based studies investigating how shrub- and grass-dominated rangelands will respond to changing precipitation patterns. We measured aboveground C pools and fluxes at leaf, soil, and ecosystem scales over the 2014 growing season on plots that had supplemental precipitation added in either winter or summer for 21 years, in shrub- and exotic-bunchgrass-dominated plots. We hypothesized that increased winter precipitation would stimulate aboveground C uptake and storage relative to ambient conditions, in our cold-desert-adapted plant species. We further hypothesized that long-term gains in aboveground C storage due to precipitation manipulations would be greater in plots containing shrubs. Our hypotheses were generally supported: ecosystem C uptake and long-term biomass accumulation were greater in winter- and summer-irrigated plots compared to control plots in both vegetation communities. However, substantial increases in aboveground biomass occurred only in winter-irrigated plots that contained shrubs. Our findings suggest that increases in winter precipitation will enhance C storage of this widespread ecosystem, provided that the ecosystems have resisted conversion to exotic grassland.

  17. Cold Stress

    Science.gov (United States)

    ... Publications and Products Programs Contact NIOSH NIOSH COLD STRESS Recommend on Facebook Tweet Share Compartir Workers who ... cold environments may be at risk of cold stress. Extreme cold weather is a dangerous situation that ...

  18. Dynamics of Laboratory Simulated Microbursts

    Science.gov (United States)

    Alahyari, Abbas Alexander

    1995-01-01

    A downburst (or microburst) is an intense, localized downdraft of cold air which reaches the Earth and spreads radially outward after it impinges on the ground. Downdrafts are typically induced by rapid evaporation of moisture or melting of hail. The divergent outflow created by a microburst produces strong winds in opposite directions. The sudden changes in the speed and direction of both horizontal and vertical winds within a microburst can create hazardous conditions for aircraft within 1000 ft of the ground, particularly during takeoff and landing. The objective of this investigation was to obtain detailed measurements within a laboratory -simulated version of this flow. The flow was modeled experimentally by releasing a small volume of heavier fluid into a less dense ambient surrounding. The heavier fluid impinged on a horizontal plate which represented the ground. Indices of refraction of the light and heavy fluid were matched to yield clear photographic images. Particle image velocimetry (PIV) was used to obtain detailed maps of the instantaneous velocity fields within horizontal and vertical cross sections through the flow. Laser-induced fluorescence (LIF) was used to determine the local concentration of heavy fluid within the downburst flow at different times. PIV measurements showed that the leading edge of the falling fluid rolled up into a vortex ring which then impacted on the ground and expanded radially outward. After touchdown, the largest horizontal velocities occurred beneath the vortex ring but also extended over some distance upstream of the vortex core. PIV results showed small vertical velocity gradients in the region below the core of the vortex ring. The effects of parameters such as initial release height and release volume shape were investigated. Using appropriate length and time scales, the measured velocities were scaled to and compared with previously studied atmospheric microbursts. The experimental data generally agree well with

  19. Cold Climate Structural Fire Danger Rating System?

    Directory of Open Access Journals (Sweden)

    Maria-Monika Metallinou

    2018-03-01

    Full Text Available Worldwide, fires kill 300,000 people every year. The fire season is usually recognized to be in the warmer periods of the year. Recent research has, however, demonstrated that the colder season also has major challenges regarding severe fires, especially in inhabited (heated wood-based structures in cold-climate areas. Knowledge about the effect of dry cellulose-based materials on fire development, indoor and outdoor, is a motivation for monitoring possible changes in potential fire behavior and associated fire risk. The effect of wind in spreading fires to neighboring structures points towards using weather forecasts as information on potential fire spread behavior. As modern weather forecasts include temperature and relative humidity predictions, there may already be sufficient information available to develop a structural fire danger rating system. Such a system may include the following steps: (1 Record weather forecasts and actual temperature and relative humidity inside and outside selected structures; (2 Develop a meteorology-data-based model to predict indoor relative humidity levels; (3 Perform controlled drying chamber experiments involving typical hygroscopic fire fuel; (4 Compare the results to the recorded values in selected structures; and (5 Develop the risk model involving the results from drying chamber experiments, weather forecasts, and separation between structures. Knowledge about the structures at risk and their use is also important. The benefits of an automated fire danger rating system would be that the society can better plan for potentially severe cold-climate fires and thereby limit the negative impacts of such fires.

  20. Projected changes of rainfall event characteristics for the Czech Republic

    Directory of Open Access Journals (Sweden)

    Svoboda Vojtěch

    2016-12-01

    Full Text Available Projected changes of warm season (May–September rainfall events in an ensemble of 30 regional climate model (RCM simulations are assessed for the Czech Republic. Individual rainfall events are identified using the concept of minimum inter-event time and only heavy events are considered. The changes of rainfall event characteristics are evaluated between the control (1981–2000 and two scenario (2020–2049 and 2070–2099 periods. Despite a consistent decrease in the number of heavy rainfall events, there is a large uncertainty in projected changes in seasonal precipitation total due to heavy events. Most considered characteristics (rainfall event depth, mean rainfall rate, maximum 60-min rainfall intensity and indicators of rainfall event erosivity are projected to increase and larger increases appear for more extreme values. Only rainfall event duration slightly decreases in the more distant scenario period according to the RCM simulations. As a consequence, the number of less extreme heavy rainfall events as well as the number of long events decreases in majority of the RCM simulations. Changes in most event characteristics (and especially in characteristics related to the rainfall intensity depend on changes in radiative forcing and temperature for the future periods. Only changes in the number of events and seasonal total due to heavy events depend significantly on altitude.

  1. Acetaminophen (paracetamol) for the common cold in adults.

    Science.gov (United States)

    Li, Siyuan; Yue, Jirong; Dong, Bi Rong; Yang, Ming; Lin, Xiufang; Wu, Taixiang

    2013-07-01

    Acetaminophen is frequently prescribed for treating patients with the common cold, but there is little evidence as to whether it is effective. To determine the efficacy and safety of acetaminophen in the treatment of the common cold in adults. We searched CENTRAL 2013, Issue 1, Ovid MEDLINE (1950 to January week 5, 2013), EMBASE (1980 to February 2013), CINAHL (1982 to February 2013) and LILACS (1985 to February 2013). We included randomised controlled trials (RCTs) comparing acetaminophen to placebo or no treatment in adults with the common cold. Studies were included if the trials used acetaminophen as one ingredient of a combination therapy. We excluded studies in which the participants had complications. Primary outcomes included subjective symptom score and duration of common cold symptoms. Secondary outcomes were overall well being, adverse events and financial costs. Two review authors independently screened studies for inclusion, assessed risk of bias and extracted data. We performed standard statistical analyses. We included four RCTs involving 758 participants. We did not pool data because of heterogeneity in study designs, outcomes and time points. The studies provided sparse information about effects longer than a few hours, as three of four included studies were short trials of only four to six hours. Participants treated with acetaminophen had significant improvements in nasal obstruction in two of the four studies. One study showed that acetaminophen was superior to placebo in decreasing rhinorrhoea severity, but was not superior for treating sneezing and coughing. Acetaminophen did not improve sore throat or malaise in two of the four studies. Results were inconsistent for some symptoms. Two studies showed that headache and achiness improved more in the acetaminophen group than in the placebo group, while one study showed no difference between the acetaminophen and placebo group. None of the included studies reported the duration of common cold

  2. Seasonal evolution of faecal egg output by gastrointestinal worms in goats on communal farms in eastern Namibia

    Directory of Open Access Journals (Sweden)

    F.F. Kumba

    2003-11-01

    Full Text Available As a more detailed continuation of a previous study, faecal samples for worm egg counts were collected per rectum from ten marked adult animals in selected flocks of goats, in each of six villages evenly spread out in the communal farming district of Okakarara in eastern Namibia. The study was conducted on a monthly basis from August 1999 to July 2000. Average faecal worm egg counts (FECs were highest during the warm-wet season, much lower during the cold-dry months and moderate during the hot-dry season. Least square means of FECs were 2 140, 430 and 653 per gram of faeces for the three seasons, respectively. Seasonal variation in egg counts was significant (P < 0.0001. Gastrointestinal strongyles, and to a lesser extent Strongyloides species, were the predominant parasite groups identified in goats. Kidding rates peaked in the cold-dry season and mortality rates in the hot-dry season. Results of this study suggest that gastrointestinal parasitism may be a problem that accentuates the effect of poor nutrition on small ruminants during the season of food shortages in the east of Namibia and that the use of FECs per se to assess the severity of gastrointestinal parasitic infection in goats followed by chemoprophylactic strategic and / or tactical treatment, may not be the best approach to addressing the worm problem under resource-poor conditions. The use of the FAMACHA(c system that identifies severely affected animals for treatment is technically a better option for communal farmers.

  3. Winter sports athletes: long-term effects of cold air exposure.

    Science.gov (United States)

    Sue-Chu, Malcolm

    2012-05-01

    Athletes such as skaters and skiers inhale large volumes of cold air during exercise and shift from nasal to mouth breathing. Endurance athletes, like cross-country skiers, perform at 80% or more of their maximal oxygen consumption and have minute ventilations in excess of 100 l/min. Cold air is always dry, and endurance exercise results in loss of water and heat from the lower respiratory tract. In addition, athletes can be exposed to indoor and outdoor pollutants during the competitive season and during all-year training. Hyperpnoea with cold dry air represents a significant environmental stress to the airways. Winter athletes have a high prevalence of respiratory symptoms and airway hyper-responsiveness to methacholine and hyperpnoea. The acute effects of exercise in cold air are neutrophil influx as demonstrated in lavage fluid and airway epithelial damage as demonstrated by bronchoscopy. Upregulation of pro-inflammatory cytokines has been observed in horses. Chronic endurance training damages the epithelium of the small airways in mice. Airway inflammation has been observed on bronchoscopy of cross-country skiers and in dogs after a 1100-mile endurance race in Alaska. Neutrophilic and lymphocytic inflammation with remodelling is present in bronchial biopsies from skiers. Repeated peripheral airway hyperpnoea with dry air causes inflammation and remodelling in dogs. As it is currently unknown if these airway changes are reversible upon cessation of exposure, preventive measures to diminish exposure of the lower airways to cold air should be instituted by all winter sports athletes.

  4. Wind energy under cold climate conditions

    Energy Technology Data Exchange (ETDEWEB)

    Maribo Pedersen, B.

    1999-03-01

    There is an increasing interest in wind energy production under different climatic conditions, among them cold climate and icing conditions. More and more wind turbines are being installed in cold climates and even adapted technology has been developed for that environment. Various national activities are going on in at least Finland, Canada, Italy, Sweden, etc. and international collaboration has been carried out within the European Union's Non-nuclear energy programme. Wind turbine operation is affected by both the cold temperatures and the formation of ice on the blades and the supporting structure. Cold temperatures can be handled by material selections known in other technical fields but to prevent icing, new techniques have to be - and have been - developed. Icing affects the reliability of anemometers, which concerns both turbine control and resource estimation, and changes the aerodynamics of the blades, which eventually stops the turbine. In addition, occasional icing events can locally affect public safety. The development of applied technology has entered some different paths and different solutions are tried out. As the applications are entering a commercial phase, these is a request to gather the experiences and monitor the reliability in a form that can be utilised by developers, manufactureres, consultants and other tenderers. The Topical Experts Meeting will focus on site classification, operational experiences, modelling and mesurements of ice induced loads and safety aspects. (EHS)

  5. Impact of cold temperature on Euro 6 passenger car emissions.

    Science.gov (United States)

    Suarez-Bertoa, Ricardo; Astorga, Covadonga

    2018-03-01

    Hydrocarbons, CO, NOx, NH 3 , N 2 O, CO 2 and particulate matter emissions affect air quality, global warming and human health. Transport sector is an important source of these pollutants and high pollution episodes are often experienced during the cold season. However, EU vehicle emissions regulation at cold ambient temperature only addresses hydrocarbons and CO vehicular emissions. For that reason, we have studied the impact that cold ambient temperatures have on Euro 6 diesel and spark ignition (including: gasoline, ethanol flex-fuel and hybrid vehicles) vehicle emissions using the World-harmonized Light-duty Test Cycle (WLTC) at -7 °C and 23 °C. Results indicate that when facing the WLTC at 23 °C the tested vehicles present emissions below the values set for type approval of Euro 6 vehicles (still using NEDC), with the exception of NOx emissions from diesel vehicles that were 2.3-6 times higher than Euro 6 standards. However, emissions disproportionally increased when vehicles were tested at cold ambient temperature (-7 °C). High solid particle number (SPN) emissions (>1 × 10 11 # km -1 ) were measured from gasoline direct injection (GDI) vehicles and gasoline port fuel injection vehicles. However, only diesel and GDI SPN emissions are currently regulated. Results show the need for a new, technology independent, procedure that enables the authorities to assess pollutant emissions from vehicles at cold ambient temperatures. Harmful pollutant emissions from spark ignition and diesel vehicles are strongly and negatively affected by cold ambient temperatures. Only hydrocarbon, CO emissions are currently regulated at cold temperature. Therefore, it is of great importance to revise current EU winter vehicle emissions regulation. Copyright © 2017 The Authors. Published by Elsevier Ltd.. All rights reserved.

  6. Excess cardiovascular mortality associated with cold spells in the Czech Republic

    Directory of Open Access Journals (Sweden)

    Kyncl Jan

    2009-01-01

    Full Text Available Abstract Background The association between cardiovascular mortality and winter cold spells was evaluated in the population of the Czech Republic over 21-yr period 1986–2006. No comprehensive study on cold-related mortality in central Europe has been carried out despite the fact that cold air invasions are more frequent and severe in this region than in western and southern Europe. Methods Cold spells were defined as periods of days on which air temperature does not exceed -3.5°C. Days on which mortality was affected by epidemics of influenza/acute respiratory infections were identified and omitted from the analysis. Excess cardiovascular mortality was determined after the long-term changes and the seasonal cycle in mortality had been removed. Excess mortality during and after cold spells was examined in individual age groups and genders. Results Cold spells were associated with positive mean excess cardiovascular mortality in all age groups (25–59, 60–69, 70–79 and 80+ years and in both men and women. The relative mortality effects were most pronounced and most direct in middle-aged men (25–59 years, which contrasts with majority of studies on cold-related mortality in other regions. The estimated excess mortality during the severe cold spells in January 1987 (+274 cardiovascular deaths is comparable to that attributed to the most severe heat wave in this region in 1994. Conclusion The results show that cold stress has a considerable impact on mortality in central Europe, representing a public health threat of an importance similar to heat waves. The elevated mortality risks in men aged 25–59 years may be related to occupational exposure of large numbers of men working outdoors in winter. Early warnings and preventive measures based on weather forecast and targeted on the susceptible parts of the population may help mitigate the effects of cold spells and save lives.

  7. Variability and trends in dry day frequency and dry event length in the southwestern United States

    Science.gov (United States)

    McCabe, Gregory J.; Legates, David R.; Lins, Harry F.

    2010-01-01

    Daily precipitation from 22 National Weather Service first-order weather stations in the southwestern United States for water years 1951 through 2006 are used to examine variability and trends in the frequency of dry days and dry event length. Dry events with minimum thresholds of 10 and 20 consecutive days of precipitation with less than 2.54 mm are analyzed. For water years and cool seasons (October through March), most sites indicate negative trends in dry event length (i.e., dry event durations are becoming shorter). For the warm season (April through September), most sites also indicate negative trends; however, more sites indicate positive trends in dry event length for the warm season than for water years or cool seasons. The larger number of sites indicating positive trends in dry event length during the warm season is due to a series of dry warm seasons near the end of the 20th century and the beginning of the 21st century. Overall, a large portion of the variability in dry event length is attributable to variability of the El Niño–Southern Oscillation, especially for water years and cool seasons. Our results are consistent with analyses of trends in discharge for sites in the southwestern United States, an increased frequency in El Niño events, and positive trends in precipitation in the southwestern United States.

  8. Seasonal variations and source apportionment of atmospheric PM2.5-bound polycyclic aromatic hydrocarbons in a mixed multi-function area of Hangzhou, China.

    Science.gov (United States)

    Lu, Hao; Wang, Shengsheng; Li, Yun; Gong, Hui; Han, Jingyi; Wu, Zuliang; Yao, Shuiliang; Zhang, Xuming; Tang, Xiujuan; Jiang, Boqiong

    2017-07-01

    To reveal the seasonal variations and sources of PM 2.5 -bound polycyclic aromatic hydrocarbons (PAHs) during haze and non-haze episodes, daily PM 2.5 samples were collected from March 2015 to February 2016 in a mixed multi-function area in Hangzhou, China. Ambient concentrations of 16 priority-controlled PAHs were determined. The sums of PM 2.5 -bound PAH concentrations during the haze episodes were 4.52 ± 3.32 and 13.6 ± 6.29 ng m -3 in warm and cold seasons, respectively, which were 1.99 and 1.49 times those during the non-haze episodes. Four PAH sources were identified using the positive matrix factorization model and conditional probability function, which were vehicular emissions (45%), heavy oil combustion (23%), coal and natural gas combustion (22%), and biomass combustion (10%). The four source concentrations of PAHs consistently showed higher levels in the cold season, compared with those in the warm season. Vehicular emissions were the most considerable sources that result in the increase of PM 2.5 -bound PAH levels during the haze episodes, and heavy oil combustion played an important role in the aggravation of haze pollution. The analysis of air mass back trajectories indicated that air mass transport had an influence on the PM 2.5 -bound PAH pollution, especially on the increased contributions from coal combustion and vehicular emissions in the cold season.

  9. High NDVI and Potential Canopy Photosynthesis of South American Subtropical Forests despite Seasonal Changes in Leaf Area Index and Air Temperature

    Directory of Open Access Journals (Sweden)

    Piedad M. Cristiano

    2014-02-01

    Full Text Available The canopy photosynthesis and carbon balance of the subtropical forests are not well studied compared to temperate and tropical forest ecosystems. The main objective of this study was to assess the seasonal dynamics of Normalized Difference Vegetation Index (NDVI and potential canopy photosynthesis in relation to seasonal changes in leaf area index (LAI, chlorophyll concentration, and air temperatures of NE Argentina subtropical forests throughout the year. We included in the analysis several tree plantations (Pinus, Eucalyptus and Araucaria species that are known to have high productivity. Field studies in native forests and tree plantations were conducted; stem growth rates, LAI and leaf chlorophyll concentration were measured. MODIS satellite-derived LAI (1 km SIN Grid and NDVI (250m SIN Grid from February 2000 to 2012 were used as a proxy of seasonal dynamics of potential photosynthetic activity at the stand level. The remote sensing LAI of the subtropical forests decreased every year from 6 to 5 during the cold season, similar to field LAI measurements, when temperatures were 10 °C lower than during the summer. The yearly maximum NDVI values were observed during a few months in autumn and spring (March through May and November, respectively because high and low air temperatures may have a small detrimental effect on photosynthetic activity during both the warm and the cold seasons. Leaf chlorophyll concentration was higher during the cold season than the warm season which may have a compensatory effect on the seasonal variation of the NDVI values. The NDVI of the subtropical forest stands remained high and fairly constant throughout the year (the intra-annual coefficient of variation was 1.9%, and were comparable to the values of high-yield tree plantations. These results suggest that the humid subtropical forests in NE Argentina potentially could maintain high canopy photosynthetic activity throughout the year and thus this ecosystem may

  10. Daily indoor-to-outdoor temperature and humidity relationships: a sample across seasons and diverse climatic regions.

    Science.gov (United States)

    Nguyen, Jennifer L; Dockery, Douglas W

    2016-02-01

    The health consequences of heat and cold are usually evaluated based on associations with outdoor measurements collected at a nearby weather reporting station. However, people in the developed world spend little time outdoors, especially during extreme temperature events. We examined the association between indoor and outdoor temperature and humidity in a range of climates. We measured indoor temperature, apparent temperature, relative humidity, dew point, and specific humidity (a measure of moisture content in air) for one calendar year (2012) in a convenience sample of eight diverse locations ranging from the equatorial region (10 °N) to the Arctic (64 °N). We then compared the indoor conditions to outdoor values recorded at the nearest airport weather station. We found that the shape of the indoor-to-outdoor temperature and humidity relationships varied across seasons and locations. Indoor temperatures showed little variation across season and location. There was large variation in indoor relative humidity between seasons and between locations which was independent of outdoor airport measurements. On the other hand, indoor specific humidity, and to a lesser extent dew point, tracked with outdoor, airport measurements both seasonally and between climates, across a wide range of outdoor temperatures. These results suggest that, in general, outdoor measures of actual moisture content in air better capture indoor conditions than outdoor temperature and relative humidity. Therefore, in studies where water vapor is among the parameters of interest for examining weather-related health effects, outdoor measurements of actual moisture content can be more reliably used as a proxy for indoor exposure than the more commonly examined variables of temperature and relative humidity.

  11. The impact of winter cold weather on acute myocardial infarctions in Portugal

    International Nuclear Information System (INIS)

    Vasconcelos, João; Freire, Elisabete; Almendra, Ricardo

    2013-01-01

    Mortality due to cardiovascular diseases shows a seasonal trend that can be associated with cold weather. Portugal is the European country with the highest excess winter mortality, but nevertheless, the relationship between cold weather and health is yet to be assessed. The main aim of this study is to identify the contribution of cold weather to cardiovascular diseases within Portugal. Poisson regression analysis based on generalized additive models was applied to estimate the influence of a human-biometeorological index (PET) on daily hospitalizations for myocardial infarction. The main results revealed a negative effect of cold weather on acute myocardial infarctions in Portugal. For every degree fall in PET during winter, there was an increase of up to 2.2% (95% CI = 0.9%; 3.3%) in daily hospital admissions. This paper shows the need for public policies that will help minimize or, indeed, prevent exposure to cold. -- Highlights: ► We model the relationship between daily hospitalizations due to myocardial infarctions and cold weather in Portugal. ► We use Physiological Equivalent temperature (PET) as main explanatory variable. ► We adjust the models to confounding factors such as influenza and air pollution. ► Daily hospitalizations increased up to 2.2% per degree fall of PET during winter. ► Exposure to cold weather has a negative impact on human health in Portugal. -- There is an increase of up to 2.2% in daily hospitalizations due to acute myocardial infarctions per degree fall of thermal index during the winter months in Portugal

  12. Seasonal trends, chemical speciation and source apportionment of fine PM in Tehran

    Science.gov (United States)

    Arhami, Mohammad; Hosseini, Vahid; Zare Shahne, Maryam; Bigdeli, Mostafa; Lai, Alexandra; Schauer, James J.

    2017-03-01

    Frequent air pollution episodes have been reported for Tehran, Iran, mainly because of critically high levels of fine particulate matter (PM2.5). The composition and sources of these particles are poorly known, so this study aims to identify the major components and heavy metals in PM2.5 along with their seasonal trends and associated sources. 24-hour PM2.5 samples were collected at a main residential station every 6 days for a full year from February 2014 to February 2015. The samples were analyzed for ions, organic carbon (including water-soluble and insoluble portions), elemental carbon (EC), and all detectable elements. The dominant mass components, which were determined by means of chemical mass closure, were organic matter (35%), dust (25%), non-sea salt sulfate (11%), EC (9%), ammonium (5%), and nitrate (2%). Organic matter and EC together comprised 44% of fine PM on average (increased to >70% in the colder season), which reflects the significance of anthropogenic urban sources (i.e. vehicles). The contributions of different components varied considerably throughout the year, particularly the dust component that varied from 7% in the cold season to 56% in the hot and dry season. Principal component analyses were applied, resulting in 5 major source factors that explained 85% of the variance in fine PM. Factor 1, representing soil dust, explained 53%; Factor 2 denotes heavy metals mainly found in industrial sources and accounted for 18%; and rest of factors, mainly representing combustion sources, explained 14% of the variation. The levels of major heavy metals were further evaluated, and their trends showed considerable increases during cold seasons. The results of this study provide useful insight to fine PM in Tehran, which could help in identifying their health effects and sources, and also adopting effective control strategies.

  13. Survival strategies of freshwater insects in cold environments

    Directory of Open Access Journals (Sweden)

    Valeria LENCIONI

    2004-09-01

    Full Text Available At high latitudes and altitudes, ice formation is a major variable affecting survival of freshwater fauna and hence the abundance and composition of invertebrate communities. Freezing, but also desiccation and anoxia, are lethal threats to all life stages of aquatic insects, from the eggs to the adults. During cold periods, the aquatic stages commonly remain in or move to a portion of the water body that will not freeze or dry (e.g., deep waters of lakes, springs and hyporheic zone where they can remain active. Less frequently they migrate to habitats that will freeze at the onset of winter. Insects have developed a complex of strategies to survive at their physiological temperature minimum, comprising (a morphological (melanism, reduction in size, hairiness/pubescence, brachyptery and aptery, (b behavioural (basking in the sun, changes in feeding and mating habit, parthenogenesis, polyploidy, ovoviviparity, habitat selection and cocoon building, (c ecological (extension of development to several years by quiescence or diapause and reduction of the number of generations per year, (d physiological and biochemical (freezing tolerance and freezing avoidance adaptations. Most species develop a combination of these survival strategies that can be different in the aquatic and terrestrial phase. Freezing avoidance and freezing tolerance may be accompanied by diapause. Both cold hardiness and diapause manifest during the unfavourable season and: (i involve storage of food resources (commonly glycogen and lipids; (ii are under hormonal control (ecdysone and juvenile hormone; (iii involve a depression or suppression of the oxidative metabolism with mitochondrial degradation. However, where the growing season is reduced to a few weeks, insects may develop cold hardiness without entering diapause, maintaining in the haemolymph a high concentration of Thermal Hysteris Proteins (THPs for the entire year and a slow but continuous growth. A synthesis of

  14. Music season coming soon

    CERN Multimedia

    CERN Bulletin in collaboration with Julio Rosenfeld

    2012-01-01

    On 16 June, CERN’s music season will open with Music on the Lawn. The event is the CERN Music Club’s contribution to the Fete de la Musique and will take place on the terrace of Restaurant 1 from 2 p.m. to 8 p.m. The Hardronic Festival, CERN’s long-running rock festival, will be held on the evenings of 20 and 21 July in Prévessin, on the terrace behind Restaurant 3. If you would like to help with the organisation, please contact the Music Club by e-mail: music.club@cern.ch.   The Canettes Blues Band during the 2011 Hardronic Festival. (© Christoph Balle, 2010). Summer is coming, and along with it comes the music season. CERN will be hosting its two annual rock music concerts: Music on the Lawn and the Hardronic Festival. The two events are organised by the CERN Music Club, which has been sharing the enjoyment of good music with its numerous fans for many years. “Music on the Lawn was originally created so that the members of the Mus...

  15. Sampling frequency of ciliated protozoan microfauna for seasonal distribution research in marine ecosystems.

    Science.gov (United States)

    Xu, Henglong; Yong, Jiang; Xu, Guangjian

    2015-12-30

    Sampling frequency is important to obtain sufficient information for temporal research of microfauna. To determine an optimal strategy for exploring the seasonal variation in ciliated protozoa, a dataset from the Yellow Sea, northern China was studied. Samples were collected with 24 (biweekly), 12 (monthly), 8 (bimonthly per season) and 4 (seasonally) sampling events. Compared to the 24 samplings (100%), the 12-, 8- and 4-samplings recovered 94%, 94%, and 78% of the total species, respectively. To reveal the seasonal distribution, the 8-sampling regime may result in >75% information of the seasonal variance, while the traditional 4-sampling may only explain sampling frequency, the biotic data showed stronger correlations with seasonal variables (e.g., temperature, salinity) in combination with nutrients. It is suggested that the 8-sampling events per year may be an optimal sampling strategy for ciliated protozoan seasonal research in marine ecosystems. Copyright © 2015 Elsevier Ltd. All rights reserved.

  16. Heat pipe based cold energy storage systems for datacenter energy conservation

    International Nuclear Information System (INIS)

    Singh, Randeep; Mochizuki, Masataka; Mashiko, Koichi; Nguyen, Thang

    2011-01-01

    In the present paper, design and economics of the novel type of thermal control system for datacenter using heat pipe based cold energy storage has been proposed and discussed. Two types of cold energy storage system namely: ice storage system and cold water storage system are explained and sized for datacenter with heat output capacity of 8800 kW. Basically, the cold energy storage will help to reduce the chiller running time that will save electricity related cost and decrease greenhouse gas emissions resulting from the electricity generation from non-renewable sources. The proposed cold energy storage system can be retrofit or connected in the existing datacenter facilities without major design changes. Out of the two proposed systems, ice based cold energy storage system is mainly recommended for datacenters which are located in very cold locations and therefore can offer long term seasonal storage of cold energy within reasonable cost. One of the potential application domains for ice based cold energy storage system using heat pipes is the emergency backup system for datacenter. Water based cold energy storage system provides more compact size with short term storage (hours to days) and is potential for datacenters located in areas with yearly average temperature below the permissible cooling water temperature (∼25 o C). The aforesaid cold energy storage systems were sized on the basis of metrological conditions in Poughkeepsie, New York. As an outcome of the thermal and cost analysis, water based cold energy storage system with cooling capability to handle 60% of datacenter yearly heat load will provide an optimum system size with minimum payback period of 3.5 years. Water based cold energy storage system using heat pipes can be essentially used as precooler for chiller. Preliminary results obtained from the experimental system to test the capability of heat pipe based cold energy storage system have provided satisfactory outcomes and validated the proposed

  17. Legionella species diversity and dynamics from surface reservoir to tap water: from cold adaptation to thermophily.

    Science.gov (United States)

    Lesnik, René; Brettar, Ingrid; Höfle, Manfred G

    2016-05-01

    Water samples of the Drinking Water Supply System (DWSS) of the city of Braunschweig were analysed for its Legionella species composition using genus-specific PCR amplicons and single-strand conformation polymorphism (SSCP) fingerprint analyses based on 16S rRNA genes. These analyses comprised the whole supply chain including raw water, treatment process and large-scale storage, and a seasonal study of finished drinking water sampled monthly from cold and hot tap water. Treatment of raw water had a major impact on Legionella species by reducing their diversity and abundances. The Legionella species composition of the tap water was highly distinct from that of both source waters. In cold water, 8-14 different phylotypes of Legionella (PTLs) were observed per sample with relative abundances ranging from >1% to 53%. In hot water, L. pneumophila was present during all seasons at high relative abundances (8-40%) accompanied by 5-14 other PTLs of which 6 PTLs were in common with cold water. This thermophilic Legionella community, including L. pneumophila, was able to grow in the hot water above 50 °C. Such thermophilic Legionella populations are of general relevance for drinking water management and public health, but also for the ecology and evolution of the genus Legionella.

  18. Excess winter mortality and cold temperatures in a subtropical city, Guangzhou, China.

    Directory of Open Access Journals (Sweden)

    Chun-Quan Ou

    Full Text Available BACKGROUND: A significant increase in mortality was observed during cold winters in many temperate regions. However, there is a lack of evidence from tropical and subtropical regions, and the influence of ambient temperatures on seasonal variation of mortality was not well documented. METHODS: This study included 213,737 registered deaths from January 2003 to December 2011 in Guangzhou, a subtropical city in Southern China. Excess winter mortality was calculated by the excess percentage of monthly mortality in winters over that of non-winter months. A generalized linear model with a quasi-Poisson distribution was applied to analyze the association between monthly mean temperature and mortality, after controlling for other meteorological measures and air pollution. RESULTS: The mortality rate in the winter was 26% higher than the average rate in other seasons. On average, there were 1,848 excess winter deaths annually, with around half (52% from cardiovascular diseases and a quarter (24% from respiratory diseases. Excess winter mortality was higher in the elderly, females and those with low education level than the young, males and those with high education level, respectively. A much larger winter increase was observed in out-of-hospital mortality compared to in-hospital mortality (45% vs. 17%. We found a significant negative correlation of annual excess winter mortality with average winter temperature (rs=-0.738, P=0.037, but not with air pollution levels. A 1 °C decrease in monthly mean temperature was associated with an increase of 1.38% (95% CI:0.34%-2.40% and 0.88% (95% CI:0.11%-1.64% in monthly mortality at lags of 0-1 month, respectively. CONCLUSION: Similar to temperate regions, a subtropical city Guangzhou showed a clear seasonal pattern in mortality, with a sharper spike in winter. Our results highlight the role of cold temperature on the winter mortality even in warm climate. Precautionary measures should be strengthened to mitigate

  19. Liquefied petroleum gas cold burn sustained while refueling a car.

    Science.gov (United States)

    Scarr, Bronwyn; Mitra, Biswadev; Maini, Amit; Cleland, Heather

    2010-02-01

    There have been few cases of cold burn related to the exposure of liquid petroleum gas (LPG). We present the case of a young woman exposed to LPG while refueling her car who sustained partial thickness burns to the dorsum of her hand. Contact with LPG leaking from a pressurized system causes tissue damage because of cold injury. Immediate management of LPG is extrapolated from the management of frostbite. The increasing use of LPG mandates an awareness of prevention strategies and management principles in the setting of adverse events.

  20. Heat waves and cold spells: an analysis of policy response and perceptions of vulnerable populations in the UK

    OpenAIRE

    Johanna Wolf; W Neil Adger; Irene Lorenzoni

    2010-01-01

    Heat waves and cold spells pose ongoing seasonal risks to the health and well-being of vulnerable individuals. Current attempts to address these risks in the UK are implemented through fuel-poverty strategies and heat-wave planning. This paper examines evidence from the UK on whether heat waves and cold spells are addressed differently by public policy in the UK given that risks are mediated by similar perceptions that shape behavioural responses by vulnerable individuals. It is based on a re...

  1. Normal and seasonally amplified indoor radon levels

    International Nuclear Information System (INIS)

    Gammage, R.B.; Dudney, C.S.; Wilson, D.L.; King, D.

    1995-01-01

    Winter and summer indoor radon measurements are reported for 121 houses in Freehold, New Jersey. When presented as winter:summer ratios of indoor radon, the data closely approximate a lognormal distribution. The geometric mean is 1.49. Freehold is located on the fairly flat coastal plain. The winter:summer ratios are believed to represent the norm for regions of the U.S. with cold winters and hot summers. The Freehold data set can be compared to corresponding data sets from other locations to suggest seasonal perturbations of indoor radon arising from unusual causes

  2. Effect of seasonal changes in use patterns and cold inlet water temperature on water-heating loads

    Energy Technology Data Exchange (ETDEWEB)

    Abrams, D.W.; Shedd, A.C. [D.W. Abrams, P.E. and Associates, Atlanta, GA (United States)

    1996-11-01

    This paper presents long-term test data obtained in 20 commercial buildings and 16 residential sites. The information illustrates the effects of variations in hot water load determinants and the effect on energy use. It also is useful as a supplement to the load profiles presented in the ASHRAE Handbooks and other design references. The commercial facilities include supermarkets, fast-food restaurants, full-service restaurants, commercial kitchens, a motel, a nursing home, a hospital, a bakery, and laundry facilities. The residential sites ere selected to provide test sites with higher-than-average hot water use. They include 13 single-family detached residences, one 14-unit apartment building, and two apartment laundries. Test data are available at measurement intervals of 1 minute for the residential sites and 15 minutes for the commercial sites. Summary data in tabular and graphical form are presented for average daily volumetric hot water use and cold inlet water temperature. Measured cold inlet water temperature and volumetric hot water use figures are compared to values typically used for design and analysis. Conclusions are offered regarding the effect of cold water inlet temperature and variations in hot water use on water-heating load and energy use. Recommendations for the use of the information presented in water-heating system design, performance optimization, and performance analysis conclude the paper.

  3. Context-dependent effects of cold stress on behavioral, physiological, and life-history traits of the red flour beetle.

    Science.gov (United States)

    Scharf, Inon; Wertheimer, Keren-Or; Xin, Joy Lim; Gilad, Tomer; Goldenberg, Inna; Subach, Aziz

    2017-06-20

    Animals are exposed in nature to a variety of stressors. While stress is generally harmful, mild stress can also be beneficial and contribute to reproduction and survival. We studied the effect of five cold shock events versus a single cold shock and a control group, representing three levels of stress (harsh, mild, and no stress), on behavioral, physiological, and life-history traits of the red flour beetle (Tribolium castaneum, Herbst 1797). Beetles exposed to harsh cold stress were less active than a control group: they moved less and failed more frequently to detect a food patch. Their probability to mate was also lower. Beetle pairs exposed to harsh cold stress frequently failed to reproduce at all, and if reproducing, females laid fewer eggs, which were, as larvae in mid-development, smaller than those in the control group. However, harsh cold stress led to improved female starvation tolerance, probably due to enhanced lipid accumulation. Harsh cold shock also improved tolerance to an additional cold shock compared to the control. Finally, a single cold shock event negatively affected fewer measured response variables than the harsh cold stress, but also enhanced neither starvation tolerance nor tolerance to an additional cold shock. The consequences of a harsher cold stress are thus not solely detrimental but might even enhance survival under stressful conditions. Under benign conditions, nevertheless, harsh stress impedes beetle performance. The harsh stress probably shifted the balance point of the survival-reproduction trade-off, a shift that did not take place following exposure to mild stress. © 2017 Institute of Zoology, Chinese Academy of Sciences.

  4. Seasonal variability in biological carbon biomass standing stocks and production in the surface layers of the Bay of Bengal

    Digital Repository Service at National Institute of Oceanography (India)

    Ramaiah, N.; Fernandes, V.; Paul, J.T.; Jyothibabu, R.; Gauns, M.; Jayraj, E.A.

    ). Incidentally it was mostly decoupled with chl a and PP. Cold-core eddies observed during most sampled seasons seem to bear an enhancing influence on the overall biological productivity processes...

  5. Is cold or warm blood cardioplegia superior for myocardial protection?

    Science.gov (United States)

    Abah, Udo; Roberts, Patrick Garfjeld; Ishaq, Muhammad; De Silva, Ravi

    2012-01-01

    A best evidence topic in cardiac surgery was written according to a structured protocol. The question addressed was whether the use of warm or cold blood cardioplegia has superior myocardial protection. More than 192 papers were found using the reported search, of which 20 represented the best evidence to answer the clinical question. The authors, journal, date, country of publication, patient group studied, study type, relevant outcomes and results of these papers are tabulated. A good breadth of high-level evidence addressing this clinical dilemma is available, including a recent meta-analysis and multiple large randomized clinical trials. Yet despite this level of evidence, no clear significant clinical benefit has been demonstrated by warm or cold blood cardioplegia. This suggests that neither method is significantly superior and that both provide similar efficacy of myocardial protection. The meta-analysis, including 41 randomized control trials (5879 patients in total), concluded that although a lower cardiac enzyme release and improved postoperative cardiac index was demonstrated in the warm cardioplegia group, this benefit was not reflected in clinical outcomes, which were similar in both groups. This theme of benefit in biochemical markers, physiological metrics and non-fatal postoperative events in the warm cardioplegia group ran throughout the literature, in particular the ‘Warm Heart investigators’ who conducted a randomized trial of 1732 patients, demonstrated a reduction in postoperative low output syndrome (6.1 versus 9.3%, P = 0.01) in the warm cardioplegia group, but no significant drop in 30-day all-cause mortality (1.4 versus 2.5%, P = 0.12). However, their later follow-up indicates non-fatal postoperative events predict reduced late survival, independent of cardioplegia. A minority of studies suggested a benefit of cold cardioplegia over warm in particular patient subgroups: One group conducted a retrospective study of 520 patients who

  6. Influence of Northeast Monsoon cold surges on air quality in Southeast Asia

    Science.gov (United States)

    Ashfold, M. J.; Latif, M. T.; Samah, A. A.; Mead, M. I.; Harris, N. R. P.

    2017-10-01

    Ozone (O3) is an important ground-level pollutant. O3 levels and emissions of O3 precursors have increased significantly over recent decades in East Asia and export of this O3 eastward across the Pacific Ocean is well documented. Here we show that East Asian O3 is also transported southward to tropical Southeast (SE) Asia during the Northeast Monsoon (NEM) season (defined as November to February), and that this transport pathway is especially strong during 'cold surges'. Our analysis employs reanalysis data and measurements from surface sites in Peninsular Malaysia, both covering 2003-2012, along with trajectory calculations. Using a cold surge index (northerly winds at 925 hPa averaged over 105-110°E, 5°N) to define sub-seasonal strengthening of the NEM winds, we find the largest changes in a region covering much of the Indochinese Peninsula and surrounding seas. Here, the levels of O3 and another key pollutant, carbon monoxide, calculated by the Monitoring Atmospheric Composition and Climate (MACC) Reanalysis are on average elevated by, respectively, >40% (∼15 ppb) and >60% (∼80 ppb) during cold surges. Further, in the broader region of SE Asia local afternoon exceedances of the World Health Organization's air quality guideline for O3 (100 μg m-3, or ∼50 ppb, averaged over 8 h) largely occur during these cold surges. Day-to-day variations in available O3 observations at surface sites on the east coast of Peninsular Malaysia and in corresponding parts of the MACC Reanalysis are similar, and are clearly linked to cold surges. However, observed O3 levels are typically ∼10-20 ppb lower than the MACC Reanalysis. We show that these observations are also subject to influence from local urban pollution. In agreement with past work, we find year-to-year variations in cold surge activity related to the El Nino-Southern Oscillation (ENSO), but this does not appear to be the dominant influence of ENSO on atmospheric composition in this region. Overall, our study

  7. Seasonality of livebirths and climatic factors in Italian regions (1863-1933

    Directory of Open Access Journals (Sweden)

    Gabriele Ruiu

    2017-07-01

    Full Text Available Birth seasonality is a phenomenon that characterizes almost all the populations of the world. In spite of this, the causes underlying these seasonal fluctuations represent an as yet unsolved puzzle. Two main theoretical approaches have been proposed to explain birth seasonality. The first encompasses a social explanation and emphasizes the role of social, economic and cultural factors in determining the optimal moment (from a social perspective for conception (e.g., according to the cycle of agricultural workload, religious festivity, marriage seasonality, etc.. The second theoretical approach encompasses an environmental explanation and focuses on the role that climatic factors (e.g., temperature, rainfall, light intensity, etc. play in determining the optimal moment of conception from a biological perspective. Our paper may be collocated in the latter strand of the literature. The aim is to investigate the effects of temperature on conceptions, and subsequently on the seasonality of livebirths, while controlling for a possible social confounding effect, i.e. the seasonal pattern of marriage. To achieve this end, we empirically investigate the role of temperature as well as that of marriage seasonality in Italian regions for the period stretching from the Italian unification to the eve of World War II. We find that extreme temperatures (both cold and hot negatively affect the number of births. At the same time, marriage seasonality also seems to be an important explicative factor of the seasonal fluctuation of live births.

  8. Thermo-mechanical Design Methodology for ITER Cryodistribution cold boxes

    Science.gov (United States)

    Shukla, Vinit; Patel, Pratik; Das, Jotirmoy; Vaghela, Hitensinh; Bhattacharya, Ritendra; Shah, Nitin; Choukekar, Ketan; Chang, Hyun-Sik; Sarkar, Biswanath

    2017-04-01

    The ITER cryo-distribution (CD) system is in charge of proper distribution of the cryogen at required mass flow rate, pressure and temperature level to the users; namely the superconducting (SC) magnets and cryopumps (CPs). The CD system is also capable to use the magnet structures as a thermal buffer in order to operate the cryo-plant as much as possible at a steady state condition. A typical CD cold box is equipped with mainly liquid helium (LHe) bath, heat exchangers (HX’s), cryogenic valves, filter, heaters, cold circulator, cold compressor and process piping. The various load combinations which are likely to occur during the life cycle of the CD cold boxes are imposed on the representative model and impacts on the system are analyzed. This study shows that break of insulation vacuum during nominal operation (NO) along with seismic event (Seismic Level-2) is the most stringent load combination having maximum stress of 224 MPa. However, NO+SMHV (Séismes Maximaux Historiquement Vraisemblables = Maximum Historically Probable Earthquakes) load combination is having the least safety margin and will lead the basis of the design of the CD system and its sub components. This paper presents and compares the results of different load combinations which are likely to occur on a typical CD cold box.

  9. The I.A.G./A.I.G. SEDIBUD (Sediment Budgets in Cold Environments) Program (2005 - 2017): Key activities and outcomes

    Science.gov (United States)

    Beylich, Achim A.

    2017-04-01

    Amplified climate change and ecological sensitivity of high-latitude and high-altitude cold climate environments has been highlighted as a key global environmental issue. Projected climate change in largely undisturbed cold regions is expected to alter melt-season duration and intensity, along with the number of extreme rainfall events, total annual precipitation and the balance between snowfall and rainfall. Similarly, changes to the thermal balance are expected to reduce the extent of permafrost and seasonal ground frost and increase active-layer depths. These combined effects will undoubtedly change Earth surface environments in cold regions and will alter the fluxes of sediments, solutes and nutrients. However, the absence of quantitative data and coordinated analysis to understand the sensitivity of the Earth surface environment are acute in cold regions. Contemporary cold climate environments generally provide the opportunity to identify solute and sedimentary systems where anthropogenic impacts are still less important than the effects of climate change. Accordingly, it is still possible to develop a library of baseline fluvial yields and sedimentary budgets before the natural environment is completely transformed. The SEDIBUD (Sediment Budgets in Cold Environments) Program, building on the European Science Foundation (ESF) Network SEDIFLUX (Sedimentary Source-to-Sink Fluxes in Cold Environments, since 2004) was formed in 2005 as a new Program (Working Group) of the International Association of Geomorphologists (I.A.G./A.I.G.) to address this still existing key knowledge gap. SEDIBUD (2005-2017) has currently about 400 members worldwide and the Steering Committee of this international program is composed of eleven scientists from ten different countries. The central research question of this global program is to: Assess and model the contemporary sedimentary fluxes in cold climates, with emphasis on both particulate and dissolved components. Research carried

  10. A CloudSat-CALIPSO View of Cloud and Precipitation Properties Across Cold Fronts over the Global Oceans

    Science.gov (United States)

    Naud, Catherine M.; Posselt, Derek J.; van den Heever, Susan C.

    2015-01-01

    The distribution of cloud and precipitation properties across oceanic extratropical cyclone cold fronts is examined using four years of combined CloudSat radar and CALIPSO lidar retrievals. The global annual mean cloud and precipitation distributions show that low-level clouds are ubiquitous in the post frontal zone while higher-level cloud frequency and precipitation peak in the warm sector along the surface front. Increases in temperature and moisture within the cold front region are associated with larger high-level but lower mid-/low level cloud frequencies and precipitation decreases in the cold sector. This behavior seems to be related to a shift from stratiform to convective clouds and precipitation. Stronger ascent in the warm conveyor belt tends to enhance cloudiness and precipitation across the cold front. A strong temperature contrast between the warm and cold sectors also encourages greater post-cold-frontal cloud occurrence. While the seasonal contrasts in environmental temperature, moisture, and ascent strength are enough to explain most of the variations in cloud and precipitation across cold fronts in both hemispheres, they do not fully explain the differences between Northern and Southern Hemisphere cold fronts. These differences are better explained when the impact of the contrast in temperature across the cold front is also considered. In addition, these large-scale parameters do not explain the relatively large frequency in springtime post frontal precipitation.

  11. Understanding Flood Seasonality and Its Temporal Shifts within the Contiguous United States

    Energy Technology Data Exchange (ETDEWEB)

    Ye, Sheng [Institute of Hydrology and Water Resources, School of Civil Engineering, Zhejiang University, Hangzhou, China; Li, Hong-Yi [Pacific Northwest National Laboratory, Richland, Washington; Leung, L. Ruby [Pacific Northwest National Laboratory, Richland, Washington; Guo, Jiali [College of Civil and Hydropower Engineering, China Three Gorges University, Yichang, China; State Key Laboratory of Water Resources and Hydropower Engineering Science, Wuhan University, Wuhan, China; Ran, Qihua [Institute of Hydrology and Water Resources, School of Civil Engineering, Zhejiang University, Hangzhou, China; Demissie, Yonas [Department of Civil and Environmental Engineering, Washington State University Tri-Cities, Richland, Washington; Sivapalan, Murugesu [Department of Geography and Geographic Information Science, University of Illinois at Urbana–Champaign, Champaign, Illinois; Department of Civil and Environmental Engineering, University of Illinois at Urbana–Champaign, Urbana, Illinois

    2017-07-01

    Understanding the causes of flood seasonality is critical for better flood management. This study examines the seasonality of annual maximum floods (AMF) and its changes before and after 1980 at over 250 natural catchments across the contiguous United States. Using circular statistics to define a seasonality index, our analysis focuses on the variability of the flood occurrence date. Generally, catchments with more synchronized seasonal water and energy cycles largely inherit their seasonality of AMF from that of annual maximum rainfall (AMR). In contrast, the seasonality of AMF in catchments with loosely synchronized water and energy cycles are more influenced by high antecedent storage, which is responsible for the amplification of the seasonality of AMF over that of AMR. This understanding then effectively explains a statistically significant shift of flood seasonality detected in some catchments in the recent decades. Catchments where the antecedent soil water storage has increased since 1980 exhibit increasing flood seasonality while catchments that have experienced increases in storm rainfall before the floods have shifted towards floods occurring more variably across the seasons. In the eastern catchments, a concurrent widespread increase in event rainfall magnitude and reduced soil water storage have led to a more variable timing of floods. Our findings of the role of antecedent storage and event rainfall on the flood seasonality provide useful insights for understanding future changes in flood seasonality as climate models projected changes in extreme precipitation and aridity over land.

  12. Seasonal cues induce phenotypic plasticity of Drosophila suzukii to enhance winter survival.

    Science.gov (United States)

    Shearer, Peter W; West, Jessica D; Walton, Vaughn M; Brown, Preston H; Svetec, Nicolas; Chiu, Joanna C

    2016-03-22

    As global climate change and exponential human population growth intensifies pressure on agricultural systems, the need to effectively manage invasive insect pests is becoming increasingly important to global food security. Drosophila suzukii is an invasive pest that drastically expanded its global range in a very short time since 2008, spreading to most areas in North America and many countries in Europe and South America. Preliminary ecological modeling predicted a more restricted distribution and, for this reason, the invasion of D. suzukii to northern temperate regions is especially unexpected. Investigating D. suzukii phenology and seasonal adaptations can lead to a better understanding of the mechanisms through which insects express phenotypic plasticity, which likely enables invasive species to successfully colonize a wide range of environments. We describe seasonal phenotypic plasticity in field populations of D. suzukii. Specifically, we observed a trend of higher proportions of flies with the winter morph phenotype, characterized by darker pigmentation and longer wing length, as summer progresses to winter. A laboratory-simulated winter photoperiod and temperature (12:12 L:D and 10 °C) were sufficient to induce the winter morph phenotype in D. suzukii. This winter morph is associated with increased survival at 1 °C when compared to the summer morph, thus explaining the ability of D. suzukii to survive cold winters. We then used RNA sequencing to identify gene expression differences underlying seasonal differences in D. suzukii physiology. Winter morph gene expression is consistent with known mechanisms of cold-hardening such as adjustments to ion transport and up-regulation of carbohydrate metabolism. In addition, transcripts involved in oogenesis and DNA replication were down-regulated in the winter morph, providing the first molecular evidence of a reproductive diapause in D. suzukii. To date, D. suzukii cold resistance studies suggest that this

  13. A simple and inexpensive method for determining cold sensitivity and adaptation in mice.

    Science.gov (United States)

    Brenner, Daniel S; Golden, Judith P; Vogt, Sherri K; Gereau, Robert W

    2015-03-17

    Cold hypersensitivity is a serious clinical problem, affecting a broad subset of patients and causing significant decreases in quality of life. The cold plantar assay allows the objective and inexpensive assessment of cold sensitivity in mice, and can quantify both analgesia and hypersensitivity. Mice are acclimated on a glass plate, and a compressed dry ice pellet is held against the glass surface underneath the hindpaw. The latency to withdrawal from the cooling glass is used as a measure of cold sensitivity. Cold sensation is also important for survival in regions with seasonal temperature shifts, and in order to maintain sensitivity animals must be able to adjust their thermal response thresholds to match the ambient temperature. The Cold Plantar Assay (CPA) also allows the study of adaptation to changes in ambient temperature by testing the cold sensitivity of mice at temperatures ranging from 30 °C to 5 °C. Mice are acclimated as described above, but the glass plate is cooled to the desired starting temperature using aluminum boxes (or aluminum foil packets) filled with hot water, wet ice, or dry ice. The temperature of the plate is measured at the center using a filament T-type thermocouple probe. Once the plate has reached the desired starting temperature, the animals are tested as described above. This assay allows testing of mice at temperatures ranging from innocuous to noxious. The CPA yields unambiguous and consistent behavioral responses in uninjured mice and can be used to quantify both hypersensitivity and analgesia. This protocol describes how to use the CPA to measure cold hypersensitivity, analgesia, and adaptation in mice.

  14. Optimization of Domestic-Size Renewable Energy System Designs Suitable for Cold Climate Regions

    Science.gov (United States)

    Akpan, Itoro Etim; Sasaki, Masafumi; Endoh, Noboru

    Five different kinds of domestic-size renewable energy system configurations for very cold climate regions were investigated. From detailed numerical modeling and system simulations, it was found that the consumption of fuel oil for the auxiliary boiler in residential-type households can almost be eliminated with a renewable energy system that incorporates photovoltaic panel arrays for electricity generation and two storage tanks: a well-insulated electric water storage tank that services the hot water loads, and a compact boiler/geothermal heat pump tank for room heating during very cold seasons. A reduction of Greenhouse Gas Emissions (GHG) of about 28% was achieved for this system compared to an equivalent conventional system. The near elimination of the use of fuel oil in this system makes it very promising for very cold climate regions in terms of energy savings because the running cost is not so dependent on the unstable nature of global oil prices.

  15. The SEDIBUD (Sediment Budgets in Cold Environments) Programme: Current activities and future key tasks

    Science.gov (United States)

    Beylich, A. A.; Lamoureux, S. F.; Decaulne, A.

    2012-04-01

    Projected climate change in cold regions is expected to alter melt season duration and intensity, along with the number of extreme rainfall events, total annual precipitation and the balance between snowfall and rainfall. Similarly, changes to the thermal balance are expected to reduce the extent of permafrost and seasonal ground frost and increase active layer depths. These effects will undoubtedly change surface environments in cold regions and alter the fluxes of sediments, nutrients and solutes, but the absence of quantitative data and coordinated process monitoring and analysis to understand the sensitivity of the Earth surface environment is acute in cold climate environments. The International Association of Geomorphologists (I.A.G./A.I.G.)SEDIBUD (Sediment Budgets in Cold Environments) Programme was formed in 2005 to address this existing key knowledge gap. SEDIBUD currently has about 400 members worldwide and the Steering Committee of this international programme is composed of ten scientists from eight different countries: Achim A. Beylich (Chair) (Norway), Armelle Decaulne (Secretary) (France), John C. Dixon (USA), Scott F. Lamoureux (Vice-Chair) (Canada), John F. Orwin (Canada), Jan-Christoph Otto (Austria), Irina Overeem (USA), Thorsteinn Saemundsson (Iceland), Jeff Warburton (UK), Zbigniew Zwolinski (Poland). The central research question of this global group of scientists is to: Assess and model the contemporary sedimentary fluxes in cold climates, with emphasis on both particulate and dissolved components. Initially formed as European Science Foundation (ESF) Network SEDIFLUX (2004-2006), SEDIBUD has further expanded to a global group of researchers with field research sites located in polar and alpine regions in the northern and southern hemisphere. Research carried out at each of the close to 50 defined SEDIBUD key test sites varies by programme, logistics and available resources, but typically represent interdisciplinary collaborations of

  16. Cold plate

    Energy Technology Data Exchange (ETDEWEB)

    Marroquin, Christopher M.; O' Connell, Kevin M.; Schultz, Mark D.; Tian, Shurong

    2018-02-13

    A cold plate, an electronic assembly including a cold plate, and a method for forming a cold plate are provided. The cold plate includes an interface plate and an opposing plate that form a plenum. The cold plate includes a plurality of active areas arranged for alignment over respective heat generating portions of an electronic assembly, and non-active areas between the active areas. A cooling fluid flows through the plenum. The plenum, at the non-active areas, has a reduced width and/or reduced height relative to the plenum at the active areas. The reduced width and/or height of the plenum, and exterior dimensions of cold plate, at the non-active areas allow the non-active areas to flex to accommodate surface variations of the electronics assembly. The reduced width and/or height non-active areas can be specifically shaped to fit between physical features of the electronics assembly.

  17. Temperature studies with the Asian citrus psyllid, Diaphorina citri: cold hardiness and temperature thresholds for oviposition.

    Science.gov (United States)

    Hall, David G; Wenninger, Erik J; Hentz, Matthew G

    2011-01-01

    This study was conducted to obtain information on the cold hardiness of the Asian citrus psyllid, Diaphorina citri Kuwayama (Hemiptera: Psyllidae), in Florida and to assess upper and lower temperature thresholds for oviposition. The psyllid is an important pest in citrus because it transmits the bacterial pathogens responsible for citrus greening disease, Huanglongbing, considered the most serious citrus disease worldwide. D. citri was first found in Florida during 1998, and the disease was discovered during 2005. Little was known regarding cold hardiness of D. citri, but Florida citrus is occasionally subjected to notable freeze events. Temperature and duration were each significant sources of variation in percent mortality of D. citri subjected to freeze events. Relatively large percentages of adults and nymphs survived after being exposed for several hours to temperatures as low as -5 to -6 °C. Relatively large percentages of eggs hatched after being exposed for several hours to temperatures as low as -8 °C. Research results indicated that adult D. citri become cold acclimated during the winter through exposure to cooler winter temperatures. There was no evidence that eggs became cold acclimated during winter. Cold acclimation in nymphs was not investigated. Research with adult D. citri from laboratory and greenhouse colonies revealed that mild to moderate freeze events were usually nonlethal to the D. citri irrespective of whether they were cold acclimated or not. Upper and lower temperature thresholds for oviposition were investigated because such information may be valuable in explaining the geographic distribution and potential spread of the pest from Florida as well as how cooler winter temperatures might limit population growth. The estimated lower and upper thresholds for oviposition were 16.0 and 41.6 °C, respectively; the estimated temperature of peak oviposition over a 48 h period was 29.6 °C.

  18. Forecasting Turbine Icing Events

    DEFF Research Database (Denmark)

    Davis, Neil; Hahmann, Andrea N.; Clausen, Niels-Erik

    2012-01-01

    In this study, we present a method for forecasting icing events. The method is validated at two European wind farms in with known icing events. The icing model used was developed using current ice accretion methods, and newly developed ablation algorithms. The model is driven by inputs from the WRF...... mesoscale model, allowing for both climatological estimates of icing and short term icing forecasts. The current model was able to detect periods of icing reasonably well at the warmer site. However at the cold climate site, the model was not able to remove ice quickly enough leading to large ice...

  19. The Recent Atlantic Cold Anomaly: Causes, Consequences, and Related Phenomena

    Science.gov (United States)

    Josey, Simon A.; Hirschi, Joel J.-M.; Sinha, Bablu; Duchez, Aurélie; Grist, Jeremy P.; Marsh, Robert

    2018-01-01

    Cold ocean temperature anomalies have been observed in the mid- to high-latitude North Atlantic on interannual to centennial timescales. Most notably, a large region of persistently low surface temperatures accompanied by a sharp reduction in ocean heat content was evident in the subpolar gyre from the winter of 2013-2014 to 2016, and the presence of this feature at a time of pervasive warming elsewhere has stimulated considerable debate. Here, we review the role of air-sea interaction and ocean processes in generating this cold anomaly and place it in a longer-term context. We also discuss the potential impacts of surface temperature anomalies for the atmosphere, including the North Atlantic Oscillation and European heat waves; contrast the behavior of the Atlantic with the extreme warm surface event that occurred in the North Pacific over a similar timescale; and consider the possibility that these events represent a response to a change in atmospheric planetary wave forcing.

  20. Variation in Admission Rates of Acute Coronary Syndrome Patients in Coronary Care Unit According to Different Seasons

    International Nuclear Information System (INIS)

    Lashari, M. N.; Soomro, K.

    2015-01-01

    Objective:Environmental stresses, especially extreme cold and hot weathers, have tendency to have more admissions for acute coronary syndromes. Due to scarcity of local data, we studied the variation in patient admission rates with acute coronary syndrome according to different seasons. Study Design: Descriptive study. Place and Duration of Study: Coronary Care Unit, Civil Hospital and Pakistan Steel Hospital, Karachi, from January 2011 to December 2011. Methodology: The study group comprised consecutive patients with acute coronary syndrome (unstable angina, Non ST-Elevation Myocardial Infarction (NSTEMI), ST-Elevation Myocardial Infarction (STEMI) admitted to the coronary care unit. Patients with stable angina and valvular heart disease were excluded. Data was analyzed for admission according to different seasons, (winter, spring, summer and autumn). Results: The mean age of the 428 cases was 48.5 ± 10.4 years (range 27 to 73 years). Among the study group, 261 (61%) and 167 (39%) cases were male and female respectively. ST-elevation myocardial infarction, non ST-elevation myocardial infarction and unstable angina were present in 206 (48%), 128 (30%) and 94 (22%) respectively. Among the 428 patients, 184 (43%) cases had hypertension, 133 (31%) cases were smokers, 103 (24%) cases had dyslipidemia and diabetes mellitus and 08 (2%) cases had history of premature coronary artery disease. The number of patients admissions with acute coronary syndrome tended to change with sudden change in season. It increased in Winter 158 (36.9%) and Summer 130 (30.3%) in comparison to Spring 80 (18.69%) and Autumn 60 (14.02%) season. Conclusion: It was found variation in admission rates of acute coronary syndrome patients according to different seasons. The number of admissions not only increased in the cold season (winter) but also in hot season (summer) with sudden changes in temperature. (author)

  1. Enhanced aridity and atmospheric high-pressure stability over the western Mediterranean during the North Atlantic cold events of the past 50 k.y.

    Science.gov (United States)

    Combourieu Nebout, N.; Turon, J. L.; Zahn, R.; Capotondi, L.; Londeix, L.; Pahnke, K.

    2002-10-01

    Multiproxy paleoenvironmental records (pollen and planktonic isotope) from Ocean Drilling Program Site 976 (Alboran Sea) document rapid ocean and climate variations during the last glacial that follow the Dansgaard-Oeschger climate oscillations seen in the Greenland ice core records, thus suggesting a close link of the Mediterranean climate swings with North Atlantic climates. Continental conditions rapidly oscillated through cold-arid and warm-wet conditions in the course of stadial-interstadial climate jumps. At the time of Heinrich events, i.e., maximum meltwater flux to the North Atlantic, western Mediterranean marine microflora and microfauna show rapid cooling correlated with increasing continental dryness. Enhanced aridity conceivably points to prolonged wintertime stability of atmospheric high-pressure systems over the southwestern Mediterranean in conjunction with cooling of the North Atlantic.

  2. Conceptualizing Cold Disasters

    DEFF Research Database (Denmark)

    Lauta, Kristian Cedervall; Dahlberg, Rasmus; Vendelø, Morten Thanning

    2017-01-01

    In the present article, we explore in more depth the particular circumstances and characteristics of governing what we call ‘cold disasters’, and thereby, the paper sets out to investigate how disasters in cold contexts distinguish themselves from other disasters, and what the implications hereof...... are for the conceptualization and governance of cold disasters. Hence, the paper can also be viewed as a response to Alexander’s (2012a) recent call for new theory in the field of disaster risk reduction. The article is structured in four overall parts. The first part, Cold Context, provides an overview of the specific...... conditions in a cold context, exemplified by the Arctic, and zooms in on Greenland to provide more specific background for the paper. The second part, Disasters in Cold Contexts, discusses “cold disasters” in relation to disaster theory, in order to, elucidate how cold disasters challenge existing...

  3. Meso-scale atmospheric events promote phytoplankton blooms in ...

    Indian Academy of Sciences (India)

    The Bay of Bengal is considered to be a low productive region compared to the Arabian Sea based on conventional seasonal observations. Such seasonal observations are not representative of a calendar year since the conventional approach might miss episodic high productive events associated with extreme ...

  4. Effects of cold working on the pitting corrosion behavior s of AISI 304 stainless steels

    Energy Technology Data Exchange (ETDEWEB)

    Jung, Kee Min; Kim, Jong Soo; Kim, Young Jun; Kwon, Houk Sang [KAIST, Daejon (Korea, Republic of)

    2015-12-15

    These microstructural changes by cold working can lead improvement of mechanical properties, however from a corrosion resistant point of view, the effects of cold working on the corrosion resistance of stainless steel have been argued. Several studies has been focused on the influence of cold working on the localized corrosion resistance of stainless steels. However, the opinions about the role of cold working on the localized corrosion resistance are highly in consistence. Some studies report that the pitting potential of austenitic stainless steels decreased with cold working level, on the other hands, other studies claimed that the pitting resistance was increased by cold working. Therefore it is necessary to verify how cold working affects pitting corrosion behavior of austenitic stainless steels. In the present work, the influence of cold working on the localized corrosion of AISI 304stainless steel in the neutral chloride solution was studied based on point defect model (PDM). The fraction of deformation-induced martensite was linearly increased with cold rolling level. Through cold rolling, the pitting potential was decreased, the metastable pitting event density was significantly increased and the repassivation potential was decreased. The overall localized corrosion resistance was decreased with cold working, however cold working level increased from 30 % to 50 %, localized corrosion resistance was recovered. The accumulated cation vacancy generates a void at metal/film interface, therefore film breakdown accelerates for cold worked alloys.

  5. Effects of cold working on the pitting corrosion behavior s of AISI 304 stainless steels

    International Nuclear Information System (INIS)

    Jung, Kee Min; Kim, Jong Soo; Kim, Young Jun; Kwon, Houk Sang

    2015-01-01

    These microstructural changes by cold working can lead improvement of mechanical properties, however from a corrosion resistant point of view, the effects of cold working on the corrosion resistance of stainless steel have been argued. Several studies has been focused on the influence of cold working on the localized corrosion resistance of stainless steels. However, the opinions about the role of cold working on the localized corrosion resistance are highly in consistence. Some studies report that the pitting potential of austenitic stainless steels decreased with cold working level, on the other hands, other studies claimed that the pitting resistance was increased by cold working. Therefore it is necessary to verify how cold working affects pitting corrosion behavior of austenitic stainless steels. In the present work, the influence of cold working on the localized corrosion of AISI 304stainless steel in the neutral chloride solution was studied based on point defect model (PDM). The fraction of deformation-induced martensite was linearly increased with cold rolling level. Through cold rolling, the pitting potential was decreased, the metastable pitting event density was significantly increased and the repassivation potential was decreased. The overall localized corrosion resistance was decreased with cold working, however cold working level increased from 30 % to 50 %, localized corrosion resistance was recovered. The accumulated cation vacancy generates a void at metal/film interface, therefore film breakdown accelerates for cold worked alloys

  6. Mechanism of seasonal eddy kinetic energy variability in the eastern equatorial Pacific Ocean

    Science.gov (United States)

    Wang, Minyang; Du, Yan; Qiu, Bo; Cheng, Xuhua; Luo, Yiyong; Chen, Xiao; Feng, Ming

    2017-04-01

    Enhanced mesoscale eddy activities or tropical instability waves (TIWs) exist along the northern front of the cold tongue in the eastern equatorial Pacific Ocean. In this study, we investigate seasonal variability of eddy kinetic energy (EKE) over this region and its associated dynamic mechanism using a global, eddy-resolving ocean general circulation model (OGCM) simulation, the equatorial mooring data, and satellite altimeter observations. The seasonal-varying enhanced EKE signals are found to expand westward from 100°W in June to 180°W in December between 0°N and 6°N. This westward expansion in EKE is closely connected to the barotropically-baroclinically unstable zonal flows that are in thermal-wind balance with the seasonal-varying thermocline trough along 4°N. By adopting an 1½-layer reduced-gravity model, we confirm that the seasonal perturbation of the thermocline trough is dominated by the anticyclonic wind stress curl forcing, which develops due to southerly winds along 4°N from June to December.

  7. Study of exposure to cold stress and body physiological responses in auto mechanic employees in Hamadan city

    Directory of Open Access Journals (Sweden)

    Keivan Saedpanah

    2017-09-01

    Full Text Available Introduction: Continuous exposure to cold air is considered to be a hazardous agent in the workplace in cold seasons. This study aimed to determine the level of cold stress and relation with physiological responses in auto mechanic employees. Method: This cross-sectional study was conducted in the winter of 1395 on auto mechanic employees in Hamadan city. Physiological responses during daily activity were measured in accordance with ISO 9886 standard method. Environmental air measures like air temperature and air velocity were measured simultaneously and cold stress indexes were also determined. Data was analyzed using SPSS 21 software. Result: The result showed that mean wind chill index, equivalent chill temperature and required clothing insulation were 489.97±47.679 kcal/m2.h, 13.78± 1.869 0c and 2.04 ± 0.246 clo, respectively. According to the results of cold stress indexes, the studied employees are exposed to cold stress. Pearson correlation test showed that there are significant relationship between cold stress indexes with physiological responses (p<0.05, however, IREQ min showed more correlation than the others.  There is also a significant relationship between body fat percentage and deep temperature (p<0.05, r=0.314. Conclusion: The result confirmed that IREQ min index has high validity for estimation of cold stress among auto mechanic employees. Moreover, the increase of body fat percentage leads to an increase of cold tolerance power of employees.

  8. Role of Acclimatization in Weather-Related Human Mortality During the Transition Seasons of Autumn and Spring in a Thermally Extreme Mid-Latitude Continental Climate

    Science.gov (United States)

    de Freitas, Christopher R.; Grigorieva, Elena A.

    2015-01-01

    Human mortality is closely related to natural climate-determined levels of thermal environmental stress and the resulting thermophysiological strain. Most climate-mortality research has focused on seasonal extremes during winter and summer when mortality is the highest, while relatively little attention has been paid to mortality during the transitional seasons of autumn and spring. The body acclimatizes to heat in the summer and cold in winter and readjusts through acclimatization during the transitions between the two during which time the body experiences the thermophysiological strain of readjustment. To better understand the influences of weather on mortality through the acclimatization process, the aim here is to examine the periods that link very cold and very warms seasons. The study uses the Acclimatization Thermal Strain Index (ATSI), which is a comparative measure of short-term thermophysiological impact on the body. ATSI centers on heat exchange with the body’s core via the respiratory system, which cannot be protected. The analysis is based on data for a major city in the climatic region of the Russian Far East characterized by very hot summers and extremely cold winters. The results show that although mortality peaks in winter (January) and is at its lowest in summer (August), there is not a smooth rise through autumn nor a smooth decline through spring. A secondary peak occurs in autumn (October) with a smaller jump in May. This suggests the acclimatization from warm-to-cold produces more thermophysiological strain than the transition from cold-to-warm. The study shows that ATSI is a useful metric for quantifying the extent to which biophysical adaptation plays a role in increased strain on the body during re-acclimatization and for this reason is a more appropriate climatic indictor than air temperature alone. The work gives useful bioclimatic information on risks involved in transitional seasons in regions characterized by climatic extremes. This

  9. Validation of a limited area model over Dome C, Antarctic Plateau, during winter

    Energy Technology Data Exchange (ETDEWEB)

    Gallee, Hubert; Gorodetskaya, Irina V. [Laboratoire de Glaciologie et de Geophysique de l' Environnement, CNRS, 54, rue Moliere, BP. 96, St Martin d' Heres Cedex (France)

    2010-01-15

    The limited area model MAR (Modele Atmospherique Regional) is validated over the Antarctic Plateau for the period 2004-2006, focussing on Dome C during the cold season. MAR simulations are made by initializing the model once and by forcing it through its lateral and top boundaries by the ECMWF operational analyses. Model outputs compare favourably with observations from automatic weather station (AWS), radiometers and atmospheric soundings. MAR is able to simulate the succession of cold and warm events which occur at Dome C during winter. Larger longwave downwelling fluxes (LWD) are responsible for higher surface air temperatures and weaker surface inversions during winter. Warm events are better simulated when the small Antarctic precipitating snow particles are taken into account in radiative transfer computations. MAR stratosphere cools during the cold season, with the coldest temperatures occurring in conjunction with warm events at the surface. The decrease of saturation specific humidity associated with these coldest temperatures is responsible for the formation of polar stratospheric clouds (PSCs) especially in August-September. PSCs then contribute to the surface warming by increasing the surface downwelling longwave flux. (orig.)

  10. Study of Cycling Air-Cooling System with a Cold Accumulator for Micro Gas-Turbine Installations

    Science.gov (United States)

    Ochkov, V. F.; Stepanova, T. A.; Katenev, G. M.; Tumanovskii, V. A.; Borisova, P. N.

    2018-05-01

    Using the cycling air-cooling systems of the CTIC type (Combustion Turbine Inlet Cooling) with a cold accumulator in a micro gas-turbine installation (micro-GTI) to preserve its capacity under the seasonal temperature rise of outside air is described. Water ice is used as the body-storage in the accumulators, and ice water (water at 0.5-1.0°C) is used as the body that cools air. The ice water circulates between the accumulator and the air-water heat exchanger. The cold accumulator model with renewable ice resources is considered. The model contains the heat-exchanging tube lattice-evaporator covered with ice. The lattice is cross-flowed with water. The criterion heat exchange equation that describes the process in the cold accumulator under consideration is presented. The calculations of duration of its active operation were performed. The dependence of cold accumulator service life on water circulation rate was evaluated. The adequacy of the design model was confirmed experimentally in the mock-up of the cold accumulator with a refrigerating machine periodically creating a 200 kg ice reserve in the reservoir-storage. The design model makes it possible to determine the weight of ice reserve of the discharged cold accumulator for cooling the cycle air in the operation of a C-30 type micro- GTI produced by the Capstone Company or micro-GTIs of other capacities. Recommendations for increasing the working capacity of cold accumulators of CTIC-systems of a micro-GTI were made.

  11. Migration redefined? Seasonality, movements and group ...

    African Journals Online (AJOL)

    The migration of Southern Hemisphere humpback whales Megaptera novaeangliae between their feeding and breeding areas has thus far been considered a highly predictable and seasonal event. However, previous observations on the humpbacks that pass through the nearshore waters of the west coast of South Africa ...

  12. Improved Windows for Cold Climates

    DEFF Research Database (Denmark)

    Laustsen, Jacob Birck; Svendsen, Svend

    2005-01-01

    considerably by reducing the frame width, which results in a larger transparent area causing a larger solar gain but still main-taining a low thermal transmittance. Using three layers of glass with large gaps, using very slim frame profiles, and omitting the edge constructions that normally causes thermal...... windows with improved energy performance. Traditionally evaluation of the energy performance of windows has focused on the thermal transmittance, but as windows differ from the rest of the building envelope by allowing solar energy to enter the building, the total solar energy transmittance is equally...... important. In the heating season in cold climates the solar gain through windows can be utilized for space heating which results in a corresponding reduction in the energy production that is often based on fossil fuels. A suitable quantity for evaluating the energy performance of windows in a simple...

  13. Cold urticaria. Dissociation of cold-evoked histamine release and urticara following cold challenge.

    Science.gov (United States)

    Keahey, T M; Greaves, M W

    1980-02-01

    Nine patients with acquired cold urticaria were studied to assess the effects of beta-adrenergic agents, xanthines, and corticosteroids on cold-evoked histamine release from skin in vivo. The patients, in all of whom an immediate urticarial response developed after cooling of the forearm, demonstrated release of histamine into the venous blood draining that forearm. Following treatment with aminophylline and albuterol in combination or prednisone alone, suppression of histamine release occurred in all but one patient. In some patients, this was accompanied by a subjective diminution in pruritus or buring, but there was no significant improvement in the ensuing edema or erythema. In one patient, total suppression of histamine release was achieved without any effect on whealing and erythema in response to cold challenge. Our results suggest that histamine is not central to the pathogenesis of vascular changes in acquired cold urticaria.

  14. Holiday season for a healthy heart.

    Science.gov (United States)

    Stamps, Deborah C; Carr, Marcella L

    2012-12-01

    The term "holiday heart" is defined as an acute cardiac arrhythmia or conduction disturbance associated with heavy alcohol intake in individuals with no known heart disease, but in whom heart rhythm is restored to normal with abstinence of alcohol. This article provides a brief overview of the literature on this topic, discusses causes of increased cardiac events during the holiday season, describes a patient profile and the effect on patients' health as well as on their families, and provides suggestions to decrease the risk of holiday heart during the festive season. Copyright © 2012 Elsevier Inc. All rights reserved.

  15. On the distributions of annual and seasonal daily rainfall extremes in central Arizona and their spatial variability

    Science.gov (United States)

    Mascaro, Giuseppe

    2018-04-01

    This study uses daily rainfall records of a dense network of 240 gauges in central Arizona to gain insights on (i) the variability of the seasonal distributions of rainfall extremes; (ii) how the seasonal distributions affect the shape of the annual distribution; and (iii) the presence of spatial patterns and orographic control for these distributions. For this aim, recent methodological advancements in peak-over-threshold analysis and application of the Generalized Pareto Distribution (GPD) were used to assess the suitability of the GPD hypothesis and improve the estimation of its parameters, while limiting the effect of short sample sizes. The distribution of daily rainfall extremes was found to be heavy-tailed (i.e., GPD shape parameter ξ > 0) during the summer season, dominated by convective monsoonal thunderstorms. The exponential distribution (a special case of GPD with ξ = 0) was instead showed to be appropriate for modeling wintertime daily rainfall extremes, mainly caused by cold fronts transported by westerly flow. The annual distribution exhibited a mixed behavior, with lighter upper tails than those found in summer. A hybrid model mixing the two seasonal distributions was demonstrated capable of reproducing the annual distribution. Organized spatial patterns, mainly controlled by elevation, were observed for the GPD scale parameter, while ξ did not show any clear control of location or orography. The quantiles returned by the GPD were found to be very similar to those provided by the National Oceanic and Atmospheric Administration (NOAA) Atlas 14, which used the Generalized Extreme Value (GEV) distribution. Results of this work are useful to improve statistical modeling of daily rainfall extremes at high spatial resolution and provide diagnostic tools for assessing the ability of climate models to simulate extreme events.

  16. Underestimated effects of low temperature during early growing season on carbon sequestration of a subtropical coniferous plantation

    Directory of Open Access Journals (Sweden)

    W.-J. Zhang

    2011-06-01

    Full Text Available The impact of air temperature in early growing season on the carbon sequestration of a subtropical coniferous plantation was discussed through analyzing the eddy flux observations at Qianyanzhou (QYZ site in southern China from 2003 to 2008. This site experienced two cold early growing seasons (with temperature anomalies of 2–5 °C in 2005 and 2008, and a severe summer drought in 2003.
    Results indicated that the low air temperature from January to March was the major factor controlling the inter-annual variations in net carbon uptake at this site, rather than the previously thought summer drought. The accumulative air temperature from January to February showed high correlation (R2=0.970, p<0.001 with the annual net ecosystem production (NEP. This was due to the controls of early-month temperature on the plant phenology developing and the growing season length at this subtropical site. The cold spring greatly shortened the growing season length and therefore reduced the carbon uptake period. The eddy flux observations showed a carbon loss of 4.04 g C m−2 per growing-season day at this coniferous forest site. On the other hand, the summer drought also reduced the net carbon uptake strength because the photosynthesis was more sensitive to water deficit stress than the ecosystem respiration. However, the impact of summer drought occurred within a relatively shorter period and the carbon sequestration went back to the normal level once the drought was relieved.

  17. Is freezing in the vaccine cold chain an ongoing issue? A literature review.

    Science.gov (United States)

    Hanson, Celina M; George, Anupa M; Sawadogo, Adama; Schreiber, Benjamin

    2017-04-19

    Vaccine exposure to temperatures below recommended ranges in the cold chain may decrease vaccine potency of freeze-sensitive vaccines leading to a loss of vaccine investments and potentially places children at risk of contracting vaccine preventable illnesses. This literature review is an update to one previously published in 2007 (Matthias et al., 2007), analyzing the prevalence of vaccine exposure to temperatures below recommendations throughout various segments of the cold chain. Overall, 45 studies included in this review assess temperature monitoring, of which 29 specifically assess 'too cold' temperatures. The storage segments alone were evaluated in 41 articles, 15 articles examined the transport segment and 4 studied outreach sessions. The sample size of the studies varied, ranging from one to 103 shipments and from three to 440 storage units. Among reviewed articles, the percentage of vaccine exposure to temperatures below recommended ranges during storage was 33% in wealthier countries and 37.1% in lower income countries. Vaccine exposure to temperatures below recommended ranges occurred during shipments in 38% of studies from higher income countries and 19.3% in lower income countries. This review highlights continuing issues of vaccine exposure to temperatures below recommended ranges during various segments of the cold chain. Studies monitoring the number of events vaccines are exposed to 'too cold' temperatures as well as the duration of these events are needed. Many reviewed studies emphasize the lack of knowledge of health workers regarding freeze damage of vaccines and how this has an effect on temperature monitoring. It is important to address this issue by educating vaccinators and cold chain staff to improve temperature maintenance and supply chain management, which will facilitate the distribution of potent vaccines to children. Copyright © 2017 The Authors. Published by Elsevier Ltd.. All rights reserved.

  18. Assessing the cold temperature effect on hospital visit by allergic rhinitis in Seoul, Korea.

    Science.gov (United States)

    Kim, Hyomi; Kim, Honghyok; Lee, Jong-Tae

    2018-08-15

    The association between temperature and health outcome has been studied in worldwide. However, studies for mild diseases such as AR, with high prevalence and considerable economic burden, are lacking compared to other relatively severe respiratory diseases. We aimed to assess the trend of hospital visit by AR and estimate the cold temperature effect on hospital visit by allergic rhinitis in Seoul, Korea, 2003-2011. We fitted generalized additive model with quasi-poisson distribution, controlling for humidity, long-term trend, day of week, national holiday, and influenza epidemic. We estimated the cumulative cold temperature effect (10%, -1.7°C) referent to 7.9°C for the considered lag periods using distributed lag non-linear model: vary from the day of hospital visit to 10days before. Stratified analysis by season was also conducted. To adjust for possible confounding effect of air pollutants, we additionally adjusted for PM 10 , O 3 and NO 2 respectively. Hospital visit counts and rates per 1,000,000 show increasing trend especially in elderly population (over 65years). Hospital visit rate is higher in children population (ageeffects were found in the total (1.094(95%CI: 1.037, 1.153)), male (1.100 (95%CI: 1.010, 1.163)), female (1.088 (95%CI: 1.059, 1.170)) and adult (1.113 (95%CI: 1.059, 1.170)) population with consideration of 3-day lag period. In the stratified analysis by the season, the strongest effect was shown in the autumn (Sep-Nov) season. Confounding effects by air pollutants were not found. In this study, we found significant increasing trend of hospital visit by AR. This study provides suggestive evidence of cold temperature effect on hospital visit by AR. To reduce the growing burden of AR, it is important to find possible related environmental risk factors. More studies should be conducted for better understanding of temperature effect on AR. Copyright © 2018 Elsevier B.V. All rights reserved.

  19. Impaired reproduction in Japanese Black cattle under cold environmental conditions.

    Science.gov (United States)

    Nabenishi, H; Yamazaki, A

    2017-06-01

    Environmental factors such as the temperature-humidity index (THI) are known to affect reproductive parameters in cattle. Therefore, here, we examined whether there was any correlation between the THI and the reproductive performance of Japanese Black cattle by analysing the first-service conception rates of 178,492 artificially inseminated cows across 9,833 herds in south-western Japan over a 3-year period. The daily mean (±SD) THI over the study period was 63.6 ± 11.3 (range: 41.4-81.5). The calving to first artificial insemination (AI) interval was significantly negatively correlated with THI in the month of AI (r = -.75, p reproductive performance in Japanese Black cattle and that the impact of the cold environment on the conception rate is attributable to a carryover effect from the cold season before AI rather than conditions at the time of AI. © 2017 Blackwell Verlag GmbH.

  20. Seasonal variation in thrombogenicity of blood: a word of caution.

    Science.gov (United States)

    Narang, Sumit; Banerjee, Amit; Satsangi, Deepak K; Geelani, Mohammad A

    2009-01-01

    Thrombogenicity of blood is known to have seasonal variations. The clinical implications of seasonal variations in the anticoagulation profile of patients with mechanical valves was assessed. Data of patients implanted with a mechanical heart valve for more than 3 months were collected at follow-up or on presentation to the emergency department. The mean time from the previous follow-up examination was 3.6 +/- 0.3 months. The number of patients with an international normalized ratio >3.5 and the incidence of hemorrhagic events peaked in hottest part of the year (June-July), with 128 cases of prolonged clotting and 43 hemorrhagic events in this period. The number of patients with rapid clotting and the incidence of embolic events peaked in coldest part of the year (December-January), with 120 cases of international normalized ratio <1.5 and 37 embolic events in this period. There was a significant correlation between temperature and thrombogenicity in patients with prosthetic heart valves on long-term anticoagulation.

  1. Cold fronts and reservoir limnology: an integrated approach towards the ecological dynamics of freshwater ecosystems.

    Science.gov (United States)

    Tundisi, J G; Matsumura-Tundisi, T; Pereira, K C; Luzia, A P; Passerini, M D; Chiba, W A C; Morais, M A; Sebastien, N Y

    2010-10-01

    In this paper the authors discuss the effects of cold fronts on the dynamics of freshwater ecosystems of southeast South America. Cold fronts originating from the Antarctic show a monthly frequency that promotes turbulence and vertical mixing in reservoirs with a consequence to homogenize nutrient distribution, dissolved oxygen and temperature. Weak thermoclines and the athelomixis process immediately before, during and after the passage of cold fronts interfere with phytoplankton succession in reservoirs. Cyanobacteria blooms in eutrophic reservoirs are frequently connected with periods of stratification and stability of the water column. Cold fronts in the Amazon and Pantanal lakes may produce fish killings during the process of "friagem" associated mixing events. Further studies will try to implement a model to predict the impact of cold fronts and prepare management procedures in order to cope with cyanobacteria blooms during warm and stable water column periods. Changes in water quality of reservoirs are expected during circulation periods caused by cold fronts.

  2. Cold fronts and reservoir limnology: an integrated approach towards the ecological dynamics of freshwater ecosystems

    Directory of Open Access Journals (Sweden)

    JG. Tundisi

    Full Text Available In this paper the authors discuss the effects of cold fronts on the dynamics of freshwater ecosystems of southeast South America. Cold fronts originating from the Antarctic show a monthly frequency that promotes turbulence and vertical mixing in reservoirs with a consequence to homogenize nutrient distribution, dissolved oxygen and temperature. Weak thermoclines and the athelomixis process immediately before, during and after the passage of cold fronts interfere with phytoplankton succession in reservoirs. Cyanobacteria blooms in eutrophic reservoirs are frequently connected with periods of stratification and stability of the water column. Cold fronts in the Amazon and Pantanal lakes may produce fish killings during the process of "friagem" associated mixing events. Further studies will try to implement a model to predict the impact of cold fronts and prepare management procedures in order to cope with cyanobacteria blooms during warm and stable water column periods. Changes in water quality of reservoirs are expected during circulation periods caused by cold fronts.

  3. Transport of biologically important nutrients by wind in an eroding cold desert

    Science.gov (United States)

    Sankey, Joel B.; Germino, Matthew J.; Benner, Shawn G.; Glenn, Nancy F.; Hoover, Amber N.

    2012-01-01

    Wind erosion following fire is an important landscape process that can result in the redistribution of ecologically important soil resources. In this study we evaluated the potential for a fire patch in a desert shrubland to serve as a source of biologically important nutrients to the adjacent, downwind, unburned ecosystem. We analyzed nutrient concentrations (P, K, Ca, Mg, Cu, Fe, Mn, Al) in wind-transported sediments, and soils from burned and adjacent unburned surfaces, collected during the first to second growing seasons after a wildfire that burned in 2007 in Idaho, USA in sagebrush steppe; a type of cold desert shrubland. We also evaluated the timing of potential wind erosion events and weather conditions that might have contributed to nutrient availability in downwind shrubland. Findings indicated that post-fire wind erosion resulted in an important, but transient, addition of nutrients on the downwind shrubland. Aeolian sediments from the burned area were enriched relative to both the up- and down-wind soil and indicated the potential for a fertilization effect through the deposition of the nutrient-enriched sediment during the first, but not second, summer after wildfire. Weather conditions that could have produced nutrient transport events might have provided increased soil moisture necessary to make nutrients accessible for plants in the desert environment. Wind transport of nutrients following fire is likely important in the sagebrush steppe as it could contribute to pulses of resource availability that might, for example, affect plant species differently depending on their phenology, and nutrient- and water-use requirements.

  4. TNFα and IL-6 Responses to Particulate Matter in Vitro: Variation According to PM Size, Season, and Polycyclic Aromatic Hydrocarbon and Soil Content

    Science.gov (United States)

    Manzano-León, Natalia; Serrano-Lomelin, Jesús; Sánchez, Brisa N.; Quintana-Belmares, Raúl; Vega, Elizabeth; Vázquez-López, Inés; Rojas-Bracho, Leonora; López-Villegas, Maria Tania; Vadillo-Ortega, Felipe; De Vizcaya-Ruiz, Andrea; Perez, Irma Rosas; O’Neill, Marie S.; Osornio-Vargas, Alvaro R.

    2015-01-01

    Background: Observed seasonal differences in particulate matter (PM) associations with human health may be due to their composition and to toxicity-related seasonal interactions. Objectives: We assessed seasonality in PM composition and in vitro PM pro-inflammatory potential using multiple PM samples. Methods: We collected 90 weekly PM10 and PM2.5 samples during the rainy-warm and dry-cold seasons in five urban areas with different pollution sources. The elements, polycyclic aromatic hydrocarbons (PAHs), and endotoxins identified in the samples were subjected to principal component analysis (PCA). We tested the potential of the PM to induce tumor necrosis factor alpha (TNFα) and interleukin 6 (IL-6) secretion in cultured human monocytes (THP-1), and we modeled pro-inflammatory responses using the component scores. Results: PM composition varied by size and by season. PCA identified two main components that varied by season. Combustion-related constituents (e.g., vanadium, benzo[a]pyrene, benzo[a]anthracene) mainly comprised component 1 (C1). Soil-related constituents (e.g., endotoxins, silicon, aluminum) mainly comprised component 2 (C2). PM from the rainy-warm season was high in C2. PM (particularly PM2.5) from the dry-cold season was rich in C1. Elevated levels of cytokine production were associated with PM10 and C2 (rainy-warm season), whereas reduced levels of cytokine production were associated with PM2.5 and C1 (dry-cold season). TNFα secretion was increased following exposure to PM with high (vs. low) C2 content, but TNFα secretion in response to PM was decreased following exposure to samples containing ≥ 0.1% of C1-related PAHs, regardless of C2 content. The results of the IL-6 assays suggested more complex interactions between PM components and particle size. Conclusions: Variations in PM soil and PAH content underlie seasonal and PM size–related patterns in TNFα secretion. These results suggest that the mixture of components in PM explains some

  5. Floods of the Lower Tisza from the late 17th century onwards: frequency, magnitude, seasonality and great flood events

    Science.gov (United States)

    Kiss, Andrea

    2016-04-01

    The present paper is based on a recently developed database including contemporary original, administrative, legal and private source materials (published and archival) as well as media reports related to the floods occurred on the lower sections of the Tisza river in Hungary, with special emphasis on the area of Szeged town. The study area is well-represented by contemporary source evidence from the late 17th century onwards, when the town and its broader area was reoccupied from the Ottoman Turkish Empire. Concerning the applied source materials, the main bases of investigation are the administrative (archival) sources such as town council protocols of Szeged and county meeting protocols of Csanád and Csongrád Counties. In these (legal-)administrative documents damaging events (natural/environmental hazards) were systematically recorded. Moreover, other source types such as taxation-related damage accounts as well as private and official reports, letters and correspondence (published, unpublished) were also included. Concerning published evidence, a most important source is flood reports in contemporary newspapers as well as town chronicles and other contemporary narratives. In the presentation the main focus is on the analysis of flood-rich flood-poor periods of the last ca. 330 years; moreover, the seasonality distribution as well as the magnitude of Tisza flood events are also discussed. Another important aim of the poster is to provide a short overview, in the form of case studies, on the greatest flood events (e.g. duration, magnitude, damages, multi-annual consequences), and their further impacts on the urban and countryside development as well as on (changes in) flood defence strategies. In this respect, especially two flood events, the great (1815-)1816 and the catastrophic 1879 flood (shortly with causes and consequences) - that practically erased Szeged town from the ground - are presented in more detail.

  6. The effect of transport time, season and position on the truck on stress response in rabbits

    OpenAIRE

    Liste, M.G; María, G. A.; García-Belenguer, S.; Chacón, G.; Gazzola, P.; Villarroel, M.

    2008-01-01

    The present study analyzed the effect of transport time, season and position on the truck on physiological stress response of commercial rabbits in Aragón (Spain). A total of 156 animals were sampled in a 2x2x3 factorial design testing two transport times: short, 1 hour (1hT) and long, 7 hours (7hT), in two different seasons: hot, during summer (HT) and cold during winter (CT), and three different positions on the truck: upper, middle or lower decks in multi-floor cages on rolling stands (MFR...

  7. Relationships of self-identified cold tolerance and cold-induced vasodilatation in the finger

    Science.gov (United States)

    Park, Joonhee; Lee, Joo-Young

    2016-04-01

    This study was conducted to investigate relationships of self-identified cold tolerance and cold-induced vasodilatation (CIVD) in the finger. Nine males and 34 females participated in the following 2 tests: a CIVD test and a self-reported survey. The CIVD test was conducted 30-min cold-water immersion (3.8 ± 0.3 °C) of the middle finger at an air temperature of 27.9 ± 0.1 °C. The self-reported questionnaire consisted of 28 questions about whole and local body cold and heat tolerances. By a cluster analysis on the survey results, the participants were divided into two groups: high self-identified cold tolerance (HSCT, n = 25) and low self-identified cold tolerance (LSCT, n = 18). LSCT had lower self-identified cold tolerance ( P cold or heat tolerance had relationships with cold tolerance index, T max, and amplitude ( P cold tolerance classified through a standardized survey could be a good index to predict physiological cold tolerance.

  8. The environmental impacts of beach sport tourism events: a case ...

    African Journals Online (AJOL)

    Durban has several established beach sport events. One of the many events is the Mr Price Pro, an internationally recognised surfi ng event, which takes place during the Vodacom Beach Africa festival, held annually during the July holiday season. This article examines the environmental impact of beach tourism events by ...

  9. Adaptation of psychrophilic and psychrotrophic sulfate-reducing bacteria to permanently cold marine environments

    DEFF Research Database (Denmark)

    Isaksen, MF; Jørgensen, BB

    1996-01-01

    degrees C. The rates of sulfate reduction were measured by the (SO42-)-S-35 tracer technique at different experimental temperatures in sediment slurries, In sediment slurries from Mariager Fjord, sulfate reduction showed a mesophilic temperature response which was comparable to that of other temperate...... environments, In sediment slurries from Antarctica, the metabolic activity of psychrotrophic bacteria was observed with a respiration optimum at 18 to 19 degrees C during short-term incubations, However, over a 1-week incubation, the highest respiration rate was observed at 12.5 degrees C. Growth......The potential for sulfate reduction at low temperatures was examined in two different cold marine sediments, Mariager Fjord (Denmark), which is permanently cold (3 to 6 degrees C) but surrounded by seasonally warmer environments, and the Weddell Sea (Antarctica), which is permanently below 0...

  10. Random and externally controlled occurrences of Dansgaard–Oeschger events

    Directory of Open Access Journals (Sweden)

    J. Lohmann

    2018-05-01

    Full Text Available Dansgaard–Oeschger (DO events constitute the most pronounced mode of centennial to millennial climate variability of the last glacial period. Since their discovery, many decades of research have been devoted to understand the origin and nature of these rapid climate shifts. In recent years, a number of studies have appeared that report emergence of DO-type variability in fully coupled general circulation models via different mechanisms. These mechanisms result in the occurrence of DO events at varying degrees of regularity, ranging from periodic to random. When examining the full sequence of DO events as captured in the North Greenland Ice Core Project (NGRIP ice core record, one can observe high irregularity in the timing of individual events at any stage within the last glacial period. In addition to the prevailing irregularity, certain properties of the DO event sequence, such as the average event frequency or the relative distribution of cold versus warm periods, appear to be changing throughout the glacial. By using statistical hypothesis tests on simple event models, we investigate whether the observed event sequence may have been generated by stationary random processes or rather was strongly modulated by external factors. We find that the sequence of DO warming events is consistent with a stationary random process, whereas dividing the event sequence into warming and cooling events leads to inconsistency with two independent event processes. As we include external forcing, we find a particularly good fit to the observed DO sequence in a model where the average residence time in warm periods are controlled by global ice volume and cold periods by boreal summer insolation.

  11. Random and externally controlled occurrences of Dansgaard-Oeschger events

    Science.gov (United States)

    Lohmann, Johannes; Ditlevsen, Peter D.

    2018-05-01

    Dansgaard-Oeschger (DO) events constitute the most pronounced mode of centennial to millennial climate variability of the last glacial period. Since their discovery, many decades of research have been devoted to understand the origin and nature of these rapid climate shifts. In recent years, a number of studies have appeared that report emergence of DO-type variability in fully coupled general circulation models via different mechanisms. These mechanisms result in the occurrence of DO events at varying degrees of regularity, ranging from periodic to random. When examining the full sequence of DO events as captured in the North Greenland Ice Core Project (NGRIP) ice core record, one can observe high irregularity in the timing of individual events at any stage within the last glacial period. In addition to the prevailing irregularity, certain properties of the DO event sequence, such as the average event frequency or the relative distribution of cold versus warm periods, appear to be changing throughout the glacial. By using statistical hypothesis tests on simple event models, we investigate whether the observed event sequence may have been generated by stationary random processes or rather was strongly modulated by external factors. We find that the sequence of DO warming events is consistent with a stationary random process, whereas dividing the event sequence into warming and cooling events leads to inconsistency with two independent event processes. As we include external forcing, we find a particularly good fit to the observed DO sequence in a model where the average residence time in warm periods are controlled by global ice volume and cold periods by boreal summer insolation.

  12. The value of using seasonality and meteorological variables to model intra-urban PM2.5 variation

    Science.gov (United States)

    Olvera Alvarez, Hector A.; Myers, Orrin B.; Weigel, Margaret; Armijos, Rodrigo X.

    2018-06-01

    A yearlong air monitoring campaign was conducted to assess the impact of local temperature, relative humidity, and wind speed on the temporal and spatial variability of PM2.5 in El Paso, Texas. Monitoring was conducted at four sites purposely selected to capture the local traffic variability. Effects of meteorological events on seasonal PM2.5 variability were identified. For instance, in winter low-wind and low-temperature conditions were associated with high PM2.5 events that contributed to elevated seasonal PM2.5 levels. Similarly, in spring, high PM2.5 events were associated with high-wind and low-relative humidity conditions. Correlation coefficients between meteorological variables and PM2.5 fluctuated drastically across seasons. Specifically, it was observed that for most sites correlations between PM2.5 and meteorological variables either changed from positive to negative or dissolved depending on the season. Overall, the results suggest that mixed effects analysis with season and site as fixed factors and meteorological variables as covariates could increase the explanatory value of LUR models for PM2.5.

  13. Can animal habitat use patterns influence their vulnerability to extreme climate events? An estuarine sportfish case study.

    Science.gov (United States)

    Boucek, Ross E; Heithaus, Michael R; Santos, Rolando; Stevens, Philip; Rehage, Jennifer S

    2017-10-01

    Global climate forecasts predict changes in the frequency and intensity of extreme climate events (ECEs). The capacity for specific habitat patches within a landscape to modulate stressors from extreme climate events, and animal distribution throughout habitat matrices during events, could influence the degree of population level effects following the passage of ECEs. Here, we ask (i) does the intensity of stressors of an ECE vary across a landscape? And (ii) Do habitat use patterns of a mobile species influence their vulnerability to ECEs? Specifically, we measured how extreme cold spells might interact with temporal variability in habitat use to affect populations of a tropical, estuarine-dependent large-bodied fish Common Snook, within Everglades National Park estuaries (FL US). We examined temperature variation across the estuary during cold disturbances with different degrees of severity, including an extreme cold spell. Second, we quantified Snook distribution patterns when the passage of ECEs is most likely to occur from 2012 to 2016 using passive acoustic tracking. Our results revealed spatial heterogeneity in the intensity of temperature declines during cold disturbances, with some habitats being consistently 3-5°C colder than others. Surprisingly, Snook distributions during periods of greatest risk to experience an extreme cold event varied among years. During the winters of 2013-2014 and 2014-2015 a greater proportion of Snook occurred in the colder habitats, while the winters of 2012-2013 and 2015-2016 featured more Snook observed in the warmest habitats. This study shows that Snook habitat use patterns could influence vulnerability to extreme cold events, however, whether Snook habitat use increases or decreases their vulnerability to disturbance depends on the year, creating temporally dynamic vulnerability. Faunal global change research should address the spatially explicit nature of extreme climate events and animal habitat use patterns to identify

  14. Seasonal variation in Chironomid emergence from coastal pools

    Directory of Open Access Journals (Sweden)

    Alexander T. Egan

    2015-07-01

    Full Text Available Understanding the phenology of emergences can be useful in determining seasonal chironomid life cycle patterns, which are often influenced by ice cover and temperature in cold climates. Lake Superior is the largest lake in North America and with a mean surface temperature of 3.9 °C influences regional climate. Coastal pools at Isle Royale, a wilderness archipelago in the northern part of the lake, occur in dense patches on low-gradient volcanic bedrock between the lakeshore and forest, creating variable microhabitats for Chironomidae. Four sites were sampled monthly from April to October, 2010. Surface-floating pupal exuviae were collected from a series of pools in two zones: a lower zone near the lake influenced by wave splash, and an upper zone near the forest and influenced by upland runoff. We used Jaccard’s and Whittaker’s diversity indexes to test community similarity across months. Temperature loggers in pools collected hourly readings for most of the study. Assemblage emergences were stable in upper pools, with significant similarity across late spring and summer months. Assemblages were seasonally variable in lower pools, with significant dissimilarity across spring, summer, and fall months. Few species in either zone were unique to spring or fall months. However, many summer species in the splash zone had a narrow emergence period occurring during calm weather following distinct increases in mean water temperature. Regardless of input of cold lake water to the lower zone, pools from both zones generally had corresponding temperature trends.

  15. Observation for really cold fragmentation of heavy nucleus

    International Nuclear Information System (INIS)

    Goverdovskij, A.A.; Ketlerov, V.V.; Mitrofanov, V.F.; Ostapenko, Yu.B.; Khryachkov, V.A.

    1998-01-01

    The results of the detailed study on mass-energy charged correlations of the thorium-232 fission fragments, produced by the 5 MeV neutrons are presented. The event of the thorium nucleus really cold fragmentation into tellurium-134 and strontium-99 at the basic quantum states is identified. It is shown that the whole reaction energy is exhausted by the motion kinetic energy of the fragments in the mutual field

  16. Burning Cold: Involvement of TRPA1 in Noxious Cold Sensation

    OpenAIRE

    Kwan, Kelvin Y.; Corey, David P.

    2009-01-01

    Soon after its discovery ten years ago, the ion channel TRPA1 was proposed as a sensor of noxious cold. Evidence for its activation by painfully cold temperatures (below ~15° C) has been mixed, however. Some groups found that cold elicits a nonselective conductance in cells expressing TRPA1; others found no activation, or argued that activation is an indirect effect of elevated \\(Ca^{ 2+}\\) . Sensory cells from the trigeminal and dorsal root ganglia that are activated by cold were sometimes c...

  17. Seasonal variation in AF-related admissions to a coronary care unit in a "hot" climate: fact or fiction?

    Science.gov (United States)

    Kiu, Andrew; Horowitz, John D; Stewart, Simon

    2004-01-01

    Seasonal variations in atrial fibrillation (AF)-related morbidity and mortality have been demonstrated in "cold" northern European climates, but there are few data describing such a phenomenon in a "hot" climate. To examine the pattern of AF-related admissions to a coronary care unit (CCU) in South Australia operating within a Mediterranean climate, and to determine potential differences according to mean daily temperatures. PATIENT COHORT AND METHODS: A total of 144 admissions to the CCU during the 30 hottest and coldest days (60 days in total) during the calendar year 2001 were analyzed in respect to the absolute number of admissions and the profile of those admitted during "hot" and "cold" days. Overall, there were significantly more admissions to the CCU on "cold" as opposed to "hot" days (90 vs 54 patients in 30 days, P < or = .001). Of the 24 patients found to be in AF on presentation to hospital, 18 (75%) were admitted on cold days (P < .05). Alternatively, during "hot" days, patients were more likely to be diagnosed with unstable angina rather than acute myocardial infarction (46% vs 30%, P = .07) with proportionately fewer patients in AF at the time (11% vs 20%, P = NS). These preliminary data suggest that the phenomenon of seasonal variations in AF-related morbidity extend beyond colder climates to hotter climates with sufficiently large relative (as opposed to absolute) changes in ambient temperatures during the year.

  18. Geographic and seasonal patterns and limits on the adaptive response to temperature of European Mytilus spp. and Macoma balthica populations

    NARCIS (Netherlands)

    Jansen, J.M.; Pronker, A.E.; Kube, S.; Sokolowski, A.; Sola, J.C.; Marquiegui, M.A.; Scheidek, D.; Bonga, W.S.; Wolowicz, M.; Hummel, H.

    2007-01-01

    Seasonal variations in seawater temperature require extensive metabolic acclimatization in cold-blooded organisms inhabiting the coastal waters of Europe. Given the energetic costs of acclimatization, differences in adaptive capacity to climatic conditions are to be expected among distinct

  19. Risk of hospitalization for fire-related burns during extreme cold weather.

    Science.gov (United States)

    Ayoub, Aimina; Kosatsky, Tom; Smargiassi, Audrey; Bilodeau-Bertrand, Marianne; Auger, Nathalie

    2017-10-01

    Environmental factors are important predictors of fires, but no study has examined the association between outdoor temperature and fire-related burn injuries. We sought to investigate the relationship between extremely cold outdoor temperatures and the risk of hospitalization for fire-related burns. We carried out a time-stratified case-crossover study of 2470 patients hospitalized for fire-related burn injuries during cold months between 1989 and 2014 in Quebec, Canada. The main exposure was the minimum outdoor temperature on the day of and the day before the burn. We computed odds ratios (OR) and 95% confidence intervals (CI) to evaluate the relationship between minimum temperature and fire-related burns, and assessed how associations varied across sex and age. Exposure to extreme cold temperature was associated with a significantly higher risk of hospitalization for fire-related burns. Compared with 0°C, exposure to a minimum temperature of -30°C was associated with an OR of 1.51 (95% CI 1.22-1.87) for hospitalization for fire-related burns. The associations were somewhat stronger for women, youth, and the elderly. Compared with 0°C, a minimum temperature of -30°C was associated with an OR for fire-related burn hospitalization of 1.65 for women (95% CI 1.13-2.40), 1.60 for age fire-related burns. Measures to prevent fires should be implemented prior to the winter season, and enhanced during extreme cold. Copyright © 2017 Elsevier Inc. All rights reserved.

  20. Observations of Cold Pool Properties during GoAmazon2014/5

    Science.gov (United States)

    Mayne, S. L.; Schumacher, C.; MacDonald, L.; Turner, D. D.

    2017-12-01

    Convectively generated cold pools are instrumental in both the development of the sub-cloud layer and the organization of deep convection. Despite this, analyses of cold pools in the tropics are constrained by a lack of observational data; insight into the phenomena therefore relies heavily on numerical models. GoAmazon2014/5, a 2-year DOE-sponsored field campaign centered on Manacapuru, Brazil in the central Amazon, provides a unique opportunity to characterize tropical cold pools and allows for the comparison of observational data with theoretical results from model cold pool simulations and parameterizations. This investigation analyzes radar, disdrometer, and profiler measurements at the DOE mobile facility site to study tropical cold pool characteristics. The Brazilian military (SIPAM) operational S-band radar in Manaus is used to provide a broad context of convective systems, while measurements from Parsivel disdrometers are used to assess drop-size distributions (DSDs) at the surface. A unique aspect of this research is the use of the Atmospheric Emitted Radiance Interferometer (AERI) instrument, which utilizes down-welling IR measurements to obtain vertical profiles of thermodynamic quantities such as temperature and water vapor in the lowest few km of the atmosphere. Combined with surface observations and sounding data, these datasets will result in a thorough investigation of the horizontal and vertical characteristics of cold pools over the tropical rain forest. Preliminary analyses of 20 events reveal a mean cold pool height of 220 m and a mean radius of approximately 8.5 km. The average cold pool experienced a temperature (specific humidity) decrease of approximately 1 K (0.4 g/kg) at the surface. The temperature decrease is consistent with modeling studies and limited observations from previous studies over the tropics. The small decrease in specific humidity is attributed to the high moisture content within the cold pools. AERI retrievals of

  1. Cold-Hearted or Cool-Headed: Physical Coldness Promotes Utilitarian Moral Judgment

    Directory of Open Access Journals (Sweden)

    Hiroko eNakamura

    2014-10-01

    Full Text Available In the current study, we examine the effect of physical coldness on personal moral dilemma judgment. Previous studies have indicated that utilitarian moral judgment—sacrificing a few people to achieve the greater good for others—was facilitated when: (1 participants suppressed an initial emotional response and deliberately thought about the utility of outcomes; (2 participants had a high-level construal mindset and focused on abstract goals (e.g., save many; or (3 there was a decreasing emotional response to sacrificing a few. In two experiments, we exposed participants to extreme cold or typical room temperature and then asked them to make personal moral dilemma judgments. The results of Experiment 1 indicated that coldness prompted utilitarian judgment, but the effect of coldness was independent from deliberate thought or abstract high-level construal mindset. As Experiment 2 revealed, coldness facilitated utilitarian judgment via reduced empathic feelings. Therefore, physical coldness did not affect the cool-headed deliberate process or the abstract high-level construal mindset. Rather, coldness biased people toward being cold-hearted, reduced empathetic concern about a sacrificed victim, and facilitated utilitarian moral judgments.

  2. Seasonal Cycle in German Daily Precipitation Extremes

    Directory of Open Access Journals (Sweden)

    Madlen Fischer

    2018-01-01

    Full Text Available The seasonal cycle of extreme precipitation in Germany is investigated by fitting statistical models to monthly maxima of daily precipitation sums for 2,865 rain gauges. The basis is a non-stationary generalized extreme value (GEV distribution variation of location and scale parameters. The negative log-likelihood serves as the forecast error for a cross validation to select adequate orders of the harmonic functions for each station. For nearly all gauges considered, the seasonal model is more appropriate to estimate return levels on a monthly scale than a stationary GEV used for individual months. The 100-year return-levels show the influence of cyclones in the western, and convective events in the eastern part of Germany. In addition to resolving the seasonality, we use a simulation study to show that annual return levels can be estimated more precisely from a monthly-resolved seasonal model than from a stationary model based on annual maxima.

  3. James Madison and a Shift in Precipitation Seasonality

    Science.gov (United States)

    Druckenbrod, D. L.; Mann, M. E.; Stahle, D. W.; Cleaveland, M. K.; Therrell, M. D.; Shugart, H. H.

    2001-12-01

    An eighteen-year meteorological diary and tree ring data from James Madison's Montpelier plantation provide a consistent reconstruction of early summer and prior fall rainfall for the 18th Century Virginia piedmont. The Madison meteorological diary suggests a seasonal shift in monthly rainfall towards an earlier wet season relative to 20th Century norms. Furthermore, dendroclimatic reconstructions of early summer and prior fall rainfall reflect this shift in the seasonality of summer rainfall. The most pronounced early summer drought during the Madison diary period is presented as a case study. This 1792 drought occurs during one of the strongest El Niño events on record and is highlighted in the correspondence of James Madison.

  4. Impacts of the seasonal distribution of rainfall on vegetation productivity across the Sahel

    Science.gov (United States)

    Zhang, Wenmin; Brandt, Martin; Tong, Xiaoye; Tian, Qingjiu; Fensholt, Rasmus

    2018-01-01

    Climate change in drylands has caused alterations in the seasonal distribution of rainfall including increased heavy-rainfall events, longer dry spells, and a shifted timing of the wet season. Yet the aboveground net primary productivity (ANPP) in drylands is usually explained by annual-rainfall sums, disregarding the influence of the seasonal distribution of rainfall. This study tested the importance of rainfall metrics in the wet season (onset and cessation of the wet season, number of rainy days, rainfall intensity, number of consecutive dry days, and heavy-rainfall events) for growing season ANPP. We focused on the Sahel and northern Sudanian region (100-800 mm yr-1) and applied daily satellite-based rainfall estimates (CHIRPS v2.0) and growing-season-integrated normalized difference vegetation index (NDVI; MODIS) as a proxy for ANPP over the study period: 2001-2015. Growing season ANPP in the arid zone (100-300 mm yr-1) was found to be rather insensitive to variations in the seasonal-rainfall metrics, whereas vegetation in the semi-arid zone (300-700 mm yr-1) was significantly impacted by most metrics, especially by the number of rainy days and timing (onset and cessation) of the wet season. We analysed critical breakpoints for all metrics to test if vegetation response to changes in a given rainfall metric surpasses a threshold beyond which vegetation functioning is significantly altered. It was shown that growing season ANPP was particularly negatively impacted after > 14 consecutive dry days and that a rainfall intensity of ˜ 13 mm day-1 was detected for optimum growing season ANPP. We conclude that the number of rainy days and the timing of the wet season are seasonal-rainfall metrics that are decisive for favourable vegetation growth in the semi-arid Sahel and need to be considered when modelling primary productivity from rainfall in the drylands of the Sahel and elsewhere.

  5. A new classification of large-scale climate regimes around the Tibetan Plateau based on seasonal circulation patterns

    Directory of Open Access Journals (Sweden)

    Xin-Gang Dai

    2017-03-01

    Full Text Available This study aims to develop a large-scale climate classification for investigating the characteristics of the climate regimes around the Tibetan Plateau based on seasonal precipitation, moisture transport and moisture divergence using in situ observations and ERA40 reanalysis data. The results indicate that the climate can be attributed to four regimes around the Plateau. They situate in East Asia, South Asia, Central Asia and the semi-arid zone in northern Central Asia throughout the dryland of northwestern China, in addition to the Köppen climate classification. There are different collocations of seasonal temperature and precipitation: 1 in phase for the East and South Asia monsoon regimes, 2 anti-phase for the Central Asia regime, 3 out-of-phase for the westerly regime. The seasonal precipitation concentrations are coupled with moisture divergence, i.e., moisture convergence coincides with the Asian monsoon zone and divergence appears over the Mediterranean-like arid climate region and westerly controlled area in the warm season, while it reverses course in the cold season. In addition, moisture divergence is associated with meridional moisture transport. The northward/southward moisture transport corresponds to moisture convergence/divergence, indicating that the wet and dry seasons are, to a great extent, dominated by meridional moisture transport in these regions. The climate mean southward transport results in the dry-cold season of the Asian monsoon zone and the dry-warm season, leading to desertification or land degradation in Central Asia and the westerly regime zone. The mean-wind moisture transport (MMT is the major contributor to total moisture transport, while persistent northward transient eddy moisture transport (TEMT plays a key role in dry season precipitation, especially in the Asian monsoon zone. The persistent TEMT divergence is an additional mechanism of the out-of-phase collocation in the westerly regime zone. In addition

  6. Characteristics and seasonal variations of precipitation phenomena at Syowa Station

    Directory of Open Access Journals (Sweden)

    Hiroyuki Konishi

    1997-03-01

    Full Text Available Long-term observations of precipitating clouds were carried out by a vertical pointing radar, PPI radar and a 37 GHz microwave radiometer at Syowa Station (69°00′S, 39°35′E, Antarctica in 1989. It is concluded from the observations that precipitation near Syowa Station, Antarctica is mainly brought by cloud vortices associated with extratropical cyclones which advance to high latitude while developing to a mature stage. The seasonal variations of clouds and precipitation were analyzed corresponding to the seasonal changes of air temperature and sea ice area. The occurrence frequencies of cloud vortices which brought snowfall to Syowa Station increased in the fall and spring seasons corresponding to activity of the circumpolar trough. However, the activities of cloud systems that bring precipitation weaken in spring when the sea ice area expands to low latitudes, because of less supply of heat and vapor. In 1989,the amount of precipitation in spring brought by a few snowfall events was as large as the amount of precipitation in fall brought by frequent snowfall events. Radar observations revealed that there were three abundant snowfall seasons at Syowa Station and the amount of snowfall was uniform in all seasons except summer. The amounts of precipitation in fall, winter and spring were 74,74 and 53mm respectively.

  7. Interannual Similarity in the Martian Atmosphere During the Dust Storm Season

    Science.gov (United States)

    Kass, D. M.; Kleinboehl, A.; McCleese, D. J.; Schofield, J. T.; Smith, M. D.

    2016-01-01

    We find that during the dusty season on Mars (southern spring and summer) of years without a global dust storm there are three large regional-scale dust storms. The storms are labeled A, B, and C in seasonal order. This classification is based on examining the zonal mean 50 Pa (approximately 25 km) daytime temperature retrievals from TES/MGS and MCS/MRO over 6 Mars Years. Regional-scale storms are defined as events where the temperature exceeds 200 K. Examining the MCS dust field at 50 Pa indicates that warming in the Southern Hemisphere is dominated by direct heating, while northern high latitude warming is a dynamical response. A storms are springtime planet encircling Southern Hemisphere events. B storms are southern polar events that begin near perihelion and last through the solstice. C storms are southern summertime events starting well after the end of the B storm. C storms show the most interannual variability.

  8. Should seasonal rainfall forecasts be used for flood preparedness?

    Directory of Open Access Journals (Sweden)

    E. Coughlan de Perez

    2017-09-01

    Full Text Available In light of strong encouragement for disaster managers to use climate services for flood preparation, we question whether seasonal rainfall forecasts should indeed be used as indicators of the likelihood of flooding. Here, we investigate the primary indicators of flooding at the seasonal timescale across sub-Saharan Africa. Given the sparsity of hydrological observations, we input bias-corrected reanalysis rainfall into the Global Flood Awareness System to identify seasonal indicators of floodiness. Results demonstrate that in some regions of western, central, and eastern Africa with typically wet climates, even a perfect tercile forecast of seasonal total rainfall would provide little to no indication of the seasonal likelihood of flooding. The number of extreme events within a season shows the highest correlations with floodiness consistently across regions. Otherwise, results vary across climate regimes: floodiness in arid regions in southern and eastern Africa shows the strongest correlations with seasonal average soil moisture and seasonal total rainfall. Floodiness in wetter climates of western and central Africa and Madagascar shows the strongest relationship with measures of the intensity of seasonal rainfall. Measures of rainfall patterns, such as the length of dry spells, are least related to seasonal floodiness across the continent. Ultimately, identifying the drivers of seasonal flooding can be used to improve forecast information for flood preparedness and to avoid misleading decision-makers.

  9. On the dynamics of an extreme rainfall event in northern India in 2013

    Indian Academy of Sciences (India)

    Anu Xavier

    2018-03-08

    Mar 8, 2018 ... the cold air to move southward. During the event, as the cold air moved south, it pushed the mid-latitude westerlies south of its normal position during summer monsoon and created a ... gradient between southern Asia and the Indian. Ocean develops due to increased solar heating over the Indian land area ...

  10. Warming up to cold fusion

    International Nuclear Information System (INIS)

    Storms, E.

    1994-01-01

    The idea that tabletop equipment at room temperature could produce nuclear fusion was widely rejected five years ago by the scientific community. Nevertheless, recent results from numerous labs show that a novel phenomena of some kind may indeed be occurring, though theorist are still groping for an explanation. Many aspects of the cold fusion effect are now reproducible if known procedures are used. Palladium, when reacted with enough deuterium, apparently converts to a special condition of matter in which various nuclear reactions--including deuterium-deuterium fusion--can occur despite the repulsive force of the two positive charged nuclei. These reactions can be made to proceed rapidly enough to produce measurable heat. Scientist have published several dozen models, ranging from highly analytical approaches to pictorial representations, to explain these events. Most theories address only the problem of overcoming the coulombic barrier--how it is possible for nuclei to overcome their natural repulsion for each other without an infusion of massive amounts of energy from the outside. None of the proposed explanations accounts for the full range of experimental observations. Nevertheless a workable theory is crucial if we ever hope to apply cold fusion

  11. Grooved cold moderator tests

    International Nuclear Information System (INIS)

    Inoue, K.; Kiyanagi, Y.; Iwasa, H.; Watanabe, N.; Ikeda, S.; Carpenter, J.M.; Ishikawa, Y.

    1983-01-01

    We performed some grooved cold moderator experiments for methane at 20 K by using the Hokkaido University linac to obtain information to be used in the planning of the KENS-I' project. Cold neutron gains, spatial distribution of emitted beams and time distribution of the neutrons in the grooved cold moderator were measured. Furthermore, we assessed the effects of the grooved cold moderator on the performances of the spectrometers presently installed at the KENS-I cold source. We concluded that the grooved cold moderator benefited appreciably the performances of the spectrometers

  12. Regional seesaw between the North Atlantic and Nordic Seas during the last glacial abrupt climate events

    Directory of Open Access Journals (Sweden)

    M. Wary

    2017-06-01

    Full Text Available Dansgaard–Oeschger oscillations constitute one of the most enigmatic features of the last glacial cycle. Their cold atmospheric phases have been commonly associated with cold sea-surface temperatures and expansion of sea ice in the North Atlantic and adjacent seas. Here, based on dinocyst analyses from the 48–30 ka interval of four sediment cores from the northern Northeast Atlantic and southern Norwegian Sea, we provide direct and quantitative evidence of a regional paradoxical seesaw pattern: cold Greenland and North Atlantic phases coincide with warmer sea-surface conditions and shorter seasonal sea-ice cover durations in the Norwegian Sea as compared to warm phases. Combined with additional palaeorecords and multi-model hosing simulations, our results suggest that during cold Greenland phases, reduced Atlantic meridional overturning circulation and cold North Atlantic sea-surface conditions were accompanied by the subsurface propagation of warm Atlantic waters that re-emerged in the Nordic Seas and provided moisture towards Greenland summit.

  13. Seasonal Changing Effect on Airflow and Pollutant Dispersion Characteristics in Urban Street Canyons

    Directory of Open Access Journals (Sweden)

    Jingliang Dong

    2017-02-01

    Full Text Available In this study, the effect of seasonal variation on air flow and pollutant dispersion characteristics was numerically investigated. A three-dimensional urban canopy model with unit aspect ratio (H/D = 1 was used to calculate surface temperature distribution in the street canyon. Four representative time events (1000 LST, 1300 LST, 1600 LST and 2000 LST during typical clear summer and winter days were selected to examine the air flow diurnal variation. The results revealed the seasonal variation significantly altered the street canyon microclimate. Compared with the street canyon surface temperature distribution in summer, the winter case showed a more evenly distributed surface temperature. In addition, the summer case showed greater daily temperature fluctuation than that of the winter case. Consequently, distinct pollutant dispersion patterns were observed between summer and winter scenarios, especially for the afternoon (1600 LST and night (2000 LST events. Among all studied time events, the pollutant removal performance of the morning (1000 LST and the night (2000 LST events were more sensitive to the seasonal variation. Lastly, limited natural ventilation performance was found during the summer morning and the winter night, which induced relatively high pollutant concentration along the pedestrian height level.

  14. Direct observations of seasonal exchange through the Bab el Mandab Strait

    Science.gov (United States)

    Murray, Stephen P.; Johns, William

    The exchange flow between the Red Sea and the Gulf of Aden-Indian Ocean through the Bab el Mandab Strait was measured continuously for 10 months, June 1995-March 1996. ADCP and temperature-salinity chain moorings allow an unprecedented look at the magnitude and seasonal evolution of the inflow layer from the Gulf of Aden, and the high salinity outflow layer from the Red Sea. The timing, structure, and evolution of the summer season mid-depth intrusion of cold, low salinity water into the Red Sea from the Gulf of Aden is measured for the complete intrusion cycle of 1995. We unexpectedly find the deep outflow still strong in June 1995, with speeds of 0.6 m/sec and transport of 0.4 Sv (1 Sv = 106 m³/sec). From July to mid-September, the deep outflow persists but is attenuated to speeds of 0.2 m/sec and transport of 0.05 Sv. The dominant summer feature, the cold low salinity intermediate layer intrusion, persists for 3 months, occupies 70% of the water column in the Strait and carries approximately 1.7 × 1012 m³ of cold nutrient-rich water into the Red Sea. The winter regime begins in mid-September, is fully developed by early November, and continues to the end of our first observation interval in March 1996. Speeds in the lower layer are 0.8-1.0 m/sec and 0.4-0.6 m/sec in the upper layer. At maximum exchange in mid-February, outflow transport reaches 0.7 Sv. Ubiquitous oscillations in current and salinity at synoptic and intraseasonal periods appear closely related to fluctuations in the along-channel wind forcing and perhaps to coastally-trapped waves.

  15. ENSO dynamics and seasonal cycle in the tropical Pacific as simulated by the ECHAM4/OPYC3 coupled general circulation model

    Energy Technology Data Exchange (ETDEWEB)

    Bacher, A. [Max-Planck-Institut fuer Meteorologie, Hamburg (Germany); Oberhuber, J.M. [Deutsches Klimarechenzentrum (DKRZ), Hamburg (Germany); Roeckner, E. [Max-Planck-Institut fuer Meteorologie, Hamburg (Germany)

    1996-07-01

    The new version of the atmospheric general circulation model, ECHAM4, at the Max Planck Institute for Meteorology, Hamburg, has been coupled to the OPYC3 isopycnic global ocean general circulation and sea ice model (Oberhuber 1993) in a multi-century present-day climate simulation. Nonseasonal constant flux adjustment for heat and freshwater was employed to ensure a long-term annual mean state close to present day climatology. This paper examines the simulated upper ocean seasonal cycle and interannual variability in the tropical Pacific for the first 100 years. The coupled model`s seasonal cycle of tropical Pacific SSTs is in good agreement with the observations with respect to both the warm pool variation and the Central and Eastern Pacific, with significant errors (up to -2 K) only in the cold tongue around April. The cold phase cold tongue extent and strength is as observed, and for this the heat flux adjustment does not play the decisive role; corrections beyond {+-}40 Wm{sup -2} are rare and only occupy small areas, such as near coasts. A well established south Pacific convergence zone is characteristic for the new AGCM version. Apart from extending the south-east trades seasonal maximum to midbasin, windstress pattern and strength are well captured. The subsurface structure is overall consistent with the observed, with a realistically sharp thermocline at about 150 m depth in the west and rising to the surface from 160 W to 100 W.

  16. Deep Super-SAGE transcriptomic analysis of cold acclimation in lentil (Lens culinaris Medik.).

    Science.gov (United States)

    Barrios, Abel; Caminero, Constantino; García, Pedro; Krezdorn, Nicolas; Hoffmeier, Klaus; Winter, Peter; Pérez de la Vega, Marcelino

    2017-06-30

    Frost is one of the main abiotic stresses limiting plant distribution and crop production. To cope with the stress, plants evolved adaptations known as cold acclimation or chilling tolerance to maximize frost tolerance. Cold acclimation is a progressive acquisition of freezing tolerance by plants subjected to low non-freezing temperatures which subsequently allows them to survive exposure to frost. Lentil is a cool season grain legume that is challenged by winter frost in some areas of its cultivation. To better understand the genetic base of frost tolerance differential gene expression in response to cold acclimation was investigated. Recombinant inbred lines (RILs) from the cross Precoz x WA8649041 were first classified as cold tolerant or cold susceptible according to their response to temperatures between -3 to -15 °C. Then, RILs from both extremes of the response curve were cold acclimated and the leaf transcriptomes of two bulks each of eight frost tolerant and seven cold susceptible RILs were investigated by Deep Super-SAGE transcriptome profiling. Thus, four RNA bulks were analysed: the acclimated susceptible, the acclimated tolerant and the respective controls (non-acclimated susceptible and non-acclimated tolerant). Approximately 16.5 million 26 nucleotide long Super-SAGE tags were sequenced in the four sets (between ~3 and 5.4 millions). In total, 133,077 different unitags, each representing a particular transcript isoform, were identified in these four sets. Tags which showed a significantly different abundance in any of the bulks (fold change ≥4.0 and a significant p-value <0.001) were selected and used to identify the corresponding lentil gene sequence. Three hundred of such lentil sequences were identified. Most of their known homologs coded for glycine-rich, cold and drought-regulated proteins, dormancy-associated proteins, proline-rich proteins (PRPs) and other membrane proteins. These were generally but not exclusively over-expressed in the

  17. Evolution of Indian Ocean biases in the summer monsoon season hindcasts from the Met Office Global Seasonal Forecasting System GloSea5

    Science.gov (United States)

    Chevuturi, A.; Turner, A. G.; Woolnough, S. J.

    2016-12-01

    In this study we investigate the development of biases in the Indian Ocean region in summer hindcasts of the UK Met Office coupled initialised global seasonal forecasting system, GloSea5-GC2. Previous work has demonstrated the rapid evolution of strong monsoon circulation biases over India from seasonal forecasts initialised in early May, together with coupled strong easterly wind biases on the equator. We analyse a set of three springtime start dates for the 20-year hindcast period (1992-2011) and fifteen total ensemble members for each year. We use comparisons with a variety of observations to test the rate of evolving mean-state biases in the Arabian Sea, over India, and over the equatorial Indian Ocean. Biases are all shown to develop rapidly, particularly for the circulation bias over India that is connected to convection. These circulation biases later reach the surface and lead to responses in Arabian Sea SST in accordance with coastal and Ekman upwelling processes. We also assess the evolution of radiation and turbulent heat fluxes at the surface. Meanwhile at the equator, easterly biases in surface winds are shown to develop rapidly, consistent with an SST pattern that is consistent with positive-Indian Ocean dipole mean state conditions (warm western equatorial Indian Ocean, cold east). This bias develops consistent with coupled ocean-atmosphere exchanges and Bjerknes feedback. We hypothesize that lower tropospheric easterly wind biases developing in the equatorial region originate from the surface, and also that signals of the cold bias in the eastern equatorial Indian Ocean propagate to the Bay of Bengal via coastal Kelvin waves. Earlier work has shown the utility of wind-stress corrections in the Indian Ocean for correcting the easterly winds bias there and ultimately improving the evolution of the Indian Ocean Dipole. We identify and test this wind-stress correction technique in case study years from the hindcast period to see their impact on seasonal

  18. Nitrogen and phosphorus transport between Fourleague Bay, LA, and the Gulf of Mexico: The role of winter cold fronts and Atchafalaya River discharge

    Science.gov (United States)

    Perez, B.C.; Day, J.W.; Justic, D.; Twilley, R.R.

    2003-01-01

    Nutrient fluxes were measured between Fourleague Bay, a shallow Louisiana estuary, and the Gulf of Mexico every 3 h between February 1 and April 30, 1994 to determine how high velocity winds associated with cold fronts and peak Atchafalaya River discharge influenced transport. Net water fluxes were ebb-dominated throughout the study because of wind forcing and high volumes of water entering the northern Bay from the Atchafalaya River. Flushing time of the Bay averaged winds with approximately 56% of the volume of the Bay exported to the Gulf in 1 day during the strongest flushing event. Higher nitrate + nitrite (NO2+ NO3), total nitrogen (TN), and total phosphorus (TP) concentrations were indicative of Atchafalaya River input and fluxes were greater when influenced by high velocity northerly winds associated with frontal passage. Net exports of NO2 + NO3, TN, and TP were 43.5, 98.5, and 13.6 g s-1, respectively, for the 89-day study. An average of 10.6 g s-1 of ammonium (NH4) was exported to the Gulf over the study; however, concentrations were lower when associated with riverine influence and wind-driven exports suggesting the importance of biological processes. Phosphate (PO4) fluxes were nearly balanced over the study with fairly stable concentrations indicating a well-buffered system. The results indicate that the high energy subsidy provided by natural pulsing events such as atmospheric cold fronts and seasonal river discharge are efficient mechanisms of nutrient delivery to adjacent wetlands and nearshore coastal ecosystems and are important in maintaining coastal sustainability. ?? 2003 Elsevier Ltd. All rights reserved.

  19. Seasonal dynamics of bacterial biomass and production in a coastal arctic ecosystem: Franklin Bay, western Canadian Arctic

    Science.gov (United States)

    Garneau, Marie-Ã. Ve; Roy, SéBastien; Lovejoy, Connie; Gratton, Yves; Vincent, Warwick F.

    2008-07-01

    The Canadian Arctic Shelf Exchange Study (CASES) included the overwintering deployment of a research platform in Franklin Bay (70°N, 126°W) and provided a unique seasonal record of bacterial dynamics in a coastal region of the Arctic Ocean. Our objectives were (1) to relate seasonal bacterial abundance (BA) and production (BP) to physico-chemical characteristics and (2) to quantify the annual bacterial carbon flux. BA was estimated by epifluorescence microscopy and BP was estimated from 3H-leucine and 3H-thymidine assays. Mean BA values for the water column ranged from 1.0 (December) to 6.8 × 105 cells mL-1 (July). Integral BP varied from 1 (February) to 80 mg C m-2 d-1 (July). During winter-spring, BP was uncorrelated with chlorophyll a (Chl a), but these variables were significantly correlated during summer-autumn (rs = 0.68, p winter, late winter-late spring, and summer. A baseline level of BB and BP was maintained throughout late winter-late spring despite the persistent cold and darkness, with irregular fluctuations that may be related to hydrodynamic events. During this period, BP rates were correlated with colored dissolved organic matter (CDOM) but not Chl a (rs BP.CDOM∣Chl a = 0.20, p < 0.05, N = 176). Annual BP was estimated as 6 g C m-2 a-1, implying a total BP of 4.8 × 1010 g C a-1 for the Franklin Bay region. These results show that bacterial processes continue throughout all seasons and make a large contribution to the total biological carbon flux in this coastal arctic ecosystem.

  20. Covariability of seasonal temperature and precipitation over the Iberian Peninsula in high-resolution regional climate simulations (1001-2099)

    Science.gov (United States)

    Fernández-Montes, S.; Gómez-Navarro, J. J.; Rodrigo, F. S.; García-Valero, J. A.; Montávez, J. P.

    2017-04-01

    Precipitation and surface temperature are interdependent variables, both as a response to atmospheric dynamics and due to intrinsic thermodynamic relationships and feedbacks between them. This study analyzes the covariability of seasonal temperature (T) and precipitation (P) across the Iberian Peninsula (IP) using regional climate paleosimulations for the period 1001-1990, driven by reconstructions of external forcings. Future climate (1990-2099) was simulated according to SRES scenarios A2 and B2. These simulations enable exploring, at high spatial resolution, robust and physically consistent relationships. In winter, positive P-T correlations dominate west-central IP (Pearson correlation coefficient ρ = + 0.43, for 1001-1990), due to prevalent cold-dry and warm-wet conditions, while this relationship weakens and become negative towards mountainous, northern and eastern regions. In autumn, negative correlations appear in similar regions as in winter, whereas for summer they extend also to the N/NW of the IP. In spring, the whole IP depicts significant negative correlations, strongest for eastern regions (ρ = - 0.51). This is due to prevalent frequency of warm-dry and cold-wet modes in these regions and seasons. At the temporal scale, regional correlation series between seasonal anomalies of temperature and precipitation (assessed in 31 years running windows in 1001-1990) show very large multidecadal variability. For winter and spring, periodicities of about 50-60 years arise. The frequency of warm-dry and cold-wet modes appears correlated with the North Atlantic Oscillation (NAO), explaining mainly co-variability changes in spring. For winter and some regions in autumn, maximum and minimum P-T correlations appear in periods with enhanced meridional or easterly circulation (low or high pressure anomalies in the Mediterranean and Europe). In spring and summer, the Atlantic Multidecadal Oscillation shows some fingerprint on the frequency of warm/cold modes. For

  1. Extreme hydrometeorological events in the Peruvian Central Andes during austral summer and their relationship with the large-scale circulation

    Science.gov (United States)

    Sulca, Juan C.

    In this Master's dissertation, atmospheric circulation patterns associated with extreme hydrometeorological events in the Mantaro Basin, Peruvian Central Andes, and their teleconnections during the austral summer (December-January-February-March) are addressed. Extreme rainfall events in the Mantaro basin are related to variations of the large-scale circulation as indicated by the changing strength of the Bolivian High-Nordeste Low (BH-NL) system. Dry (wet) spells are associated with a weakening (strengthening) of the BH-NL system and reduced (enhanced) influx of moist air from the lowlands to the east due to strengthened westerly (easterly) wind anomalies at mid- and upper-tropospheric levels. At the same time extreme rainfall events of the opposite sign occur over northeastern Brazil (NEB) due to enhanced (inhibited) convective activity in conjunction with a strengthened (weakened) Nordeste Low. Cold episodes in the Mantaro Basin are grouped in three types: weak, strong and extraordinary cold episodes. Weak and strong cold episodes in the MB are mainly associated with a weakening of the BH-NL system due to tropical-extratropical interactions. Both types of cold episodes are associated with westerly wind anomalies at mid- and upper-tropospheric levels aloft the Peruvian Central Andes, which inhibit the influx of humid air masses from the lowlands to the east and hence limit the potential for development of convective cloud cover. The resulting clear sky conditions cause nighttime temperatures to drop, leading to cold extremes below the 10-percentile. Extraordinary cold episodes in the MB are associated with cold and dry polar air advection at all tropospheric levels toward the central Peruvian Andes. Therefore, weak and strong cold episodes in the MB appear to be caused by radiative cooling associated with reduced cloudiness, rather than cold air advection, while the latter plays an important role for extraordinary cold episodes only.

  2. The Effect of Cold Showering on Health and Work: A Randomized Controlled Trial

    Science.gov (United States)

    Sierevelt, Inger N.; van der Heijden, Bas C. J. M.; Dijkgraaf, Marcel G.; Frings-Dresen, Monique H. W.

    2016-01-01

    Purpose The aim of this study was to determine the cumulative effect of a routine (hot-to-) cold shower on sickness, quality of life and work productivity. Methods Between January and March 2015, 3018 participants between 18 and 65 years without severe comorbidity and no routine experience of cold showering were randomized (1:1:1:1) to a (hot-to-) cold shower for 30, 60, 90 seconds or a control group during 30 consecutive days followed by 60 days of showering cold at their own discretion for the intervention groups. The primary outcome was illness days and related sickness absence from work. Secondary outcomes were quality of life, work productivity, anxiety, thermal sensation and adverse reactions. Results 79% of participants in the interventions groups completed the 30 consecutive days protocol. A negative binomial regression model showed a 29% reduction in sickness absence for (hot-to-) cold shower regimen compared to the control group (incident rate ratio: 0.71, P = 0.003). For illness days there was no significant group effect. No related serious advents events were reported. Conclusion A routine (hot-to-) cold shower resulted in a statistical reduction of self-reported sickness absence but not illness days in adults without severe comorbidity. Trial Registration Netherlands National Trial Register NTR5183 PMID:27631616

  3. Constraining Parameter Uncertainty in Simulations of Water and Heat Dynamics in Seasonally Frozen Soil Using Limited Observed Data

    Directory of Open Access Journals (Sweden)

    Mousong Wu

    2016-02-01

    Full Text Available Water and energy processes in frozen soils are important for better understanding hydrologic processes and water resources management in cold regions. To investigate the water and energy balance in seasonally frozen soils, CoupModel combined with the generalized likelihood uncertainty estimation (GLUE method was used. Simulation work on water and heat processes in frozen soil in northern China during the 2012/2013 winter was conducted. Ensemble simulations through the Monte Carlo sampling method were generated for uncertainty analysis. Behavioral simulations were selected based on combinations of multiple model performance index criteria with respect to simulated soil water and temperature at four depths (5 cm, 15 cm, 25 cm, and 35 cm. Posterior distributions for parameters related to soil hydraulic, radiation processes, and heat transport indicated that uncertainties in both input and model structures could influence model performance in modeling water and heat processes in seasonally frozen soils. Seasonal courses in water and energy partitioning were obvious during the winter. Within the day-cycle, soil evaporation/condensation and energy distributions were well captured and clarified as an important phenomenon in the dynamics of the energy balance system. The combination of the CoupModel simulations with the uncertainty-based calibration method provides a way of understanding the seasonal courses of hydrology and energy processes in cold regions with limited data. Additional measurements may be used to further reduce the uncertainty of regulating factors during the different stages of freezing–thawing.

  4. (When and where) Do extreme climate events trigger extreme ecosystem responses? - Development and initial results of a holistic analysis framework

    Science.gov (United States)

    Hauber, Eva K.; Donner, Reik V.

    2015-04-01

    In the context of ongoing climate change, extremes are likely to increase in magnitude and frequency. One of the most important consequences of these changes is that the associated ecological risks and impacts are potentially rising as well. In order to better anticipate and understand these impacts, it therefore becomes more and more crucial to understand the general connection between climate extremes and the response and functionality of ecosystems. Among other region of the world, Europe presents an excellent test case for studies concerning the interaction between climate and biosphere, since it lies in the transition region between cold polar and warm tropical air masses and thus covers a great variety of different climatic zones and associated terrestrial ecosystems. The large temperature differences across the continent make this region particularly interesting for investigating the effects of climate change on biosphere-climate interactions. However, previously used methods for defining an extreme event typically disregard the necessity of taking seasonality as well as seasonal variance appropriately into account. Furthermore, most studies have focused on the impacts of individual extreme events instead of considering a whole inventory of extremes with their respective spatio-temporal extents. In order to overcome the aforementioned research gaps, this work introduces a new approach to studying climate-biosphere interactions associated with extreme events, which comprises three consecutive steps: (1) Since Europe exhibits climatic conditions characterized by marked seasonality, a novel method is developed to define extreme events taking into account the seasonality in all quantiles of the probability distribution of the respective variable of interest. This is achieved by considering kernel density estimates individually for each observation date during the year, including the properly weighted information from adjacent dates. By this procedure, we obtain

  5. Drivers of the Seasonal Carbon Cycle in the Coastal Gulf of Alaska

    Science.gov (United States)

    Pilcher, D.; Siedlecki, S. A.; Hermann, A. J.; Coyle, K. O.; Mathis, J. T.

    2016-02-01

    The Coastal Gulf of Alaska serves as a significant carbon sink annually, but varies seasonally from net carbon efflux in winter, to net carbon uptake from spring through fall. This significant uptake of anthropogenic CO2 combined with the naturally cold, low calcium carbonate surface waters is expected to accelerate ocean acidification. Observational evidence has already detected subsurface aragonite undersaturation, likely resulting from carbon remineralization of sinking organic matter. Other processes such as storm-induced vertical mixing, glacial runoff, temperature change, and nutrient supply can further modify the carbon cycle. Improving knowledge of these seasonal processes is critical for the region's fisheries that provide substantial ecosystem services and can be adversely impacted by sub-optimal aragonite saturation conditions. We use a regional model of the Coastal Gulf of Alaska coupled to an ecosystem model with full carbonate chemistry to investigate the physical and biogeochemical mechanisms that drive the seasonal carbon cycle. Boundary conditions are set from the coarser Northeast Pacific model, with alkalinity and carbon concentrations determined from empirical relationships with salinity. Model output from a 2009 hindcast simulation is compared to observations of alkalinity and dissolved inorganic carbon concentrations for model verification and to elucidate seasonal mechanisms.

  6. Cold acclimation increases cold tolerance independently of diapause programing in the bean bug, Riptortus pedestris.

    Science.gov (United States)

    Rozsypal, J; Moos, M; Goto, S G

    2017-10-17

    The bean bug (Riptortus pedestris) is a pest of soybeans and other legumes in Japan and other Asian countries. It enters a facultative adult diapause on exposure to short days. While photoperiodism and diapause are well understood in R. pedestris, knowledge of cold tolerance is very limited, as is information on the effect of diapause on cold tolerance. We examined the effect of photoperiod, cold acclimation, and feeding status on cold tolerance in R. pedestris. We found that cold acclimation significantly increased survival at -10°C in both long- and short-day adult R. pedestris. Since the difference in cold survival between long- and short-day cold-acclimated groups was only marginal, we conclude that entering diapause is not crucial for R. pedestris to successfully pass through cold acclimation and become cold tolerant. We observed similar effects in 5th instar nymphs, with both long- and short-day cold-acclimated groups surviving longer cold exposures compared with non-acclimated groups. Starvation, which was tested only in adult bugs, had only a negligible and negative impact on cold survival. Although cold tolerance significantly increased with cold acclimation in adult bugs, supercooling capacity unexpectedly decreased. Our results suggest that changes in supercooling capacity as well as in water content are unrelated to cold tolerance in R. pedestris. An analysis of metabolites revealed differences between the treatments, and while several metabolites markedly increased with cold acclimation, their concentrations were too low to have a significant effect on cold tolerance.

  7. Different Stratospheric Polar Vortex States linked to Cold-Spells in North America and Northern Eurasia

    Science.gov (United States)

    Kretschmer, M.; Cohen, J. L.; Runge, J.; Coumou, D.

    2017-12-01

    The stratospheric polar vortex in boreal winter can influence the tropospheric circulation and thereby surface weather in the mid-latitudes. Weak states of the vortex, e.g. associated with Sudden Stratospheric Warmings (SSWs), often precede a negative phase of the North Atlantic Oscillation (NAO), and thus increase the risk of mid-latitude cold-spells especially over Eurasia. Here we show using cluster analysis that next to the well-documented relationship between a zonally symmetric disturbed vortex and a negative NAO, there exists a zonally asymmetric pattern linked to a negative Western Pacific Oscillation (WPO) and cold-spells in the northeastern US, like for example observed in February 2014. The latter is more synoptic in time-scale but occurs more frequently than SSWs. A causal effect network (CEN) approach gives insights into the underlying physical pathways and time-lags showing that high-pressure around Greenland leads to vertical wave activity over eastern Siberia leading to downward propagating waves over Alaska and high pressure over the North Pacific. Moreover, composites propose that a rather strong mid-stratospheric vortex seems to be favorable for this zonally asymmetric and reflective mechanism. Overall, the mutual relationship between stratospheric circulation and high-latitude blocking in both the Pacific and Atlantic Oceans is complex and involves mechanisms operating at different time-scales. Our results suggest that the stratospheric influence on winter circulation should not exclusively be analyzed in terms of a downward propagating Northern Annular Mode (NAM) signal and SSWs. In particular when studying the stratospheric impacts on North American temperature it is crucial to also consider the more transient and zonally asymmetric events which might help to improve seasonal winter predictions for this region.

  8. Enhanced production of nitric oxide in A549 cells through activation of TRPA1 ion channel by cold stress.

    Science.gov (United States)

    Sun, Wenwu; Wang, Zhonghua; Cao, Jianping; Wang, Xu; Han, Yaling; Ma, Zhuang

    2014-08-31

    The respiratory epithelium is exposed to the external environment, and inhalation of cold air is common during the season of winter. In addition, the lung is a major source of nitric oxide (NO). However, the effect of cold stress on the production of NO is still unclear. In the present work, We measured the change of NO in single cell with DACF-DA and the change in cytosolic Ca(2+) concentration ([Ca(2+)]c) in A549 cell. We observed that cold stress (from 20 °C to 5 °C) induced an increase of NO in A549 cell, which was completely abolished by applying an extracellular Ca(2+) free medium. Further experiments showed that cold-sensing transient receptor potential subfamily member 1 (TRPA1) channel agonist (allyl isothiocyanate, AITC) increased the production of NO and the level of [Ca(2+)]c in A549 cell. Additionally, TRPA1 inhibitor, Ruthenium red (RR) and camphor, significantly blocked the enhanced production of NO and the rise of [Ca(2+)]c induced by AITC or cold stimulation, respectively. Taken together, these data indicated that cold-induced TRPA1 activation was responsible for the enhanced production of NO in A549 cell. Copyright © 2014 Elsevier Inc. All rights reserved.

  9. Autochthonous Chikungunya Transmission and Extreme Climate Events in Southern France.

    Science.gov (United States)

    Roiz, David; Boussès, Philippe; Simard, Frédéric; Paupy, Christophe; Fontenille, Didier

    2015-06-01

    Extreme precipitation events are increasing as a result of ongoing global warming, but controversy surrounds the relationship between flooding and mosquito-borne diseases. A common view among the scientific community and public health officers is that heavy rainfalls have a flushing effect on breeding sites, which negatively affects vector populations, thereby diminishing disease transmission. During 2014 in Montpellier, France, there were at least 11 autochthonous cases of chikungunya caused by the invasive tiger mosquito Aedes albopictus in the vicinity of an imported case. We show that an extreme rainfall event increased and extended the abundance of the disease vector Ae. albopictus, hence the period of autochthonous transmission of chikungunya. We report results from close monitoring of the adult and egg population of the chikungunya vector Ae. albopictus through weekly sampling over the entire mosquito breeding season, which revealed an unexpected pattern. Statistical analysis of the seasonal dynamics of female abundance in relation to climatic factors showed that these relationships changed after the heavy rainfall event. Before the inundations, accumulated temperatures are the most important variable predicting Ae. albopictus seasonal dynamics. However, after the inundations, accumulated rainfall over the 4 weeks prior to capture predicts the seasonal dynamics of this species and extension of the transmission period. Our empirical data suggests that heavy rainfall events did increase the risk of arbovirus transmission in Southern France in 2014 by favouring a rapid rise in abundance of vector mosquitoes. Further studies should now confirm these results in different ecological contexts, so that the impact of global change and extreme climatic events on mosquito population dynamics and the risk of disease transmission can be adequately understood.

  10. Seasonal patterns of reserve and soluble carbohydrates in mature sugar maple (Acer saccharum)

    Science.gov (United States)

    B.L. Wong; K.L. Baggett; A.H. Rye

    2003-01-01

    Sugar maple (Acer saccharum Marsh.) trees exhibit seasonal patterns of production, accumulation, and utilization of nonstructural carbohydrates that are closely correlated with phenological events and (or) physiological processes. The simultaneous seasonal patterns of both reserve and soluble carbohydrates in the leaves, twigs, branches, and trunks of healthy mature...

  11. The I.A.G. / A.I.G. SEDIBUD (Sediment Budgets in Cold Environments) Programme: Current and future activities

    Science.gov (United States)

    Beylich, Achim A.; Lamoureux, Scott; Decaulne, Armelle

    2013-04-01

    Projected climate change in cold regions is expected to alter melt season duration and intensity, along with the number of extreme rainfall events, total annual precipitation and the balance between snowfall and rainfall. Similarly, changes to the thermal balance are expected to reduce the extent of permafrost and seasonal ground frost and increase active layer depths. These effects will undoubtedly change surface environments in cold regions and alter the fluxes of sediments, nutrients and solutes, but the absence of quantitative data and coordinated geomorphic process monitoring and analysis to understand the sensitivity of the Earth surface environment is acute in cold climate environments. The International Association of Geomorphologists (I.A.G. / A.I.G. ) SEDIBUD (Sediment Budgets in Cold Environments) Programme was formed in 2005 to address this existing key knowledge gap. SEDIBUD currently has about 400 members worldwide and the Steering Committee of this international programme is composed of ten scientists from eight different countries: Achim A. Beylich (Chair) (Norway), Armelle Decaulne (Secretary) (France), John C. Dixon (USA), Scott F. Lamoureux (Vice-Chair) (Canada), John F. Orwin (Canada), Jan-Christoph Otto (Austria), Irina Overeem (USA), Thorsteinn Sæmundsson (Iceland), Jeff Warburton (UK) and Zbigniew Zwolinski (Poland). The central research question of this global group of scientists is to: Assess and model the contemporary sedimentary fluxes in cold climates, with emphasis on both particulate and dissolved components. Initially formed as European Science Foundation (ESF) Network SEDIFLUX (Sedimentary Source-to-Sink Fluxes in Cold Environments) (2004 - ), SEDIBUD has further expanded to a global group of researchers with field research sites located in polar and alpine regions in the northern and southern hemisphere. Research carried out at each of the close to 50 defined SEDIBUD key test sites varies by programme, logistics and available

  12. Large-scale evaluation of pea (Pisum sativum L.) germplasm for cold tolerance in the open field during winter in Qingdao.

    Science.gov (United States)

    As a cool season crop, pea (Pisum sativum L.) can tolerate frost at the vegetative stage but has yield loss when freezing stress occurs at reproductive stage. Cold tolerance improvement of pea varieties is important for the stable yield and the expansion of winter pea planting area. Under the natura...

  13. Seasonal isotope hydrology of a coffee agroforestry watershed in Costa Rica

    Science.gov (United States)

    Welsh Unwala, K.; Boll, J.; Roupsard, O.

    2014-12-01

    Improved information of seasonal variations in watershed hydrology in the tropics can strengthen models and understanding of hydrology of these areas. Seasonality in the tropics produces rainy seasons versus dry seasons, leading to different hydrologic and water quality processes throughout the year. We questioned whether stable isotopes in water can be used to trace the seasonality in this region, despite experiencing a "drier" season, such as in a Tropical Humid location. This study examines the fluctuations of stable isotope compositions (δ18O and δD) in water balance components in a small (deep groundwater system contributes significantly to baseflow, although a shallow, spring-driven system also contributes to stream water within the watershed. During storm events, precipitation contributes to stormflow in the short-term, confirming the role of superficial runoff. These results indicate that isotopes are helpful to partition the water balance even in a Tropical Humid situation where the rainfall seasonality is weak.

  14. Estimates of eddy turbulence consistent with seasonal variations of atomic oxygen and its possible role in the seasonal cycle of mesopause temperature

    Directory of Open Access Journals (Sweden)

    M. N. Vlasov

    2010-11-01

    Full Text Available According to current understanding, adiabatic cooling and heating induced by the meridional circulation driven by gravity waves is the major process for the cold summer and warm winter polar upper mesosphere. However, our calculations show that the upward/downward motion needed for adiabatic cooling/heating of the summer/winter polar mesopause simultaneously induces a seasonal variation in both the O maximum density and the altitude of the [O] peak that is opposite to the observed variables generalized by the MSISE-90 model. It is usually accepted that eddy turbulence can produce the [O] seasonal variations. Using this approach, we can infer the eddy diffusion coefficient for the different seasons. Taking these results and experimental data on the eddy diffusion coefficient, we consider in detail and estimate the heating and cooling caused by eddy turbulence in the summer and winter polar upper mesosphere. The seasonal variations of these processes are similar to the seasonal variations of the temperature and mesopause. These results lead to the conclusion that heating/cooling by eddy turbulence is an important component in the energy budget and that adiabatic cooling/heating induced by upward/downward motion cannot dominate in the mesopause region. Our study shows that the impact of the dynamic process, induced by gravity waves, on [O] distributions must be included in models of thermal balance in the upper mesosphere and lower thermosphere (MLT for a consistent description because (a the [O] distribution is very sensitive to dynamic processes, and (b atomic oxygen plays a very important role in chemical heating and infrared cooling in the MLT. To our knowledge, this is the first attempt to consider this aspect of the problem.

  15. Comparison of Ant Community Diversity and Functional Group Composition Associated to Land Use Change in a Seasonally Dry Oak Forest.

    Science.gov (United States)

    Cuautle, M; Vergara, C H; Badano, E I

    2016-04-01

    Ants have been used to assess land use conversion, because they reflect environmental change, and their response to these changes have been useful in the identification of bioindicators. We evaluated ant diversity and composition associated to different land use change in a temperate forest (above 2000 m asl) in Mexico. The study was carried out in "Flor del Bosque" Park a vegetation mosaic of native Oak Forests and introduced Eucalyptus and grasslands. Species richness, dominance and diversity rarefaction curves, based on ant morphospecies and functional groups, were constructed and compared among the three vegetation types, for the rainy and the dry seasons of 2008-2009. Jaccard and Sorensen incidence-based indices were calculated to obtain similarity values among all the habitats. The Oak Forest was a rich dominant community, both in species and functional groups; the Eucalyptus plantation was diverse with low dominance. The most seasonality habitat was the grassland, with low species and high functional group diversity during the dry seasons, but the reverse pattern during the wet season. The Oak Forest was more similar to the Eucalyptus plantation than to the grassland, particularly during the dry season. Oak Forests are dominated by Cold Climate Specialists, specifically Prenolepis imparis (Say). The Eucalyptus and the grassland are characterized by generalized Myrmicinae, as Pheidole spp. and Monomorium ebenium (Forel). The conservation of the native Oak Forest is primordial for the maintenance of Cold Climate Specialist ant communities. The microclimatic conditions in this forest, probably, prevented the invasion by opportunistic species.

  16. Cold formability of steels

    International Nuclear Information System (INIS)

    Lafond, G.; Leclerq, G.; Moliexe, F.; Namdar, R.; Roesch, L.; Sanz, G.

    1977-01-01

    This work was essentially aimed to the study of the following three questions. Is it possible to assess the cold formability of steels using simple material properties as criteria. What values of mechanical properties can one expect to reach in cold formed parts. Are there simple ways of characterizing the speroidization treatments carried out on steels before cold forming operations. The present report describes the results obtained during this investigation. It is logically divided into three separate parts. Experimental study of cold formability in wire drawing. Influence of metallurgical variables on mechanical properties of high carbon cold drawn wires. Contribution to the study of characterization methods of cold forming steels subjected to a spheroidization heat treatment

  17. Human whole body cold adaptation.

    Science.gov (United States)

    Daanen, Hein A M; Van Marken Lichtenbelt, Wouter D

    2016-01-01

    Reviews on whole body human cold adaptation generally do not distinguish between population studies and dedicated acclimation studies, leading to confusing results. Population studies show that indigenous black Africans have reduced shivering thermogenesis in the cold and poor cold induced vasodilation in fingers and toes compared to Caucasians and Inuit. About 40,000 y after humans left Africa, natives in cold terrestrial areas seems to have developed not only behavioral adaptations, but also physiological adaptations to cold. Dedicated studies show that repeated whole body exposure of individual volunteers, mainly Caucasians, to severe cold results in reduced cold sensation but no major physiological changes. Repeated cold water immersion seems to slightly reduce metabolic heat production, while repeated exposure to milder cold conditions shows some increase in metabolic heat production, in particular non-shivering thermogenesis. In conclusion, human cold adaptation in the form of increased metabolism and insulation seems to have occurred during recent evolution in populations, but cannot be developed during a lifetime in cold conditions as encountered in temperate and arctic regions. Therefore, we mainly depend on our behavioral skills to live in and survive the cold.

  18. Seasonal temperature extremes in Potsdam

    Science.gov (United States)

    Kundzewicz, Zbigniew; Huang, Shaochun

    2010-12-01

    The awareness of global warming is well established and results from the observations made on thousands of stations. This paper complements the large-scale results by examining a long time-series of high-quality temperature data from the Secular Meteorological Station in Potsdam, where observation records over the last 117 years, i.e., from January 1893 are available. Tendencies of change in seasonal temperature-related climate extremes are demonstrated. "Cold" extremes have become less frequent and less severe than in the past, while "warm" extremes have become more frequent and more severe. Moreover, the interval of the occurrence of frost has been decreasing, while the interval of the occurrence of hot days has been increasing. However, many changes are not statistically significant, since the variability of temperature indices at the Potsdam station has been very strong.

  19. Monitoring Grassland Tourist Season of Inner Mongolia, China Using Remote Sensing Data

    Directory of Open Access Journals (Sweden)

    Quansheng Ge

    2014-01-01

    Full Text Available Phenology-driven events, such as spring wildflower displays or fall tree colour, are generally appreciated by tourists for centuries around the world. Monitoring when tourist seasons occur using satellite data has been an area of growing research interest in recent decades. In this paper, a valid methodology for detecting the grassland tourist season using remote sensing data was presented. On average, the beginning, the best, and the end of grassland tourist season of Inner Mongolia, China, occur in late June (±30 days, early July (±30 days, and late July (±50 days, respectively. In south region, the grassland tourist season appeared relatively late. The length of the grassland tourist season is about 90 days with strong spatial trend. South areas exhibit longer tourist season.

  20. Bjerknes' hypothesis on the coldness during AD 1790-1820 revisited

    Energy Technology Data Exchange (ETDEWEB)

    Schrier, G. van der [UEA, Climatic Research Unit, Norwich (United Kingdom); Barkmeijer, J. [Royal Netherlands Meteorological Institute (KNMI), De Bilt (Netherlands)

    2005-03-01

    The aim of this paper is to re-examine and quantify a hypothesis first put forward by J. Bjerknes concerning the anomalous coldness during the AD 1790-1820 period in western Europe. Central to Bjerknes' hypothesis is an anomalous interaction between ocean and atmosphere studied here using an ocean-atmosphere coupled climate model of intermediate complexity. A reconstruction of the sea-level pressure pattern over the North Atlantic sector averaged over the period 1790-1820 is assimilated in this model, using a recently developed technique which has not been applied to paleoclimatic modelling before. This technique ensures that averaged over the simulation the reconstructed pattern is retrieved whilst leaving atmospheric and climatic variability to develop freely. In accordance with Bjerknes' hypothesis, the model results show anomalous southward advection of polar waters into the northeastern North Atlantic in the winter season, lowering the sea-surface temperatures (SSTs) there with 0.3-1.0 C. This SST anomaly is persistent into the summer season. A decrease in western European winter surface air temperatures is found which can be related almost completely to advection of cold polar air. The decrease in summer surface air temperatures is related to a combination of low SSTs and anomalous atmospheric circulation. The modelled winter and summer temperatures in Europe compare favourably with reconstructed temperatures. Enhanced baroclinicity at the Atlantic seaboard and over Baffin Island is observed along with more variability in the position of the North Atlantic storm tracks. The zone of peak winter storm frequency is drawn to the European mid-latitudes. (orig.)

  1. Visualizing the uncertainty in the relationship between seasonal average climate and malaria risk.

    Science.gov (United States)

    MacLeod, D A; Morse, A P

    2014-12-02

    Around $1.6 billion per year is spent financing anti-malaria initiatives, and though malaria morbidity is falling, the impact of annual epidemics remains significant. Whilst malaria risk may increase with climate change, projections are highly uncertain and to sidestep this intractable uncertainty, adaptation efforts should improve societal ability to anticipate and mitigate individual events. Anticipation of climate-related events is made possible by seasonal climate forecasting, from which warnings of anomalous seasonal average temperature and rainfall, months in advance are possible. Seasonal climate hindcasts have been used to drive climate-based models for malaria, showing significant skill for observed malaria incidence. However, the relationship between seasonal average climate and malaria risk remains unquantified. Here we explore this relationship, using a dynamic weather-driven malaria model. We also quantify key uncertainty in the malaria model, by introducing variability in one of the first order uncertainties in model formulation. Results are visualized as location-specific impact surfaces: easily integrated with ensemble seasonal climate forecasts, and intuitively communicating quantified uncertainty. Methods are demonstrated for two epidemic regions, and are not limited to malaria modeling; the visualization method could be applied to any climate impact.

  2. The 1430s: a cold period of extraordinary internal climate variability during the early Spörer Minimum with social and economic impacts in north-western and central Europe

    Science.gov (United States)

    Camenisch, Chantal; Keller, Kathrin M.; Salvisberg, Melanie; Amann, Benjamin; Bauch, Martin; Blumer, Sandro; Brázdil, Rudolf; Brönnimann, Stefan; Büntgen, Ulf; Campbell, Bruce M. S.; Fernández-Donado, Laura; Fleitmann, Dominik; Glaser, Rüdiger; González-Rouco, Fidel; Grosjean, Martin; Hoffmann, Richard C.; Huhtamaa, Heli; Joos, Fortunat; Kiss, Andrea; Kotyza, Oldřich; Lehner, Flavio; Luterbacher, Jürg; Maughan, Nicolas; Neukom, Raphael; Novy, Theresa; Pribyl, Kathleen; Raible, Christoph C.; Riemann, Dirk; Schuh, Maximilian; Slavin, Philip; Werner, Johannes P.; Wetter, Oliver

    2016-12-01

    Changes in climate affected human societies throughout the last millennium. While European cold periods in the 17th and 18th century have been assessed in detail, earlier cold periods received much less attention due to sparse information available. New evidence from proxy archives, historical documentary sources and climate model simulations permit us to provide an interdisciplinary, systematic assessment of an exceptionally cold period in the 15th century. Our assessment includes the role of internal, unforced climate variability and external forcing in shaping extreme climatic conditions and the impacts on and responses of the medieval society in north-western and central Europe.Climate reconstructions from a multitude of natural and anthropogenic archives indicate that the 1430s were the coldest decade in north-western and central Europe in the 15th century. This decade is characterised by cold winters and average to warm summers resulting in a strong seasonal cycle in temperature. Results from comprehensive climate models indicate consistently that these conditions occurred by chance due to the partly chaotic internal variability within the climate system. External forcing like volcanic eruptions tends to reduce simulated temperature seasonality and cannot explain the reconstructions. The strong seasonal cycle in temperature reduced food production and led to increasing food prices, a subsistence crisis and a famine in parts of Europe. Societies were not prepared to cope with failing markets and interrupted trade routes. In response to the crisis, authorities implemented numerous measures of supply policy and adaptation such as the installation of grain storage capacities to be prepared for future food production shortfalls.

  3. A case study in experiential learning: pharmaceutical cold chain management on wheels.

    Science.gov (United States)

    Vesper, James; Kartoglu, Ümit; Bishara, Rafik; Reeves, Thomas

    2010-01-01

    People who handle and regulate temperature-sensitive pharmaceutical products require the knowledge and skills to ensure those products maintain quality, integrity, safety, and efficacy throughout their shelf life. People best acquire such knowledge and skills through "experiential learning" that involves working with other learners and experts. The World Health Organization developed a weeklong experiential learning event for participants so they could gain experience in how temperature-sensitive products are handled, stored, and distributed throughout the length of the distribution supply chain system. This experiential learning method enabled participants to visit, critically observe, discuss and report on the various components of the cold chain process. An emphasis was placed on team members working together to learn from one another and on several global expert mentors who were available to guide the learning, share their experiences, and respond to questions. The learning event, Pharmaceutical Cold Chain Management on Wheels, has been conducted once each year since 2008 in Turkey with participants from the global pharmaceutical industry, health care providers, national regulatory authorities, and suppliers/vendors. Observations made during the course showed that it was consistent with the principles of experiential and social learning theories. Questionnaires and focus groups provided evidence of the value of the learning event and ways to improve it. Reflecting the critical elements derived from experiential and social learning theories, five factors contributed to the success of this unique experiential learning event. These factors may also have relevance in other experiential learning courses and, potentially, for experiential e-learning events.

  4. Reforecasting the ENSO Events in the Past Fifty-Seven Years (1958-2014)

    Science.gov (United States)

    Huang, B.; Shin, C. S.; Shukla, J.; Marx, L.; Balmaseda, M.; Halder, S.; Dirmeyer, P.; Kinter, J. L.

    2016-12-01

    A set of ensemble seasonal reforecasts for 1958-2014 is conducted using the National Centers for Environmental Prediction (NCEP) Climate Forecast System, version 2 (CFSv2), initialized with observation-based ocean, atmosphere, land and sea ice reanalyses, including the Eu­ropean Centre for Medium-Range Weather Forecasts (ECMWF) global ocean reanalysis version 4, the ERA-40 atmospheric reanalysis, the NCEP CFS Reanalysis for atmosphere, land and sea ice, and the NASA Global Land Data Assimilation System reanalysis version 2.0 for land. The purpose is to examine a long and continuous seasonal reforecast dataset from a modern seasonal forecast system to be used by the research community. In comparison with other current reforecasts, this dataset allows us to evaluate the degree to which El Niño and Southern Oscillation (ENSO) events can be predicted, using a larger sample of events. Furthermore, we can directly compare the predictability of the ENSO events in 1960s-70s with the more widely studied ENSO events occurring since the 1980s to examine the state-of-the-art seasonal forecast system's capability at different phases of global climate change and multidecadal variability. A major concern is whether the seasonal reforecasts before 1979 have useful skill when there were fewer ocean observations. Our preliminary examination of the reforecasts shows that, although the reforecasts have lower skill in predicting the SST anomalies in the North Pacific and North Atlantic before 1979, the prediction skill of the ENSO onset and development for 1958-1978 is comparable to that for 1979-2014. The skill of the earlier predictions declines faster in the ENSO decaying phase because the reforecasts initialized after the summer season persistently predict lingering wind and SST anomalies in the eastern equatorial Pacific during the decaying phase of several major ENSO events in the 1960s-70s. Since the 1980s, the reforecasts initialized in fall overestimate the peak SST

  5. Experimental study on an electrical deicing technology utilizing carbon fiber tape.

    Science.gov (United States)

    2012-11-01

    In cold regions, snow and ice cause serious safety problems to transportation systems. South central Alaska, particularly Anchorage, is susceptible to a number of icing : events due to frequent freeze/thaw cycles in the winter season. Traditionally, ...

  6. Ground Source Heat Pump Sub-Slab Heat Exchange Loop Performance in a Cold Climate

    Energy Technology Data Exchange (ETDEWEB)

    Mittereder, Nick [IBACOS, Inc., Pittsburgh, PA (United States); Poerschke, Andrew [IBACOS, Inc., Pittsburgh, PA (United States)

    2013-11-01

    This report presents a cold-climate project that examines an alternative approach to ground source heat pump (GSHP) ground loop design. The innovative ground loop design is an attempt to reduce the installed cost of the ground loop heat exchange portion of the system by containing the entire ground loop within the excavated location beneath the basement slab. Prior to the installation and operation of the sub-slab heat exchanger, energy modeling using TRNSYS software and concurrent design efforts were performed to determine the size and orientation of the system. One key parameter in the design is the installation of the GSHP in a low-load home, which considerably reduces the needed capacity of the ground loop heat exchanger. This report analyzes data from two cooling seasons and one heating season.

  7. Hemato-biochemical responses to packing in donkeys administered ascorbic acid during the harmattan season

    OpenAIRE

    OLAIFA, Folashade; AYO, Joseph Olusegun; AMBALI, Suleiman Folorunsho; REKWOT, Peter Ibrahim

    2012-01-01

    Experiments were performed to investigate the effect of ascorbic acid (AA) in reducing hemato-biochemical changes in pack donkeys during the cold-dry (harmattan) season. Six experimental donkeys administered orally AA (200 mg/kg) and six control donkeys not administered ascorbic acid were subjected to packing. Blood samples were collected from all donkeys for hematological and biochemical analyses. In the control donkeys, packed cell volume (PCV), erythrocyte count and hemoglobin concentratio...

  8. Distinguishing Southern Africa precipitation response by strength of El Niño events

    Science.gov (United States)

    Pomposi, C.; Funk, C. C.; Shukla, S.; Magadzire, T.

    2017-12-01

    The El Niño Southern Oscillation (ENSO) is a leading mode of interannual precipitation variability and the main source of skill for seasonal climate predictions. Interannual precipitation variability linked to ENSO can have drastic impacts on agricultural systems and food resources in the semi-arid tropics, highlighting the need for increased information regarding ENSO's links to sub-seasonal to seasonal precipitation variations. The present work describes a case study on recent precipitation variability during warm ENSO events (i.e. El Niño) for the austral summer rainy season (December-February) in Southern Africa. Using a blending of observational and model data, it is found that the probability distribution of precipitation varies according to the strength of El Niño events. Strong El Niño events show a much clearer tendency for drying than moderate or weak events, which have smaller absolute magnitude anomalies and larger spatial heterogeneity in the precipitation response. A dynamical exploration of the various precipitation responses is also completed. The techniques utilized can be easily expanded to study likelihood of drought during El Niño for a variety of other regions and also provides information about El Niño strength and its influence on regional teleconnections. Finally, this presentation will describe the channels by which seasonal forecasting information is disseminated in the region and utilized by the Famine Early Warning Systems Network to help mitigate the impacts of potential food insecurity crises.

  9. Variability of breath condensate pH may contribute to the better understanding of non-allergic seasonal respiratory diseases

    Science.gov (United States)

    Kullmann, Tamás; Szipőcs, Annamária

    2017-09-01

    The seasonal variability of certain non-allergic respiratory diseases is not clearly understood. Analysis of the breath condensate, the liquid that can be collected by breathing into a cold tube, has been proposed to bring closer to the understanding of airway pathologies. It has been assumed, that (1) airway lining fluid was a stable body liquid and (2) the breath condensate samples were representative of the airway lining fluid. Research was focussed on the identification of biomarkers indicative of respiratory pathologies. Despite 30 years of extended investigations breath condensate analysis has not gained any clinical implementation so far. The pH of the condensate is the characteristic that can be determined with the highest reproducibility. The present paper shows, that contrary to the initial assumptions, breath condensate is not a representative of the airway lining fluid, and the airway lining fluid is not a stable body liquid. Condensate pH shows baseline variability and it is influenced by drinking and by the ambient temperature. The changes in condensate pH are linked to changes in airway lining fluid pH. The variability of airway lining fluid pH may explain seasonal incidence of certain non-allergic respiratory diseases such as the catching of a common cold and the increased incidence of COPD exacerbations and exercise-induced bronchoconstriction in cold periods.

  10. Cold/menthol TRPM8 receptors initiate the cold-shock response and protect germ cells from cold-shock-induced oxidation.

    Science.gov (United States)

    Borowiec, Anne-Sophie; Sion, Benoit; Chalmel, Frédéric; D Rolland, Antoine; Lemonnier, Loïc; De Clerck, Tatiana; Bokhobza, Alexandre; Derouiche, Sandra; Dewailly, Etienne; Slomianny, Christian; Mauduit, Claire; Benahmed, Mohamed; Roudbaraki, Morad; Jégou, Bernard; Prevarskaya, Natalia; Bidaux, Gabriel

    2016-09-01

    Testes of most male mammals present the particularity of being externalized from the body and are consequently slightly cooler than core body temperature (4-8°C below). Although, hypothermia of the testis is known to increase germ cells apoptosis, little is known about the underlying molecular mechanisms, including cold sensors, transduction pathways, and apoptosis triggers. In this study, using a functional knockout mouse model of the cold and menthol receptors, dubbed transient receptor potential melastatine 8 (TRPM8) channels, we found that TRPM8 initiated the cold-shock response by differentially modulating cold- and heat-shock proteins. Besides, apoptosis of germ cells increased in proportion to the cooling level in control mice but was independent of temperature in knockout mice. We also observed that the rate of germ cell death correlated positively with the reactive oxygen species level and negatively with the expression of the detoxifying enzymes. This result suggests that the TRPM8 sensor is a key determinant of germ cell fate under hypothermic stimulation.-Borowiec, A.-S., Sion, B., Chalmel, F., Rolland, A. D., Lemonnier, L., De Clerck, T., Bokhobza, A., Derouiche, S., Dewailly, E., Slomianny, C., Mauduit, C., Benahmed, M., Roudbaraki, M., Jégou, B., Prevarskaya, N., Bidaux, G. Cold/menthol TRPM8 receptors initiate the cold-shock response and protect germ cells from cold-shock-induced oxidation. © The Author(s).

  11. On the possibility of generation of cold and additional electric energy at thermal power stations

    Science.gov (United States)

    Klimenko, A. V.; Agababov, V. S.; Borisova, P. N.

    2017-06-01

    A layout of a cogeneration plant for centralized supply of the users with electricity and cold (ECCG plant) is presented. The basic components of the plant are an expander-generator unit (EGU) and a vapor-compression thermotransformer (VCTT). At the natural-gas-pressure-reducing stations, viz., gas-distribution stations and gas-control units, the plant is connected in parallel to a throttler and replaces the latter completely or partially. The plant operates using only the energy of the natural gas flow without burning the gas; therefore, it can be classified as a fuelless installation. The authors compare the thermodynamic efficiencies of a centralized cold supply system based on the proposed plant integrated into the thermal power station scheme and a decentralized cold supply system in which the cold is generated by electrically driven vapor-compression thermotransformers installed on the user's premises. To perform comparative analysis, the exergy efficiency was taken as the criterion since in one of the systems under investigation the electricity and the cold are generated, which are energies of different kinds. It is shown that the thermodynamic efficiency of the power supply using the proposed plant proves to be higher within the entire range of the parameters under consideration. The article presents the results of investigating the impact of the gas heating temperature upstream from the expander on the electric power of the plant, its total cooling capacity, and the cooling capacities of the heat exchangers installed downstream from the EGU and the evaporator of the VCTT. The results of calculations are discussed that show that the cold generated at the gas-control unit of a powerful thermal power station can be used for the centralized supply of the cold to the ventilation and conditioning systems of both the buildings of the power station and the neighboring dwelling houses, schools, and public facilities during the summer season.

  12. Seasonal and annual variability of coastal sulphur plumes in the northern Benguela upwelling system.

    Directory of Open Access Journals (Sweden)

    Thomas Ohde

    Full Text Available We investigated the seasonal and annual variability of surface sulphur plumes in the northern Benguela upwelling system off Namibia because of their significant impacts on the marine ecosystem, fishing industry, aquaculture farming and tourism due to their toxic properties. We identified the sulphur plumes in ocean colour satellite data of the medium resolution imaging spectrometer (MERIS for the 2002-2012 time period using the differences in the spectral properties of Namibian Benguela optical water types. The sulphur events have a strong seasonal cycle with pronounced main and off-seasons forced by local and remote-driven processes. The main peak season is in late austral summer and early austral autumn at the beginning of the annual upwelling cycle caused by increasing equatorwards alongshore winds. The sulphur plume activity is high between February and April during the seasonal oxygen minimum associated with the seasonal reduction of cross-shore ventilation of the bottom waters, the seasonal southernmost position of the Angola Benguela Frontal Zone, the seasonal maximum of water mass fractions of South Atlantic and Angola Gyre Central Waters as well as the seasonal arrival of the downwelling coastal trapped waves. The off-season is in austral spring and early austral summer during increased upwelling intensity and enhanced oxygen supply. The annual variability of sulphur events is characterized by very high activities in years 2004, 2005 and 2010 interrupted by periods of lower activity in years 2002 to 2003, 2006 to 2009 and 2011 to 2012. This result can be explained by the relative contributions or adding effects of local and remote-driven forces (from the equatorial area. The probability for the occurrence of sulphur plumes is enhanced in years with a lower annual mean of upwelling intensity, decreased oxygen supply associated with decreased lateral ventilation of bottom waters, more southern position of the Angola Benguela Frontal Zone

  13. Seasonal and annual variability of coastal sulphur plumes in the northern Benguela upwelling system.

    Science.gov (United States)

    Ohde, Thomas; Dadou, Isabelle

    2018-01-01

    We investigated the seasonal and annual variability of surface sulphur plumes in the northern Benguela upwelling system off Namibia because of their significant impacts on the marine ecosystem, fishing industry, aquaculture farming and tourism due to their toxic properties. We identified the sulphur plumes in ocean colour satellite data of the medium resolution imaging spectrometer (MERIS) for the 2002-2012 time period using the differences in the spectral properties of Namibian Benguela optical water types. The sulphur events have a strong seasonal cycle with pronounced main and off-seasons forced by local and remote-driven processes. The main peak season is in late austral summer and early austral autumn at the beginning of the annual upwelling cycle caused by increasing equatorwards alongshore winds. The sulphur plume activity is high between February and April during the seasonal oxygen minimum associated with the seasonal reduction of cross-shore ventilation of the bottom waters, the seasonal southernmost position of the Angola Benguela Frontal Zone, the seasonal maximum of water mass fractions of South Atlantic and Angola Gyre Central Waters as well as the seasonal arrival of the downwelling coastal trapped waves. The off-season is in austral spring and early austral summer during increased upwelling intensity and enhanced oxygen supply. The annual variability of sulphur events is characterized by very high activities in years 2004, 2005 and 2010 interrupted by periods of lower activity in years 2002 to 2003, 2006 to 2009 and 2011 to 2012. This result can be explained by the relative contributions or adding effects of local and remote-driven forces (from the equatorial area). The probability for the occurrence of sulphur plumes is enhanced in years with a lower annual mean of upwelling intensity, decreased oxygen supply associated with decreased lateral ventilation of bottom waters, more southern position of the Angola Benguela Frontal Zone, increased mass

  14. Low frequency variability of the Indian Ocean from TOPEX/POSEIDON sea surface height anomalies

    Digital Repository Service at National Institute of Oceanography (India)

    Somayajulu, Y.K.; Murty, V.S.N.; Sarma, Y.V.B.

    and off Sumatra present large variability on both seasonal and inter-annual time scales. The SSH anomalies off Sumatra show dominant influence of warm (cold) ENSO events with peak negative (positive) anomalies coinciding with El Nino (La Nina...

  15. Cold stress alters transcription in meiotic anthers of cold tolerant chickpea (Cicer arietinum L.).

    Science.gov (United States)

    Sharma, Kamal Dev; Nayyar, Harsh

    2014-10-11

    Cold stress at reproductive phase in susceptible chickpea (Cicer arietinum L.) leads to pollen sterility induced flower abortion. The tolerant genotypes, on the other hand, produce viable pollen and set seed under cold stress. Genomic information on pollen development in cold-tolerant chickpea under cold stress is currently unavailable. DDRT-PCR analysis was carried out to identify anther genes involved in cold tolerance in chickpea genotype ICC16349 (cold-tolerant). A total of 9205 EST bands were analyzed. Cold stress altered expression of 127 ESTs (90 up-regulated, 37 down-regulated) in anthers, more than two third (92) of which were novel with unknown protein identity and function. Remaining about one third (35) belonged to several functional categories such as pollen development, signal transduction, ion transport, transcription, carbohydrate metabolism, translation, energy and cell division. The categories with more number of transcripts were carbohydrate/triacylglycerol metabolism, signal transduction, pollen development and transport. All but two transcripts in these categories were up-regulated under cold stress. To identify time of regulation after stress and organ specificity, expression levels of 25 differentially regulated transcripts were also studied in anthers at six time points and in four organs (anthers, gynoecium, leaves and roots) at four time points. Limited number of genes were involved in regulating cold tolerance in chickpea anthers. Moreover, the cold tolerance was manifested by up-regulation of majority of the differentially expressed transcripts. The anthers appeared to employ dual cold tolerance mechanism based on their protection from cold by enhancing triacylglycerol and carbohydrate metabolism; and maintenance of normal pollen development by regulating pollen development genes. Functional characterization of about two third of the novel genes is needed to have precise understanding of the cold tolerance mechanisms in chickpea anthers.

  16. Reduced early growing season freezing resistance in alpine treeline plants under elevated atmospheric CO2.

    NARCIS (Netherlands)

    Martin, M.; Gavazov, K.S.; Körner, S.; Rixen, C.

    2010-01-01

    The frequency of freezing events during the early growing season and the vulnerability to freezing of plants in European high-altitude environments could increase under future atmospheric and climate change. We tested early growing season freezing sensitivity in 10 species, from four plant

  17. Seasonal Variation of Colored Dissolved Organic Matter in Barataria Bay, Louisiana, Using Combined Landsat and Field Data

    Directory of Open Access Journals (Sweden)

    Ishan Joshi

    2015-09-01

    Full Text Available Coastal bays, such as Barataria Bay, are important transition zones between the terrigenous and marine environments that are also optically complex due to elevated amounts of particulate and dissolved constituents. Monthly field data collected over a period of 15 months in 2010 and 2011 in Barataria Bay were used to develop an empirical band ratio algorithm for the Landsat-5 TM that showed a good correlation with the Colored Dissolved Organic Matter (CDOM absorption coefficient at 355 nm (ag355 (R2 = 0.74. Landsat-derived CDOM maps generally captured the major details of CDOM distribution and seasonal influences, suggesting the potential use of Landsat imagery to monitor biogeochemistry in coastal water environments. An investigation of the seasonal variation in ag355 conducted using Landsat-derived ag355 as well as field data suggested the strong influence of seasonality in the different regions of the bay with the marine end members (lower bay experiencing generally low but highly variable ag355 and the freshwater end members (upper bay experiencing high ag355 with low variability. Barataria Bay experienced a significant increase in ag355 during the freshwater release at the Davis Pond Freshwater Diversion (DPFD following the Deep Water Horizon oil spill in 2010 and following the Mississippi River (MR flood conditions in 2011, resulting in a weak linkage to salinity in comparison to the other seasons. Tree based statistical analysis showed the influence of high river flow conditions, high- and low-pressure systems that appeared to control ag355 by ~28%, 29% and 43% of the time duration over the study period at the marine end member just outside the bay. An analysis of CDOM variability in 2010 revealed the strong influence of the MR in controlling CDOM abundance in the lower bay during the high flow conditions, while strong winds associated with cold fronts significantly increase CDOM abundance in the upper bay, thus revealing the important

  18. Timing of seasonal migration in mule deer: effects of climate, plant phenology, and life-history characteristics

    Science.gov (United States)

    Monteith, Kevin L.; Bleich, Vernon C.; Stephenson, Thomas R.; Pierce, Beck M.; Conner, Mary M.; Klaver, Robert W.; Bowyer, R. Terry

    2011-01-01

    Phenological events of plants and animals are sensitive to climatic processes. Migration is a life-history event exhibited by most large herbivores living in seasonal environments, and is thought to occur in response to dynamics of forage and weather. Decisions regarding when to migrate, however, may be affected by differences in life-history characteristics of individuals. Long-term and intensive study of a population of mule deer (Odocoileus hemionus) in the Sierra Nevada, California, USA, allowed us to document patterns of migration during 11 years that encompassed a wide array of environmental conditions. We used two new techniques to properly account for interval-censored data and disentangle effects of broad-scale climate, local weather patterns, and plant phenology on seasonal patterns of migration, while incorporating effects of individual life-history characteristics. Timing of autumn migration varied substantially among individual deer, but was associated with the severity of winter weather, and in particular, snow depth and cold temperatures. Migratory responses to winter weather, however, were affected by age, nutritional condition, and summer residency of individual females. Old females and those in good nutritional condition risked encountering severe weather by delaying autumn migration, and were thus risk-prone with respect to the potential loss of foraging opportunities in deep snow compared with young females and those in poor nutritional condition. Females that summered on the west side of the crest of the Sierra Nevada delayed autumn migration relative to east-side females, which supports the influence of the local environment on timing of migration. In contrast, timing of spring migration was unrelated to individual life-history characteristics, was nearly twice as synchronous as autumn migration, differed among years, was related to the southern oscillation index, and was influenced by absolute snow depth and advancing phenology of plants

  19. Cough & Cold Medicine Abuse

    Science.gov (United States)

    ... Videos for Educators Search English Español Cough & Cold Medicine Abuse KidsHealth / For Teens / Cough & Cold Medicine Abuse ... resfriado Why Do People Use Cough and Cold Medicines to Get High? There's an ingredient in many ...

  20. The Predictability of Dry-Season Precipitation in Tropical West Africa

    Science.gov (United States)

    Knippertz, P.; Davis, J.; Fink, A. H.

    2012-04-01

    Precipitation during the boreal winter dry season in tropical West Africa is rare but occasionally connected to high-impacts for the local population. Previous work has shown that these events are usually connected to a trough over northwestern Africa, an extensive cloud plume on its eastern side, unusual precipitation at the northern and western fringes of the Sahara, and reduced surface pressure over the southern Sahara and Sahel, which allows an inflow of moist southerlies from the Gulf of Guinea to feed the unusual dry-season rainfalls. These results also suggest that the extratropical influence enhances the predictability of these events on the synoptic timescale. Here we further investigate this question for the 11 dry seasons (November-March) 1998/99-2008/09 using rainfall estimates from TRMM (Tropical Rainfall Measuring Mission) and GPCP (Global Precipitation Climatology Project), and operational ensemble predictions from the European Centre for Medium-Range Forecasts (ECMWF). All fields are averaged over the study area 7.5-15°N, 10°W-10°E that spans most of southern West Africa. For each 0000 UTC analysis time, the daily precipitation estimates are accumulated to pentads and compared with 120-hour predictions starting at the same time. Compared to TRMM, the ensemble mean shows a weak positive bias, whereas there is a substantial negative bias with regard to GPCP. Temporal correlations reach a high value of 0.8 for both datasets, showing similar synoptic variability despite the differences in total amount. Standard probabilistic evaluation methods such as relative operating characteristic (ROC) diagrams indicate remarkably good reliability, resolution and skill, particularly for lower precipitation thresholds. Not surprisingly, forecasts cluster at low probabilities for higher thresholds, but the reliability and ROC score are still reasonably high. The results show that global ensemble prediction systems are capable to predict dry-season rainfall events

  1. Operation Performance of Central Solar Heating System with Seasonal Storage Water Tank in Harbin

    Institute of Scientific and Technical Information of China (English)

    YE Ling; JIANG Yi-qiang; YAO Yang; ZHANG Shi-cong

    2009-01-01

    This paper presented a preliminary research on the central solar heating system with seasonal stor-age(CSHSSS)used in cold climate in China.A mathematical model of the solar energy seasonal storage water tank used in the central solar heating system was firstly developed based on energy conservation.This was fol-lowed by the simulation of the CSHSSS used in a two-floor villa in Harbin,and analysis of the impacts on storage water temperature of tank volume,solar collector area,tank burial depth,insulation thickness around the tank,etc.The results show there is a relatively economical tank volume to optimize the system efficiency,which de-creases with increasing tank volume at the constant collector area,and increases with increasing collector area at the constant tank volume.Furthermore,the insulation thickness has obvious effect on avoiding heat loss,while the tank burial depth doesn't.In addition-the relationship between the solar collector efficiency and storage wa-ter temperature is also obtained,it decreases quickly with increasing storing water temperature,and then in-creases slowly after starting space heating system.These may be helpful for relevant design and optimization in cold climates in China and all over the world.

  2. Seasonal shift in climatic limiting factors on tree transpiration: evidence from sap flow observations at alpine treelines in southeast Tibet

    Directory of Open Access Journals (Sweden)

    Liu Xinsheng

    2016-07-01

    Full Text Available Alpine and northern treelines are primarily controlled by low temperatures. However, little is known about the impact of low soil temperature on tree transpiration at treelines. We aim to test the hypothesis that in cold-limited forests, the main limiting factors for tree transpiration switch from low soil temperature before summer solstice to atmospheric evaporative demand after summer solstice, which generally results in low transpiration in the early growing season. Sap flow, meteorological factors and predawn needle water potential were continuously monitored throughout one growing season across Smith fir (Abies georgei var. smithii and juniper (Juniperus saltuaria treelines in southeast Tibet. Sap flow started in early May and corresponded to a threshold mean air-temperature of 0 oC. Across tree species, transpiration was mainly limited by low soil temperature prior to the summer solstice but by vapor pressure deficit and solar radiation post-summer solstice, which was further confirmed on a daily scale. As a result, tree transpiration for both tree species was significantly reduced in the pre-summer solstice period as compared to post-summer solstice, resulting in a lower predawn needle water potential for Smith fir trees in the early growing season. Our data supported the hypothesis, suggesting that tree transpiration mainly responds to soil temperature variations in the early growing season. The results are important for understanding the hydrological response of cold-limited forest ecosystems to climate change.

  3. Forecasting European cold waves based on subsampling strategies of CMIP5 and Euro-CORDEX ensembles

    Science.gov (United States)

    Cordero-Llana, Laura; Braconnot, Pascale; Vautard, Robert; Vrac, Mathieu; Jezequel, Aglae

    2016-04-01

    Forecasting future extreme events under the present changing climate represents a difficult task. Currently there are a large number of ensembles of simulations for climate projections that take in account different models and scenarios. However, there is a need for reducing the size of the ensemble to make the interpretation of these simulations more manageable for impact studies or climate risk assessment. This can be achieved by developing subsampling strategies to identify a limited number of simulations that best represent the ensemble. In this study, cold waves are chosen to test different approaches for subsampling available simulations. The definition of cold waves depends on the criteria used, but they are generally defined using a minimum temperature threshold, the duration of the cold spell as well as their geographical extend. These climate indicators are not universal, highlighting the difficulty of directly comparing different studies. As part of the of the CLIPC European project, we use daily surface temperature data obtained from CMIP5 outputs as well as Euro-CORDEX simulations to predict future cold waves events in Europe. From these simulations a clustering method is applied to minimise the number of ensembles required. Furthermore, we analyse the different uncertainties that arise from the different model characteristics and definitions of climate indicators. Finally, we will test if the same subsampling strategy can be used for different climate indicators. This will facilitate the use of the subsampling results for a wide number of impact assessment studies.

  4. Birth seasonality and offspring production in threatened neotropical primates related to climate

    Science.gov (United States)

    Wiederholt, R.; Post, E.

    2011-01-01

    Given the threatened status of many primate species, the impacts of global warming on primate reproduction and, consequently, population growth should be of concern. We examined relations between climatic variability and birth seasonality, offspring production, and infant sex ratios in two ateline primates, northern muriquis, and woolly monkeys. In both species, the annual birth season was delayed by dry conditions and El Ni??o years, and delayed birth seasons were linked to lower birth rates. Additionally, increased mean annual temperatures were associated with lower birth rates for northern muriquis. Offspring sex ratios varied with climatic conditions in both species, but in different ways: directly in woolly monkeys and indirectly in northern muriquis. Woolly monkeys displayed an increase in the proportion of males among offspring in association with El Ni??o events, whereas in northern muriquis, increases in the proportion of males among offspring were associated with delayed onset of the birth season, which itself was related, although weakly, to warm, dry conditions. These results illustrate that global warming, increased drought frequency, and changes in the frequency of El Ni??o events could limit primate reproductive output, threatening the persistence and recovery of ateline primate populations. ?? 2011 Blackwell Publishing Ltd.

  5. Impact of tornadoes on hospital admissions for acute cardiovascular events.

    Science.gov (United States)

    Silva-Palacios, Federico; Casanegra, Ana Isabel; Shapiro, Alan; Phan, Minh; Hawkins, Beau; Li, Ji; Stoner, Julie; Tafur, Alfonso

    2015-11-01

    There is a paucity of data describing cardiovascular events after tornado outbreaks. We proposed to study the effects of tornadoes on the incidence of cardiovascular events at a tertiary care institution. Hospital admission records from a single center situated in a tornado-prone area three months before and after a 2013 tornado outbreak were abstracted. To control for seasonal variation, we also abstracted data from the same period of the prior year (control). Hospital admissions for cardiovascular events (CVEs) including acute myocardial infarction, stroke and venous thromboembolism (VTE) were summated by zip codes, and compared by time period. There were 22,607 admissions analyzed, of which 6,705 (30%), 7,980 (35%), and 7,922 (35%) were during the pre-tornado, post-tornado, and control time frames, respectively. There were 344 CVE in the controls, 317 CVE in pre-tornado and 364 CVEs in post tornado periods. There was no difference in the prevalence of CVE during the post-tornado season compared with the control (PPR=1.05 95% CI: 0.91 to 1.21, p=0.50) or the pre-tornado season (PPR=0.96, 95% CI: 0.83 to 1.21, p=0.63). In conclusion, tornado outbreaks did not increase the prevalence of cardiovascular events. In contrast to the effect of hurricanes, implementation of a healthcare policy change directed toward the early treatment and prevention of cardiovascular events after tornadoes does not seem warranted. Copyright © 2015 Elsevier Ltd. All rights reserved.

  6. Seasonal change of WEPP erodibility parameters on a fallow plot

    Science.gov (United States)

    D. K. McCool; S. Dun; J. Q. Wu; W. J. Elliot

    2011-01-01

    In cold regions, frozen soil has a significant influence on runoff and water erosion. Frozen soil can reduce infiltration capacity, and the freeze-thaw processes degrade soil cohesive strength and increase soil erodibility. In the Inland Pacific Northwest of the USA, major erosion events typically occur during winter from low-intensity rain, snowmelt, or both as frozen...

  7. Synoptic climatological analysis of persistent cold air pools over the Carpathian Basin

    Science.gov (United States)

    Szabóné André, Karolina; Bartholy, Judit; Pongrácz, Rita

    2016-04-01

    A persistent cold air pool (PCAP) is a winter-time, anticyclone-related weather event over a relatively large basin. During this time the air is colder near the surface than aloft. This inversion near the surface can last even for weeks. As the cold air cools down, relative humidity increases and fog forms. The entire life cycle of a PCAP depends on the large scale circulation pattern. PCAP usually appears when an anticyclone builds up after a cold front passed over the examined basin, and it is usually destructed by a coming strong cold front of another midlatitude cyclone. Moreover, the intensity of the anticyclone affects the intensity of the PCAP. PCAP may result in different hazards for the population: (1) Temperature inversion in the surface layers together with weak wind may lead to severe air pollution causing health problems for many people, especially, elderly and children. (2) The fog and/or smog during chilly weather conditions often results in freezing rain. Both fog and freezing rain can distract transportation and electricity supply. Unfortunately, the numerical weather prediction models have difficulties to predict PCAP formation and destruction. One of the reasons is that PCAP is not defined objectively with a simple formula, which could be easily applied to the numerical output data. However, according to some recommendations from the synoptic literature, the shallow convective potential energy (SCPE) can be used to mathematically describe PCAP. In this study, we used the ERA-Interim reanalysis datasets to examine this very specific weather event (i.e., PCAP) over the Carpathian Basin. The connection between the mean sea level pressure and some PCAP measures (e.g., SCPE, energy deficit, etc.) is evaluated. For instance, we used logistic regression to identify PCAP periods over the Carpathian Basin. Then, further statistical analysis includes the evaluation of the length and intensity of these PCAP periods.

  8. Prediction of East African Seasonal Rainfall Using Simplex Canonical Correlation Analysis.

    Science.gov (United States)

    Ntale, Henry K.; Yew Gan, Thian; Mwale, Davison

    2003-06-01

    A linear statistical model, canonical correlation analysis (CCA), was driven by the Nelder-Mead simplex optimization algorithm (called CCA-NMS) to predict the standardized seasonal rainfall totals of East Africa at 3-month lead time using SLP and SST anomaly fields of the Indian and Atlantic Oceans combined together by 24 simplex optimized weights, and then `reduced' by the principal component analysis. Applying the optimized weights to the predictor fields produced better March-April-May (MAM) and September-October-November (SON) seasonal rain forecasts than a direct application of the same, unweighted predictor fields to CCA at both calibration and validation stages. Northeastern Tanzania and south-central Kenya had the best SON prediction results with both validation correlation and Hanssen-Kuipers skill scores exceeding +0.3. The MAM season was better predicted in the western parts of East Africa. The CCA correlation maps showed that low SON rainfall in East Africa is associated with cold SSTs off the Somali coast and the Benguela (Angola) coast, and low MAM rainfall is associated with a buildup of low SSTs in the Indian Ocean adjacent to East Africa and the Gulf of Guinea.

  9. The preconditioning role of Tropical Atlantic Variability in the development of the ENSO teleconnection: implications for the prediction of Nordeste rainfall

    Science.gov (United States)

    Giannini, A.; Saravanan, R.; Chang, P.

    A comparison of rainfall variability in the semi-arid Brazilian Nordeste in observations and in two sets of model simulations leads to the conclusion that the evolving interaction between Tropical Atlantic Variability (TAV) and the El Niño-Southern Oscillation (ENSO) phenomenon can explain two puzzling features of ENSO's impact on the Nordeste: (1) the event-to-event unpredictability of ENSO's impact; (2) the greater impact of cold rather than warm ENSO events during the past 50 years. The explanation is in the `preconditioning' role of Tropical Atlantic Variability. When, in seasons prior to the mature phase of ENSO, the tropical Atlantic happens to be evolving consistently with the development expected of the ENSO teleconnection, ENSO and TAV add up to force large anomalies in Nordeste rainfall. When it happens to be evolving in opposition to the canonical development of ENSO, then the net outcome is less obvious, but also less anomalous. The more frequent occurrence of tropical Atlantic conditions consistent with those that develop during a cold ENSO event, i.e. of a negative meridional sea surface temperature gradient, explains the weaker warm ENSO and stronger cold ENSO anomalies in Nordeste rainfall of the latter part of the twentieth century. Close monitoring of the evolution of the tropical Atlantic in seasons prior to the mature phase of ENSO should lead to an enhanced forecast potential.

  10. Seasonal variations in groundwater chemistry of a phreatic coastal and crystalline terrain of central Kerala, India

    Digital Repository Service at National Institute of Oceanography (India)

    Laluraj, C.M.; Gopinath, G.; DineshKumar, P.K.; Seralathan, P.

    is of higher quality than that of the coastal plain. The study further reveals the need for seasonal or multi-seasonal sampling when a geochemical characterization is performed and the recognition of physical events, such as heavy precipitation or droughts...

  11. Influenza Seasonal Summary, 2014-2015 Season

    Science.gov (United States)

    2015-08-14

    Influenza Seasonal Summarv 2014-2015 Season EpiData Center Department Communicable Disease Division NMCPHC-EDC-TR-394-2015 REPORT DOCUMENTATION... Influenza Seasonal Summary, 2014-2015 Season Sb. GRANT NUMBER $c. PROGRAM ELEMENT NUMBER 6. AUTHORjS) Sd. PROJECT NUMBER Ashleigh K McCabe, Kristen R...SUPPLEMENTARY NOTES 1<l. ABSTRACT This report summartzes influenza activity among Department of Navy (DON) and Depar1ment of Defense (DOD

  12. Commemoration of a cold war

    DEFF Research Database (Denmark)

    Farbøl, Rosanna

    2015-01-01

    This article brings together the fields of Cold War studies and memory studies. In Denmark, a remarkable institutionalisation of Cold War memory has taken place in the midst of a heated ideological battle over the past and whether to remember the Cold War as a ‘war’. Using Danish Cold War museums...... and heritage sites as case studies, this article sheds new light on the politics of history involved in Cold War commemoration. It suggests that the Cold War is commemorated as a war, yet this war memory is of a particular kind: it is a war memory without victims....

  13. Eugene Onegin the Cold War Monument: How Edmund Wilson Quarreled with Vladimir Nabokov

    Directory of Open Access Journals (Sweden)

    Tim Conley

    2014-01-01

    Full Text Available The tale of how Edmund Wilson quarreled with Vladimir Nabokov over the latter’s 1964 translation of Eugene Onegin can be instructively read as a politically charged event, specifically a “high culture” allegory of the Cold War. Dissemination of anti-Communist ideals (often in liberal and literary guises was the mandate of the Congress for Cultural Freedom, whose funding and editorial initiatives included the publication of both pre-Revolution Russian literature and, more notoriously, the journal Encounter (1953-1990, where Nabokov’s fiery “Reply” to Wilson appeared. This essay outlines the propaganda value of the Onegin debate within and to Cold War mythology.

  14. Seasonal, synoptic and diurnal variation of atmospheric water-isotopologues in the boundary layer of Southwestern Germany caused by plant transpiration, cold-front passages and dewfall.

    Science.gov (United States)

    Christner, Emanuel; Dyroff, Christoph; Kohler, Martin; Zahn, Andreas; Gonzales, Yenny; Schneider, Matthias

    2013-04-01

    Atmospheric water is an enormously crucial trace gas. It is responsible for ~70 % of the natural greenhouse effect (Schmidt et al., JGR, 2010) and carries huge amounts of latent heat. The isotopic composition of water vapor is an elegant tracer for a better understanding and quantification of the extremely complex and variable hydrological cycle in Earth's atmosphere (evaporation, cloud condensation, rainout, re-evaporation, snow), which in turn is a prerequisite to improve climate modeling and predictions. As H216O, H218O and HDO differ in vapor pressure and mass, isotope fractionation occurs due to condensation, evaporation and diffusion processes. In contrast to that, plants are able to transpire water with almost no isotope fractionation. For that reason the ratio of isotopologue concentrations in the boundary layer (BL) provides, compared to humidity measurements alone, independent and additional constraints for quantifying the strength of evaporation and transpiration. Furthermore the isotope ratios contain information about transport history of an air mass and microphysical processes, that is not accessible by humidity measurements. Within the project MUSICA (MUlti-platform remote Sensing of Isotopologues for investigating the Cycle of Atmospheric water) a commercial Picarro Analyzer L2120-i is operated at Karlsruhe in Southwestern Germany, which is continuously measuring the isotopologues H216O, HDO and H218O of atmospheric water vapor since January 2012. A one year record of H216O, HDO and H218O shows clear seasonal, synoptic and diurnal characteristics and reveals the main driving processes affecting the isotopic composition of water vapor in the Middle European BL. Changes in continental plant transpiration and evaporation throughout the year lead to a slow seasonal HDO/H216O-variation, that cannot be explained by pure Rayleigh condensation. Furthermore, cold-front passages from NW lead to fast and pronounced depletion of the HDO/H216O-ratio within

  15. Analysis of Natural Ventilation in a Passive House Located in Cold Conditions

    DEFF Research Database (Denmark)

    Oropeza-Perez, Ivan; Østergaard, Poul Alberg; Remmen, Arne

    2013-01-01

    in Vejle during cooling season, in the months of June, July and August. The dwelling belongs to a Danish project of passive houses denominated Komfort Husene, where its occupants claim there is no thermal comfort in summer time. The results show that the use of natural ventilation helps to reduce......This article shows the potential of using natural ventilation as a passive method of cooling buildings that are located in cold climate countries using Denmark as a case study. The energy saving potential of natural ventilation is found by performing thermal simulations of a household located...

  16. Cold urticaria: inhibition of cold-induced histamine release by doxantrazole.

    Science.gov (United States)

    Bentley-Phillips, C B; Eady, R A; Greaves, M W

    1978-10-01

    Thirteen patients with cold urticaria were studied to assess the effect of the systemic drug doxantrazole, which has actions resembling disodium cromoglycate, on cold evoked histamine release. The patients, all of whom developed an immediate local whealing response after cooling of the forearm, demonstrated release of histamine into venous blood draining that forearm. Following doxantrazole treatment, significant suppression of histamine release occurred. In some but not all patients this was accompanied by diminution of urtication in response to cooling. A double-blind study was carried out in 3 subjects, all of whom showed diminished cold-stimulated histamine release after doxantrazole. Two of these showed clinical improvement. Doxantrazole had no effect on erythema due to intradermal histamine, but did suppress the erythematous reaction to intradermal injection of compound 48/80. Our results suggest that doxantrazole or related anti-allergic agents might be useful in the treatment of cold urticaria.

  17. Treatment of Common Cold Patients with the Shi-Cha Capsule: A Multicenter, Double-Blind, Randomized, Placebo-Controlled, Dose-Escalation Trial

    Science.gov (United States)

    Chang, Jing; Dong, Shou-Jin; She, Bin; Zhang, Rui-Ming; Meng, Mao-Bin; Xu, Yan-Ling; Wan, Li-Ling; Shi, Ke-Hua; Pan, Jun-Hun; Mao, Bing

    2012-01-01

    This study was designed to determine the therapeutic efficacy and safety of the Shi-cha capsule, a Chinese herbal formula, in the treatment of patients with wind-cold type common cold. In our multi-center, prospective, double-blind, randomized, placebo-controlled, dose-escalation trial, patients with wind-cold type common cold received 0.6 g of Shi-cha capsule plus 0.6 g placebo (group A), 1.2 g of Shi-cha capsule (group B), or 1.2 g placebo (group C), three times daily for 3 days and followed up to 10 days. The primary end point was all symptom duration. The secondary end points were main symptom duration, minor symptom duration, the changes in cumulative symptom score, main symptom score, and minor symptom score 4 days after the treatment, as well as adverse events. A total of 377 patients were recruited and 360 met the inclusive criteria; 120 patients constituted each treatment group. Compared with patients in group C, patients in groups A and B had significant improvement in the all symptom duration, main symptom duration, minor symptom duration, as well as change from baseline of cumulative symptom score, main symptom score, and minor symptom score at day 4. The symptom durations and scores showed slight superiority of group B over group A, although these differences were not statistically significant. There were no differences in adverse events. The Shi-cha capsule is efficacious and safe for the treatment of patients with wind-cold type common cold. Larger trials are required to fully assess the benefits and safety of this treatment for common cold. PMID:23346193

  18. When Will It Be... USNO Seasons and Apsides Calculator

    Science.gov (United States)

    Chizek Frouard, Malynda; Bartlett, Jennifer Lynn

    2018-01-01

    The turning of the Earth’s seasons (solstices and equinoxes) and apsides (perihelions and aphelions) are times often used in observational astronomy and also of interest to the public. To avoid tedious calculations, the U.S. Naval Observatory (USNO) has developed an on-line interactive calculator, Earth’s Seasons and Apsides to provide information about events between 1600 and 2200. The new data service uses an Application Programming Interface (API), which returns values in JavaScript Object Notation (JSON) that can be incorporated into third-party websites or applications. For a requested year, the Earth’s Seasons and Apsides API provides the Gregorian calendar date and time of the Vernal Equinox, Summer Solstice, Autumnal Equinox, Winter Solstice, Aphelion, and Perihelion. The user may specify the time zone for their results, including the optional addition of U.S. daylight saving time for years after 1966.On-line documentation for using the API-enabled Earth’s Seasons and Apsides is available, including sample calls (http://aa.usno.navy.mil/data/docs/api.php). A traditional forms-based interface is available as well (http://aa.usno.navy.mil/data/docs/EarthSeasons.php). This data service replaces the popular Earth's Seasons: Equinoxes, Solstices, Perihelion, and Aphelion page that provided a static list of events for 2000–2025. The USNO also provides API-enabled data services for Complete Sun and Moon Data for One Day (http://aa.usno.navy.mil/data/docs/RS_OneDay.php), Dates of the Primary Phases of the Moon (http://aa.usno.navy.mil/data/docs/MoonPhase.php), Selected Christian Observances (http://aa.usno.navy.mil/data/docs/easter.php), Selected Islamic Observances (http://aa.usno.navy.mil/data/docs/islamic.php), Selected Jewish Observances (http://aa.usno.navy.mil/data/docs/passover.php), Julian Date Conversion (http://aa.usno.navy.mil/data/docs/JulianDate.php), and Sidereal Time (http://aa.usno.navy.mil/data/docs/siderealtime.php) as well as its Solar

  19. 77 FR 43117 - Meeting of the Cold War Advisory Committee for the Cold War Theme Study

    Science.gov (United States)

    2012-07-23

    ... the Cold War Advisory Committee for the Cold War Theme Study AGENCY: National Park Service, Interior... Committee Act, 5 U.S.C. Appendix, that the Cold War Advisory Committee for the Cold War Theme Study will... National Park Service (NPS) concerning the Cold War Theme Study. DATES: The teleconference meeting will be...

  20. Development of Cold Neutron Activation Station at HANARO Cold Neutron Source

    International Nuclear Information System (INIS)

    Sun, G. M.; Hoang, S. M. T.; Moon, J. H.; Chung, Y. S.; Cho, S. J.; Lee, K. H.; Park, B. G.; Choi, H. D.

    2012-01-01

    A new cold neutron source at the HANARO Research Reactor had been constructed in the framework of a five-year project, and ended in 2009. It has seven neutron guides, among which five guides were already allocated for a number of neutron scattering instruments. A new two-year project to develop a Cold Neutron Activation Station (CONAS) was carried out at the two neutron guides since May 2010, which was supported by the program of the Ministry of Education, Science and Technology, Korea. Fig. 1 shows the location of CONAS. CONAS is a complex facility including several radioanalytical instruments utilizing neutron capture reaction to analyze elements in a sample. It was designed to include three instruments like a CN-PGAA (Cold Neutron - Prompt Gamma Activation Analysis), a CN-NIPS (Cold Neutron - Neutron Induced Pair Spectrometer), and a CN-NDP (Cold Neutron - Neutron-induced prompt charged particle Depth Profiling). Fig. 2 shows the conceptual configuration of the CONAS concrete bioshield and the instruments. CN-PGAA and CN-NIPS measure the gamma-rays promptly emitted from the sample after neutron capture, whereas CN-NDP is a probe to measure the charged particles emitted from the sample surface after neutron capture. For this, we constructed two cold neutron guides called CG1 and CG2B guides from the CNS

  1. Mean and variance evolutions of the hot and cold temperatures in Europe

    Energy Technology Data Exchange (ETDEWEB)

    Parey, Sylvie [EDF/R and D, Chatou Cedex (France); Dacunha-Castelle, D. [Universite Paris 11, Laboratoire de Mathematiques, Orsay (France); Hoang, T.T.H. [Universite Paris 11, Laboratoire de Mathematiques, Orsay (France); EDF/R and D, Chatou Cedex (France)

    2010-02-15

    In this paper, we examine the trends of temperature series in Europe, for the mean as well as for the variance in hot and cold seasons. To do so, we use as long and homogenous series as possible, provided by the European Climate Assessment and Dataset project for different locations in Europe, as well as the European ENSEMBLES project gridded dataset and the ERA40 reanalysis. We provide a definition of trends that we keep as intrinsic as possible and apply non-parametric statistical methods to analyse them. Obtained results show a clear link between trends in mean and variance of the whole series of hot or cold temperatures: in general, variance increases when the absolute value of temperature increases, i.e. with increasing summer temperature and decreasing winter temperature. This link is reinforced in locations where winter and summer climate has more variability. In very cold or very warm climates, the variability is lower and the link between the trends is weaker. We performed the same analysis on outputs of six climate models proposed by European teams for the 1961-2000 period (1950-2000 for one model), available through the PCMDI portal for the IPCC fourth assessment climate model simulations. The models generally perform poorly and have difficulties in capturing the relation between the two trends, especially in summer. (orig.)

  2. Support for cold neutron utilization

    International Nuclear Information System (INIS)

    Lee, Kye Hong; Han, Young Soo; Choi, Sungmin; Choi, Yong; Kwon, Hoon; Lee, Kwang Hee

    2012-06-01

    - Support for experiments by users of cold neutron scattering instrument - Short-term training of current and potential users of cold neutron scattering instrument for their effective use of the instrument - International collaboration for advanced utilization of cold neutron scattering instruments - Selection and training of qualified instrument scientists for vigorous research endeavors and outstanding achievements in experiments with cold neutron - Research on nano/bio materials using cold neutron scattering instruments - Bulk nano structure measurement using small angle neutron scattering and development of analysis technique

  3. Seasonal variability of rocky reef fish assemblages: Detecting functional and structural changes due to fishing effects

    Science.gov (United States)

    Henriques, Sofia; Pais, Miguel Pessanha; Costa, Maria José; Cabral, Henrique Nogueira

    2013-05-01

    The present study analyzed the effects of seasonal variation on the stability of fish-based metrics and their capability to detect changes in fish assemblages, which is yet poorly understood despite the general idea that guilds are more resilient to natural variability than species abundances. Three zones subject to different levels of fishing pressure inside the Arrábida Marine Protected Area (MPA) were sampled seasonally. The results showed differences between warm (summer and autumn) and cold (winter and spring) seasons, with the autumn clearly standing out. In general, the values of the metrics density of juveniles, density of invertebrate feeders and density of omnivores increased in warm seasons, which can be attributed to differences in recruitment patterns, spawning migrations and feeding activity among seasons. The density of generalist/opportunistic individuals was sensitive to the effect of fishing, with higher values at zones with the lowest level of protection, while the density of individuals with high commercial value only responded to fishing in the autumn, due to a cumulative result of both juveniles and adults abundances during this season. Overall, this study showed that seasonal variability affects structural and functional features of the fish assemblage and that might influence the detection of changes as a result of anthropogenic pressures. The choice of a specific season, during warm sea conditions after the spawning period (July-October), seems to be more adequate to assess changes on rocky-reef fish assemblages.

  4. GCM simulations of cold dry Snowball Earth atmospheres

    Science.gov (United States)

    Voigt, A.; Held, I.; Marotzke, J.

    2009-12-01

    We use the full-physics atmospheric general circulation model ECHAM5 to investigate cold and virtually dry Snowball Earth atmospheres. These result from specifying sea ice as the surface boundary condition everywhere, corresponding to a frozen aquaplanet, while keeping total solar irradiance at its present-day value of 1365 Wm-2 and setting atmospheric carbon dioxide to 300 ppmv. Here, we present four simulations corresponding to the four possible combinations of enabled or disabled diurnal and seasonal cycles. The aim of this study is twofold. First, we focus on the zonal-mean circulation of Snowball Earth atmospheres, which, due to missing moisture, might constitute an ideal though yet unexplored testbed for theories of atmospheric dynamics. Second, we investigate tropical surface temperatures with an emphasis on the impact of the diurnal and seasonal cycles. This will indicate whether the presence of the diurnal or seasonal cycle would facilitate or anticipate the escape from Snowball Earth conditions when total solar irradiance or atmospheric CO2 levels were increased. The dynamics of the tropical circulation in Snowball Earth atmospheres differs substantially from that in the modern atmosphere. The analysis of the mean zonal momentum budget reveals that the mean flow meridional advection of absolute vorticity is primarily balanced by vertical diffusion of zonal momentum. The contribution of eddies is found to be even smaller than the contribution of mean flow vertical advection of zonal momentum, the latter being usually neglected in theories for the Hadley circulation, at least in its upper tropospheric branch. Suppressing vertical diffusion of horizontal momentum above 850 hPa leads to a stronger Hadley circulation. This behaviour cannot be understood from axisymmetric models of the atmosphere, nor idealized atmospheric general circulation models, which both predict a weakening of the Hadley circulation when the vertical viscosity is decreased globally. We

  5. Inter-Seasonal Influenza is Characterized by Extended Virus Transmission and Persistence

    Science.gov (United States)

    Patterson Ross, Zoe; Komadina, Naomi; Deng, Yi-Mo; Spirason, Natalie; Kelly, Heath A.; Sullivan, Sheena G.; Barr, Ian G.; Holmes, Edward C.

    2015-01-01

    The factors that determine the characteristic seasonality of influenza remain enigmatic. Current models predict that occurrences of influenza outside the normal surveillance season within a temperate region largely reflect the importation of viruses from the alternate hemisphere or from equatorial regions in Asia. To help reveal the drivers of seasonality we investigated the origins and evolution of influenza viruses sampled during inter-seasonal periods in Australia. To this end we conducted an expansive phylogenetic analysis of 9912, 3804, and 3941 hemagglutinnin (HA) sequences from influenza A/H1N1pdm, A/H3N2, and B, respectively, collected globally during the period 2009-2014. Of the 1475 viruses sampled from Australia, 396 (26.8% of Australian, or 2.2% of global set) were sampled outside the monitored temperate influenza surveillance season (1 May – 31 October). Notably, rather than simply reflecting short-lived importations of virus from global localities with higher influenza prevalence, we documented a variety of more complex inter-seasonal transmission patterns including “stragglers” from the preceding season and “heralds” of the forthcoming season, and which included viruses sampled from clearly temperate regions within Australia. We also provide evidence for the persistence of influenza B virus between epidemic seasons, in which transmission of a viral lineage begins in one season and continues throughout the inter-seasonal period into the following season. Strikingly, a disproportionately high number of inter-seasonal influenza transmission events occurred in tropical and subtropical regions of Australia, providing further evidence that climate plays an important role in shaping patterns of influenza seasonality. PMID:26107631

  6. Observations and simulations of snowpack cold content and its relationship to snowmelt timing and rate

    Science.gov (United States)

    Jennings, K. S.; Molotch, N. P.

    2017-12-01

    Mountain snowpacks serve as a vital water resource for more than 1 billion people across the globe. Two key properties of snowmelt—rate and timing—are controlled by the snowpack energy budget where incoming positive fluxes are balanced by a decrease in the energy deficit of the snowpack and a change in the phase of water from solid to liquid. In this context, the energy deficit, or cold content, regulates snowmelt as runoff does not commence until the deficit approaches zero. There is significant uncertainty surrounding cold content despite its relevance to snowmelt processes, likely due to the inherent difficulties in its observation. Our work has clarified the previously unresolved meteorological and energy balance controls on cold content development in seasonal snowpacks by leveraging two unique datasets from the Niwot Ridge LTER in the Rocky Mountains of Colorado. The first is a long-term snow pit record of snowpack properties from an alpine and subalpine site within the LTER. These data were augmented with a 23-year simulation of the snowpack at both sites using a quality controlled, serially complete, hourly forcing dataset. The observations and simulations both indicated that cold content primarily developed through new snowfall, while a negative energy budget provided a secondary pathway for cold content development, mainly through longwave emission and sublimation. Cold content gains from snowfall outnumbered energy balance gains by 438% in the alpine and 166% in the subalpine. Increased spring precipitation and later peak cold content significantly delayed snowmelt onset and daily melt rates were reduced by 32.2% in the alpine and 36.1% in the subalpine when an energy deficit needed to be satisfied. Furthermore, preliminary climate change simulations indicated warmer air temperatures reduced cold content accumulation, which increased the amount of snow lost to melt throughout the winter as incoming positive fluxes had to overcome smaller energy

  7. The Nav1.9 Channel Is a Key Determinant of Cold Pain Sensation and Cold Allodynia

    Directory of Open Access Journals (Sweden)

    Stéphane Lolignier

    2015-05-01

    Full Text Available Cold-triggered pain is essential to avoid prolonged exposure to harmfully low temperatures. However, the molecular basis of noxious cold sensing in mammals is still not completely understood. Here, we show that the voltage-gated Nav1.9 sodium channel is important for the perception of pain in response to noxious cold. Nav1.9 activity is upregulated in a subpopulation of damage-sensing sensory neurons responding to cooling, which allows the channel to amplify subthreshold depolarizations generated by the activation of cold transducers. Consequently, cold-triggered firing is impaired in Nav1.9−/− neurons, and Nav1.9 null mice and knockdown rats show increased cold pain thresholds. Disrupting Nav1.9 expression in rodents also alleviates cold pain hypersensitivity induced by the antineoplastic agent oxaliplatin. We conclude that Nav1.9 acts as a subthreshold amplifier in cold-sensitive nociceptive neurons and is required for the perception of cold pain under normal and pathological conditions.

  8. Calcareous nannoplankton and foraminiferal response to global Oligocene and Miocene climatic oscillations: a case study from the Western Carpathian segment of the Central Paratethys

    Directory of Open Access Journals (Sweden)

    Holcová Katarína

    2017-06-01

    Full Text Available The reactions of foraminiferal and calcareous nannoplankton assemblages to global warming and cooling events in the time intervals of ca. 27 to 19 Ma and 13.5 to 15 Ma (Oligocene and Miocene were studied in subtropical epicontinental seas influenced by local tectonic and palaeogeographic events (the Central Paratethys. Regardless of these local events, global climatic processes significantly influenced the palaeoenvironment within the marine basin. Warm intervals are characterized by a stable, humid climate and a high-nutrient regime, due primarily to increased continental input of phytodetritus and also locally due to seasonal upwelling. Coarse clastics deposited in a hyposaline environment characterize the marginal part of the basin. Aridification events causing decreased riverine input and consequent nutrient decreases, characterized cold intervals. Apparent seasonality, as well as catastrophic climatic events, induced stress conditions and the expansion of opportunistic taxa. Carbonate production and hypersaline facies characterize the marginal part of the basins. Hypersaline surface water triggered downwelling circulation and mixing of water masses. Decreased abundance or extinction of K-specialists during each cold interval accelerated their speciation in the subsequent warm interval. Local tectonic events led to discordances between local and global sea-level changes (tectonically triggered uplift or subsidence or to local salt formation (in the rain shadows of newly-created mountains.

  9. Inhibition of TRPM8 channels reduces pain in the cold pressor test in humans.

    Science.gov (United States)

    Winchester, Wendy J; Gore, Katrina; Glatt, Sophie; Petit, Wendy; Gardiner, Jennifer C; Conlon, Kelly; Postlethwaite, Michael; Saintot, Pierre-Philippe; Roberts, Sonia; Gosset, James R; Matsuura, Tomomi; Andrews, Mark D; Glossop, Paul A; Palmer, Michael J; Clear, Nicola; Collins, Susie; Beaumont, Kevin; Reynolds, David S

    2014-11-01

    The transient receptor potential (subfamily M, member 8; TRPM8) is a nonselective cation channel localized in primary sensory neurons, and is a candidate for cold thermosensing, mediation of cold pain, and bladder overactivity. Studies with TRPM8 knockout mice and selective TRPM8 channel blockers demonstrate a lack of cold sensitivity and reduced cold pain in various rodent models. Furthermore, TRPM8 blockers significantly lower body temperature. We have identified a moderately potent (IC50 = 103 nM), selective TRPM8 antagonist, PF-05105679 [(R)-3-[(1-(4-fluorophenyl)ethyl)(quinolin-3-ylcarbonyl)amino]methylbenzoic acid]. It demonstrated activity in vivo in the guinea pig bladder ice water and menthol challenge tests with an IC50 of 200 nM and reduced core body temperature in the rat (at concentrations >1219 nM). PF-05105679 was suitable for acute administration to humans and was evaluated for effects on core body temperature and experimentally induced cold pain, using the cold pressor test. Unbound plasma concentrations greater than the IC50 were achieved with 600- and 900-mg doses. The compound displayed a significant inhibition of pain in the cold pressor test, with efficacy equivalent to oxycodone (20 mg) at 1.5 hours postdose. No effect on core body temperature was observed. An unexpected adverse event (hot feeling) was reported, predominantly periorally, in 23 and 36% of volunteers (600- and 900-mg dose, respectively), which in two volunteers was nontolerable. In conclusion, this study supports a role for TRPM8 in acute cold pain signaling at doses that do not cause hypothermia. Copyright © 2014 by The American Society for Pharmacology and Experimental Therapeutics.

  10. Cold-water immersion (cryotherapy for preventing and treating muscle soreness after exercise

    Directory of Open Access Journals (Sweden)

    Chris Bleakley

    frequency of cold-water immersion varied between the different trials as did the exercises and settings. The majority of studies failed to report active surveillance of pre-defined adverse events. Fourteen studies compared cold-water immersion with passive intervention. Pooled results for muscle soreness showed statistically significant effects in favour of cold-water immersion after exercise at 24 hour (standardized mean difference, SMD -0.55, 95% CI -0.84 to -0.27; 10 trials, 48 hour (SMD -0.66, 95% CI -0.97 to -0.35; 8 trials, 72 hour (SMD -0.93; 95% CI -1.36 to -0.51; 4 trials and 96 hour (SMD -0.58; 95% CI -1.00 to -0.16; 5 trials follow-ups. These results were heterogeneous. Exploratory subgroup analyses showed that studies using cross-over designs or running-based exercises showed significantly larger effects in favour of coldwater immersion. Pooled results from two studies found cold-water immersion groups had significantly lower ratings of fatigue (MD - 1.70; 95% CI -2.49 to -0.90; 10 units scale, best to worst, and potentially improved ratings of physical recovery (MD 0.97; 95% CI -0.10 to 2.05; 10 units scale, worst to best immediately after the end of cold-water immersion. Five studies compared cold-water with contrast immersion. Pooled data for pain showed no evidence of differences between the two groups at four follow-up times (immediately, 24, 48 and 72 hours after treatment. Similar findings for pooled analyses at 24, 48 and 72 hour follow-ups applied to the four studies comparing cold-water with warm-water immersion. Single trials only compared coldwater immersion with respectively active recovery, compression and a second dose of cold water immersion at 24 hours. AUTHORS' CONCLUSIONS: There was some evidence that cold-water immersion reduces delayed onset muscle soreness after exercise compared with passive interventions involving rest or no intervention. There was insufficient evidence to conclude on other outcomes or for other comparisons. The majority

  11. Cold temperatures increase cold hardiness in the next generation Ophraella communa beetles.

    Directory of Open Access Journals (Sweden)

    Zhong-Shi Zhou

    Full Text Available The leaf beetle, Ophraella communa, has been introduced to control the spread of the common ragweed, Ambrosia artemisiifolia, in China. We hypothesized that the beetle, to be able to track host-range expansion into colder climates, can phenotypically adapt to cold temperatures across generations. Therefore, we questioned whether parental experience of colder temperatures increases cold tolerance of the progeny. Specifically, we studied the demography, including development, fecundity, and survival, as well as physiological traits, including supercooling point (SCP, water content, and glycerol content of O. communa progeny whose parents were maintained at different temperature regimes. Overall, the entire immature stage decreased survival of about 0.2%-4.2% when parents experienced cold temperatures compared to control individuals obtained from parents raised at room temperature. However, intrinsic capacity for increase (r, net reproductive rate (R 0 and finite rate of increase (λ of progeny O. communa were maximum when parents experienced cold temperatures. Glycerol contents of both female and male in progeny was significantly higher when maternal and paternal adults were cold acclimated as compared to other treatments. This resulted in the supercooling point of the progeny adults being significantly lower compared to beetles emerging from parents that experienced room temperatures. These results suggest that cold hardiness of O. communa can be promoted by cold acclimation in previous generation, and it might counter-balance reduced survival in the next generation, especially when insects are tracking their host-plants into colder climates.

  12. Exhaust Emission Characteristics of Heavy Duty Diesel Engine During Cold and Warm Start

    Directory of Open Access Journals (Sweden)

    YANG Rong

    2014-07-01

    Full Text Available Through experiment conducted on a six cylinder direct injection diesel engine with SCR catalyst, effects of coolant temperature on rail pressure, injection quantity, excess air coefficient and emissions characteristics during cold and warm start were investigated. The results showed that, the maximum injection quantity during a starting event was several times higher than idling operation mode, so was the maximal opacity in the cold and warm starting process. When coolant temperature rose up to above 20℃, NOX emissions in the starting process exhibited peculiar rise which was times higher than idling mode. Compared with engine warm start, rail pressure, cycle fuel quantity, opacity, CO and HC emissions during engine cold start were higher in the course from their transient maximal values towards stabilized idling status. NOX in the same transient course, however, were lower in cold start. As coolant temperature rose, the maximal and the idling value of rail pressure and cycle fuel injection quantity during diesel engine starting process decreased gradually, the excess air coefficient increased to a certain degree, and the maximal and idling values of NOX increased gradually.

  13. Occurrence of energetic extreme oceanic events in the Colombian Caribbean coasts and some approaches to assess their impact on ecosystems

    Science.gov (United States)

    Bernal, G.; Osorio, A. F.; Urrego, L.; Peláez, D.; Molina, E.; Zea, S.; Montoya, R. D.; Villegas, N.

    2016-12-01

    Above-normal meteorological and oceanographic conditions that generate damage on coastal ecosystems and associated human communities are called extreme oceanic events. Accurate data are needed to predict their occurrence and to understand their effects. We analyzed available data from four localities in the Colombian Caribbean to study the effect of wave-related extreme events (hurricanes, surges) in three coastal ecosystems, i.e., mangroves, beaches, and reefs. Three localities were continental (Portete Bay mangroves at the Guajira Peninsula, Bocagrande Public Beach at Cartagena City, Tayrona Natural Park reefs near Santa Marta City), and one was oceanic (Old Providence Island reefs in the San Andres and Old Providence Archipelago, SW Caribbean). We gathered data on ocean surface winds (1978-2011) for the four locations, then modeled significant wave heights, then identified extreme events, and finally tried to identify effects on the ecosystems, directly or from published literature. Wave-related extreme surges were also compiled from Colombian press news (1970-2008). Modeled wave maximums (> 5 m significant wave height) and press-reported events coincided with hurricanes, extreme dry season, mid-summer drought and northern hemisphere winter cold fronts, with neither a relationship to ENSO events, nor a temporal trend of increase, excepting Portete Bay, with a marked increase after 1995. Changes in Portete Bay mangroves were analyzed from aerial photographs before and after Tropical Storm Cesar (1996). In the 38 years before Cesar there was mangrove inland colonization, with some loss associated to beach erosion, while during the 8 years following the storm there were localized retreats and important changes in vegetation composition related to the falling of large trees and subsequent recolonization by species that are faster colonizers, and changes in soil composition brought about by inundation. Cartagena's Bocagrande Beach was followed between 2009 and 2011

  14. Geological events and Pliocene climate fluctuations explain the phylogeographical pattern of the cold water fish Rhynchocypris oxycephalus (Cypriniformes: Cyprinidae) in China.

    Science.gov (United States)

    Yu, Dan; Chen, Ming; Tang, Qiongying; Li, Xiaojuan; Liu, Huanzhang

    2014-10-25

    Rhynchocypris oxycephalus is a cold water fish with a wide geographic distribution including the relatively warm temperate regions of southern China. It also occurs in second- and third-step geomorphic areas in China. Previous studies have postulated that high-altitude populations of R. oxycephalus in southern China are Quaternary glacial relics. In this study, we used the mitochondrial gene Cytb and the nuclear gene RAG2 to investigate the species phylogeographical patterns and to test two biogeographic hypotheses: (1) that divergence between lineages supports the three-step model and (2) climatic fluctuations during the Quaternary resulted in the present distribution in southern China. Phylogenetic analysis detected three major matrilines (A, B, and C); with matrilines B and C being further subdivided into two submatrilines. Based on genetic distances and morphological differences, matriline A potentially represents a cryptic subspecies. The geographic division between matrilines B and C coincided with the division of the second and third geomorphic steps in China, suggesting a historical vicariance event. Pliocene climatic fluctuations might have facilitated the southwards dispersal of R. oxycephalus in matriline C, with the subsequent warming resulting in its split into submatrilines C1 and C2, leaving submatriline C2 as a relic in southern China. Our study demonstrates that geological events (three steps orogenesis) and climate fluctuations during the Pliocene were important factors in shaping phylogeographical patterns in R. oxycephalus. Notably, no genetic diversity was detected in several populations, all of which possessed unique genotypes. This indicates the uniqueness of local populations and calls for a special conservation plan for the whole species at the population level.

  15. Cuba and Economic Sanctions: A Cold War Strategy in the 21st Century

    National Research Council Canada - National Science Library

    Kelley, Thomas

    2004-01-01

    .... These sanctions and U.S. attitudes and perceptions were based on objectives driven by the Cold War and as such are outdated and overtaken by events. The sanctions should be lifted and diplomatic ties once again established both to support United States goals in the region and for quality of life improvements for Cuba.

  16. PHYSIOLOGICAL AND LEUKOCYTE SUBSET RESPONSES TO EXERCISE AND COLD EXPOSURE IN COLD-ACCLIMATIZED SKATERS

    Directory of Open Access Journals (Sweden)

    K. Kim

    2014-07-01

    Full Text Available We investigated physiological responses and changes in circulating immune cells following exercise in cold and thermoneutral conditions. Participants were short track skaters (n=9 who were acclimatized to cold conditions, and inline skaters (n=10 who were not acclimatized. All skaters were young, and skating at a recreational level three days per week for at least one year. Using a cross-over design, study variables were measured during 60 min of submaximal cycling (65% ·VO2max in cold (ambient temperature: 5±1°C, relative humidity: 41±9% and thermoneutral conditions (ambient temperature: 21±1°C, relative humidity: 35±5%. Heart rate, blood lactate and tympanic temperature were measured at rest, during exercise and recovery. Plasma cortisol, calprotectin and circulating blood cell numbers were measured before and after 60 min of cold or thermoneutral conditions, and during recovery from exercise. Heart rate was lower in both groups during exercise in cold versus thermoneutral conditions (P<0.05. The increase in total leukocytes during recovery was primarily due to an increase in neutrophils in both groups. The cold-acclimatized group activated neutrophils after exercise in cold exposure, whereas the non-acclimatized group activated lymphocyte and cortisol after exercise in cold exposure. Lymphocyte subsets significantly changed in both groups over time during recovery as compared to rest. Immediately after exercise in both groups, CD16+ and CD69+ cells were elevated compared to rest or before exercise in both conditions. Acclimatization to exercise in the cold does not appear to influence exercise-induced immune changes in cold conditions, with the possible exception of neutrophils, lymphocytes and cortisol concentration.

  17. Seasonal prediction skill of ECMWF System 4 and NCEP CFSv2 retrospective forecast for the Northern Hemisphere Winter

    International Nuclear Information System (INIS)

    Kim, Hye-Mi; Webster, Peter J.; Curry, Judith A.

    2012-01-01

    The seasonal prediction skill for the Northern Hemisphere winter is assessed using retrospective predictions (1982-2010) from the ECMWF System 4 (Sys4) and National Center for Environmental Prediction (NCEP) CFS version 2 (CFSv2) coupled atmosphere-ocean seasonal climate prediction systems. Sys4 shows a cold bias in the equatorial Pacific but a warm bias is found in the North Pacific and part of the North Atlantic. The CFSv2 has strong warm bias from the cold tongue region of the eastern Pacific to the equatorial central Pacific and cold bias in broad areas over the North Pacific and the North Atlantic. A cold bias in the Southern Hemisphere is common in both reforecasts. In addition, excessive precipitation is found in the equatorial Pacific, the equatorial Indian Ocean and the western Pacific in Sys4, and in the South Pacific, the southern Indian Ocean and the western Pacific in CFSv2. A dry bias is found for both modeling systems over South America and northern Australia. The mean prediction skill of 2 meter temperature (2mT) and precipitation anomalies are greater over the tropics than the extra-tropics and also greater over ocean than land. The prediction skill of tropical 2mT and precipitation is greater in strong El Nino Southern Oscillation (ENSO) winters than in weak ENSO winters. Both models predict the year-to-year ENSO variation quite accurately, although sea surface temperature trend bias in CFSv2 over the tropical Pacific results in lower prediction skill for the CFSv2 relative to the Sys4. Both models capture the main ENSO teleconnection pattern of strong anomalies over the tropics, the North Pacific and the North America. However, both models have difficulty in forecasting the year-to-year winter temperature variability over the US and northern Europe. (orig.)

  18. Seasonal prediction skill of ECMWF System 4 and NCEP CFSv2 retrospective forecast for the Northern Hemisphere Winter

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Hye-Mi; Webster, Peter J.; Curry, Judith A. [Georgia Institute of Technology, School of Earth and Atmospheric Science, Atlanta, GA (United States)

    2012-12-15

    The seasonal prediction skill for the Northern Hemisphere winter is assessed using retrospective predictions (1982-2010) from the ECMWF System 4 (Sys4) and National Center for Environmental Prediction (NCEP) CFS version 2 (CFSv2) coupled atmosphere-ocean seasonal climate prediction systems. Sys4 shows a cold bias in the equatorial Pacific but a warm bias is found in the North Pacific and part of the North Atlantic. The CFSv2 has strong warm bias from the cold tongue region of the eastern Pacific to the equatorial central Pacific and cold bias in broad areas over the North Pacific and the North Atlantic. A cold bias in the Southern Hemisphere is common in both reforecasts. In addition, excessive precipitation is found in the equatorial Pacific, the equatorial Indian Ocean and the western Pacific in Sys4, and in the South Pacific, the southern Indian Ocean and the western Pacific in CFSv2. A dry bias is found for both modeling systems over South America and northern Australia. The mean prediction skill of 2 meter temperature (2mT) and precipitation anomalies are greater over the tropics than the extra-tropics and also greater over ocean than land. The prediction skill of tropical 2mT and precipitation is greater in strong El Nino Southern Oscillation (ENSO) winters than in weak ENSO winters. Both models predict the year-to-year ENSO variation quite accurately, although sea surface temperature trend bias in CFSv2 over the tropical Pacific results in lower prediction skill for the CFSv2 relative to the Sys4. Both models capture the main ENSO teleconnection pattern of strong anomalies over the tropics, the North Pacific and the North America. However, both models have difficulty in forecasting the year-to-year winter temperature variability over the US and northern Europe. (orig.)

  19. Arctic sea ice trends, variability and implications for seasonal ice forecasting.

    Science.gov (United States)

    Serreze, Mark C; Stroeve, Julienne

    2015-07-13

    September Arctic sea ice extent over the period of satellite observations has a strong downward trend, accompanied by pronounced interannual variability with a detrended 1 year lag autocorrelation of essentially zero. We argue that through a combination of thinning and associated processes related to a warming climate (a stronger albedo feedback, a longer melt season, the lack of especially cold winters) the downward trend itself is steepening. The lack of autocorrelation manifests both the inherent large variability in summer atmospheric circulation patterns and that oceanic heat loss in winter acts as a negative (stabilizing) feedback, albeit insufficient to counter the steepening trend. These findings have implications for seasonal ice forecasting. In particular, while advances in observing sea ice thickness and assimilating thickness into coupled forecast systems have improved forecast skill, there remains an inherent limit to predictability owing to the largely chaotic nature of atmospheric variability. © 2015 The Author(s) Published by the Royal Society. All rights reserved.

  20. Land-surface initialisation improves seasonal climate prediction skill for maize yield forecast.

    Science.gov (United States)

    Ceglar, Andrej; Toreti, Andrea; Prodhomme, Chloe; Zampieri, Matteo; Turco, Marco; Doblas-Reyes, Francisco J

    2018-01-22

    Seasonal crop yield forecasting represents an important source of information to maintain market stability, minimise socio-economic impacts of crop losses and guarantee humanitarian food assistance, while it fosters the use of climate information favouring adaptation strategies. As climate variability and extremes have significant influence on agricultural production, the early prediction of severe weather events and unfavourable conditions can contribute to the mitigation of adverse effects. Seasonal climate forecasts provide additional value for agricultural applications in several regions of the world. However, they currently play a very limited role in supporting agricultural decisions in Europe, mainly due to the poor skill of relevant surface variables. Here we show how a combined stress index (CSI), considering both drought and heat stress in summer, can predict maize yield in Europe and how land-surface initialised seasonal climate forecasts can be used to predict it. The CSI explains on average nearly 53% of the inter-annual maize yield variability under observed climate conditions and shows how concurrent heat stress and drought events have influenced recent yield anomalies. Seasonal climate forecast initialised with realistic land-surface achieves better (and marginally useful) skill in predicting the CSI than with climatological land-surface initialisation in south-eastern Europe, part of central Europe, France and Italy.

  1. Cold fusion, Alchemist's dream

    International Nuclear Information System (INIS)

    Clayton, E.D.

    1989-09-01

    In this report the following topics relating to cold fusion are discussed: muon catalysed cold fusion; piezonuclear fusion; sundry explanations pertaining to cold fusion; cosmic ray muon catalysed cold fusion; vibrational mechanisms in excited states of D 2 molecules; barrier penetration probabilities within the hydrogenated metal lattice/piezonuclear fusion; branching ratios of D 2 fusion at low energies; fusion of deuterons into 4 He; secondary D+T fusion within the hydrogenated metal lattice; 3 He to 4 He ratio within the metal lattice; shock induced fusion; and anomalously high isotopic ratios of 3 He/ 4 He

  2. Case report of cold-weather-induced radiation recall dermatitis after chemoradiotherapy with cisplatin

    International Nuclear Information System (INIS)

    Kindts, Isabelle; Stellamans, Karin; Planckaert, Nikie; Goethals, Laurence; Bonny, Michiel

    2014-01-01

    The radiation recall reaction (RRR) is an inflammatory reaction that occurs in previously irradiated areas. The phenomenon is probably due to an idiosyncratic hypersensitivity reaction, in which a second agent can recall the inflammatory reaction. This case report documents a cold-weather-induced radiation recall dermatitis (RRD). We observed a severe RRD in a patient after chemoradiotherapy treatment with cisplatin for a nasopharyngeal carcinoma, precipitated by cold temperatures, which developed 9 days after completion of therapy. In the medical literature, RRD following extreme cold temperatures seems to be a peculiar event. Until further information on the interaction is available, future studies on combined chemotherapy with cisplatin should be carefully monitored and any side effects clearly documented. This case suggests that environmental conditions may play a contributing role in the development of RRD. This case also implies that neither fraction size nor total radiation dose is a determining factor in the development of the dermatologic reaction. (orig.) [de

  3. Seasonal timing of first rain storms affects rare plant population dynamics

    Science.gov (United States)

    Levine, J.M.; McEachern, A.K.; Cowan, C.

    2011-01-01

    A major challenge in forecasting the ecological consequences of climate change is understanding the relative importance of changes to mean conditions vs. changes to discrete climatic events, such as storms, frosts, or droughts. Here we show that the first major storm of the growing season strongly influences the population dynamics of three rare and endangered annual plant species in a coastal California (USA) ecosystem. In a field experiment we used moisture barriers and water addition to manipulate the timing and temperature associated with first major rains of the season. The three focal species showed two- to fivefold variation in per capita population growth rates between the different storm treatments, comparable to variation found in a prior experiment imposing eightfold differences in season-long precipitation. Variation in germination was a major demographic driver of how two of three species responded to the first rains. For one of these species, the timing of the storm was the most critical determinant of its germination, while the other showed enhanced germination with colder storm temperatures. The role of temperature was further supported by laboratory trials showing enhanced germination in cooler treatments. Our work suggests that, because of species-specific cues for demographic transitions such as germination, changes to discrete climate events may be as, if not more, important than changes to season-long variables.

  4. Composite and case study analyses of the large-scale environments associated with West Pacific Polar and subtropical vertical jet superposition events

    Science.gov (United States)

    Handlos, Zachary J.

    Though considerable research attention has been devoted to examination of the Northern Hemispheric polar and subtropical jet streams, relatively little has been directed toward understanding the circumstances that conspire to produce the relatively rare vertical superposition of these usually separate features. This dissertation investigates the structure and evolution of large-scale environments associated with jet superposition events in the northwest Pacific. An objective identification scheme, using NCEP/NCAR Reanalysis 1 data, is employed to identify all jet superpositions in the west Pacific (30-40°N, 135-175°E) for boreal winters (DJF) between 1979/80 - 2009/10. The analysis reveals that environments conducive to west Pacific jet superposition share several large-scale features usually associated with East Asian Winter Monsoon (EAWM) northerly cold surges, including the presence of an enhanced Hadley Cell-like circulation within the jet entrance region. It is further demonstrated that several EAWM indices are statistically significantly correlated with jet superposition frequency in the west Pacific. The life cycle of EAWM cold surges promotes interaction between tropical convection and internal jet dynamics. Low potential vorticity (PV), high theta e tropical boundary layer air, exhausted by anomalous convection in the west Pacific lower latitudes, is advected poleward towards the equatorward side of the jet in upper tropospheric isentropic layers resulting in anomalous anticyclonic wind shear that accelerates the jet. This, along with geostrophic cold air advection in the left jet entrance region that drives the polar tropopause downward through the jet core, promotes the development of the deep, vertical PV wall characteristic of superposed jets. West Pacific jet superpositions preferentially form within an environment favoring the aforementioned characteristics regardless of EAWM seasonal strength. Post-superposition, it is shown that the west Pacific

  5. Cold neutron production and application

    International Nuclear Information System (INIS)

    Inoue, Kazuhiko; Watanabe, Noboru.

    1976-01-01

    The first part gives general introduction to cold neutrons, namely the definition and the role as a probe in basic science and technology. The second part reviews various methods of cold neutron production. Some physical characteristics required for cold moderators are presented, and a list summarizes a number of cold moderators and their reactor physics constants. The definition of flux gain factor and the measured values for liquid light- and heavy-hydrogen are also given. The cold neutron spectra in methane and liquid hydrogen measured by LINAC time-of-flight method are presented to show the advantage of solid methane. The cold neutron sources using experimental reactors or linear accelerators are explained along with the examples of existing facilities. Two Japanese programs, the one is the use of a high flux reactor and the other is the use of a LINAC, are also presented. The third part of this report reviews the application areas of cold neutrons. (Aoki, K.)

  6. Effects of cold temperatures on the excitability of rat trigeminal ganglion neurons that are not for cold-sensing

    Science.gov (United States)

    Kanda, Hirosato; Gu, Jianguo G.

    2016-01-01

    Except a small population of primary afferent neurons for sensing cold to generate the sensations of innocuous and noxious cold, it is generally believed that cold temperatures suppress the excitability of other primary afferent neurons that are not for cold-sensing. These not-for-cold-sensing neurons include the majority of non-nociceptive and nociceptive afferent neurons. In the present study we have found that not-for-cold-sensing neurons of rat trigeminal ganglia (TG) change their excitability in several ways at cooling temperatures. In nearly 70% of not-for-cold-sensing TG neurons, the cooling temperature of 15°C increases their membrane excitability. We regard these neurons as cold-active neurons. For the remaining 30% of not-for-cold-sensing TG neurons, the cooling temperature of 15°C either has no effect (regarded as cold-ineffective neurons) or suppress (regarded as cold-suppressive neurons) their membrane excitability. For cold-active neurons, the cold temperature of 15°C increases their excitability as is evidenced by the increases in action potential (AP) firing numbers and/or reduction of AP rheobase when these neurons are depolarized electrically. The cold temperature of 15°C significantly inhibits M-currents and increases membrane input resistance of cold-active neurons. Retigabine, an M-current activator, abolishes the effect of cold temperatures on AP firing but not the effect of cold temperature on AP rheobase levels. The inhibition of M-currents and the increases of membrane input resistance are likely two mechanisms by which cooling temperatures increase the excitability of not-for-cold-sensing TG neurons. PMID:26709732

  7. Identification of quantitative trait loci (QTL) controlling cold tolerance in chickpea recombinant RIL population (CRIL2) from Cicer arietinum L. x Cicer reticulatum

    Science.gov (United States)

    Published yields for chickpea (Cicer arietinum L.) are higher when the crop is planted in the fall rather than in the spring seasons (Singh et al 1989, Singh et al 1997). Because of its lack of cold hardiness alleles to survive freezing temperatures, chickpea is planted in the spring in temperate re...

  8. The Nav1.9 channel is a key determinant of cold pain sensation and cold allodynia.

    Science.gov (United States)

    Lolignier, Stéphane; Bonnet, Caroline; Gaudioso, Christelle; Noël, Jacques; Ruel, Jérôme; Amsalem, Muriel; Ferrier, Jérémy; Rodat-Despoix, Lise; Bouvier, Valentine; Aissouni, Youssef; Prival, Laetitia; Chapuy, Eric; Padilla, Françoise; Eschalier, Alain; Delmas, Patrick; Busserolles, Jérôme

    2015-05-19

    Cold-triggered pain is essential to avoid prolonged exposure to harmfully low temperatures. However, the molecular basis of noxious cold sensing in mammals is still not completely understood. Here, we show that the voltage-gated Nav1.9 sodium channel is important for the perception of pain in response to noxious cold. Nav1.9 activity is upregulated in a subpopulation of damage-sensing sensory neurons responding to cooling, which allows the channel to amplify subthreshold depolarizations generated by the activation of cold transducers. Consequently, cold-triggered firing is impaired in Nav1.9(-/-) neurons, and Nav1.9 null mice and knockdown rats show increased cold pain thresholds. Disrupting Nav1.9 expression in rodents also alleviates cold pain hypersensitivity induced by the antineoplastic agent oxaliplatin. We conclude that Nav1.9 acts as a subthreshold amplifier in cold-sensitive nociceptive neurons and is required for the perception of cold pain under normal and pathological conditions. Copyright © 2015 The Authors. Published by Elsevier Inc. All rights reserved.

  9. Long-Term Seasonal and Interannual Patterns of Marine Mammal Strandings in Subtropical Western South Atlantic

    Science.gov (United States)

    Prado, Jonatas H. F.; Mattos, Paulo H.; Silva, Kleber G.; Secchi, Eduardo R.

    2016-01-01

    Understanding temporal patterns of marine mammal occurrence is useful for establishing conservation strategies. We used a 38 yr-long dataset spanning 1976 to 2013 to describe temporal patterns and trends in marine mammal strandings along a subtropical stretch of the east coast of South America. This region is influenced by a transitional zone between tropical and temperate waters and is considered an important fishing ground off Brazil. Generalized Additive Models were used to evaluate the temporal stranding patterns of the most frequently stranded species. Forty species were documented in 12,540 stranding events. Franciscana (n = 4,574), South American fur seal, (n = 3,419), South American sea lion (n = 2,049), bottlenose dolphins (n = 293) and subantarctic fur seal (n = 219) were the most frequently stranded marine mammals. The seasonality of strandings of franciscana and bottlenose dolphin coincided with periods of higher fishing effort and strandings of South American and subantarctic fur seals with post-reproductive dispersal. For South American sea lion the seasonality of strandings is associated with both fishing effort and post-reproductive dispersal. Some clear seasonal patterns were associated with occurrence of cold- (e.g. subantarctic fur seal) and warm-water (e.g. rough-toothed dolphin) species in winter and summer, respectively. Inter-annual increases in stranding rate were observed for franciscana and South American fur seal and these are likely related to increased fishing effort and population growth, respectively. For subantarctic fur seal the stranding rate showed a slight decline while for bottlenose dolphin it remained steady. No significant year to year variation in stranding rate was observed for South American sea lion. The slight decrease in frequency of temperate/polar marine mammals and the increased occurrence of subtropical/tropical species since the late 1990s might be associated with environmental changes linked to climate change

  10. Long-Term Seasonal and Interannual Patterns of Marine Mammal Strandings in Subtropical Western South Atlantic.

    Directory of Open Access Journals (Sweden)

    Jonatas H F Prado

    Full Text Available Understanding temporal patterns of marine mammal occurrence is useful for establishing conservation strategies. We used a 38 yr-long dataset spanning 1976 to 2013 to describe temporal patterns and trends in marine mammal strandings along a subtropical stretch of the east coast of South America. This region is influenced by a transitional zone between tropical and temperate waters and is considered an important fishing ground off Brazil. Generalized Additive Models were used to evaluate the temporal stranding patterns of the most frequently stranded species. Forty species were documented in 12,540 stranding events. Franciscana (n = 4,574, South American fur seal, (n = 3,419, South American sea lion (n = 2,049, bottlenose dolphins (n = 293 and subantarctic fur seal (n = 219 were the most frequently stranded marine mammals. The seasonality of strandings of franciscana and bottlenose dolphin coincided with periods of higher fishing effort and strandings of South American and subantarctic fur seals with post-reproductive dispersal. For South American sea lion the seasonality of strandings is associated with both fishing effort and post-reproductive dispersal. Some clear seasonal patterns were associated with occurrence of cold- (e.g. subantarctic fur seal and warm-water (e.g. rough-toothed dolphin species in winter and summer, respectively. Inter-annual increases in stranding rate were observed for franciscana and South American fur seal and these are likely related to increased fishing effort and population growth, respectively. For subantarctic fur seal the stranding rate showed a slight decline while for bottlenose dolphin it remained steady. No significant year to year variation in stranding rate was observed for South American sea lion. The slight decrease in frequency of temperate/polar marine mammals and the increased occurrence of subtropical/tropical species since the late 1990s might be associated with environmental changes linked to

  11. Statistical Analysis of Interchange Injection Events from Over a Decade of Cassini Data

    Science.gov (United States)

    Azari, A.; Jia, X.; Liemohn, M. W.; Sergis, N.; Thomsen, M. F.; Mitchell, D. G.; Rymer, A. M.; Paranicas, C.; Provan, G.; Ye, S.; Cowley, S. W. H.; Hospodarsky, G. B.; Vandegriff, J. D.; Kurth, W. S.

    2017-12-01

    The Cassini spacecraft has routinely observed interchange injection events with multiple instruments since arriving at Saturn in 2004. Interchange injection events are thought to initiate from a Rayleigh-Taylor like plasma instability sourced from Saturn's rapid rotation (period 10.8 hours) and dense plasma population outgassing primarily from Enceladus, and are the primary source of mass transport in the inner/middle magnetosphere. This dense plasma must be transported outward, and to conserve magnetic flux, inward moving flux tubes of low density, energetic (> keV) plasma from the outer reaches of the Saturnian system also occur. These inward-bound flux tubes are referred to as interchange injections. We will present a statistical evaluation of the occurrence rates of interchange injections at Saturn demonstrating seasonal dependence of interchange over the entirety of the Cassini mission's equatorial orbits between 2005 and 2016. We identify interchange events from CHarge Energy Mass Spectrometer (CHEMS) H+ data using a trained and tested automated algorithm. Our event identification compares well with manual identification and previous surveys of injections by L-shell and local time (Chen and Hill, 2008, Lai et al., 2016, Kennelly et al., 2013). We find that peak rates of interchange events occur between 7 - 9 Saturn radii, in agreement with previous surveys. We also evaluate interchange by preferred local time sector and season, splitting our events into pre-equinox, equinox, and post - equinox time periods. We determine that over all seasons, nightside occurrence dominated as compared to dayside, but the preferred dayside sector shifts from pre-noon during equinox, to post-noon during post-equinox. We will further investigate seasonal dependence by presenting occurrence organized by the phase systems derived based on Saturn kilometric radiation (SKR) and magnetic field perturbations (PPO).

  12. Cold-Weather Sports

    Science.gov (United States)

    ... Videos for Educators Search English Español Cold-Weather Sports KidsHealth / For Teens / Cold-Weather Sports What's in this article? What to Do? Classes ... weather. What better time to be outdoors? Winter sports can help you burn calories, increase your cardiovascular ...

  13. A conceptual prediction model for seasonal drought processes using atmospheric and oceanic standardized anomalies and its application to four recent severe regional drought events in China

    Science.gov (United States)

    Liu, Z.; LU, G.; He, H.; Wu, Z.; He, J.

    2017-12-01

    Reliable drought prediction is fundamental for seasonal water management. Considering that drought development is closely related to the spatio-temporal evolution of large-scale circulation patterns, we develop a conceptual prediction model of seasonal drought processes based on atmospheric/oceanic Standardized Anomalies (SA). It is essentially the synchronous stepwise regression relationship between 90-day-accumulated atmospheric/oceanic SA-based predictors and 3-month SPI updated daily (SPI3). It is forced with forecasted atmospheric and oceanic variables retrieved from seasonal climate forecast systems, and it can make seamless drought prediction for operational use after a year-to-year calibration. Simulation and prediction of four severe seasonal regional drought processes in China were forced with the NCEP/NCAR reanalysis datasets and the NCEP Climate Forecast System Version 2 (CFSv2) operationally forecasted datasets, respectively. With the help of real-time correction for operational application, model application during four recent severe regional drought events in China revealed that the model is good at development prediction but weak in severity prediction. In addition to weakness in prediction of drought peak, the prediction of drought relief is possible to be predicted as drought recession. This weak performance may be associated with precipitation-causing weather patterns during drought relief. Based on initial virtual analysis on predicted 90-day prospective SPI3 curves, it shows that the 2009/2010 drought in Southwest China and 2014 drought in North China can be predicted and simulated well even for the prospective 1-75 day. In comparison, the prospective 1-45 day may be a feasible and acceptable lead time for simulation and prediction of the 2011 droughts in Southwest China and East China, after which the simulated and predicted developments clearly change.

  14. Particle formation events measured at a semirural background site in Denmark

    DEFF Research Database (Denmark)

    Wang, Fenjuan; Zhang, Zhenyi; Massling, Andreas

    2013-01-01

    according to 3D daily plots in combination with an automatic routine. A clear seasonal variation was found in the way that events occurred more frequently during the warm season from May to September and especially in June. The mean values of the apparent 6 nm particle formation rates, the growth rate......The particle formation and growth events observed at a semirural background site in Denmark were analyzed based on particle number size distribution data collected during the period from February 2005 to December 2010. The new particle formation (NPF) events have been classified visually in detail...... and the condensation sink were about 0.36 cm−3 s−1, 2.6 nm h−1, 4.3 × 10−3 s−1, respectively. A positive relationship of oxidation capacity (OX = O3 + NO2) of the atmosphere and the appearance of NPF events was found indicating that the oxidation of the atmosphere was linked to the formation of new particles...

  15. A review of terrorism and its reduction of the gender ratio at birth after seasonal adjustment.

    Science.gov (United States)

    Grech, Victor; Zammit, Dorota

    2017-12-01

    Males are born in excess of females, a ratio expressed as M/T (males:total births). The ratio exhibits seasonal variation. Furthermore, acute stressful events may result in a transient dip in male births due to excess foetal losses, reducing M/T. This study was carried out in order to identify significant M/T dips after adjusting for seasonality. Live births by gender and month were sought for acute stressful events. After seasonal correction (where appropriate), M/T dips were sought. Live births. M/T dips. This paper studied 112,226,306 live births. The following events showed dips ≤5th percentile 3-5months after these acute episodes: the Brooklyn Bridge protests, Katrina Hurricane for all 4 states and for each individual state (Alabama, Florida, Louisiana, Mississippi), the Battle in Seattle, the London bombings, The Madrid bombings (for Madrid and for Spain), the Breivik shooting, the Oklahoma City bombing and the Sandy Hook Elementary School shooting. The Virginia Polytechnic Institute and State University shooting the Fukushima Daiichi nuclear disaster also showed dips albeit slightly later. Seasonal adjustments should be taken into consideration in order to avoid Type 1 or 2 error pitfalls. Copyright © 2017 Elsevier B.V. All rights reserved.

  16. Spatio-temporal variability and trends of precipitation and extreme rainfall events in Ethiopia in 1980-2010

    Science.gov (United States)

    Gummadi, Sridhar; Rao, K. P. C.; Seid, Jemal; Legesse, Gizachew; Kadiyala, M. D. M.; Takele, Robel; Amede, Tilahun; Whitbread, Anthony

    2017-12-01

    This article summarizes the results from an analysis conducted to investigate the spatio-temporal variability and trends in the rainfall over Ethiopia over a period of 31 years from 1980 to 2010. The data is mostly observed station data supplemented by bias-corrected AgMERRA climate data. Changes in annual and Belg (March-May) and Kiremt (June to September) season rainfalls and rainy days have been analysed over the entire Ethiopia. Rainfall is characterized by high temporal variability with coefficient of variation (CV, %) varying from 9 to 30% in the annual, 9 to 69% during the Kiremt season and 15-55% during the Belg season rainfall amounts. Rainfall variability increased disproportionately as the amount of rainfall declined from 700 to 100 mm or less. No significant trend was observed in the annual rainfall amounts over the country, but increasing and decreasing trends were observed in the seasonal rainfall amounts in some areas. A declining trend is also observed in the number of rainy days especially in Oromia, Benishangul-Gumuz and Gambella regions. Trends in seasonal rainfall indicated a general decline in the Belg season and an increase in the Kiremt season rainfall amounts. The increase in rainfall during the main Kiremt season along with the decrease in the number of rainy days leads to an increase in extreme rainfall events over Ethiopia. The trends in the 95th-percentile rainfall events illustrate that the annual extreme rainfall events are increasing over the eastern and south-western parts of Ethiopia covering Oromia and Benishangul-Gumuz regions. During the Belg season, extreme rainfall events are mostly observed over central Ethiopia extending towards the southern part of the country while during the Kiremt season, they are observed over parts of Oromia, (covering Borena, Guji, Bali, west Harerge and east Harerge), Somali, Gambella, southern Tigray and Afar regions. Changes in the intensity of extreme rainfall events are mostly observed over south

  17. Seasonal dynamics of early life stages of invasive and native ctenophores give clues to invasion and bloom potential in the Baltic Sea

    DEFF Research Database (Denmark)

    Jaspers, Cornelia; Haraldsson, Matilda; Lombard, Fabien

    2013-01-01

    and distribution of larvae and eggs of these two species. We show that their occurrence is significantly but inversely related to salinity. Mertensia ovum was present year round throughout the brackish Baltic Sea but also occurred in high-saline areas during cold seasons. Larvae of M. leidyi occurred throughout......Recently, both the invasive ctenophore Mnemiopsis leidyi and the arctic Mertensia ovum were discovered in the Baltic Sea but their range expansion remains unclear due to misidentification of their larval stages. Supported by molecular species verification we describe seasonal abundance...

  18. Cold weather effects on Dresden Unit 1

    Energy Technology Data Exchange (ETDEWEB)

    Anagnostopoulos, H. [Commonwealth Edison Co., Morris, IL (United States)

    1995-03-01

    Dresden Unit 1 is in the final stages of a decommissioning effort directed at preparing the unit to enter a SAFSTOR status. Following an extended sub-zero cold wave, about 55,000 gallons of water were discovered in the lowest elevation of the spherical reactor enclosure. Cold weather had caused the freezing and breaking of several service water lines that had not been completely isolated. Two days later, at a regularly scheduled decommissioning meeting, the event was communicated to the decommissioning team, who quickly recognized the potential for freezing of a 42 inches diameter Fuel Transfer Tube that connects the sphere to the Spent Fuel Pool. The team directed that the pool gates between the adjacent Spent Fuel Pool and the Fuel Transfer Pool be installed, and a portable source of heat was installed on the Fuel Transfer Tube. It was later determined that, with the fuel pool gates removed, and with a worst case freeze break at the 502 elevation on the Fuel Transfer Tube (in the Sphere), the fuel in the Spent Fuel Pool could be uncovered to a level 3 below the top of active fuel.

  19. Tolerance to multiple climate stressors: A case study of Douglas-fir drought and cold hardiness

    Science.gov (United States)

    Bansal, Sheel; Harrington, Constance A; St. Clair, John Bradley

    2016-01-01

    Summary: 1. Drought and freeze events are two of the most common forms of climate extremes which result in tree damage or death, and the frequency and intensity of both stressors may increase with climate change. Few studies have examined natural covariation in stress tolerance traits to cope with multiple stressors among wild plant populations. 2. We assessed the capacity of coastal Douglas-fir (Pseudotsuga menziesii var. menziesii), an ecologically and economically important species in the northwestern USA, to tolerate both drought and cold stress on 35 populations grown in common gardens. We used principal components analysis to combine drought and cold hardiness trait data into generalized stress hardiness traits to model geographic variation in hardiness as a function of climate across the Douglas-fir range. 3. Drought and cold hardiness converged among populations along winter temperature gradients and diverged along summer precipitation gradients. Populations originating in regions with cold winters had relatively high tolerance to both drought and cold stress, which is likely due to overlapping adaptations for coping with winter desiccation. Populations from regions with dry summers had increased drought hardiness but reduced cold hardiness, suggesting a trade-off in tolerance mechanisms. 4. Our findings highlight the necessity to look beyond bivariate trait–climate relationships and instead consider multiple traits and climate variables to effectively model and manage for the impacts of climate change on widespread species.

  20. Cold fusion

    International Nuclear Information System (INIS)

    Koster, J.

    1989-01-01

    In this contribution the author the phenomenom of so-called cold fusion, inspired by the memorable lecture of Moshe Gai on his own search for this effect. Thus much of what follows was presented by Dr. Gai; the rest is from independent reading. What is referred to as cold fusion is of course the observation of possible products of deuteron-deuteron (d-d) fusion within deuterium-loaded (dentended) electrodes. The debate over the two vanguard cold fusion experiments has raged under far more public attention than usually accorded new scientific phenomena. The clamor commenced with the press conference of M. Fleishmann and S. Pons on March 23, 1989 and the nearly simultaneous wide circulation of a preprint of S. Jones and collaborators. The majority of work attempting to confirm these observations has at the time of this writing yet to appear in published form, but contributions to conferences and electronic mail over computer networks were certainly filled with preliminary results. To keep what follows to a reasonable length the author limit this discussion to the searches for neutron (suggested by ref. 2) or for excessive heat production (suggested by ref. 1), following a synopsis of the hypotheses of cold fusion

  1. Physiological and Molecular Response of Ostrich to the Seasonal and Diurnal Variations in Egyptian conditions

    International Nuclear Information System (INIS)

    Khalil, M.H.; Khalifa, H.H; Elaroussi, M.A.; Elsayed, M.A.; Basuony, H.A.

    2013-01-01

    Twelve immature ostrich›s birds, 7 months old were used to evaluate the effect of ambient temperature variation and diurnal effect on response changes of some physiological and chemical parameters. All birds were reared out doors and exposed to daily ambient temperatures fluctuations during summer and winter. Blood samples were taken twice, one in the morning at 7 Am and once in the afternoon at 3 Pm during a representative 7 hot days of June (summer) (40±2ºC) and the 7 cold days of January (winter) (18±2ºC). Serum calcium, inorganic phosphorus, sodium, potassium, uric acid concentrations and aldosterone level were determined. The amount of total body water (TBW) and serum heat shock proteins (HSP) were estimated. Serum calcium, phosphorus, sodium and potassium concentrations in ostrich were significantly decreased, while uric acid concentration and aldosterone hormone level were significantly increased in summer as compared in winter during both at morning and at afternoon periods. Concerning the diurnal variation, serum calcium, phosphorus, sodium and potassium concentrations and aldosterone hormone level in ostrich were significantly increased, while uric acid concentration was significantly decreased at morning as compared at afternoon during both summer and winter seasons. TBW was significantly higher in summer season by 15.04% than winter season. It is concluded from the present study that heat or cold stress has a negative effect on most of the parameters studied and we recommend must be supplement diet with some nutrients like vitamins C, and E, sodium bicarbonate or yeast to overcome the negative effect and to better perform under such conditions

  2. Effects of various intake valve timings and spark timings on combustion, cyclic THC and NOX emissions during cold start phase with idle operation in CVVT engine

    International Nuclear Information System (INIS)

    Choi, Kwan Hee; Lee, Hyung Min; Hwang, In Goo; Myung, Cha Lee; Park, Sim Soo

    2008-01-01

    In a gasoline SI engine, valve events and spark timings put forth a major influence on overall efficiency, fuel economy, and exhaust emissions. Residual gases controlled by the valve overlap can be used to reduce NOx emissions and the spark retardation technique can be used to improve raw THC emissions and catalyst light-off performance during the cold start phase. This paper investigated the behaviors of the engine and its combustion characteristics with various intake valve timings and spark timings during the fast idle condition and cold start. And cyclic THC and NOx emissions were measured at the exhaust port and their formation mechanisms were examined with fast response gas analyzers. As a result, THCs and NOx were reduced by 35% and 23% with optimizing valve overlap and spark advance during the cold transient start phase. Consequently, the valve events and ignition timings were found to significantly affect combustion phenomena and cold-start emissions

  3. Cold acclimation and cognitive performance: A review.

    Science.gov (United States)

    Jones, Douglas M; Bailey, Stephen P; Roelands, Bart; Buono, Michael J; Meeusen, Romain

    2017-12-01

    Athletes, occupational workers, and military personnel experience cold temperatures through cold air exposure or cold water immersion, both of which impair cognitive performance. Prior work has shown that neurophysiological pathways may be sensitive to the effects of temperature acclimation and, therefore, cold acclimation may be a potential strategy to attenuate cold-induced cognitive impairments for populations that are frequently exposed to cold environments. This review provides an overview of studies that examine repeated cold stress, cold acclimation, and measurements of cognitive performance to determine whether or not cold acclimation provides beneficial protection against cold-induced cognitive performance decrements. Studies included in this review assessed cognitive measures of reaction time, attention, logical reasoning, information processing, and memory. Repeated cold stress, with or without evidence of cold acclimation, appears to offer no added benefit of improving cognitive performance. However, research in this area is greatly lacking and, therefore, it is difficult to draw any definitive conclusions regarding the use of cold acclimation to improve cognitive performance during subsequent cold exposures. Given the current state of minimal knowledge on this topic, athletes, occupational workers, and military commands looking to specifically enhance cognitive performance in cold environments would likely not be advised to spend the time and effort required to become acclimated to cold. However, as more knowledge becomes available in this area, recommendations may change. Copyright © 2017 Elsevier B.V. All rights reserved.

  4. Seasonal Prediction of Taiwan's Streamflow Using Teleconnection Patterns

    Science.gov (United States)

    Chen, Chia-Jeng; Lee, Tsung-Yu

    2017-04-01

    with extreme events in empirical seasonal predictions are also carried out. Findings from this work will contribute to the development of an integrated water resources planning and management system.

  5. Multiple Time-Scale Monitoring to Address Dynamic Seasonality and Storm Pulses of Stream Water Quality in Mountainous Watersheds

    Directory of Open Access Journals (Sweden)

    Hyun-Ju Lee

    2015-11-01

    Full Text Available Rainfall variability and extreme events can amplify the seasonality and storm pulses of stream water chemistry in mountainous watersheds under monsoon climates. To establish a monitoring program optimized for identifying potential risks to stream water quality arising from rainfall variability and extremes, we examined water chemistry data collected on different timescales. At a small forested watershed, bi-weekly sampling lasted over two years, in comparison to three other biweekly sampling sites. In addition, high-frequency continuous measurements of pH, electrical conductivity, and turbidity were conducted in tandem with automatic water sampling at 2 h intervals during eight rainfall events. Biweekly monitoring showed that during the summer monsoon period, electrical conductivity (EC, dissolved oxygen (DO, and dissolved ion concentrations generally decreased, but total suspended solids (TSS slightly increased. A noticeable variation from the usual seasonal pattern was that DO levels substantially decreased during an extended drought. Bi-hourly storm event samplings exhibited large changes in the concentrations of TSS and particulate and dissolved organic carbon (POC; DOC during intense rainfall events. However, extreme fluctuations in sediment export during discharge peaks could be detected only by turbidity measurements at 5 min intervals. Concomitant measurements during rainfall events established empirical relationships between turbidity and TSS or POC. These results suggest that routine monitoring based on weekly to monthly sampling is valid only in addressing general seasonal patterns or long-lasting phenomena such as drought effects. We propose an “adaptive” monitoring scheme that combines routine monitoring for general seasonal patterns and high-frequency instrumental measurements of water quality components exhibiting rapid responses pulsing during intense rainfall events.

  6. Surge recovery techniques for the Tevatron cold compressors

    International Nuclear Information System (INIS)

    Martinez, A.; Klebaner, A.L.; Makara, J.N.; Theilacker, J.C.; Fermilab

    2006-01-01

    The Fermilab Tevatron cryogenic system utilizes high-speed centrifugal cold compressors, made by Ishikawajima-Harima Heavy Industries Co. Ltd. (IHI), for high-energy operations [1]. The compressor is designed to pump 60 g/s of 3.6 K saturated helium vapor at a pressure ratio of 2.8, with an off-design range of 40 to 70 g/s and operating speeds between 40 and 95 krpm. Since initial commissioning in 1993, Tevatron transient conditions such as quench recovery have led to multiple-location machine trips as a result of the cold compressors entering the surge regime. Historically, compressors operating at lower inlet pressures and higher speeds have been especially susceptible to these machine trips and it was not uncommon to have multiple compressor trips during large multiple-house quenches. In order to cope with these events and limit accelerator down time, surge recovery techniques have been implemented in an attempt to prevent the compressors from tripping once the machine entered this surge regime. This paper discusses the different methods of surge recovery that have been employed. Data from tests performed at the Cryogenic Test Facility at Fermilab as well as actual Tevatron operational data were utilized. In order to aid in the determination of the surge region, a full mapping study was undertaken to characterize the entire pressure field of the cold compressor. These techniques were then implemented and tested at several locations in the Tevatron with some success

  7. Assessment of the performance of CORDEX-SA experiments in simulating seasonal mean temperature over the Himalayan region for the present climate: Part I

    Science.gov (United States)

    Nengker, T.; Choudhary, A.; Dimri, A. P.

    2018-04-01

    The ability of an ensemble of five regional climate models (hereafter RCMs) under Coordinated Regional Climate Downscaling Experiments-South Asia (hereafter, CORDEX-SA) in simulating the key features of present day near surface mean air temperature (Tmean) climatology (1970-2005) over the Himalayan region is studied. The purpose of this paper is to understand the consistency in the performance of models across the ensemble, space and seasons. For this a number of statistical measures like trend, correlation, variance, probability distribution function etc. are applied to evaluate the performance of models against observation and simultaneously the underlying uncertainties between them for four different seasons. The most evident finding from the study is the presence of a large cold bias (-6 to -8 °C) which is systematically seen across all the models and across space and time over the Himalayan region. However, these RCMs with its fine resolution perform extremely well in capturing the spatial distribution of the temperature features as indicated by a consistently high spatial correlation (greater than 0.9) with the observation in all seasons. In spite of underestimation in simulated temperature and general intensification of cold bias with increasing elevation the models show a greater rate of warming than the observation throughout entire altitudinal stretch of study region. During winter, the simulated rate of warming gets even higher at high altitudes. Moreover, a seasonal response of model performance and its spatial variability to elevation is found.

  8. Mesoscale Convective Complexes (MCCs) over the Indonesian Maritime Continent during the ENSO events

    Science.gov (United States)

    Trismidianto; Satyawardhana, H.

    2018-05-01

    This study analyzed the mesoscale convective complexes (MCCs) over the Indonesian Maritime Continent (IMC) during the El Niño/Southern Oscillation (ENSO) events for the the15-year period from 2001 to 2015. The MCCs identified by infrared satellite imagery that obtained from the Himawari generation satellite data. This study has reported that the frequencies of the MCC occurrences at the El Niño and La Niña were higher than that of neutral conditions during DJF. Peak of MCC occurrences during DJF at La Niña and neutral condition is in February, while El Niño is in January. ENSO strongly affects the occurrence of MCC during the DJF season. The existences of the MCC were also accompanied by increased rainfall intensity at the locations of the MCC occurrences for all ENSO events. During JJA seasons, the MCC occurrences are always found during neutral conditions, El Niño and La Niña in Indian Ocean. MCC occurring during the JJA season on El Niño and neutral conditions averaged much longer than during the DJF season. In contrast, MCCs occurring in La Niña conditions during the JJA season are more rapidly extinct than during the DJF. It indicates that the influence of MCC during La Niña during the DJF season is stronger than during the JJA season.

  9. Experimental study of a solar-assisted ground-coupled heat pump system with solar seasonal thermal storage in severe cold areas

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Xiao; Zheng, Maoyu; Zhang, Wenyong; Zhang, Shu; Yang, Tao [School of Municipal and Environmental Engineering, Harbin Institute of Technology, NO 202 Haihe Road, Harbin, Hei Longjiang 150090 (China)

    2010-11-15

    This paper presents the experimental study of a solar-assisted ground-coupled heat pump system (SAGCHPS) with solar seasonal thermal storage installed in a detached house in Harbin. The solar seasonal thermal storage was conducted throughout the non-heating seasons. In summer, the soil was used as the heat sink to cool the building directly. In winter, the solar energy was used as a priority, and the building was heated by a ground-coupled heat pump (GCHP) and solar collectors alternately. The results show that the system can meet the heating-cooling energy needs of the building. In the heating mode, the heat directly supplied by solar collectors accounted for 49.7% of the total heating output, and the average coefficient of performance (COP) of the heat pump and the system were 4.29 and 6.55, respectively. In the cooling mode, the COP of the system reached 21.35, as the heat pump was not necessary to be started. After a year of operation, the heat extracted from the soil by the heat pump accounted for 75.5% of the heat stored by solar seasonal thermal storage. The excess heat raised the soil temperature to a higher level, which was favorable for increasing the COP of the heat pump. (author)

  10. Human whole body cold adaptation.

    OpenAIRE

    Daanen, Hein A.M.; Van Marken Lichtenbelt, Wouter D.

    2016-01-01

    ABSTRACT Reviews on whole body human cold adaptation generally do not distinguish between population studies and dedicated acclimation studies, leading to confusing results. Population studies show that indigenous black Africans have reduced shivering thermogenesis in the cold and poor cold induced vasodilation in fingers and toes compared to Caucasians and Inuit. About 40,000?y after humans left Africa, natives in cold terrestrial areas seems to have developed not only behavioral adaptations...

  11. Seasonality in the Austrian Economy: Common Seasonals and Forecasting

    OpenAIRE

    Kunst, Robert M.

    1992-01-01

    Abstract: Seasonal cointegration generalizes the idea of cointegration to processes with unit roots at frequencies different from 0. Here, also the dual notion of common trends, "common seasonals", is adopted for the seasonal case. Using a five-variable macroeconomic core system of the Austrian economy, it is demonstrated how common seasonals and seasonal cointegrating vectors look in practice. Statistical tests provide clear evidence on seasonal cointegration in the system. However, it is sh...

  12. Revisiting the Microlensing Event OGLE 2012-BLG-0026: A Solar Mass Star with Two Cold Giant Planets

    Science.gov (United States)

    Beaulieu, J.-P.; Bennett, D. P.; Batista, V.; Fukui, A.; Marquette, J.-B.; Brillant, S.; Cole, A. A.; Rogers, L. A.; Sumi, T.; Abe, F.

    2016-01-01

    Two cold gas giant planets orbiting a G-type main-sequence star in the galactic disk were previously discovered in the high-magnification microlensing event OGLE-2012-BLG-0026. Here, we present revised host star flux measurements and a refined model for the two-planet system using additional light curve data. We performed high angular resolution adaptive optics imaging with the Keck and Subaru telescopes at two epochs while the source star was still amplified. We detected the lens flux, H = 16.39 +/- 0.08. The lens, a disk star, is brighter than predicted from the modeling in the original study. We revisited the light curve modeling using additional photometric data from the B and C telescope in New Zealand and CTIO 1.3 m H-band light curve. We then include the Keck and Subaru adaptive optic observation constraints. The system is composed of an approximately 4-9 Gyr lens star of M(sub lens) = 1.06 +/- 0.05 solar mass at a distance of D(sub lens) = 4.0 +/- 0.3 kpc, orbited by two giant planets of 0.145 +/- 0.008 M(sub Jup) and 0.86 +/- 0.06 M(sub Jup), with projected separations of 4.0 +/- 0.5 au and 4.8 +/- 0.7 au, respectively. Because the lens is brighter than the source star by 16 +/- 8% in H, with no other blend within one arcsec, it will be possible to estimate its metallicity using subsequent IR spectroscopy with 8-10 m class telescopes. By adding a constraint on the metallicity it will be possible to refine the age of the system.

  13. REVISITING THE MICROLENSING EVENT OGLE 2012-BLG-0026: A SOLAR MASS STAR WITH TWO COLD GIANT PLANETS

    International Nuclear Information System (INIS)

    Beaulieu, J.-P.; Batista, V.; Marquette, J.-B.

    2016-01-01

    Two cold gas giant planets orbiting a G-type main-sequence star in the galactic disk were previously discovered in the high-magnification microlensing event OGLE-2012-BLG-0026. Here, we present revised host star flux measurements and a refined model for the two-planet system using additional light curve data. We performed high angular resolution adaptive optics imaging with the Keck and Subaru telescopes at two epochs while the source star was still amplified. We detected the lens flux, H = 16.39 ± 0.08. The lens, a disk star, is brighter than predicted from the modeling in the original study. We revisited the light curve modeling using additional photometric data from the B and C telescope in New Zealand and CTIO 1.3 m H -band light curve. We then include the Keck and Subaru adaptive optic observation constraints. The system is composed of a ∼4–9 Gyr lens star of M lens = 1.06 ± 0.05 M ⊙ at a distance of D lens = 4.0 ± 0.3 kpc, orbited by two giant planets of 0.145 ± 0.008 M Jup and 0.86 ± 0.06 M Jup , with projected separations of 4.0 ± 0.5 au and 4.8 ± 0.7 au, respectively. Because the lens is brighter than the source star by 16 ± 8% in H, with no other blend within one arcsec, it will be possible to estimate its metallicity using subsequent IR spectroscopy with 8–10 m class telescopes. By adding a constraint on the metallicity it will be possible to refine the age of the system.

  14. Human whole body cold adaptation.

    NARCIS (Netherlands)

    Daanen, Hein A.M.; Van Marken Lichtenbelt, Wouter D.

    2016-01-01

    Reviews on whole body human cold adaptation generally do not distinguish between population studies and dedicated acclimation studies, leading to confusing results. Population studies show that indigenous black Africans have reduced shivering thermogenesis in the cold and poor cold induced

  15. Spectroscopy with cold and ultra-cold neutrons

    Directory of Open Access Journals (Sweden)

    Abele Hartmut

    2015-01-01

    Full Text Available We present two new types of spectroscopy methods for cold and ultra-cold neutrons. The first method, which uses the R×B drift effect to disperse charged particles in a uniformly curved magnetic field, allows to study neutron β-decay. We aim for a precision on the 10−4 level. The second method that we refer to as gravity resonance spectroscopy (GRS allows to test Newton’s gravity law at short distances. At the level of precision we are able to provide constraints on any possible gravity-like interaction. In particular, limits on dark energy chameleon fields are improved by several orders of magnitude.

  16. Cold recovery during regasification of LNG part one: Cold utilization far from the regasification facility

    International Nuclear Information System (INIS)

    La Rocca, Vincenzo

    2010-01-01

    The paper deals with cold recovery during LNG regasification. The applications analyzed pertain to the use in deep freezing agro food industry and in space air conditioning facilities in commercial sector (Supermarkets and Hypermarkets) of cold recovered from the regasification process. A modular LNG regasification unit is proposed having the regasification capacity of 2 BCM/year of gas and it is based on use of a Power Cycle working with Ethane, this unit allows operation of cold energy transfer, contained in LNG to be regasified, in a range of temperatures suitable for multipurpose use of cold, reducing regasification process irreversibility. Some electric energy is produced by the Power Cycle, but the purpose of the modular unit is to deliver cold suitable for industrial and commercial use in the proper temperature range utilizing Carbon dioxide as secondary fluid to transfer cold from regasification site to far end users. The subject is divided in two papers: this paper deals with facilities delivering cold released during LNG regasification and related pipeline facilities to transfer cold at far end users while the other paper pertains to analysis of end users applications. Results of a detailed thermodynamic and economic analysis demonstrate the suitability of the proposal.

  17. The impact of temperature on mortality in a subtropical city: effects of cold, heat, and heat waves in São Paulo, Brazil

    Science.gov (United States)

    Son, Ji-Young; Gouveia, Nelson; Bravo, Mercedes A.; de Freitas, Clarice Umbelino; Bell, Michelle L.

    2016-01-01

    Understanding how weather impacts health is critical, especially under a changing climate; however, relatively few studies have investigated subtropical regions. We examined how mortality in São Paulo, Brazil, is affected by cold, heat, and heat waves over 14.5 years (1996-2010). We used over-dispersed generalized linear modeling to estimate heat- and cold-related mortality, and Bayesian hierarchical modeling to estimate overall effects and modification by heat wave characteristics (intensity, duration, and timing in season). Stratified analyses were performed by cause of death and individual characteristics (sex, age, education, marital status, and place of death). Cold effects on mortality appeared higher than heat effects in this subtropical city with moderate climatic conditions. Heat was associated with respiratory mortality and cold with cardiovascular mortality. Risk of total mortality was 6.1 % (95 % confidence interval 4.7, 7.6 %) higher at the 99th percentile of temperature than the 90th percentile (heat effect) and 8.6 % (6.2, 11.1 %) higher at the 1st compared to the 10th percentile (cold effect). Risks were higher for females and those with no education for heat effect, and males for cold effect. Older persons, widows, and non-hospital deaths had higher mortality risks for heat and cold. Mortality during heat waves was higher than on non-heat wave days for total, cardiovascular, and respiratory mortality. Our findings indicate that mortality in São Paulo is associated with both cold and heat and that some subpopulations are more vulnerable.

  18. The impact of temperature on mortality in a subtropical city: effects of cold, heat, and heat waves in São Paulo, Brazil.

    Science.gov (United States)

    Son, Ji-Young; Gouveia, Nelson; Bravo, Mercedes A; de Freitas, Clarice Umbelino; Bell, Michelle L

    2016-01-01

    Understanding how weather impacts health is critical, especially under a changing climate; however, relatively few studies have investigated subtropical regions. We examined how mortality in São Paulo, Brazil, is affected by cold, heat, and heat waves over 14.5 years (1996-2010). We used over-dispersed generalized linear modeling to estimate heat- and cold-related mortality, and Bayesian hierarchical modeling to estimate overall effects and modification by heat wave characteristics (intensity, duration, and timing in season). Stratified analyses were performed by cause of death and individual characteristics (sex, age, education, marital status, and place of death). Cold effects on mortality appeared higher than heat effects in this subtropical city with moderate climatic conditions. Heat was associated with respiratory mortality and cold with cardiovascular mortality. Risk of total mortality was 6.1% (95% confidence interval 4.7, 7.6%) higher at the 99th percentile of temperature than the 90th percentile (heat effect) and 8.6% (6.2, 11.1%) higher at the 1st compared to the 10th percentile (cold effect). Risks were higher for females and those with no education for heat effect, and males for cold effect. Older persons, widows, and non-hospital deaths had higher mortality risks for heat and cold. Mortality during heat waves was higher than on non-heat wave days for total, cardiovascular, and respiratory mortality. Our findings indicate that mortality in São Paulo is associated with both cold and heat and that some subpopulations are more vulnerable.

  19. The association of extreme temperatures and the incidence of tuberculosis in Japan

    Science.gov (United States)

    Onozuka, Daisuke; Hagihara, Akihito

    2015-08-01

    Seasonal variation in the incidence of tuberculosis (TB) has been widely assumed. However, few studies have investigated the association between extreme temperatures and the incidence of TB. We collected data on cases of TB and mean temperature in Fukuoka, Japan for 2008-2012 and used time-series analyses to assess the possible relationship of extreme temperatures with TB incident cases, adjusting for seasonal and interannual variation. Our analysis revealed that the occurrence of extreme heat temperature events resulted in a significant increase in the number of TB cases (relative risk (RR) 1.20, 95 % confidence interval (CI) 1.01-1.43). We also found that the occurrence of extreme cold temperature events resulted in a significant increase in the number of TB cases (RR 1.23, 95 % CI 1.05-1.45). Sex and age did not modify the effect of either heat or cold extremes. Our study provides quantitative evidence that the number of TB cases increased significantly with extreme heat and cold temperatures. The results may help public health officials predict extreme temperature-related TB incidence and prepare for the implementation of preventive public health interventions.

  20. Spatial Interpolation of Historical Seasonal Rainfall Indices over Peninsular Malaysia

    Science.gov (United States)

    Hassan, Zulkarnain; Haidir, Ahmad; Saad, Farah Naemah Mohd; Ayob, Afizah; Rahim, Mustaqqim Abdul; Ghazaly, Zuhayr Md.

    2018-03-01

    The inconsistency in inter-seasonal rainfall due to climate change will cause a different pattern in the rainfall characteristics and distribution. Peninsular Malaysia is not an exception for this inconsistency, in which it is resulting extreme events such as flood and water scarcity. This study evaluates the seasonal patterns in rainfall indices such as total amount of rainfall, the frequency of wet days, rainfall intensity, extreme frequency, and extreme intensity in Peninsular Malaysia. 40 years (1975-2015) data records have been interpolated using Inverse Distance Weighted method. The results show that the formation of rainfall characteristics are significance during the Northeast monsoon (NEM), as compared to Southwest monsoon (SWM). Also, there is a high rainfall intensity and frequency related to extreme over eastern coasts of Peninsula during the NEM season.

  1. Spatial Interpolation of Historical Seasonal Rainfall Indices over Peninsular Malaysia

    Directory of Open Access Journals (Sweden)

    Hassan Zulkarnain

    2018-01-01

    Full Text Available The inconsistency in inter-seasonal rainfall due to climate change will cause a different pattern in the rainfall characteristics and distribution. Peninsular Malaysia is not an exception for this inconsistency, in which it is resulting extreme events such as flood and water scarcity. This study evaluates the seasonal patterns in rainfall indices such as total amount of rainfall, the frequency of wet days, rainfall intensity, extreme frequency, and extreme intensity in Peninsular Malaysia. 40 years (1975-2015 data records have been interpolated using Inverse Distance Weighted method. The results show that the formation of rainfall characteristics are significance during the Northeast monsoon (NEM, as compared to Southwest monsoon (SWM. Also, there is a high rainfall intensity and frequency related to extreme over eastern coasts of Peninsula during the NEM season.

  2. Cold-climate slope deposits and landscape modifications of the Mid-Atlantic Coastal Plain, Eastern USA

    Science.gov (United States)

    Newell, Wayne L.; Dejong, B.D.

    2011-01-01

    The effects of Pleistocene cold-climate geomorphology are distributed across the weathered and eroded Mid-Atlantic Coastal Plain uplands from the Wisconsinan terminal moraine south to Tidewater Virginia. Cold-climate deposits and landscape modifications are superimposed on antecedent landscapes of old, weathered Neogene upland gravels and Pleistocene marine terraces that had been built during warm periods and sea-level highstands. In New Jersey, sequences of surficial deposits define a long history of repeating climate change events. To the south across the Delmarva Peninsula and southern Maryland, most antecedent topography has been obscured by Late Pleistocene surficial deposits. These are spatially variable and are collectively described as a cold-climate alloformation. The cold-climate alloformation includes time-transgressive details of climate deterioration from at least marine isotope stage (MIS) 4 through the end of MIS 2. Some deposits and landforms within the alloformation may be as young as the Younger Dryas. Southwards along the trend of the Potomac River, these deposits and their climatic affinities become diffused. In Virginia, a continuum of erosion and surficial deposits appears to be the product of ‘normal’ temperate, climate-forced processes. The cold-climate alloformation and more temperate deposits in Virginia are being partly covered by Holocene alluvium and bay mud.

  3. Using GRACE to constrain precipitation amount over cold mountainous basins

    Science.gov (United States)

    Behrangi, Ali; Gardner, Alex S.; Reager, John T.; Fisher, Joshua B.

    2017-01-01

    Despite the importance for hydrology and climate-change studies, current quantitative knowledge on the amount and distribution of precipitation in mountainous and high-elevation regions is limited due to instrumental and retrieval shortcomings. Here by focusing on two large endorheic basins in High Mountain Asia, we show that satellite gravimetry (Gravity Recovery and Climate Experiment (GRACE)) can be used to provide an independent estimate of monthly accumulated precipitation using mass balance equation. Results showed that the GRACE-based precipitation estimate has the highest agreement with most of the commonly used precipitation products in summer, but it deviates from them in cold months, when the other products are expected to have larger errors. It was found that most of the products capture about or less than 50% of the total precipitation estimated using GRACE in winter. Overall, Global Precipitation Climatology Project (GPCP) showed better agreement with GRACE estimate than other products. Yet on average GRACE showed 30% more annual precipitation than GPCP in the study basins. In basins of appropriate size with an absence of dense ground measurements, as is a typical case in cold mountainous regions, we find GRACE can be a viable alternative to constrain monthly and seasonal precipitation estimates from other remotely sensed precipitation products that show large bias.

  4. Regional Frequency Analysis of Extreme Dry Spells during Rainy Season in the Wei River Basin, China

    Directory of Open Access Journals (Sweden)

    Dunxian She

    2016-01-01

    Full Text Available Our research analyzes the regional changes of extreme dry spell, represented by the annual maximum dry spell length (noted as AMDSL during the rainy season in the Wei River Basin (WRB of China for 1960–2014 using the L-moments method. The mean AMDSL values increase from the west to the east of the WRB, suggesting a high dry risk in the east compared to the west in the WRB. To investigate the regional frequency more reasonably, the WRB is clustered into four homogenous subregions via the K-means method and some subjective adjustments. The goodness-of-fit test shows that the GEV, PE3, and GLO distribution can be accepted as the “best-fit” model for subregions 1 and 4, subregion 2, and subregion 3, respectively. The quantiles of AMDSL under various return levels figure out a similar spatial distribution with mean AMDSL. We also find that the dry risk in subregion 2 and subregion 4 might be higher than that in subregion 1. The relationship between ENSO events and extreme dry spell events in the rainy season with cross wavelet analysis method proves that ENSO events play a critical role in triggering extreme dry events during rainy season in the WRB.

  5. Isolation and characterization of new strains of methanogens from cold terrestrial habitats.

    Science.gov (United States)

    Simankova, Maria V; Kotsyurbenko, Oleg R; Lueders, Tillmann; Nozhevnikova, Alla N; Wagner, Bianca; Conrad, Ralf; Friedrich, Michael W

    2003-06-01

    Five strains of methanogenic archaea (MT, MS, MM, MSP, ZB) were isolated from permanently and periodically cold terrestrial habitats. Physiological and morphological studies, as well as phylogenetic analyses of the new isolates were performed. Based on sequences of the 16S rRNA and methyl-coenzyme M reductase a-subunit (mcrA) genes all new isolates are closely related to known mesophilic and psychrotolerant methanogens. Both, phylogenetic analyses and phenotypic properties allow to classify strains MT, MS, and MM as members of the genus Methanosarcina. Strain MT is a new ecotype of Methanosarcina mazei, whereas strains MM and MS are very similar to each other and can be assigned to the recently described psychrotolerant species Methanosarcina lacustris. The hydrogenotrophic strain MSP is a new ecotype of the genus Methanocorpusculum. The obligately methylotrophic strain ZB is closely related to Methanomethylovorans hollandica and can be classified as new ecotype of this species. All new isolates, including the strains from permanently cold environments, are not true psychrophiles according to their growth temperature characteristics. In spite of the ability of all isolates to grow at temperatures as low as 1-5 degrees C, all of them have their growth optima in the range of moderate temperatures (25-35 degrees C). Thus, they can be regarded as psychrotolerant organisms. Psychrotolerant methanogens are thought to play an important role in methane production in both, habitats under seasonal temperature variations or from permanently cold areas.

  6. THE COLD AND DARK PROCESS AT THE SAVANNAH RIVER SITE

    International Nuclear Information System (INIS)

    Gilmour, J; William Austin, W; Cathy Sizemore, C

    2007-01-01

    The deactivation and decommissioning (D and D) of a facility exposes D and D workers to numerous hazards. One of the more serious hazards is coming into contact to hazardous energy sources (e.g. electrical, pressurized steam). At the Savannah River Site (SRS) a formal process for identifying and eliminating sources of hazardous energy was developed and is called ''Cold and Dark''. Several ''near miss'' events involving cutting of energized conductors during D and D work in buildings thought to be isolated identified the need to have a formal process to identify and isolate these potentially hazardous systems. This process was developed using lessons learned from D and D activities at the Rocky Flats Environmental Technology Site (Rocky Flats) in Colorado. The Cold and Dark process defines an isolation boundary (usually a building perimeter) and then systematically identifies all of the penetrations through this boundary. All penetrations that involve hazardous energy sources are then physically air-gapped. The final product is a documented declaration of isolation performed by a team involving operations, engineering, and project management. Once the Cold and Dark declaration is made for a building work can proceed without the usual controls used in an operational facility (e.g. lockout/tagout, arc flash PPE). It is important to note that the Cold and Dark process does not remove all hazards from a facility. Work planning and controls still need to address hazards that can be present from such things as chemicals, radiological contamination, residual liquids, etc., as well as standard industrial hazards

  7. Treatment of external events in the linked event tree methodology NPP Goesgen - Daeniken example

    International Nuclear Information System (INIS)

    Kozlik, Thomas

    2014-01-01

    The NPP Goesgen-Daeniken uses a combined level 1 / level 2 PSA model for its event analyses. The model uses a linked event tree approach, using the software RISKMAN R . Each initiating event passes through a modularized event tree structure, consisting of external events pre-trees, alignment and support systems trees and front-line and containment response trees. This paper explains the structure of the linked event trees. Switches are used to bypass certain trees for specific initiating events. The screening process applied to possible external events is explained. The final scope of considered natural external events in the Goesgen PSA consists of earthquakes, seasonal events causing cooling water intake plugging or external floods. The structure of the natural external events pre-trees is explained. The treatment of external floods is explained in more detail. Floods at the Goesgen site are caused by extreme river flows into the old branch of the Aare river. A new model has been developed to analyse the probabilistic flood hazard using a bivariate distribution (water level and flood duration). Analysing the statistical data, the time trend had to be considered. The Goesgen PSA models 7 external flood initiating events, considering different water levels and durations at the flooded plant site. The building fragilities were developed in terms of resistance times. The RISKMAN R external flood pre-tree consists of top events for operator actions and failure of the building functions, which leads to the functional failure of equipment located at the lower elevation of the building. (author)

  8. Are glendonites reliable indicators of cold conditions? Evidence from the Lower Cretaceous of Spitsbergen

    Science.gov (United States)

    Vickers, Madeleine; Price, Gregory; Watkinson, Matthew; Jerrett, Rhodri

    2017-04-01

    Glendonites are pseudomorphs after the mineral ikaite, and have been found in marine sediments throughout geological time. Ikaite is a metastable, hydrated form of calcium carbonate, which is only stable under specific conditions: between -2 and +5 °C, and with high alkalinity and phosphate concentrations. Glendonites are often associated with cold climates due to the strong temperature control on ikaite growth, and the coincidence in the geological record with episodes of global cooling. Glendonites are found in the Lower Cretaceous succession in Spitsbergen. During the Early Cretaceous, Spitsbergen was at a palaeolatitude of 60°N, and was part of a shallow epicontinental sea that formed during the Mesozoic as Atlantic rifting propagated northwards. Though the Early Cretaceous was generally characterised by greenhouse climate conditions, episodic cold snaps occurred during the Valanginian (the "Weissert Event") and during Aptian-Albian. Using high resolution carbon-isotope stratigraphy, we show that the first occurrences of glendonites are in the upper Lower Hauterivian and in the very upper Upper Hauterivian, stratigraphically higher than the Valanginian cooling event. Glendonites are also found in horizons in the Upper Aptian, coincident with the Aptian-Albian cold snap. Petrological analysis of the glendonite structure reveals differences between the Hauterivian and Aptian glendonites, with evidence for multiple diagenetic phases of growth in the Hauterivian glendonites, suggesting oscillating chemical conditions. This evidence suggests that local environmental conditions may have a stronger control on glendonite formation and preservation than global climate. We present a new model for ikaite growth and slow transformation to glendonite in marine sediments, which points to a more complex suite of diagenetic transformations than previously modelled. Furthermore, we critically assess whether such pseudomorphs after marine sedimentary ikaite may be indicators

  9. Nearshore, seasonally persistent fronts in sea surface temperature on Red Sea tropical reefs

    KAUST Repository

    Blythe, J. N.

    2011-07-08

    Temperature variability was studied on tropical reefs off the coast of Saudi Arabia in the Red Sea using remote sensing from Aqua and Terra satellites. Cross-shore gradients in sea surface temperature (SST) were observed, including cold fronts (colder inshore) during winter and warm fronts (warmer inshore) during summer. Fronts persisted over synoptic and seasonal time-scales and had a periodic annual cycle over a 10-year time-series. Measurements of cross-shore SST variability were conducted at the scale of tens of kilometres, which encompassed temperature over shallow tropical reef complexes and the continental slope. Two tropical reefs that had similar reef geomorphology and offshore continental slope topography had identical cold fronts, although they were separated by 100 km along the Red Sea coast of Saudi Arabia. Satellite SST gradients across contours of topography of tropical reefs can be used as an index to flag areas potentially exposed to temperature stress. © 2011 International Council for the Exploration of the Sea.

  10. Nearshore, seasonally persistent fronts in sea surface temperature on Red Sea tropical reefs

    KAUST Repository

    Blythe, J. N.; da Silva, J. C. B.; Pineda, J.

    2011-01-01

    Temperature variability was studied on tropical reefs off the coast of Saudi Arabia in the Red Sea using remote sensing from Aqua and Terra satellites. Cross-shore gradients in sea surface temperature (SST) were observed, including cold fronts (colder inshore) during winter and warm fronts (warmer inshore) during summer. Fronts persisted over synoptic and seasonal time-scales and had a periodic annual cycle over a 10-year time-series. Measurements of cross-shore SST variability were conducted at the scale of tens of kilometres, which encompassed temperature over shallow tropical reef complexes and the continental slope. Two tropical reefs that had similar reef geomorphology and offshore continental slope topography had identical cold fronts, although they were separated by 100 km along the Red Sea coast of Saudi Arabia. Satellite SST gradients across contours of topography of tropical reefs can be used as an index to flag areas potentially exposed to temperature stress. © 2011 International Council for the Exploration of the Sea.

  11. A shorter snowfall season associated with higher air temperatures over northern Eurasia

    International Nuclear Information System (INIS)

    Ye Hengchun; Cohen, Judah

    2013-01-01

    The temperature sensitivity of the snowfall season (start, end, duration) over northern Eurasia (the former USSR) is analyzed from synoptic records of 547 stations from 1966 to 2000. The results find significant correlations between temperature and snowfall season at approximately 56% of stations (61% for the starting date and 56% for the ending date) with a mean snowfall season duration temperature sensitivity of −6.2 days °C −1 split over the start (2.8 days) and end periods (−3.4 days). Temperature sensitivity was observed to increase with stations’ mean seasonal air temperature, with the strongest relationships at locations of around 6 °C temperature. This implies that increasing air temperature in fall and spring will delay the onset and hasten the end of snowfall events, and reduces the snowfall season length by 6.2 days for each degree of increase. This study also clarifies that the increasing trend in snowfall season length during 1936/37–1994 over northern European Russia and central Siberia revealed in an earlier study is unlikely to be associated with warming in spring and fall seasons. (letter)

  12. Effects of life event stress, exercise workload, hardiness and coping ...

    African Journals Online (AJOL)

    Effects of life event stress, exercise workload, hardiness and coping style on susceptibility to the common cold. GA Struwig, M Papaikonomou, P Kruger. Abstract. No Abstract. South African Journal for Physical, Health Education, Recreation and DanceVol. 12(4) 2006: pp. 369-383. Full Text: EMAIL FULL TEXT EMAIL FULL ...

  13. Responsiveness of cold tolerant chickpea characteristics in fall and spring planting: II. yield and yield components

    Directory of Open Access Journals (Sweden)

    ahmad nezami

    2009-06-01

    Full Text Available Previous research in Mashhad collection chickpeas (MCC has shown that there are some cold tolerant genotypes for fall planting in the highlands. To obtain more detailed information about the reaction of these genotypes to fall and spring planting, the yield and yield component responses of 33 chickpea genotypes (32 cold tolerant genotypes and one susceptible genotypes to four planting dates (28 Sep., 16 Oct., 2 Nov., and 7 Mar. were evaluated in 2000-2001 growing season. The experiment was conducted at the experimental field of college of agriculture, Ferdowsi University of Mashhad as a split plot design with two replications. The planting dates were imposed as main plot and chickpea genotypes as subplot. Effects of planting date and genotype on percent of plant survival (PPS after winter, number. of pod per plant, 100 seed weight, yield and Harvest Index (HI were significant (p

  14. Diurnal thermoregulatory responses in pregnant Yankasa ewes to the dry season in a tropical Savannah.

    Science.gov (United States)

    Yaqub, Lukuman Surakat; Ayo, Joseph Olusegun; Kawu, Muhammad Umar; Rekwot, Peter Ibrahim

    2017-08-01

    The study investigated concomitant effect of gestation and high ambient temperature under a tropical environment on rectal temperature (RT), respiratory rate (RR) and heart rate (HR) responses in Yankasa ewes. Twenty Yankasa ewes, consisting of ten pregnant and ten non-pregnant ewes, were used for the study. Ewes were synchronised and bred, such that each gestation phase coincided with different periods of the dry-seasons, early-gestation (cold/harmattan), mid-gestation (peak hot-dry) and late-gestation (late hot-dry). The RT, RR and HR were recorded thrice, 2 days apart at middle of each gestation period at 06:00, 14:00 and 18:00 h, concurrently with dry- (DBT) and wet-bulb temperatures of the experimental pen. The DBT was positively correlated with RT, RR during the different gestation stages. The RT significantly (P ewes, with peak at 14:00 h. Values of RT and RR were higher (P ewes at mid- and late-gestation, respectively. Mean RT was lower (P ewes at early-gestation (cold-dry). The HR was (P ewes during the different gestation phases. In conclusion, ambient temperature and gestation concomitantly modulate diurnal thermoregulatory responses of the ewes to hot-dry season. Adequate measures should be adopted to mitigate adverse impact of prolonged high RR on the dam and the foetus during the peak of ambient temperature prevailing in the tropical Savannah environment.

  15. Age and Ethnic Differences in Cold Weather and Contagion Theories of Colds and Flu

    Science.gov (United States)

    Sigelman, Carol K.

    2012-01-01

    Age and ethnic group differences in cold weather and contagion or germ theories of infectious disease were explored in two studies. A cold weather theory was frequently invoked to explain colds and to a lesser extent flu but became less prominent with age as children gained command of a germ theory of disease. Explanations of how contact with…

  16. Cold knife cone biopsy

    Science.gov (United States)

    ... biopsy; Pap smear - cone biopsy; HPV - cone biopsy; Human papilloma virus - cone biopsy; Cervix - cone biopsy; Colposcopy - cone biopsy Images Female reproductive anatomy Cold cone biopsy Cold cone removal References Baggish ...

  17. Probability assessment for the incidence of extreme events due to the climatic change. Focus Germany; Berechnung der Wahrscheinlichkeiten fuer das Eintreten von Extremereignissen durch Klimaaenderungen. Schwerpunkt Deutschland

    Energy Technology Data Exchange (ETDEWEB)

    Jonas, Martin; Staeger, Tim; Schoenwiese, Christian-Dietrich [Frankfurt Univ. (Germany). Inst. fuer Atmosphaere und Umwelt, Arbeitsgruppe Klimaforschung

    2005-08-15

    The study on the probability of occurrence of extreme weather events in Germany is based on compiled data covering ground-level temperature, precipitation and wind during the time period 1901 to 2000. The data processing approach is based on two methodologies: a time-gliding extreme value analysis and a structure-oriented time-series analysis. The results show a significant increase of very hot months and at the same time a decrease of extreme cold months within the 20th century. In the time period after 1951 the probability of very high daily maximum temperatures increased for all seasons. Concerning the precipitation the increase of extreme values and higher variabilities are observed for the winter period. The results concerning the wind are not so clear. Summarizing the extreme behavior of temperature and precipitation has shown strong variations during the last century.

  18. Event Management for Teacher-Coaches: Risk and Supervision Considerations for School-Based Sports

    Science.gov (United States)

    Paiement, Craig A.; Payment, Matthew P.

    2011-01-01

    A professional sports event requires considerable planning in which years are devoted to the success of that single activity. School-based sports events do not have that luxury, because high schools across the country host athletic events nearly every day. It is not uncommon during the fall sports season for a combination of boys' and girls'…

  19. Cold water injection nozzles

    International Nuclear Information System (INIS)

    Kura, Masaaki; Maeda, Masamitsu; Endo, Takio.

    1979-01-01

    Purpose: To inject cold water in a reactor without applying heat cycles to a reactor container and to the inner wall of a feedwater nozzle by securing a perforated plate at the outlet of the cold water injection nozzle. Constitution: A disc-like cap is secured to the final end of a return nozzle of a control rod drive. The cap prevents the flow of a high temperature water flowing downward in the reactor from entering into the nozzle. The cap is perforated with a plurality of bore holes for injecting cold water into the reactor. The cap is made to about 100 mm in thickness so that the cold water passing through the bore holes is heated by the heat conduction in the cap. Accordingly, the flow of high temperature water flowing downwardly in the reactor is inhibited by the cap from backward flowing into the nozzle. Moreover, the flow of the cold water in the nozzle is controlled and rectified when passed through the bore holes in the cap and then injected into the reactor. (Yoshino, Y.)

  20. Development of cold neutron spectrometers

    International Nuclear Information System (INIS)

    Lee, Changhee; Lee, C. H.; So, J. Y.; Park, S.; Han, Y. S.; Cho, S. J.; Moon, M. K.; Choi, Y. H.; Sun, G. M.

    2012-03-01

    Cold Neutron Triple Axsis Spectrometer (Cold-TAS) Development Ο Fabrication and Installation of the Major Cold-TAS Components Ο Performance Test of the Cold-TAS □ Cold Neutron Time-of-Flight Spectrometer(DC-TOF) Development Ο Fabrication of the Major DC-TOF Components Ο Development DC-TOF Data Reduction Software □ Expected Contribution The two world-class inelastic neutron scattering instruments measure atomic or molecular scale dynamics of meV energy range. This unprecedented measurement capability in the country will enable domestic and international scientists to observe new phenomena in their materials research to obtain world class results. Especially those who work in the fields of magnetic properties of superconductors and multiferroics, molecular dynamics, etc. will get more benefit from these two instruments

  1. Observations of cold antihydrogen

    CERN Document Server

    Tan, J N; Gabrielse, G; Oxley, P; Speck, A; Storry, C H; Wessels, M; Grzonka, D; Oelert, W; Schepers, G; Sefzick, T; Walz, J; Pittner, H; Hänsch, T W; Hessels, E A

    2004-01-01

    ATRAP's e/sup +/ cooling of p in a nested Penning trap has led to reports of cold H produced during such cooling by the ATHENA and ATRAP collaborations. To observe H, ATHENA uses coincident annihilation detection and ATRAP uses field ionization followed by p storage. Advantages of ATRAP's field ionization method include the complete absence of any background events, and the first way to measure which H states are produced. ATRAP enhances the H production rate by driving many cycles of e/sup +/ cooling in the nested trap, with more H counted in an hour than the sum of all the other antimatter atoms ever reported. The number of H counted per incident high energy p is also higher than ever observed. The first measured distribution of H states is made using a pre-ionizing electric field between separated production and detection regions. The high rate and the high Rydberg states suggest that the H is formed via three-body recombination, as expected. (22 refs).

  2. Seasonal water mass distribution in the Indonesian throughflow entering the Indian Ocean

    OpenAIRE

    Coatanoan, Christine; Metzl, N; Fieux, M; Coste, B

    1999-01-01

    A multiparametric approach is used to analyze the seasonal properties of water masses in the eastern Indian Ocean. The data were measured during two cruises of the Java Australia Dynamic Experiment (JADE) program carried out during two opposite seasons: August 1989 (SE monsoon) and February-March 1992 (NW monsoon). These cruises took place at the end of a La Nina event and during an EI. Nino episode, respectively. Seven sources have been identified in the studied region for the 200-800 m laye...

  3. Cold perception and gene expression differ in Olea europaea seed coat and embryo during drupe cold acclimation.

    Science.gov (United States)

    D'Angeli, S; Falasca, G; Matteucci, M; Altamura, M M

    2013-01-01

    FAD2 and FAD7 desaturases are involved in cold acclimation of olive (Olea europaea) mesocarp. There is no research information available on cold acclimation of seeds during mesocarp cold acclimation or on differences in the cold response of the seed coat and embryo. How FAD2 and FAD7 affect seed coat and embryo cold responses is unknown. Osmotin positively affects cold acclimation in olive tree vegetative organs, but its role in the seeds requires investigation. OeFAD2.1, OeFAD2.2, OeFAD7 and Oeosmotin were investigated before and after mesocarp acclimation by transcriptomic, lipidomic and immunolabelling analyses, and cytosolic calcium concentration ([Ca(2+)](cyt)) signalling, F-actin changes and seed development were investigated by epifluorescence/histological analyses. Transient [Ca(2+)](cyt) rises and F-actin disassembly were found in cold-shocked protoplasts from the seed coat, but not from the embryo. The thickness of the outer endosperm cuticle increased during drupe exposure to lowering of temperature, whereas the embryo protoderm always lacked cuticle. OeFAD2 transcription increased in both the embryo and seed coat in the cold-acclimated drupe, but linoleic acid (i.e. the product of FAD2 activity) increased solely in the seed coat. Osmotin was immunodetected in the seed coat and endosperm of the cold-acclimated drupe, and not in the embryo. The results show cold responsiveness in the seed coat and cold tolerance in the embryo. We propose a role for the seed coat in maintaining embryo cold tolerance by increasing endosperm cutinization through FAD2 and osmotin activities. © 2012 The Authors. New Phytologist © 2012 New Phytologist Trust.

  4. Cold fusion research

    International Nuclear Information System (INIS)

    1989-11-01

    I am pleased to forward to you the Final Report of the Cold Fusion Panel. This report reviews the current status of cold fusion and includes major chapters on Calorimetry and Excess Heat, Fusion Products and Materials Characterization. In addition, the report makes a number of conclusions and recommendations, as requested by the Secretary of Energy

  5. COLD-WORKED HARDWARE

    Directory of Open Access Journals (Sweden)

    N. M. Strizhak

    2007-01-01

    Full Text Available The different types of cold-worked accessory are examined in the article. The necessity of development of such type of accessory in the Republic of Belarus due to requirements of market is shown. High emphasis is placed on the methods of increase of plasticity of cold-worked accessory from usual mill of RUP and CIS countries.

  6. Present and past Gulf Stream variability in a cold-water coral area off Cape Lookout, West Atlantic

    Science.gov (United States)

    Mienis, F.; Pedersen, A.; Duineveld, G.; Seidenkrantz, M.; Fischel, A.; Matos, L.; Bane, J. M.; Frank, N.; Hebbeln, D.; Ross, S.

    2012-12-01

    Cold-water coral mounds are common on the SE slope of the US from Florida to Cape Hatteras between depths of 400-600 m. All coral areas lie in the vicinity of the Gulf Stream, which is characterized by strong currents transporting relatively warm water northwards. Thus far little is known about the recent and past environmental conditions inside the cold-water coral habitats on the SE US slope and particularly the effect of changing patterns of the Gulf Stream. Near Cape Lookout, which is the northern most cold-water coral area on the SE US slope, cold-water corals have formed mounds up to 60 m high with a tear drop shape, which are oriented in a SSW-NNE direction. Past explorations of major reef sites of N Carolina using remote and manned submersibles have shown living Lophelia pertusa colonies on the current facing side of the mound structures and a high biodiversity of associated fauna, especially fish. Two autonomous benthic landers were deployed amidst Lophelia reefs off Cape Lookout (NC) for a period of 6 months to define oceanographic patterns that are relevant for the development and persistence of cold-water coral ecosystems. Furthermore, a 3.6 m long piston core was collected in 2010 during a cruise with the R.V. Pelagia. This pistoncore was used to determine the changes of current strength through time, using foraminiferal counts, stable oxygen and carbon isotopes on foraminifera, XRF and magnetic susceptibility measurements. Cold-water coral fragments were dated with U/Th and foraminifera from the same depth interval were dated with C14. Bottom landers have recorded a number of events that are characterized by of peaks in temperature and salinity, coinciding with increased flow and turbidity. The current during these events was directed to the NNE. During some of these events temperature rose up to 9 degrees in one day. The temporary replacement of the colder bottom water by warm (and saline) water in combination with the strong currents to the NNE

  7. Role of PPARα in the Control of Torpor through FGF21-NPY Pathway: From Circadian Clock to Seasonal Change in Mammals

    Directory of Open Access Journals (Sweden)

    Norio Ishida

    2009-01-01

    Full Text Available In nature, hibernating animals encounter fasting, cold temperature and short day seasonally. Torpor is a state of decreased physiological activity in an animal, usually characterized by a reduced body temperature and rate of metabolism to adapt such a severe environment. Ablation of the central clock synchronizer, the suprachiasmatic nucleus in brain, abolishes torpor, a hibernation-like state, implicating the circadian clock involved in this seasonal change. Biologists knows well the energy source of daily heterotherms/hibernators changed from glucose to lipids in winter. Here we review several lines of evidence of a master transcriptional regulator in lipid catabolism, PPARα, in the control of torpor through FGF21-NPY pathway. This indicate the importance of circadian—and photoperiod—regulation of PPARα to tell seasons in our body.

  8. Diurnal and seasonal variations of concentration and size distribution of nano aerosols (10-1100 nm) enclosing radon decay products in the Postojna Cave, Slovenia

    International Nuclear Information System (INIS)

    Bezek, M.; Gregoric, A.; Kavasi, N.; Vaupotic, J.

    2012-01-01

    At the lowest point along the tourist route in the Postojna Cave, the activity concentration of radon ( 222 Rn) short-lived decay products and number concentration and size distribution of background aerosol particles in the size range of 10-1100 nm were measured. In the warm yearly season, aerosol concentration was low (52 cm -3 ) with 21 % particles smaller than 50 nm, while in the cold season, it was higher (1238 cm -3 ) with 8 % of -3 , and fractions of unattached radon decay products were 0.62 and 0.13, respectively. (authors)

  9. Spatiotemporal distribution characteristics and attribution of extreme regional low temperature event

    International Nuclear Information System (INIS)

    Feng Tai-Chen; Zhang Ke-Quan; Wang Xiao-Juan; Zhang Wen-Yu; Su Hai-Jing; Gong Zhi-Qiang

    2015-01-01

    Based on an objective identification technique for regional low temperature event (OITRLTE), the daily minimum temperature in China has been detected from 1960 to 2013. During this period, there were 60 regional extreme low temperature events (ERLTEs), which are included in the 690 regional low temperature events (RLTEs). The 60 ERLTEs are analyzed in this paper. The results show that in the last 50 years, the intensity of the ERLTEs has become weak; the number of lasted days has decreased; and, the affected area has become small. However, that situation has changed in this century. In terms of spatial distribution, the high intensity regions are mainly in Northern China while the high frequency regions concentrate in Central and Eastern China. According to the affected area of each event, the 60 ERLTEs are classified into six types. The atmospheric circulation background fields which correspond to these types are also analyzed. The results show that, influenced by stronger blocking highs of Ural and Lake Baikal, as well as stronger southward polar vortex and East Asia major trough at 500-hPa geopotential height, cold air from high latitudes is guided to move southward and abnormal northerly winds at 850 hPa makes the cold air blow into China along diverse paths, thereby forming different types of regional extreme low temperatures in winter. (paper)

  10. Working in the Cold

    Centers for Disease Control (CDC) Podcasts

    During the winter, many workers are outdoors, working in cold, wet, icy, or snowy conditions. Learn how to identify symptoms that tell you there may be a problem and protect yourself from cold stress.

  11. Teleconnections associated with the intensification of the Australian monsoon during El Nino Modoki events

    International Nuclear Information System (INIS)

    Taschetto, A S; Gupta, A Sen; Ummenhofer, C C; England, M H; Haarsma, R J

    2010-01-01

    In this study we investigate the teleconnection between the central-western Pacific sea surface temperature (SST) warming, characteristic of El Nino Modoki events, and Australian rainfall using observations and atmospheric general circulation model experiments. During Modoki events, wet conditions are generally observed over northwestern Australia at the peak of the monsoon season (i.e. January and February) while dry conditions occur in the shoulder-months (i.e. December and March). This results in a shorter but more intense monsoon season over northwestern Australia relative to the climatology. We show that, apart from the well-known displacement of the Walker circulation, the anomalous warming in the central-western equatorial Pacific also induces a westward-propagating disturbance associated with a Gill-type mechanism. This in turn generates an anomalous cyclonic circulation over northwestern Australia that reinforces the climatological mean conditions during the peak of the monsoon season. The anomalous circulation leads to convergence of moisture and increased precipitation over northern Australia. This response, however, only occurs persistently during austral summer when the South Pacific Convergence Zone is climatologically strengthened, phase-locking the Gill-type response to the seasonal cycle. The interaction between the interannual SST variability during El Nino Modoki events and the evolution of the seasonal cycle intensifies deep convection in the central-west Pacific, driving a Gill-type response to diabatic heating. The intensified monsoonal rainfall occurs strongly in February due to the climatological wind conditions that are normally cyclonic over northwestern Australia.

  12. Overexpression of a peach CBF gene in apple: a model for understanding the integration of growth, dormancy, and cold hardiness in woody plants

    Science.gov (United States)

    The timing of cold acclimation and de-acclimation, dormancy, and bud break play an integral role in the life cycle of woody plants. The molecular events that regulate these parameters have been the subject of much study, however, in most studies these events have been investigated independently of ...

  13. Changing seasonality of Arctic hydrology disrupts key biotic linkages in Arctic aquatic ecosystems.

    Science.gov (United States)

    Deegan, L.; MacKenzie, C.; Peterson, B. J.; Fishscape Project

    2011-12-01

    Arctic grayling (Thymallus arcticus) is an important circumpolar species that provide a model system for understanding the impacts of changing seasonality on arctic ecosystem function. Grayling serve as food for other biota, including lake trout, birds and humans, and act as top-down controls in stream ecosystems. In Arctic tundra streams, grayling spend their summers in streams but are obligated to move back into deep overwintering lakes in the fall. Climatic change that affects the seasonality of river hydrology could have a significant impact on grayling populations: grayling may leave overwintering lakes sooner in the spring and return later in the fall due to a longer open water season, but the migration could be disrupted by drought due to increased variability in discharge. In turn, a shorter overwintering season may impact lake trout dynamics in the lakes, which may rely on the seasonal inputs of stream nutrients in the form of migrating grayling into these oligotrophic lakes. To assess how shifting seasonality of Arctic river hydrology may disrupt key trophic linkages within and between lake and stream components of watersheds on the North Slope of the Brooks Mountain Range, Alaska, we have undertaken new work on grayling and lake trout population and food web dynamics. We use Passive Integrated Transponder (PIT) tags coupled with stream-width antenna units to monitor grayling movement across Arctic tundra watersheds during the summer, and into overwintering habitat in the fall. Results indicate that day length may prime grayling migration readiness, but that flooding events are likely the cue grayling use to initiate migration in to overwintering lakes. Many fish used high discharge events in the stream as an opportunity to move into lakes. Stream and lake derived stable isotopes also indicate that lake trout rely on these seasonally transported inputs of stream nutrients for growth. Thus, changes in the seasonality of river hydrology may have broader

  14. Preliminary analysis of beam trip and beam jump events in an ADS prototype

    International Nuclear Information System (INIS)

    D'Angelo, A.; Bianchini, G.; Carta, M.

    2001-01-01

    A core dynamics analysis relevant to some typical current transient events has been carried out on an 80 MW energy amplifier prototype (EAP) fuelled by mixed oxides and cooled by lead-bismuth. Fuel and coolant temperature trends relevant to recovered beam trip and beam jump events have been preliminary investigated. Beam trip results show that the drop in temperature of the core outlet coolant would be reduced a fair amount if the beam intensity could be recovered within few seconds. Due to the low power density in the EAP fuel, the beam jump from 50% of the nominal power transient evolves benignly. The worst thinkable current transient, beam jump with cold reactor, mainly depends on the coolant flow conditions. In the EAP design, the primary loop coolant flow is assured by natural convection and is enhanced by a particular system of cover gas injection into the bottom part of the riser. If this system of coolant flow enhancement is assumed in function, even the beam jump with cold reactor event evolves without severe consequences. (authors)

  15. Major differences observed in transcript profiles of blueberry during cold acclimation under field and cold room conditions.

    Science.gov (United States)

    Dhanaraj, Anik L; Alkharouf, Nadim W; Beard, Hunter S; Chouikha, Imed B; Matthews, Benjamin F; Wei, Hui; Arora, Rajeev; Rowland, Lisa J

    2007-02-01

    Our laboratory has been working toward increasing our understanding of the genetic control of cold hardiness in blueberry (Vaccinium section Cyanococcus) to ultimately use this information to develop more cold hardy cultivars for the industry. Here, we report using cDNA microarrays to monitor changes in gene expression at multiple times during cold acclimation under field and cold room conditions. Microarrays contained over 2,500 cDNA inserts, approximately half of which had been picked and single-pass sequenced from each of two cDNA libraries that were constructed from cold acclimated floral buds and non-acclimated floral buds of the fairly cold hardy cv. Bluecrop (Vaccinium corymbosum L.). Two biological samples were examined at each time point. Microarray data were analyzed statistically using t tests, ANOVA, clustering algorithms, and online analytical processing (OLAP). Interestingly, more transcripts were found to be upregulated under cold room conditions than under field conditions. Many of the genes induced only under cold room conditions could be divided into three major types: (1) genes associated with stress tolerance; (2) those that encode glycolytic and TCA cycle enzymes, and (3) those associated with protein synthesis machinery. A few of the genes induced only under field conditions appear to be related to light stress. Possible explanations for these differences are discussed in physiological context. Although many similarities exist in how plants respond during cold acclimation in the cold room and in the field environment, there are major differences suggesting caution should be taken in interpreting results based only on artificial, cold room conditions.

  16. Ground water heat pumps and cooling with ground water basins as seasonal storage; Grundvandsvarmepumper og -koeling med grundvandsmagasiner som saesonlager

    Energy Technology Data Exchange (ETDEWEB)

    2008-04-15

    Ground water temperature is constant all the year round, in Denmark approximately 9 deg. C, which is ideal for a number of cooling purposes including cooling of buildings. The structures in which the ground water flows (sand, gravel and chalk) are efficient for storing coldness and heat over longer periods. By using seasonal storage of low-temperature heat and coldness in ground water layers close to the terrain it is feasible to reach profitable energy savings of up to 90% for cooling and heating of e.g. hotels, airports, shopping malls, office buildings and other larger buildings. At the same time the large energy savings means major reduction of CO{sub 2} emissions. (BA)

  17. Dependence of present and future European heat waves and cold spells on the location of atmospheric blocking

    Science.gov (United States)

    Brunner, L.; Schaller, N.; Sillmann, J.; Steiner, A. K.

    2017-12-01

    Atmospheric blocking describes stationary anti-cyclones, which weaken or reverse the climatological flow at mid-latitudes. In the northern hemisphere one of the main blocking regions is located over the North Atlantic and Northern Europe. The link between blocking and European temperature extremes, such as heat waves and cold spells, strongly depends on several aspects like season, longitudinal location of the block, and location of the extremes (particularly Northern Europe versus Southern Europe). We use a 50-member ensemble of the Canadian CanESM2 model to investigate historical (1981-2010) and future (2070-2099) blocking cases and their relationship with European temperature extremes. For the historical period the model results are also compared to those from the ERA-Interim reanalysis. Atmospheric blocking is detected on a daily basis in different 30° longitude windows between 60°W and 60°E, using a standard geopotential height-based detection index. Temperature extremes are defined by the daily Heat/Cold Wave Magnitude Index (HWMId/CWMId). The role of cold advection is found particularly important in winter conditions leading to a more than threefold increase in cold wave occurrence during blocking between 60°W and 0°. During blocking over Northern Europe (0° to 60°E) a split relationship is found with cold wave occurrence being strongly increased in Southern Europe, while it is decreased in Northern Europe. Direct, radiative effects dominate in summer, therefore blocking westward of Europe has a weaker effect, while blocking over Northern Europe leads to an increase of heat waves by at least a factor three at the location of the block and a decrease in cold wave occurrence in almost all of Europe. Comparing the historical and future period we find the link between blocking and temperature extremes in Europe to be robust, even though blocking frequency and temperatures are changing.

  18. Effects of cold temperatures on the excitability of rat trigeminal ganglion neurons that are not for cold sensing.

    Science.gov (United States)

    Kanda, Hirosato; Gu, Jianguo G

    2017-05-01

    Aside from a small population of primary afferent neurons for sensing cold, which generate sensations of innocuous and noxious cold, it is generally believed that cold temperatures suppress the excitability of primary afferent neurons not responsible for cold sensing. These not-for-cold-sensing neurons include the majority of non-nociceptive and nociceptive afferent neurons. In this study we have found that the not-for-cold-sensing neurons of rat trigeminal ganglia (TG) change their excitability in several ways at cooling temperatures. In nearly 70% of not-for-cold-sensing TG neurons, a cooling temperature of 15°C increases their membrane excitability. We regard these neurons as cold-active neurons. For the remaining 30% of not-for-cold-sensing TG neurons, the cooling temperature of 15°C either has no effect (cold-ineffective neurons) or suppress their membrane excitability (cold-suppressive neurons). For cold-active neurons, the cold temperature of 15°C increases their excitability as is evidenced by increases in action potential (AP) firing numbers and/or the reduction in AP rheobase when these neurons are depolarized electrically. The cold temperature of 15°C significantly inhibits M-currents and increases membrane input resistance of cold-active neurons. Retigabine, an M-current activator, abolishes the effect of cold temperatures on AP firing, but not the effect of cold temperature on AP rheobase levels. The inhibition of M-currents and the increases of membrane input resistance are likely two mechanisms by which cooling temperatures increase the excitability of not-for-cold-sensing TG neurons. This article is part of the special article series "Pain". © 2015 International Society for Neurochemistry.

  19. Impairment of exercise performance following cold water immersion is not attenuated after 7 days of cold acclimation.

    Science.gov (United States)

    Jones, Douglas M; Roelands, Bart; Bailey, Stephen P; Buono, Michael J; Meeusen, Romain

    2018-03-19

    It is well-documented that severe cold stress impairs exercise performance. Repeated immersion in cold water induces an insulative type of cold acclimation, wherein enhanced vasoconstriction leads to greater body heat retention, which may attenuate cold-induced exercise impairments. The purpose of this study, therefore, was to investigate changes in exercise performance during a 7-day insulative type of cold acclimation. Twelve healthy participants consisting of eight males and four females (mean ± SD age: 25.6 ± 5.2 years, height: 174.0 ± 8.9 cm, weight: 75.6 ± 13.1 kg) performed a 20 min self-paced cycling test in 23 °C, 40% humidity without prior cold exposure. Twenty-four hours later they began a 7-day cold acclimation protocol (daily 90 min immersion in 10 °C water). On days one, four, and seven of cold acclimation, participants completed the same cycling test. Measurements of work completed, core and skin temperatures, heart rate, skin blood flow, perceived exertion, and thermal sensation were measured during each cycling test. Successful insulative cold acclimation was observed. Work produced during the baseline cycling test (220 ± 70 kJ) was greater (p immersions (195 ± 58, 197 ± 60, and 194 ± 62 kJ) despite similar ratings of perceived exertion during each test, suggesting that cold exposure impaired cycling performance. This impairment, however, was not attenuated over the cold acclimation period. Results suggest that insulative cold acclimation does not attenuate impairments in exercise performance that were observed following acute cold water immersion.

  20. Plaadid / Katrin Malt, Virko Pirrus, Mart Kalvet

    Index Scriptorium Estoniae

    Malt, Katrin

    2008-01-01

    Uutest heliplaatidest Atrocity "Werk 80 II", Benighted "Icon", Brain Drill "Apocalyptic Feasting", BrainStorm "Downburst", Diablo Swing Orchestra "The Butcher's Ballroom", Floodstain "Dreams Make Monters", Foxy Shazam "Introducting Foxy Shazam"