WorldWideScience

Sample records for winter months model

  1. GLOBAL DECREASES IN TOTAL OZONE DURING THE WINTER MONTHS

    OpenAIRE

    タカオ, トシノリ; Toshinori, TAKAO

    1990-01-01

    Global network of total ozone measurements by Dobson spectrophotometer shows ozone decrease in recent years. At midlatitudes of the Northern Hemisphere, ozone loss was significant during the winter months of 1983 and 1985. In some regions, there is a positive correlation between the annual mean of total ozone amounts and the solar cycle.

  2. Testing efficacy of monthly forecast application in agrometeorology: Winter wheat phenology dynamic

    Science.gov (United States)

    Lalic, B.; Jankovic, D.; Dekic, Lj; Eitzinger, J.; Firanj Sremac, A.

    2017-02-01

    Use of monthly weather forecast as input meteorological data for agrometeorological forecasting, crop modelling and plant protection can foster promising applications in agricultural production. Operational use of monthly or seasonal weather forecast can help farmers to optimize field operations (fertilizing, irrigation) and protection measures against plant diseases and pests by taking full advantage of monthly forecast information in predicting plant development, pest and disease risks and yield potentials few weeks in advance. It can help producers to obtain stable or higher yield with the same inputs and to minimise losses caused by weather. In Central and South-Eastern Europe ongoing climate change lead to shifts of crops phenology dynamics (i.e. in Serbia 4-8 weeks earlier in 2016 than in previous years) and brings this subject in the front of agronomy science and practice. Objective of this study is to test efficacy of monthly forecast in predicting phenology dynamics of different winter wheat varieties, using phenological model developed by Forecasting and Warning Service of Serbia in plant protection. For that purpose, historical monthly forecast for four months (March 1, 2005 - June 30, 2005) was assimilated from ECMWF MARS archive for 50 ensemble members and control run. Impact of different agroecological conditions is tested by using observed and forecasted data for two locations - Rimski Sancevi (Serbia) and Groß-Enzersdorf (Austria).

  3. Risk management model of winter navigation operations.

    Science.gov (United States)

    Valdez Banda, Osiris A; Goerlandt, Floris; Kuzmin, Vladimir; Kujala, Pentti; Montewka, Jakub

    2016-07-15

    The wintertime maritime traffic operations in the Gulf of Finland are managed through the Finnish-Swedish Winter Navigation System. This establishes the requirements and limitations for the vessels navigating when ice covers this area. During winter navigation in the Gulf of Finland, the largest risk stems from accidental ship collisions which may also trigger oil spills. In this article, a model for managing the risk of winter navigation operations is presented. The model analyses the probability of oil spills derived from collisions involving oil tanker vessels and other vessel types. The model structure is based on the steps provided in the Formal Safety Assessment (FSA) by the International Maritime Organization (IMO) and adapted into a Bayesian Network model. The results indicate that ship independent navigation and convoys are the operations with higher probability of oil spills. Minor spills are most probable, while major oil spills found very unlikely but possible. Copyright © 2016 The Authors. Published by Elsevier Ltd.. All rights reserved.

  4. Southern Ocean monthly wave fields for austral winters 1985-1988 by Geosat radar altimeter

    Science.gov (United States)

    Josberger, E.G.; Mognard, N.M.

    1996-01-01

    Four years of monthly averaged wave height fields for the austral winters 19851988 derived from the Geosat altimeter data show a spatial variability of the scale of 500-1000 km that varies monthly and annually. This variability is superimposed on the zonal patterns surrounding the Antarctic continent and characteristic of the climatology derived from the U.S. Navy [1992] Marine Climatic Atlas of the World. The location and the intensity of these large-scale features, which are not found in the climatological fields, exhibit strong monthly and yearly variations. A global underestimation of the climatological mean wave heights by more than l m is also found over large regions of the Southern Ocean. The largest monthly averaged significant wave heights are above 5 m and are found during August of every year in the Indian Ocean, south of 40??S. The monthly wave fields show more variability in the Atlantic and Pacific Oceans than in the Indian Ocean. The Seasat data from 1978 and the Geosat data from 1985 and 1988 show an eastward rotation of the largest wave heights. However, this rotation is absent in 1986 and 1987; the former was a year of unusually low sea states, and the latter was a year of unusually high sea states, which suggests a link to the El Nin??o-Southern Oscillation event of 1986. Copyright 1996 by the American Geophysical Union.

  5. Social, Occupational, and Cultural Adaptation During a 12-Month Wintering in Antarctica.

    Science.gov (United States)

    Nicolas, Michel; Bishop, Sheryl L; Weiss, Karine; Gaudino, Marvin

    2016-09-01

    Life in isolated and confined environments (ICEs) is subject to important constraints which can generate psychosociologically impaired outcomes. This study investigated psychological, social, occupational, and cultural variables which are among the most important determinants in adaptation to a one-year wintering in Antarctica for 13 international subjects. Our findings confirm and give further insight into the role of social (Cohesiveness, Social Support) and occupational (Implementation/Preparedness, Counterproductive Activity, Decision Latitude, and Psychological Job Demands) dimensions of adaptation to ICEs. Relationships between various social and occupational dimensions studies reflected detrimental effects ranging from decrements in cohesiveness (ICE 1, M = 4.44; ICE 7, M = 3.33), social support (ICE 2, M = 4.93; ICE 7, M = 4.28), and work performance (ICE 1, M = 4.33; ICE 6, M = 3.5), which differed across professional status and multicultural factors. These psychosocial issues have important implications for pre-mission selection and training, monitoring and support of crews during the mission, and post-mission readaptation. Operational recommendations are suggested to improve adaptation, success, and well-being for long-duration ICE missions, e.g., to Mars and beyond. Nicolas M, Bishop SL, Weiss K, Gaudino M. Social, occupational, and cultural adaptation during a 12-month wintering in Antarctica. Aerosp Med Hum Perform. 2016; 87(9):781-789.

  6. Contribution of Leaf Litter to Nutrient Export during Winter Months in an Urban Residential Watershed.

    Science.gov (United States)

    Bratt, Anika R; Finlay, Jacques C; Hobbie, Sarah E; Janke, Benjamin D; Worm, Adam C; Kemmitt, Kathrine L

    2017-03-21

    Identification of nonpoint sources of nitrogen (N) and phosphorus (P) in urban systems is imperative to improving water quality and better managing eutrophication. Winter contributions and sources of annual N and P loads from urban watersheds are poorly characterized in northern cities because monitoring is often limited to warm-weather periods. To determine the winter export of N and P, we monitored stormwater outflow in a residential watershed in Saint Paul, Minnesota during 2012-2014. Our data demonstrate that winter melt events contribute a high percentage of annual N and P export (50%). We hypothesized that overwintering leaf litter that is not removed by fall street sweeping could be an important source to winter loads of N and P. We estimated contributions of this source by studying decomposition in lawns, street gutters, and catch basins during two winters. Rates of mass and N loss were negligible during both winters. However, P was quickly solubilized from decomposing leaves. Using mass balances and estimates of P leaching losses, we estimated that leaf litter could contribute 80% of winter total dissolved phosphorus (TDP) loading in this watershed (∼40% of annual TDP loading). Our work indicates that urban trees adjacent to streets likely represent a major source of P pollution in northern cities. Management that targets important winter sources such as tree leaves could be highly effective for reducing P loading and may mitigate eutrophication in urban lakes and streams in developed cities.

  7. Representing winter wheat in the Community Land Model (version 4.5)

    Science.gov (United States)

    Lu, Yaqiong; Williams, Ian N.; Bagley, Justin E.; Torn, Margaret S.; Kueppers, Lara M.

    2017-05-01

    Winter wheat is a staple crop for global food security, and is the dominant vegetation cover for a significant fraction of Earth's croplands. As such, it plays an important role in carbon cycling and land-atmosphere interactions in these key regions. Accurate simulation of winter wheat growth is not only crucial for future yield prediction under a changing climate, but also for accurately predicting the energy and water cycles for winter wheat dominated regions. We modified the winter wheat model in the Community Land Model (CLM) to better simulate winter wheat leaf area index, latent heat flux, net ecosystem exchange of CO2, and grain yield. These included schemes to represent vernalization as well as frost tolerance and damage. We calibrated three key parameters (minimum planting temperature, maximum crop growth days, and initial value of leaf carbon allocation coefficient) and modified the grain carbon allocation algorithm for simulations at the US Southern Great Plains ARM site (US-ARM), and validated the model performance at eight additional sites across North America. We found that the new winter wheat model improved the prediction of monthly variation in leaf area index, reduced latent heat flux, and net ecosystem exchange root mean square error (RMSE) by 41 and 35 % during the spring growing season. The model accurately simulated the interannual variation in yield at the US-ARM site, but underestimated yield at sites and in regions (northwestern and southeastern US) with historically greater yields by 35 %.

  8. High resolution reconstruction of monthly autumn and winter precipitation of Iberian Peninsula for last 150 years.

    Science.gov (United States)

    Cortesi, N.; Trigo, R.; González-Hidalgo, J. C.; Ramos, A.

    2012-04-01

    Precipitation over Iberian Peninsula (IP) presents large values of interannual variability and large spatial contrasts between wet mountainous regions in the north and dry regions in the southern plains. Unlike other European regions, IP was poorly monitored for precipitation during 19th century. Here we present a new approach to fill this gap. A set of 26 atmospheric circulation weather types (Trigo R.M. and DaCamara C.C., 2000) derived from a recent SLP dataset, the EMULATE (European and North Atlantic daily to multidecadal climate variability) Project, was used to reconstruct Iberian monthly precipitation from October to March during 1851-1947. Principal Component Regression Analysis was chosen to develop monthly precipitation reconstruction back to 1851 and calibrated over 1948-2003 period for 3030 monthly precipitation series of high-density homogenized MOPREDAS (Monthly Precipitation Database for Spain and Portugal) database. Validation was conducted over 1920-1947 at 15 key site locations. Results show high model performance for selected months, with a mean coefficient of variation (CV) around 0.6 during validation period. Lower CV values were achieved in western area of IP. Trigo, R. M., and DaCamara, C.C., 2000: "Circulation weather types and their impact on the precipitation regime in Portugal". Int. J. Climatol., 20, 1559-1581.

  9. Human adaptation to isolated and confined environments: Preliminary findings of a seven month Antarctic winter-over human factors study

    Science.gov (United States)

    Evans, Gary W.; Stokols, Daniel; Carrere, Sybil

    1988-01-01

    This field study was conducted during the last decade of an austral winter-over at Palmer Station in the Antarctic. The purpose of the study was to understand temporal patterns in physiological arousal and psychological mood over the course of the mission. The investigators were principally interested in how people adapted over time to chronic and acute stressors, and how people use and modify their built environment. Physiological and psychological data were collected several times a week, and information on behavior and the use of physical facilities was collected monthly. Physiological and psychological data were compared with social changes in the setting toward the development of a sequential model of human-environment transactional relationships. Based on the study results, guidelines for design of future isolated and confined environments (ICEs) included: plan space for items which make people feel at home, provide materials to allow people to personalize their environment, allow for flexible environments, provide areas for visual and auditory privacy, equip areas for socializing and remove them from private areas, and provide facilities for exercise and for projects involving physical activity. The study offers guidelines about patterns of adaption that could be expected in an ICE, discusses how these settings can be programmed to facilitate successful adjustment, and provides information about how to design future ICE habitats to maximize a healthy living environment.

  10. Infective respiratory syncytial virus is present in human cord blood samples and most prevalent during winter months.

    Directory of Open Access Journals (Sweden)

    Angela Mary Fonceca

    Full Text Available Human respiratory syncytial virus (RSV remains the most common cause of severe lower respiratory tract disease amongst infants, and continues to cause annual epidemics of respiratory disease every winter worldwide. Demonstrating placental transmission of viable RSV in human samples is a major paradigm shift in respiratory routes considered likely for RSV transmission.Droplet digital PCR (ddPCR was used to identify RSV present in cord blood mononucleocytes (CBM. CBMs testing positive for RSV were treated with phytohemagglutinin (PHA, PHA and nitric oxide (NO or PHA, NO and palivizumab, and co-cultured with HeLa cell monolayers. Subsequent immuno-staining for RSV was used to visualize infective viral plaques.RSV was detected in 26 of 45 samples (57.7% by ddPCR. CBM's collected in winter were more likely to test positive for RSV (17/21 samples, risk = 80%, OR = 7.08; 95% CI 1.80-27.80; p = 0.005 compared to non-winter months (9/24 samples, 37.5%. RSV plaques were observed in non-treated and treated co-cultured HeLa monolayers.Demonstrating active RSV in CBMs suggests in utero transmission of infective virus to the fetus without causing overt disease. This is likely to have an important impact on immune development as well as future virus-host interactions, thereby warranting further investigation.

  11. Infective respiratory syncytial virus is present in human cord blood samples and most prevalent during winter months.

    Science.gov (United States)

    Fonceca, Angela Mary; Chopra, Abha; Levy, Avram; Noakes, Paul Stanton; Poh, Matthew Wee-Peng; Bear, Natasha Leanne; Prescott, Susan; Everard, Mark Lloyd

    2017-01-01

    Human respiratory syncytial virus (RSV) remains the most common cause of severe lower respiratory tract disease amongst infants, and continues to cause annual epidemics of respiratory disease every winter worldwide. Demonstrating placental transmission of viable RSV in human samples is a major paradigm shift in respiratory routes considered likely for RSV transmission. Droplet digital PCR (ddPCR) was used to identify RSV present in cord blood mononucleocytes (CBM). CBMs testing positive for RSV were treated with phytohemagglutinin (PHA), PHA and nitric oxide (NO) or PHA, NO and palivizumab, and co-cultured with HeLa cell monolayers. Subsequent immuno-staining for RSV was used to visualize infective viral plaques. RSV was detected in 26 of 45 samples (57.7%) by ddPCR. CBM's collected in winter were more likely to test positive for RSV (17/21 samples, risk = 80%, OR = 7.08; 95% CI 1.80-27.80; p = 0.005) compared to non-winter months (9/24 samples, 37.5%). RSV plaques were observed in non-treated and treated co-cultured HeLa monolayers. Demonstrating active RSV in CBMs suggests in utero transmission of infective virus to the fetus without causing overt disease. This is likely to have an important impact on immune development as well as future virus-host interactions, thereby warranting further investigation.

  12. Modeling temperature inversion in southeastern Yellow Sea during winter 2016

    Science.gov (United States)

    Pang, Ig-Chan; Moon, Jae-Hong; Lee, Joon-Ho; Hong, Ji-Seok; Pang, Sung-Jun

    2017-05-01

    A significant temperature inversion with temperature differences larger than 3°C was observed in the southeastern Yellow Sea (YS) during February 2016. By analyzing in situ hydrographic profiles and results from a regional ocean model for the YS, this study examines the spatiotemporal evolution of the temperature inversion and its connection with wind-induced currents in winter. Observations reveal that in winter, when the northwesterly wind prevails over the YS, the temperature inversion occurs largely at the frontal zone southwest of Korea where warm/saline water of a Kuroshio origin meets cold/fresh coastal water. Our model successfully captures the temperature inversion observed in the winter of 2016 and suggests a close relation between northwesterly wind bursts and the occurrence of the large inversion. In this respect, the strong northwesterly wind drove cold coastal water southward in the upper layer via Ekman transport, which pushed the water mass southward and increased the sea level slope in the frontal zone in southeastern YS. The intensified sea level slope propagated northward away from the frontal zone as a shelf wave, causing a northward upwind flow response along the YS trough in the lower layer, thereby resulting in the large temperature inversion. Diagnostic analysis of the momentum balance shows that the westward pressure gradient, which developed with shelf wave propagation along the YS trough, was balanced with the Coriolis force in accordance with the northward upwind current in and around the inversion area.

  13. STATISTICAL ANALYSIS OF METEOROLOGICAL FACTORS AND AIR POLLUTION AT WINTER MONTHS IN ELAZIĞ, TURKEY

    Directory of Open Access Journals (Sweden)

    Ebru Akpinar

    2009-06-01

    Full Text Available In the present study, relationship between monitored air pollutant concentrations such as SO2 and the total suspended particles (TSP data and meteorological factors such as wind speed, temperature, relative humidity and atmospheric pressure was investigated in months of October, November, December, January, February, and March during the period of three years (2003, 2004 and 2005 for Elazığ city. According to the results of linear and non-linear regression analysis, it was found that there is a moderate and weak level of relation between the air pollutant concentrations and the meteorological factors in Elazığ city.

  14. STATISTICAL ANALYSIS OF METEOROLOGICAL FACTORS AND AIR POLLUTION AT WINTER MONTHS IN ELAZIG, TURKEY

    Directory of Open Access Journals (Sweden)

    Ebru Kavak Akpinar

    2009-01-01

    Full Text Available In the present study, relationship between monitored air pollutant concentrations such as SO2 and the total suspended particles (TSP data and meteorological factors such as wind speed, temperature, relative humidity and atmospheric pressure was investigated in months of October, November, December, January, February, and March during the period of three years (2003, 2004 and 2005 for Elazg city. According to the results of linear and non-linear regression analysis, it was found that there is a moderate and weak level of relation between the air pollutant concentrations and the meteorological factors in Elazg city.

  15. Clustering of European winter storms: A multi-model perspective

    Science.gov (United States)

    Renggli, Dominik; Buettner, Annemarie; Scherb, Anke; Straub, Daniel; Zimmerli, Peter

    2016-04-01

    The storm series over Europe in 1990 (Daria, Vivian, Wiebke, Herta) and 1999 (Anatol, Lothar, Martin) are very well known. Such clusters of severe events strongly affect the seasonally accumulated damage statistics. The (re)insurance industry has quantified clustering by using distribution assumptions deduced from the historical storm activity of the last 30 to 40 years. The use of storm series simulated by climate models has only started recently. Climate model runs can potentially represent 100s to 1000s of years, allowing a more detailed quantification of clustering than the history of the last few decades. However, it is unknown how sensitive the representation of clustering is to systematic biases. Using a multi-model ensemble allows quantifying that uncertainty. This work uses CMIP5 decadal ensemble hindcasts to study clustering of European winter storms from a multi-model perspective. An objective identification algorithm extracts winter storms (September to April) in the gridded 6-hourly wind data. Since the skill of European storm predictions is very limited on the decadal scale, the different hindcast runs are interpreted as independent realizations. As a consequence, the available hindcast ensemble represents several 1000 simulated storm seasons. The seasonal clustering of winter storms is quantified using the dispersion coefficient. The benchmark for the decadal prediction models is the 20th Century Reanalysis. The decadal prediction models are able to reproduce typical features of the clustering characteristics observed in the reanalysis data. Clustering occurs in all analyzed models over the North Atlantic and European region, in particular over Great Britain and Scandinavia as well as over Iberia (i.e. the exit regions of the North Atlantic storm track). Clustering is generally weaker in the models compared to reanalysis, although the differences between different models are substantial. In contrast to existing studies, clustering is driven by weak

  16. Monthly Water Balance Model Hydrology Futures

    Science.gov (United States)

    Bock, Andy; Hay, Lauren E.; Markstrom, Steven; Atkinson, R. Dwight

    2016-01-01

    A monthly water balance model (MWBM) was driven with precipitation and temperature using a station-based dataset for current conditions (1950 to 2010) and selected statistically-downscaled general circulation models (GCMs) for current and future conditions (1950 to 2099) across the conterminous United States (CONUS) using hydrologic response units from the Geospatial Fabric for National Hydrologic Modeling (http://dx.doi.org/doi:10.5066/F7542KMD). Six MWBM output variables (actual evapotranspiration (AET), potential evapotranspiration (PET), runoff (RO), streamflow (STRM), soil moisture storage (SOIL), and snow water equivalent (SWE)) and the two MWBM input variables (atmospheric temperature (TAVE) and precipitation (PPT)) were summarized for hydrologic response units and aggregated at points of interest on a stream network. Results were then organized into the Monthly Water Balance Hydrology Futures database, an open-access database using netCDF format (http://cida-eros-mows1.er.usgs.gov/thredds/dodsC/nwb_pub/).  Methods used to calibrate and parameterize the MWBM are detailed in the Hydrology and Earth System Sciences (HESS)  paper "Parameter regionalization of a monthly water balance model for the conterminous United States" by Bock and others (2016).  See the discussion paper link in the "Related External Resources" section for access.  Supplemental data files related to the plots and data analysis in Bock and others (2016) can be found in the HESS-2015-325.zip folder in the "Attached Files" section.  Detailed information on the files and data can be found in the ReadMe.txt contained within the zipped folder. Recommended citation of discussion paper:Bock, A.R., Hay, L.E., McCabe, G.J., Markstrom, S.L., and Atkinson, R.D., 2016, Parameter regionalization of a monthly water balance model for the conterminous United States: Hydrology and Earth System Sciences, v. 20, 2861-2876, doi:10.5194/hess-20-2861-2016, 2016

  17. Summer and winter habitat suitability of Marco Polo argali in southeastern Tajikistan: A modeling approach.

    Science.gov (United States)

    Salas, Eric Ariel L; Valdez, Raul; Michel, Stefan

    2017-11-01

    We modeled summer and winter habitat suitability of Marco Polo argali in the Pamir Mountains in southeastern Tajikistan using these statistical algorithms: Generalized Linear Model, Random Forest, Boosted Regression Tree, Maxent, and Multivariate Adaptive Regression Splines. Using sheep occurrence data collected from 2009 to 2015 and a set of selected habitat predictors, we produced summer and winter habitat suitability maps and determined the important habitat suitability predictors for both seasons. Our results demonstrated that argali selected proximity to riparian areas and greenness as the two most relevant variables for summer, and the degree of slope (gentler slopes between 0° to 20°) and Landsat temperature band for winter. The terrain roughness was also among the most important variables in summer and winter models. Aspect was only significant for winter habitat, with argali preferring south-facing mountain slopes. We evaluated various measures of model performance such as the Area Under the Curve (AUC) and the True Skill Statistic (TSS). Comparing the five algorithms, the AUC scored highest for Boosted Regression Tree in summer (AUC = 0.94) and winter model runs (AUC = 0.94). In contrast, Random Forest underperformed in both model runs.

  18. Summer and winter habitat suitability of Marco Polo argali in southeastern Tajikistan: A modeling approach

    Directory of Open Access Journals (Sweden)

    Eric Ariel L. Salas

    2017-11-01

    Full Text Available We modeled summer and winter habitat suitability of Marco Polo argali in the Pamir Mountains in southeastern Tajikistan using these statistical algorithms: Generalized Linear Model, Random Forest, Boosted Regression Tree, Maxent, and Multivariate Adaptive Regression Splines. Using sheep occurrence data collected from 2009 to 2015 and a set of selected habitat predictors, we produced summer and winter habitat suitability maps and determined the important habitat suitability predictors for both seasons. Our results demonstrated that argali selected proximity to riparian areas and greenness as the two most relevant variables for summer, and the degree of slope (gentler slopes between 0° to 20° and Landsat temperature band for winter. The terrain roughness was also among the most important variables in summer and winter models. Aspect was only significant for winter habitat, with argali preferring south-facing mountain slopes. We evaluated various measures of model performance such as the Area Under the Curve (AUC and the True Skill Statistic (TSS. Comparing the five algorithms, the AUC scored highest for Boosted Regression Tree in summer (AUC = 0.94 and winter model runs (AUC = 0.94. In contrast, Random Forest underperformed in both model runs. Keywords: Ecology, Evolution, Zoology, Environmental science, Geography, Biological sciences

  19. Assessing winter cover crop nutrient uptake efficiency using a water quality simulation model

    Science.gov (United States)

    Yeo, In-Young; Lee, Sangchui; Sadeghi, Ali M.; Beeson, Peter C.; Hively, W. Dean; McCarty, Greg W.; Lang, Megan W.

    2013-01-01

    Winter cover crops are an effective conservation management practice with potential to improve water quality. Throughout the Chesapeake Bay Watershed (CBW), which is located in the Mid-Atlantic US, winter cover crop use has been emphasized and federal and state cost-share programs are available to farmers to subsidize the cost of winter cover crop establishment. The objective of this study was to assess the long-term effect of planting winter cover crops at the watershed scale and to identify critical source areas of high nitrate export. A physically-based watershed simulation model, Soil and Water Assessment Tool (SWAT), was calibrated and validated using water quality monitoring data and satellite-based estimates of winter cover crop species performance to simulate hydrological processes and nutrient cycling over the period of 1991–2000. Multiple scenarios were developed to obtain baseline information on nitrate loading without winter cover crops planted and to investigate how nitrate loading could change with different winter cover crop planting scenarios, including different species, planting times, and implementation areas. The results indicate that winter cover crops had a negligible impact on water budget, but significantly reduced nitrate leaching to groundwater and delivery to the waterways. Without winter cover crops, annual nitrate loading was approximately 14 kg ha−1, but it decreased to 4.6–10.1 kg ha−1 with winter cover crops resulting in a reduction rate of 27–67% at the watershed scale. Rye was most effective, with a potential to reduce nitrate leaching by up to 93% with early planting at the field scale. Early planting of winter cover crops (~30 days of additional growing days) was crucial, as it lowered nitrate export by an additional ~2 kg ha−1 when compared to late planting scenarios. The effectiveness of cover cropping increased with increasing extent of winter cover crop implementation. Agricultural fields with well-drained soils

  20. Thermodynamic modelling predicts energetic bottleneck for seabirds wintering in the northwest Atlantic.

    Science.gov (United States)

    Fort, Jérôme; Porter, Warren P; Grémillet, David

    2009-08-01

    Studying the energetics of marine top predators such as seabirds is essential to understand processes underlying adult winter survival and its impact on population dynamics. Winter survival is believed to be the single most important life-history trait in long-lived species but its determinants are largely unknown. Seabirds are inaccessible during this season, so conventional metabolic studies are extremely challenging and new approaches are needed. This paper describes and uses a state-of-the-art mechanistic model, Niche Mapper, to predict energy expenditure and food requirements of the two main seabird species wintering in the northwest Atlantic. We found that energy demand increased throughout the winter phase in both species. Across this period, mean estimated daily energy requirements were 1306 kJ day(-1) for Brünnich's guillemots (Uria lomvia) and 430 kJ day(-1) for little auks (Alle alle) wintering off Greenland and Newfoundland. Mean estimated daily food requirements were 547 g wet food day(-1) for Brünnich's guillemots, and 289 g wet food day(-1) for little auks. For both species and both wintering sites, our model predicts a sharp increase in energy expenditure between November and December, primarily driven by climatic factors such as air temperature and wind speed. These findings strongly suggest the existence of an energetic bottleneck for North Atlantic seabirds towards the end of the year, a challenging energetic phase which might explain recurrent events of winter mass-mortality, so called 'seabird winter wrecks'. Our study therefore emphasizes the relevance of thermodynamics/biophysical modelling for investigating the energy balance of wintering marine top predators and its interplay with survival and population dynamics in the context of global change.

  1. Summer hot snaps and winter conditions: modelling white syndrome outbreaks on Great Barrier Reef corals.

    Directory of Open Access Journals (Sweden)

    Scott F Heron

    Full Text Available Coral reefs are under increasing pressure in a changing climate, one such threat being more frequent and destructive outbreaks of coral diseases. Thermal stress from rising temperatures has been implicated as a causal factor in disease outbreaks observed on the Great Barrier Reef, Australia, and elsewhere in the world. Here, we examine seasonal effects of satellite-derived temperature on the abundance of coral diseases known as white syndromes on the Great Barrier Reef, considering both warm stress during summer and deviations from mean temperatures during the preceding winter. We found a high correlation (r(2 = 0.953 between summer warm thermal anomalies (Hot Snap and disease abundance during outbreak events. Inclusion of thermal conditions during the preceding winter revealed that a significant reduction in disease outbreaks occurred following especially cold winters (Cold Snap, potentially related to a reduction in pathogen loading. Furthermore, mild winters (i.e., neither excessively cool nor warm frequently preceded disease outbreaks. In contrast, disease outbreaks did not typically occur following warm winters, potentially because of increased disease resistance of the coral host. Understanding the balance between the effects of warm and cold winters on disease outbreak will be important in a warming climate. Combining the influence of winter and summer thermal effects resulted in an algorithm that yields both a Seasonal Outlook of disease risk at the conclusion of winter and near real-time monitoring of Outbreak Risk during summer. This satellite-derived system can provide coral reef managers with an assessment of risk three-to-six months in advance of the summer season that can then be refined using near-real-time summer observations. This system can enhance the capacity of managers to prepare for and respond to possible disease outbreaks and focus research efforts to increase understanding of environmental impacts on coral disease in

  2. Evaluation of a monthly hydrological model for Integrated Assessment Models

    Science.gov (United States)

    Liu, Y.; Hejazi, M. I.; Li, H. Y.; Zhang, X.; Leng, G.

    2016-12-01

    The Integrated Assessment modeling (IAM) community, which generated the four representative concentration pathways (RCPs), is actively moving toward including endogenous representations of water supply and demand in their economic modeling frameworks. Toward integrating the water supply module, we build an efficient object-oriented and open-source hydrologic model (HM) to be embedded in IAMs - Global Change Assessment Model (GCAM). The main objective for this new HM is to strike a balance between model complexity and computational efficiency; i.e., possessing sufficient fidelity to capture both the annual and the seasonal signals of water fluxes and pools and being highly computationally efficient so that it can be used for large number of simulations or uncertainty quantification analyses. To this end, we build a monthly gridded hydrological model based on the ABCD model with some additional features such as a snow scheme and the effects of land use and land cover change (LULCC) on the hydrological cycle. In this framework, we mainly simulate the pools of soil moisture, snowpack and groundwater storage, and the fluxes of evapotranspiration, recharge to groundwater, direct runoff and groundwater discharge. We assess the performance of the model by comparing the model results against runoff simulation from the model of Variable Infiltration Capacity (VIC) as well as historical streamflow observations at various gauge stations. We will present results on the model performance, the gains of adding different model components (e.g., snow scheme, effects of LULCC), and the variations of hydrological cycle globally over the historical period of 1901-2010.

  3. Winter precipitation characteristics in western US related to atmospheric river landfalls: observations and model evaluations

    Science.gov (United States)

    Kim, J.; Guan, B.; Waliser, D. E.; Ferraro, R. D.; Case, J. L.; Iguchi, T.; Kemp, E.; Putman, W.; Wang, W.; Wu, D.; Tian, B.

    2018-01-01

    Winter precipitation (PR) characteristics in western United States (WUS) related to atmospheric river (AR) landfalls are examined using the observation-based PRISM data. The observed AR-related precipitation characteristics are in turn used to evaluate model precipitation data from the NASA MERRA2 reanalysis and from seven dynamical downscaling simulations driven by the MERRA2. Multiple metrics including mean bias, Taylor diagram, and two skill scores are used to measure model performance for three climatological sub-regions in WUS, Pacific Northwest (PNW), Pacific Southwest (PSW) and Great Basin (GB). All model data well represent the winter-mean PR with spatial pattern correlations of 0.8 or higher with PRISM for the three sub-regions. Higher spatial resolutions and/or the use of spectral nudging generally yield higher skill scores in simulating the geographical distribution of PR for the entire winter. The PRISM data shows that the AR-related fraction of winter PR and associated daily PR PDFs in each region vary strongly for landfall locations; AR landfalls in the northern WUS coast (NC) affect mostly PNW while those in the southern WUS coast (SC) affect both PSW and GB. NC (SC) landfalls increase the frequency of heavy PR in PNW (PSW and GB) but reduce it in PSW (PNW). All model data reasonably represent these observed variations in the AR-related winter PR fractions and the daily PR PDFs according to AR landfall locations. However, unlike for the entire winter period, no systematic effects of resolution and/or spectral nudging are identified in these AR-related PR characteristics. Dynamical downscaling in this study generally yield positive added values to the MERRA2 PR in the AR-related PR fraction for most sub-regions and landfall locations, most noticeably for PSW by NU-WRF. The downscaling also generate positive added value in p95 for PNW, but negative values for PSW and GB due to overestimation of heavy precipitation events.

  4. A stochastic model of chromatin modification: cell population coding of winter memory in plants.

    Science.gov (United States)

    Satake, Akiko; Iwasa, Yoh

    2012-06-07

    Biological memory, a sustained cellular response to a transient stimulus, has been found in many natural systems. The best example in plants is the winter memory by which plants can flower in favorable conditions in spring. For this winter memory, epigenetic regulation of FLOWERING LOCUS C (FLC), which acts as a floral repressor, plays a key role. Exposure to prolonged periods of cold results in the gradual suppression of FLC, which allows plants to measure the length of cold and to flower only after a sufficiently long winter. Although many genes involved in histone modifications have been isolated, molecular mechanisms of winter memory are not well understood. Here, we develop a model for chromatin modification, in which the dynamics of a single nucleosome are aggregated to on/off behavior of FLC expression at the cellular level and further integrated to a change of FLC expression at the whole-plant level. We propose cell-population coding of winter memory: each cell is described as a bistable system that shows heterogeneous timing of the transition from on to off in FLC expression under cold and measures the length of cold as the proportion of cells in the off state. This mechanism well explains robust FLC regulation and stable inheritance of winter memory after cell division in response to noisy signals. Winter memory lasts longer if deposition of the repressive histone mark occurs faster. A difference in deposition speed would discriminate between stable maintenance of FLC repression in annuals and transient expression in perennials. Copyright © 2012 Elsevier Ltd. All rights reserved.

  5. Population consequences of winter habitat loss in a migratory shorebird. I. Estimating model parameters

    NARCIS (Netherlands)

    GOSSCUSTARD, JD; CLARKE, RT; BRIGGS, KB; Ens, B.J.; EXO, KM; SMIT, C; BEINTEMA, AJ; CALDOW, RWG; CATT, DC; CLARK, NA; DURELL, SEALD; HARRIS, MP; HULSCHER, JB; MEININGER, PL; PICOZZI, N; PRYSJONES, R; SAFRIEL, UN; WEST, AD

    1. In order to construct a model to predict the effect of winter habitat loss on the migratory population of the European subspecies of the oystercatcher, Haematopus ostralegus ostralegus, data on the reproductive and mortality rates collected throughout Europe over the last 60 years are reviewed.

  6. On the discrepancy between observed and CMIP5 multi-model simulated Barents Sea winter sea ice decline

    OpenAIRE

    Li, Dawei; Zhang, Rong; Knutson, Thomas R.

    2017-01-01

    This study aims to understand the relative roles of external forcing versus internal climate variability in causing the observed Barents Sea winter sea ice extent (SIE) decline since 1979. We identify major discrepancies in the spatial patterns of winter Northern Hemisphere sea ice concentration trends over the satellite period between observations and CMIP5 multi-model mean externally forced response. The CMIP5 externally forced decline in Barents Sea winter SIE is much weaker than that obse...

  7. A toy model for monthly river flow forecasting

    Science.gov (United States)

    Zeng, Xubin; Kiviat, Kira L.; Sakaguchi, Koichi; Mahmoud, Alaa M. A.

    2012-07-01

    SummaryRiver flow forecasting depends on land-atmosphere coupled processes, and is relevant to hydrological applications and land-ocean coupling. A toy model is developed here for monthly river flow forecasting using the river flow and river basin averaged precipitation in prior month. Model coefficients are calibrated for each month using historical data. The toy model is based on water balance, easy to use and reproduce, and robust to calibrate with a short period of data. For five major rivers in the world, its results agree with observations very well. Its prediction uncertainty can be quantified using the model's error statistics or using a dynamic approach, but not by the dispersion of 10,000 ensemble members with different sets of coefficients in the model. Its results are much better than those from a physically based land model even after the mean bias correction. The toy model and a standard neural network available from the MATLAB give similar results, but the latter is more sensitive to the length of calibration period. For the monthly prediction of river flow with a strong seasonal cycle, a modified Nash-Sutcliffe coefficient of efficiency is introduced and is found to be more reliable in model evaluations than the original coefficient of efficiency or the correlation coefficient.

  8. Statistical procedures for evaluating daily and monthly hydrologic model predictions

    Science.gov (United States)

    Coffey, M.E.; Workman, S.R.; Taraba, J.L.; Fogle, A.W.

    2004-01-01

    The overall study objective was to evaluate the applicability of different qualitative and quantitative methods for comparing daily and monthly SWAT computer model hydrologic streamflow predictions to observed data, and to recommend statistical methods for use in future model evaluations. Statistical methods were tested using daily streamflows and monthly equivalent runoff depths. The statistical techniques included linear regression, Nash-Sutcliffe efficiency, nonparametric tests, t-test, objective functions, autocorrelation, and cross-correlation. None of the methods specifically applied to the non-normal distribution and dependence between data points for the daily predicted and observed data. Of the tested methods, median objective functions, sign test, autocorrelation, and cross-correlation were most applicable for the daily data. The robust coefficient of determination (CD*) and robust modeling efficiency (EF*) objective functions were the preferred methods for daily model results due to the ease of comparing these values with a fixed ideal reference value of one. Predicted and observed monthly totals were more normally distributed, and there was less dependence between individual monthly totals than was observed for the corresponding predicted and observed daily values. More statistical methods were available for comparing SWAT model-predicted and observed monthly totals. The 1995 monthly SWAT model predictions and observed data had a regression Rr2 of 0.70, a Nash-Sutcliffe efficiency of 0.41, and the t-test failed to reject the equal data means hypothesis. The Nash-Sutcliffe coefficient and the R r2 coefficient were the preferred methods for monthly results due to the ability to compare these coefficients to a set ideal value of one.

  9. Modeling influences on winter distribution of caribou in northwestern Alaska through use of satellite telemetry

    Directory of Open Access Journals (Sweden)

    Kyle Joly

    2011-09-01

    Full Text Available I hypothesize that the distribution of barren-ground caribou (Rangifer tarandus granti is affected by multiple, interrelated factors. These factors include, but are not limited to, terrain and snow characteristics as well as predation pressure and habitat. To test this hypothesis, I attributed caribou locations derived from satellite telemetry over a 6 year period with terrain (elevation, slope, aspect, and ruggedness, habitat characteristics, and moose density - potentially an index of wolf predation pressure. These locations were compared to random locations, attributed using the same data layers, using logistic regression techniques to develop resource selection functions (RSFs. I found that caribou moved significantly less during mid-winter than early- or late-winter and that cows moved significantly more in April than bulls due to their earlier departure on their spring migration. Distribution was different between cows and bulls. Terrain variables were important factors but were scale-dependent. Cows avoided forested areas, highlighting the importance of tundra habitats, and selected for dwarf shrub, with relatively high lichen cover, and sedge habitat types. Bulls selected for dryas, coniferous forest and dwarf shrub habitats but against lowland sedge, upland shrub and burned tundra. Cow distribution was negatively correlated with moose density at the scale of the Seward Peninsula. My results support the hypothesis that caribou distribution during winter in northwest Alaska is affected by multiple, interrelated factors. These results may be useful for researchers to track and/or model changes in future patterns of range use over winter.

  10. Uncertainty in a monthly water balance model using the generalized ...

    Indian Academy of Sciences (India)

    Uncertainty in a monthly water balance model using the generalized likelihood uncertainty estimation methodology. Diego Rivera1,∗. , Yessica Rivas. 2 and Alex Godoy. 3. 1. Laboratory of Comparative Policy in Water Resources Management, University of Concepcion,. CONICYT/FONDAP 15130015, Concepcion, Chile. 2.

  11. Modeling summer month hydrological drought probabilities in the United States using antecedent flow conditions

    Science.gov (United States)

    Austin, Samuel H.; Nelms, David L.

    2017-01-01

    Climate change raises concern that risks of hydrological drought may be increasing. We estimate hydrological drought probabilities for rivers and streams in the United States (U.S.) using maximum likelihood logistic regression (MLLR). Streamflow data from winter months are used to estimate the chance of hydrological drought during summer months. Daily streamflow data collected from 9,144 stream gages from January 1, 1884 through January 9, 2014 provide hydrological drought streamflow probabilities for July, August, and September as functions of streamflows during October, November, December, January, and February, estimating outcomes 5-11 months ahead of their occurrence. Few drought prediction methods exploit temporal links among streamflows. We find MLLR modeling of drought streamflow probabilities exploits the explanatory power of temporally linked water flows. MLLR models with strong correct classification rates were produced for streams throughout the U.S. One ad hoc test of correct prediction rates of September 2013 hydrological droughts exceeded 90% correct classification. Some of the best-performing models coincide with areas of high concern including the West, the Midwest, Texas, the Southeast, and the Mid-Atlantic. Using hydrological drought MLLR probability estimates in a water management context can inform understanding of drought streamflow conditions, provide warning of future drought conditions, and aid water management decision making.

  12. A complex autoregressive model and application to monthly temperature forecasts

    Directory of Open Access Journals (Sweden)

    X. Gu

    2005-11-01

    Full Text Available A complex autoregressive model was established based on the mathematic derivation of the least squares for the complex number domain which is referred to as the complex least squares. The model is different from the conventional way that the real number and the imaginary number are separately calculated. An application of this new model shows a better forecast than forecasts from other conventional statistical models, in predicting monthly temperature anomalies in July at 160 meteorological stations in mainland China. The conventional statistical models include an autoregressive model, where the real number and the imaginary number are separately disposed, an autoregressive model in the real number domain, and a persistence-forecast model.

  13. Modeling winter ozone episodes near oil and natural gas fields in Wyoming

    Science.gov (United States)

    Wu, Yuling; Rappenglück, Bernhard; Pour-Biazar, Arastoo; Field, Robert A.; Soltis, Jeff

    2017-04-01

    Wintertime ozone episodes have been reported in the oil and natural gas (O&NG) producing fields in Uintah Basin, Utah and the Upper Green River Basin (UGRB) in Wyoming in recent years. High concentrations of ozone precursors facilitated by favorable meteorological conditions, including low wind and shallow boundary layer (BL), were found in these episodes, although the exact roles of these precursor species in different O&NG fields are to be determined. Meanwhile, snow cover is also found to play an important role in these winter ozone episodes as the cold snow covered surface enhances the inversion, further limits the BL and the high snow albedo greatly boosts photolysis reactions that are closely related to ozone chemistry. In this study, we utilize model simulation to explore the role of chemical compositions, in terms of different VOC groups and NOx, and that of the enhanced photolysis due to snow cover in the UGRB ozone episodes in the late winter of 2011.

  14. Application of regional climate models to the Indian winter monsoon over the western Himalayas.

    Science.gov (United States)

    Dimri, A P; Yasunari, T; Wiltshire, A; Kumar, P; Mathison, C; Ridley, J; Jacob, D

    2013-12-01

    The Himalayan region is characterized by pronounced topographic heterogeneity and land use variability from west to east, with a large variation in regional climate patterns. Over the western part of the region, almost one-third of the annual precipitation is received in winter during cyclonic storms embedded in westerlies, known locally as the western disturbance. In the present paper, the regional winter climate over the western Himalayas is analyzed from simulations produced by two regional climate models (RCMs) forced with large-scale fields from ERA-Interim. The analysis was conducted by the composition of contrasting (wet and dry) winter precipitation years. The findings showed that RCMs could simulate the regional climate of the western Himalayas and represent the atmospheric circulation during extreme precipitation years in accordance with observations. The results suggest the important role of topography in moisture fluxes, transport and vertical flows. Dynamical downscaling with RCMs represented regional climates at the mountain or even event scale. However, uncertainties of precipitation scale and liquid-solid precipitation ratios within RCMs are still large for the purposes of hydrological and glaciological studies. Copyright © 2013 Elsevier B.V. All rights reserved.

  15. Modelling soil water content variations under drought stress on soil column cropped with winter wheat

    Directory of Open Access Journals (Sweden)

    Csorba Szilveszter

    2014-12-01

    Full Text Available Mathematical models are effective tools for evaluating the impact of predicted climate change on agricultural production, but it is difficult to test their applicability to future weather conditions. We applied the SWAP model to assess its applicability to climate conditions, differing from those, for which the model was developed. We used a database obtained from a winter wheat drought stress experiment. Winter wheat was grown in six soil columns, three having optimal water supply (NS, while three were kept under drought-stressed conditions (S. The SWAP model was successfully calibrated against measured values of potential evapotranspiration (PET, potential evaporation (PE and total amount of water (TSW in the soil columns. The Nash-Sutcliffe model efficiency coefficient (N-S for TWS for the stressed columns was 0.92. For the NS treatment, we applied temporally variable soil hydraulic properties because of soil consolidation caused by regular irrigation. This approach improved the N-S values for the wetting-drying cycle from -1.77 to 0.54. We concluded that the model could be used for assessing the effects of climate change on soil water regime. Our results indicate that soil water balance studies should put more focus on the time variability of structuredependent soil properties.

  16. Wintering habitat model for the North Atlantic Right Whale (Eubalaena glacialis) in the southeastern United States.

    Science.gov (United States)

    Gowan, Timothy A; Ortega-Ortiz, Joel G

    2014-01-01

    The coastal waters off the southeastern United States (SEUS) are a primary wintering ground for the endangered North Atlantic right whale (Eubalaena glacialis), used by calving females along with other adult and juvenile whales. Management actions implemented in this area for the recovery of the right whale population rely on accurate habitat characterization and the ability to predict whale distribution over time. We developed a temporally dynamic habitat model to predict wintering right whale distribution in the SEUS using a generalized additive model framework and aerial survey data from 2003/2004 through 2012/2013. We built upon previous habitat models for right whales in the SEUS and include data from new aerial surveys that extend the spatial coverage of the analysis, particularly in the northern portion of this wintering ground. We summarized whale sightings, survey effort corrected for probability of whale detection, and environmental data at a semimonthly resolution. Consistent with previous studies, sea surface temperature (SST), water depth, and survey year were significant predictors of right whale relative abundance. Additionally, distance to shore, distance to the 22°C SST isotherm, and an interaction between time of year and latitude (to account for the latitudinal migration of whales) were also selected in the analysis presented here. Predictions from the model revealed that the location of preferred habitat differs within and between years in correspondence with variation in environmental conditions. Although cow-calf pairs were rarely sighted in the company of other whales, there was minimal evidence that the preferred habitat of cow-calf pairs was different than that of whale groups without calves at the scale of this study. The results of this updated habitat model can be used to inform management decisions for a migratory species in a dynamic oceanic environment.

  17. Sensitivity of soil permafrost to winter warming: Modeled impacts of climate change.

    Science.gov (United States)

    Bouskill, N.; Riley, W. J.; Mekonnen, Z. A.; Grant, R.

    2016-12-01

    High-latitude tundra soils are warming at nearly twice the rate of temperate ecosystems. Changes in temperature and soil moisture can feedback on the processes controlling the carbon balance of tundra soils by altering plant community composition and productivity and microbial decomposition rates. Recent field manipulation experiments have shown that elevated soil and air temperatures can stimulate both gross primary productivity and ecosystem respiration. However, the observed soil carbon gains following summer time stimulation of plant productivity have been more than offset by elevated decomposition rates during the rest of the year, and particularly over winter. A critical uncertainty is whether these short-term responses also represent the long-term trajectory of tundra ecosystems under chronic disturbance. Herein we employ a mechanistic land-model (ecosys) that represents many of the key above- and belowground processes regulating the carbon balance of tundra soils to simulate a winter warming experiment at Eight Mile Lake, Alaska. Using this model we examined the short-term (5 - 10 year) influence of soil warming through the wintertime by mimicking the accumulation of a deeper snow pack. This deeper snow pack was removed to a height equal to that of the snow pack over control plots prior to snow melt. We benchmarked the model using physical and biological measurements made over the course of a six-year experiment at the site. The model accurately represented the effect of the experimental manipulation on thaw depth, N mineralization, winter respiration, and ecosystem gross and net primary production. After establishing confidence in the modeled short-term responses, we extend the same chronic disturbance to 2050 to examine the long-term response of the plant and microbial communities to warming. We discuss our results in reference to the long-term trajectory of the carbon and nutrient cycles of high-latitude permafrost regions.

  18. Modelling raster-based monthly water balance components for Europe

    Energy Technology Data Exchange (ETDEWEB)

    Ulmen, C.

    2000-11-01

    The terrestrial runoff component is a comparatively small but sensitive and thus significant quantity in the global energy and water cycle at the interface between landmass and atmosphere. As opposed to soil moisture and evapotranspiration which critically determine water vapour fluxes and thus water and energy transport, it can be measured as an integrated quantity over a large area, i.e. the river basin. This peculiarity makes terrestrial runoff ideally suited for the calibration, verification and validation of general circulation models (GCMs). Gauging stations are not homogeneously distributed in space. Moreover, time series are not necessarily continuously measured nor do they in general have overlapping time periods. To overcome this problems with regard to regular grid spacing used in GCMs, different methods can be applied to transform irregular data to regular so called gridded runoff fields. The present work aims to directly compute the gridded components of the monthly water balance (including gridded runoff fields) for Europe by application of the well-established raster-based macro-scale water balance model WABIMON used at the Federal Institute of Hydrology, Germany. Model calibration and validation is performed by separated examination of 29 representative European catchments. Results indicate a general applicability of the model delivering reliable overall patterns and integrated quantities on a monthly basis. For time steps less then too weeks further research and structural improvements of the model are suggested. (orig.)

  19. Reduced-fat Gouda-type cheese enriched with vitamin D3effectively prevents vitamin D deficiency during winter months in postmenopausal women in Greece.

    Science.gov (United States)

    Manios, Yannis; Moschonis, George; Mavrogianni, Christina; van den Heuvel, Eghm; Singh-Povel, Cécile M; Kiely, Mairead; Cashman, Kevin D

    2017-10-01

    The primary aim of the present study was to examine the effectiveness of daily consumption of vitamin D 3 -enriched, reduced-fat Gouda-type cheese on 25-hydroxyvitamin D (25(OH)D) concentration in postmenopausal women. Health-related quality of life (HRQL) indices were examined as secondary outcomes. This is a single-blinded (i.e., to study participants), randomized, controlled food-based dietary intervention study. A sample of 79 postmenopausal women (55-75 years old) was randomized either to a control group (CG: n = 39) or an intervention group (IG: n = 40) that consumed, as part of their usual diet, 60 g of either non-enriched or vitamin D 3 enriched Gouda-type cheese, respectively, for eight consecutive weeks (i.e., from January to March 2015). Sixty grams of enriched cheese provided a daily dose of 5.7 μg of vitamin D 3 . There was a differential response of mean (95 % CI) serum 25(OH)D levels in the IG and CG, with the former increasing and the latter decreasing significantly over the eight weeks of the trial [i.e., by 5.1 (3.4, 6.9) nmol/L vs. -4.6 (-6.4, -2.8) nmol/L, P D levels  0.1). Consumption of 60 g of vitamin D 3 -enriched, reduced-fat Gouda-type cheese provided a daily dose of 5.7 μg of additional vitamin D 3 and was effective in increasing mean serum 25(OH)D concentration and in counteracting vitamin D deficiency during winter months in postmenopausal women in Greece.

  20. Influence of CMV/EBV serostatus on respiratory infection incidence during 4 months of winter training in a student cohort of endurance athletes.

    Science.gov (United States)

    He, Cheng-Shiun; Handzlik, Michal; Muhamad, Ayu; Gleeson, Michael

    2013-10-01

    The purpose of this study was to examine the influence of previous infection with cytomegalovirus (CMV) or Epstein Barr virus (EBV) on the incidence, severity and duration of upper respiratory tract infections (URTIs) in endurance athletes during a 4-month winter training period. Blood samples were obtained from 236 subjects (166 males and 70 females, aged 18-35 years) at the start of the study period. Plasma samples were analysed for CMV and EBV serostatus. Weekly training and daily illness logs were kept for the next 16 weeks. With regard to CMV/EBV serostatus, the results indicated that athletes with previous CMV infection (n = 58, 25 % of cohort) had significantly fewer URTI symptom days (median 2 vs. 4 days, p = 0.033) during the study period than those with no previous infection (n = 178, 75 %), whereas positive EBV serostatus (n = 197, 84 %) had no influence on URTI episode incidence, severity or duration. Moreover, we found that athletes with prior infection of both CMV and EBV (n = 50, 21 %) had 50 % fewer URTI episodes (p = 0.04) and symptom days (median 2 vs 8 days, p = 0.01) than athletes who were seronegative for both CMV and EBV (n = 31, 13 %). Previous coinfection with CMV and EBV might promote protective immune surveillance to lower the risk of URTI. Further research is required to clarify why previous CMV and EBV infection reduces the incidence of URTI.

  1. Uncertainties in modelling heterogeneous chemistry and Arctic ozone depletion in the winter 2009/2010

    Directory of Open Access Journals (Sweden)

    I. Wohltmann

    2013-04-01

    Full Text Available Stratospheric chemistry and denitrification are simulated for the Arctic winter 2009/2010 with the Lagrangian Chemistry and Transport Model ATLAS. A number of sensitivity runs is used to explore the impact of uncertainties in chlorine activation and denitrification on the model results. In particular, the efficiency of chlorine activation on different types of liquid aerosol versus activation on nitric acid trihydrate clouds is examined. Additionally, the impact of changes in reaction rate coefficients, in the particle number density of polar stratospheric clouds, in supersaturation, temperature or the extent of denitrification is investigated. Results are compared to satellite measurements of MLS and ACE-FTS and to in-situ measurements onboard the Geophysica aircraft during the RECONCILE measurement campaign. It is shown that even large changes in the underlying assumptions have only a small impact on the modelled ozone loss, even though they can cause considerable differences in chemical evolution of other species and in denitrification. Differences in column ozone between the sensitivity runs stay below 10% at the end of the winter. Chlorine activation on liquid aerosols alone is able to explain the observed magnitude and morphology of the mixing ratios of active chlorine, reservoir gases and ozone. This is even true for binary aerosols (no uptake of HNO3 from the gas-phase allowed in the model. Differences in chlorine activation between sensitivity runs are within 30%. Current estimates of nitric acid trihydrate (NAT number density and supersaturation imply that, at least for this winter, NAT clouds play a relatively small role compared to liquid clouds in chlorine activation. The change between different reaction rate coefficients for liquid or solid clouds has only a minor impact on ozone loss and chlorine activation in our sensitivity runs.

  2. Modelling and forecasting monthly swordfish catches in the Eastern Mediterranean

    Directory of Open Access Journals (Sweden)

    Konstantinos I. Stergiou

    2003-04-01

    Full Text Available In this study, we used the X-11 census technique for modelling and forecasting the monthly swordfish (Xiphias gladius catches in the Greek Seas during 1982-1996 and 1997 respectively, using catches reported by the National Statistical Service of Greece (NSSG. Forecasts built with X-11 were also compared with those derived from ARIMA andWinter’s exponential smoothing (WES models. The X-11 method captured the features of the study series and outperformed the other two methods, in terms of both fitting and forecasting performance, for all the accuracy measures used. Thus, with the exception of October, November and December 1997, when the corresponding absolute percentage error(APE values were very high (as high as 178.6% because of the low level of the catches, monthly catches during the remaining months of 1997 were predicted accurately, with a mean APE of 12.5%. In contrast, the mean APE values of the other two methods for the same months were higher (ARIMA: 14.6%; WES: 16.6%. The overall good performance of X-11 andthe fact that it provides an insight into the various components (i.e. the seasonal, trend-cycle and irregular components of the time series of interest justify its use in fisheries research. The basic features of the swordfish catches revealed by the application of the X-11 method, the effect of the length of the forecasting horizon on forecasting accuracy and the accuracy of the catches reported by NSSG are also discussed.

  3. Modeling Root Growth, Crop Growth and N Uptake of Winter Wheat Based on SWMS_2D: Model and Validation

    Directory of Open Access Journals (Sweden)

    Dejun Yang

    Full Text Available ABSTRACT Simulations for root growth, crop growth, and N uptake in agro-hydrological models are of significant concern to researchers. SWMS_2D is one of the most widely used physical hydrologically related models. This model solves equations that govern soil-water movement by the finite element method, and has a public access source code. Incorporating key agricultural components into the SWMS_2D model is of practical importance, especially for modeling some critical cereal crops such as winter wheat. We added root growth, crop growth, and N uptake modules into SWMS_2D. The root growth model had two sub-models, one for root penetration and the other for root length distribution. The crop growth model used was adapted from EU-ROTATE_N, linked to the N uptake model. Soil-water limitation, nitrogen limitation, and temperature effects were all considered in dry-weight modeling. Field experiments for winter wheat in Bouwing, the Netherlands, in 1983-1984 were selected for validation. Good agreements were achieved between simulations and measurements, including soil water content at different depths, normalized root length distribution, dry weight and nitrogen uptake. This indicated that the proposed new modules used in the SWMS_2D model are robust and reliable. In the future, more rigorous validation should be carried out, ideally under 2D situations, and attention should be paid to improve some modules, including the module simulating soil N mineralization.

  4. Forecasting of primary energy consumption data in the United States: A comparison between ARIMA and Holter-Winters models

    Science.gov (United States)

    Rahman, A.; Ahmar, A. S.

    2017-09-01

    This research has a purpose to compare ARIMA Model and Holt-Winters Model based on MAE, RSS, MSE, and RMS criteria in predicting Primary Energy Consumption Total data in the US. The data from this research ranges from January 1973 to December 2016. This data will be processed by using R Software. Based on the results of data analysis that has been done, it is found that the model of Holt-Winters Additive type (MSE: 258350.1) is the most appropriate model in predicting Primary Energy Consumption Total data in the US. This model is more appropriate when compared with Holt-Winters Multiplicative type (MSE: 262260,4) and ARIMA Seasonal model (MSE: 723502,2).

  5. The arctic winter stratosphere: simulated with a 3-D chemistry transport model

    NARCIS (Netherlands)

    Broek, Martina Maria Petronella van den

    2004-01-01

    During the past two decades, the ozone layer has developed a “hole” each winter and spring above the Antarctic continent. Also in cold Arctic winters substantial stratospheric ozone depletion has been measured, although less than in the Antarctic stratosphere. In the Arctic winter stratosphere,

  6. Modeling human health risks of airborne endotoxin in homes during the winter and summer seasons

    Energy Technology Data Exchange (ETDEWEB)

    Liao, Vivian Hsiu-Chuan, E-mail: vivianliao@ntu.edu.tw [Department of Bioenvironmental Systems Engineering, National Taiwan University, Taipei 106, Taiwan (China); Chio, Chia-Pin; Chou, Wei-Chun; Ju, Yun-Ru; Liao, Chung-Min [Department of Bioenvironmental Systems Engineering, National Taiwan University, Taipei 106, Taiwan (China)

    2010-03-01

    Endotoxin, a component of gram-negative bacterial cell walls, is a pro-inflammatory agent that induces local and systemic inflammatory responses in normal subjects which can contribute to the risk of developing asthma and chronic obstructive lung diseases. A probabilistic approach linking models of exposure, internal dosimetry, and health effects was carried out to quantitatively assess the potential inhalation risk of airborne endotoxin in homes during the winter and summer seasons. Combining empirical data and modeling results, we show that the half-maximum effect of the endotoxin dose (ED50) was estimated to be 707.9 (95% confidence interval (CI): 308.8-1287.0) endotoxin units (EU) for body temperature change, 481.8 (95% CI: 333.2-630.3) EU for elevation of neutrophils, and 1174.5 (95% CI: 816.0-1532.9) EU for elevation of the cytokine, interleukin-6. Our study also suggests that airborne endotoxin in homes may pose potential risks, and a higher risk for elevation of neutrophils and cytokine interleukin-6 appeared in winter season than in summer. Our study offers a risk-management framework for discussion of future studies of human respiratory exposure to airborne endotoxin.

  7. Winter wheat water productivity evaluated by the developed remote sensing evapotranspiration model in Hebei Plain, China.

    Science.gov (United States)

    Zhang, Shengwei; Zhao, Hongbin; Lei, Huimin; Shao, Hongbo; Liu, Tingxi

    2015-01-01

    Agricultural water is the main reason for the rapid decline of the NCP groundwater levels. It is of vital importance for the NCP sustainable agricultural development to master the ETa and its CWP. In this paper, the EBEM model was developed according to the theory of energy balance. From 2001 to 2006, the winter wheat ETa and CWP were estimated, and the spatial and temporal variations and their influencing factors were studied in the Hebei Plain. The results indicate that the EBEM model performed well by applying MODIS data to estimate the daily net radiation and ETa. For the daytime net radiation, the relative error between the estimation and the measurement amounted to 8.2% and the SEE was 0.82 MJ m(-2)/day. The average ETa deviation between the estimates and the measures amounted to 0.86 mm daily, and the SE was 1.2 mm. The spatial variations indicated that the major distribution of ETa ranged from 350 to 450 mm, which trended downward within the study area from west to east. In the study period, the winter wheat CWP was mainly distributed between 0.29 and 1.67 kg/m(3). In space, the CWP was higher in the west than in the east.

  8. Monthly to seasonal low flow prediction: statistical versus dynamical models

    Science.gov (United States)

    Ionita-Scholz, Monica; Klein, Bastian; Meissner, Dennis; Rademacher, Silke

    2016-04-01

    While the societal and economical impacts of floods are well documented and assessable, the impacts of lows flows are less studied and sometimes overlooked. For example, over the western part of Europe, due to intense inland waterway transportation, the economical loses due to low flows are often similar compared to the ones due to floods. In general, the low flow aspect has the tendency to be underestimated by the scientific community. One of the best examples in this respect is the facts that at European level most of the countries have an (early) flood alert system, but in many cases no real information regarding the development, evolution and impacts of droughts. Low flows, occurring during dry periods, may result in several types of problems to society and economy: e.g. lack of water for drinking, irrigation, industrial use and power production, deterioration of water quality, inland waterway transport, agriculture, tourism, issuing and renewing waste disposal permits, and for assessing the impact of prolonged drought on aquatic ecosystems. As such, the ever-increasing demand on water resources calls for better a management, understanding and prediction of the water deficit situation and for more reliable and extended studies regarding the evolution of the low flow situations. In order to find an optimized monthly to seasonal forecast procedure for the German waterways, the Federal Institute of Hydrology (BfG) is exploring multiple approaches at the moment. On the one hand, based on the operational short- to medium-range forecasting chain, existing hydrological models are forced with two different hydro-meteorological inputs: (i) resampled historical meteorology generated by the Ensemble Streamflow Prediction approach and (ii) ensemble (re-) forecasts of ECMWF's global coupled ocean-atmosphere general circulation model, which have to be downscaled and bias corrected before feeding the hydrological models. As a second approach BfG evaluates in cooperation with

  9. Empirical models of monthly and annual surface albedo in managed boreal forests of Norway

    Science.gov (United States)

    Bright, Ryan M.; Astrup, Rasmus; Strømman, Anders H.

    2013-04-01

    As forest management activities play an increasingly important role in climate change mitigation strategies of Nordic regions such as Norway, Sweden, and Finland -- the need for a more comprehensive understanding of the types and magnitude of biogeophysical climate effects and their various tradeoffs with the global carbon cycle becomes essential to avoid implementation of sub-optimal policy. Forest harvest in these regions reduces the albedo "masking effect" and impacts Earth's radiation budget in opposing ways to that of concomitant carbon cycle perturbations; thus, policies based solely on biogeochemical considerations in these regions risk being counterproductive. There is therefore a need to better understand how human disturbances (i.e., forest management activities) affect important biophysical factors like surface albedo. An 11-year remotely sensed surface albedo dataset coupled with stand-level forest management data for a variety of stands in Norway's most productive logging region are used to develop regression models describing temporal changes in monthly and annual forest albedo following clear-cut harvest disturbance events. Datasets are grouped by dominant tree species and site indices (productivity), and two alternate multiple regression models are developed and tested following a potential plus modifier approach. This resulted in an annual albedo model with statistically significant parameters that explains a large proportion of the observed variation, requiring as few as two predictor variables: i) average stand age - a canopy modifier predictor of albedo, and ii) stand elevation - a local climate predictor of a forest's potential albedo. The same model structure is used to derive monthly albedo models, with models for winter months generally found superior to summer models, and conifer models generally outperforming deciduous. We demonstrate how these statistical models can be applied to routine forest inventory data to predict the albedo

  10. Diagnosis and Modeling of the Explosive Development of Winter Storms: Sensitivity to PBL Schemes

    Science.gov (United States)

    Liberato, Margarida L. R.; Pradhan, Prabodha K.

    2014-05-01

    The correct representation of extreme windstorms in regional models is of great importance for impact studies of climate change. The Iberian Peninsula has recently witnessed major damage from winter extratropical intense cyclones like Klaus (January 2009), Xynthia (February 2010) and Gong (January 2013) which formed over the mid-Atlantic, experienced explosive intensification while travelling eastwards at lower latitudes than usual [Liberato et al. 2011; 2013]. In this paper the explosive development of these storms is simulated by the advanced mesoscale Weather Research and Forecasting Model (WRF v 3.4.1), initialized with NCEP Final Analysis (FNL) data as initial and lateral boundary conditions (boundary conditions updated in every 3 hours intervals). The simulation experiments are conducted with two domains, a coarser (25km) and nested (8.333km), covering the entire North Atlantic and Iberian Peninsula region. The characteristics of these storms (e.g. wind speed, precipitation) are studied from WRF model and compared with multiple observations. In this context simulations with different Planetary Boundary Layer (PBL) schemes are performed. This approach aims at understanding which mechanisms favor the explosive intensification of these storms at a lower than usual latitudes, thus improving the knowledge of atmospheric dynamics (including small-scale processes) on controlling the life cycle of midlatitude extreme storms and contributing to the improvement in predictability and in our ability to forecast storms' impacts over Iberian Peninsula. Acknowledgments: This work was partially supported by FEDER (Fundo Europeu de Desenvolvimento Regional) funds through the COMPETE (Programa Operacional Factores de Competitividade) and by national funds through FCT (Fundação para a Ciência e a Tecnologia, Portugal) under project STORMEx FCOMP-01-0124-FEDER- 019524 (PTDC/AAC-CLI/121339/2010). References: Liberato M.L.R., J.G. Pinto, I.F. Trigo, R.M. Trigo (2011) Klaus - an

  11. Development of groundwater pesticide exposure modeling scenarios for vulnerable spring and winter wheat-growing areas.

    Science.gov (United States)

    Padilla, Lauren; Winchell, Michael; Peranginangin, Natalia; Grant, Shanique

    2017-11-01

    Wheat crops and the major wheat-growing regions of the United States are not included in the 6 crop- and region-specific scenarios developed by the US Environmental Protection Agency (USEPA) for exposure modeling with the Pesticide Root Zone Model conceptualized for groundwater (PRZM-GW). The present work augments the current scenarios by defining appropriately vulnerable PRZM-GW scenarios for high-producing spring and winter wheat-growing regions that are appropriate for use in refined pesticide exposure assessments. Initial screening-level modeling was conducted for all wheat areas across the conterminous United States as defined by multiple years of the Cropland Data Layer land-use data set. Soil, weather, groundwater temperature, evaporation depth, and crop growth and management practices were characterized for each wheat area from publicly and nationally available data sets and converted to input parameters for PRZM. Approximately 150 000 unique combinations of weather, soil, and input parameters were simulated with PRZM for an herbicide applied for postemergence weed control in wheat. The resulting postbreakthrough average herbicide concentrations in a theoretical shallow aquifer were ranked to identify states with the largest regions of relatively vulnerable wheat areas. For these states, input parameters resulting in near 90th percentile postbreakthrough average concentrations corresponding to significant wheat areas with shallow depth to groundwater formed the basis for 4 new spring wheat scenarios and 4 new winter wheat scenarios to be used in PRZM-GW simulations. Spring wheat scenarios were identified in North Dakota, Montana, Washington, and Texas. Winter wheat scenarios were identified in Oklahoma, Texas, Kansas, and Colorado. Compared to the USEPA's original 6 scenarios, postbreakthrough average herbicide concentrations in the new scenarios were lower than all but Florida Potato and Georgia Coastal Peanuts of the original scenarios and better

  12. Effect of dust models on global nuclear winter. Master's thesis

    Energy Technology Data Exchange (ETDEWEB)

    Pontier, P.Q.

    1986-03-01

    A series of optical-depth calculations were accomplished to assess the effects of various existing dust and soot models on the transmission of incident sunlight. A change in the standard deviation of the particle-size distribution from two to four, assuming constant total density, resulted in a decrease in the visible optical depth by a factor of ten. A technique using a method of direct integration was developed for the calculation of the effective optical depth of nuclear-induced dust and soot clouds. Contributions from directly transmitted photons, first scattered photons using anisotropic cross sections, and all subsequently scattered photons were used to calculate the amount of light transmitted through the cloud. Absorption effects were also included. The results of this study were comparable to the results of several recent nuclear winter studies.

  13. A Winter Distribution Model for Bicknell’s Thrush (Catharus bicknelli), a Conservation Tool for a Threatened Migratory Songbird

    Science.gov (United States)

    McFarland, Kent P.; Rimmer, Christopher C.; Goetz, James E.; Aubry, Yves; Wunderle, Joseph M.; Sutton, Anne; Townsend, Jason M.; Sosa, Alejandro Llanes; Kirkconnell, Arturo

    2013-01-01

    Conservation planning and implementation require identifying pertinent habitats and locations where protection and management may improve viability of targeted species. The winter range of Bicknell’s Thrush (Catharus bicknelli), a threatened Nearctic-Neotropical migratory songbird, is restricted to the Greater Antilles. We analyzed winter records from the mid-1970s to 2009 to quantitatively evaluate winter distribution and habitat selection. Additionally, we conducted targeted surveys in Jamaica (n = 433), Cuba (n = 363), Dominican Republic (n = 1,000), Haiti (n = 131) and Puerto Rico (n = 242) yielding 179 sites with thrush presence. We modeled Bicknell’s Thrush winter habitat selection and distribution in the Greater Antilles in Maxent version 3.3.1. using environmental predictors represented in 30 arc second study area rasters. These included nine landform, land cover and climatic variables that were thought a priori to have potentially high predictive power. We used the average training gain from ten model runs to select the best subset of predictors. Total winter precipitation, aspect and land cover, particularly broadleaf forests, emerged as important variables. A five-variable model that contained land cover, winter precipitation, aspect, slope, and elevation was the most parsimonious and not significantly different than the models with more variables. We used the best fitting model to depict potential winter habitat. Using the 10 percentile threshold (>0.25), we estimated winter habitat to cover 33,170 km2, nearly 10% of the study area. The Dominican Republic contained half of all potential habitat (51%), followed by Cuba (15.1%), Jamaica (13.5%), Haiti (10.6%), and Puerto Rico (9.9%). Nearly one-third of the range was found to be in protected areas. By providing the first detailed predictive map of Bicknell’s Thrush winter distribution, our study provides a useful tool to prioritize and direct conservation planning for this and

  14. Winter MVC

    OpenAIRE

    Castellón Gadea, Pasqual

    2013-01-01

    Winter MVC és un framework de presentació basat en Spring MVC que simplifica la metodologia de configuracions. Winter MVC es un framework de presentación basado en Spring MVC que simplifica la metodología de configuraciones. Winter MVC is a presentation framework that simplifies Spring MVC configuration methodology.

  15. Assessment of atmosphere-ocean general circulation model simulations of winter northern hemisphere atmospheric blocking

    Energy Technology Data Exchange (ETDEWEB)

    Vial, Jessica; Osborn, Tim J. [University of East Anglia, Climatic Research Unit, School of Environmental Sciences, Norwich (United Kingdom)

    2012-07-15

    An assessment of six coupled Atmosphere-Ocean General Circulation Models (AOGCMs) is undertaken in order to evaluate their ability in simulating winter atmospheric blocking highs in the northern hemisphere. The poor representation of atmospheric blocking in climate models is a long-standing problem (e.g. D'Andrea et al. in Clim Dyn 4:385-407, 1998), and despite considerable effort in model development, there is only a moderate improvement in blocking simulation. A modified version of the Tibaldi and Molteni (in Tellus A 42:343-365, 1990) blocking index is applied to daily averaged 500 hPa geopotential fields, from the ERA-40 reanalysis and as simulated by the climate models, during the winter periods from 1957 to 1999. The two preferred regions of blocking development, in the Euro-Atlantic and North Pacific, are relatively well captured by most of the models. However, the prominent error in blocking simulations consists of an underestimation of the total frequency of blocking episodes over both regions. A more detailed analysis revealed that this error was due to an insufficient number of medium spells and long-lasting episodes, and a shift in blocking lifetime distributions towards shorter blocks in the Euro-Atlantic sector. In the Pacific, results are more diverse; the models are equally likely to overestimate or underestimate the frequency at different spell lengths. Blocking spatial signatures are relatively well simulated in the Euro-Atlantic sector, while errors in the intensity and geographical location of the blocks emerge in the Pacific. The impact of models' systematic errors on blocking simulation has also been analysed. The time-mean atmospheric circulation biases affect the frequency of blocking episodes, and the maximum event duration in the Euro-Atlantic region, while they sometimes cause geographical mislocations in the Pacific sector. The analysis of the systematic error in time-variability has revealed a negative relationship between the

  16. Route prediction model of infectious diseases for 2018 Winter Olympics in Korea

    Science.gov (United States)

    Kim, Eungyeong; Lee, Seok; Byun, Young Tae; Kim, Jae Hun; Lee, Hyuk-jae; Lee, Taikjin

    2014-03-01

    There are many types of respiratory infectious diseases caused by germs, virus, mycetes and parasites. Researchers recently have tried to develop mathematical models to predict the epidemic of infectious diseases. However, with the development of ground transportation system in modern society, the spread of infectious diseases became faster and more complicated in terms of the speed and the pathways. The route of infectious diseases during Vancouver Olympics was predicted based on the Susceptible-Infectious-Recovered (SIR) model. In this model only the air traffic as an essential factor for the intercity migration of infectious diseases was involved. Here, we propose a multi-city transmission model to predict the infection route during 2018 Winter Olympics in Korea based on the pre-existing SIR model. Various types of transportation system such as a train, a car, a bus, and an airplane for the interpersonal contact in both inter- and intra-city are considered. Simulation is performed with assumptions and scenarios based on realistic factors including demographic, transportation and diseases data in Korea. Finally, we analyze an economic profit and loss caused by the variation of the number of tourists during the Olympics.

  17. K-Pg extinction patterns in marine and freshwater environments: The impact winter model

    Science.gov (United States)

    Robertson, Douglas S.; Lewis, William M.; Sheehan, Peter M.; Toon, Owen B.

    2013-07-01

    Chicxulub asteroid impact produced massive extinction in terrestrial environments most likely through an intense heat pulse and subsequent widespread fires. Aquatic environments were shielded from this heat and fire but nevertheless showed massive extinction in marine environments and, for reasons unexplained, far less extinction in freshwater environments. Extinction in marine environments resulted from the effects of an "impact winter" caused by dust and smoke in the atmosphere that extinguished sunlight at the Earth's surface for a period of months to years. The resulting cessation of photosynthesis caused a globally extensive extinction of phytoplankton taxa. Because aquatic ecosystems, unlike terrestrial environments, are strongly dependent on daily photosynthetic output by autotrophs, loss of phytoplankton likely caused catastrophic mortality and extinction in aquatic ecosystems. Other potential causes of mortality in aquatic ecosystems include lower ambient temperatures and anoxia due to the lack of photosynthetic oxygen. Inland waters, although probably subject to high mortality, showed lower proportionate extinction than marine environments probably because of the greater potential among the freshwater taxa for dormancy, the greater efficiency of reaeration by rapid flow to offset oxygen demand, abundant thermal refugia fed by groundwater at moderate temperatures, and preadaptation of freshwater taxa to a great degree of environmental variability. In addition, detrital feeders appear to have had low extinction rates in either marine or freshwater environments, but again freshwater taxa would have been favored by higher renewal rates of detrital organic matter as a result of their direct hydrologic contact with soil.

  18. The use of partial thickness method and zero wet bulb temperature for discriminating precipitation type during winter months at the Ebro basin in Spain

    Science.gov (United States)

    Buisan, S.; Revuelto, J.

    2010-09-01

    The forecast office of the State Meteorological Agency of Spain (AEMET) which is located in the city of Zaragoza provides weather forecast, warnings and aviation forecast products for Aragón, Navarra and La Rioja regions. This area of Spain lies mainly on the Ebro river basin. Although the likelihood of snowfall in this territory is low, a forecasting of snow-depth higher than 5cm for low elevations activates the orange warning which must be issued to local emergency management and civil protection authorities. Zero wet bulb temperature has been historically the main tool for forecasting the altitude of snow-rain boundary at the forecast office; it shows the freezing level limit due to evaporational cooling when lower troposphere is saturated from aloft. This work adds two new parameters, the 1000-850 mb and the 850-700 mb thickness in order to characterize the thermal structure of surface based cold air and atmospheric mid-levels. The three main airports in this area Zaragoza-Aragón, Logroño-La Rioja and Pamplona-Navarra are located at altitudes below 500 m. They are thus suitable for this study. In addition, more than 16 years of meteorological observations every hour, known as METAR (Meteorological Aerodrome Report), are available at these locations. These observations were analysed and the predominant precipitation type during a six-hour period was characterized. The 00h, 06h, 12h and 18h analysis time of the ECMWF Forecast model were employed in order to get the parameters at the day and time when the precipitation took place. The most representative grid point of the model for each airport was chosen in order to illustrate the atmospheric conditions. A correlation between precipitation type and zero wet bulb temperature, 1000-850 mb and the 850-700 mb thickness was done for more than 230 different situations during a 16 year period. As a result, we plotted a series of site specific charts for each airport based on these parameters, in order to describe the

  19. Modeling large-scale winter recreation terrain selection with implications for recreation management and wildlife

    Science.gov (United States)

    Lucretia E. Olson; John R. Squires; Elizabeth K. Roberts; Aubrey D. Miller; Jacob S. Ivan; Mark Hebblewhite

    2017-01-01

    Winter recreation is a rapidly growing activity, and advances in technology make it possible for increasing numbers of people to access remote backcountry terrain. Increased winter recreation may lead to more frequent conflict between recreationists, as well as greater potential disturbance to wildlife. To better understand the environmental characteristics favored by...

  20. Short-term Forecast Model of Vehicles Volume Based on ARIMA Seasonal Model and Holt-Winters

    Directory of Open Access Journals (Sweden)

    Wang Zhi-Hui

    2017-01-01

    Full Text Available In order to alleviate the urban traffic congestion and ensure traffic safety, we need to do a good job in urban road traffic safety planning, make the real-time analysis and forecast of urban traffic flow to detect changes of current traffic flow in time, make scientific planning of roads and improve the road service ability and the transport efficiency of freight vehicles. The data of short-term vehicles volume is characterized by uncertainty and timing correlation series. Given this, the ARIMA seasonal model and the Holt-Winters model are used to establish a forecasting model for the short-term vehicles volume of the city. Finally, we compare the model with predictions.

  1. A methodology to urban air quality assessment during large time periods of winter using computational fluid dynamic models

    Science.gov (United States)

    Parra, M. A.; Santiago, J. L.; Martín, F.; Martilli, A.; Santamaría, J. M.

    2010-06-01

    The representativeness of point measurements in urban areas is limited due to the strong heterogeneity of the atmospheric flows in cities. To get information on air quality in the gaps between measurement points, and have a 3D field of pollutant concentration, Computational Fluid Dynamic (CFD) models can be used. However, unsteady simulations during time periods of the order of months, often required for regulatory purposes, are not possible for computational reasons. The main objective of this study is to develop a methodology to evaluate the air quality in a real urban area during large time periods by means of steady CFD simulations. One steady simulation for each inlet wind direction was performed and factors like the number of cars inside each street, the length of streets and the wind speed and direction were taken into account to compute the pollutant concentration. This approach is only valid in winter time when the pollutant concentrations are less affected by atmospheric chemistry. A model based on the steady-state Reynolds-Averaged Navier-Stokes equations (RANS) and standard k-ɛ turbulence model was used to simulate a set of 16 different inlet wind directions over a real urban area (downtown Pamplona, Spain). The temporal series of NO x and PM 10 and the spatial differences in pollutant concentration of NO 2 and BTEX obtained were in agreement with experimental data. Inside urban canopy, an important influence of urban boundary layer dynamics on the pollutant concentration patterns was observed. Large concentration differences between different zones of the same square were found. This showed that concentration levels measured by an automatic monitoring station depend on its location in the street or square, and a modelling methodology like this is useful to complement the experimental information. On the other hand, this methodology can also be applied to evaluate abatement strategies by redistributing traffic emissions.

  2. Simulation model for longterm management of Avena fatua L. in winter wheat

    Directory of Open Access Journals (Sweden)

    Jäck, Ortrud

    2014-02-01

    Full Text Available Decision support systems (DSS are used for weed control decisions worldwide. Several DSS for weed management have been published. However they mostly rely on full herbicide dosages and do not take weed population dynamics into account. We developed a modular DSS for long-term Avena fatua L. control in winter wheat. The DSS was parameterized with three year field experiment datasets covering yield loss data, densitydependent population dynamics data as well as data on dose dependent herbicide efficacy and dosedependent population dynamics. The DSS aims to control the A. fatua in the long run. Our hypothesis is that the optimized DSS reduces herbicide input while keeping the population density at low level, maintaining high grain yields and net return. The DSS comprises four sub-models calculating crop yield loss, A. fatua population dynamics as well as dose dependent herbicide efficacy and economics of the weed control decision. The economic sub-model calculates net return in dependency of the herbicide dosage and thus the resulting crop yield. First results of a 10-year simulation showed that herbicide input could be reduced by 40% compared to the economic threshold strategy, while the population density of A. fatua is controlled. Up to now the DSS has been parameterized for the herbicides Ralon Super, Axial 50 and Broadway. The results show the great potential of reducing herbicide input and point out the importance of including population dynamics models into DSS.

  3. Predicting Pre-planting Risk of Stagonospora nodorum blotch in Winter Wheat Using Machine Learning Models

    Directory of Open Access Journals (Sweden)

    Lucky eMehra

    2016-03-01

    Full Text Available Pre-planting factors have been associated with the late-season severity of Stagonospora nodorum blotch (SNB, caused by the fungal pathogen Parastagonospora nodorum, in winter wheat (Triticum aestivum. The relative importance of these factors in the risk of SNB has not been determined and this knowledge can facilitate disease management decisions prior to planting of the wheat crop. In this study, we examined the performance of multiple regression (MR and three machine learning algorithms namely artificial neural networks, categorical and regression trees, and random forests (RF in predicting the pre-planting risk of SNB in wheat. Pre-planting factors tested as potential predictor variables were cultivar resistance, latitude, longitude, previous crop, seeding rate, seed treatment, tillage type, and wheat residue. Disease severity assessed at the end of the growing season was used as the response variable. The models were developed using 431 disease cases (unique combinations of predictors collected from 2012 to 2014 and these cases were randomly divided into training, validation, and test datasets. Models were evaluated based on the regression of observed against predicted severity values of SNB, sensitivity-specificity ROC analysis, and the Kappa statistic. A strong relationship was observed between late-season severity of SNB and specific pre-planting factors in which latitude, longitude, wheat residue, and cultivar resistance were the most important predictors. The MR model explained 33% of variability in the data, while machine learning models explained 47 to 79% of the total variability. Similarly, the MR model correctly classified 74% of the disease cases, while machine learning models correctly classified 81 to 83% of these cases. Results show that the RF algorithm, which explained 79% of the variability within the data, was the most accurate in predicting the risk of SNB, with an accuracy rate of 93%. The RF algorithm could allow early

  4. Runoff and nutrient losses during winter periods in cold climates--requirements to nutrient simulation models.

    Science.gov (United States)

    Deelstra, Johannes; Kvaernø, Sigrun H; Granlund, Kirsti; Sileika, Antanas Sigitas; Gaigalis, Kazimieras; Kyllmar, Katarina; Vagstad, Nils

    2009-03-01

    Large areas in Europe may experience frozen soils during winter periods which pose special challenges to modelling. Extensive data are collected in small agricultural catchments in Nordic and Baltic countries. An analysis on measurements, carried out in four small agricultural catchments has shown that a considerable amount of the yearly nutrient loss occurs during the freezing period. A freezing period was defined as the time period indicated by the maximum and minimum points on the cumulative degree-day curve. On average 6-32% of the yearly runoff was generated during this period while N-loss varied from 5-35% and P loss varied from 3-33%. The results indicate that infiltration into frozen soils might occur during the freezing period and that the runoff generating processes, at least during a considerable part of the freezing period, are rather similar compared to the processes outside the freezing period. Freeze-thaw cycles affect the infiltration capacity and aggregate stability, thereby the erosion and nutrient losses. The Norwegian catchment had a high P loss during the freezing period compared to the other catchments, most likely caused by catchment characteristics such as slope, soil types, tillage methods and fertiliser application. It is proposed to use data, collected on small agricultural dominated catchments, in the calibration and validation of watershed management models and to take into account runoff and nutrient loss processes which are representative for cold climates, thereby obtaining reliable results.

  5. Modelling Interception and Transpiration at Monthly Time Steps Introducing Daily Variability through Markov Chains

    NARCIS (Netherlands)

    De Groen, M.M.

    2002-01-01

    This dissertation presents improved equations for monthly water resources models, in particular for interception and transpiration. Most ofthe existing monthly models do not make a distinction between interception and transpiration, while this distinction is very important for management purposes.

  6. Statistical modelling of monthly mean sea level at coastal tide gauge stations along the Indian subcontinent

    Digital Repository Service at National Institute of Oceanography (India)

    Srinivas, K.; Das, V.K.; DineshKumar, P.K.

    This study investigates the suitability of statistical models for their predictive potential for the monthly mean sea level at different stations along the west and east coasts of the Indian subcontinent. Statistical modelling of the monthly mean...

  7. Modeling a typical winter-time dust event over the Arabian Peninsula and the Red Sea

    Directory of Open Access Journals (Sweden)

    S. Kalenderski

    2013-02-01

    Full Text Available We used WRF-Chem, a regional meteorological model coupled with an aerosol-chemistry component, to simulate various aspects of the dust phenomena over the Arabian Peninsula and Red Sea during a typical winter-time dust event that occurred in January 2009. The model predicted that the total amount of emitted dust was 18.3 Tg for the entire dust outburst period and that the two maximum daily rates were ~2.4 Tg day−1 and ~1.5 Tg day−1, corresponding to two periods with the highest aerosol optical depth that were well captured by ground- and satellite-based observations. The model predicted that the dust plume was thick, extensive, and mixed in a deep boundary layer at an altitude of 3–4 km. Its spatial distribution was modeled to be consistent with typical spatial patterns of dust emissions. We utilized MODIS-Aqua and Solar Village AERONET measurements of the aerosol optical depth (AOD to evaluate the radiative impact of aerosols. Our results clearly indicated that the presence of dust particles in the atmosphere caused a significant reduction in the amount of solar radiation reaching the surface during the dust event. We also found that dust aerosols have significant impact on the energy and nutrient balances of the Red Sea. Our results showed that the simulated cooling under the dust plume reached 100 W m−2, which could have profound effects on both the sea surface temperature and circulation. Further analysis of dust generation and its spatial and temporal variability is extremely important for future projections and for better understanding of the climate and ecological history of the Red Sea.

  8. Modeling a typical winter-time dust event over the Arabian Peninsula and the Red Sea

    KAUST Repository

    Kalenderski, Stoitchko

    2013-02-20

    We used WRF-Chem, a regional meteorological model coupled with an aerosol-chemistry component, to simulate various aspects of the dust phenomena over the Arabian Peninsula and Red Sea during a typical winter-time dust event that occurred in January 2009. The model predicted that the total amount of emitted dust was 18.3 Tg for the entire dust outburst period and that the two maximum daily rates were ?2.4 Tg day-1 and ?1.5 Tg day-1, corresponding to two periods with the highest aerosol optical depth that were well captured by ground-and satellite-based observations. The model predicted that the dust plume was thick, extensive, and mixed in a deep boundary layer at an altitude of 3-4 km. Its spatial distribution was modeled to be consistent with typical spatial patterns of dust emissions. We utilized MODIS-Aqua and Solar Village AERONET measurements of the aerosol optical depth (AOD) to evaluate the radiative impact of aerosols. Our results clearly indicated that the presence of dust particles in the atmosphere caused a significant reduction in the amount of solar radiation reaching the surface during the dust event. We also found that dust aerosols have significant impact on the energy and nutrient balances of the Red Sea. Our results showed that the simulated cooling under the dust plume reached 100 W m-2, which could have profound effects on both the sea surface temperature and circulation. Further analysis of dust generation and its spatial and temporal variability is extremely important for future projections and for better understanding of the climate and ecological history of the Red Sea.

  9. A seasonal periodic long memory model for monthly river flows

    NARCIS (Netherlands)

    M. Ooms (Marius); Ph.H.B.F. Franses (Philip Hans)

    1998-01-01

    textabstractBased on simple time series plots and periodic sample autocorrelations, we document that monthly river flow data display long memory, in addition to pronounced seasonality. In fact, it appears that the long memory characteristics vary with the season. To describe these two properties

  10. Impacts of +2 °C global warming on winter tourism demand in Europe

    OpenAIRE

    Damm, Andrea; Greuell, Wouter; Landgren, Oskar; Prettenthaler, Franz

    2017-01-01

    Increasing temperatures and snow scarce winter seasons challenge the winter tourism industry. In this study the impacts of +2 °C global warming on winter tourism demand in Europe’s ski tourism related NUTS-3 regions are quantified. Using time series regression models, the relationship between natural snow conditions and monthly overnight stays is estimated. Based on these model results, we quantify the risk of tourism demand losses due to weather variability and assess the potential impacts o...

  11. Impact winter and the Cretaceous/Tertiary extinctions: Results of a Chicxulub asteroid impact model

    Science.gov (United States)

    Pope, Kevin O.; Baines, Kevin H.; Ocampo, Adriana C.; Ivanov, Boris A.

    1994-01-01

    The Chicxulub impact crater in Mexico is the site of the impact purported to have caused mass extinctions at the Cretaceous/Tertiary (K/T) boundary. 2-D hydrocode modeling of the impact, coupled with studies of the impact site geology, indiate that between 0.4 and 7.0 x 10(exp 17) g of sulfur were vaporized by the impact into anhydrite target rocks. A small portion of the sulfur was released as SO3 or SO4, which converted rapidly into H2SO4 aerosol and fell as acid rain. A radiative transfer model, coupled with a model of coagulation indicates that the aerosol prolonged the initial blackout period caused by impact dust only if the aerosol contained impurities. A larger portion of sulfur was released as SO2, which converted to aerosol slowly, due to the rate-limiting oxidation of SO2. Our radiative transfer calculations, combined with rates of acid production, coagulation, and diffusion indicate that solar transmission was reduced to 10-20% of normal for a period of 8-13 yr. This reduction produced a climate forcing (cooling) of -300 W/sq.m, which far exceeded the +8 W/sq.m greenhouse warming, caused by the CO2 released through the vaporization of carbonates, and therefore produced a decade of freezing and near-freezing temperatures. Several decades of moderate warming followed the decade of severe cooling due to the long residence time of CO2. The prolonged impact winter may have been a major cause of the K/T extinctions.

  12. High-resolution boreal winter precipitation projections over tropical America from CMIP5 models

    Science.gov (United States)

    Palomino-Lemus, Reiner; Córdoba-Machado, Samir; Gámiz-Fortis, Sonia Raquel; Castro-Díez, Yolanda; Esteban-Parra, María Jesús

    2017-11-01

    Climate-change projections for boreal winter precipitation in Tropical America has been addressed by statistical downscaling (SD) using the principal component regression with sea-level pressure (SLP) as the predictor variable. The SD model developed from the reanalysis of SLP and gridded precipitation GPCC data, has been applied to SLP outputs from 20 CGMS of CMIP5, both from the present climate (1971-2000) and for the future (2071-2100) under the RCP2.6, RCP4.5, and RCP8.5 scenarios. The SD model shows a suitable performance over large regions, presenting a strong bias only in small areas characterized by very dry climate conditions or poor data coverage. The difference in percentage between the projected SD precipitation and the simulated SD precipitation for present climate, ranges from moderate to intense changes in rainfall (positive or negative, depending on the region and the SD GCM model considered), as the radiative forcing increases from the RCP2.6 to RCP8.5. The disparity in the GCMs outputs seems to be the major source of uncertainty in the projected changes, while the scenario considered appears less decisive. Mexico and eastern Brazil are the areas showing the most coherent decreases between SD GCMs, while northwestern and southeastern South America show consistently significant increases. This coherence is corroborated by the results of the ensemble mean which projects positive changes from 10°N towards the south, with exceptions such as eastern Brazil, northern Chile and some smaller areas, such as the center of Colombia, while projected negative changes are the majority found in the northernmost part.

  13. Monthly water balance model for Ndarugu basin, Kenya | Nyadawa ...

    African Journals Online (AJOL)

    ... model in Ndarugu river basin in Kenya. The model is slightly modified to suit hydrologic conditions in the basin. The study apart from establishing relevant model parameters has recommended optimum length of period for continuous simulation to reduce effect dynamic changes in the basin. Journal of Civil Engineering, ...

  14. A LINKED ANNUAL AND MONTHLY MODEL FOR FORECASTING ALFALFA HAY PRICES

    OpenAIRE

    Blake, Martin J.; Clevenger, Tom

    1984-01-01

    This article develops a model to forecast monthly alfalfa hay prices before the first harvest. This is done by linking an annual model, which forecasts the initial May price, with a system of monthly equations that track the monthly seasonal price pattern, given the forecasted May price.

  15. Modeling turbulent fluxes at a winter wheat stand -possibilities and limitations of ground-based thermography

    Science.gov (United States)

    Ahrends, H. E.; Haseneder-Lind, R.; Schickling, A.; Crewell, S.; Rascher, U.

    2013-12-01

    Aircraft and satellite sensors operating in the thermal infrared (TIR) region of the spectrum provide spatially comprehensive information on the radiometric surface temperature (TR), representing an integrated temperature based on the radiation emitted from different surface components. TR data are commonly applied as a proxy for the (theoretical) aerodynamic temperature, which satisfies the bulk resistance formulation for the sensible heat transport. The quantitative relation between the radiometric and the aerodynamic temperature is however complex and strongly affected by ambient conditions and surface characteristics. Consequently, TR-based estimates of the latent and sensible heat flux can have high levels of uncertainty. Ground-based studies for the validation of remotely sensed TR data and for the evaluation of TR-based models are crucial. Ground-based TIR cameras, allowing for a high observation frequency and for studying the spatial variability of temperatures, might provide a suitable tool for such studies. We aim at testing the limitations and the possibilities of passive ground-based thermography for the application in studies on the diurnal and seasonal changes of land-atmosphere interactions. Operating at a frequency of 5 min., a TIR camera is mounted at a height of 2m at a winter wheat stand (TR32 research site, Germany), capturing images of a 1m x 1m area (320 × 240 pixel) during spring and summer 2013. Radiometric temperatures are corrected for the influence of cloud cover and evaluated using observations from thermocouples (leaf temperature), RTDs (canopy temperature profile) and an IR radiometer (spatially integrated temperature). Simultaneous hyperspectral and sun-induced chlorophyll fluorescence measurements are used as a proxy for plant functioning and status. Spatial image information is integrated into the framework of different flux modeling approaches, ranging from established one-source to complex, multi-layer models. Modelled fluxes are

  16. The influence of winter convection on primary production: a parameterisation using a hydrostatic three-dimensional biogeochemical model

    CERN Document Server

    Große, Fabian; Pätsch, Johannes; Backhaus, Jan O

    2014-01-01

    In the recent past observational and modelling studies have shown that the vertical displacement of water parcels, and therefore, phytoplankton particles in regions of deep-reaching convection plays a key role in late winter/early spring primary production. The underlying mechanism describes how convection cells capture living phytoplankton cells and recurrently expose them to sunlight. This study presents a parameterisation called `phytoconvection' which focuses on the influence of convection on primary production. This parameterisation was implemented into a three-dimensional physical-biogeochemical model and applied to the Northwestern European Continental Shelf and areas of the adjacent Northeast Atlantic. The simulation was compared to a `conventional' parameterisation with respect to its influence on phytoplankton concentrations during the annual cycle and its effect on the carbon cycle. The simulation using the new parameterisation showed good agreement with observation data recorded during winter, whe...

  17. Influence of vitamin D status on respiratory infection incidence and immune function during 4 months of winter training in endurance sport athletes.

    Science.gov (United States)

    He, Cheng-Shiun; Handzlik, Michal; Fraser, William D; Muhamad, Ayu; Preston, Hannah; Richardson, Andrew; Gleeson, Michael

    2013-01-01

    The purpose of this study was to examine the influence of vitamin D status on mucosal and systemic immunity and the incidence, severity and duration of upper respiratory tract illness (URTI) episodes in endurance athletes during a 16-week winter training period. Blood was collected from 225 subjects at the start of the study and plasma was analysed for total 25-hydroxy vitamin D (25(OH)D) and cathelicidin concentration. Blood was also collected at the end of the study and analysed for 25(OH)D and antigen-stimulated cytokine production. Unstimulated saliva samples were obtained at the start and at 4-week intervals during the study period. Saliva samples were analysed for salivary antimicrobial peptides and proteins (AMPs). Weekly training and daily illness logs were kept. At the start and end of the study 38% and 55%, respectively, of the athlete cohort had inadequate (plasma 25(OH)D 30-50 nmol/L) or deficient (plasma 25(OH)D vitamin D status. There was a significantly higher proportion of subjects who presented with symptoms of URTI in the vitamin D deficient status group (initial plasma 25(OH)D vitamin D group (> 120 nmol/L) and the total number of URTI symptom days and the median symptom-severity score in the vitamin D deficient group was signifi- cantly higher than in the other groups. The plasma cathelicidin concentration positively correlated with the plasma 25(OH)D concentration and the saliva secretory immunoglobulin A (SIgA) secretion rate in the optimal vitamin D status group was significantly higher than in the other groups. Low vitamin D status was associated with lower pro-inflammatory cytokine production by monocytes and lymphocytes. Low vitamin D status could be an important determinant of URTI risk in endurance athletes and mucosal as well as systemic immunity may be modified via vitamin D-dependent mechanisms.

  18. The Wintertime Fate of N2O5: Observations and Box Model Analysis for the 2015 WINTER Aircraft Campaign

    Science.gov (United States)

    McDuffie, E. E.; Fibiger, D. L.; Dubé, W.; Lopez-Hilfiker, F.; Thornton, J. A.; Shah, V.; Jaegle, L.; Guo, H.; Weber, R. J.; Campuzano-Jost, P.; Schroder, J. C.; Jimenez, J. L.; Brown, S. S.

    2016-12-01

    Tropospheric ozone (O3) is a regulated secondary pollutant that degrades regional air quality and impacts the oxidizing capacity of the atmosphere. Anthropogenic NOx emissions and chemistry are an important regional O3 source during midlatitude summer, but may destroy O3 during winter. The majority of previous field studies have focused on understanding reactive NOx-O3 relationships under summertime conditions. However, outstanding scientific uncertainties remain regarding the influence of NOx on wintertime O3, in part because the relevant atmospheric chemistry occurs largely at night, and in part because it involves multiphase processes. The winter tropospheric O3 and NOx budgets depend critically on the efficiency of N2O5 uptake to aerosol and the subsequent branching of its reaction products between soluble nitrate (HNO3) and nitryl chloride (ClNO2). The fate of tropospheric N2O5 can lead to net O3 destruction through HNO3 production, or transport and regeneration from N2O5 and ClNO2, which serve as NOx reservoirs. The WINTER campaign has provided the first aircraft measurements to constrain these critically important processes during the winter season. The Wintertime Investigation of Transport, Emission, and Reactivity (WINTER) campaign conducted 13 research flights over the eastern US in February and March 2015. A wide variety of environments were sampled during 11 nighttime flights over continental and marine environments. Reactive nitrogen and ozone measurements were collected with a cavity ring down spectrometer, while HNO3 and ClNO2 were measured with chemical ionization mass spectrometry. Analysis of these data with a chemical box model provides quantitative determinations of the N2O5 aerosol reactive uptake coefficient and production yield of ClNO2. The analysis determines the range and variability in these quantities, and their relationship to air mass composition and meteorology.

  19. Winter Dew Harvest in Mexico City

    Directory of Open Access Journals (Sweden)

    Arias-Torres Jorge Ernesto

    2015-12-01

    Full Text Available This study presents experimental and theoretical results of winter dew harvest in México City in terms of condensation rate. A simplified theoretical model based on a steady-state energy balance on a radiator-condenser was fitted, as a function of the ambient temperature, the relative humidity and the wind velocity. A glass sheet and aluminum sheet white-painted were used as samples over the outdoor experiments. A good correlation was obtained between the theoretical and experimental data. The experimental results show that there was condensation in 68% of the winter nights on both condensers. The total winter condensed mass was 2977 g/m2 and 2888 g/m2 on the glass sheet and aluminum sheet white-painted, respectively. Thus, the condensed mass on the glass was only 3% higher than that on the painted surface. The maximum nightly dew harvests occurred during December, which linearly reduced from 50 g/m2 night to 22 g/m2 night as the winter months went by. The condensation occurred from 1:00 a.m. to 9:00 a.m., with maximum condensation rates between 6:00 a.m. and 7:00 a.m. The dew harvest can provide a partial alternative to the winter water shortage in certain locations with similar climates to the winter in Mexico City, as long as pollution is not significant.

  20. Predicting pre-planting risk of Stagonospora nodorum blotch in winter wheat using machine learning models

    Science.gov (United States)

    Pre-planting factors have been associated with the late-season severity of Stagonospora nodorum blotch (SNB), caused by the fungal pathogen Parastagonospora nodorum, in winter wheat (Triticum aestivum). The relative importance of these factors in the risk of SNB has not been determined and this know...

  1. Winter-Deciduous versus Evergreen Habit in Mediterranean Regions: A Model

    Science.gov (United States)

    Mark A. Blumler

    1991-01-01

    Although winter-deciduous species are presumed to be "out-of-phase" with the mediterranean climate regime, distributional evidence suggests some taxa may be more tolerant of summer drought than evergreen sclerophylls. Deciduous species possess several features that confer advantage in extreme summer dry regions: drought-deciduousness, an efficient response to...

  2. Employment and winter construction

    DEFF Research Database (Denmark)

    Hansen, Ernst Jan de Place; Larsen, Jacob Norvig

    2011-01-01

    hemisphere. Can climatic conditions alone explain the sizeable difference in reduction in building activity in the construction sector in European countries in the winter months, or are other factors such as technology, economic cycles and schemes for financial compensation influential as well? What...... of contracts for workers is more likely to explain differences in seasonal activity than climatic or technological factors....

  3. Simulation of Wild oat (Avena ludoviciana L. Competition on Winter Wheat (Triticum astivum Growth and Yield. I: Model Description and Validation

    Directory of Open Access Journals (Sweden)

    F Mondani

    2015-09-01

    Full Text Available Crop growth models could stimulate growth and development based on science principles and mathematical equations. They also able to evaluate effects of climate, soil, water and agronomic management practices on crop yield. In the present study, an eco-physiological simulation model developed to assess wild oat damage to winter wheat growth and yield. The general structure of this model is derived from LINTUL1 model which modified to wild oat competition against winter wheat. LINTUL1 model was developed for simulation of spring wheat potential production level. In this study, first, we added development stage (DVS and vernalization to LINTUL1 for simulation of winter wheat growth and development and then the model calibrated for potential production level. Finally, we incorporate harmful effects of wild oat to winter wheat growth and yield. Weather data used as input were average daily minimum and maximum temperature (°C and daily global radiation (MJ m-2 in Mashhad, Iran. Parameter values were derived from the literature. The model is written in Fortran Simulation Translator (FST programming language and then validated based on an experiment data. For these purposes different wild oat plant densities were arranged. The data of this experiment does not use for calibration. The results showed that this model was in general able to simulate the temporal changes in DVS of winter wheat and wild oat, total dry matter (TDM of winter wheat and wild oat and yield loss of wheat due to wild oat competition in all treatments, satisfactorily. Root mean square error (RMSE for winter wheat DVS, wild oat DVS, average winter wheat TDM, average wild oat TDM, and yield loss of winter wheat was 10.4, 14.5, 5.8, 7.6 and 7.5, respectively.

  4. The Year Without a Ski Season: An Analysis of the Winter of 2015 for Three Ski Resorts in Western Canada Using Historical and Simulation Model Forecasted Climate Data

    Science.gov (United States)

    Pidwirny, M. J.; Goode, J. D.; Pedersen, S.

    2015-12-01

    The winter of 2015 will go down as "the year without a ski season" for many ski resorts located close to the west coast of Canada and the USA. During this winter season, a large area of the eastern North Pacific Ocean had extremely high sea surface temperatures. These high sea surface temperatures influenced weather patterns on the west coast of North America producing very mild temperatures inland. Further, in alpine environments precipitation that normally arrives in the form of snow instead fell as rain. This research examines the climate characteristics of the winter of 2015 in greater detail for three ski resorts in British Columbia, Canada: Mount Washington, Cypress Mountain and Hemlock Valley. For these resorts, historical (1901 to 2013) and IPCC AR5 climate model forecasted climate data (RCP8.5 for 2025, 2055, and 2085) was generated for the variable winter degree days < 0°C (a measure of winter season coldness) using the spatially interpolated climate database ClimateBC. A value for winter degree days < 0°C was also estimated from recorded climate data at nearby meteorological stations for comparative analysis. For all three resorts, the winter of 2015 proved to be warmer than any individual year in the period 1901 to 2013. Interpolations involving the multi-model ensemble forecast means suggest that the climate associated with winter of 2015 will become the average normal for these resorts in only 35 to 45 years under the RCP8.5 emission scenario.

  5. Analysis of frequency and intensity of European winter storm events from a multi-model perspective, at synoptic and regional scales

    OpenAIRE

    G. C. Leckebusch; Koffi, B.; Ulbrich, U.; Pinto, Joaquim G.; Spangehl, T.; Zacharias, S.

    2006-01-01

    This study focuses on the analysis of winter (October-November-December-January-February-March; ONDJFM) storm events and their changes due to increased anthropogenic greenhouse gas concentrations over Europe. In order to assess uncertainties that are due to model formulation, 4 regional climate models (RCMs) with 5 high resolution experiments, and 4 global general circulation models (GCMs) are considered. Firstly, cyclone systems as synoptic scale processes in winter are investigated, as they...

  6. Yield response of winter wheat cultivars to environments modeled by different variance-covariance structures in linear mixed models

    Energy Technology Data Exchange (ETDEWEB)

    Studnicki, M.; Mądry, W.; Noras, K.; Wójcik-Gront, E.; Gacek, E.

    2016-11-01

    The main objectives of multi-environmental trials (METs) are to assess cultivar adaptation patterns under different environmental conditions and to investigate genotype by environment (G×E) interactions. Linear mixed models (LMMs) with more complex variance-covariance structures have become recognized and widely used for analyzing METs data. Best practice in METs analysis is to carry out a comparison of competing models with different variance-covariance structures. Improperly chosen variance-covariance structures may lead to biased estimation of means resulting in incorrect conclusions. In this work we focused on adaptive response of cultivars on the environments modeled by the LMMs with different variance-covariance structures. We identified possible limitations of inference when using an inadequate variance-covariance structure. In the presented study we used the dataset on grain yield for 63 winter wheat cultivars, evaluated across 18 locations, during three growing seasons (2008/2009-2010/2011) from the Polish Post-registration Variety Testing System. For the evaluation of variance-covariance structures and the description of cultivars adaptation to environments, we calculated adjusted means for the combination of cultivar and location in models with different variance-covariance structures. We concluded that in order to fully describe cultivars adaptive patterns modelers should use the unrestricted variance-covariance structure. The restricted compound symmetry structure may interfere with proper interpretation of cultivars adaptive patterns. We found, that the factor-analytic structure is also a good tool to describe cultivars reaction on environments, and it can be successfully used in METs data after determining the optimal component number for each dataset. (Author)

  7. Yield response of winter wheat cultivars to environments modeled by different variance-covariance structures in linear mixed models

    Directory of Open Access Journals (Sweden)

    Marcin Studnicki

    2016-06-01

    Full Text Available The main objectives of multi-environmental trials (METs are to assess cultivar adaptation patterns under different environmental conditions and to investigate genotype by environment (G×E interactions. Linear mixed models (LMMs with more complex variance-covariance structures have become recognized and widely used for analyzing METs data. Best practice in METs analysis is to carry out a comparison of competing models with different variance-covariance structures. Improperly chosen variance-covariance structures may lead to biased estimation of means resulting in incorrect conclusions. In this work we focused on adaptive response of cultivars on the environments modeled by the LMMs with different variance-covariance structures. We identified possible limitations of inference when using an inadequate variance-covariance structure. In the presented study we used the dataset on grain yield for 63 winter wheat cultivars, evaluated across 18 locations, during three growing seasons (2008/2009-2010/2011 from the Polish Post-registration Variety Testing System. For the evaluation of variance-covariance structures and the description of cultivars adaptation to environments, we calculated adjusted means for the combination of cultivar and location in models with different variance-covariance structures. We concluded that in order to fully describe cultivars adaptive patterns modelers should use the unrestricted variance-covariance structure. The restricted compound symmetry structure may interfere with proper interpretation of cultivars adaptive patterns. We found, that the factor-analytic structure is also a good tool to describe cultivars reaction on environments, and it can be successfully used in METs data after determining the optimal component number for each dataset.

  8. Improving winter leaf area index estimation in evergreen coniferous forests and its significance in carbon and water fluxes modeling

    Science.gov (United States)

    Wang, R.; Chen, J. M.; Luo, X.

    2016-12-01

    Modeling of carbon and water fluxes at the continental and global scales requires remotely sensed LAI as inputs. For evergreen coniferous forests (ENF), severely underestimated winter LAI has been one of the issues for mostly available remote sensing products, which could cause negative bias in the modeling of Gross Primary Productivity (GPP) and evapotranspiration (ET). Unlike deciduous trees which shed all the leaves in winter, conifers retains part of their needles and the proportion of the retained needles depends on the needle longevity. In this work, the Boreal Ecosystem Productivity Simulator (BEPS) was used to model GPP and ET at eight FLUXNET Canada ENF sites. Two sets of LAI were used as the model inputs: the 250m 10-day University of Toronto (U of T) LAI product Version 2 and the corrected LAI based on the U of T LAI product and the needle longevity of the corresponding tree species at individual sites. Validating model daily GPP (gC/m2) against site measurements, the mean RMSE over eight sites decreases from 1.85 to 1.15, and the bias changes from -0.99 to -0.19. For daily ET (mm), mean RMSE decreases from 0.63 to 0.33, and the bias changes from -0.31 to -0.16. Most of the improvements occur in the beginning and at the end of the growing season when there is large correction of LAI and meanwhile temperature is still suitable for photosynthesis and transpiration. For the dormant season, the improvement in ET simulation mostly comes from the increased interception of precipitation brought by the elevated LAI during that time. The results indicate that model performance can be improved by the application the corrected LAI. Improving the winter RS LAI can make a large impact on land surface carbon and energy budget.

  9. The 2009–2010 Arctic stratospheric winter – general evolution, mountain waves and predictability of an operational weather forecast model

    Directory of Open Access Journals (Sweden)

    A. Dörnbrack

    2012-04-01

    Full Text Available The relatively warm 2009–2010 Arctic winter was an exceptional one as the North Atlantic Oscillation index attained persistent extreme negative values. Here, selected aspects of the Arctic stratosphere during this winter inspired by the analysis of the international field experiment RECONCILE are presented. First of all, and as a kind of reference, the evolution of the polar vortex in its different phases is documented. Special emphasis is put on explaining the formation of the exceptionally cold vortex in mid winter after a sequence of stratospheric disturbances which were caused by upward propagating planetary waves. A major sudden stratospheric warming (SSW occurring near the end of January 2010 concluded the anomalous cold vortex period. Wave ice polar stratospheric clouds were frequently observed by spaceborne remote-sensing instruments over the Arctic during the cold period in January 2010. Here, one such case observed over Greenland is analysed in more detail and an attempt is made to correlate flow information of an operational numerical weather prediction model to the magnitude of the mountain-wave induced temperature fluctuations. Finally, it is shown that the forecasts of the ECMWF ensemble prediction system for the onset of the major SSW were very skilful and the ensemble spread was very small. However, the ensemble spread increased dramatically after the major SSW, displaying the strong non-linearity and internal variability involved in the SSW event.

  10. Modeling the Monthly Water Balance of a First Order Coastal Forested Watershed

    Science.gov (United States)

    S. V. Harder; Devendra M. Amatya; T. J. Callahan; Carl C. Trettin

    2006-01-01

    A study has been conducted to evaluate a spreadsheet-based conceptual Thornthwaite monthly water balance model and the process-based DRAINMOD model for their reliability in predicting monthly water budgets of a poorly drained, first order forested watershed at the Santee Experimental Forest located along the Lower Coastal Plain of South Carolina. Measured precipitation...

  11. Simulation of winter wheat yield and its variability in different climates of Europe: A comparison of eight crop growth models

    DEFF Research Database (Denmark)

    Palosuo, Taru; Kersebaum, Kurt Christian; Angulo, Carlos

    2011-01-01

    We compared the performance of eight widely used, easily accessible and well-documented crop growth simulation models (APES, CROPSYST, DAISY, DSSAT, FASSET, HERMES, STICS and WOFOST) for winter wheat (Triticum aestivum L.) during 49 growing seasons at eight sites in northwestern, Central and sout......We compared the performance of eight widely used, easily accessible and well-documented crop growth simulation models (APES, CROPSYST, DAISY, DSSAT, FASSET, HERMES, STICS and WOFOST) for winter wheat (Triticum aestivum L.) during 49 growing seasons at eight sites in northwestern, Central...... to this type of model application. Data used in the simulations consisted of daily weather statistics, information on soil properties, information on crop phenology for each cultivar, and basic crop and soil management information. Our results showed that none of the models perfectly reproduced recorded...... values. In spite of phenological observations being provided, the calibration results for wheat phenology, i.e. estimated dates of anthesis and maturity, were surprisingly variable, with the largest RMSE for anthesis being generated by APES (20.2 days) and for maturity by HERMES (12.6). The wide range...

  12. Short communication: Evaluation of a model for predicting Avena fatua and Descurainia sophia seed emergence in winter rapeseed

    Directory of Open Access Journals (Sweden)

    Mohammad A. Aboutalebian

    2017-07-01

    Full Text Available Avena fatua and Descurainia sophia are two important annual weeds throughout winter rapeseed (Brassica napus L. production systems in the semiarid region of Iran. Timely and more accurate control of both species may be developed if there is a better understanding of its emergence patterns. Non-linear regression techniques are usually unable to accurately predict field emergence under such environmental conditions. The objectives of this research were to evaluate the emergence patterns of A. fatua and D. sophia and determine if emergence could be predicted using cumulative soil thermal time in degree days (CTT. In the present work, cumulative seedling emergence from a winter rapeseed field during 3 years data set was fitted to cumulative soil CTT using Weibull and Gompertz functions. The Weibull model provided a better fit, based on coefficient of determination (R2sqr, root mean square of error (RMSE and Akaike index (AICd, compared to the Gompertz model between 2013 and 2016 seasons for both species. Maximum emergence of A. fatua occured 70-119 days after sowing or after equals 329-426 °Cd, while in D. sophia it occurred 119-134 days after sowing rapeseed equals 373-470 °Cd. Both models can aid in the future study of A. fatua and D. sophia emergence and assist growers and agricultural professionals with planning timely and more accurate A. fatua and D. sophia control.

  13. North American Multi Model Ensemble (NMME) Performance of Monthly Precipitation Forecast over South Sulawesi, Indonesia

    Science.gov (United States)

    Setiawan, A. M.; Koesmaryono, Y.; Faqih, A.; Gunawan, D.

    2017-03-01

    The North American Multi-Model Ensemble (NMME) as one of the multi-model seasonal forecasting system, regularly generate monthly precipitation forecast for all globe with 0.5 - 11.5 months lead time. This useful information can be used as general input to regional and local precipitation forecast. This study quantifies monthly precipitation hindcast data performance in South Sulawesi provided by seven coupled models from the NMME during 29 years (1982 - 2010) period. Climate Hazards Group InfraRed Precipitation with Stations (CHIRPS) dataset and the Standardized Verification System (SVS) for long-range forecasts (LRF) analysis applied to asses monthly precipitation prediction. Almost all individual model shows relatively high skill when used to make June - November monthly precipitation prediction and low skill when used to forecast monthly precipitation in December - May periods. Multi-Model Ensemble (MME) performed using Simple Composite Method (SCM) increased performance of monthly precipitation prediction. Nevertheless, this improvement only applies at short lead time (< 3.3 months). This result also shows that NMME is more promising when it used to make precipitation forecast application during dry period (i.e. drought prediction) rather than wet period over South Sulawesi region.

  14. Monthly Diversions from the Surface-Water Network of the Central Valley Hydrologic Model (CVHM)

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — This digital dataset contains the monthly diversions from the surface-water network for the Central Valley Hydrologic Model (CVHM). The Central Valley encompasses an...

  15. Monthly Precipitation Input Data for the Central Valley Hydrologic Model (CVHM)

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — This digital dataset contains the monthly precipitation for the Central Valley Hydrologic Model (CVHM). The Central Valley encompasses an approximate 50,000...

  16. Monthly inflows to the surface-water network for the Central Valley Hydrologic Model (CVHM)

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — This digital dataset contains the monthly inflows to the surface-water network for the Central Valley Hydrologic Model (CVHM). The Central Valley encompasses an...

  17. Stock assessment for the western winter-spring cohort of neon flying squid (Ommastrephes bartramii using environmentally dependent surplus production models

    Directory of Open Access Journals (Sweden)

    Jintao Wang

    2016-03-01

    Full Text Available The western winter-spring cohort of neon flying squid, Ommastrephes bartramii, is targeted by Chinese squidjigging fisheries in the northwest Pacific from August to November. Because this squid has a short lifespan and is an ecological opportunist, the dynamics of its stock is greatly influenced by the environmental conditions, which need to be considered in its assessment and management. In this study, an environmentally dependent surplus production (EDSP model was developed to evaluate the stock dynamics of O. bartramii. Temporal variability of favourable spawning habitat with sea surface temperature (SST of 21-25°C (Ps was assumed to influence carrying capacity (K, while temporal variability in favourable feeding habitat areas with different SST ranges in different months (Pf was assumed to influence intrinsic growth rate (r. The parameters K and r in the EDSP model were thus assumed to be linked to temporal variability in the proportion of Ps and Pf, respectively. According to Deviance Information Criterion values, the estimated EDSP model with Ps was considered to be better than the conventional surplus production model or other EDSP models. For this model, the maximum sustainable yield (MSY varied from 210000 to 262500 t and biomass at MSY level varied from 360000 to 450000 t. The fishing mortality rates of O. bartramii from 2003 to 2013 were much lower than the fishing mortality at target level and MSY level (Ftar and FMSY and stock biomass was higher than BMSY, suggesting that this squid was not in the status of overfishing and stock was not overfished. The management reference points in the EDSP model for O. bartramii were more conservative than those in the conventional model. This study suggests that the environmental conditions on the spawning grounds should be considered in squid stock assessment and management in the northwest Pacific Ocean.

  18. Realizing User-Relevant Conceptual Model for the Ski Jump Venue of the Vancouver 2010 Winter Olympics

    Science.gov (United States)

    Teakles, Andrew; Mo, Ruping; Dierking, Carl F.; Emond, Chris; Smith, Trevor; McLennan, Neil; Joe, Paul I.

    2014-01-01

    As was the case for most other Olympic competitions, providing weather guidance for the ski jump and Nordic combined events involved its own set of unique challenges. The extent of these challenges was brought to light before the Vancouver 2010 Winter Olympics during a series of outflow wind events in the 2008/2009 winter season. The interactions with the race officials during the difficult race conditions brought on by the outflows provided a new perspective on the service delivery requirements for the upcoming Olympic Games. In particular, the turbulent nature of the winds and its impact on the ski jump practice events that season highlighted the need of race officials for nowcasting advice at very short time scales (from 2 min to 1 h) and forecast products tailored to their decision-making process. These realizations resulted in last minute modifications to the monitoring strategy leading up to the Olympic Games and required forecasters' conceptual models for flow within the Callaghan Valley to be downscaled further to reflect the evolution of turbulence at the ski jump site. The SNOW-V10 (Science of Nowcasting Olympic Weather for Vancouver 2010) team provided support for these efforts by supplying diagnostic case analyses of important events using numerical weather data and by enhancing the real-time monitoring capabilities at the ski jump venue.

  19. Unexpected winter phytoplankton blooms in the North Atlantic subpolar gyre

    Science.gov (United States)

    Lacour, L.; Ardyna, M.; Stec, K. F.; Claustre, H.; Prieur, L.; Poteau, A.; D'Alcala, M. Ribera; Iudicone, D.

    2017-11-01

    In mid- and high-latitude oceans, winter surface cooling and strong winds drive turbulent mixing that carries phytoplankton to depths of several hundred metres, well below the sunlit layer. This downward mixing, in combination with low solar radiation, drastically limits phytoplankton growth during the winter, especially that of the diatoms and other species that are involved in seeding the spring bloom. Here we present observational evidence for widespread winter phytoplankton blooms in a large part of the North Atlantic subpolar gyre from autonomous profiling floats equipped with biogeochemical sensors. These blooms were triggered by intermittent restratification of the mixed layer when mixed-layer eddies led to a horizontal transport of lighter water over denser layers. Combining a bio-optical index with complementary chemotaxonomic and modelling approaches, we show that these restratification events increase phytoplankton residence time in the sunlight zone, resulting in greater light interception and the emergence of winter blooms. Restratification also caused a phytoplankton community shift from pico- and nanophytoplankton to phototrophic diatoms. We conclude that transient winter blooms can maintain active diatom populations throughout the winter months, directly seeding the spring bloom and potentially making a significant contribution to over-winter carbon export.

  20. Estimation of Winter Wheat Biomass and Yield by Combining the AquaCrop Model and Field Hyperspectral Data

    Directory of Open Access Journals (Sweden)

    Xiuliang Jin

    2016-11-01

    Full Text Available Knowledge of spatial and temporal variations in crop growth is important for crop management and stable crop production for the food security of a country. A combination of crop growth models and remote sensing data is a useful method for monitoring crop growth status and estimating crop yield. The objective of this study was to use spectral-based biomass values generated from spectral indices to calibrate the AquaCrop model using the particle swarm optimization (PSO algorithm to improve biomass and yield estimations. Spectral reflectance and concurrent biomass and yield were measured at the Xiaotangshan experimental site in Beijing, China, during four winter wheat-growing seasons. The results showed that all of the measured spectral indices were correlated with biomass to varying degrees. The normalized difference matter index (NDMI was the best spectral index for estimating biomass, with the coefficient of determination (R2, root mean square error (RMSE, and relative RMSE (RRMSE values of 0.77, 1.80 ton/ha, and 25.75%, respectively. The data assimilation method (R2 = 0.83, RMSE = 1.65 ton/ha, and RRMSE = 23.60% achieved the most accurate biomass estimations compared with the spectral index method. The estimated yield was in good agreement with the measured yield (R2 = 0.82, RMSE = 0.55 ton/ha, and RRMSE = 8.77%. This study offers a new method for agricultural resource management through consistent assessments of winter wheat biomass and yield based on the AquaCrop model and remote sensing data.

  1. Predicting monthly precipitation along coastal Ecuador: ENSO and transfer function models

    Science.gov (United States)

    de Guenni, Lelys B.; García, Mariangel; Muñoz, Ángel G.; Santos, José L.; Cedeño, Alexandra; Perugachi, Carlos; Castillo, José

    2017-08-01

    It is well known that El Niño-Southern Oscillation (ENSO) modifies precipitation patterns in several parts of the world. One of the most impacted areas is the western coast of South America, where Ecuador is located. El Niño events that occurred in 1982-1983, 1987-1988, 1991-1992, and 1997-1998 produced important positive rainfall anomalies in the coastal zone of Ecuador, bringing considerable damage to livelihoods, agriculture, and infrastructure. Operational climate forecasts in the region provide only seasonal scale (e.g., 3-month averages) information, but during ENSO events it is key for decision-makers to use reliable sub-seasonal scale forecasts, which at the present time are still non-existent in most parts of the world. This study analyzes the potential predictability of coastal Ecuador rainfall at monthly scale. Instead of the discrete approach that considers training models using only particular seasons, continuous (i.e., all available months are used) transfer function models are built using standard ENSO indices to explore rainfall forecast skill along the Ecuadorian coast and Galápagos Islands. The modeling approach considers a large-scale contribution, represented by the role of a sea-surface temperature index, and a local-scale contribution represented here via the use of previous precipitation observed in the same station. The study found that the Niño3 index is the best ENSO predictor of monthly coastal rainfall, with a lagged response varying from 0 months (simultaneous) for Galápagos up to 3 months for the continental locations considered. Model validation indicates that the skill is similar to the one obtained using principal component regression models for the same kind of experiments. It is suggested that the proposed approach could provide skillful rainfall forecasts at monthly scale for up to a few months in advance.

  2. NASA Ocean Biogeochemical Model assimilating ESRID data global monthly 2/3x1.25 degrees VR2014

    Data.gov (United States)

    National Aeronautics and Space Administration — NASA Ocean Biogeochemical Model -- Assimilated Monthly Data The NASA Ocean Biogeochemical Model (NOBM) is a comprehensive, interactive ocean biogeochemical model...

  3. Winter wheat yield estimation of remote sensing research based on WOFOST crop model and leaf area index assimilation

    Science.gov (United States)

    Chen, Yanling; Gong, Adu; Li, Jing; Wang, Jingmei

    2017-04-01

    Accurate crop growth monitoring and yield predictive information are significant to improve the sustainable development of agriculture and ensure the security of national food. Remote sensing observation and crop growth simulation models are two new technologies, which have highly potential applications in crop growth monitoring and yield forecasting in recent years. However, both of them have limitations in mechanism or regional application respectively. Remote sensing information can not reveal crop growth and development, inner mechanism of yield formation and the affection of environmental meteorological conditions. Crop growth simulation models have difficulties in obtaining data and parameterization from single-point to regional application. In order to make good use of the advantages of these two technologies, the coupling technique of remote sensing information and crop growth simulation models has been studied. Filtering and optimizing model parameters are key to yield estimation by remote sensing and crop model based on regional crop assimilation. Winter wheat of GaoCheng was selected as the experiment object in this paper. And then the essential data was collected, such as biochemical data and farmland environmental data and meteorological data about several critical growing periods. Meanwhile, the image of environmental mitigation small satellite HJ-CCD was obtained. In this paper, research work and major conclusions are as follows. (1) Seven vegetation indexes were selected to retrieve LAI, and then linear regression model was built up between each of these indexes and the measured LAI. The result shows that the accuracy of EVI model was the highest (R2=0.964 at anthesis stage and R2=0.920 at filling stage). Thus, EVI as the most optimal vegetation index to predict LAI in this paper. (2) EFAST method was adopted in this paper to conduct the sensitive analysis to the 26 initial parameters of the WOFOST model and then a sensitivity index was constructed

  4. Editorial - The winter Atomiades

    CERN Multimedia

    Staff Association

    2011-01-01

    As we wrote in our previous editorial, the Staff Association gives direct support to sports events, such as the Atomiades, a section of the Association of Sports Communities of European Research Institutes, which brings together sportsmen and women from 38 European research centres in 13 countries (Austria, Belgium, Czech Republic, United Kingdom, Finland, France, Germany, Hungary, Italy, Luxemburg, the Netherlands, Russia, and Switzerland). The summer Atomiades take place between the months of June and September every three years. Thirteen such events have taken place since 1973, the last one in June 2009 in Berlin. As far as the winter Atomiades are concerned, also organized every three years, and alternating with the summer Atomiades, there have been eleven since 1981, the last one at the end of January this year in neighbouring France. The following article tells the wonderful adventure of the CERN staff who took part in this event. A positive outcome for CERN skiers at the winter Atomiades The 11t...

  5. An assessment of Box-Jenkins models: Forcados monthly rainfall as ...

    African Journals Online (AJOL)

    An autoregressive Box-Jenkins stochastic model of the twelfth order has been developed for the monthly rainfall data for Forcados along the coast of South Eastern Nigeria. The goodness of fit of the model was assessed by estimating the autocorrelations of the residuals of the historical data (from January 1931 to ...

  6. Wildland fire probabilities estimated from weather model-deduced monthly mean fire danger indices

    Science.gov (United States)

    Haiganoush K. Preisler; Shyh-Chin Chen; Francis Fujioka; John W. Benoit; Anthony L. Westerling

    2008-01-01

    The National Fire Danger Rating System indices deduced from a regional simulation weather model were used to estimate probabilities and numbers of large fire events on monthly and 1-degree grid scales. The weather model simulations and forecasts are ongoing experimental products from the Experimental Climate Prediction Center at the Scripps Institution of Oceanography...

  7. Generation of Natural Runoff Monthly Series at Ungauged Sites Using a Regional Regressive Model

    Directory of Open Access Journals (Sweden)

    Dario Pumo

    2016-05-01

    Full Text Available Many hydrologic applications require reliable estimates of runoff in river basins to face the widespread lack of data, both in time and in space. A regional method for the reconstruction of monthly runoff series is here developed and applied to Sicily (Italy. A simple modeling structure is adopted, consisting of a regression-based rainfall–runoff model with four model parameters, calibrated through a two-step procedure. Monthly runoff estimates are based on precipitation, temperature, and exploiting the autocorrelation with runoff at the previous month. Model parameters are assessed by specific regional equations as a function of easily measurable physical and climate basin descriptors. The first calibration step is aimed at the identification of a set of parameters optimizing model performances at the level of single basin. Such “optimal” sets are used at the second step, part of a regional regression analysis, to establish the regional equations for model parameters assessment as a function of basin attributes. All the gauged watersheds across the region have been analyzed, selecting 53 basins for model calibration and using the other six basins exclusively for validation. Performances, quantitatively evaluated by different statistical indexes, demonstrate relevant model ability in reproducing the observed hydrological time-series at both the monthly and coarser time resolutions. The methodology, which is easily transferable to other arid and semi-arid areas, provides a reliable tool for filling/reconstructing runoff time series at any gauged or ungauged basin of a region.

  8. The U.S. Geological Survey Monthly Water Balance Model Futures Portal

    Science.gov (United States)

    Bock, Andrew R.; Hay, Lauren E.; Markstrom, Steven L.; Emmerich, Christopher; Talbert, Marian

    2017-05-03

    The U.S. Geological Survey Monthly Water Balance Model Futures Portal (https://my.usgs.gov/mows/) is a user-friendly interface that summarizes monthly historical and simulated future conditions for seven hydrologic and meteorological variables (actual evapotranspiration, potential evapotranspiration, precipitation, runoff, snow water equivalent, atmospheric temperature, and streamflow) at locations across the conterminous United States (CONUS).The estimates of these hydrologic and meteorological variables were derived using a Monthly Water Balance Model (MWBM), a modular system that simulates monthly estimates of components of the hydrologic cycle using monthly precipitation and atmospheric temperature inputs. Precipitation and atmospheric temperature from 222 climate datasets spanning historical conditions (1952 through 2005) and simulated future conditions (2020 through 2099) were summarized for hydrographic features and used to drive the MWBM for the CONUS. The MWBM input and output variables were organized into an open-access database. An Open Geospatial Consortium, Inc., Web Feature Service allows the querying and identification of hydrographic features across the CONUS. To connect the Web Feature Service to the open-access database, a user interface—the Monthly Water Balance Model Futures Portal—was developed to allow the dynamic generation of summary files and plots  based on plot type, geographic location, specific climate datasets, period of record, MWBM variable, and other options. Both the plots and the data files are made available to the user for download 

  9. Developing empirical monthly groundwater recharge equations based on modeling and remote sensing data - Modeling future groundwater recharge to predict potential climate change impacts

    Science.gov (United States)

    Gemitzi, Alexandra; Ajami, Hoori; Richnow, Hans-Hermann

    2017-03-01

    Groundwater recharge is one of main components of the water budget that is difficult to quantify due to complexity of recharge processes and limited observations. In the present work a simple regression equation for monthly groundwater recharge estimation is developed by relating simulated recharge from a calibrated Soil and Water Assessment tool (SWAT) model to effective precipitation. Monthly groundwater recharge and actual evapotranspiration (AET) were computed by applying a calibrated (SWAT) model for a ten year period (2005-2015) in Vosvozis river basin in NE Greece. SWAT actual evapotranspiration (AET) results were compared to remotely sensed AET values from the MODerate Resolution Imaging Spectroradiometer (MODIS), indicating the integrity of the modeling process. Water isotopes of 2H and 18O, originally presented herein, were used to infer recharge resources in the basin and provided additional evidence of the applicability of the developed formula. Results showed that the developed recharge estimation method can be effectively applied using MODIS evapotranspiration data, without having to adhere to numerical modeling which is many times constrained by the lack of available data especially in poorly gauged basins. Future trends of groundwater recharge up to 2100 using an ensemble of five downscaled climate change projections indicated that annual recharge will increase up to the middle of the present century and gradually decrease thereafter. However, the predicted magnitude is highly variable depending on the Global Climate Model (GCM) used. While winter recharge will likely increase in the future, summer recharge is expected to decrease as a result of temperature rise in the future.

  10. Balance sheet method assessment for nitrogen fertilization in winter wheat: II. alternative strategies using the CropSyst simulation model

    Directory of Open Access Journals (Sweden)

    Maria Corbellini

    2006-09-01

    Full Text Available It is important, both for farmer profit and for the environment, to correctly dose fertilizer nitrogen (N for winter wheat growth. Balance-sheet methods are often used to calculate the recommended dose of N fertilizer. Other methods are based on the dynamic simulation of cropping systems. Aim of the work was to evaluate the balance-sheet method set up by the Region Emilia-Romagna (DPI, by comparing it with the cropping systems simulation model CropSyst (CS, and with an approach based on fixed supplies of N (T. A 3-year trial was structured as a series of N fertility regimes at 3 sites (Papiano di Marsciano, Ravenna, San Pancrazio. The N-regimes were generated at each site-year as separate trials in which 3 N rates were applied: N1 (DPI, N2 (DPI+50 kg ha-1 N at spike initiation, N3 (DPI + 50 kg ha-1 N at early booting. Above ground biomass and soil data (NO3-N and water were sampled and used to calibrate CS. Doses of fertilizer N were calculated by both DPI and CS for winter wheat included in three typical rotations for Central and Northern Italy. Both these methods and method T were simulated at each site over 50 years, by using daily generated weather data. The long-term simulation allowed evaluating such alternative fertilization strategies. DPI and CS estimated comparable crop yields and N leached amounts, and both resulted better than T. Minor risk of leaching emerged for all N doses. The N2 and N3 rates allowed slightly higher crop yields than N1.

  11. A winter distribution model for Bicknell's Thrush (Catharus bicknelli), a conservation tool for a threatened migratory songbird

    Science.gov (United States)

    K. P. McFarland; C. C. Rimmer; J. E. Goetz; Y. Aubry; J. M. Wunderle Jr.; A. Hayes-Sutton; J. M. Townsend; A. Llanes Sosa; A. Kirkconnell

    2013-01-01

    Conservation planning and implementation require identifying pertinent habitats and locations where protection and management may improve viability of targeted species. The winter range of Bicknell’s Thrush (Catharus bicknelli), a threatened Nearctic-Neotropical migratory songbird, is restricted to the Greater Antilles. We analyzed winter records from the mid-1970s to...

  12. Assessing Uncertainties of Water Footprints Using an Ensemble of Crop Growth Models on Winter Wheat

    Directory of Open Access Journals (Sweden)

    Kurt Christian Kersebaum

    2016-12-01

    Full Text Available Crop productivity and water consumption form the basis to calculate the water footprint (WF of a specific crop. Under current climate conditions, calculated evapotranspiration is related to observed crop yields to calculate WF. The assessment of WF under future climate conditions requires the simulation of crop yields adding further uncertainty. To assess the uncertainty of model based assessments of WF, an ensemble of crop models was applied to data from five field experiments across Europe. Only limited data were provided for a rough calibration, which corresponds to a typical situation for regional assessments, where data availability is limited. Up to eight models were applied for wheat. The coefficient of variation for the simulated actual evapotranspiration between models was in the range of 13%–19%, which was higher than the inter-annual variability. Simulated yields showed a higher variability between models in the range of 17%–39%. Models responded differently to elevated CO2 in a FACE (Free-Air Carbon Dioxide Enrichment experiment, especially regarding the reduction of water consumption. The variability of calculated WF between models was in the range of 15%–49%. Yield predictions contributed more to this variance than the estimation of water consumption. Transpiration accounts on average for 51%–68% of the total actual evapotranspiration.

  13. Modelling of air quality for Winter and Summer episodes in Switzerland. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Andreani-Aksoyoglu, S.; Keller, J.; Barmpadimos, L.; Oderbolz, D.; Tinguely, M.; Prevot, A. [Paul Scherrer Institute (PSI), Laboratory of Atmospheric Chemistry, Villigen (Switzerland); Alfarra, R. [University of Manchester, Manchester (United Kingdom); Sandradewi, J. [Jisca Sandradewi, Hoexter (Germany)

    2009-05-15

    This final report issued by the General Energy Research Department and its Laboratory of Atmospheric Chemistry at the Paul Scherrer Institute (PSI) reports on the results obtained from the modelling of regional air quality for three episodes, January-February 2006, June 2006 and January 2007. The focus of the calculations is on particulate matter concentrations, as well as on ozone levels in summer. The model results were compared with the aerosol data collected by an Aerosol Mass Spectrometer (AMS), which was operated during all three episodes as well as with the air quality monitoring data from further monitoring programs. The air quality model used in this study is described and the results obtained for various types of locations - rural, city, high-altitude and motorway-near - are presented and discussed. The models used are described.

  14. WINTER SAECULUM

    Directory of Open Access Journals (Sweden)

    Emil Mihalina

    2017-03-01

    Full Text Available Accumulated imbalances in the economy and on the markets cause specific financial market dynamics that have formed characteristic patterns kept throughout long financial history. In 2008 Authors presented their expectations of key macroeconomic and selected asset class markets developments for period ahead based on Saeculum theory. Use of term Secular describes a specific valuation environment during prolonged period. If valuations as well as selected macro variables are considered as a tool for understanding business cycles then market cycles become much more obvious and easily understandable. Therefore over the long run, certain asset classes do better in terms of risk reward profile than others. Further on, there is no need for frequent portfolio rebalancing and timing of specific investment positions within a particular asset class market. Current stage in cycle development suggests a need for reassessment of trends and prevailing phenomena due to cyclical nture of long lasting Saeculums. Paper reviews developments in recognizable patterns of selected metrics in current Winter Saeculum dominated with prevailing forces of delivering, deflation and decrease in velocity of money.

  15. Coupled climate model simulations of Mediterranean winter cyclones and large-scale flow patterns

    Directory of Open Access Journals (Sweden)

    B. Ziv

    2013-03-01

    Full Text Available The study aims to evaluate the ability of global, coupled climate models to reproduce the synoptic regime of the Mediterranean Basin. The output of simulations of the 9 models included in the IPCC CMIP3 effort is compared to the NCEP-NCAR reanalyzed data for the period 1961–1990. The study examined the spatial distribution of cyclone occurrence, the mean Mediterranean upper- and lower-level troughs, the inter-annual variation and trend in the occurrence of the Mediterranean cyclones, and the main large-scale circulation patterns, represented by rotated EOFs of 500 hPa and sea level pressure. The models reproduce successfully the two maxima in cyclone density in the Mediterranean and their locations, the location of the average upper- and lower-level troughs, the relative inter-annual variation in cyclone occurrences and the structure of the four leading large scale EOFs. The main discrepancy is the models' underestimation of the cyclone density in the Mediterranean, especially in its western part. The models' skill in reproducing the cyclone distribution is found correlated with their spatial resolution, especially in the vertical. The current improvement in model spatial resolution suggests that their ability to reproduce the Mediterranean cyclones would be improved as well.

  16. A Temperature-Based Model for Estimating Monthly Average Daily Global Solar Radiation in China

    Directory of Open Access Journals (Sweden)

    Huashan Li

    2014-01-01

    Full Text Available Since air temperature records are readily available around the world, the models based on air temperature for estimating solar radiation have been widely accepted. In this paper, a new model based on Hargreaves and Samani (HS method for estimating monthly average daily global solar radiation is proposed. With statistical error tests, the performance of the new model is validated by comparing with the HS model and its two modifications (Samani model and Chen model against the measured data at 65 meteorological stations in China. Results show that the new model is more accurate and robust than the HS, Samani, and Chen models in all climatic regions, especially in the humid regions. Hence, the new model can be recommended for estimating solar radiation in areas where only air temperature data are available in China.

  17. A physical-empirical model of the East Asian winter monsoon using Eurasian snow cover and sea surface temperature

    Science.gov (United States)

    Yu, Lulu; Wu, Zhiwei; Zhang, Renhe

    2017-04-01

    Seasonal prediction of the East Asian (EA) winter monsoon (EAWM) is of great significance yet a challenging issue. In this study, three physical-empirical (PE) seasonal prediction models for the EAWM are established using three leading modes of the Eurasian snow cover (ESC), the first leading mode of sea surface temperature (SST) and the first leading mode of the combination of the ESC and SST in preceding autumn, respectively. These leading modes are identified by the partial-least square (PLS) regression. The first PLS (PLS1) mode for the ESC features significantly anomalous snow cover in Siberia and Tibetan Plateau regions. The ESC second PLS (PLS2) mode corresponds to large areas of snow cover anomalies in the central Siberia, whereas the third PLS (PLS3) mode a meridional seesaw pattern of ESC. The SST PLS1 mode basically exhibits an El Niño-Southern Oscillation (ENSO) developing phase in equatorial eastern Pacific and significant SST anomalies in North Atlantic. A strong EAWM tends to emerge in a La Niña year concurrent with cold SST anomalies in the North Atlantic, and vice versa. After a 35-yr training period (1967t2001), three PE seasonal prediction models are constructed and the 13-yr hindcast is performed for the period of 2002t2014, respectively. The PE model based on combination of the autumn ESC and SST exhibits the best hindcast skill among the three models, its correlation coefficient between the observation and the hindcast reaching 0.88. This indicates that this PE model may provide another practical tool for the EAWM. In addition, the relative contribution of the ESC and SST is also examined by assessing the hindcast skills of the other two PE models constructed solely by the ESC or SST. Possible physical mechanisms are also discussed.

  18. Interannual and low-frequency variability of Upper Indus Basin winter/spring precipitation in observations and CMIP5 models

    Science.gov (United States)

    Greene, Arthur M.; Robertson, Andrew W.

    2017-12-01

    An assessment is made of the ability of general circulation models in the CMIP5 ensemble to reproduce observed modes of low-frequency winter/spring precipitation variability in the region of the Upper Indus basin (UIB) in south-central Asia. This season accounts for about two thirds of annual precipitation totals in the UIB and is characterized by "western disturbances" propagating along the eastward extension of the Mediterranean storm track. Observational data are utilized for for spatiotemporal characterization of the precipitation seasonal cycle, to compute seasonalized spectra and finally, to examine teleconnections, in terms of large-scale patterns in sea-surface temperature (SST) and atmospheric circulation. Annual and lowpassed variations are found to be associated primarily with SST modes in the tropical and extratropical Pacific. A more obscure link to North Atlantic SST, possibly related to the North Atlantic Oscillation, is also noted. An ensemble of 31 CMIP5 models is then similarly assessed, using unforced preindustrial multi-century control runs. Of these models, eight are found to reproduce well the two leading modes of the observed seasonal cycle. This model subset is then assessed in the spectral domain and with respect to teleconnection patterns, where a range of behaviors is noted. Two model families each account for three members of this subset. The degree of within-family similarity in behavior is shown to reflect underlying model differences. The results provide estimates of unforced regional hydroclimate variability over the UIB on interannual and decadal scales and the corresponding far-field influences, and are of potential relevance for the estimation of uncertainties in future water availability.

  19. The long-term effect of climate change on productivity of winter wheat in Denmark: a scenario analysis using three crop models

    DEFF Research Database (Denmark)

    Öztürk, Isik; Sharif, Behzad; Baby, Sanmohan

    2017-01-01

    The response of grain yield, grain nitrogen (N), phenological development and evapotranspiration of winter wheat to climate change was analysed over an 80-year period based on climate change predictions of four regional circulation models (RCMs) under the IPCC (International Panel on Climate Change...

  20. Investigating the role of chemical and physical processes on organic aerosol modelling with CAMx in the Po Valley during a winter episode

    Science.gov (United States)

    Meroni, A.; Pirovano, G.; Gilardoni, S.; Lonati, G.; Colombi, C.; Gianelle, V.; Paglione, M.; Poluzzi, V.; Riva, G. M.; Toppetti, A.

    2017-12-01

    Traditional aerosol mechanisms underestimate the observed organic aerosol concentration, especially due to the lack of information on secondary organic aerosol (SOA) formation and processing. In this study we evaluate the chemical and transport model CAMx during a one-month in winter (February 2013) over a 5 km resolution domain, covering the whole Po valley (Northern Italy). This works aims at investigating the effects of chemical and physical atmospheric processing on modelling results and, in particular, to evaluate the CAMx sensitivity to organic aerosol (OA) modelling schemes: we will compare the recent 1.5D-VBS algorithm (CAMx-VBS) with the traditional Odum 2-product model (CAMx-SOAP). Additionally, the thorough diagnostic analysis of the reproduction of meteorology, precursors and aerosol components was intended to point put strength and weaknesses of the modelling system and address its improvement. Firstly, we evaluate model performance for criteria PM concentration. PM10 concentration was underestimated both by CAMx-SOAP and even more by CAMx-VBS, with the latter showing a bias ranging between -4.7 and -7.1 μg m-3. PM2.5 model performance was to some extent better than PM10, showing a mean bias ranging between -0.5 μg m-3 at rural sites and -5.5 μg m-3 at urban and suburban sites. CAMx performance for OA was clearly worse than for the other PM compounds (negative bias ranging between -40% and -75%). The comparisons of model results with OA sources (identified by PMF analysis) shows that the VBS scheme underestimates freshly emitted organic aerosol while SOAP overestimates. The VBS scheme correctly reproduces biomass burning (BBOA) contributions to primary OA concentrations (POA). In contrast VBS slightly underestimates the contribution from fossil-fuel combustion (HOA), indicating that POA emissions related to road transport are either underestimated or associated to higher volatility classes. The VBS scheme under-predictes the SOA too, but to a lesser

  1. Numerical model simulations of boundary-layer dynamics during winter conditions

    DEFF Research Database (Denmark)

    Melas, D.; Persson, T.; Bruin, H. de

    2001-01-01

    A mesoscale numerical model, incorporating a land-surface scheme based on Deardorffs' approach, is used to study the diurnal variation of the boundary layer structure and surface fluxes during four consecutive days with air temperatures well below zero, snow covered ground and changing synoptic f...

  2. Prediction of Monthly Summer Monsoon Rainfall Using Global Climate Models Through Artificial Neural Network Technique

    Science.gov (United States)

    Nair, Archana; Singh, Gurjeet; Mohanty, U. C.

    2018-01-01

    The monthly prediction of summer monsoon rainfall is very challenging because of its complex and chaotic nature. In this study, a non-linear technique known as Artificial Neural Network (ANN) has been employed on the outputs of Global Climate Models (GCMs) to bring out the vagaries inherent in monthly rainfall prediction. The GCMs that are considered in the study are from the International Research Institute (IRI) (2-tier CCM3v6) and the National Centre for Environmental Prediction (Coupled-CFSv2). The ANN technique is applied on different ensemble members of the individual GCMs to obtain monthly scale prediction over India as a whole and over its spatial grid points. In the present study, a double-cross-validation and simple randomization technique was used to avoid the over-fitting during training process of the ANN model. The performance of the ANN-predicted rainfall from GCMs is judged by analysing the absolute error, box plots, percentile and difference in linear error in probability space. Results suggest that there is significant improvement in prediction skill of these GCMs after applying the ANN technique. The performance analysis reveals that the ANN model is able to capture the year to year variations in monsoon months with fairly good accuracy in extreme years as well. ANN model is also able to simulate the correct signs of rainfall anomalies over different spatial points of the Indian domain.

  3. Prediction of Monthly Summer Monsoon Rainfall Using Global Climate Models Through Artificial Neural Network Technique

    Science.gov (United States)

    Nair, Archana; Singh, Gurjeet; Mohanty, U. C.

    2017-08-01

    The monthly prediction of summer monsoon rainfall is very challenging because of its complex and chaotic nature. In this study, a non-linear technique known as Artificial Neural Network (ANN) has been employed on the outputs of Global Climate Models (GCMs) to bring out the vagaries inherent in monthly rainfall prediction. The GCMs that are considered in the study are from the International Research Institute (IRI) (2-tier CCM3v6) and the National Centre for Environmental Prediction (Coupled-CFSv2). The ANN technique is applied on different ensemble members of the individual GCMs to obtain monthly scale prediction over India as a whole and over its spatial grid points. In the present study, a double-cross-validation and simple randomization technique was used to avoid the over-fitting during training process of the ANN model. The performance of the ANN-predicted rainfall from GCMs is judged by analysing the absolute error, box plots, percentile and difference in linear error in probability space. Results suggest that there is significant improvement in prediction skill of these GCMs after applying the ANN technique. The performance analysis reveals that the ANN model is able to capture the year to year variations in monsoon months with fairly good accuracy in extreme years as well. ANN model is also able to simulate the correct signs of rainfall anomalies over different spatial points of the Indian domain.

  4. Statistical model for forecasting monthly large wildfire events in western United States

    Science.gov (United States)

    Haiganoush K. Preisler; Anthony L. Westerling

    2006-01-01

    The ability to forecast the number and location of large wildfire events (with specified confidence bounds) is important to fire managers attempting to allocate and distribute suppression efforts during severe fire seasons. This paper describes the development of a statistical model for assessing the forecasting skills of fire-danger predictors and producing 1-month-...

  5. Daily and monthly temperature and precipitation statistics as performance indicators for regional climate models

    DEFF Research Database (Denmark)

    Kjellström, Erik; Boberg, Fredrik; Castro, Manuel

    2010-01-01

    We evaluated daily and monthly statistics of maximum and minimum temperatures and precipitation in an ensemble of 16 regional climate models (RCMs) forced by boundary conditions from reanalysis data for 1961-1990. A high-resolution gridded observational data set for land areas in Europe was used....

  6. Modeling the winter-to-summer transition of prokaryotic and viral abundance in the Arctic Ocean.

    Science.gov (United States)

    Winter, Christian; Payet, Jérôme P; Suttle, Curtis A

    2012-01-01

    One of the challenges in oceanography is to understand the influence of environmental factors on the abundances of prokaryotes and viruses. Generally, conventional statistical methods resolve trends well, but more complex relationships are difficult to explore. In such cases, Artificial Neural Networks (ANNs) offer an alternative way for data analysis. Here, we developed ANN-based models of prokaryotic and viral abundances in the Arctic Ocean. The models were used to identify the best predictors for prokaryotic and viral abundances including cytometrically-distinguishable populations of prokaryotes (high and low nucleic acid cells) and viruses (high- and low-fluorescent viruses) among salinity, temperature, depth, day length, and the concentration of Chlorophyll-a. The best performing ANNs to model the abundances of high and low nucleic acid cells used temperature and Chl-a as input parameters, while the abundances of high- and low-fluorescent viruses used depth, Chl-a, and day length as input parameters. Decreasing viral abundance with increasing depth and decreasing system productivity was captured well by the ANNs. Despite identifying the same predictors for the two populations of prokaryotes and viruses, respectively, the structure of the best performing ANNs differed between high and low nucleic acid cells and between high- and low-fluorescent viruses. Also, the two prokaryotic and viral groups responded differently to changes in the predictor parameters; hence, the cytometric distinction between these populations is ecologically relevant. The models imply that temperature is the main factor explaining most of the variation in the abundances of high nucleic acid cells and total prokaryotes and that the mechanisms governing the reaction to changes in the environment are distinctly different among the prokaryotic and viral populations.

  7. Comparison of sea ice simulations with interactive and monthly averaged forcing models

    Science.gov (United States)

    Wu, Xingren; Simmonds, Ian; Budd, W. F.

    1996-04-01

    A dynamic-thermodynamic sea ice model is developed and coupled with the "21 wave 9 level" Melbourne University general circulation model to simulate the seasonal cycle of the global sea ice distribution. We have run the coupled system and obtained a creditable seasonal simulation of global sea ice. When monthly averaged atmospheric data (taken from the mean of the coupled run) are used to force the sea ice model, the seasonal cycle of sea ice extent (to the outer ice edge) is quite similar to that simulated in the interactive run. However, the actual sea ice covered area (i.e., excluding leads) differs considerably between the two simulations. Sea ice is more compact in the monthly averaged forced run than in the interactive run throughout the year in both hemispheres. The sea ice thickness distribution also differs between the two runs. In general, the sea ice is more open and thicker in the seasonal ice zone of the two polar regions for the interactive coupled case than for the mean forcing. We have also run the model forced with daily atmospheric data and the simulated sea ice distribution differs significantly from both the interactive model and the monthly averaged forcing results. These differences highlight the dangers of undertaking studies with sea ice models forced with prescribed atmospheric conditions rather than using a fully interactive atmosphere-sea ice system.

  8. Learning at old age: a study on winter bees.

    Science.gov (United States)

    Behrends, Andreas; Scheiner, Ricarda

    2010-01-01

    Ageing is often accompanied by a decline in learning and memory abilities across the animal kingdom. Understanding age-related changes in cognitive abilities is therefore a major goal of current research. The honey bee is emerging as a novel model organism for age-related changes in brain function, because learning and memory can easily be studied in bees under controlled laboratory conditions. In addition, genetically similar workers naturally display life expectancies from 6 weeks (summer bees) to 6 months (winter bees). We studied whether in honey bees, extreme longevity leads to a decline in cognitive functions. Six-month-old winter bees were conditioned either to odours or to tactile stimuli. Afterwards, long-term memory and discrimination abilities were analysed. Winter bees were kept under different conditions (flight/no flight opportunity) to test for effects of foraging activity on learning performance. Despite their extreme age, winter bees did not display an age-related decline in learning or discrimination abilities, but had a slightly impaired olfactory long-term memory. The opportunity to forage indoors led to a slight decrease in learning performance. This suggests that in honey bees, unlike in most other animals, age per se does not impair associative learning. Future research will show which mechanisms protect winter bees from age-related deficits in learning.

  9. Learning at old age: a study on winter bees

    Directory of Open Access Journals (Sweden)

    Andreas Behrends

    2010-04-01

    Full Text Available Ageing is often accompanied by a decline in learning and memory abilities across the animal kingdom. Understanding age-related changes in cognitive abilities is therefore a major goal of current research. The honey bee is emerging as a novel model organism for age-related changes in brain function, because learning and memory can easily be studied in bees under controlled laboratory conditions. In addition, genetically similar workers naturally display life expectancies from six weeks (summer bees to six months (winter bees. We studied whether in honey bees, extreme longevity leads to a decline in cognitive functions. Six-month-old winter bees were conditioned either to odours or to tactile stimuli. Afterwards, long-term memory and discrimination abilities were analysed. Winter bees were kept under different conditions (flight /no flight opportunity to test for effects of foraging activity on learning performance. Despite their extreme age, winter bees did not display an age-related decline in learning or discrimination abilities, but had a slightly impaired olfactory long-term memory. The opportunity to forage indoors led to a slight decrease in learning performance. This suggests that in honey bees, unlike in most other animals, age per se does not impair associative learning. Future research will show which mechanisms protect winter bees from age-related deficits in learning.

  10. Learning at Old Age: A Study on Winter Bees

    Science.gov (United States)

    Behrends, Andreas; Scheiner, Ricarda

    2010-01-01

    Ageing is often accompanied by a decline in learning and memory abilities across the animal kingdom. Understanding age-related changes in cognitive abilities is therefore a major goal of current research. The honey bee is emerging as a novel model organism for age-related changes in brain function, because learning and memory can easily be studied in bees under controlled laboratory conditions. In addition, genetically similar workers naturally display life expectancies from 6 weeks (summer bees) to 6 months (winter bees). We studied whether in honey bees, extreme longevity leads to a decline in cognitive functions. Six-month-old winter bees were conditioned either to odours or to tactile stimuli. Afterwards, long-term memory and discrimination abilities were analysed. Winter bees were kept under different conditions (flight/no flight opportunity) to test for effects of foraging activity on learning performance. Despite their extreme age, winter bees did not display an age-related decline in learning or discrimination abilities, but had a slightly impaired olfactory long-term memory. The opportunity to forage indoors led to a slight decrease in learning performance. This suggests that in honey bees, unlike in most other animals, age per se does not impair associative learning. Future research will show which mechanisms protect winter bees from age-related deficits in learning. PMID:20428511

  11. The Adverse Effect of Spasticity on 3-Month Poststroke Outcome Using a Population-Based Model

    Directory of Open Access Journals (Sweden)

    S. R. Belagaje

    2014-01-01

    Full Text Available Several devices and medications have been used to address poststroke spasticity. Yet, spasticity’s impact on outcomes remains controversial. Using data from a cohort of 460 ischemic stroke patients, we previously published a validated multivariable regression model for predicting 3-month modified Rankin Score (mRS as an indicator of functional outcome. Here, we tested whether including spasticity improved model fit and estimated the effect spasticity had on the outcome. Spasticity was defined by a positive response to the question “Did you have spasticity following your stroke?” on direct interview at 3 months from stroke onset. Patients who had expired by 90 days (n=30 or did not have spasticity data available (n=102 were excluded. Spasticity affected the 3-month functional status (β=0.420, 95 CI=0.194 to 0.645 after accounting for age, diabetes, leukoaraiosis, and retrospective NIHSS. Using spasticity as a covariable, the model’s R2 changed from 0.599 to 0.622. In our model, the presence of spasticity in the cohort was associated with a worsened 3-month mRS by an average of 0.4 after adjusting for known covariables. This significant adverse effect on functional outcomes adds predictive value beyond previously established factors.

  12. Forecasting monthly inflow discharge of the Iffezheim reservoir using data-driven models

    Science.gov (United States)

    Zhang, Qing; Aljoumani, Basem; Hillebrand, Gudrun; Hoffmann, Thomas; Hinkelmann, Reinhard

    2017-04-01

    River stream flow is an essential element in hydrology study fields, especially for reservoir management, since it defines input into reservoirs. Forecasting this stream flow plays an important role in short or long-term planning and management in the reservoir, e.g. optimized reservoir and hydroelectric operation or agricultural irrigation. Highly accurate flow forecasting can significantly reduce economic losses and is always pursued by reservoir operators. Therefore, hydrologic time series forecasting has received tremendous attention of researchers. Many models have been proposed to improve the hydrological forecasting. Due to the fact that most natural phenomena occurring in environmental systems appear to behave in random or probabilistic ways, different cases may need a different methods to forecast the inflow and even a unique treatment to improve the forecast accuracy. The purpose of this study is to determine an appropriate model for forecasting monthly inflow to the Iffezheim reservoir in Germany, which is the last of the barrages in the Upper Rhine. Monthly time series of discharges, measured from 1946 to 2001 at the Plittersdorf station, which is located 6 km downstream of the Iffezheim reservoir, were applied. The accuracies of the used stochastic models - Fiering model and Auto-Regressive Integrated Moving Average models (ARIMA) are compared with Artificial Intelligence (AI) models - single Artificial Neural Network (ANN) and Wavelet ANN models (WANN). The Fiering model is a linear stochastic model and used for generating synthetic monthly data. The basic idea in modeling time series using ARIMA is to identify a simple model with as few model parameters as possible in order to provide a good statistical fit to the data. To identify and fit the ARIMA models, four phase approaches were used: identification, parameter estimation, diagnostic checking, and forecasting. An automatic selection criterion, such as the Akaike information criterion, is utilized

  13. Factors limiting the grain protein content of organic winter wheat in south-eastern France: a mixed-model approach

    NARCIS (Netherlands)

    Casagrande, M.; David, C.; Valantin-Morison, M.; Makowski, D.; Jeuffroy, M.H.

    2009-01-01

    Organic agriculture could achieve the objectives of sustainable agriculture by banning the use of synthetic fertilizers and pesticides. However, organic crops generally show lower performances than conventional ones. In France, organic winter wheat production is characterized by low grain protein

  14. Motor vehicle mpg and market shares report: first six months of model year 1984

    Energy Technology Data Exchange (ETDEWEB)

    Hu, P.S.; Greene, D.L.; Till, L.E.

    1984-10-01

    This issue of the publication reports the sales, market shares, estimated sales-weighted fuel economies, and other estimated sales-weighted vehicle characteristics of automobiles and light trucks for the first six months of model year 1984 and for the previous five model years. Comparisons and observations are made on the trends in these vehicles from one model year to the next. An improved methodology is used to allocate the yearly mpg changes among eight components, rather than the four reported in the previous reports. Sales of automobiles showed an increase of 21.8% from the first half of model year 1983. An even more striking increase was observed in the sales of light trucks: 42.2% from the first half of model year 1983. The first six months of model year 1984 experienced a gain of 0.21 mpg in sales-weighted automobile fuel economy. In contrast, light trucks experienced a loss of 0.83 mpg in fuel economy, from 20.52 mpg in model year 1983 to 19.69 mpg in the first half of model year 1984.

  15. Wavelet-linear genetic programming: A new approach for modeling monthly streamflow

    Science.gov (United States)

    Ravansalar, Masoud; Rajaee, Taher; Kisi, Ozgur

    2017-06-01

    The streamflows are important and effective factors in stream ecosystems and its accurate prediction is an essential and important issue in water resources and environmental engineering systems. A hybrid wavelet-linear genetic programming (WLGP) model, which includes a discrete wavelet transform (DWT) and a linear genetic programming (LGP) to predict the monthly streamflow (Q) in two gauging stations, Pataveh and Shahmokhtar, on the Beshar River at the Yasuj, Iran were used in this study. In the proposed WLGP model, the wavelet analysis was linked to the LGP model where the original time series of streamflow were decomposed into the sub-time series comprising wavelet coefficients. The results were compared with the single LGP, artificial neural network (ANN), a hybrid wavelet-ANN (WANN) and Multi Linear Regression (MLR) models. The comparisons were done by some of the commonly utilized relevant physical statistics. The Nash coefficients (E) were found as 0.877 and 0.817 for the WLGP model, for the Pataveh and Shahmokhtar stations, respectively. The comparison of the results showed that the WLGP model could significantly increase the streamflow prediction accuracy in both stations. Since, the results demonstrate a closer approximation of the peak streamflow values by the WLGP model, this model could be utilized for the simulation of cumulative streamflow data prediction in one month ahead.

  16. A Different View of Solar Spectral Irradiance Variations: Modeling Total Energy over Six-Month Intervals.

    Science.gov (United States)

    Woods, Thomas N; Snow, Martin; Harder, Jerald; Chapman, Gary; Cookson, Angela

    A different approach to studying solar spectral irradiance (SSI) variations, without the need for long-term (multi-year) instrument degradation corrections, is examining the total energy of the irradiance variation during 6-month periods. This duration is selected because a solar active region typically appears suddenly and then takes 5 to 7 months to decay and disperse back into the quiet-Sun network. The solar outburst energy, which is defined as the irradiance integrated over the 6-month period and thus includes the energy from all phases of active region evolution, could be considered the primary cause for the irradiance variations. Because solar cycle variation is the consequence of multiple active region outbursts, understanding the energy spectral variation may provide a reasonable estimate of the variations for the 11-year solar activity cycle. The moderate-term (6-month) variations from the Solar Radiation and Climate Experiment (SORCE) instruments can be decomposed into positive (in-phase with solar cycle) and negative (out-of-phase) contributions by modeling the variations using the San Fernando Observatory (SFO) facular excess and sunspot deficit proxies, respectively. These excess and deficit variations are fit over 6-month intervals every 2 months over the mission, and these fitted variations are then integrated over time for the 6-month energy. The dominant component indicates which wavelengths are in-phase and which are out-of-phase with solar activity. The results from this study indicate out-of-phase variations for the 1400 - 1600 nm range, with all other wavelengths having in-phase variations.

  17. Modeling the Habitat of the Red-Crowned Crane (Grus japonensis Wintering in Cheorwon-Gun to Support Decision Making

    Directory of Open Access Journals (Sweden)

    Ho Gul Kim

    2016-06-01

    Full Text Available Cheorwon-gun is an important wintering area for the red-crowned crane (Grus japonensis. Although eco-tourism has been recently proposed as a means to stimulate the local economy, it may have adverse effects on the crane. We believe a science-based conservation plan is needed to mitigate these negative effects. To this end, our study had three objectives: (1 to analyze the red-crowned crane habitat and its suitability in Cheorwon-gun, using field surveys and habitat modeling; (2 to check the feasibility of alternative habitat patches across demilitarized zones (DMZs; and (3 to propose a conceptual diagram that minimizes habitat loss during development activities. We aim to quantify habitat suitability, the farmland area needed to support existing crane populations in wintertime, disturbance caused by human activities, and vehicular spatial patterns. These data could be used in spatial planning. The framework of this study and the process of making a conceptual diagram could be applied to other areas where there is a conflict between development and habitat conservation.

  18. Microphysical Modelling of the 1999-2000 Arctic Winter. 2; Chlorine Activation and Ozone Depletion

    Science.gov (United States)

    Drdla, K.; Schoeberl, M. R.; Gore, Warren J. (Technical Monitor)

    2001-01-01

    The effect of a range of assumptions about polar stratospheric clouds (PSCs) on ozone depletion has been assessed using at couple microphysical/photochemical model. The composition of the PSCs was varied (ternary solutions, nitric acid trihydrate, nitric acid dehydrate, or ice), as were parameters that affected the levels of denitrification and dehydration. Ozone depletion was affected by assumptions about PSC freezing because of the variability in resultant nitrification chlorine activation in all scenarios was similar despite the range of assumed PSC compositions. Vortex-average ozone loss exceeded 40% in the lower stratosphere for simulations without nitrification an additional ozone loss of 15-20% was possible in scenarios where vortex-average nitrification reached 60%. Ozone loss intensifies non-linearly with enhanced nitrification in air parcels with 90% nitrification 40% ozone loss in mid-April can be attributed to nitrification alone. However, these effects are sensitive to the stability of the vortex in springtime: nitrification only began to influence ozone depletion in mid-March.

  19. STOCHASTIC MODELLING BASED MONTHLY RAINFALL PREDICTION USING SEASONAL ARTIFICIAL NEURAL NETWORKS

    Directory of Open Access Journals (Sweden)

    S.M. Karthik

    2017-01-01

    Full Text Available India is an agrarian society where 13.7% of GDP and 50% of workforce are involved with agriculture. Rainfall plays a vital role in irrigating the land and replenishing the rivers and underground water sources. Therefore the study of rainfall is vital to the economic development and wellbeing of the nation. Accurate prediction of rainfall leads to better agricultural planning, flood prevention and control. The seasonal artificial neural networks can predict monthly rainfall by exploiting the cyclical nature of the weather system. It is dependent on historical time series data and therefore independent of changes in the fundamental models of climate known collectively as manmade climate change. This paper presents the seasonal artificial neural networks applied on the prediction of monthly rainfall. The amounts of rainfall in the twelve months of a year are fed to the neural networks to predict the next twelve months. The gradient descent method is used for training the neural networks. Four performance measures viz. MSE, RMSE, MAD and MAPE are used to assess the system. Experimental results indicate that monthly rainfall patterns can be predicted accurately by seasonal neural networks.

  20. Modelling monthly runoff generation processes following land use changes: groundwater–surface runoff interactions

    Directory of Open Access Journals (Sweden)

    M. Bari

    2004-01-01

    Full Text Available A conceptual water balance model is presented to represent changes in monthly water balance following land use changes. Monthly rainfall–runoff, groundwater and soil moisture data from four experimental catchments in Western Australia have been analysed. Two of these catchments, 'Ernies' (control, fully forested and 'Lemon' (54% cleared are in a zone of mean annual rainfall of 725 mm, while 'Salmon' (control, fully forested and 'Wights' (100% cleared are in a zone with mean annual rainfall of 1125 mm. At the Salmon forested control catchment, streamflow comprises surface runoff, base flow and interflow components. In the Wights catchment, cleared of native forest for pasture development, all three components increased, groundwater levels rose significantly and stream zone saturated area increased from 1% to 15% of the catchment area. It took seven years after clearing for the rainfall–runoff generation process to stabilise in 1984. At the Ernies forested control catchment, the permanent groundwater system is 20 m below the stream bed and so does not contribute to streamflow. Following partial clearing of forest in the Lemon catchment, groundwater rose steadily and reached the stream bed by 1987. The streamflow increased in two phases: (i immediately after clearing due to reduced evapotranspiration, and (ii through an increase in the groundwater-induced stream zone saturated area after 1987. After analysing all the data available, a conceptual monthly model was created, comprising four inter-connecting stores: (i an upper zone unsaturated store, (ii a transient stream zone store, (ii a lower zone unsaturated store and (iv a saturated groundwater store. Data such as rooting depth, Leaf Area Index, soil porosity, profile thickness, depth to groundwater, stream length and surface slope were incorporated into the model as a priori defined attributes. The catchment average values for different stores were determined through matching observed and

  1. Impacts of global warming on Northern Hemisphere winter storm tracks in the CMIP5 model suite

    Science.gov (United States)

    Eichler, Timothy Paul; Gaggini, Natalie; Pan, Zaitao

    2013-05-01

    key question in assessing how global warming may affect climate is how it may impact day-to-day weather. To help answer this question, we evaluate the frequency and intensity of northern hemisphere storm tracks in the National Center for Climate Prediction reanalysis I dataset, and the historical, RCP4.5, and RCP8.5 climate scenarios featured in the CMIP5 simulations. We found that a warmer climate resulted in a general decrease in storm frequency in midlatitudes, especially in RCP8.5. In contrast, frequency trends in the reanalysis data reflected an increase in the North Pacific consistent with a shift towards a positive Pacific Decadal Oscillation and more frequent El Niño events post mid-1970s. An examination of frequency and intensity trends in the active storm track regions of the North Pacific and North Atlantic showed that a significant decrease in storm track frequency was evident for RCP8.5. In contrast, intensity trends were dichotomous, with RCP8.5 exhibiting an increase in intensity in the North Atlantic active storm track region and a decrease in intensity in the North Pacific active storm track region. Poleward of these regions, a significant decrease in storm intensity in the North Atlantic and a significant increase in intensity in the North Pacific in RCP8.5 occurred. We also examined the intensity distribution of storms in the active storm track regions of the North Atlantic and North Pacific and determined that the models produced weaker storms with reduced variability relative to reanalysis data regardless of external climate forcing.

  2. Modelling and forecasting monthly and daily river discharge data using hybrid models and considering autoregressive heteroscedasticity

    Science.gov (United States)

    Szolgayova, Elena

    2010-05-01

    Hybrid modelling, used for simulation and forecasting of hydrological time series, involving both process-based and data-driven types of models combines the available domain knowledge and process physics with the recent advances in data driven tools. In this way, complex hydrological processes can be modelled and forecasted by decomposing the problem into several smaller sub - problems and using process physics based models where these are most appropriate, and data dictated tools (such as ANN, time series models or traditional statistics) for the residual data, when necessary. The fitting and forecasting performance of such models have to be explored case based. So far, only a few attempts to apply various nonlinear time series models within such a framework were reported in the hydrological modelling literature. This contribution presents results concerning the possibility to use GARCH type of models for such purposes. More specifically, error time series from two hydrological conceptual models were analyzed (applied on time series measured from the Hron and Morava Rivers in Slovakia), concentrating on the improvement of the modelling and forecasting performance of these models. The goal of investigation was to try to expand the knowledge in the time series modelling of hydrological model error time series with the aim to test and develop appropriate methods for various time steps from the GARCH family of models. In order to achieve this, following steps were taken: 1. The presence of heteroscedasticity was verified in time series. 2. A model from the GARCH family was fitted on the data, comparing the fit with a fit of an ARMA model. 3. One - step - ahead forecasts from the fitted models were produced, performing comparisons. The investigation of model properties and performances was thoroughly tested under various conditions of their future practical applications. In general, heteroscedasticity was present in the majority of the error time series of the

  3. Effects of climate change on deepwater oxygen and winter mixing in a deep lake (Lake Geneva): Comparing observational findings and modeling

    Science.gov (United States)

    Schwefel, Robert; Gaudard, Adrien; Wüest, Alfred; Bouffard, Damien

    2016-11-01

    Low concentrations of dissolved oxygen remain a global concern regarding the ecological health of lakes and reservoirs. In addition to high nutrient loads, climate-induced changes in lake stratification and mixing represent additional anthropogenic menace resulting in decreased deepwater oxygen levels. The analysis of 43 years of monitoring data from Lake Geneva shows no decreasing trend neither in the areal hypolimnetic mineralization rate nor in the extent of hypoxia. Instead, hypoxic conditions are predominantly controlled by deep mixing in winter and much less by the trophic variations over the past decades. To reproduce winter mixing, the one-dimensional hydrodynamic model SIMSTRAT was specially adapted to deep lakes and run for several climate scenarios. The simulations predicted a decrease in the maximum winter mixing depth from an average of ˜172 m for 1981-2012 to ˜136 m and ˜127 m in response to predicted atmospheric temperatures between 2045-2076 and 2070-2101 according to Intergovernmental Panel on Climate Change scenarios. Concurrently, events with complete homogenization of temperature and oxygen in winter will decrease by ˜50%. Consequently, the hypolimnetic oxygen concentrations will significantly decrease. These results demonstrate that changes in deep mixing can have stronger impact than eutrophication on the deepwater oxygen levels of oligomictic lakes.

  4. Posttreatment motivation and alcohol treatment outcome 9 months later: findings from structural equation modeling.

    Science.gov (United States)

    Cook, Sarah; Heather, Nick; McCambridge, Jim

    2015-02-01

    To investigate the association between posttreatment motivation to change as measured by the Readiness to Change Questionnaire Treatment Version and drinking outcomes 9 months after the conclusion of treatment for alcohol problems. Data from 392 participants in the United Kingdom Alcohol Treatment Trial were used to fit structural equation models investigating relationships between motivation to change pre- and posttreatment and 5 outcomes 9 months later. The models included pathways through changes in drinking behavior during treatment and adjustment for sociodemographic information. Greater posttreatment motivation (being in action vs. preaction) was associated with 3 times higher odds of the most stringent definition of positive outcome (being abstinent or entirely a nonproblem drinker) 9 months later (odds ratio = 3.10, 95% confidence interval [1.83, 5.25]). A smaller indirect effect of pretreatment motivation on this outcome was seen from pathways through drinking behavior during treatment and posttreatment motivation (probit coefficient = 0.08, 95% confidence interval [0.03, 0.14]). A similar pattern of results was seen for other outcomes evaluated. Posttreatment motivation to change has hitherto been little studied and is identified here as a clearly important predictor of longer term treatment outcome. (PsycINFO Database Record (c) 2015 APA, all rights reserved).

  5. Modelling the winter distribution of a rare and endangered migrant, the Aquatic Warbler Acrocephalus paludicola

    DEFF Research Database (Denmark)

    Walther, Bruno A; Schäffer, Norbert; van Niekerk, Adriaan

    2007-01-01

    The Aquatic Warbler Acrocephalus paludicola is one of the most threatened Western Palearctic passerine species, classified as globally Vulnerable. With its breeding grounds relatively secure, a clear need remains for the monitoring and protection of the migration and wintering grounds of this rare...... and endangered migrant. Recent research has shown that the Aquatic Warbler migrates through northwest Africa in autumn and spring. The wintering grounds are apparently limited to wetlands of sub-Saharan West Africa, with records from only about 20 localities in Mauritania, Mali, Senegal and Ghana. Given the lack...

  6. Comparison of Spatial Interpolation and Regression Analysis Models for an Estimation of Monthly Near Surface Air Temperature in China

    Directory of Open Access Journals (Sweden)

    Mengmeng Wang

    2017-12-01

    Full Text Available Near surface air temperature (NSAT is a primary descriptor of terrestrial environmental conditions. In recent decades, many efforts have been made to develop various methods for obtaining spatially continuous NSAT from gauge or station observations. This study compared three spatial interpolation (i.e., Kriging, Spline, and Inversion Distance Weighting (IDW and two regression analysis (i.e., Multiple Linear Regression (MLR and Geographically Weighted Regression (GWR models for predicting monthly minimum, mean, and maximum NSAT in China, a domain with a large area, complex topography, and highly variable station density. This was conducted for a period of 12 months of 2010. The accuracy of the GWR model is better than the MLR model with an improvement of about 3 °C in the Root Mean Squared Error (RMSE, which indicates that the GWR model is more suitable for predicting monthly NSAT than the MLR model over a large scale. For three spatial interpolation models, the RMSEs of the predicted monthly NSAT are greater in the warmer months, and the mean RMSEs of the predicted monthly mean NSAT for 12 months in 2010 are 1.56 °C for the Kriging model, 1.74 °C for the IDW model, and 2.39 °C for the Spline model, respectively. The GWR model is better than the Kriging model in the warmer months, while the Kriging model is superior to the GWR model in the colder months. The total precision of the GWR model is slightly higher than the Kriging model. The assessment result indicated that the higher standard deviation and the lower mean of NSAT from sample data would be associated with a better performance of predicting monthly NSAT using spatial interpolation models.

  7. The U.S. Geological Survey Monthly Water Balance Model Futures Portal

    Science.gov (United States)

    Bock, Andy

    2017-03-16

    Simulations of future climate suggest profiles of temperature and precipitation may differ significantly from those in the past. These changes in climate will likely lead to changes in the hydrologic cycle. As such, natural resource managers are in need of tools that can provide estimates of key components of the hydrologic cycle, uncertainty associated with the estimates, and limitations associated with the climate forcing data used to estimate these components. To help address this need, the U.S. Geological Survey Monthly Water Balance Model Futures Portal (https://my.usgs.gov/mows/) provides a user friendly interface to deliver hydrologic and meteorological variables for monthly historic and potential future climatic conditions across the continental United States.

  8. A modelling study of the latitudinal variations in the nighttime plasma temperatures of the equatorial topside ionosphere during northern winter at solar maximum

    Directory of Open Access Journals (Sweden)

    G. J. Bailey

    2000-11-01

    Full Text Available Latitudinal variations in the nighttime plasma temperatures of the equatorial topside ionosphere during northern winter at solar maximum have been examined by using values modelled by SUPIM (Sheffield University Plasmasphere Ionosphere Model and observations made by the DMSP F10 satellite at 21.00 LT near 800 km altitude. The modelled values confirm that the crests observed near 15° latitude in the winter hemisphere are due to adiabatic heating and the troughs observed near the magnetic equator are due to adiabatic cooling as plasma is transported along the magnetic field lines from the summer hemisphere to the winter hemisphere. The modelled values also confirm that the interhemispheric plasma transport needed to produce the required adiabatic heating/cooling can be induced by F-region neutral winds. It is shown that the longitudinal variations in the observed troughs and crests arise mainly from the longitudinal variations in the magnetic meridional wind. At longitudes where the magnetic declination angle is positive the eastward geographic zonal wind combines with the northward (summer hemisphere to winter hemisphere geographic meridional wind to enhance the northward magnetic meridional wind. This leads to deeper troughs and enhanced crests. At longitudes where the magnetic declination angle is negative the eastward geographic zonal wind opposes the northward geographic meridional wind and the trough depth and crest values are reduced. The characteristic features of the troughs and crests depend, in a complicated manner, on the field-aligned flow of plasma, thermal conduction, and inter-gas heat transfer. At the latitudes of the troughs/crests, the low/high plasma temperatures lead to increased/decreased plasma concentrations.Key words: Ionosphere (equatorial ionosphere; ionosphere-atmosphere interactions

  9. Non-linear modelling of monthly mean vorticity time changes: an application to the western Mediterranean

    Directory of Open Access Journals (Sweden)

    M. Finizio

    Full Text Available Starting from a number of observables in the form of time-series of meteorological elements in various areas of the northern hemisphere, a model capable of fitting past records and predicting monthly vorticity time changes in the western Mediterranean is implemented. A new powerful statistical methodology is introduced (MARS in order to capture the non-linear dynamics of time-series representing the available 40-year history of the hemispheric circulation. The developed model is tested on a suitable independent data set. An ensemble forecast exercise is also carried out to check model stability in reference to the uncertainty of input quantities.

    Key words. Meteorology and atmospheric dynamics · General circulation ocean-atmosphere interactions · Synoptic-scale meteorology

  10. Data from: Modeling winter moth Operophtera brumata egg phenology: nonlinear effects of temperature and developmental stage on developmental rate

    NARCIS (Netherlands)

    Salis, L.; Lof, M.E.; Asch, van M.; Visser, M.E.

    2016-01-01

    Understanding the relationship between an insect's developmental rate and temperature is crucial to forecast insect phenology under climate change. In the winter moth Operophtera brumata timing of egg-hatching has severe fitness consequences on growth and reproduction as egg-hatching has to match

  11. Modeling winter moth Operophtera brumata egg phenology : Nonlinear effects of temperature and developmental stage on developmental rate

    NARCIS (Netherlands)

    Salis, Lucia; Lof, Marjolein; van Asch, Margriet; Visser, Marcel E.

    2016-01-01

    Understanding the relationship between an insect's developmental rate and temperature is crucial to forecast insect phenology under climate change. In the winter moth Operophtera brumata timing of egg-hatching has severe fitness consequences on growth and reproduction as egg-hatching has to match

  12. Global Monthly CO2 Flux Inversion Based on Results of Terrestrial Ecosystem Modeling

    Science.gov (United States)

    Deng, F.; Chen, J.; Peters, W.; Krol, M.

    2008-12-01

    Most of our understanding of the sources and sinks of atmospheric CO2 has come from inverse studies of atmospheric CO2 concentration measurements. However, the number of currently available observation stations and our ability to simulate the diurnal planetary boundary layer evolution over continental regions essentially limit the number of regions that can be reliably inverted globally, especially over continental areas. In order to overcome these restrictions, a nested inverse modeling system was developed based on the Bayesian principle for estimating carbon fluxes of 30 regions in North America and 20 regions for the rest of the globe. Inverse modeling was conducted in monthly steps using CO2 concentration measurements of 5 years (2000 - 2005) with the following two models: (a) An atmospheric transport model (TM5) is used to generate the transport matrix where the diurnal variation n of atmospheric CO2 concentration is considered to enhance the use of the afternoon-hour average CO2 concentration measurements over the continental sites. (b) A process-based terrestrial ecosystem model (BEPS) is used to produce hourly step carbon fluxes, which could minimize the limitation due to our inability to solve the inverse problem in a high resolution, as the background of our inversion. We will present our recent results achieved through a combination of the bottom-up modeling with BEPS and the top-down modeling based on TM5 driven by offline meteorological fields generated by the European Centre for Medium Range Weather Forecast (ECMFW).

  13. Potential Seasonal Predictability for Winter Storms over Europe

    Science.gov (United States)

    Wild, Simon; Befort, Daniel J.; Leckebusch, Gregor C.

    2017-04-01

    Reliable seasonal forecasts of strong extra-tropical cyclones and windstorms would have great social and economical benefits, as these events are the most costly natural hazards over Europe. In a previous study we have shown good agreement of spatial climatological distributions of extra-tropical cyclones and wind storms in state-of-the-art multi-member seasonal prediction systems with reanalysis. We also found significant seasonal prediction skill of extra-tropical cyclones and windstorms affecting numerous European countries. We continue this research by investigating the mechanisms and precursor conditions (primarily over the North Atlantic) on a seasonal time scale leading to enhanced extra-tropical cyclone activity and winter storm frequency over Europe. Our results regarding mechanisms show that an increased surface temperature gradient at the western edge of the North Atlantic can be related to enhanced winter storm frequency further downstream causing for example a greater number of storms over the British Isles, as observed in winter 2013-14.The so-called "Horseshoe Index", a SST tripole anomaly pattern over the North Atlantic in the summer months can also cause a higher number of winter storms over Europe in the subsequent winter. We will show results of AMIP-type sensitivity experiments using an AGCM (ECHAM5), supporting this hypothesis. Finally we will analyse whether existing seasonal forecast systems are able to capture these identified mechanisms and precursor conditions affecting the models' seasonal prediction skill.

  14. Two Monthly Continuous Dynamic Model Based on Nash Bargaining Theory for Conflict Resolution in Reservoir System.

    Directory of Open Access Journals (Sweden)

    Mehran Homayounfar

    Full Text Available So far many optimization models based on Nash Bargaining Theory associated with reservoir operation have been developed. Most of them have aimed to provide practical and efficient solutions for water allocation in order to alleviate conflicts among water users. These models can be discussed from two viewpoints: (i having a discrete nature; and (ii working on an annual basis. Although discrete dynamic game models provide appropriate reservoir operator policies, their discretization of variables increases the run time and causes dimensionality problems. In this study, two monthly based non-discrete optimization models based on the Nash Bargaining Solution are developed for a reservoir system. In the first model, based on constrained state formulation, the first and second moments (mean and variance of the state variable (water level in the reservoir is calculated. Using moment equations as the constraint, the long-term utility of the reservoir manager and water users are optimized. The second model is a dynamic approach structured based on continuous state Markov decision models. The corresponding solution based on the collocation method is structured for a reservoir system. In this model, the reward function is defined based on the Nash Bargaining Solution. Indeed, it is used to yield equilibrium in every proper sub-game, thereby satisfying the Markov perfect equilibrium. Both approaches are applicable for water allocation in arid and semi-arid regions. A case study was carried out at the Zayandeh-Rud river basin located in central Iran to identify the effectiveness of the presented methods. The results are compared with the results of an annual form of dynamic game, a classical stochastic dynamic programming model (e.g. Bayesian Stochastic Dynamic Programming model, BSDP, and a discrete stochastic dynamic game model (PSDNG. By comparing the results of alternative methods, it is shown that both models are capable of tackling conflict issues in

  15. Grid-cell aerosol direct shortwave radiative forcing calculated using the SBDART model with MODIS and AERONET observations: An application in winter and summer in eastern China

    Science.gov (United States)

    Fu, Yunfei; Zhu, Jiachen; Yang, Yuanjian; Yuan, Renmin; Liu, Guosheng; Xian, Tao; Liu, Peng

    2017-08-01

    Taking winter and summer in eastern China as an example application, a grid-cell method of aerosol direct radiative forcing (ADRF) calculation is examined using the Santa Barbara DISORT Atmospheric Radiative Transfer (SBDART) model with inputs from MODIS and AERONET observations and reanalysis data. Results show that there are significant seasonal and regional differences in climatological mean aerosol optical parameters and ADRF. Higher aerosol optical depth (AOD) occurs in summer and two prominent high aerosol loading centers are observed. Higher single scattering albedo (SSA) in summer is likely associated with the weak absorbing secondary aerosols. SSA is higher in North China during summer but higher in South China during winter. Aerosols induce negative forcing at the top of the atmosphere (TOA) and surface during both winter and summer, which may be responsible for the decrease in temperature and the increase in relative humidity. Values of ADRF at the surface are four times stronger than those at the TOA. Both AOD and ADRF present strong interannual variations; however, their amplitudes are larger in summer. Moreover, patterns and trends of ADRF do not always correspond well to those of AOD. Differences in the spatial distributions of ADRF between strong and weak monsoon years are captured effectively. Generally, the present results justify that to calculate grid-cell ADRF at a large scale using the SBDART model with observational aerosol optical properties and reanalysis data is an effective approach.

  16. Arctic sea ice reduction and European cold winters in CMIP5 climate change experiments

    DEFF Research Database (Denmark)

    Yang, Shuting; Christensen, Jens H.

    2012-01-01

    , we find that episodes of cold months will continue to occur and there remains substantial probability for the occurrence of cold winters in Europe linked with sea ice reduction in the Barents and Kara Sea sector. A pattern of cold-European warm-Arctic anomaly is typical for the cold events......European winter climate and its possible relationship with the Arctic sea ice reduction in the recent past and future as simulated by the models of the Climate Model Intercomparison Project phase 5 (CMIP5) is investigated, with focus on the cold winters. While Europe will warm overall in the future...... in the future, which is associated with the negative phase of the Arctic Oscillation. These patterns, however, differ from the corresponding patterns in the historical period, and underline the connection between European cold winter events and Arctic sea ice reduction....

  17. NASA Ocean Biogeochemical Model assimilating satellite chlorophyll data global monthly VR2017 (NOBM_MON) at GES DISC

    Data.gov (United States)

    National Aeronautics and Space Administration — This is the assimilated monthly data from NASA Ocean Biogeochemical Model (NOBM). The NOBM is a comprehensive, interactive ocean biogeochemical model coupled with a...

  18. Winter maintenance performance measure.

    Science.gov (United States)

    2016-01-01

    The Winter Performance Index is a method of quantifying winter storm events and the DOTs response to them. : It is a valuable tool for evaluating the States maintenance practices, performing post-storm analysis, training : maintenance personnel...

  19. Concussion in Winter Sports

    Science.gov (United States)

    ... this? Submit Button Past Emails Concussion in Winter Sports Recommend on Facebook Tweet Share Compartir Get prepared ... to enjoy, practice, and compete in various winter sports. There’s no doubt that these sports are a ...

  20. Assessment of water-limited winter wheat yield potential at spatially contrasting sites in Ireland using a simple growth and development model

    Directory of Open Access Journals (Sweden)

    Lynch J.P.

    2017-09-01

    Full Text Available Although Irish winter wheat yields are among the highest globally, increases in the profitability of this crop are required to maintain its economic viability. However, in order to determine if efforts to further increase Irish wheat yields are likely to be successful, an accurate estimation of the yield potential is required for different regions within Ireland. A winter wheat yield potential model (WWYPM was developed, which estimates the maximum water-limited yield achievable, within the confines of current genetic resources and technologies, using parameters for winter wheat growth and development observed recently in Ireland and a minor amount of daily meteorological input (maximum and minimum daily temperature, total daily rainfall and total daily incident radiation. The WWYPM is composed of three processes: (i an estimation of potential green area index, (ii an estimation of light interception and biomass accumulation and (iii an estimation of biomass partitioning to grain yield. Model validation indicated that WWYPM estimations of water-limited yield potential (YPw were significantly related to maximum yields recorded in variety evaluation trials as well as regional average and maximum farm yields, reflecting the model’s sensitivity to alterations in the climatic environment with spatial and seasonal variations. Simulations of YPw for long-term average weather data at 12 sites located at spatially contrasting regions of Ireland indicated that the typical YPw varied between 15.6 and 17.9 t/ha, with a mean of 16.7 t/ha at 15% moisture content. These results indicate that the majority of sites in Ireland have the potential to grow high-yielding crops of winter wheat when the effects of very high rainfall and other stresses such as disease incidence and nutrient deficits are not considered.

  1. The Turn-of-the-Month-Effect: Evidence from Periodic Generalized Autoregressive Conditional Heteroskedasticity (PGARCH Model

    Directory of Open Access Journals (Sweden)

    Eleftherios Giovanis

    2014-12-01

    Full Text Available The current study examines the turn of the month effect on stock returns in 20 countries. This will allow us to explore whether the seasonal patterns usually found in global data; America, Australia, Europe and Asia. Ordinary Least Squares (OLS is problematic as it leads to unreliable estimations; because of the autocorrelation and Autoregressive Conditional Heteroskedasticity (ARCH effects existence. For this reason Generalized GARCH models are estimated. Two approaches are followed. The first is the symmetric Generalized ARCH (1,1 model. However, previous studies found that volatility tends to increase more when the stock market index decreases than when the stock market index increases by the same amount. In addition there is higher seasonality in volatility rather on average returns. For this reason the Periodic-GARCH (1,1 is estimated. The findings support the persistence of the specific calendar effect in 19 out of 20 countries examined.

  2. Interactions between photoperiodism and temperature with respect to the control of dormancy in the adult stage of Pterostichus oblongopunctatus F. (Col., Carabidae) : II. The development of the reproduction potential during the winter months in the field.

    Science.gov (United States)

    Thiele, H U; Könen, H

    1975-12-01

    The short day effect in gonad maturation (previtellogenesis in the females) of the short day/long day beetle Pterostichus oblongopunctatus depends on an extremely narrow range of temperature (about 10-15°C). This effect was first found in the laboratory. Experiments with beetles captured from the field have demonstrated that they, too, show this dependence. When the short day effects of autumn had acted on the beetles at temperatures around the favourable span, they became fully mature and produced the normal quantity of offspring when brought into the laboratory at long day. These short day maturation effects were diminished in beetles captured during the colder part of the winter from the field; such beetles showed only a small reproduction rate if brought into the long day conditions of the laboratory. Beetles caught during short day at about 10°C in spring again showed the normal reproduction rate in the favourable laboratory conditions. From this, the conclusion is drawn that the short day maturation effect of autumn is diminished in nature by the cold of winter and can be restituted by short day at spring temperatures in a similar manner as was formerly shown by climate simulation experiments in the laboratory (Thiele, 1975).

  3. Intercomparison of prediction skills of ensemble methods using monthly mean temperature simulated by CMIP5 models

    Science.gov (United States)

    Seong, Min-Gyu; Suh, Myoung-Seok; Kim, Chansoo

    2017-08-01

    This study focuses on an objective comparison of eight ensemble methods using the same data, training period, training method, and validation period. The eight ensemble methods are: BMA (Bayesian Model Averaging), HMR (Homogeneous Multiple Regression), EMOS (Ensemble Model Output Statistics), HMR+ with positive coefficients, EMOS+ with positive coefficients, PEA_ROC (Performance-based Ensemble Averaging using ROot mean square error and temporal Correlation coefficient), WEA_Tay (Weighted Ensemble Averaging based on Taylor's skill score), and MME (Multi-Model Ensemble). Forty-five years (1961-2005) of data from 14 CMIP5 models and APHRODITE (Asian Precipitation- Highly-Resolved Observational Data Integration Towards Evaluation of Water Resources) data were used to compare the performance of the eight ensemble methods. Although some models underestimated the variability of monthly mean temperature (MMT), most of the models effectively simulated the spatial distribution of MMT. Regardless of training periods and the number of ensemble members, the prediction skills of BMA and the four multiple linear regressions (MLR) were superior to the other ensemble methods (PEA_ROC, WEA_Tay, MME) in terms of deterministic prediction. In terms of probabilistic prediction, the four MLRs showed better prediction skills than BMA. However, the differences among the four MLRs and BMA were not significant. This resulted from the similarity of BMA weights and regression coefficients. Furthermore, prediction skills of the four MLRs were very similar. Overall, the four MLRs showed the best prediction skills among the eight ensemble methods. However, more comprehensive work is needed to select the best ensemble method among the numerous ensemble methods.

  4. Abnormal storm waves in the winter East/Japan Sea: generation process and hindcasting using an atmosphere-wind wave modelling system

    Directory of Open Access Journals (Sweden)

    H. S. Lee

    2010-04-01

    Full Text Available Abnormal storm waves cause coastal disasters along the coasts of Korean Peninsula and Japan in the East/Japan Sea (EJS in winter, arising due to developed low pressures during the East Asia winter monsoon. The generation of these abnormal storm waves during rough sea states were studied and hindcast using an atmosphere-wave coupled modelling system. Wind waves and swell due to developed low pressures were found to be the main components of abnormal storm waves. The meteorological conditions that generate these waves are classified into three patterns based on past literature that describes historical events as well as on numerical modelling. In hindcasting the abnormal storm waves, a bogussing scheme originally designed to simulate a tropical storm in a mesoscale meteorological model was introduced into the modelling system to enhance the resolution of developed low pressures. The modelling results with a bogussing scheme showed improvements in terms of resolved low pressure, surface wind field, and wave characteristics obtained with the wind field as an input.

  5. Winter wheat yield estimation based on multi-source medium resolution optical and radar imaging data and the AquaCrop model using the particle swarm optimization algorithm

    Science.gov (United States)

    Jin, Xiuliang; Li, Zhenhai; Yang, Guijun; Yang, Hao; Feng, Haikuan; Xu, Xingang; Wang, Jihua; Li, Xinchuan; Luo, Juhua

    2017-04-01

    Timely and accurate estimation of winter wheat yield at a regional scale is crucial for national food policy and security assessments. Near-infrared reflectance is not sensitive to the leaf area index (LAI) and biomass of winter wheat at medium to high canopy cover (CC), and most of the vegetation indices displayed saturation phenomenon. However, LAI and biomass at medium to high CC can be efficiently estimated using imaging data from radar with stronger penetration, such as RADARSAT-2. This study had the following three objectives: (i) to combine vegetation indices based on our previous studies for estimating CC and biomass for winter wheat using HJ-1A/B and RADARSAT-2 imaging data; (ii) to combine HJ-1A/B and RADARSAT-2 imaging data with the AquaCrop model using the particle swarm optimization (PSO) algorithm to estimate winter wheat yield; and (iii) to compare the results from the assimilation of HJ-1A/B + RADARSAT-2 imaging data, HJ-1A/B imaging data, and RADARSAT-2 imaging data into the AquaCrop model using the PSO algorithm. Remote sensing data and concurrent LAI, biomass, and yield of sample fields were acquired in Yangling District, Shaanxi, China, during the 2014 winter wheat growing season. The PSO optimization algorithm was used to integrate the AquaCrop model and remote sensing data for yield estimation. The modified triangular vegetation index 2 (MTVI2) × radar vegetation index (RVI) and the enhanced vegetation index (EVI) × RVI had good relationships with CC and biomass, respectively. The results indicated that the predicted and measured yield (R2 = 0.31 and RMSE = 0.94 ton/ha) had agreement when the estimated CC from the HJ-1A/B and RADARSAT-2 data was used as the dynamic input variable for the AquaCrop model. When the estimated biomass from the HJ-1A/B and RADARSAT-2 data was used as the dynamic input variable for the AquaCrop model, the predicted yield showed agreement with the measured yield (R2 = 0.42 and RMSE = 0.81 ton/ha). These results show

  6. Global characteristics of extreme winters from a multi-millennial simulation

    Energy Technology Data Exchange (ETDEWEB)

    Hunt, B.G. [CSIRO Marine and Atmospheric Research, PO Box 1, Aspendale (Australia)

    2011-10-15

    Output from a multi-millennial simulation with the CSIRO Mark 2 coupled global climatic model has been analysed to determine the principal characteristics of extreme winters over the globe for ''present conditions''. Thus, this study is not concerned with possible changes in winter conditions associated with anthropogenically induced climatic change. Defining an extreme winter as having a surface temperature anomaly of below -2 standard deviations (sd) revealed a general occurrence rate over the globe of between 100 and 200 over a 6,000-year period of the simulation, with somewhat higher values over northwest North America. For temperature anomalies below -3 sd the corresponding occurrence rate drops to about 10. Spatial correlation studies revealed that extreme winters over regions in Europe, North America or Asia were very limited geographically, with time series of the surface temperature anomalies for these regions having mutual correlation coefficients of about 0.2. The temporal occurrence rates of winters (summers) having sd below -3 (above +3) were very asymmetric and sporadic, suggesting that such events arise from stochastic influences. Multi-year sequences of extreme winters were comparatively rare events. Detailed analysis revealed that the temporal and spatial evolution of the monthly surface temperature anomalies associated with an individual extreme winter were well replicated in the simulation, as were daily time series of such anomalies. Apart from an influence of the North Atlantic Oscillation on extreme winters in Europe, other prominent climatic oscillations were very poorly correlated with such winters. Rather modest winter temperature anomalies were found in the southern hemisphere. (orig.)

  7. Winter swimming improves general well-being.

    Science.gov (United States)

    Huttunen, Pirkko; Kokko, Leena; Ylijukuri, Virpi

    2004-05-01

    This study deals with the effects of regular winter swimming on the mood of the swimmers. Profile of Mood State (POMS) and OIRE questionnaires were completed before (October) and after (January) the four-month winter swimming period. In the beginning, there were no significant differences in the mood states and subjective feelings between the swimmers and the controls. The swimmers had more diseases (about 50%) diagnosed by a physician. Tension, fatigue, memory and mood negative state points in the swimmers significantly decreased with the duration of the swimming period. After four months, the swimmers felt themselves to be more energetic, active and brisk than the controls. Vigour-activity scores were significantly greater (p winter swimming had relieved pains. Improvement of general well-being is thus a benefit induced by regular winter swimming.

  8. Transfer function modeling of the monthly accumulated rainfall series over the Iberian Peninsula

    Energy Technology Data Exchange (ETDEWEB)

    Mateos, Vidal L.; Garcia, Jose A.; Serrano, Antonio; De la Cruz Gallego, Maria [Departamento de Fisica, Universidad de Extremadura, Badajoz (Spain)

    2002-10-01

    In order to improve the results given by Autoregressive Moving-Average (ARMA) modeling for the monthly accumulated rainfall series taken at 19 observatories of the Iberian Peninsula, a Discrete Linear Transfer Function Noise (DLTFN) model was applied taking the local pressure series (LP), North Atlantic sea level pressure series (SLP) and North Atlantic sea surface temperature (SST) as input variables, and the rainfall series as the output series. In all cases, the performance of the DLTFN models, measured by the explained variance of the rainfall series, is better than the performance given by the ARMA modeling. The best performance is given by the models that take the local pressure as the input variable, followed by the sea level pressure models and the sea surface temperature models. Geographically speaking, the models fitted to those observatories located in the west of the Iberian Peninsula work better than those on the north and east of the Peninsula. Also, it was found that there is a region located between 0 N and 20 N, which shows the highest cross-correlation between SST and the peninsula rainfalls. This region moves to the west and northwest off the Peninsula when the SLP series are used. [Spanish] Con el objeto de mejorar los resultados porporcionados por los modelos Autorregresivo Media Movil (ARMA) ajustados a las precipitaciones mensuales acumuladas registradas en 19 observatorios de la Peninsula Iberica se han usado modelos de funcion de transferencia (DLTFN) en los que se han empleado como variable independiente la presion local (LP), la presion a nivel del mar (SLP) o la temperatura de agua del mar (SST) en el Atlantico Norte. En todos los casos analizados, los resultados obtenidos con los modelos DLTFN, medidos mediante la varianza explicada por el modelo, han sido mejores que los resultados proporcionados por los modelos ARMA. Los mejores resultados han sido dados por aquellos modelos que usan la presion local como variable de entrada, seguidos

  9. Winter Storm Zones on Mars

    Science.gov (United States)

    Hollingsworth, J. L.; Haberle, R. M.; Barnes, J. R.; Bridger, A. F. C.; Cuzzi, Jeffrey N. (Technical Monitor)

    1995-01-01

    Preferred regions of weather activity in Mars' winter middle latitudes-so called 'storm zones' are found in a general circulation model of Mars' atmospheric circulation. During northern winter, these storm zones occur in middle latitudes in the major planitia (low-relief regions) of the western and eastern hemisphere. In contrast, the highlands of the eastern hemisphere are mostly quiescent. Compared to Earth's storm zones where diabatic heating associated with land-sea thermal contrasts is crucial, orography on Mars is fundamental to the regionalization of weather activity. Future spacecraft missions aimed at assessing Mars' climate and its variability need to include such regions in observation strategies.

  10. Modeling of Monthly Residential and Commercial Electricity Consumption Using Nonlinear Seasonal Models—The Case of Hong Kong

    Directory of Open Access Journals (Sweden)

    Wai-Ming To

    2017-06-01

    Full Text Available Accurate modeling and forecasting monthly electricity consumption are the keys to optimizing energy management and planning. This paper examines the seasonal characteristics of electricity consumption in Hong Kong—a subtropical city with 7 million people. Using the data from January 1970 to December 2014, two novel nonlinear seasonal models for electricity consumption in the residential and commercial sectors were obtained. The models show that the city’s monthly residential and commercial electricity consumption patterns have different seasonal variations. Specifically, monthly residential electricity consumption (mainly for appliances and cooling in summer has a quadratic relationship with monthly mean air temperature, while monthly commercial electricity consumption has a linear relationship with monthly mean air temperature. The nonlinear seasonal models were used to predict residential and commercial electricity consumption for the period January 2015–December 2016. The correlations between the predicted and actual values were 0.976 for residential electricity consumption and 0.962 for commercial electricity consumption, respectively. The root mean square percentage errors for the predicted monthly residential and commercial electricity consumption were 7.0% and 6.5%, respectively. The new nonlinear seasonal models can be applied to other subtropical urban areas, and recommendations on the reduction of commercial electricity consumption are given.

  11. NLDAS Mosaic Land Surface Model L4 Monthly Climatology 0.125 x 0.125 degree V002

    Data.gov (United States)

    National Aeronautics and Space Administration — This monthly climatology data set contains a series of land surface parameters simulated from the Mosaic land-surface model (LSM) for Phase 2 of the North American...

  12. Monthly urban (municipal and industrial use) pumpage for the Central Valley Hydrologic Model (CVHM) by Water Balance Subregion (WBS)

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — This digital dataset contains the monthly urban (municipal and industrial use) pumpage for the Central Valley Hydrologic Model (CVHM) by Water Balance Subregion...

  13. Monthly and Fortnightly Tidal Variations of the Earth's Rotation Rate Predicted by a TOPEX/POSEIDON Empirical Ocean Tide Model

    Science.gov (United States)

    Desai, S.; Wahr, J.

    1998-01-01

    Empirical models of the two largest constituents of the long-period ocean tides, the monthly and the fortnightly constituents, are estimated from repeat cycles 10 to 210 of the TOPEX/POSEIDON (T/P) mission.

  14. Output fields from the NOAA WAVEWATCH III® wave model monthly hindcasts for 2011-07 (NODC Accession 0089885)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The NOAA WAVEWATCH III® hindcast dataset comprises output fields from the monthly WAVEWATCH III® hindcast model runs conducted at the National Centers for...

  15. Output fields from the NOAA WAVEWATCH III® wave model monthly hindcasts for 2009-01 (NODC Accession 0089855)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The NOAA WAVEWATCH III® hindcast dataset comprises output fields from the monthly WAVEWATCH III® hindcast model runs conducted at the National Centers for...

  16. Output fields from the NOAA WAVEWATCH III® wave model monthly hindcasts for 2006-02 (NODC Accession 0089820)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The NOAA WAVEWATCH III® hindcast dataset comprises output fields from the monthly WAVEWATCH III® hindcast model runs conducted at the National Centers for...

  17. Output fields from the NOAA WAVEWATCH III® wave model monthly hindcasts for 2005-08 (NODC Accession 0089814)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The NOAA WAVEWATCH III® hindcast dataset comprises output fields from the monthly WAVEWATCH III® hindcast model runs conducted at the National Centers for...

  18. Output fields from the NOAA WAVEWATCH III® wave model monthly hindcasts for 2013-06 (NODC Accession 0110318)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The NOAA WAVEWATCH III® hindcast dataset comprises output fields from the monthly WAVEWATCH III® hindcast model runs conducted at the National Centers for...

  19. Output fields from the NOAA WAVEWATCH III® wave model monthly hindcasts for 2007-04 (NODC Accession 0089834)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The NOAA WAVEWATCH III® hindcast dataset comprises output fields from the monthly WAVEWATCH III® hindcast model runs conducted at the National Centers for...

  20. Output fields from the NOAA WAVEWATCH III® wave model monthly hindcasts for 2010-03 (NODC Accession 0089869)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The NOAA WAVEWATCH III® hindcast dataset comprises output fields from the monthly WAVEWATCH III® hindcast model runs conducted at the National Centers for...

  1. Output fields from the NOAA WAVEWATCH III® wave model monthly hindcasts for 2008-03 (NODC Accession 0089845)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The NOAA WAVEWATCH III® hindcast dataset comprises output fields from the monthly WAVEWATCH III® hindcast model runs conducted at the National Centers for...

  2. Output fields from the NOAA WAVEWATCH III® wave model monthly hindcasts for 2008-08 (NODC Accession 0089850)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The NOAA WAVEWATCH III® hindcast dataset comprises output fields from the monthly WAVEWATCH III® hindcast model runs conducted at the National Centers for...

  3. Output fields from the NOAA WAVEWATCH III® wave model monthly hindcasts for 2012-08 (NODC Accession 0098973)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The NOAA WAVEWATCH III® hindcast dataset comprises output fields from the monthly WAVEWATCH III® hindcast model runs conducted at the National Centers for...

  4. Output fields from the NOAA WAVEWATCH III® wave model monthly hindcasts for 2007-06 (NODC Accession 0089836)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The NOAA WAVEWATCH III® hindcast dataset comprises output fields from the monthly WAVEWATCH III® hindcast model runs conducted at the National Centers for...

  5. NLDAS Noah Land Surface Model L4 Monthly Climatology 0.125 x 0.125 degree V002

    Data.gov (United States)

    National Aeronautics and Space Administration — This monthly climatology data set contains a series of land surface parameters simulated from the Noah land-surface model (LSM) for Phase 2 of the North American...

  6. Output fields from the NOAA WAVEWATCH III® wave model monthly hindcasts for 2012-12 (NODC Accession 0104257)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The NOAA WAVEWATCH III® hindcast dataset comprises output fields from the monthly WAVEWATCH III® hindcast model runs conducted at the National Centers for...

  7. Output fields from the NOAA WAVEWATCH III® wave model monthly hindcasts for 2009-05 (NODC Accession 0089859)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The NOAA WAVEWATCH III® hindcast dataset comprises output fields from the monthly WAVEWATCH III® hindcast model runs conducted at the National Centers for...

  8. Output fields from the NOAA WAVEWATCH III® wave model monthly hindcasts for 2014-10 (NODC Accession 0126373)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The NOAA WAVEWATCH III® hindcast dataset comprises output fields from the monthly WAVEWATCH III® hindcast model runs conducted at the National Centers for...

  9. Output fields from the NOAA WAVEWATCH III® wave model monthly hindcasts for 2007-12 (NODC Accession 0089842)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The NOAA WAVEWATCH III® hindcast dataset comprises output fields from the monthly WAVEWATCH III® hindcast model runs conducted at the National Centers for...

  10. Output fields from the NOAA WAVEWATCH III® wave model monthly hindcasts for 2014-09 (NODC Accession 0125935)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The NOAA WAVEWATCH III® hindcast dataset comprises output fields from the monthly WAVEWATCH III® hindcast model runs conducted at the National Centers for...

  11. Output fields from the NOAA WAVEWATCH III® wave model monthly hindcasts for 2014-01 (NODC Accession 0117477)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The NOAA WAVEWATCH III® hindcast dataset comprises output fields from the monthly WAVEWATCH III® hindcast model runs conducted at the National Centers for...

  12. Output fields from the NOAA WAVEWATCH III® wave model monthly hindcasts for 2012-10 (NODC Accession 0104207)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The NOAA WAVEWATCH III® hindcast dataset comprises output fields from the monthly WAVEWATCH III® hindcast model runs conducted at the National Centers for...

  13. Output fields from the NOAA WAVEWATCH III® wave model monthly hindcasts for 2006-08 (NODC Accession 0089826)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The NOAA WAVEWATCH III® hindcast dataset comprises output fields from the monthly WAVEWATCH III® hindcast model runs conducted at the National Centers for...

  14. Output fields from the NOAA WAVEWATCH III® wave model monthly hindcasts for 2010-10 (NODC Accession 0089876)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The NOAA WAVEWATCH III® hindcast dataset comprises output fields from the monthly WAVEWATCH III® hindcast model runs conducted at the National Centers for...

  15. Output fields from the NOAA WAVEWATCH III® wave model monthly hindcasts for 2010-12 (NODC Accession 0089878)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The NOAA WAVEWATCH III® hindcast dataset comprises output fields from the monthly WAVEWATCH III® hindcast model runs conducted at the National Centers for...

  16. Output fields from the NOAA WAVEWATCH III® wave model monthly hindcasts for 2006-12 (NODC Accession 0089830)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The NOAA WAVEWATCH III® hindcast dataset comprises output fields from the monthly WAVEWATCH III® hindcast model runs conducted at the National Centers for...

  17. Output fields from the NOAA WAVEWATCH III® wave model monthly hindcasts for 2009-07 (NODC Accession 0089861)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The NOAA WAVEWATCH III® hindcast dataset comprises output fields from the monthly WAVEWATCH III® hindcast model runs conducted at the National Centers for...

  18. Output fields from the NOAA WAVEWATCH III® wave model monthly hindcasts for 2014-11 (NODC Accession 0126391)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The NOAA WAVEWATCH III® hindcast dataset comprises output fields from the monthly WAVEWATCH III® hindcast model runs conducted at the National Centers for...

  19. Output fields from the NOAA WAVEWATCH III® wave model monthly hindcasts for 2009-12 (NODC Accession 0089866)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The NOAA WAVEWATCH III® hindcast dataset comprises output fields from the monthly WAVEWATCH III® hindcast model runs conducted at the National Centers for...

  20. Output fields from the NOAA WAVEWATCH III® wave model monthly hindcasts for 2013-10 (NODC Accession 0115066)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The NOAA WAVEWATCH III® hindcast dataset comprises output fields from the monthly WAVEWATCH III® hindcast model runs conducted at the National Centers for...

  1. Output fields from the NOAA WAVEWATCH III® wave model monthly hindcasts for 2015-07 (NCEI Accession 0130763)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The NOAA WAVEWATCH III® hindcast dataset comprises output fields from the monthly WAVEWATCH III® hindcast model runs conducted at the National Centers for...

  2. Output fields from the NOAA WAVEWATCH III® wave model monthly hindcasts for 2013-07 (NODC Accession 0114816)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The NOAA WAVEWATCH III® hindcast dataset comprises output fields from the monthly WAVEWATCH III® hindcast model runs conducted at the National Centers for...

  3. Output fields from the NOAA WAVEWATCH III® wave model monthly hindcasts for 2012-05 (NODC Accession 0098970)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The NOAA WAVEWATCH III® hindcast dataset comprises output fields from the monthly WAVEWATCH III® hindcast model runs conducted at the National Centers for...

  4. Output fields from the NOAA WAVEWATCH III® wave model monthly hindcasts for 2008-06 (NODC Accession 0089848)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The NOAA WAVEWATCH III® hindcast dataset comprises output fields from the monthly WAVEWATCH III® hindcast model runs conducted at the National Centers for...

  5. Output fields from the NOAA WAVEWATCH III® wave model monthly hindcasts for 2007-09 (NODC Accession 0089839)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The NOAA WAVEWATCH III® hindcast dataset comprises output fields from the monthly WAVEWATCH III® hindcast model runs conducted at the National Centers for...

  6. Output fields from the NOAA WAVEWATCH III® wave model monthly hindcasts for 2011-05 (NODC Accession 0089883)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The NOAA WAVEWATCH III® hindcast dataset comprises output fields from the monthly WAVEWATCH III® hindcast model runs conducted at the National Centers for...

  7. Output fields from the NOAA WAVEWATCH III® wave model monthly hindcasts for 2008-09 (NODC Accession 0089851)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The NOAA WAVEWATCH III® hindcast dataset comprises output fields from the monthly WAVEWATCH III® hindcast model runs conducted at the National Centers for...

  8. Output fields from the NOAA WAVEWATCH III® wave model monthly hindcasts for 2009-09 (NODC Accession 0089863)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The NOAA WAVEWATCH III® hindcast dataset comprises output fields from the monthly WAVEWATCH III® hindcast model runs conducted at the National Centers for...

  9. Output fields from the NOAA WAVEWATCH III® wave model monthly hindcasts for 2011-01 (NODC Accession 0089879)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The NOAA WAVEWATCH III® hindcast dataset comprises output fields from the monthly WAVEWATCH III® hindcast model runs conducted at the National Centers for...

  10. Output fields from the NOAA WAVEWATCH III® wave model monthly hindcasts for 2006-07 (NODC Accession 0089825)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The NOAA WAVEWATCH III® hindcast dataset comprises output fields from the monthly WAVEWATCH III® hindcast model runs conducted at the National Centers for...

  11. Output fields from the NOAA WAVEWATCH III® wave model monthly hindcasts for 2012-02 (NODC Accession 0089892)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The NOAA WAVEWATCH III® hindcast dataset comprises output fields from the monthly WAVEWATCH III® hindcast model runs conducted at the National Centers for...

  12. DEVELOPING MODELS TO PREDICT STUNTING AMONG 6-59 MONTHS CHILDREN IN A SLUM OF KOLKATA

    Directory of Open Access Journals (Sweden)

    Ranadip Chowdhury

    2013-12-01

    Full Text Available Background: India is one among the many countries where child malnutrition is severe and is a major underlying cause of child mortality.  48 per cent of under five children in India are stunted and India accounts for more than 3 out of every 10 stunted children in the world. Even after implementation of the national nutritional programmes the magnitude of the problem remains at large, this necessitates a detailed analysis regarding the factors leading to stunting and to identify which group of factors to target first to make a significant effect.Methods: This  Community  based  cross-sectional  study was done  in  the service area of  Urban  Training  Centre  in  Baghbazar,  Kolkata  with  84  children  aged  6-59  months. Anthropometric measurements of the study population were done  using  standard methods and information regarding risk factors were collected from their parents using a pre-designed questionnaire. WHO Anthro for personal computers version3.2.2 (Z score and SPSS version16.0 was used to analyse the data (multivariate logistic regression and ROC curve.  Results: The study indicates a 26.2% prevalence of stunting among the study population. To observe the risk factors for stunting two models were compared by creating ROC curves, a socio demographic factor model which explained 70% of the stunting in the population in comparison to the second model regarding the factors related to birth and feeding practices which explained 65%. Conclusion: The current study further emphasizes the need to implement relevant interventions to combat malnutrition in this region and other similar settings.

  13. Modeling precipitation use efficiency of winter wheat using climatic parameters, soil properties and topographic indices in a semiarid region, Khodabandeh County, Iran

    Science.gov (United States)

    Babaei, Fatemeh; Vaezi, AliReza; Taheri, Mehdi; Zarrinabadi, Ehsan

    2017-04-01

    Improved understanding of the impact of crucial factors affecting on rainfed wheat precipitation use efficiency (PUE), is needed to cope with increasing demands for sustainable agriculture in semiarid regions. The present research has assessed the effects of climatic parameters, soil physiochemical characteristics and topographic indices on wheat gain yield (WGY), PUE and effective precipitation use efficiency (PUEe) of rainfed winter wheat in a research over rainfed wheat croplands of Khodabandeh County. Therefore, 289 soil samples were collected from rainfed winter wheat croplands in two replicates, totally 578 soil samples, within the county of Khodanbandeh, in (2013-2014). Also, the WGY was measured in each cropland that year. Environmental variables including some soil physiochemical characteristics, topographic indices derived from digital terrain analysis and climatic parameters including growth season precipitation and air temperature were analyzed to develop a proper model to represent WGY, PUE and PUEe. Similar to the first study, the data was divided into two dataset: model (n=238) and test dataset (n=60) and the decision tree was used to develop the best suitable model to describe WGY, PUE and PUEe. The results indicated that CK using slope as auxiliary variable played as the best model to describe the spatial variation of WGY (n=60, R2=0.92, RMSE= 77.78 kg ha-1). Although, MLR combining principal component analysis (PCA) was able to describe PUE significantly (n=238, R2=0.28, P 1.34 kg ha-1 mm-1). Similarly, PUEe was modeled significantly (n=238, R2=0.25, Pproperties in PUE determination. Among all models Kr and CK performed better than other spatial interpolation models. In order to the lacking of reliable climatic data especially in small scales, and complexity of effective parameters, accurate spatially modelling of PUE and PUEe appears difficult.

  14. Winters fuels report

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1995-10-27

    The outlook for distillate fuel oil this winter is for increased demand and a return to normal inventory patterns, assuming a resumption of normal, cooler weather than last winter. With industrial production expected to grow slightly from last winter`s pace, overall consumption is projected to increase 3 percent from last winter, to 3.4 million barrels per day during the heating season (October 1, 1995-March 31, 1996). Much of the supply win come from stock drawdowns and refinery production. Estimates for the winter are from the Energy Information Administration`s (EIA) 4th Quarter 1995 Short-Tenn Energy Outlook (STEO) Mid-World Oil Price Case forecast. Inventories in place on September 30, 1995, of 132 million barrels were 9 percent below the unusually high year-earlier level. Inventories of high-sulfur distillate fuel oil, the principal type used for heating, were 13 percent lower than a year earlier. Supply problems are not anticipated because refinery production and the ready availability of imports should be adequate to meet demand. Residential heating off prices are expected to be somewhat higher than last winter`s, as the effects of lower crude oil prices are offset by lower distillate inventories. Heating oil is forecast to average $0.92 per gallon, the highest price since the winter of 1992-93. Diesel fuel (including tax) is predicted to be slightly higher than last year at $1.13 per gallon. This article focuses on the winter assessment for distillate fuel oil, how well last year`s STEO winter outlook compared to actual events, and expectations for the coming winter. Additional analyses include regional low-sulfur and high-sulfur distillate supply, demand, and prices, and recent trends in distillate fuel oil inventories.

  15. Source-sector contributions to European ozone and fine PM in 2010 using AQMEII modeling data

    National Research Council Canada - National Science Library

    Prakash Karamchandani; Yoann Long; Guido Pirovano; Alessandra Balzarini; Greg Yarwood

    2017-01-01

    ...), which track source contributions. We present results from a CAMx source attribution modeling study for a summer month and a winter month using a recently evaluated European CAMx modeling database developed for Phase 3 of the Air...

  16. Monthly water balance model for climate change analysis in agriculture with R

    Science.gov (United States)

    Kalicz, Péter; Herceg, András; Gribovszki, Zoltán

    2015-04-01

    For Hungary regional climate models projections suggest a warmer climate and some changes in annual precipitation distribution. These changes force the whole agrarian sector to consider the traditional cropping technologies. This situation is more serious in forestry because some forest populations are on their xeric distributional limits (Gálos et. al, 2014). Additionally, a decision has an impact sometimes longer than one hundred years. To support the stakeholder there is a project which develops a GIS (Geographic Information System) based decision support system. Hydrology plays significant role in this system because water is often one of the most important limiting factor in Hungary. A modified Thorntwaite-type monthly water balance model was choosen to produce hydrological estimations for the GIS modules. This model is calibrated with the available data between 2000 and 2008. Beside other meteorological data we used mainly an actual evapotranspiration map in the calibration phase, which was derived with the Complementary-relationship-based evapotranspiration mapping (CREMAP; Szilágyi and Kovács, 2011) technique. The calibration process is pixel based and it has several stochastic steps. We try to find a flexible solution for the model implementation which easy to automatize and can be integrate in GIS systems. The open source R programming language was selected which well satisfied these demands. The result of this development is summarized as an R package. This publication has been supported by AGRARKLIMA.2 VKSZ_12-1-2013-0034 project. References Gálos B., Antal V., Czimber K., Mátyás Cs. (2014) Forest ecosystems, sewage works and droughts - possibilities for climate change adaptation. In: Santamarta J.C., Hernandez-Gutiérrez L.E., Arraiza M.P. (eds) 2014. Natural Hazards and Climate Change/Riesgos Naturales y Cambio Climático. Madrid: Colegio de Ingenieros de Montes. ISBN 978-84-617-1060-7, D.L. TF 565-2014, 91-104 pp Szilágyi J., Kovács Á. (2011

  17. Mapping monthly rainfall erosivity in Europe.

    Science.gov (United States)

    Ballabio, Cristiano; Borrelli, Pasquale; Spinoni, Jonathan; Meusburger, Katrin; Michaelides, Silas; Beguería, Santiago; Klik, Andreas; Petan, Sašo; Janeček, Miloslav; Olsen, Preben; Aalto, Juha; Lakatos, Mónika; Rymszewicz, Anna; Dumitrescu, Alexandru; Tadić, Melita Perčec; Diodato, Nazzareno; Kostalova, Julia; Rousseva, Svetla; Banasik, Kazimierz; Alewell, Christine; Panagos, Panos

    2017-02-01

    Rainfall erosivity as a dynamic factor of soil loss by water erosion is modelled intra-annually for the first time at European scale. The development of Rainfall Erosivity Database at European Scale (REDES) and its 2015 update with the extension to monthly component allowed to develop monthly and seasonal R-factor maps and assess rainfall erosivity both spatially and temporally. During winter months, significant rainfall erosivity is present only in part of the Mediterranean countries. A sudden increase of erosivity occurs in major part of European Union (except Mediterranean basin, western part of Britain and Ireland) in May and the highest values are registered during summer months. Starting from September, R-factor has a decreasing trend. The mean rainfall erosivity in summer is almost 4 times higher (315MJmmha-1h-1) compared to winter (87MJmmha-1h-1). The Cubist model has been selected among various statistical models to perform the spatial interpolation due to its excellent performance, ability to model non-linearity and interpretability. The monthly prediction is an order more difficult than the annual one as it is limited by the number of covariates and, for consistency, the sum of all months has to be close to annual erosivity. The performance of the Cubist models proved to be generally high, resulting in R2 values between 0.40 and 0.64 in cross-validation. The obtained months show an increasing trend of erosivity occurring from winter to summer starting from western to Eastern Europe. The maps also show a clear delineation of areas with different erosivity seasonal patterns, whose spatial outline was evidenced by cluster analysis. The monthly erosivity maps can be used to develop composite indicators that map both intra-annual variability and concentration of erosive events. Consequently, spatio-temporal mapping of rainfall erosivity permits to identify the months and the areas with highest risk of soil loss where conservation measures should be applied in

  18. Modelling effects of chemical exposure on birds wintering in agricultural landscapes: The western burrowing owl (Athene cunicularia hypugaea) as a case study

    Science.gov (United States)

    Engelman, Catherine A.; Grant, William E.; Mora, Miguel A.; Woodin, Marc

    2012-01-01

    We describe an ecotoxicological model that simulates the sublethal and lethal effects of chronic, low-level, chemical exposure on birds wintering in agricultural landscapes. Previous models estimating the impact on wildlife of chemicals used in agro-ecosystems typically have not included the variety of pathways, including both dermal and oral, by which individuals are exposed. The present model contains four submodels simulating (1) foraging behavior of individual birds, (2) chemical applications to crops, (3) transfers of chemicals among soil, insects, and small mammals, and (4) transfers of chemicals to birds via ingestion and dermal exposure. We demonstrate use of the model by simulating the impacts of a variety of commonly used herbicides, insecticides, growth regulators, and defoliants on western burrowing owls (Athene cunicularia hypugaea) that winter in agricultural landscapes in southern Texas, United States. The model generated reasonable movement patterns for each chemical through soil, water, insects, and rodents, as well as into the owl via consumption and dermal absorption. Sensitivity analysis suggested model predictions were sensitive to uncertainty associated with estimates of chemical half-lives in birds, soil, and prey, sensitive to parameters associated with estimating dermal exposure, and relatively insensitive to uncertainty associated with details of chemical application procedures (timing of application, amount of drift). Nonetheless, the general trends in chemical accumulations and the relative impacts of the various chemicals were robust to these parameter changes. Simulation results suggested that insecticides posed a greater potential risk to owls of both sublethal and lethal effects than do herbicides, defoliants, and growth regulators under crop scenarios typical of southern Texas, and that use of multiple indicators, or endpoints provided a more accurate assessment of risk due to agricultural chemical exposure. The model should prove

  19. Parameter regionalization of a monthly water balance model for the conterminous United States

    Science.gov (United States)

    Bock, Andrew R.; Hay, Lauren E.; McCabe, Gregory J.; Markstrom, Steven L.; Atkinson, R. Dwight

    2016-01-01

    A parameter regionalization scheme to transfer parameter values from gaged to ungaged areas for a monthly water balance model (MWBM) was developed and tested for the conterminous United States (CONUS). The Fourier Amplitude Sensitivity Test, a global-sensitivity algorithm, was implemented on a MWBM to generate parameter sensitivities on a set of 109 951 hydrologic response units (HRUs) across the CONUS. The HRUs were grouped into 110 calibration regions based on similar parameter sensitivities. Subsequently, measured runoff from 1575 streamgages within the calibration regions were used to calibrate the MWBM parameters to produce parameter sets for each calibration region. Measured and simulated runoff at the 1575 streamgages showed good correspondence for the majority of the CONUS, with a median computed Nash–Sutcliffe efficiency coefficient of 0.76 over all streamgages. These methods maximize the use of available runoff information, resulting in a calibrated CONUS-wide application of the MWBM suitable for providing estimates of water availability at the HRU resolution for both gaged and ungaged areas of the CONUS.

  20. Comprehensive modeling of monthly mean soil temperature using multivariate adaptive regression splines and support vector machine

    Science.gov (United States)

    Mehdizadeh, Saeid; Behmanesh, Javad; Khalili, Keivan

    2017-07-01

    Soil temperature (T s) and its thermal regime are the most important factors in plant growth, biological activities, and water movement in soil. Due to scarcity of the T s data, estimation of soil temperature is an important issue in different fields of sciences. The main objective of the present study is to investigate the accuracy of multivariate adaptive regression splines (MARS) and support vector machine (SVM) methods for estimating the T s. For this aim, the monthly mean data of the T s (at depths of 5, 10, 50, and 100 cm) and meteorological parameters of 30 synoptic stations in Iran were utilized. To develop the MARS and SVM models, various combinations of minimum, maximum, and mean air temperatures (T min, T max, T); actual and maximum possible sunshine duration; sunshine duration ratio (n, N, n/N); actual, net, and extraterrestrial solar radiation data (R s, R n, R a); precipitation (P); relative humidity (RH); wind speed at 2 m height (u 2); and water vapor pressure (Vp) were used as input variables. Three error statistics including root-mean-square-error (RMSE), mean absolute error (MAE), and determination coefficient (R 2) were used to check the performance of MARS and SVM models. The results indicated that the MARS was superior to the SVM at different depths. In the test and validation phases, the most accurate estimations for the MARS were obtained at the depth of 10 cm for T max, T min, T inputs (RMSE = 0.71 °C, MAE = 0.54 °C, and R 2 = 0.995) and for RH, V p, P, and u 2 inputs (RMSE = 0.80 °C, MAE = 0.61 °C, and R 2 = 0.996), respectively.

  1. Comparison of GPS-TEC variation during quiet and disturbed period using the Holt-Winter method and IRI-2012 model over Malaysia

    Science.gov (United States)

    Ahmed Ismail, Nouf Abd Emunim; Abdullah, Mardina; Hasbi, Alina Marie

    2016-07-01

    Total Electron Content (TEC) is the main parameter in the ionosphere that has significant effects on radio wave; it changes the speed and direction of the signal propagation, causing the delay of the Global Positioning System (GPS) signals. Therefore, it is crucial to validate the performance of the ionospheric model to reveal the variety of ionospheric behaviour during quiet and disturbed period. This research presents the performance evaluation of the statistical Holt-Winter method and IRI-2012 model using three topside electron density options: IRI-2001, IRI01-corr and NeQuick with the observed GPS-TEC during quiet and disturbed period. The GPS-TEC data were derived from the dual frequency GPS receiver at JUPEM (Department of Survey and Mapping Malaysia), from the UUMK station (north Peninsular Malaysia) at geographic coordinates of 6.46°N-100.50°E and geomagnetic coordinates of 3.32°S-172.99°E and TGPG station (south Peninsular Malaysia) at geographic coordinates of 1.36°N-104.10°E and geomagnetic coordinates of 8.43°S -176.53°E, during March of 2013. The maximum value of the GPS-TEC was at the post noon time at 17:00 LT and the minimum was in the early morning from 6:00-7:00 LT. During the quiet period, the maximum GPS-TEC at the UUMK station was 52 TECU while at the TGPG station, it was 60 TECU. During the disturbed period, when intense geomagnetic storm occurred on 17 March 2013, the maximum GPS-TEC recorded was 58 TECU and 65 TECU in UUMK and TGPG station, respectively. The diurnal hourly variation during the quiet period indicated that IRI-2001, IRI01-corr, and NeQuick had overestimation agreement during the day hours except for the time between 11:00-19:00 LT when IRI01-corr and NeQuick showed underestimation, while during 13:00-20:00 LT, IRI-2001 showed slight underestimation whereas the Holt-Winter method showed good agreement with GPS-TEC. During the disturbed period, IRI-2001 showed overestimation agreement for all hours, while the IRI01-corr

  2. The effects of different nutrition models on physical growth of the first 12 months of life

    Directory of Open Access Journals (Sweden)

    Nedim Samancı

    2010-12-01

    Full Text Available Objectives: The aim of this study was to investigate the effects of different feeding type on the physical growth of infants in the first 12 months of life.Materials and methods: Seventy-five infants who visited the children outpatient clinics or/and vaccination clinics regularly were recruited for the study. They were classified into breast feeding group (N=28, 14 male and 14 female, Formula feeding group (N=22, 11 male, 11 female, and mixed feeding group (N=25, 14 male, 11 female according to the feedings types before 6-months-old. The growth indices were measured and standardized growth charts for Turkish children were used for comparison.Results: The body weight and lengths of infants in the all three groups showed no statistical difference for the first 4 months according to the feeding types (p>0.05. However, growth of the infants with formula feeding and mixed feeding began to exceed the breast feed group gradually from the 4 months on. The differences of weight are statistically significant from 6-12 month and 4-12 month respectively, compared with breast feeding group (p<0.05.Conclusion: The infants with mixed or formula feeding are exposed a higher risk of overweight between 6-12 months of the first year. Breast-feeding may have a potential benefit in preventing infant obesity.

  3. Operational application and improvements of the disease risk forecast model PROCULTURE to optimize fungicides spray for the septoria leaf blotch disease in winter wheat in Luxembourg

    Directory of Open Access Journals (Sweden)

    J. Junk

    2008-05-01

    Full Text Available The model PROCULTURE has been developed by the Université Catholique de Louvain – UCL (Belgium to simulate the progress of the septoria leaf blotch disease on winter wheat during the cropping season. The model has been validated in Luxembourg for four years at four distinct representative sites. It is able to identify infection periods due to the causal agent Mycosphaerella graminicola on the last five leaf layers by combining meteorological data with phenological data from PROCULTURE's crop growth model component. The meteorological forcing consists of hourly time-series of air temperature, relative humidity and cumulative rainfall since the time of sowing, retrieved from automatic weather stations for hindcast and numerical weather prediction model outputs for the forecast periods. In order to improve the model, leaf wetness – which is one of the most important drivers for the spread of the disease – shall be added as an additional predictor. Therefore leaf wetness sensors were set up at four test sites during the 2007 growing season. To get a continuous spatial coverage of the country, it is planned to couple the PROCULTURE model offline to 12-hourly operational weather forecasts from an implementation of the Weather Research and Forecasting (WRF model for Luxembourg at 1 km resolution. Because the WRF model does not provide leaf wetness directly, an artificial neural network (ANN is used to model this parameter.

  4. Comparative study of five growth models applied to weight data from congolese infants between birth and 13 months of age.

    Science.gov (United States)

    Simondon, Kirsten B; Simondon, Francois; Delpeuch, Francis; Cornu, Andre

    1992-01-01

    Five growth models are compared using weight data from 95 rural Congolese infants between birth and 13 months of age. The objective is to find the best model in terms of goodness of fit and distribution of parameter estimates. The Infancy component of the Karlberg model, the Count model, and the Kouchi model, which are all three-parameter models, are tested together with the four- and five-parameter versions of the Reed model. The closest fits are obtained using the Reed models, followed by the Karlberg model, while the Count and Kouchi models provide poor fits. The five-parameter Reed model is not superior to the four-parameter version. Examination of mean residuals by age shows a systematic bias in neonatal weight estimation with the three-parameter models. Mean within- and between-individual correlations are especially high for the Kouchi and Reed models. Extreme skewness is observed for some parameters of the Kouchi model and of the five-parameter Reed model. Despite its high degree of collinearity, the four-parameter linear Reed model should be preferred on weight data between birth and 1 year. The I-component of the Karlberg model could be used between ages 2 and 12 months. © 1992 Wiley-Liss, Inc. Copyright © 1992 Wiley-Liss, Inc., A Wiley Company.

  5. CARVE: Monthly Atmospheric CO2 Concentrations (2009-2013) and Modeled Fluxes, Alaska

    Data.gov (United States)

    National Aeronautics and Space Administration — This data set reports monthly averages of atmospheric CO2 concentration from satellite and airborne observations between 2009 and 2013 and simulated present and...

  6. The chronobiology and neurobiology of winter seasonal affective disorder

    Science.gov (United States)

    Levitan, Robert D.

    2007-01-01

    This review summarizes research on the chronobiology and neurobiology of winter seasonal affective disorder (SAD), a recurrent subtype of depression characterized by a predictable onset in the fall/winter months and spontaneous remission in the spring/summer period. Chronobiological mechanisms related to circadian rhythms, melatonin, and photoperiodism play a significant role in many cases of SAD, and treatment of SAD can be optimized by considering individual differences in key chronobiological markers. Converging evidence also points to a role for the major monoamine neurotransmitters serotonin, norepinephrine, and dopamine in one or more aspects of SAD. Ultimately, as with other psychiatric illnesses, SAD is best considered as a complex disorder resulting from the interaction of several vulnerability factors acting at different levels, the various genetic mechanisms that underlie them, and the physical environment. Models of SAD that emphasize its potential role in human evolution will also be discussed. PMID:17969868

  7. Mid-winter Waterfowl Survey

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — The Mid-winter Waterfowl Survey is a nationwide effort to survey waterfowl in areas of major concentration on their wintering grounds and provide winter distribution...

  8. The impact of winter 2012 cold outbreak over the Northern Adriatic Sea dynamics: preliminary comparison among data and high resolution operational atmospheric models

    Science.gov (United States)

    Davolio, Silvio; Miglietta, Mario M.; Carniel, Sandro; Benetazzo, Alvise; Buzzi, Andrea; Drofa, Oxana; Falco, Pierpaolo; Fantini, Maurizio; Malguzzi, Piero; Ricchi, Antonio; Russo, Aniello; Paccagnella, Tiziana; Sclavo, Mauro

    2013-04-01

    Shelf dense water formation (DWF) events may be taking place during winter time on the broad, shallow shelf in the northern region of the Adriatic basin exposed to the Bora winds, bringing cold, dry air from the north-east down the Dinaric Alps. Indeed, the resulting intense evaporation and cooling of the shelf waters may produce North Adriatic Dense Water (NAdDW), which then tends to sink and ''cascade'' all the way to the southern basin. During these rather episodic formation processes, more frequent during winter time, the main controlling factors are intense cold wind out- breaks, the ambient water density, preconditioned during late autumn, and also other factors, e.g. river discharges. When such processes of buoyancy extraction happen, several isopycnic surfaces outcrop and very often the whole water column (20-25 m deep) may be ventilated. However, the general process of northern water masses flowing to the southern part of the Adriatic basin is complex and far from being completely understood. In order to understand and model these processes, it is mandatory to utilize high resolution meteorological forcing fields and circulation models, at least to model particular events in Adriatic marine circulation, if not its longer term (e.g., seasonal) characteristics. The use of low resolution winds in fact necessarily implies a calibration factor to better match surface fluxes and to reproduce wind-driven circulation. This is particularly evident in the case of the cross-basin Bora pattern, because the complexity and small scale of Adriatic orography is often poorly reproduced in atmospheric models, while Bora flow is composed of an alternation of high and low wind speed 'strips' crossing the Adriatic in correspondence of the fine scale (10-100 km) Balkanic orographic gaps. Within the framework of activities of the Italian flagship Project "RITMARE" and of the FIRB "DECALOGO", we focused on the current meteorological modeling capabilities to describe an event of

  9. Modeling winter wheat phenological responses to water deficits in the Unified Plant Growth Model (UPGM) component of the spatially distributed Agricultural Ecosystem Services (AgES) model

    Science.gov (United States)

    Accurately predicting phenology in crop simulation models is critical for correctly simulating crop production. While extensive work in modeling phenology has focused on the temperature response function (resulting in robust phenology models), limited work on quantifying the phenological responses t...

  10. Winter Bottom Trawl Survey

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The standardized NEFSC Winter Bottom Trawl Survey was initiated in 1992 and covered offshore areas from the Mid-Atlantic to Georges Bank. Inshore strata were covered...

  11. Deer Wintering Areas

    Data.gov (United States)

    Vermont Center for Geographic Information — Deer winter habitat is critical to the long term survival of white-tailed deer (Odocoileus virginianus) in Vermont. Being near the northern extreme of the...

  12. Varying stratospheric responses to tropical Atlantic SST forcing from early to late winter

    Science.gov (United States)

    Rao, Jian; Ren, Rongcai

    2017-11-01

    Using multiple reanalysis datasets and model simulations, we begin in this study by isolating the tropical Atlantic Ocean (TAO) sea surface temperature (SST) signals that are independent from ENSO, and then investigate their influences on the northern winter stratosphere. It is revealed that TAO SST forcing does indeed have significant effects on the northern winter stratosphere, but these effects vary from early to late winter in a way that explains the overall insignificant effect when the seasonal average is considered. The stratospheric polar vortex is anomalously weaker/warmer in November-December, stronger/colder in January-March, and weaker/warmer again in April-May during warm TAO years. The varying impacts of the TAO forcing on the extratropical stratosphere are related to a three-stage response of the extratropical troposphere to the TAO forcing during cold season. The tropospheric circulation exhibits a negative North Atlantic Oscillation-like response during early winter, an eastward propagating Rossby wave pattern in mid-to-late winter, and a meridional dipole over North America in spring. Associated with this is varying planetary wave activity in the stratosphere, manifested as an increase in early winter, a decrease in mid-to-late winter, and an increase again in spring. The varying modulation of stratospheric circulation by TAO forcing is consistently confirmed in three reanalysis datasets, and model simulations (fully coupled model and its component AGCM). The exception to the robustness of this verification is that the circumpolar wind response in the fully coupled model is relatively weaker, and that in its component AGCM appears a month later than observed.

  13. Computation of large scale currents in the Arabian Sea during winter using a semi-diagnostic model

    Digital Repository Service at National Institute of Oceanography (India)

    Shaji, C.; Bahulayan, N.; Rao, A.D.; Dube, S.K.

    A 3-dimensional, semi-diagnostic model with 331 levels in the vertical has been used for the computation of climatic circulation in the western tropical Indian Ocean. Model is driven with the seasonal mean data on wind stress, temperature...

  14. Measuring Transpiration to Regulate Winter Irrigation Rates

    Energy Technology Data Exchange (ETDEWEB)

    Samuelson, Lisa [Auburn University

    2006-11-08

    Periodic transpiration (monthly sums) in a young loblolly pine plantation between ages 3 and 6 was measured using thermal dissipation probes. Fertilization and fertilization with irrigation were better than irrigation alone in increasing transpiration of young loblolly pines during winter months, apparently because of increased leaf area in fertilized trees. Irrigation alone did not significantly increase transpiration compared with the non-fertilized and non-irrigated control plots.

  15. Implementation and evaluation of a monthly water balance model over the US on an 800 m grid

    Science.gov (United States)

    Hostetler, S. W.; Alder, J. R.

    2016-12-01

    We simulate the 1950-2010 water balance for the conterminous U.S. (CONUS) with a monthly water balance model (MWBM) using the 800 m Parameter-elevation Regression on Independent Slopes Model (PRISM) data set as model input. We employed observed snow and streamflow data sets to guide modification of the snow and potential evapotranspiration components in the default model and to evaluate model performance. Based on various metrics and sensitivity tests, the modified model yields reasonably good simulations of seasonal snowpack in the West (range of bias of ±50 mm at 68% of 713 SNOTEL sites), the gradients and magnitudes of actual evapotranspiration, and runoff (median correlation of 0.83 and median Nash-Sutcliff efficiency of 0.6 between simulated and observed annual time series at 1427 USGS gage sites). The model generally performs well along the Pacific Coast, the high elevations of the Basin and Range and over the Midwest and East, but not as well over the dry areas of the Southwest and upper Plains regions due, in part, to the apportioning of direct versus delayed runoff. Sensitivity testing and application of the MWBM to simulate the future water balance at four National Parks when driven by 30 climate models from the Climate Model Intercomparison Program Phase 5 (CMIP5) demonstrate that the model is useful for evaluating first-order, climate driven hydrologic change on monthly and annual time scales.

  16. Implementation and evaluation of a monthly water balance model over the US on an 800 m grid

    Science.gov (United States)

    Hostetler, Steven W.; Alder, Jay R.

    2016-01-01

    We simulate the 1950–2010 water balance for the conterminous U.S. (CONUS) with a monthly water balance model (MWBM) using the 800 m Parameter-elevation Regression on Independent Slopes Model (PRISM) data set as model input. We employed observed snow and streamflow data sets to guide modification of the snow and potential evapotranspiration components in the default model and to evaluate model performance. Based on various metrics and sensitivity tests, the modified model yields reasonably good simulations of seasonal snowpack in the West (range of bias of ±50 mm at 68% of 713 SNOTEL sites), the gradients and magnitudes of actual evapotranspiration, and runoff (median correlation of 0.83 and median Nash-Sutcliff efficiency of 0.6 between simulated and observed annual time series at 1427 USGS gage sites). The model generally performs well along the Pacific Coast, the high elevations of the Basin and Range and over the Midwest and East, but not as well over the dry areas of the Southwest and upper Plains regions due, in part, to the apportioning of direct versus delayed runoff. Sensitivity testing and application of the MWBM to simulate the future water balance at four National Parks when driven by 30 climate models from the Climate Model Intercomparison Program Phase 5 (CMIP5) demonstrate that the model is useful for evaluating first-order, climate driven hydrologic change on monthly and annual time scales.

  17. Prediction of two month modified Rankin Scale with an ordinal prediction model in patients with aneurysmal subarachnoid haemorrhage

    Directory of Open Access Journals (Sweden)

    Sneade Mary

    2010-09-01

    Full Text Available Abstract Background Aneurysmal subarachnoid haemorrhage (aSAH is a devastating event with a frequently disabling outcome. Our aim was to develop a prognostic model to predict an ordinal clinical outcome at two months in patients with aSAH. Methods We studied patients enrolled in the International Subarachnoid Aneurysm Trial (ISAT, a randomized multicentre trial to compare coiling and clipping in aSAH patients. Several models were explored to estimate a patient's outcome according to the modified Rankin Scale (mRS at two months after aSAH. Our final model was validated internally with bootstrapping techniques. Results The study population comprised of 2,128 patients of whom 159 patients died within 2 months (8%. Multivariable proportional odds analysis identified World Federation of Neurosurgical Societies (WFNS grade as the most important predictor, followed by age, sex, lumen size of the aneurysm, Fisher grade, vasospasm on angiography, and treatment modality. The model discriminated moderately between those with poor and good mRS scores (c statistic = 0.65, with minor optimism according to bootstrap re-sampling (optimism corrected c statistic = 0.64. Conclusion We presented a calibrated and internally validated ordinal prognostic model to predict two month mRS in aSAH patients who survived the early stage up till a treatment decision. Although generalizability of the model is limited due to the selected population in which it was developed, this model could eventually be used to support clinical decision making after external validation. Trial Registration International Standard Randomised Controlled Trial, Number ISRCTN49866681

  18. A hybrid approach to monthly streamflow forecasting: Integrating hydrological model outputs into a Bayesian artificial neural network

    Science.gov (United States)

    Humphrey, Greer B.; Gibbs, Matthew S.; Dandy, Graeme C.; Maier, Holger R.

    2016-09-01

    Monthly streamflow forecasts are needed to support water resources decision making in the South East of South Australia, where baseflow represents a significant proportion of the total streamflow and soil moisture and groundwater are important predictors of runoff. To address this requirement, the utility of a hybrid monthly streamflow forecasting approach is explored, whereby simulated soil moisture from the GR4J conceptual rainfall-runoff model is used to represent initial catchment conditions in a Bayesian artificial neural network (ANN) statistical forecasting model. To assess the performance of this hybrid forecasting method, a comparison is undertaken of the relative performances of the Bayesian ANN, the GR4J conceptual model and the hybrid streamflow forecasting approach for producing 1-month ahead streamflow forecasts at three key locations in the South East of South Australia. Particular attention is paid to the quantification of uncertainty in each of the forecast models and the potential for reducing forecast uncertainty by using the hybrid approach is considered. Case study results suggest that the hybrid models developed in this study are able to take advantage of the complementary strengths of both the ANN models and the GR4J conceptual models. This was particularly the case when forecasting high flows, where the hybrid models were shown to outperform the two individual modelling approaches in terms of the accuracy of the median forecasts, as well as reliability and resolution of the forecast distributions. In addition, the forecast distributions generated by the hybrid models were up to 8 times more precise than those based on climatology; thus, providing a significant improvement on the information currently available to decision makers.

  19. Northern winter stratospheric temperature and ozone responses to ENSO inferred from an ensemble of Chemistry Climate Models

    Directory of Open Access Journals (Sweden)

    W. Tian

    2009-11-01

    Full Text Available The connection between the El Niño Southern Oscillation (ENSO and the Northern polar stratosphere has been established from observations and atmospheric modeling. Here a systematic inter-comparison of the sensitivity of the modeled stratosphere to ENSO in Chemistry Climate Models (CCMs is reported. This work uses results from a number of the CCMs included in the 2006 ozone assessment. In the lower stratosphere, the mean of all model simulations reports a warming of the polar vortex during strong ENSO events in February–March, consistent with but smaller than the estimate from satellite observations and ERA40 reanalysis. The anomalous warming is associated with an anomalous dynamical increase of column ozone north of 70° N that is accompanied by coherent column ozone decrease in the Tropics, in agreement with that deduced from the NIWA column ozone database, implying an increased residual circulation in the mean of all model simulations during ENSO. The spread in the model responses is partly due to the large internal stratospheric variability and it is shown that it crucially depends on the representation of the tropospheric ENSO teleconnection in the models.

  20. Evaluation of the Community Multiscale Air Quality Model for Simulating Winter Ozone Formation in the Uinta Basin with Intensive Oil and Gas Production

    Science.gov (United States)

    Matichuk, R.; Tonnesen, G.; Luecken, D.; Roselle, S. J.; Napelenok, S. L.; Baker, K. R.; Gilliam, R. C.; Misenis, C.; Murphy, B.; Schwede, D. B.

    2015-12-01

    The western United States is an important source of domestic energy resources. One of the primary environmental impacts associated with oil and natural gas production is related to air emission releases of a number of air pollutants. Some of these pollutants are important precursors to the formation of ground-level ozone. To better understand ozone impacts and other air quality issues, photochemical air quality models are used to simulate the changes in pollutant concentrations in the atmosphere on local, regional, and national spatial scales. These models are important for air quality management because they assist in identifying source contributions to air quality problems and designing effective strategies to reduce harmful air pollutants. The success of predicting oil and natural gas air quality impacts depends on the accuracy of the input information, including emissions inventories, meteorological information, and boundary conditions. The treatment of chemical and physical processes within these models is equally important. However, given the limited amount of data collected for oil and natural gas production emissions in the past and the complex terrain and meteorological conditions in western states, the ability of these models to accurately predict pollution concentrations from these sources is uncertain. Therefore, this presentation will focus on understanding the Community Multiscale Air Quality (CMAQ) model's ability to predict air quality impacts associated with oil and natural gas production and its sensitivity to input uncertainties. The results will focus on winter ozone issues in the Uinta Basin, Utah and identify the factors contributing to model performance issues. The results of this study will help support future air quality model development, policy and regulatory decisions for the oil and gas sector.

  1. Validating satellite derived and modelled sea-ice drift in the Laptev Sea with in situ measurements from the winter of 2007/2008

    Directory of Open Access Journals (Sweden)

    Polona Rozman

    2011-08-01

    Full Text Available A correct representation of the ice movement in an Arctic sea-ice–ocean coupled model is essential for a realistic sea-ice and ocean simulation. The aim of this study is to validate the observational and simulated sea-ice drift for the Laptev Sea Shelf region with in situ measurements from the winter of 2007/08. Several satellite remote-sensing data sets are first compared to mooring measurements and afterwards to the sea-ice drift simulated by the coupled sea-ice–ocean model. The different satellite products have a correlation to the in situ data ranging from 0.56 to 0.86. The correlations of sea-ice direction or individual drift vector components between the in situ data and the observations are high, about 0.8. Similar correlations are achieved by the model simulations. The sea-ice drift speed derived from the model and from some satellite products have only moderate correlations of about 0.6 to the in situ record. The standard errors for the satellite products and model simulations drift components are similar to the errors of the satellite products in the central Arctic and are about 0.03 m/s. The fast-ice parameterization implementation in the model was also successfully tested for its influence on the sea-ice drift. In contrast to the satellite products, the model drift simulations have a full temporal and spatial coverage and results are reliable enough to use as sea-ice drift estimates on the Laptev Sea Shelf.

  2. Sensitivity of the Himalayan orography representation in simulation of winter precipitation using Regional Climate Model (RegCM) nested in a GCM

    Science.gov (United States)

    Tiwari, P. R.; Kar, S. C.; Mohanty, U. C.; Dey, S.; Sinha, P.; Shekhar, M. S.

    2017-12-01

    The role of the Himalayan orography representation in a Regional Climate Model (RegCM4) nested in NCMRWF global spectral model is examined in simulating the winter circulation and associated precipitation over the Northwest India (NWI; 23°-37.5°N and 69°-85°E) region. For this purpose, nine different set of orography representations for nine distinct precipitation years (three years each for wet, normal and dry) have been considered by increasing (decreasing) 5, 10, 15, and 20% from the mean height (CNTRL) of the Himalaya in RegCM4 model. Validation with various observations revealed a good improvement in reproducing the precipitation intensity and distribution with increased model height compared to the results obtained from CNTRL and reduced orography experiments. Further it has been found that, increase in height by 10% (P10) increases seasonal precipitation about 20%, while decrease in height by 10% (M10) results around 28% reduction in seasonal precipitation as compared to CNTRL experiment over NWI region. This improvement in precipitation simulation comes due to better representation of vertical pressure velocity and moisture transport as these factors play an important role in wintertime precipitation processes over NWI region. Furthermore, a comparison of model-simulated precipitation with observed precipitation at 17 station locations has been also carried out. Overall, the results suggest that when the orographic increment of 10% (P10) is applied on RegCM4 model, it has better skill in simulating the precipitation over the NWI region and this model is a useful tool for further regional downscaling studies.

  3. Assessment of Brown Bear\\'s (Ursus arctos syriacus Winter Habitat Using Geographically Weighted Regression and Generalized Linear Model in South of Iran

    Directory of Open Access Journals (Sweden)

    A. A. Zarei

    2016-03-01

    Full Text Available Winter dens are one of the important components of brown bear's (Ursus arctos syriacus habitat, affecting their reproduction and survival. Therefore identification of factors affecting the habitat selection and suitable denning areas in the conservation of our largest carnivore is necessary. We used Geographically Weighted Logistic Regression (GWLR and Generalized Linear Model (GLM for modeling suitability of denning habitat in Kouhkhom region in Fars province. In the present research, 20 dens (presence locations and 20 caves where signs of bear were not found (absence locations were used as dependent variables and six environmental factors were used for each location as independent variables. The results of GLM showed that variables of distance to settlements, altitude, and distance to water were the most important parameters affecting suitability of the brown bear's denning habitat. The results of GWLR showed the significant local variations in the relationship between occurrence of brown bear dens and the variable of distance to settlements. Based on the results of both models, suitable habitats for denning of the species are impassable areas in the mountains and inaccessible for humans.

  4. Diagnosing sea ice from the north american multi model ensemble and implications on mid-latitude winter climate

    Science.gov (United States)

    Elders, Akiko; Pegion, Kathy

    2017-12-01

    Arctic sea ice plays an important role in the climate system, moderating the exchange of energy and moisture between the ocean and the atmosphere. An emerging area of research investigates how changes, particularly declines, in sea ice extent (SIE) impact climate in regions local to and remote from the Arctic. Therefore, both observations and model estimates of sea ice become important. This study investigates the skill of sea ice predictions from models participating in the North American Multi-Model Ensemble (NMME) project. Three of the models in this project provide sea-ice predictions. The ensemble average of these models is used to determine seasonal climate impacts on surface air temperature (SAT) and sea level pressure (SLP) in remote regions such as the mid-latitudes. It is found that declines in fall SIE are associated with cold temperatures in the mid-latitudes and pressure patterns across the Arctic and mid-latitudes similar to the negative phase of the Arctic Oscillation (AO). These findings are consistent with other studies that have investigated the relationship between declines in SIE and mid-latitude weather and climate. In an attempt to include additional NMME models for sea-ice predictions, a proxy for SIE is used to estimate ice extent in the remaining models, using sea surface temperature (SST). It is found that SST is a reasonable proxy for SIE estimation when compared to model SIE forecasts and observations. The proxy sea-ice estimates also show similar relationships to mid-latitude temperature and pressure as the actual sea-ice predictions.

  5. Washington Maritime NWRC: Initial Survey Instructions for Winter Wildlife Survey

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — Due to the logistical challenges of accessing this refuge during the winter months, information on nonbreeding species use of refuge islands is very limited. This...

  6. A Conditionally Beta Distributed Time-Series Model With Application to Monthly US Corporate Default Rates

    DEFF Research Database (Denmark)

    Nielsen, Thor Pajhede

    2017-01-01

    suggested by Ferrari and Cribari-Neto (2004). Our model is a generalization of the βARMA model proposed in Rocha and Cribari-Neto (2009), which we generalize to allow for covariates and a ARCH type structure in the precision parameter. We also highlight some errors in their derivations of the score...

  7. a multi-period markov model for monthly rainfall in lagos, nigeria

    African Journals Online (AJOL)

    PUBLICATIONS1

    Many models available for this were developed and tested in developed countries in ... Keywords: Markov, multi-period ,rainfall model ... linearly dependent on that at the immediately ... More recently Artificial neural Net- ...... neural network for flood forecasting, Neural ... logical uncertainty using quantile regression:.

  8. Future changes in European winter storm losses and extreme wind speeds inferred from GCM and RCM multi-model simulations

    Directory of Open Access Journals (Sweden)

    M. G. Donat

    2011-05-01

    Full Text Available Extreme wind speeds and related storm loss potential in Europe have been investigated using multi-model simulations from global (GCM and regional (RCM climate models. Potential future changes due to anthropogenic climate change have been analysed from these simulations following the IPCC SRES A1B scenario. The large number of available simulations allows an estimation of the robustness of detected future changes. All the climate models reproduced the observed spatial patterns of wind speeds, although some models displayed systematic biases. A storm loss model was applied to the GCM and RCM simulated wind speeds, resulting in realistic mean loss amounts calculated from 20th century climate simulations, although the inter-annual variability of losses is generally underestimated. In future climate simulations, enhanced extreme wind speeds were found over northern parts of Central and Western Europe in most simulations and in the ensemble mean (up to 5%. As a consequence, the loss potential is also higher in these regions, particularly in Central Europe. Conversely, a decrease in extreme wind speeds was found in Southern Europe, as was an associated reduction in loss potential. There was considerable spread in the projected changes of individual ensemble members, with some indicating an opposite signature to the ensemble mean. Downscaling of the large-scale simulations with RCMs has been shown to be an important source of uncertainty. Even RCMs with identical boundary forcings can show a wide range of potential changes. The robustness of the projected changes was estimated using two different measures. First, the inter-model standard deviation was calculated; however, it is sensitive to outliers and thus displayed large uncertainty ranges. Second, a multi-model combinatorics approach considered all possible sub-ensembles from GCMs and RCMs, hence taking into account the arbitrariness of model selection for multi-model studies. Based on all available

  9. Examining a Partial Biopsychosocial Model for Monthly Alcohol, Tobacco, and Marijuana Use Among Adolescents.

    Science.gov (United States)

    Smith, Matthew Lee; Barry, Adam E; Merianos, Ashley L

    Alcohol, tobacco, and marijuana are commonly used substances among adolescents. In the context of the Biopsychosocial Model (BPSM), this study investigated the relationships between psychological and normative factors associated with adolescent alcohol, tobacco, and marijuana use. Data were analyzed from 1053 middle and high school students. Structural equation modeling was used to examine the relationships between BPSM constructs. Results indicate that latent constructs of the BPSM are significant antecedent factors to alcohol, tobacco, and marijuana use; however, the relationships between study constructs were inconsistent with those theorized by BPSM. Findings support the importance of theory testing for complex models applied to new topics and new populations.

  10. Assimilating a synthetic Kalman filter leaf area index series into the WOFOST model to improve regional winter wheat yield estimation

    Science.gov (United States)

    The scale mismatch between remotely sensed observations and crop growth models simulated state variables decreases the reliability of crop yield estimates. To overcome this problem, we used a two-step data assimilation phases: first we generated a complete leaf area index (LAI) time series by combin...

  11. Parameter-elevation Regressions on Independent Slopes Model Monthly Climate Data for the Continental United States.

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — This dataset was created using the PRISM (Parameter-elevation Regressions on Independent Slopes Model) climate mapping system, developed by Dr. Christopher Daly,...

  12. An extreme learning machine model for the simulation of monthly mean streamflow water level in eastern Queensland.

    Science.gov (United States)

    Deo, Ravinesh C; Şahin, Mehmet

    2016-02-01

    A predictive model for streamflow has practical implications for understanding the drought hydrology, environmental monitoring and agriculture, ecosystems and resource management. In this study, the state-or-art extreme learning machine (ELM) model was utilized to simulate the mean streamflow water level (Q WL) for three hydrological sites in eastern Queensland (Gowrie Creek, Albert, and Mary River). The performance of the ELM model was benchmarked with the artificial neural network (ANN) model. The ELM model was a fast computational method using single-layer feedforward neural networks and randomly determined hidden neurons that learns the historical patterns embedded in the input variables. A set of nine predictors with the month (to consider the seasonality of Q WL); rainfall; Southern Oscillation Index; Pacific Decadal Oscillation Index; ENSO Modoki Index; Indian Ocean Dipole Index; and Nino 3.0, Nino 3.4, and Nino 4.0 sea surface temperatures (SSTs) were utilized. A selection of variables was performed using cross correlation with Q WL, yielding the best inputs defined by (month; P; Nino 3.0 SST; Nino 4.0 SST; Southern Oscillation Index (SOI); ENSO Modoki Index (EMI)) for Gowrie Creek, (month; P; SOI; Pacific Decadal Oscillation (PDO); Indian Ocean Dipole (IOD); EMI) for Albert River, and by (month; P; Nino 3.4 SST; Nino 4.0 SST; SOI; EMI) for Mary River site. A three-layer neuronal structure trialed with activation equations defined by sigmoid, logarithmic, tangent sigmoid, sine, hardlim, triangular, and radial basis was utilized, resulting in optimum ELM model with hard-limit function and architecture 6-106-1 (Gowrie Creek), 6-74-1 (Albert River), and 6-146-1 (Mary River). The alternative ELM and ANN models with two inputs (month and rainfall) and the ELM model with all nine inputs were also developed. The performance was evaluated using the mean absolute error (MAE), coefficient of determination (r (2)), Willmott's Index (d), peak deviation (P dv), and Nash

  13. Payment mechanisms for winter road maintenance services

    Directory of Open Access Journals (Sweden)

    Adel Abdi

    2013-12-01

    Full Text Available In countries with severe winters a major part of the annual budget for road maintenance is allocated on performance of winter road maintenance tasks. Finding appropriate remuneration forms to compensate entrepreneurs for performed road measures during winter is not an easy task in order to minimise or eliminate disputes and satisfy both client organisations and contractors. On the other hand improper reimbursement models lead either to the client’s annual budget imbalance due to unnecessary cost overruns or affect contractor’s cash-flow. Such cases in turn affect just-in-time winter road maintenance and then traffic safety. To solve such problems, a number of countries in cold regions like Sweden have developed different remuneration models based more on weather data called Weather Index. Therefore the objective of this paper is to investigate and evaluate the payment models applied in Sweden. The study uses a number of approaches namely; domestic questionnaire survey, analysis of a number of contract documents, a series of meetings with the project managers and an international benchmarking. The study recognised four remuneration models for winter maintenance service of which one based on weather data statistics. The study reveals the payment model based on weather data statistics is only applied for the roads with higher traffic flow and the model generates most uncertainty.

  14. Observation and modelling of the OH, HO_{2} and RO_{2} radicals at a suburban site of Beijing (Huairou) in winter 2016

    Science.gov (United States)

    Tan, Zhaofeng; Lu, Keding; Ma, Xuefei; Birger, Bohn; Broch, Sebastian; Fuchs, Hendrik; Hofzumahaus, Andreas; Holland, Frank; Li, Xin; Liu, Yuhan; Novelli, Anna; Rohrer, Franz; Shao, Min; Wang, Haichao; Wu, Yusheng; Zeng, Limin; Kiendler-Scharr, Astrid; Wahner, Andreas; Zhang, Yuanhang

    2017-04-01

    A comprehensive field campaign was carried out in winter 2016 in Huairou, a small town located 60 km northeast of Beijing downtown. Concentrations of OH, HO2and RO2 radicals were measured by a laser induced fluorescence instrument. Radical concentrations were smaller than during summer because of reduced solar radiation. Maximum hourly averaged OH, HO2 and RO2 radical concentrations were (3±2)×106cm-3, (8±6)×107 cm-3 and (7±5)×107 cm-3, respectively. Chemical modulation measurements were applied on a few days showing no significant OH interference for different chemical conditions. HONO and HCHO photolysis were found to be the most important primary source of ROx radicals. OH reactivity, the inverse of the OH radical lifetime, was also measured by a laser-photolysis and laser induced fluorescence instrument. In general, CO and NOx were the dominated OH reactants which contributed more than half of the total OH reactivity. The relative high OH concentrations in polluted episode enabled a fast oxidation of fresh emitted pollutants and the formation of secondary products. The observed radical concentrations were compared with the results from a chemical box model. The model is capable of reproducing radical concentrations in the moderate NOx conditions but has difficulty in both the low and high NOx regimes. The underestimation of RO2 radical concentrations in the high NOx conditions indicate a missing RO2 source.

  15. The usefulness of fungicide mixtures and alternation for delaying the selection for resistance in populations of Mycosphaerella graminicola on winter wheat: a modeling analysis.

    Science.gov (United States)

    Hobbelen, P H F; Paveley, N D; Oliver, R P; van den Bosch, F

    2013-07-01

    A fungicide resistance model (reported and tested previously) was amended to describe the development of resistance in Mycosphaerella graminicola populations in winter wheat (Triticum aestivum) crops in two sets of fields, connected by spore dispersal. The model was used to evaluate the usefulness of concurrent, alternating, or mixture use of two high-resistance-risk fungicides as resistance management strategies. We determined the effect on the usefulness of each strategy of (i) fitness costs of resistance, (ii) partial resistance to fungicides, (iii) differences in the dose-response curves and decay rates between fungicides, and (iv) different frequencies of the double-resistant strain at the start of a treatment strategy. Parameter values for the quinine outside inhibitor pyraclostrobin were used to represent two fungicides with differing modes of action. The effectiveness of each strategy was quantified as the maximum number of growing seasons that disease was effectively controlled in both sets of fields. For all scenarios, the maximum effective lives achieved by the use of the strategies were in the order mixtures ≥ alternation ≥ concurrent use. Mixtures were of particular benefit where the pathogen strain resistant to both modes of action incurred a fitness penalty or was present at a low initial frequency.

  16. The influence of winter convection on primary production: A parameterisation using a hydrostatic three-dimensional biogeochemical model

    DEFF Research Database (Denmark)

    Grosse, Fabian; Lindemann, Christian; Pätch, Johannes

    2014-01-01

    In the recent past observational and modelling studies have shown that the vertical displacement of water parcels, and therefore, phytoplankton particles in regions of deep-reaching convection plays a key role in latewinter/ early spring primary production. The underlying mechanism describes how...... convection cells capture living phytoplankton cells and recurrently expose them to sunlight. This study presents a parameterisation alled ‘phytoconvection’which focusses on the influence of convection on primary production. This parameterisationwas implemented into a three-dimensional physical......–biogeochemical model and applied to the Northwestern European Continental Shelf and areas of the adjacent Northeast Atlantic. The simulation was compared to a ‘conventional’ parameterisation with respect to its influence on phytoplankton concentrations during the annual cycle and its effect on the carbon cycle...

  17. Assessing the impacts of future climate conditions on the effectiveness of winter cover crops in reducing nitrate loads into the Chesapeake Bay Watershed using SWAT model

    Science.gov (United States)

    Lee, Sangchul; Sadeghi, Ali M.; Yeo, In-Young; McCarty, Gregory W.; Hively, W. Dean

    2017-01-01

    Winter cover crops (WCCs) have been widely implemented in the Coastal Plain of the Chesapeake Bay watershed (CBW) due to their high effectiveness at reducing nitrate loads. However, future climate conditions (FCCs) are expected to exacerbate water quality degradation in the CBW by increasing nitrate loads from agriculture. Accordingly, the question remains whether WCCs are sufficient to mitigate increased nutrient loads caused by FCCs. In this study, we assessed the impacts of FCCs on WCC nitrate reduction efficiency on the Coastal Plain of the CBW using Soil and Water Assessment Tool (SWAT) model. Three FCC scenarios (2085 – 2098) were prepared using General Circulation Models (GCMs), considering three Intergovernmnental Panel on Climate Change (IPCC) Special Report on Emissions Scenarios (SRES) greenhouse gas emission scenarios. We also developed six representative WCC implementation scenarios based on the most commonly used planting dates and species of WCCs in this region. Simulation results showed that WCC biomass increased by ~ 58 % under FCC scenarios, due to climate conditions conducive to the WCC growth. Prior to implementing WCCs, annual nitrate loads increased by ~ 43 % under FCC scenarios compared to the baseline scenario (2001 – 2014). When WCCs were planted, annual nitrate loads were substantially reduced by ~ 48 % and WCC nitrate reduction efficiency water ~ 5 % higher under FCC scenarios relative to the baseline. The increase rate of WCC nitrate reduction efficiency varied by FCC scenarios and WCC planting methods. As CO2 concentration was higher and winters were warmer under FCC scenarios, WCCs had greater biomass and therefore showed higher nitrate reduction efficiency. In response to FCC scenarios, the performance of less effective WCC practices (e.g., barley, wheat, and late planting) under the baseline indicated ~ 14 % higher increase rate of nitrate reduction efficiency compared to ones with better effectiveness under the baseline (e

  18. Feasibility study of a geostatistical modelling of monthly maximum stream temperatures in a multivariate space

    Science.gov (United States)

    Guillemette, Nicolas; St-Hilaire, André; Ouarda, Taha B. M. J.; Bergeron, Normand; Robichaud, Élaine; Bilodeau, Laurent

    2009-01-01

    SummaryHealthy river conditions through optimal thermal regime controls water quality as well as the availability and distribution of fish habitat. A multivariate and geostatistical approach was developed to estimate maximum stream temperatures at a large basin scale. The methodology relies on the construction of a physiographical space using characteristics of gauging stations by testing two multivariate methods: principal components analysis (PCA) and canonical correlation analysis (CCA). Within the physiographical space, a geostatistical technique called ordinary kriging was then used to interpolate stream temperatures. Data from 12 temperature monitoring stations during July 1996 and July 1997 were used to estimate monthly maximum temperature. Results from the proposed approach were evaluated by comparing kriging performance obtained using both multivariate methods. Cross-validation technique has been performed on both approaches and satisfactory results were obtained. Kriging in the CCA physiographical space leads to better results because this approach seems more adapted to link physiographical information with specific water temperature. In addition, CCA requires less physiographical information than PCA (i.e. 10 metrics for PCA vs 8 metrics for CCA) to provide more satisfactory results (up to 15% decrease in RMSEr). In physiographical space, the gauging stations were found to cluster, potentially providing information to improve the accuracy of interpolation in that space. An example is provided to illustrate how to estimate one of the stream temperature properties at ungauged stations using the PCA algorithm. The relevance of the results regarding the quality of fish habitats of the Moisie river is discussed.

  19. Application of IEUBK model in lead risk assessment of children aged 61–84 months old in central China

    Energy Technology Data Exchange (ETDEWEB)

    Li, Yanyan [MOE Key Lab of Environment and Health, Institute of Environmental Medicine, School of Public Health, Tongji Medical College, Huazhong University of Science & Technology, Wuhan, Hubei (China); Hu, Jia [Suzhou Center for Disease Prevention and Control, Suzhou, Jiangsu (China); Wu, Wei [MOE Key Lab of Environment and Health, Institute of Environmental Medicine, School of Public Health, Tongji Medical College, Huazhong University of Science & Technology, Wuhan, Hubei (China); Liu, Shuyun [Department of Epidemiology and Biostatistics, School of Public Health, Tongji Medical College, Huazhong University of Science & Technology, Wuhan, Hubei (China); Li, Mei [Hanyang Center for Disease Prevention and Control, Wuhan, Hubei (China); Yao, Na; Chen, Jianwei [MOE Key Lab of Environment and Health, Institute of Environmental Medicine, School of Public Health, Tongji Medical College, Huazhong University of Science & Technology, Wuhan, Hubei (China); Ye, Linxiang [Department of Epidemiology and Biostatistics, School of Public Health, Tongji Medical College, Huazhong University of Science & Technology, Wuhan, Hubei (China); Wang, Qi, E-mail: lwq95@126.com [MOE Key Lab of Environment and Health, Institute of Environmental Medicine, School of Public Health, Tongji Medical College, Huazhong University of Science & Technology, Wuhan, Hubei (China); Department of Epidemiology and Biostatistics, School of Public Health, Tongji Medical College, Huazhong University of Science & Technology, Wuhan, Hubei (China); Zhou, Yikai, E-mail: zhouyk@mails.tjmu.edu.cn [MOE Key Lab of Environment and Health, Institute of Environmental Medicine, School of Public Health, Tongji Medical College, Huazhong University of Science & Technology, Wuhan, Hubei (China)

    2016-01-15

    Few studies have focused on the accuracy of using the Integrated Exposure Uptake Biokinetic (IEUBK) model in Chinese children with site- and age-specific exposure data. This study aimed to validate the accuracy and sensitivity of the IEUBK model in lead risk assessment of Chinese children aged 61–84 months old. A total of 760 children were enrolled from two respective counties in Central China by using random cluster sampling method. Blood lead levels (BLLs) of all subjects were determined using graphite furnace atomic absorption spectrometry, as well as that in the environmental media, such as air, drinking water, soil, dust and food. Age- and site-specific time-activity patterns and water consumption were evaluated by using questionnaires for children. Exposure parameters including outdoor and indoor activity time, ventilation rate and water consumption in this study were different from the default values of the IEUBK model. Statistical analysis revealed no significant differences between the predicted and observed BLLs. Diet and soil/dust lead intake contributed approximately 83.39% (57.40%–93.84% range) and 15.18% (3.25%–41.60% range) of total lead intake, respectively. These findings showed that the IEUBK model is suitable for lead risk assessment of Chinese children aged 61–84 months old and diet acts as an important lead source. - Highlights: • The first time to fit and discuss the IEUBK model in China based on comprehensive local children exposure parameters. • Two different exposure scenarios to apply the IEUBK model in different conditions. • The first time to report the ventilation rate in Chinese children aged 61 to 84 months. • Highlight the role of dietary to lead intake for Chinese children.

  20. A multi-period Markov model for monthly rainfall in Lagos, Nigeria ...

    African Journals Online (AJOL)

    Long periods of historical hydrological data such as rainfall and streamflow which are necessary for planning and design of water resources projects, are often not available and have to be forecasted. Many models available for this were developed and tested in developed countries in temperate climates and so their ...

  1. a multi-period markov model for monthly rainfall in lagos, nigeria

    African Journals Online (AJOL)

    PUBLICATIONS1

    ). Assuming our variates are normally distributed and if ti represents a standard normal random deviate at time i, then. ) 1(. )1(. 2 r tr t a. Xi. X ai a i. −. +−. = += σ. µσµ. (6) .... limitation of the model is the fact that theoreti- cally, negative values are ...

  2. Winter temperature conditions (1670-2010) reconstructed from varved sediments, western Canadian High Arctic

    Science.gov (United States)

    Amann, Benjamin; Lamoureux, Scott F.; Boreux, Maxime P.

    2017-09-01

    Advances in paleoclimatology from the Arctic have provided insights into long-term climate conditions. However, while past annual and summer temperature have received considerable research attention, comparatively little is known about winter paleoclimate. Arctic winter is of special interest as it is the season with the highest sensitivity to climate change, and because it differs substantially from summer and annual measures. Therefore, information about past changes in winter climate is key to improve our knowledge of past forced climate variability and to reduce uncertainty in climate projections. In this context, Arctic lakes with snowmelt-fed catchments are excellent potential winter climate archives. They respond strongly to snowmelt-induced runoff, and indirectly to winter temperature and snowfall conditions. To date, only a few well-calibrated lake sediment records exist, which appear to reflect site-specific responses with differing reconstructions. This limits the possibility to resolve large-scale winter climate change prior the instrumental period. Here, we present a well-calibrated quantitative temperature and snowfall record for the extended winter season (November through March; NDJFM) from Chevalier Bay (Melville Island, NWT, Canadian Arctic) back to CE 1670. The coastal embayment has a large catchment influenced by nival terrestrial processes, which leads to high sedimentation rates and annual sedimentary structures (varves). Using detailed microstratigraphic analysis from two sediment cores and supported by μ-XRF data, we separated the nival sedimentary units (spring snowmelt) from the rainfall units (summer) and identified subaqueous slumps. Statistical correlation analysis between the proxy data and monthly climate variables reveals that the thickness of the nival units can be used to predict winter temperature (r = 0.71, pc < 0.01, 5-yr filter) and snowfall (r = 0.65, pc < 0.01, 5-yr filter) for the western Canadian High Arctic over the last

  3. Drinking behaviour in sows kept outdoors during the winter months

    DEFF Research Database (Denmark)

    Andersen, Heidi Mai-Lis; Pedersen, Lene Juul

    2014-01-01

    -proof drinking bowl were used. Theindividual sow’s water intake from the drinking bowl was measured continuously fromsix days before farrowing until weaning at seven weeks after farrowing. Temperature ofsupplied water to each drinking bowl, air temperature and rainfall was measured contin-uously. Numbers of born...... alive, stillborn and weaned piglets were recorded. The recordingperiod was divided into two temperature categories; control days (CD) with daily averageair temperature at or above 0◦C and frosty days (FD) with daily average air temperaturebelow 0◦C. The FD included data from 22 days representing 11 sows......, while the remainingobservations were defined as CD. Average water uptake from six days before farrowinguntil four weeks after farrowing was higher on FD than CD (28.9 ± 0.8 vs. 23.1 ± 1.8 l/day,P

  4. Dehydration, denitrification and ozone loss during the Arctic winter 2015/2016: Simulations with the Chemistry-Climate Model EMAC and comparison to Aura/MLS and GLORIA observations

    Science.gov (United States)

    Khosrawi, Farahnaz; Kirner, Oliver; Sinnhuber, Bjoern-Martin; Johansson, Sören; Höpfner, Michael; Santee, Michelle L.; Manney, Gloria; Froidevaux, Lucien; Ungermann, Jörn; Preusse, Peter; Friedl-Vallon, Felix; Ruhnke, Roland; Woiwode, Wolfgang; Oelhaf, Hermann; Braesicke, Peter

    2017-04-01

    The Arctic winter 2015/2016 has been one of the coldest stratospheric winters in recent years. A stable vortex formed already in early December and the early winter has been exceptionally cold. Cold pool temperatures dropped below the Nitric Acid Trihydrate (NAT) existence temperature, thus allowing Polar Stratospheric Clouds (PSCs) to form. The low temperatures in the polar stratosphere persisted until early March allowing chlorine activation and catalytic ozone destruction. Satellite observations indicate that sedimentation of PSC particles have led to denitrification as well as dehydration of stratospheric layers. Nudged model simulations of the Arctic winter 2015/2016 were performed with the atmospheric chemistry-climate model ECHAM5/MESSy Atmospheric Chemistry (EMAC) for the POLSTRACC (Polar Stratosphere in a Changing Climate) campaign. POLSTRACC was a HALO mission (High Altitude and LOng Range Research Aircraft) aiming on the investigation of the structure, composition and evolution of the Arctic Upper Troposphere Lower Stratosphere (UTLS). The chemical and physical processes involved in Arctic stratospheric ozone depletion, transport and mixing processes in the UTLS at high latitudes, polar stratospheric clouds as well as cirrus clouds were investigated. In this presentation, an overview of the chemistry and dynamics of the Arctic winter 2015/2016 as simulated with EMAC will be given. Chemical-dynamical processes such as denitrification, dehydration and ozone loss will be investigated. Comparisons to satellite observations by the Aura Microwave Limb Sounder (Aura/MLS) as well as to airborne measurements with the Gimballed Limb Observer for Radiance Imaging of the Atmosphere (GLORIA) performed onboard of HALO during the POLSTRACC campaign show that the EMAC simulations are in good agreement with observations (differences generally within ±20%). However, larger differences between model and simulations are found e.g. in the areas of denitrification. Both

  5. [Construction of a diagnostic prediction model of severe bacterial infection in febrile infants under 3 months old].

    Science.gov (United States)

    Villalobos Pinto, Enrique; Sánchez-Bayle, Marciano

    2017-03-21

    Fever is a common cause of paediatric admissions in emergency departments. An aetiological diagnosis is difficult to obtain in those less than 3 months of age, as they tend to have a higher rate of serious bacterial infection (SBI). The aim of this study is to find a predictor index of SBI in children under 3 months old with fever of unknown origin. A study was conducted on all children under 3 months of age with fever admitted to hospital, with additional tests being performed according to the clinical protocol. Rochester criteria for identifying febrile infants at low risk for SBI were also analysed. A predictive model for SBI and positive cultures was designed, including the following variables in the maximum model: C-reactive protein (CRP), procalcitonin (PCT), and meeting not less than four of the Rochester criteria. A total of 702 subjects were included, of which 22.64% had an SBI and 20.65% had positive cultures. Children who had SBI and a positive culture showed higher values of white cells, total neutrophils, CRP and PCT. A statistical significance was observed with less than 4 Rochester criteria, CRP and PCT levels, an SBI (area under the curve [AUC] 0.877), or for positive cultures (AUC 0.888). Using regression analysis a predictive index was calculated for SBI or a positive culture, with a sensitivity of 87.7 and 91%, a specificity of 70.1 and 87.7%, an LR+ of 2.93 and 3.62, and a LR- of 0.17 and 0.10, respectively. The predictive models are valid and slightly improve the validity of the Rochester criteria for positive culture in children less than 3 months admitted with fever. Copyright © 2017. Publicado por Elsevier España, S.L.U.

  6. Understanding dynamics of Martian winter polar vortex with “improved” moist-convective shallow water model

    Science.gov (United States)

    Rostami, M.; Zeitlin, V.

    2017-12-01

    We show how the properties of the Mars polar vortex can be understood in the framework of a simple shallow-water type model obtained by vertical averaging of the adiabatic “primitive” equations, and “improved” by inclusion of thermal relaxation and convective fluxes due to the phase transitions of CO 2, the major constituent of the Martian atmosphere. We perform stability analysis of the vortex, show that corresponding mean zonal flow is unstable, and simulate numerically non-linear saturation of the instability. We show in this way that, while non-linear adiabatic saturation of the instability tends to reorganize the vortex, the diabatic effects prevent this, and thus provide an explanation of the vortex form and longevity.

  7. A model for the estimation of storm losses and the identification of severe winter storms in Germany

    Directory of Open Access Journals (Sweden)

    M. Klawa

    2003-01-01

    Full Text Available A storm loss model for Germany is presented. Input data to the model are the daily maximum gust wind speeds measured at stations distributed over the country. The individual daily peak gust values are scaled with the local climatological upper 2% quantile at each station. This scaling serves to take local conditions at the stations into account, and thus permits a simple spatial interpolation of the storm field. The next step is the computation of a loss index for each storm. It is based on the excess of (scaled wind speed over the upper 2% quantile, and on population numbers in the individual districts within Germany, with the latter serving as a proxy for the spatial distribution of values that could be affected by a storm. Using wind speeds in excess of the percentile value also serves to take spatial heterogeneity of vulnerability against storms into account. The aggregated storm index gives an estimate of the severity of an individual storm. Finally, the relation between actual loss produced by a storm and the index is estimated using published annual insurance loss due to windstorm in Germany. Index values are accumulated for each year, and the relation to actual loss is computed. The average ratio for the whole reference period is eventually used. It is shown that the interannual variability of storm-related losses can be reproduced with a correlation coefficient of r = 0.96, and even individual storm damages can be estimated. Based on these evaluations we found that only 50 storms account for about 80% of insured storm losses between 1970 and 1997.

  8. European cold winter 2009-2010: How unusual in the instrumental record and how reproducible in the ARPEGE-Climat model?

    Science.gov (United States)

    Ouzeau, G.; Cattiaux, J.; Douville, H.; Ribes, A.; Saint-Martin, D.

    2011-06-01

    Boreal winter 2009-2010 made headlines for cold anomalies in many countries of the northern mid-latitudes. Northern Europe was severely hit by this harsh winter in line with a record persistence of the negative phase of the North Atlantic Oscillation (NAO). In the present study, we first provide a wider perspective on how unusual this winter was by using the recent 20th Century Reanalysis. A weather regime analysis shows that the frequency of the negative NAO was unprecedented since winter 1939-1940, which is then used as a dynamical analog of winter 2009-2010 to demonstrate that the latter might have been much colder without the background global warming observed during the twentieth century. We then use an original nudging technique in ensembles of global atmospheric simulations driven by observed sea surface temperature (SST) and radiative forcings to highlight the relevance of the stratosphere for understanding if not predicting such anomalous winter seasons. Our results demonstrate that an improved representation of the lower stratosphere is necessary to reproduce not only the seasonal mean negative NAO signal, but also its intraseasonal distribution and the corresponding increased probability of cold waves over northern Europe.

  9. Modeling monthly meteorological and agronomic frost days, based on minimum air temperature, in Center-Southern Brazil

    Science.gov (United States)

    Alvares, Clayton Alcarde; Sentelhas, Paulo César; Stape, José Luiz

    2017-09-01

    Although Brazil is predominantly a tropical country, frosts are observed with relative high frequency in the Center-Southern states of the country, affecting mainly agriculture, forestry, and human activities. Therefore, information about the frost climatology is of high importance for planning of these activities. Based on that, the aims of the present study were to develop monthly meteorological (F MET) and agronomic (F AGR) frost day models, based on minimum shelter air temperature (T MN), in order to characterize the temporal and spatial frost days variability in Center-Southern Brazil. Daily minimum air temperature data from 244 weather stations distributed across the study area were used, being 195 for developing the models and 49 for validating them. Multivariate regression models were obtained to estimate the monthly T MN, once the frost day models were based on this variable. All T MN regression models were statistically significant (p < 0.001), presenting adjusted R 2 between 0.69 and 0.90. Center-Southern Brazil is mainly hit by frosts from mid-fall (April) to mid-spring (October). The period from November to March is considered as frost-free, being very rare a frost day within that period. Monthly F MET and F AGR presented significant sigmoidal relationships with T MN (p < 0.0001), with adjusted R 2 above of 0.82. The residuals of the frost day models were random, which means that the sigmoidal models performed quite well for interpreting the frost day variability throughout the study area. The highlands of Santa Catarina, Rio Grande do Sul, São Paulo, and Minas Gerais had in average more than 25 and 13 frosts per year, respectively, for F MET and F AGR. The F MET and F AGR maps developed in this study for Center-Southern Brazil is a useful tool for farmers, foresters, and researchers, since they contribute to reduce frost spatial and temporal uncertainty, helping in planning project for strategic purposes. Furthermore, the monthly F MET and F AGR maps

  10. Winter prevalence of obligate aphid pathogen Pandora neoaphidis mycosis in the host Myzus persicae populations in southern China: modeling description and biocontrol implication.

    Science.gov (United States)

    Zhou, Xiang

    2012-01-01

    Pandora neoaphidis overwintering had been investigated by monitoring its prevalence in Myzus persicae populations in open fields. Cabbage plants in field plots were weekly taken after mycosis initiation, to count and examine the living and dead aphids infected by P. neoaphidis . Based on the field data, infection levels ( I) varied with field temperature (T), relative humidity (RH) and aphid count (numbers of living aphids per plant, N) over days ( D), fitting well to the modified logistic equation I =0.91/[1+exp(8.5+(2.0 H T H RH-20.2 NI 0) D)] ( r (2)=0.897), where H T indicated daily hours of low temperature (90% RH) and I 0 primary infection level. The model demonstrated the abiotic and biotic factors influencing P. neoaphidis mycosis development in winter, and also verifies the fungal overwintering by infecting available host aphids without a resting stage. Ultimately, P. neoaphidis mycosis reduced 81.4% of aphid populations, presenting great potential for biocontrol.

  11. Winter prevalence of obligate aphid pathogen Pandora neoaphidis mycosis in the host Myzus persicae populations in southern China: modeling description and biocontrol implication

    Directory of Open Access Journals (Sweden)

    Xiang Zhou

    2012-03-01

    Full Text Available Pandora neoaphidis overwintering had been investigated by monitoring its prevalence in Myzus persicae populations in open fields. Cabbage plants in field plots were weekly taken after mycosis initiation, to count and examine the living and dead aphids infected by P. neoaphidis. Based on the field data, infection levels (I varied with field temperature (T, relative humidity (RH and aphid count (numbers of living aphids per plant, N over days (D, fitting well to the modified logistic equation I=0.91/[1+exp(8.5+(2.0H T H RH-20.2NI0D] (r²=0.897, where H T indicated daily hours of low temperature (90% RH and I0 primary infection level. The model demonstrated the abiotic and biotic factors influencing P. neoaphidis mycosis development in winter, and also verifies the fungal overwintering by infecting available host aphids without a resting stage. Ultimately, P. neoaphidis mycosis reduced 81.4% of aphid populations, presenting great potential for biocontrol.

  12. Comparisons of Modeled and Observed Reflectivities and Fall Speeds for Snowfall of Varied Riming Degree During Winter Storms on Long Island, New York

    Science.gov (United States)

    Molthan, Andrew L.; Colle, Brian A.; Yuter, Sandra E.; Stark, David

    2016-01-01

    Derived radar reflectivity and fall speed for four Weather Research and Forecasting model bulk microphysical parameterizations (BMPs) run at 1.33 km grid spacing are compared with ground-based, vertically-pointing Ku-band radar, scanning S- band radar, and in situ measurements at Stony Brook, NY. Simulations were partitioned into periods of observed riming degree as determined manually using a stereo microscope and camera during nine winter storms. Simulations were examined to determine whether the selected BMPs captured the effects of varying riming intensities, provided a reasonable match to the vertical structure of radar reflectivity or fall speed, and whether they produced reasonable surface fall speed distributions. Schemes assuming non spherical mass-diameter relationships yielded reflectivity distributions closer to observed values. All four schemes examined in this study provided a better match to the observed, vertical structure of reflectivity during moderate riming than light riming periods. The comparison of observed and simulated snow fall speeds had mixed results. One BMP produced episodes of excessive cloud water at times, resulting in fall speeds that were too large. However, most schemes had frequent periods of little or no cloud water during moderate riming periods and thus underpredicted the snow fall speeds at lower levels. Short, 1-4 hour periods with relatively steady snow conditions were used to compare BMP and observed size and fall speed distributions. These limited data suggest the examined BMPs underpredict fall speeds of cold-type snow habits and underrepresent aggregates larger than 4 mm diameter.

  13. Model simulations of stratospheric ozone loss caused by enhanced mesospheric NOx during Arctic Winter 2003/2004

    Directory of Open Access Journals (Sweden)

    T. von Clarmann

    2008-09-01

    Full Text Available Satellite observations show that the enormous solar proton events (SPEs in October–November 2003 had significant effects on the composition of the stratosphere and mesosphere in the polar regions. After the October–November 2003 SPEs and in early 2004, significant enhancements of NOx(=NO+NO2 in the upper stratosphere and lower mesosphere in the Northern Hemisphere were observed by several satellite instruments. Here we present global full chemistry calculations performed with the CLaMS model to study the impact of mesospheric NOx intrusions on Arctic polar ozone loss processes in the stratosphere. Several model simulations are preformed with different upper boundary conditions for NOx at 2000 K potential temperature (≈50 km altitude. In our study we focus on the impact of the non-local production of NOx, which means the downward transport of enhanced NOx from the mesosphere to the stratosphere. The local production of NOx in the stratosphere is neglected. Our findings show that intrusions of mesospheric air into the stratosphere, transporting high burdens of NOx, affect the composition of the Arctic polar region down to about 400 K (≈17–18 km. We compare our simulated NOx and O3 mixing ratios with satellite observations by ACE-FTS and MIPAS processed at IMK/IAA and derive an upper limit for the ozone loss caused by enhanced mesospheric NOx. Our findings show that in the Arctic polar vortex (equivalent lat.>70° N the accumulated column ozone loss between 350–2000 K potential temperature (≈14–50 km altitude caused by the SPEs in October–November 2003 in the stratosphere is up to 3.3 DU with an upper limit of 5.5 DU until end of November. Further, we found that about 10 DU, but in any case lower than 18 DU, accumulated ozone loss additionally occurred until end of March 2004 caused by the transport of mesospheric NOx-rich air in early 2004. The solar-proton-produced NOx above 55 km due to the SPEs of October–November 2003 had a

  14. Validation of CRASH Model in Prediction of 14-day Mortality and 6-month Unfavorable Outcome of Head Trauma Patients

    Directory of Open Access Journals (Sweden)

    Behrooz Hashemi

    2016-08-01

    Full Text Available Introduction: To date, many prognostic models have been proposed to predict the outcome of patients withtraumatic brain injuries. External validation of these models in different populations is of great importancefor their generalization. The present study was designed, aiming to determine the value of CRASH prognosticmodel in prediction of 14-day mortality (14-DM and 6-month unfavorable outcome (6-MUO of patients withtraumatic brain injury. Methods: In the present prospective diagnostic test study, calibration and discriminationof CRASH model were evaluated in head trauma patients referred to the emergency department. Variablesrequired for calculating CRASH expected risks (ER, and observed 14-DM and 6-MUO were gathered. Then ERof 14-DM and 6-MUO were calculated. The patients were followed for 6 months and their 14-DM and 6-MUOwere recorded. Finally, the correlation of CRASH ER and the observed outcome of the patients was evaluated.The data were analyzed using STATA version 11.0. Results: In this study, 323 patients with the mean age of 34.0´s 19.4 years were evaluated (87.3% male. Calibration of the basic and CT models in prediction of 14-day and6-month outcome were in the desirable range (P Ç 0.05. Area under the curve in the basic model for predictionof 14-DM and 6-MUO were 0.92 (95% CI: 0.89–0.96 and 0.92 (95% CI: 0.90–0.95, respectively. In addition,area under the curve in the CT model for prediction of 14-DM and 6-MUO were 0.93 (95% CI: 0.91–0.97 and0.93 (95% CI: 0.91–0.96, respectively. There was no significant difference between the discriminations of thetwo models in prediction of 14-DM (p Æ 0.11 and 6-MUO (p Æ 0.1. Conclusion: The results of the presentstudy showed that CRASH prediction model has proper discrimination and calibration in predicting 14-DMand6-MUO of head trauma patients. Since there was no difference between the values of the basic and CT models,using the basic model is recommended to simplify the risk

  15. Ecosystem function and service quantification and valuation in a conventional winter wheat production system with DAISY model in Denmark

    DEFF Research Database (Denmark)

    Ghaley, Bhim Bahadur; Porter, John Roy

    2014-01-01

    With inevitable link between ecosystem function (EF), ecosystem services (ES) and agricultural productivity, there is a need for quantification and valuation of EF and ES in agro-ecosystems. Management practices have significant effects on soil organic matter (SOM), affecting productivity, EF...... model. At 2.6% SOM, the food and fodder production was 6.49 and 6.86tha-1year-1 respectively whereas carbon sequestration and soil water storage was 9.73tha-1year-1 and 684mmha-1year-1 respectively and nitrogen mineralisation was 83.58kgha-1year-1. At 2.6% SOM, the two EF and three ES values were US......$ 177 and US$ 2542ha-1year-1 respectively equivalent to US$ 96 and US$1370 millionyear-1 respectively in Denmark. The EF and ES quantities and values were positively correlated with SOM content. Hence, the quantification and valuation of EF and ES provides an empirical tool for optimising the EF and ES...

  16. Assessing Intelligent Models in Forecasting Monthly Rainfall by Means of Teleconnection Patterns (Case Study: Khorasan Razavi Province

    Directory of Open Access Journals (Sweden)

    Farzaneh Nazarieh

    2016-02-01

    Full Text Available Introduction: Rainfall is affected by changes in the global sea level change, especially changes in sea surface temperature SST Sea Surface Temperature and sea level pressure SLP Sea level Pressure. Climate anomalies being related to each other at large distance is called teleconnection. As physical relationships between rainfall and teleconnection patterns are not defined clearly, we used intelligent models for forecasting rainfall. The intelligent models used in this study included Fuzzy Inference Systems, neural network and Neuro-fuzzy. In this study, first the teleconnection indices that could affect rainfall in the study area were identified. Then intelligent models were trained for rainfall forecasting. Finally, the most capable model for forecasting rainfall was presented. The study area for this research is the Khorasan Razavi Province. In order to present a model for rainfall forecasting, rainfall data of seven synoptic stations including Mashhad, Golmakan, Nishapur, Sabzevar, Kashmar, Torbate and Sharks since 1991 to 2010 were used. Materials and Methods: Based on previous studies about Teleconnection Patterns in the study area, effective Teleconnection indexes were identified. After calculating the correlation between the identified teleconnection indices and rainfall in one, two and three months ahead for all stations, fourteen teleconnection indices were chosen as inputs for intelligent models. These indices include, SLP Adriatic , SLP northern Red Sea, SLP Mediterranean Sea, SLP Aral sea, SST Sea surface temperature Labrador sea, SST Oman Sea, SST Caspian Sea, SST Persian Gulf, North Pacific pattern, SST Tropical Pacific in NINO12 and NINO3 regions, North Pacific Oscillation, Trans-Nino Index, Multivariable Enso Index. Inputs of the intelligent models include fourteen teleconnection indices, latitude and altitude of each station and their outputs are the prediction of rainfall for one, two and three months ahead. For calibration of

  17. Sustainability of winter tourism in a changing climate over Kashmir Himalaya.

    Science.gov (United States)

    Dar, Reyaz Ahmad; Rashid, Irfan; Romshoo, Shakil Ahmad; Marazi, Asif

    2014-04-01

    Mountain areas are sensitive to climate change. Implications of climate change can be seen in less snow, receding glaciers, increasing temperatures, and decreasing precipitation. Climate change is also a severe threat to snow-related winter sports such as skiing, snowboarding, and cross-country skiing. The change in climate will put further pressure on the sensitive environment of high mountains. Therefore, in this study, an attempt has been made to know the impact of climate change on the snow precipitation, water resources, and winter tourism in the two famous tourist resorts of the Kashmir Valley. Our findings show that winters are getting prolonged with little snow falls on account of climate change. The average minimum and maximum temperatures are showing statistically significant increasing trends for winter months. The precipitation is showing decreasing trends in both the regions. A considerable area in these regions remains under the snow and glacier cover throughout the year especially during the winter and spring seasons. However, time series analysis of LandSat MODIS images using Normalized Difference Snow Index shows a decreasing trend in snow cover in both the regions from past few years. Similarly, the stream discharge, comprising predominantly of snow- and glacier-melt, is showing a statistically significant declining trend despite the melting of these glaciers. The predicted futuristic trends of temperature from Predicting Regional Climates for Impact Studies regional climate model are showing an increase which may enhance snow-melting in the near future posing a serious threat to the sustainability of winter tourism in the region. Hence, it becomes essential to monitor the changes in temperature and snow cover depletion in these basins in order to evaluate their effect on the winter tourism and water resources in the region.

  18. Physical activity levels of community-dwelling older adults are influenced by winter weather variables.

    Science.gov (United States)

    Jones, G R; Brandon, C; Gill, D P

    2017-07-01

    Winter weather conditions may negatively influence participation of older adults in daily physical activity (PA). Assess the influence of winter meteorological variables, day-time peak ambient temperature, windchill, humidity, and snow accumulation on the ground to accelerometer measured PA values in older adults. 50 community-dwelling older adults (77.4±4.7yrs; range 71-89; 12 females) living in Southwestern Ontario (Latitude 42.9°N Longitude 81.2° W) Canada, wore a waist-borne accelerometer during active waking hours (12h) for 7 consecutive days between February and April 2007. Hourly temperature, windchill, humidity, and snowfall accumulation were obtained from meteorological records and time locked to hourly accelerometer PA values. Regression analysis revealed significant relationships between time of day, ambient daytime high temperature and a humidity for participation in PA. Windchill temperature added no additional influence over PA acclamation already influenced by ambient day-time temperature and the observed variability in PA patterns relative to snow accumulation over the study period was too great to warrant its inclusion in the model. Most PA was completed in the morning hours and increased as the winter month's transitioned to spring (February through April). An equation was developed to adjust for winter weather conditions using temperature, humidity and time of day. Accurate PA assessment during the winter months must account for the ambient daytime high temperatures, humidity, and time of day. These older adults were more physically active during the morning hours and became more active as the winter season transitioned to spring. Copyright © 2017 Elsevier B.V. All rights reserved.

  19. Nuclear winter - Physics and physical mechanisms

    Science.gov (United States)

    Turco, R. P.; Toon, O. B.; Pollack, J. B.; Ackerman, T. P.; Sagan, C.

    1991-01-01

    The basic physics of the environmental perturbations caused by multiple nuclear detonations is explored, summarizing current knowledge of the possible physical, chemical, and biological impacts of nuclear war. Emphasis is given to the impact of the bomb-generated smoke (soot) particles. General classes of models that have been used to simulate nuclear winter are examined, using specific models as examples.

  20. Numerical simulation of a rare winter hailstorm event over Delhi, India on 17 January 2013

    KAUST Repository

    Chevuturi, A.

    2014-12-19

    This study analyzes the cause of the rare occurrence of a winter hailstorm over New Delhi/NCR (National Capital Region), India. The absence of increased surface temperature or low level of moisture incursion during winter cannot generate the deep convection required for sustaining a hailstorm. Consequently, NCR shows very few cases of hailstorms in the months of December-January-February, making the winter hail formation a question of interest. For this study, a recent winter hailstorm event on 17 January 2013 (16:00–18:00 UTC) occurring over NCR is investigated. The storm is simulated using the Weather Research and Forecasting (WRF) model with the Goddard Cumulus Ensemble (GCE) microphysics scheme with two different options: hail and graupel. The aim of the study is to understand and describe the cause of hailstorm event during over NCR with a comparative analysis of the two options of GCE microphysics. Upon evaluating the model simulations, it is observed that the hail option shows a more similar precipitation intensity with the Tropical Rainfall Measuring Mission (TRMM) observation than the graupel option does, and it is able to simulate hail precipitation. Using the model-simulated output with the hail option; detailed investigation on understanding the dynamics of hailstorm is performed. The analysis based on a numerical simulation suggests that the deep instability in the atmospheric column led to the formation of hailstones as the cloud formation reached up to the glaciated zone promoting ice nucleation. In winters, such instability conditions rarely form due to low level available potential energy and moisture incursion along with upper level baroclinic instability due to the presence of a western disturbance (WD). Such rare positioning is found to be lowering the tropopause with increased temperature gradient, leading to winter hailstorm formation.

  1. Winter in Bavaria

    Directory of Open Access Journals (Sweden)

    Anthony Stephens

    2004-08-01

    Full Text Available "A Winter In Bavaria" was written on location in Regensburg, Germany, and is the first-hand account of a cataclysm, already predicted by Nostradamus, which changed the direction of Bavarian culture forever. Anything vaguely resembling an allusion to any real person or institution is entirely coincidental, has no foundation in fact and is clearly the product of a mind estranged - except that Bavarian beer is, by and large, still to be highly recommended.

  2. Evaluation of three energy balance-based evaporation models for estimating monthly evaporation for five lakes using derived heat storage changes from a hysteresis model

    NARCIS (Netherlands)

    Duan, Z.; Bastiaanssen, W.G.M.

    2017-01-01

    The heat storage changes (Qt) can be a significant component of the energy balance in lakes, and it is important to account for Qt for reasonable estimation of evaporation at monthly and finer timescales if the energy balance-based evaporation models are used. However, Qt has been often neglected in

  3. Diagnostic model of 3-D circulation in the Arabian Sea and western equatorial Indian Ocean: Results of monthly mean sea surface topography

    Digital Repository Service at National Institute of Oceanography (India)

    Bahulayan, N.; Shaji, C.

    A three-dimensional diagnostic model has been developed to compute the monthly mean circulation and sea surface topography in the Western Tropical Indian Ocean north of 20 degrees S and west of 80 degrees E. The diagnostic model equations...

  4. Attribution of UK Winter Floods to Anthropogenic Forcing

    Science.gov (United States)

    Schaller, N.; Alison, K.; Sparrow, S. N.; Otto, F. E. L.; Massey, N.; Vautard, R.; Yiou, P.; van Oldenborgh, G. J.; van Haren, R.; Lamb, R.; Huntingford, C.; Crooks, S.; Legg, T.; Weisheimer, A.; Bowery, A.; Miller, J.; Jones, R.; Stott, P.; Allen, M. R.

    2014-12-01

    Many regions of southern UK experienced severe flooding during the 2013/2014 winter. Simultaneously, large areas in the USA and Canada were struck by prolonged cold weather. At the time, the media and public asked whether the general rainy conditions over northern Europe and the cold weather over North America were caused by climate change. Providing an answer to this question is not trivial, but recent studies show that probabilistic event attribution is feasible. Using the citizen science project weather@home, we ran over 40'000 perturbed initial condition simulations of the 2013/2014 winter. These simulations fall into two categories: one set aims at simulating the world with climate change using observed sea surface temperatures while the second set is run with sea surface temperatures corresponding to a world that might have been without climate change. The relevant modelled variables are then downscaled by a hydrological model to obtain river flows. First results show that anthropogenic climate change led to a small but significant increase in the fractional attributable risk for 30-days peak flows for the river Thames. A single number can summarize the final result from probabilistic attribution studies indicating, for example, an increase, decrease or no change to the risk of the event occurring. However, communicating this to the public, media and other scientists remains challenging. The assumptions made in the chain of models used need to be explained. In addition, extreme events, like the UK floods of the 2013/2014 winter, are usually caused by a range of factors. While heavy precipitation events can be caused by dynamic and/or thermodynamic processes, floods occur only partly as a response to heavy precipitation. Depending on the catchment, they can be largely due to soil properties and conditions of the previous months. Probabilistic attribution studies are multidisciplinary and therefore all aspects need to be communicated properly.

  5. A simple model to predict the probability of a peach (Prunus persicae tree bud to develop as a long or short shoot as a consequence of winter pruning intensity and previous year growth.

    Directory of Open Access Journals (Sweden)

    Daniele Bevacqua

    Full Text Available In many woody plants, shoots emerging from buds can develop as short or long shoots. The probability of a bud to develop as a long or short shoot relies upon genetic, environmental and management factors and controlling it is an important issue in commercial orchard. We use peach (Prunus persicae trees, subjected to different winter pruning levels and monitored for two years, to develop and calibrate a model linking the probability of a bud to develop as a long shoot to winter pruning intensity and previous year vegetative growth. Eventually we show how our model can be used to adjust pruning intensity to obtain a desired proportion of long and short shoots.

  6. A binary genetic programing model for teleconnection identification between global sea surface temperature and local maximum monthly rainfall events

    Science.gov (United States)

    Danandeh Mehr, Ali; Nourani, Vahid; Hrnjica, Bahrudin; Molajou, Amir

    2017-12-01

    The effectiveness of genetic programming (GP) for solving regression problems in hydrology has been recognized in recent studies. However, its capability to solve classification problems has not been sufficiently explored so far. This study develops and applies a novel classification-forecasting model, namely Binary GP (BGP), for teleconnection studies between sea surface temperature (SST) variations and maximum monthly rainfall (MMR) events. The BGP integrates certain types of data pre-processing and post-processing methods with conventional GP engine to enhance its ability to solve both regression and classification problems simultaneously. The model was trained and tested using SST series of Black Sea, Mediterranean Sea, and Red Sea as potential predictors as well as classified MMR events at two locations in Iran as predictand. Skill of the model was measured in regard to different rainfall thresholds and SST lags and compared to that of the hybrid decision tree-association rule (DTAR) model available in the literature. The results indicated that the proposed model can identify potential teleconnection signals of surrounding seas beneficial to long-term forecasting of the occurrence of the classified MMR events.

  7. Modelling winter organic aerosol at the European scale with CAMx: evaluation and source apportionment with a VBS parameterization based on novel wood burning smog chamber experiments

    Directory of Open Access Journals (Sweden)

    G. Ciarelli

    2017-06-01

    Full Text Available We evaluated a modified VBS (volatility basis set scheme to treat biomass-burning-like organic aerosol (BBOA implemented in CAMx (Comprehensive Air Quality Model with extensions. The updated scheme was parameterized with novel wood combustion smog chamber experiments using a hybrid VBS framework which accounts for a mixture of wood burning organic aerosol precursors and their further functionalization and fragmentation in the atmosphere. The new scheme was evaluated for one of the winter EMEP intensive campaigns (February–March 2009 against aerosol mass spectrometer (AMS measurements performed at 11 sites in Europe. We found a considerable improvement for the modelled organic aerosol (OA mass compared to our previous model application with the mean fractional bias (MFB reduced from −61 to −29 %. We performed model-based source apportionment studies and compared results against positive matrix factorization (PMF analysis performed on OA AMS data. Both model and observations suggest that OA was mainly of secondary origin at almost all sites. Modelled secondary organic aerosol (SOA contributions to total OA varied from 32 to 88 % (with an average contribution of 62 % and absolute concentrations were generally under-predicted. Modelled primary hydrocarbon-like organic aerosol (HOA and primary biomass-burning-like aerosol (BBPOA fractions contributed to a lesser extent (HOA from 3 to 30 %, and BBPOA from 1 to 39 % with average contributions of 13 and 25 %, respectively. Modelled BBPOA fractions were found to represent 12 to 64 % of the total residential-heating-related OA, with increasing contributions at stations located in the northern part of the domain. Source apportionment studies were performed to assess the contribution of residential and non-residential combustion precursors to the total SOA. Non-residential combustion and road transportation sector contributed about 30–40 % to SOA formation (with increasing

  8. Modelling winter organic aerosol at the European scale with CAMx: evaluation and source apportionment with a VBS parameterization based on novel wood burning smog chamber experiments

    Science.gov (United States)

    Ciarelli, Giancarlo; Aksoyoglu, Sebnem; El Haddad, Imad; Bruns, Emily A.; Crippa, Monica; Poulain, Laurent; Äijälä, Mikko; Carbone, Samara; Freney, Evelyn; O'Dowd, Colin; Baltensperger, Urs; Prévôt, André S. H.

    2017-06-01

    We evaluated a modified VBS (volatility basis set) scheme to treat biomass-burning-like organic aerosol (BBOA) implemented in CAMx (Comprehensive Air Quality Model with extensions). The updated scheme was parameterized with novel wood combustion smog chamber experiments using a hybrid VBS framework which accounts for a mixture of wood burning organic aerosol precursors and their further functionalization and fragmentation in the atmosphere. The new scheme was evaluated for one of the winter EMEP intensive campaigns (February-March 2009) against aerosol mass spectrometer (AMS) measurements performed at 11 sites in Europe. We found a considerable improvement for the modelled organic aerosol (OA) mass compared to our previous model application with the mean fractional bias (MFB) reduced from -61 to -29 %. We performed model-based source apportionment studies and compared results against positive matrix factorization (PMF) analysis performed on OA AMS data. Both model and observations suggest that OA was mainly of secondary origin at almost all sites. Modelled secondary organic aerosol (SOA) contributions to total OA varied from 32 to 88 % (with an average contribution of 62 %) and absolute concentrations were generally under-predicted. Modelled primary hydrocarbon-like organic aerosol (HOA) and primary biomass-burning-like aerosol (BBPOA) fractions contributed to a lesser extent (HOA from 3 to 30 %, and BBPOA from 1 to 39 %) with average contributions of 13 and 25 %, respectively. Modelled BBPOA fractions were found to represent 12 to 64 % of the total residential-heating-related OA, with increasing contributions at stations located in the northern part of the domain. Source apportionment studies were performed to assess the contribution of residential and non-residential combustion precursors to the total SOA. Non-residential combustion and road transportation sector contributed about 30-40 % to SOA formation (with increasing contributions at urban and near

  9. Application of TRMM PR and TMI Measurements to Assess Cloud Microphysical Schemes in the MM5 Model for a Winter Storm

    Science.gov (United States)

    Han, Mei; Braun, Scott A.; Olson, William S.; Persson, P. Ola G.; Bao, Jian-Wen

    2009-01-01

    . This study employs this method to evaluate the accuracy of the simulated radiative properties by the MM5 model with different microphysical schemes. It is found that the representations of particle density, size, and mass in the different schemes in the MM5 model determine the model s performance when predicting a winter storm over the eastern Pacific Ocean. Schemes lacking moderate density particles (i.e. graupel), with snow flakes that are too large, or with excessive mass of snow or graupel lead to degraded prediction of the radiative properties as observed by the TRMM satellite. This study demonstrates the uniqueness of the combination of both an active microwave sensor (PR) and passive microwave sensor (TMI) onboard TRMM on assessing the accuracy of numerical weather forecasting. It improves our understanding of the physical and radiative properties of different types of precipitation particles and provides suggestions for better representation of cloud and precipitation processes in numerical models. It would, ultimately, contribute to answering questions like "Why did it not rain when the forecast says it would?"

  10. Implementation of Cold-Cloud Processes in a Source-Oriented WRF/Chem Model to Study a Winter Storm in California

    Science.gov (United States)

    Lee, H.; Chen, S.; Kleeman, M.

    2013-12-01

    radiation schemes considered the chemistry components and the physical shape of ice crystal to more accurately calculate the atmospheric optical thickness, signal scattering albedo, and asymmetry factor. The enhanced SOWC model was implemented to study a winter storm event that occurred on February 16th, 2011, in California, and the results are compared to the measurements obtained during the CalWater field campaign.

  11. Assessing climate change impacts on winter cover crop nitrate uptake efficiency on the coastal plain of the Chesapeake Bay watershed using the SWAT model

    Science.gov (United States)

    Climate change is expected to exacerbate water quality degradation in the Chesapeake Bay watershed (CBW). Winter cover crops (WCCs) have been widely implemented in this region owing to their high effectiveness at reducing nitrate loads. However, little is known about climate change impacts on the ef...

  12. Spatial validation of large scale land surface models against monthly land surface temperature patterns using innovative performance metrics.

    Science.gov (United States)

    Koch, Julian; Siemann, Amanda; Stisen, Simon; Sheffield, Justin

    2016-04-01

    Land surface models (LSMs) are a key tool to enhance process understanding and to provide predictions of the terrestrial hydrosphere and its atmospheric coupling. Distributed LSMs predict hydrological states and fluxes, such as land surface temperature (LST) or actual evapotranspiration (aET), at each grid cell. LST observations are widely available through satellite remote sensing platforms that enable comprehensive spatial validations of LSMs. In spite of the availability of LST data, most validation studies rely on simple cell to cell comparisons and thus do not regard true spatial pattern information. This study features two innovative spatial performance metrics, namely EOF- and connectivity-analysis, to validate predicted LST patterns by three LSMs (Mosaic, Noah, VIC) over the contiguous USA. The LST validation dataset is derived from global High-Resolution-Infrared-Radiometric-Sounder (HIRS) retrievals for a 30 year period. The metrics are bias insensitive, which is an important feature in order to truly validate spatial patterns. The EOF analysis evaluates the spatial variability and pattern seasonality, and attests better performance to VIC in the warm months and to Mosaic and Noah in the cold months. Further, more than 75% of the LST variability can be captured by a single pattern that is strongly driven by air temperature. The connectivity analysis assesses the homogeneity and smoothness of patterns. The LSMs are most reliable at predicting cold LST patterns in the warm months and vice versa. Lastly, the coupling between aET and LST is investigated at flux tower sites and compared against LSMs to explain the identified LST shortcomings.

  13. Winter School Les Houches

    CERN Document Server

    Lannoo, Michel; Bastard, Gérald; Voos, Michel; Boccara, Nino

    1986-01-01

    The Winter School held in Les Houches on March 12-21, 1985 was devoted to Semiconductor Heterojunctions and Superlattices, a topic which is recognized as being now one of the most interesting and active fields in semiconductor physics. In fact, following the pioneering work of Esaki and Tsu in 1970, the study of these two-dimensional semiconductor heterostructures has developed rapidly, both from the point of view of basic physics and of applications. For instance, modulation-doped heterojunctions are nowadays currently used to investigate the quantum Hall effect and to make very fast transistors. This book contains the lectures presented at this Winter School, showing in particular that many aspects of semiconductor heterojunctions and super­ lattices were treated, extending from the fabrication of these two-dimensional systems to their basic properties and applications in micro-and opto-electron­ ics. Among the subjects which were covered, one can quote as examples: molecular beam epitaxy and metallorgani...

  14. A Method for the Monthly Electricity Demand Forecasting in Colombia based on Wavelet Analysis and a Nonlinear Autoregressive Model

    Directory of Open Access Journals (Sweden)

    Cristhian Moreno-Chaparro

    2011-12-01

    Full Text Available This paper proposes a monthly electricity forecast method for the National Interconnected System (SIN of Colombia. The method preprocesses the time series using a Multiresolution Analysis (MRA with Discrete Wavelet Transform (DWT; a study for the selection of the mother wavelet and her order, as well as the level decomposition was carried out. Given that original series follows a non-linear behaviour, a neural nonlinear autoregressive (NAR model was used. The prediction was obtained by adding the forecast trend with the estimated obtained by the residual series combined with further components extracted from preprocessing. A bibliographic review of studies conducted internationally and in Colombia is included, in addition to references to investigations made with wavelet transform applied to electric energy prediction and studies reporting the use of NAR in prediction.

  15. Validation of AquaCrop Model for Simulation of Winter Wheat Yield and Water Use Efficiency under Simultaneous Salinity and Water Stress

    Directory of Open Access Journals (Sweden)

    M. Mohammadi

    2016-02-01

    simulation of soil salinity. In general, the model accuracy for simulation yield and WP was better than simulation of biomass. The d (index of agreement values were very close to one for both varieties, which means that simulated reduction in grain yield and biomass was similar to those of measured ones. In most cases the R2 values were about one, confirming a good correlation between simulated and measured values. The NRMSE values in most cases were lower than 10% which seems to be good. The CRM values were close to zero (under- and over-estimation were negligible. Based on higher WP under deficit irrigation treatments (e.g. I3 compared to full irrigation treatments (e.g. I1 and I2, it seems logical to adopt I3 treatment, especially in Birjand as a water-short region, assigning the remaining 25% to another piece of land. By such strategy, WP would be optimized at the regional scale. Conclusion: The AquaCrop was separately and simultaneously nested calibrated and validated for all salinity treatments. The model accuracy under simultaneous case was slightly lower than that for separate case. According to the results, if the model is well calibrated for minimum and maximum irrigation treatments (full irrigation and maximum deficit irrigation, it could simulate grain yield for any other irrigation treatment in between these two limits. Adopting this approach may reduce the cost of field studies for calibrating the model, since only two irrigation treatments should be conducted in the field. AquaCrop model can be a valuable tool for modelling winter wheat grain yield, WP and biomass. The simplicity of AquaCrop, as it is less data dependent, made it to be user-friendly. Nevertheless, the performance of the model has to be evaluated, validated and fine-tuned under a wider range of conditions and crops. Keywords: Biomass, Plant modeling, Sensitivity analysis

  16. Measurements for winter road maintenance

    OpenAIRE

    Riehm, Mats

    2012-01-01

    Winter road maintenance activities are crucial for maintaining the accessibility and traffic safety of the road network at northerly latitudes during winter. Common winter road maintenance activities include snow ploughing and the use of anti-icing agents (e.g. road salt, NaCl). Since the local weather is decisive in creating an increased risk of slippery conditions, understanding the link between local weather and conditions at the road surface is critically important. Sensors are commonly i...

  17. Salmonid behaviour under winter conditions

    OpenAIRE

    Watz, Johan

    2015-01-01

    Winter conditions are believed to play an important role in the population dynamics of northern temperate stream fish, challenging the ability of fish to physiologically and behaviourally adapt. Climate change is predicted to increase both mean temperature and temperature fluctuations, especially during winter, leading to dynamic environmental conditions in terms of river ice production and flow. Therefore, knowledge about the winter ecology of stream fish is important for predicting and miti...

  18. Short-term forecasting of the chloride content in the mineral waters of the Ustroń Health Resort using SARIMA and Holt-Winters models

    Directory of Open Access Journals (Sweden)

    Dąbrowska Dominika

    2015-12-01

    Full Text Available The Ustroń S.A. Health Resort (southern Poland uses iodide-bromide mineral waters taken from Middle and Upper Devonian limestones and dolomites with a mineralisation range of 110-130 g/dm3 for curative purposes. Two boreholes - U-3 and U3-A drilled in the early 1970s were exploited. The aim of this paper is to estimate changes in mineral water quality of the Ustroń Health Resort by taking into consideration chloride content in the water from the U-3 borehole. The data has included the results of monthly analyses of chlorides from 2005 to 2015 during the tests carried out by the Mining Department of the Health Resort. The triple exponential smoothing (ETS function and the Seasonal Autoregressive Integrated Moving Average (SARIMA method of modelling time series were used for the calculations. The ability to properly forecast mineral water quality can result in a good status of the exploitation borehole and a limited number of failures in the exploitation system. Because of the good management of health resorts, it is possible to acquire more satisfied customers. The main goal of the article involves the real-time forecast accuracy, obtained results show that the proposed methods are effective for such situations. Presented methods made it possible to obtain a 24-month point and interval forecast. The results of these analyses indicate that the chloride content is forecast to be in the range of 72 to 83 g/l from 2015 to 2017. While comparing the two methods of analysis, a narrower range of forecast values and, therefore, greater accuracy were obtained for the ETS function. The good performance of the ETS model highlights its utility compared with complicated physically based numerical models.

  19. Boreal winter Arctic Oscillation as an indicator of summer SST anomalies over the western tropical Indian Ocean

    Science.gov (United States)

    Gong, Dao-Yi; Guo, Dong; Gao, Yongqi; Yang, Jing; Mao, Rui; Qu, Jingxuan; Gao, Miaoni; Li, Sang; Kim, Seong-Joong

    2017-04-01

    The inter-annual relationship between the boreal winter Arctic Oscillation (AO) and summer sea surface temperature (SST) over the western tropical Indian Ocean (TIO) for the period from 1979 to 2015 is investigated. The results show that the January-February-March AO is significantly correlated with the June-July-August SST and SST tendency. When both El Niño/Southern Oscillation (ENSO) and the Indian Ocean Dipole (IOD) variance are excluded, the winter AO is significantly correlated with the regional mean SST of the western TIO (40°-60°E and 10°S-10°N), r=0.71. The multi-month SST tendency, i.e., the SST difference of June-July-August minus April-May, is correlated with the winter AO at r=0.75. Composite analysis indicates similar warming over the western TIO. Two statistical models are established to predict the subsequent summer's SST and SST tendency. The models use the winter AO, the winter ENSO and the autumn-winter IOD indexes as predictors and explain 65 and 62 % of the variance of the subsequent summer's SST and SST tendency, respectively. Investigation of the regional air-sea fluxes and oceanic dynamics reveals that the net surface heat flux cannot account for the warming, whereas the oceanic Rossby wave plays a predominant role. During positive AO winters, the enhanced Arabian High causes stronger northern winds in the northern Indian Ocean and leads to anomalous cross-equatorial air-flow. The Ekman pumping in association with the anomalous wind stress curl in the central TIO generates a significantly deeper thermocline and above-normal sea surface height at 60°-75°E and 5°-10°S. The winter AO-forced Rossby wave propagates westward and arrives at the western coast in summer, resulting in the significant SST increase. Forced by the observed winter AO-related wind stress anomalies over the Indian Ocean, the ocean model reasonably reproduces the Rossby wave as well as the resulting surface ocean warming over the western TIO in the subsequent summer

  20. Winter Community Structure Changes in Frazil Ice and Open Water in Riverine Systems

    National Research Council Canada - National Science Library

    White, K

    2004-01-01

    ...) that examined dissolved oxygen (DO) levels and changes in river microbiology during winter, periods of low water temperature, and periods of ice-cover, with the objective of providing guidance for winter water-quality modeling...

  1. Stamena winter wheat variety

    Directory of Open Access Journals (Sweden)

    Mišić Todor

    2001-01-01

    Full Text Available Stamena is a winter wheat variety developed at the Institute of Field and Vegetable Crops in Novi Sad, Yugoslavia. It was released by the Federal Commission for varietals Approval in 1999. Stamena was developed by crossing genetically divergent and highly productive parents Lasta and Rodna (Breeders: T. Mišić. N. Mladenov, Z. Jerković and R. Jevtić. Spike is white, smooth, awn less, medium compact with 18-21 spike lets. The grain is vitreous and dark red (Triticum aestivum L. ssp. vulgar e var. lutescens. Stamena is a medium early variety, 1 day earlier than Partizanka and 3 days earlier than Jugoslavija (Table 4. It has excellent resistance to winterkilling, as in very winter hardy Partizanka. The average stem height is 78 cm, with a good resistance to lodging. Stamena has field resistance to leaf rust (Pucce, recondita tritict, horizontal resistance, which is the type of resistance that modern wheat breeding is interested in. The resistance to stem rust (Pucce, graminis tritict is good and to powdery mildew (Erysiphegraminis tritici very good. The 1000 grain mass is about 32 g and volume grain mass 81.3 kg/hi. (Table 2. Stamena is classified in the subgroup A-l. It has excellent milling and baking quality and it belong to the 1st technological group (quality enhancer. The quantity of dry gluten is about 9%. The variety Stamena is a very productive, with the genetic potential for grain above 11 t/ha suitable for growing on fertile and less fertile soils. It has started to be grown commercially in 2000.

  2. Statistical comparison of models for estimating the monthly average daily diffuse radiation at a subtropical African site

    Energy Technology Data Exchange (ETDEWEB)

    Bashahu, M. [University of Burundi, Bujumbura (Burundi). Institute of Applied Pedagogy, Department of Physics and Technology

    2003-07-01

    Nine correlations have been developed in this paper to estimate the monthly average diffuse radiation for Dakar, Senegal. A 16-year period data on the global (H) and diffuse (H{sub d}) radiation, together with data on the bright sunshine hours (N), the fraction of the sky's (Ne/8), the water vapour pressure in the air (e) and the ambient temperature (T) have been used for that purpose. A model inter-comparison based on the MBE, RMSE and t statistical tests has shown that estimates in any of the obtained correlations are not significantly different from their measured counterparts, thus all the nine models are recommended for the aforesaid location. Three of them should be particularly selected for their simplicity, universal applicability and high accuracy. Those are simple linear correlations between K{sub d} and N/N{sub d}, Ne/8 or K{sub t}. Even presenting adequate performance, the remaining correlations are either simple but less accurate, or multiple or nonlinear regressions needing one or two input variables. (author)

  3. CESM Lakes Monthly

    Data.gov (United States)

    U.S. Environmental Protection Agency — This dataset contains monthly aggregates of 2D near-surface fields from the WRF model simulations labeled "default" (using WRF default approach to setting lake...

  4. Optimal Cross Hedging Winter Canola

    OpenAIRE

    Kim, Seon-Woong; Brorsen, B. Wade; Yoon, Byung-Sam

    2014-01-01

    Winter canola in the southern Great Plains has shown large price fluctuations and there have been questions about which futures market could be used to reduce price risk. Our results indicate that the optimal futures contract to cross hedge winter canola is soybean oil futures.

  5. Winter Climate Limits Subantarctic Low Forest Growth and Establishment

    Science.gov (United States)

    Harsch, Melanie A.; McGlone, Matt S.; Wilmshurst, Janet M.

    2014-01-01

    Campbell Island, an isolated island 600 km south of New Zealand mainland (52°S, 169°E) is oceanic (Conrad Index of Continentality  = −5) with small differences between mean summer and winter temperatures. Previous work established the unexpected result that a mean annual climate warming of c. 0.6°C since the 1940's has not led to upward movement of the forest limit. Here we explore the relative importance of summer and winter climatic conditions on growth and age-class structure of the treeline forming species, Dracophyllum longifolium and Dracophyllum scoparium over the second half of the 20th century. The relationship between climate and growth and establishment were evaluated using standard dendroecological methods and local climate data from a meteorological station on the island. Growth and establishment were correlated against climate variables and further evaluated within hierarchical regression models to take into account the effect of plot level variables. Winter climatic conditions exerted a greater effect on growth and establishment than summer climatic conditions. Establishment is maximized under warm (mean winter temperatures >7 °C), dry winters (total winter precipitation <400 mm). Growth, on the other hand, is adversely affected by wide winter temperature ranges and increased rainfall. The contrasting effect of winter warmth on growth and establishment suggests that winter temperature affects growth and establishment through differing mechanisms. We propose that milder winters enhance survival of seedlings and, therefore, recruitment, but increases metabolic stress on established plants, resulting in lower growth rates. Future winter warming may therefore have complex effects on plant growth and establishment globally. PMID:24691026

  6. Nuclear Winter: Implications for civil defense

    Energy Technology Data Exchange (ETDEWEB)

    Chester, C.V.; Perry, A.M.; Hobbs, B.F.

    1988-05-01

    ''Nuclear Winter'' is the term given to the cooling hypothesized to occur in the Northern Hemisphere following a nuclear war as the result of the injection of smoke from burning cities into the atmosphere. The voluminous literature on this subject produced since the paper was published in 1983 by Turco, Toon, Ackerman, Pollack, and Sagen (TTAPS) has been reviewed. Three-dimensional global circulation models have resulted in reduced estimates of cooling---15 to 25/degree/C for a summer war and a few degrees for a winter war. More serious may be the possibility of suppression of convective precipitation by the altered temperature profiles in the atmosphere. However, very large uncertainties remain in input parameters, the models, and the results of calculations. We believe the state of knowledge about nuclear winter is sufficiently developed to conclude: Neither cold nor drought is likely to be a direct threat to human survival for populations with the wherewithal to survive normal January temperatures. The principal threat from nuclear winter is to food production, and this could present problems to third parties who are without food reserves. Loss of a crop year is neither a new nor an unexpected threat from nuclear war to the United States and the Soviet Union. Both have at least a year's food reserve at all times. Both face formidable organizational problems in distributing their reserves in a war-damaged environment. The consequences of nuclear winter could be expected to fall more heavily on the Soviet Union than the United States due to its higher latitude and less productive agriculture. This may be especially true if disturbances of rainfall amounts and distribution persist for more than a year.

  7. Sage-grouse habitat selection during winter in Alberta

    Science.gov (United States)

    Carpenter, Jennifer L.; Aldridge, Cameron L.; Boyce, Mark S.

    2010-01-01

    Greater sage-grouse (Centrocercus urophasianus) are dependent on sagebrush (Artemisia spp.) for food and shelter during winter, yet few studies have assessed winter habitat selection, particularly at scales applicable to conservation planning. Small changes to availability of winter habitats have caused drastic reductions in some sage-grouse populations. We modeled winter habitat selection by sage-grouse in Alberta, Canada, by using a resource selection function. Our purpose was to 1) generate a robust winter habitat-selection model for Alberta sage-grouse; 2) spatially depict habitat suitability in a Geographic Information System to identify areas with a high probability of selection and thus, conservation importance; and 3) assess the relative influence of human development, including oil and gas wells, in landscape models of winter habitat selection. Terrain and vegetation characteristics, sagebrush cover, anthropogenic landscape features, and energy development were important in top Akaike's Information Criterionselected models. During winter, sage-grouse selected dense sagebrush cover and homogenous less rugged areas, and avoided energy development and 2-track truck trails. Sage-grouse avoidance of energy development highlights the need for comprehensive management strategies that maintain suitable habitats across all seasons. ?? 2010 The Wildlife Society.

  8. Urban emissions of water vapor in winter

    Science.gov (United States)

    Salmon, Olivia E.; Shepson, Paul B.; Ren, Xinrong; Marquardt Collow, Allison B.; Miller, Mark A.; Carlton, Annmarie G.; Cambaliza, Maria O. L.; Heimburger, Alexie; Morgan, Kristan L.; Fuentes, Jose D.; Stirm, Brian H.; Grundman, Robert; Dickerson, Russell R.

    2017-09-01

    Elevated water vapor (H2Ov) mole fractions were occasionally observed downwind of Indianapolis, IN, and the Washington, D.C.-Baltimore, MD, area during airborne mass balance experiments conducted during winter months between 2012 and 2015. On days when an urban H2Ov excess signal was observed, H2Ov emission estimates range between 1.6 × 104 and 1.7 × 105 kg s-1 and account for up to 8.4% of the total (background + urban excess) advected flow of atmospheric boundary layer H2Ov from the urban study sites. Estimates of H2Ov emissions from combustion sources and electricity generation facility cooling towers are 1-2 orders of magnitude smaller than the urban H2Ov emission rates estimated from observations. Instances of urban H2Ov enhancement could be a result of differences in snowmelt and evaporation rates within the urban area, due in part to larger wintertime anthropogenic heat flux and land cover differences, relative to surrounding rural areas. More study is needed to understand why the urban H2Ov excess signal is observed on some days, and not others. Radiative transfer modeling indicates that the observed urban enhancements in H2Ov and other greenhouse gas mole fractions contribute only 0.1°C d-1 to the urban heat island at the surface. This integrated warming through the boundary layer is offset by longwave cooling by H2Ov at the top of the boundary layer. While the radiative impacts of urban H2Ov emissions do not meaningfully influence urban heat island intensity, urban H2Ov emissions may have the potential to alter downwind aerosol and cloud properties.

  9. Klaus Winter (1930 - 2015)

    CERN Multimedia

    2015-01-01

    We learned with great sadness that Klaus Winter passed away on 9 February 2015, after a long illness.   Klaus was born in 1930 in Hamburg, where he obtained his diploma in physics in 1955. From 1955 to 1958 he held a scholarship at the Collège de France, where he received his doctorate in nuclear physics under the guidance of Francis Perrin. Klaus joined CERN in 1958, where he first participated in experiments on π+ and K0 decay properties at the PS, and later became the spokesperson of the CHOV Collaboration at the ISR. Starting in 1976, his work focused on experiments with the SPS neutrino beam. In 1984 he joined Ugo Amaldi to head the CHARM experiment, designed for detailed studies of the neutral current interactions of high-energy neutrinos, which had been discovered in 1973 using the Gargamelle bubble chamber at the PS. The unique feature of the detector was its target calorimeter, which used large Carrara marble plates as an absorber material. From 1984 to 1991, Klau...

  10. Winter fuels report

    Energy Technology Data Exchange (ETDEWEB)

    1995-01-13

    The Winter Fuels Report is intended to provide concise, timely information to the industry, the press, policymakers, consumers, analysts, and State and local governments on the following topics: distillate fuel oil net production, imports and stocks on a US level and for all Petroleum Administration for Defense Districts (PADD) and product supplied on a US level; propane net production, imports and stocks on a US level and for PADD`s I, II, and III; natural gas supply and disposition and underground storage for the US and consumption for all PADD`s, as well as selected National average prices; residential and wholesale pricing data for heating oil and propane for those States participating in the joint Energy Information Administration (EIA)/State Heating Oil and Propane Program; crude oil and petroleum price comparisons for the US and selected cities; and a 6-10 day, 30-Day, and 90-Day outlook for temperature and precipitation and US total heating degree-days by city.

  11. Impacts of +2 °C global warming on winter tourism demand in Europe

    NARCIS (Netherlands)

    Damm, Andrea; Greuell, Wouter; Landgren, Oskar; Prettenthaler, Franz

    2017-01-01

    Increasing temperatures and snow scarce winter seasons challenge the winter tourism industry. In this study the impacts of +2 °C global warming on winter tourism demand in Europe's ski tourism related NUTS-3 regions are quantified. Using time series regression models, the relationship between

  12. Motor function deficits in the 12 month-old female 5xFAD mouse model of Alzheimer's disease.

    Science.gov (United States)

    O'Leary, T P; Robertson, A; Chipman, P H; Rafuse, V F; Brown, R E

    2018-01-30

    Motor problems occur early in some patients with Alzheimer's disease (AD) and as the disease progresses many patients develop motor dysfunction. Motor dysfunction has been reported in some mouse models of AD, including the 5xFAD mouse, thus this model may be particularly useful for studying motor dysfunction in AD. In order to determine the extent of motor dysfunction in these mice, we tested 11-13 month old female 5xFAD and wildtype (WT) control mice in a battery of motor behaviour tasks. The 5xFAD mice showed hind limb clasping, weighed less and had slower righting reflexes than WT mice. In the open field, the 5xFAD mice travelled a shorter distance than the WT mice, spent less time moving and had a slower movement speed. The 5xFAD mice fell faster than the WT mice from the balance beam, wire suspension, grid suspension and rotarod tasks, indicating dysfunctions in balance, grip strength, motor co-ordination and motor learning. The 5xFAD mice had a short, shuffling gait with a shorter stride length than WT mice and had a slower swim speed. The 5xFAD mice also failed to show an acoustic startle response, likely due to motor dysfunction and previously reported hearing impairment. The 5xFAD mice did not show deficits in the ability of peripheral motor nerves to drive muscle output, suggesting that motor impairments are not due to dysfunction in peripheral motor nerves. These results indicate that the aged 5xFAD mice are deficient in numerous motor behaviours, and suggest that these mice may prove to be a good model for studying the mechanisms of motor dysfunction in AD, and motor behaviour might prove useful for assessing the efficacy of AD therapeutics. Motor dysfunction in 5xFAD mice must also be considered in behavioural tests of sensory and cognitive function so that performance is not confounded by impaired locomotor or swimming behaviour. Copyright © 2017 Elsevier B.V. All rights reserved.

  13. Projections of thermal conditions for Poland for winters 2021?2050 in relation to atmospheric circulation

    OpenAIRE

    Piotr Piotrowski; Joanna Jędruszkiewicz

    2013-01-01

    Winter thermal conditions in Poland are largely determined by atmospheric circulation. Therefore, the projection of future temperature change should be considered in relation to changes in circulation patterns. This paper assesses the spatial variability in winter temperature in Poland in the 2021?2050 period based on the CLM, HIRHAM5 and RACMO2 models. Thermal conditions in winter have been studied in relation to the atmospheric circulation as a main factor of winter temperature change i...

  14. Winter Precipitation in North America and the Pacific-North America Pattern in GEOS-S2Sv2 Seasonal Hindcast

    Science.gov (United States)

    Li, Zhao; Molod, Andrea; Schubert, Siegfried

    2018-01-01

    Reliable prediction of precipitation remains one of the most pivotal and complex challenges in seasonal forecasting. Previous studies show that various large-scale climate modes, such as ENSO, PNA and NAO play significant role in winter precipitation variability over the Northern America. The influences are most pronounced in years of strong indices of such climate modes. This study evaluates model bias, predictability and forecast skills of monthly winter precipitation in GEOS5-S2S 2.0 retrospective forecast from 1981 to 2016, with emphasis on the forecast skill of precipitation over North America during the extreme events of ENSO, PNA and NAO by applying EOF and composite analysis.

  15. Comparison of GPS TEC variations with Holt-Winter method and IRI-2012 over Langkawi, Malaysia

    Science.gov (United States)

    Elmunim, N. A.; Abdullah, M.; Hasbi, A. M.; Bahari, S. A.

    2017-07-01

    The Total Electron Content (TEC) is the ionospheric parameter that has the main effect on radio wave propagation. Therefore, it is crucial to evaluate the performance of the TEC models for the further improvement of the ionospheric modelling in equatorial regions. This work presents an analysis of the TEC, derived from the GPS Ionospheric Scintillation and TEC Monitor (GISTM) receiver at the Langkawi station, Malaysia, located at the geographic coordinates of 6.19°N, 99.51°E and the geomagnetic coordinates of 3.39°S, 172.42°E. The diurnal, monthly and seasonal variations in 2014 of the observed GPS-TEC were compared with the statistical Holt-Winter method and a recent version of the International Reference Ionosphere model (IRI-2012), using three different topside options of an electron density, which are the IRI-2001, IRI01-corr and NeQuick. The maximum peaks of the GPS-TEC were observed in the post-noon time and the minimum was observed during the early morning time. In addition, in monthly variations the Holt-Winter and the IRI-2012 topside options showed an underestimation that was in agreement with the GPS-TEC, except for the IRI-2001 model which showed an overestimation in June, July and August. Regarding the seasonal variation of the GPS-TEC, the lowest values were observed during summer and it reached its maximum value during the equinox season. The IRI-2001 showed the highest value of percentage deviation compared to the IRI01-corr, NeQuick and Holt-Winter method. Therefore, the accuracy of the models was found to be approximately 95% in the Holt-Winter method, 75% in the IRI01-corr, 73% in the NeQuick and 66% in the IRI-2001 model. Hence, it can be inferred that the Holt-Winter method showed a higher performance and better estimates of the TEC compared to the IRI01-corr and NeQuick, while the IRI-2001 showed a poor predictive performance in the equatorial region over Malaysia.

  16. Have winter fuel payments reduced excess winter mortality in England and Wales?

    Science.gov (United States)

    Iparraguirre, J

    2015-03-01

    The historical series of excess winter mortality (EWM) in England and Wales presents a negative trend. Winter fuel payments (WFPs) are the most important benefits for people aged 65 or over directly related to Winter Mortality in the UK. This study presents a time series analysis of the direct effect of WFPs on EWM in England and Wales. We find a significant structural break in trend and volatility in the EWM series in England and Wales in 1999-2000. After controlling for a number of covariates, an ARIMA-X model finds that WFPs can account for almost half of the reduction in EWM in England and Wales since 1999/2000. Almost half of the reduction in EWM since 1999/2000 is attributable to WFPs. © The Author 2014. Published by Oxford University Press on behalf of Faculty of Public Health. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  17. STUDIES ON THE RESISTANCE TO WINTERING OF THE ITALIAN BEES APIS MELLIFERA LIGUSTICA REARED IN ROMANIA

    OpenAIRE

    MONICA PÂRVU; CORINA AURELIA ZUGRAVU; IOANA CRISTINA ANDRONIE; CARMEN BERGHEŞ; IUDITH IPATE

    2009-01-01

    The study was conducted on bee families of Apis mellifera carpatica and Apis mellifera ligustica breeds. The bees were housed in multi-storey hives. The experimental period was of 6 months. The resistance to wintering was evaluated on the basis of several apicultural indicators: mortality, feed intake during the winter, general state of the family. Mortality was 35% during wintering for the Carpathian bee and 52% for the Italian bee. The differences were very significant (p≤0.001). When winte...

  18. ALBEDO MODELS FOR SNOW AND ICE ON A FRESHWATER LAKE. (R824801)

    Science.gov (United States)

    AbstractSnow and ice albedo measurements were taken over a freshwater lake in Minnesota for three months during the winter of 1996¯1997 for use in a winter lake water quality model. The mean albedo of new snow was measured as 0.83±0.028, while the...

  19. A Comprehensive Modeling Study on Regional Climate Model (RCM Application — Regional Warming Projections in Monthly Resolutions under IPCC A1B Scenario

    Directory of Open Access Journals (Sweden)

    Md. Mujibur Rahman

    2012-10-01

    Full Text Available Some of the major dimensions of climate change include increase in surface temperature, longer spells of droughts in significant portions of the world, associated higher evapotranspiration rates, and so on. It is therefore essential to comprehend the future possible scenario of climate change in terms of global warming. A high resolution limited area Regional Climate Model (RCM can produce reasonably appropriate projections to be used for climate-scenario generation in country-scale. This paper features the development of future surface temperature projections for Bangladesh on monthly resolution for each year from 2011 to 2100 applying Providing Regional Climates for Impacts Studies (PRECIS, and it explains in detail the modeling processes including the model features, domain size selection, bias identification as well as construction of change field for the concerned climatic variable, in this case, surface temperature. PRECIS was run on a 50 km horizontal grid-spacing under the Intergovernmental Panel on Climate Change (IPCC A1B scenario and it was found to perform reasonably well in simulating future surface temperature of Bangladesh. The linear regression between observed and model simulated results of monthly average temperatures, within the 30-year period from 1971 to 2000, gives a high correlation of 0.93. The applied change field in average annual temperature shows only 0.5 °C–1 °C deviation from the observed values over the period from 2005 to 2008. Eventually, from the projected average temperature change during the years 1971–2000, it is apparent that warming in Bangladesh prevails invariably every month, which might eventually result in an average annual increase of 4 °C by the year 2100. Calculated anomalies in country-average annual temperature mostly remain on the positive side throughout the period of 2071–2100 indicating an overall up-shift. Apart from these quantitative analyses of temporal changes of temperature

  20. Human impact parameterization in global hydrological models improves estimates of monthly discharges and hydrological extremes: a multi-model validation study

    Science.gov (United States)

    Veldkamp, Ted; Ward, Philip; de Moel, Hans; Aerts, Jeroen; Muller Schmied, Hannes; Portmann, Felix; Zhao, Fang; Gerten, Dieter; Masaki, Yoshimitsu; Pokhrel, Yadu; Satoh, Yusuke; Gosling, Simon; Zaherpour, Jamal; Wada, Yoshihide

    2017-04-01

    Human impacts on freshwater resources and hydrological features form the core of present-day water related hazards, like flooding, droughts, water scarcity, and water quality issues. Driven by the societal and scientific needs to correctly model such water related hazards a fair amount of resources has been invested over the past decades to represent human activities and their interactions with the hydrological cycle in global hydrological models (GHMs). Use of these GHMs - including the human dimension - is widespread, especially in water resources research. Evaluation or comparative assessments of the ability of such GHMs to represent real-world hydrological conditions are, unfortunately, however often limited to (near-)natural river basins. Such studies are, therefore, not able to test the model representation of human activities and its associated impact on estimates of freshwater resources or assessments of hydrological extremes. Studies that did perform a validation exercise - including the human dimension and looking into managed catchments - either focused only on one hydrological model, and/or incorporated only a few data points (i.e. river basins) for validation. To date, a comprehensive comparative analysis that evaluates whether and where incorporating the human dimension actually improves the performance of different GHMs with respect to their representation of real-world hydrological conditions and extremes is missing. The absence of such study limits the potential benchmarking of GHMs and their outcomes in hydrological hazard and risk assessments significantly, potentially hampering incorporation of GHMs and their modelling results in actual policy making and decision support with respect to water resources management. To address this issue, we evaluate in this study the performance of five state-of-the-art GHMs that include anthropogenic activities in their modelling scheme, with respect to their representation of monthly discharges and hydrological

  1. Cold truths: how winter drives responses of terrestrial organisms to climate change.

    Science.gov (United States)

    Williams, Caroline M; Henry, Hugh A L; Sinclair, Brent J

    2015-02-01

    Winter is a key driver of individual performance, community composition, and ecological interactions in terrestrial habitats. Although climate change research tends to focus on performance in the growing season, climate change is also modifying winter conditions rapidly. Changes to winter temperatures, the variability of winter conditions, and winter snow cover can interact to induce cold injury, alter energy and water balance, advance or retard phenology, and modify community interactions. Species vary in their susceptibility to these winter drivers, hampering efforts to predict biological responses to climate change. Existing frameworks for predicting the impacts of climate change do not incorporate the complexity of organismal responses to winter. Here, we synthesise organismal responses to winter climate change, and use this synthesis to build a framework to predict exposure and sensitivity to negative impacts. This framework can be used to estimate the vulnerability of species to winter climate change. We describe the importance of relationships between winter conditions and performance during the growing season in determining fitness, and demonstrate how summer and winter processes are linked. Incorporating winter into current models will require concerted effort from theoreticians and empiricists, and the expansion of current growing-season studies to incorporate winter. © 2014 The Authors. Biological Reviews © 2014 Cambridge Philosophical Society.

  2. The Challenge of Winter Backpacking.

    Science.gov (United States)

    Cavanaugh, Michael; Mapes, Alan

    1981-01-01

    Tips and techniques for safe and enjoyable winter backpacking are offered. Topics covered include cross county skis, snowshoes, clothing, footwear, shelter, sleeping bags, food, hypothermia prevention, as well as general rules and requirements. (CO)

  3. Winter waterfowl survey, southeastern Alaska

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — Little is known of the total numbers of wintering waterfowl within the north pacific coastal region. The random stratified plot sampling methods used in 1980, as...

  4. Winter/Summer Monsoon Experiment

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The Winter/Summer Monsoon Experiment (MONEX) was conducted during the First Global GARP (Global Atmospheric Research Program) Experiment (FGGE). An international...

  5. Shining Light on "Dark Winter"

    National Research Council Canada - National Science Library

    Tara O'Toole; Michael Mair; Thomas V. Inglesby

    2002-01-01

    ... Security, and the Oklahoma National Memorial Institute for the Prevention of Terrorism, held a senior-level exercise entitled "Dark Winter" that simulated a covert smallpox attack on the United States...

  6. Characteristic features of winter precipitation and its variability over ...

    Indian Academy of Sciences (India)

    Northwestern parts of India receive considerable amount of precipitation during the winter months of December–March. Although, it is only about 15% of the annual precipitation, the precipitation is very important for rabi crops and to maintain the glaciers extend in the Himalaya, which melt and supply water to the rivers ...

  7. Prediction of Clearance in Neonates and Infants (≤ 3 Months of Age) for Drugs That Are Glucuronidated: A Comparative Study Between Allometric Scaling and Physiologically Based Pharmacokinetic Modeling.

    Science.gov (United States)

    Mahmood, Iftekhar; Ahmad, Tasneem; Mansoor, Najia; Sharib, S M

    2017-04-01

    The objective of this study was to evaluate the predictive performances of allometric models and a physiologically based pharmacokinetic model (PBPK) to predict clearance of glucuronidated drugs in neonates (≤ 3 months of age). From the literature, clearance values for 9 drugs (glucuronidated) for neonates and adults were obtained. Three allometric models were used to predict clearances of these glucuronidated drugs. A PBPK model was developed using the physicochemical, biopharmaceutical, and metabolic properties together with known pediatric physiology and enzymatic ontogeny. The model was first developed for adult subjects and then verified using external data and then applied to simulations in neonates. The predictive performances of allometric and PBPK models were evaluated by comparing the predicted values of clearance with the observed clearance values in the neonates. For 9 drugs, there were 13 age groups (preterm and term neonates) for which prediction error in mean clearance values within 0.5- to 1.5-fold was observed in 10 and 11 age groups by 2 allometric models and a PBPK model, respectively. The proposed allometric methods can predict mean clearances of glucuronidated drugs in preterm and term neonates (≤ 3 months of age) with reasonable accuracy (within 0.5- to 1.5-fold or 50% error) and are of practical value during neonatal drug development. The predicted mean clearance values of glucuronidated drugs in neonates ≤ 3 months of age by 2 allometric methods were comparable with the PBPK model. © 2016, The American College of Clinical Pharmacology.

  8. Disturbance to wintering western snowy plovers

    Science.gov (United States)

    Lafferty, Kevin D.

    2001-01-01

    In order to better understand the nature of disturbances to wintering snowy plovers, I observed snowy plovers and activities that might disturb them at a beach near Devereux Slough in Santa Barbara, California, USA. Disturbance (activity that caused plovers to move or fly) to wintering populations of threatened western snowy plovers was 16 times higher at a public beach than at protected beaches. Wintering plovers reacted to disturbance at half the distance (∼40 m) as has been reported for breeding snowy plovers (∼80 m). Humans, dogs, crows and other birds were the main sources of disturbance on the public beach, and each snowy plover was disturbed, on average, once every 27 weekend min and once every 43 weekday min. Dogs off leash were a disproportionate source of disturbance. Plovers were more likely to fly from dogs, horses and crows than from humans and other shorebirds. Plovers were less abundant near trail heads. Over short time scales, plovers did not acclimate to or successfully find refuge from disturbance. Feeding rates declined with increased human activity. I used data from these observations to parameterize a model that predicted rates of disturbance given various management actions. The model found that prohibiting dogs and a 30 m buffer zone surrounding a 400 m stretch of beach provided the most protection for plovers for the least amount of impact to beach recreation.

  9. Winter chilling speeds spring development of temperate butterflies.

    Science.gov (United States)

    Stålhandske, Sandra; Gotthard, Karl; Leimar, Olof

    2017-07-01

    Understanding and predicting phenology has become more important with ongoing climate change and has brought about great research efforts in the recent decades. The majority of studies examining spring phenology of insects have focussed on the effects of spring temperatures alone. Here we use citizen-collected observation data to show that winter cold duration, in addition to spring temperature, can affect the spring emergence of butterflies. Using spatial mixed models, we disentangle the effects of climate variables and reveal impacts of both spring and winter conditions for five butterfly species that overwinter as pupae across the UK, with data from 1976 to 2013 and one butterfly species in Sweden, with data from 2001 to 2013. Warmer springs lead to earlier emergence in all species and milder winters lead to statistically significant delays in three of the five investigated species. We also find that the delaying effect of winter warmth has become more pronounced in the last decade, during which time winter durations have become shorter. For one of the studied species, Anthocharis cardamines (orange tip butterfly), we also make use of parameters determined from previous experiments on pupal development to model the spring phenology. Using daily temperatures in the UK and Sweden, we show that recent variation in spring temperature corresponds to 10-15 day changes in emergence time over UK and Sweden, whereas variation in winter duration corresponds to 20 days variation in the south of the UK versus only 3 days in the south of Sweden. In summary, we show that short winters delay phenology. The effect is most prominent in areas with particularly mild winters, emphasising the importance of winter for the response of ectothermic animals to climate change. With climate change, these effects may become even stronger and apply also at higher latitudes. © 2017 The Authors. Journal of Animal Ecology © 2017 British Ecological Society.

  10. Petroleum supply monthly

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1995-10-01

    The Petroleum Supply Monthly (PSM) is one of a family of four publications produced by the Petroleum Supply Division within the Energy Information Administration (EIA) reflecting different levels of data timeliness and completeness. The other publications are the Weekly Petroleum Status Report (WPSR), the Winter Fuels Report, and the Petroleum Supply Annual (PSA). Data presented in the PSM describe the supply and disposition of petroleum products in the United States and major US geographic regions. The data series describe production, imports and exports, inter-Petroleum Administration for Defense (PAD) District movements, and inventories by the primary suppliers of petroleum products in the United States (50 States and the District of Columbia). The reporting universe includes those petroleum sectors in primary supply. Included are: petroleum refiners, motor gasoline blends, operators of natural gas processing plants and fractionators, inter-PAD transporters, importers, and major inventory holders of petroleum products and crude oil. When aggregated, the data reported by these sectors approximately represent the consumption of petroleum products in the United States.

  11. Arctic lake physical processes and regimes with implications for winter water availability and management in the national petroleum reserve alaska

    Science.gov (United States)

    Jones, Benjamin M.; Arp, C.D.; Hinkel, Kenneth M.; Beck, R.A.; Schmutz, J.A.; Winston, B.

    2009-01-01

    Lakes are dominant landforms in the National Petroleum Reserve Alaska (NPRA) as well as important social and ecological resources. Of recent importance is the management of these freshwater ecosystems because lakes deeper than maximum ice thickness provide an important and often sole source of liquid water for aquatic biota, villages, and industry during winter. To better understand seasonal and annual hydrodynamics in the context of lake morphometry, we analyzed lakes in two adjacent areas where winter water use is expected to increase in the near future because of industrial expansion. Landsat Thematic Mapper and Enhanced Thematic Mapper Plus imagery acquired between 1985 and 2007 were analyzed and compared with climate data to understand interannual variability. Measured changes in lake area extent varied by 0.6% and were significantly correlated to total precipitation in the preceding 12 months (p photography, bathymetric surveys, water-level monitoring, and lake-ice thickness measurements and growth models were used to better understand seasonal hydrodynamics, surface area-to-volume relations, winter water availability, and more permanent changes related to geomorphic change. Together, these results describe how lakes vary seasonally and annually in two critical areas of the NPRA and provide simple models to help better predict variation in lake-water supply. Our findings suggest that both overestimation and underestimation of actual available winter water volume may occur regularly, and this understanding may help better inform management strategies as future resource use expands in the NPRA. ?? 2008 Springer Science+Business Media, LLC.

  12. Arctic lake physical processes and regimes with implications for winter water availability and management in the National Petroleum Reserve Alaska.

    Science.gov (United States)

    Jones, Benjamin M; Arp, Christopher D; Hinkel, Kenneth M; Beck, Richard A; Schmutz, Joel A; Winston, Barry

    2009-06-01

    Lakes are dominant landforms in the National Petroleum Reserve Alaska (NPRA) as well as important social and ecological resources. Of recent importance is the management of these freshwater ecosystems because lakes deeper than maximum ice thickness provide an important and often sole source of liquid water for aquatic biota, villages, and industry during winter. To better understand seasonal and annual hydrodynamics in the context of lake morphometry, we analyzed lakes in two adjacent areas where winter water use is expected to increase in the near future because of industrial expansion. Landsat Thematic Mapper and Enhanced Thematic Mapper Plus imagery acquired between 1985 and 2007 were analyzed and compared with climate data to understand interannual variability. Measured changes in lake area extent varied by 0.6% and were significantly correlated to total precipitation in the preceding 12 months (p photography, bathymetric surveys, water-level monitoring, and lake-ice thickness measurements and growth models were used to better understand seasonal hydrodynamics, surface area-to-volume relations, winter water availability, and more permanent changes related to geomorphic change. Together, these results describe how lakes vary seasonally and annually in two critical areas of the NPRA and provide simple models to help better predict variation in lake-water supply. Our findings suggest that both overestimation and underestimation of actual available winter water volume may occur regularly, and this understanding may help better inform management strategies as future resource use expands in the NPRA.

  13. Clast mobility within boulder beaches over two winters in Galicia, northwestern Spain

    Science.gov (United States)

    Pérez-Alberti, Augusto; Trenhaile, Alan S.

    2015-11-01

    A micro-drone was used to make low altitude flights over boulder beaches at Laxe Brava and Oia in Galicia, northwestern Spain. Flights were made in July 2012, May 2013, and spring 2014. High resolution digital terrain models and orthophotographs, combined with GIS mapping, were used to monitor changes in the position of thousands of boulders. Maximum storm wave height was higher in the winter of 2013-2014 than in winter 2012-2013, and this was reflected in an increase in the proportion of the boulders that moved in the two winters, from 17% to almost 48% at Laxe Brava, and from 53% to almost 88% at Oia. The greater mobility of the boulders at Oia can be attributed in part to their generally smaller size, although there was considerable overlap between the size of boulders that moved and those that did not move within and between the two beaches. There were mobile boulders in areas up to several metres above the high tidal level on both beaches, and boulder transport in the shore-normal and alongshore directions triggered some changes in the beach profiles, particularly in the middle to upper parts of the beaches. Estimates of threshold transport conditions, scaled to boulder mass, breaker height, and other variables, suggested that all but the very largest boulders on the two beaches should have been mobile, even during the summer months when the waves were much lower than in winter. Model over-prediction can be attributed to a number of factors, including: constraints on movement imposed by surrounding boulders; differences in boulder size and their effect on pivoting angles and on the degree to which boulders are exposed or sheltered from wave impact; and difficulties in assigning appropriate values to model coefficients.

  14. Development of a predictive model for 6 month survival in patients with venous thromboembolism and solid malignancy requiring IVC filter placement.

    Science.gov (United States)

    Huang, Steven Y; Odisio, Bruno C; Sabir, Sharjeel H; Ensor, Joe E; Niekamp, Andrew S; Huynh, Tam T; Kroll, Michael; Gupta, Sanjay

    2017-07-01

    Our purpose was to develop a predictive model for short-term survival (i.e. modeling was used to assess variables associated with 6 month survival following filter placement in patients with VTE and solid malignancy. Significant variables were used to generate a predictive model. 397 patients with solid malignancy received a filter during the study period. Three variables were associated with 6 month survival: (1) serum albumin [hazard ratio (HR) 0.496, P predictive model to estimate 6 month survival with an area under the receiver operating characteristic curve of 0.815, sensitivity of 0.782, and specificity of 0.715. Six month survival in patients with VTE and solid malignancy requiring filter placement can be predicted from three patient variables. Our predictive model could be used to help physicians decide whether a permanent or retrievable filter may be more appropriate as well as to assess the risks and benefits for filter retrieval within the context of survival longevity in patients with cancer.

  15. Robust forecasting with exponential and Holt-Winters smoothing.

    OpenAIRE

    Gelper, SEC Sarah; Fried, R; Croux, C.

    2007-01-01

    Robust versions of the exponential and Holt-Winters smoothing method for forecasting are presented. They are suitable for forecasting univariate time series in presence of outliers. The robust exponential and Holt-Winters smoothing methods are presented as a recursive updating scheme. Both the update equation and the selection of the smoothing parameters are robustied. This robust method is equivalent to a particular form of the robust Kalman lter in a local linear trend model. A simulation s...

  16. Nutritional condition of Pacific Black Brant wintering at the extremes of their range

    Science.gov (United States)

    Mason, D.D.; Barboza, P.S.; Ward, D.H.

    2006-01-01

    Endogenous stores of energy allow birds to survive periods of severe weather and food shortage during winter. We documented changes in lipid, protein, moisture, and ash in body tissues of adult female Pacific Black Brant (Branta bernicla nigricans) and modeled the energetic costs of wintering. Birds were collected at the extremes of their winter range, in Alaska and Baja California, Mexico. Body lipids decreased over winter for birds in Alaska but increased for those in Baja California. Conversely, body protein increased over winter for Brant in Alaska and remained stable for birds in Baja California. Lipid stores likely fuel migration for Brant wintering in Baja California and ensure winter survival for those in Alaska. Increases in body protein may support earlier reproduction for Brant in Alaska. Predicted energy demands were similar between sites during late winter but avenues of expenditure were different. Birds in Baja California spent more energy on lipid synthesis while those in Alaska incurred higher thermoregulatory costs. Estimated daily intake rates of eelgrass were similar between sites in early winter; however, feeding time was more constrained in Alaska because of high tides and short photoperiods. Despite differences in energetic costs and foraging time, Brant wintering at both sites appeared to be in good condition. We suggest that wintering in Alaska may be more advantageous than long-distance migration if winter survival is similar between sites and constraints on foraging time do not impair body condition. ?? The Cooper Ornithological Society 2006.

  17. A home assistance model for dementia: outcome in patients with mild-to-moderate Alzheimer's disease after three months

    Directory of Open Access Journals (Sweden)

    Gabriele Carbone

    2013-03-01

    Full Text Available The treatment of dementias, which are currently incurable pathologies, requires an approach to care that involves both the patients and their families. The effect of alternative interventions, besides the pharmacological approach, therefore warrants evaluation. In this paper, we describe one such intervention, which was provided by our home care team for Alzheimer's Disease. Patients were granted a three-month period of home care assistance, which included physical and cognitive rehabilitation as well as interventions on the home environment and the family, such as psychological support for the main caregivers. The assistance was provided in thrice-weekly sessions, each lasting six hours. Twenty-two patients (age 78.4±6.5 yrs, all of whom had received a diagnosis of probable AD, were enrolled. There was a statistically significant improvement in the NPI score (p = 0.004, Barthel index (p = 0.01, Tinetti's scale (p = 0.013 and CBI score (p = 0.016 at the end of the 3-month treatment period. The patients' caregivers also reported a significant improvement in the physical and social burden at the CBI at the end of the period of home care assistance (p = 0.026 and p = 0.006. In a further evaluation performed 3 months after the end of the treatment period, the beneficial effect previously observed in both patients and caregivers was no longer present.

  18. Comparison of several models for long term monthly average daily insolation on horizontal surfaces and the estimation of horizontal surface insolation for 16 U. S. locations

    Science.gov (United States)

    Goswami, T. K.; Klett, D. E.

    1980-11-01

    Six models for estimating monthly average daily total insolation were compared with rehabilitated measured data for seven U.S. locations. The models compared are those of Bennett, Barbaro, et al., Sabbagh, et al., Reddy, Danashyar, and Swartman and Ogunlade. As a result of the comparison, the Barbaro model was chosen to estimate the insolation for U.S. locations for which the required climatological input data exists but for which no insolation data is available. The model was modified by a constant multiplier and used to generate average daily insolation values for the 16 locations. The results are tabulated for use by solar system designers.

  19. GLDAS CLM Land Surface Model L4 Monthly 1.0 x 1.0 degree V001

    Data.gov (United States)

    National Aeronautics and Space Administration — This data set contains a series of land surface parameters simulated from the Common Land Model (CLM) V2.0 model in the Global Land Data Assimilation System (GLDAS)....

  20. Spectrum of winter dermatoses in rural Yemen.

    Science.gov (United States)

    Al-Kamel, Mohamed A

    2016-05-01

    Surveys that have been carried out to determine the prevalence of skin diseases in rural Yemen are scarce or not available. To investigate the spectrum of winter dermatoses in a rural Yemeni community. A retrospective study was conducted at the dermatology outpatient clinic of the Al-Helal Specialized Hospital (Radaa' district of Al Bayda' Governorate) using data analysis of 700 selected records of patients managed during four months of the 2013-14 winter season. Seven hundred patients with 730 diseases were reported in this study; the major bulk of patients (46.57%) were in the >18-40-year age group, and females outnumbered males. By far, dermatitis, eczematous, and allergic disorders (38.49%) topped the list of the most frequent skin disorders groups, followed by skin infections and infestations (20%) and the pigmentary disorders (13.70%) group. Contact dermatitis (10.68%) was the most prevalent skin disorder, followed by hyperpigmentations (8.77%), acne (8.08%), viral infections (5.75%), atopic dermatitis (5.62%), and parasitic infestations (5.34%). This survey has documented the spectrum of winter dermatoses in a rural Yemeni community but also reflects the pattern of common dermatoses in the whole country. Dermatitis, eczematous, and allergic disorders, skin infections, and pigmentary disorders are the commonest groups. Contact dermatitis is the most prevalent disorder, and leishmaniasis is the most prevalent skin infectious disease. Climate, occupational, social, and environmental factors are the main contributors. Such statistics can form an important basis for community-based health policies. © 2015 The International Society of Dermatology.

  1. Winter survival of Scots pine seedlings under different snow conditions.

    Science.gov (United States)

    Domisch, Timo; Martz, Françoise; Repo, Tapani; Rautio, Pasi

    2017-10-10

    Future climate scenarios predict increased air temperatures and precipitation, particularly at high latitudes, and especially so during winter. Soil temperatures, however, are more difficult to predict, since they depend strongly on the fate of the insulating snow cover. 'Rain-on-snow' events and warm spells during winter can lead to thaw-freeze cycles, compacted snow and ice encasement, as well as local flooding. These adverse conditions could counteract the otherwise positive effects of climatic changes on forest seedling growth. In order to study the effects of different winter and snow conditions on young Scots pine (Pinus sylvestris L.) seedlings, we conducted a laboratory experiment in which 80 1-year-old Scots pine seedlings were distributed between four winter treatments in dasotrons: ambient snow cover (SNOW), compressed snow and ice encasement (ICE), flooded and frozen soil (FLOOD) and no snow (NO SNOW). During the winter treatment period and a 1.5-month simulated spring/early summer phase, we monitored the needle, stem and root biomass of the seedlings, and determined their starch and soluble sugar concentrations. In addition, we assessed the stress experienced by the seedlings by measuring chlorophyll fluorescence, electric impedance and photosynthesis of the previous-year needles. Compared with the SNOW treatment, carbohydrate concentrations were lower in the FLOOD and NO SNOW treatments where the seedlings had almost died before the end of the experiment, presumably due to frost desiccation of aboveground parts during the winter treatments. The seedlings of the ICE treatment showed dead needles and stems only above the snow and ice cover. The results emphasize the importance of an insulating and protecting snow cover for small forest tree seedlings, and that future winters with changed snow patterns might affect the survival of tree seedlings and thus forest productivity. © The Author 2017. Published by Oxford University Press. All rights reserved

  2. Eikenprocessierups doorstaat koude winter goed

    NARCIS (Netherlands)

    Mulder, S.

    2010-01-01

    Eikenprocessierupsen zijn niet gedeerd door de langdurige koude van deze winter. Bij het opensnijden van eipakketjes blijken de rupsjes springlevend naar buiten te komen. Het is nog te vroeg om nu al iets te zeggen over de mogelijke overlast later dit jaar. Dat is afhankelijk van de

  3. Monthly land cover-specific evapotranspiration models derived from global eddy flux measurements and remote sensing data

    Science.gov (United States)

    Yuan Fang; Ge Sun; Peter Caldwell; Steven G. McNulty; Asko Noormets; Jean-Christophe Domec; John King; Zhiqiang Zhang; Xudong Zhang; Guanghui Lin; Guangsheng Zhou; Jingfeng Xiao; Jiquan Chen

    2015-01-01

    Evapotranspiration (ET) is arguably the most uncertain ecohydrologic variable for quantifying watershed water budgets. Although numerous ET and hydrological models exist, accurately predicting the effects of global change on water use and availability remains challenging because of model deficiency and/or a lack of input parameters. The objective of this study was to...

  4. Effect of regular winter swimming on the activity of the sympathoadrenal system before and after a single cold water immersion.

    Science.gov (United States)

    Huttunen, P; Rintamäki, H; Hirvonen, J

    2001-08-01

    This study deals with the adaptation of the sympathoadrenal responses to an acute cold water immersion in ordinary winter swimmers. Hormonal responses were determined at the beginning of the winter swimming period in the autumn and after regular swimming for one and three months. Water temperature in the river was 10 degrees C at the beginning and 4 degrees C after one and three months. The mean duration of the test immersion was 36 s. Plasma catecholamine levels determined before the test immersion decreased with the winter swimming period for one month (NA, p swimming the test immersion to 4 degrees C increased noradrenaline to a similar level than the immersion to 10 degrees C at the beginning. Regularly practiced winter swimming for three months led to diminished catecholamine levels measured immediately after the test immersion (p winter swimming attenuates the catecholamine responses to cold water. Adrenaline responses are also affected by its level prior to the immersion.

  5. The separated polar winter stratopause - A gravity wave driven climatological feature

    Science.gov (United States)

    Hitchman, Matthew H.; Gille, John C.; Rodgers, Clive D.; Brasseur, Guy

    1989-01-01

    An examination of satellite-derived temperatures reveals that the winter polar stratopause is usually elevated and warmer than the adjacent midlatitude stratopause. This separated stratopause occurs in both hemispheres, but is more pronounced and persistent in the southern winter. It descends with time towards spring and exhibits week-to-week variability. Observational diagnostics and results from a two-dimensional model suggest that gravity-wave driving can account for this separated polar stratopause by driving a meridional circulation, with downwelling over the winter pole. In the model, the solar heating pattern induces stronger winter westerlies than summer easterlies, which leads to a stronger gravity-wave-driven circulation in the winter hemisphere. Spherical geometry and the high latitude location of the winter westerly jet combine to yield a concentrated region of downwelling. Model results suggest that descent of the temperature maximum with time is probably caused by wave/mean-flow interaction.

  6. NLDAS VIC Land Surface Model L4 Monthly Climatology 0.125 x 0.125 degree V002

    Data.gov (United States)

    National Aeronautics and Space Administration — Abstract: This data set contains a series of land surface parameters simulated from the VIC land-surface model (LSM) for Phase 2 of the North American Land Data...

  7. NLDAS VIC Land Surface Model L4 Monthly 0.125 x 0.125 degree V002

    Data.gov (United States)

    National Aeronautics and Space Administration — This data set contains a series of land surface parameters simulated from the VIC land-surface model (LSM) for Phase 2 of the North American Land Data Assimilation...

  8. GLDAS Noah Land Surface Model L4 Monthly 1.0 x 1.0 degree V001

    Data.gov (United States)

    National Aeronautics and Space Administration — This data set contains a series of land surface parameters simulated from the Noah 2.7.1 model in the Global Land Data Assimilation System (GLDAS). The data are in...

  9. GLDAS Noah Land Surface Model L4 Monthly 0.25 x 0.25 degree V001

    Data.gov (United States)

    National Aeronautics and Space Administration — This data set contains a series of land surface parameters simulated from the Noah 2.7.1 model in the Global Land Data Assimilation System (GLDAS). The data are in...

  10. GLDAS VIC Land Surface Model L4 Monthly 1.0 x 1.0 degree V001

    Data.gov (United States)

    National Aeronautics and Space Administration — This data set contains a series of land surface parameters simulated from the Variable Infiltration Capacity (VIC) model in the Global Land Data Assimilation System...

  11. GLDAS Mosaic Land Surface Model L4 Monthly 1.0 x 1.0 degree V001

    Data.gov (United States)

    National Aeronautics and Space Administration — This data set contains a series of land surface parameters simulated from the Mosaic model in the Global Land Data Assimilation System (GLDAS). The data are in 1.0...

  12. Discriminant models to estimate the body weight loss after a six-month long diet and exercise-based intervention.

    Science.gov (United States)

    Rojo-Tirado, Miguel A; Benito, Pedro J; Peinado, Ana B; Zapico, Augusto G; Calderón, Franciso J

    2016-01-01

    The main concern of the people who follow a weight loss program is the body weight loss, independently of the body composition. The aim of this study was to create a mathematical model able to discriminate the body weight change based on initial body composition variables. The study included 239 overweight and obese participants (18-50 years; Body Mass Index (BMI)>25 and weight loss, during twenty-four weeks while having 25-30% caloric restriction. Two multivariate discriminant models were performed taking into account the groups below and above the mean body weight change. The discriminant models obtained could discriminate the body weight change with a 65-70% of correct classification. BW, fat-free mass (FFM), and fat mass (FM) were shown to be the most discriminant variables for the discriminant models. People having higher FM and FFM at the beginning of an intervention will lose a greater amount of weight until the end of it.

  13. NLDAS Noah Land Surface Model L4 Monthly 0.125 x 0.125 degree V002

    Data.gov (United States)

    National Aeronautics and Space Administration — This data set contains a series of land surface parameters simulated from the Noah land-surface model (LSM) for Phase 2 of the North American Land Data Assimilation...

  14. NLDAS Mosaic Land Surface Model L4 Monthly 0.125 x 0.125 degree V002

    Data.gov (United States)

    National Aeronautics and Space Administration — This data set contains a series of land surface parameters simulated from the Mosaic land-surface model (LSM) for Phase 2 of the North American Land Data...

  15. Xanthophyll cycle pigment and antioxidant profiles of winter-red (anthocyanic) and winter-green (acyanic) angiosperm evergreen species.

    Science.gov (United States)

    Hughes, Nicole M; Burkey, Kent O; Cavender-Bares, Jeannine; Smith, William K

    2012-03-01

    Leaves of many angiosperm evergreen species change colour from green to red during winter, corresponding with the synthesis of anthocyanin pigments. The ecophysiological function of winter colour change (if any), and why it occurs in some species and not others, are not yet understood. It was hypothesized that anthocyanins play a compensatory photoprotective role in species with limited capacity for energy dissipation. Seasonal xanthophyll pigment content, chlorophyll fluorescence, leaf nitrogen, and low molecular weight antioxidants (LMWA) of five winter-red and five winter-green angiosperm evergreen species were compared. Our results showed no difference in seasonal xanthophyll pigment content (V+A+Z g(-1) leaf dry mass) or LMWA between winter-red and winter-green species, indicating red-leafed species are not deficient in their capacity for non-photochemical energy dissipation via these mechanisms. Winter-red and winter-green species also did not differ in percentage leaf nitrogen, corroborating previous studies showing no difference in seasonal photosynthesis under saturating irradiance. Consistent with a photoprotective function of anthocyanin, winter-red species had significantly lower xanthophyll content per unit chlorophyll and less sustained photoinhibition than winter-green species (i.e. higher pre-dawn F(v)/F(m) and a lower proportion of de-epoxidized xanthophylls retained overnight). Red-leafed species also maintained a higher maximum quantum yield efficiency of PSII at midday (F'(v)/F'(m)) during winter, and showed characteristics of shade acclimation (positive correlation between anthocyanin and chlorophyll content, and negative correlation with chlorophyll a/b). These results suggest that the capacity for photon energy dissipation (photochemical and non-photochemical) is not limited in red-leafed species, and that anthocyanins more likely function as an alternative photoprotective strategy to increased VAZ/Chl during winter.

  16. Prediction model for outcome after low-back surgery: individualized likelihood of complication, hospital readmission, return to work, and 12-month improvement in functional disability.

    Science.gov (United States)

    McGirt, Matthew J; Sivaganesan, Ahilan; Asher, Anthony L; Devin, Clinton J

    2015-12-01

    OBJECT Lumbar spine surgery has been demonstrated to be efficacious for many degenerative spine conditions. However, there is wide variability in outcome after spine surgery at the individual patient level. All stakeholders in spine care will benefit from identification of the unique patient or disease subgroups that are least likely to benefit from surgery, are prone to costly complications, and have increased health care utilization. There remains a large demand for individual patient-level predictive analytics to guide decision support to optimize outcomes at the patient and population levels. METHODS One thousand eight hundred three consecutive patients undergoing spine surgery for various degenerative lumbar diagnoses were prospectively enrolled and followed for 1 year. A comprehensive patient interview and health assessment was performed at baseline and at 3 and 12 months after surgery. All predictive covariates were selected a priori. Eighty percent of the sample was randomly selected for model development, and 20% for model validation. Linear regression was performed with Bayesian model averaging to model 12-month ODI (Oswestry Disability Index). Logistic regression with Bayesian model averaging was used to model likelihood of complications, 30-day readmission, need for inpatient rehabilitation, and return to work. Goodness-of-fit was assessed via R(2) for 12-month ODI and via the c-statistic, area under the receiver operating characteristic curve (AUC), for the categorical endpoints. Discrimination (predictive performance) was assessed, using R(2) for the ODI model and the c-statistic for the categorical endpoint models. Calibration was assessed using a plot of predicted versus observed values for the ODI model and the Hosmer-Lemeshow test for the categorical endpoint models. RESULTS On average, all patient-reported outcomes (PROs) were improved after surgery (ODI baseline vs 12 month: 50.4 vs 29.5%, p work, and 449 (24.5%) experienced an unplanned outcome

  17. A comparison of monthly precipitation point estimates at 6 locations in Iran using integration of soft computing methods and GARCH time series model

    Science.gov (United States)

    Mehdizadeh, Saeid; Behmanesh, Javad; Khalili, Keivan

    2017-11-01

    Precipitation plays an important role in determining the climate of a region. Precise estimation of precipitation is required to manage and plan water resources, as well as other related applications such as hydrology, climatology, meteorology and agriculture. Time series of hydrologic variables such as precipitation are composed of deterministic and stochastic parts. Despite this fact, the stochastic part of the precipitation data is not usually considered in modeling of precipitation process. As an innovation, the present study introduces three new hybrid models by integrating soft computing methods including multivariate adaptive regression splines (MARS), Bayesian networks (BN) and gene expression programming (GEP) with a time series model, namely generalized autoregressive conditional heteroscedasticity (GARCH) for modeling of the monthly precipitation. For this purpose, the deterministic (obtained by soft computing methods) and stochastic (obtained by GARCH time series model) parts are combined with each other. To carry out this research, monthly precipitation data of Babolsar, Bandar Anzali, Gorgan, Ramsar, Tehran and Urmia stations with different climates in Iran were used during the period of 1965-2014. Root mean square error (RMSE), relative root mean square error (RRMSE), mean absolute error (MAE) and determination coefficient (R2) were employed to evaluate the performance of conventional/single MARS, BN and GEP, as well as the proposed MARS-GARCH, BN-GARCH and GEP-GARCH hybrid models. It was found that the proposed novel models are more precise than single MARS, BN and GEP models. Overall, MARS-GARCH and BN-GARCH models yielded better accuracy than GEP-GARCH. The results of the present study confirmed the suitability of proposed methodology for precise modeling of precipitation.

  18. External validation and clinical utility of a prediction model for 6-month mortality in patients undergoing hemodialysis for end-stage kidney disease.

    Science.gov (United States)

    Forzley, Brian; Er, Lee; Chiu, Helen Hl; Djurdjev, Ognjenka; Martinusen, Dan; Carson, Rachel C; Hargrove, Gaylene; Levin, Adeera; Karim, Mohamud

    2018-02-01

    End-stage kidney disease is associated with poor prognosis. Health care professionals must be prepared to address end-of-life issues and identify those at high risk for dying. A 6-month mortality prediction model for patients on dialysis derived in the United States is used but has not been externally validated. We aimed to assess the external validity and clinical utility in an independent cohort in Canada. We examined the performance of the published 6-month mortality prediction model, using discrimination, calibration, and decision curve analyses. Data were derived from a cohort of 374 prevalent dialysis patients in two regions of British Columbia, Canada, which included serum albumin, age, peripheral vascular disease, dementia, and answers to the "the surprise question" ("Would I be surprised if this patient died within the next year?"). The observed mortality in the validation cohort was 11.5% at 6 months. The prediction model had reasonable discrimination (c-stat = 0.70) but poor calibration (calibration-in-the-large = -0.53 (95% confidence interval: -0.88, -0.18); calibration slope = 0.57 (95% confidence interval: 0.31, 0.83)) in our data. Decision curve analysis showed the model only has added value in guiding clinical decision in a small range of threshold probabilities: 8%-20%. Despite reasonable discrimination, the prediction model has poor calibration in this external study cohort; thus, it may have limited clinical utility in settings outside of where it was derived. Decision curve analysis clarifies limitations in clinical utility not apparent by receiver operating characteristic curve analysis. This study highlights the importance of external validation of prediction models prior to routine use in clinical practice.

  19. Mexican Mid-winter Waterfowl Survey

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — The Mexican Mid-winter Waterfowl Survey is a continuation of the annual winter waterfowl survey which is conducted in the United States and Mexico. Since the...

  20. Essential Outdoor Sun Safety Tips for Winter

    Science.gov (United States)

    ... Weekend Warriors expand/collapse Vitamin D Essential Outdoor Sun Safety Tips for Winter Winter sports enthusiasts are ... skiing! Be Mindful of Time Spent in the Sun, Regardless of the Season If possible, ski early ...

  1. Three-Month Study of College Student Disordered Gambling Using the Transtheoretical Model: Findings and Lessons Learned

    Science.gov (United States)

    Martin, Ryan J.; Usdan, Stuart; Turner, Lori

    2012-01-01

    Problem: It has been suggested that gambling-related research more closely examine vulnerable population segments. Research indicates that college students are particularly vulnerable to experiencing disordered gambling behavior. Methods: We examined the gambling behavior and gambling-related Transtheoretical Model (TTM) construct (i.e., stage of…

  2. Winter active bumblebees (Bombus terrestris achieve high foraging rates in urban Britain.

    Directory of Open Access Journals (Sweden)

    Ralph J Stelzer

    Full Text Available BACKGROUND: Foraging bumblebees are normally associated with spring and summer in northern Europe. However, there have been sightings of the bumblebee Bombus terrestris during the warmer winters in recent years in southern England. But what floral resources are they relying upon during winter and how much winter forage can they collect? METHODOLOGY/PRINCIPAL FINDINGS: To test if urban areas in the UK provide a rich foraging niche for bees we set up colonies of B. terrestris in the field during two late winter periods (2005/6 & 2006/7 in London, UK, and measured their foraging performance. Fully automatic radio-frequency identification (RFID technology was used in 2006/7 to enable us to record the complete foraging activity of individually tagged bees. The number of bumblebees present during winter (October 2007 to March 2008 and the main plants they visited were also recorded during transect walks. Queens and workers were observed throughout the winter, suggesting a second generation of bee colonies active during the winter months. Mass flowering shrubs such as Mahonia spp. were identified as important food resources. The foraging experiments showed that bees active during the winter can attain nectar and pollen foraging rates that match, and even surpass, those recorded during summer. CONCLUSIONS/SIGNIFICANCE: B. terrestris in the UK are now able to utilise a rich winter foraging resource in urban parks and gardens that might at present still be under-exploited, opening up the possibility of further changes in pollinator phenology.

  3. Winter active bumblebees (Bombus terrestris) achieve high foraging rates in urban Britain.

    Science.gov (United States)

    Stelzer, Ralph J; Chittka, Lars; Carlton, Marc; Ings, Thomas C

    2010-03-05

    Foraging bumblebees are normally associated with spring and summer in northern Europe. However, there have been sightings of the bumblebee Bombus terrestris during the warmer winters in recent years in southern England. But what floral resources are they relying upon during winter and how much winter forage can they collect? To test if urban areas in the UK provide a rich foraging niche for bees we set up colonies of B. terrestris in the field during two late winter periods (2005/6 & 2006/7) in London, UK, and measured their foraging performance. Fully automatic radio-frequency identification (RFID) technology was used in 2006/7 to enable us to record the complete foraging activity of individually tagged bees. The number of bumblebees present during winter (October 2007 to March 2008) and the main plants they visited were also recorded during transect walks. Queens and workers were observed throughout the winter, suggesting a second generation of bee colonies active during the winter months. Mass flowering shrubs such as Mahonia spp. were identified as important food resources. The foraging experiments showed that bees active during the winter can attain nectar and pollen foraging rates that match, and even surpass, those recorded during summer. B. terrestris in the UK are now able to utilise a rich winter foraging resource in urban parks and gardens that might at present still be under-exploited, opening up the possibility of further changes in pollinator phenology.

  4. A new prediction model for grain yield in Northeast China based on spring North Atlantic Oscillation and late-winter Bering Sea ice cover

    Science.gov (United States)

    Zhou, Mengzi; Wang, Huijun; Huo, Zhiguo

    2017-04-01

    Accurate estimations of grain output in the agriculturally important region of Northeast China are of great strategic significance for guaranteeing food security. New prediction models for maize and rice yields are built in this paper based on the spring North Atlantic Oscillation index and the Bering Sea ice cover index. The year-to-year increment is first forecasted and then the original yield value is obtained by adding the historical yield of the previous year. The multivariate linear prediction model of maize shows good predictive ability, with a low normalized root-mean-square error (NRMSE) of 13.9%, and the simulated yield accounts for 81% of the total variance of the observation. To improve the performance of the multivariate linear model, a combined forecasting model of rice is built by considering the weight of the predictors. The NRMSE of the model is 12.9% and the predicted rice yield explains 71% of the total variance. The corresponding cross-validation test and independent samples test further demonstrate the efficiency of the models. It is inferred that the statistical models established here by applying year-to-year increment approach could make rational prediction for the maize and rice yield in Northeast China before harvest. The present study may shed new light on yield prediction in advance by use of antecedent large-scale climate signals adequately.

  5. Leadership in American Indian Communities: Winter Lessons

    Science.gov (United States)

    Metoyer, Cheryl A.

    2010-01-01

    Winter lessons, or stories told in the winter, were one of the ways in which tribal elders instructed and directed young men and women in the proper ways to assume leadership responsibilities. Winter lessons stressed the appropriate relationship between the leader and the community. The intent was to remember the power and purpose of that…

  6. Bias of atmospheric shortwave absorption in the NCAR Community Climate Models 2 and 3: Comparison with monthly ERBE/GEBA measurements

    Science.gov (United States)

    Zhang, M. H.; Lin, W. Y.; Kiehl, J. T.

    1998-04-01

    A direct comparison is made of collocated shortwave reflection at the top of the atmosphere and insolation at the surface between the National Center for Atmospheric Research Community Climate Models 2 and 3 (CCM2 and CCM3) and monthly Earth Radiation Budget Experiment/Global Energy Balance Archive (ERBE/GEBA) measurements. It is shown that atmospheres in the models are brighter at the top of the atmosphere than ERBE measurements and meanwhile transmit more solar radiation to the surface than GEBA measurements. As a consequence, the models underestimate atmospheric shortwave absorption. The amount of this underestimation is about 20 W m-2 in CCM2 and 17 W m-2 in CCM3. It is emphasized that regardless of whether the bias is in clear sky or in clouds, this underestimation has important implications for the intensity of the hydrological cycle and thus circulation in the models.

  7. Government must act now to prevent looming winter crisis.

    Science.gov (United States)

    2016-08-24

    It may seem odd to be talking about winter pressures now, but there are signs that the next 6-8 months are going to be challenging in the extreme. A report from the RCN and the Royal College of Emergency Medicine suggests that emergency department staff are locked in a cycle of permanent crisis. Add a spell of icy weather into the mix and the NHS could collapse under the strain.

  8. Assessment of the APCC coupled MME suite in predicting the distinctive climate impacts of two flavors of ENSO during boreal winter

    Energy Technology Data Exchange (ETDEWEB)

    Jeong, Hye-In; Lee, Doo Young [APEC Climate Center (APCC), Pusan (Korea, Republic of); Pusan National University, Pusan (Korea, Republic of); Ashok, Karumuri [Indian Institute of Tropical Meteorology, Centre for Climate Change Research, Pune (India); Ahn, Joong-Bae [Pusan National University, Pusan (Korea, Republic of); Lee, June-Yi [University of Hawaii, International Pacific Research Center, Honolulu, HI (United States); Luo, Jing-Jia [Research Institute for Global Change/JAMSTEC, Yokohama (Japan); Schemm, Jae-Kyung E. [NCEP/NOAA Climate Prediction Center, Camp Spring, MD (United States); Hendon, Harry H.; Braganza, Karl [Bureau of Meteorology, Centre for Australian Weather and Climate Research, Melbourne, VIC (Australia); Ham, Yoo-Geun [NASA Goddard Space Flight Center (NASA/GSFC), Global Modeling and Assimilation Office, Greenbelt, MD (United States); Universities Space Research Association, Goddard Earth Sciences Technology and Research Studies and Investigations, Greenbelt, MD (United States)

    2012-07-15

    Forecast skill of the APEC Climate Center (APCC) Multi-Model Ensemble (MME) seasonal forecast system in predicting two main types of El Nino-Southern Oscillation (ENSO), namely canonical (or cold tongue) and Modoki ENSO, and their regional climate impacts is assessed for boreal winter. The APCC MME is constructed by simple composite of ensemble forecasts from five independent coupled ocean-atmosphere climate models. Based on a hindcast set targeting boreal winter prediction for the period 1982-2004, we show that the MME can predict and discern the important differences in the patterns of tropical Pacific sea surface temperature anomaly between the canonical and Modoki ENSO one and four month ahead. Importantly, the four month lead MME beats the persistent forecast. The MME reasonably predicts the distinct impacts of the canonical ENSO, including the strong winter monsoon rainfall over East Asia, the below normal rainfall and above normal temperature over Australia, the anomalously wet conditions across the south and cold conditions over the whole area of USA, and the anomalously dry conditions over South America. However, there are some limitations in capturing its regional impacts, especially, over Australasia and tropical South America at a lead time of one and four months. Nonetheless, forecast skills for rainfall and temperature over East Asia and North America during ENSO Modoki are comparable to or slightly higher than those during canonical ENSO events. (orig.)

  9. Winter to winter recurrence of atmospheric circulation anomalies over East Asia and its impact on winter surface air temperature anomalies.

    Science.gov (United States)

    Zhao, Xia; Yang, Guang

    2017-01-01

    The persistence of atmospheric circulation anomalies over East Asia shows a winter to winter recurrence (WTWR) phenomenon. Seasonal variations in sea level pressure anomalies and surface wind anomalies display significantly different characteristics between WTWR and non-WTWR years. The WTWR years are characterized by the recurrence of both a strong (weak) anomalous Siberian High and an East Asian winter monsoon over two successive winters without persistence through the intervening summer. However, anomalies during the non-WTWR years have the opposite sign between the current and ensuing winters. The WTWR of circulation anomalies contributes to that of surface air temperature anomalies (SATAs), which is useful information for improving seasonal and interannual climate predictions over East Asia and China. In the positive (negative) WTWR years, SATAs are cooler (warmer) over East Asia in two successive winters, but the signs of the SATAs are opposite in the preceding and subsequent winters during the non-WTWR years.

  10. Multimodel probabilistic prediction of 2 m-temperature anomalies on the monthly timescale

    Science.gov (United States)

    Ferrone, Alfonso; Mastrangelo, Daniele; Malguzzi, Piero

    2017-05-01

    The 2 m-temperature anomalies from the reforecasts of the CNR-ISAC and ECMWF monthly prediction systems have been combined in a multimodel super-ensemble. Tercile probability predictions obtained from the multimodel have been constructed using direct model outputs (DMO) and model output statistics (MOS), like logistic and nonhomogeneous Gaussian regression, for the 1990-2010 winter seasons. Verification with ERA-Interim reanalyses indicates that logistic regression gives the best results in terms of ranked probability skill scores (RPSS) and reliability diagrams for low-medium forecast probabilities. Also, it is argued that the logistic regression would not yield further improvements if a larger dataset was used.

  11. 33 CFR 100.109 - Winter Harbor Lobster Boat Race, Winter Harbor, ME.

    Science.gov (United States)

    2010-07-01

    ... 33 Navigation and Navigable Waters 1 2010-07-01 2010-07-01 false Winter Harbor Lobster Boat Race, Winter Harbor, ME. 100.109 Section 100.109 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF... Lobster Boat Race, Winter Harbor, ME. (a) Regulated area. The regulated area includes all waters of Winter...

  12. Inertia gravity waves in the upper troposphere during the MaCWAVE winter campaign. Part II. Radar investigations and modelling studies

    Energy Technology Data Exchange (ETDEWEB)

    Serafimovich, A.; Zuelicke, C.; Hoffmann, P.; Peters, D.; Singer, W. [Leibniz-Inst. fuer Atmosphaerenphysik, Kuehlungsborn (Germany); Dalin, P. [Swedish Inst. of Space Physics, Kiruna (Sweden)

    2006-07-01

    We present an experimental and modelling study of a strong gravity wave event in the upper troposphere/lower stratosphere near the Scandinavian mountain ridge. Continuous VHP radar measurements during the MaCWAVE rocket and ground-based measurement campaign were performed at the Norwegian Andoya rocket range (ARR) near Andenes (69.3 N, 16 E) in January 2003. Detailed gravity wave investigations based on PSU/NCAR fifth-generation mesoscale model (MM5) data have been used for comparison with experimentally obtained results. The model data show the presence of a mountain wave and of an inertia gravity wave generated by a jet streak near the tropopause region. Temporal and spatial dependencies of jet induced inertia gravity waves with dominant observed periods of about 13 h and vertical wavelengths of {proportional_to}4.5-5 km are investigated with wavelet transform applied on radar measurements and model data. The jet induced wave packet is observed to move upstream and downward in the upper troposphere. The model data agree with the experimentally obtained results fairly well. Possible reasons for the observed differences, e.g. in the time of maximum of the wave activity, are discussed. Finally, the vertical fluxes of horizontal momentum are estimated with different methods and provide similar amplitudes. We found indications that the derived positive vertical flux of the horizontal momentum corresponds to the obtained parameters of the jet-induced inertia gravity wave, but only at the periods and heights of the strongest wave activity. (orig.)

  13. Inertia gravity waves in the upper troposphere during the MaCWAVE winter campaign - Part II: Radar investigations and modelling studies

    Science.gov (United States)

    Serafimovich, A.; Zülicke, Ch.; Hoffmann, P.; Peters, D.; Dalin, P.; Singer, W.

    2006-11-01

    We present an experimental and modelling study of a strong gravity wave event in the upper troposphere/lower stratosphere near the Scandinavian mountain ridge. Continuous VHF radar measurements during the MaCWAVE rocket and ground-based measurement campaign were performed at the Norwegian Andoya Rocket Range (ARR) near Andenes (69.3° N, 16° E) in January 2003. Detailed gravity wave investigations based on PSU/NCAR Fifth-Generation Mesoscale Model (MM5) data have been used for comparison with experimentally obtained results. The model data show the presence of a mountain wave and of an inertia gravity wave generated by a jet streak near the tropopause region. Temporal and spatial dependencies of jet induced inertia gravity waves with dominant observed periods of about 13 h and vertical wavelengths of ~4.5-5 km are investigated with wavelet transform applied on radar measurements and model data. The jet induced wave packet is observed to move upstream and downward in the upper troposphere. The model data agree with the experimentally obtained results fairly well. Possible reasons for the observed differences, e.g. in the time of maximum of the wave activity, are discussed. Finally, the vertical fluxes of horizontal momentum are estimated with different methods and provide similar amplitudes. We found indications that the derived positive vertical flux of the horizontal momentum corresponds to the obtained parameters of the jet-induced inertia gravity wave, but only at the periods and heights of the strongest wave activity.

  14. Climate Change Affects Winter Chill for Temperate Fruit and Nut Trees

    OpenAIRE

    Eike Luedeling; Girvetz, Evan H.; Semenov, Mikhail A.; Brown, Patrick H.

    2011-01-01

    BACKGROUND: Temperate fruit and nut trees require adequate winter chill to produce economically viable yields. Global warming has the potential to reduce available winter chill and greatly impact crop yields. METHODOLOGY/PRINCIPAL FINDINGS: We estimated winter chill for two past (1975 and 2000) and 18 future scenarios (mid and end 21st century; 3 Global Climate Models [GCMs]; 3 greenhouse gas emissions [GHG] scenarios). For 4,293 weather stations around the world and GCM projections, Safe Win...

  15. Composite Simulation of Dynamic Water Content and Water Use Efficiency of Winter Wheat

    OpenAIRE

    Wang, Liming

    2014-01-01

    In order to forecast the effect of climate warming on agriculture, ENWATBAL model was used to simulate evapotranspiration of winter wheat due to the change of air temperature and precipitation in the coming decades. The effect of climate warming on winter wheat yield in the future decades was speculated by the past yield and climate data in last decades, and the possible water use efficiency in the future decades was calculated. The results indicate that climate warming would increase winter ...

  16. Sleep and Mood During A Winter in Antarctica

    Science.gov (United States)

    Palinkas, Lawrence A.; Houseal, Matt; Miller, Christopher

    2000-01-01

    Seasonal variations in sleep characteristics and their association with changes in mood were examined in 91 American men and women also who spent the 1991 austral winter at three different research stations in Antarctica. Measures of total hours of sleep over a 24-hr period, duration of longest (i.e.,"nighttime") sleep event, number of sleep events, time of sleep onset, and quality of sleep remained unchanged over the course of the austral winter (March through October). However, exposure to total darkness based on station latitude was significantly associated with total hours of sleep, duration of are longest sleep event, time of sleep onset, and quality of sleep. Reported vigor the previous month was a significant independent predictor of changes in all five sleep measures; previous month's measures of all six POMS subscales were significant independent predictors of sleep quality. Sleep characteristics were significant independent predictors of vigor and confusion the following month; total sleep, longest sleep event, sleep onset and sleep quality were significant independent predictors of tension-anxiety and depression. Changes in mood during the austral winter are preceded by changes in sleep characteristics, but prolonged exposure to the photoperiodicity characteristic of the high latitudes appears to be associated with improved sleep. In turn, mood changes appear to affect certain sleep characteristics, especially sleep quality.

  17. Multifidus Muscle Atrophy Not Observed Following Two-segment Anterior Interbody Fusion: A Rabbit Model Study With a 12-Month Follow-up.

    Science.gov (United States)

    Xu, Wen-Bin; Liu, Jun-Hui; Chen, Zhi-Jun; Fang, Xiang-Qian; Fan, Shun-Wu; Hu, Zhi-Jun

    2017-05-15

    Experimental study evaluated magnetic resonance imaging (MRI) and histologic changes in the multifidus muscle after anterior spinal fusion. To determine the effect of spinal fusion on the multifidus muscle in an anterior rabbit model through the use of MRI and histologic evaluation. Retraction and splitting approach are known to be important factors in postoperative injury and atrophy of the multifidus muscle. The effect and possible mechanism of spinal fusion as an independent factor remains unknown. Thirty-six New Zealand white rabbits were divided into two groups. Animals in the fusion group underwent two-level anterior spinal fusion whereas those in the control group underwent similar surgery without spinal fusion. The status of the multifidus muscle was evaluated with MRI and histological analysis at preoperative, 3 weeks, 6 weeks, 3 months, 6 months, and 12 months postoperatively. All rabbits in the fusion group achieved solid fusion. The mean T1-weighted and T2-weighted signal intensity ratios of gross multifidus to psoas muscles were all approximately 1.0 postoperatively, with no remarkable difference between the groups. The mean lesser diameter of myofibrils in either group did not significantly differ between the preoperative and postoperative specimens. There was no significant fibrotic change or fatty degeneration for either group. Decrease in acetylcholine activity or granular degeneration of the neuromuscular junction were not observed, and normal shape and size were found in nearly all samples at all time points in both groups (P > 0.05). After two-segment anterior spinal fusion, multifidus atrophy was not observed throughout a 12-month follow up. The rabbit model of anterior fusion is better suited to study the effect of fusion alone on the status of the multifidus muscle. 3.

  18. Hibernation in an antarctic fish: on ice for winter.

    Directory of Open Access Journals (Sweden)

    Hamish A Campbell

    Full Text Available Active metabolic suppression in anticipation of winter conditions has been demonstrated in species of mammals, birds, reptiles and amphibians, but not fish. This is because the reduction in metabolic rate in fish is directly proportional to the decrease in water temperature and they appear to be incapable of further suppressing their metabolic rate independently of temperature. However, the Antarctic fish (Notothenia coriiceps is unusual because it undergoes winter metabolic suppression irrespective of water temperature. We assessed the seasonal ecological strategy by monitoring swimming activity, growth, feeding and heart rate (f(H in N. coriiceps as they free-ranged within sub-zero waters. The metabolic rate of wild fish was extrapolated from f(H recordings, from oxygen consumption calibrations established in the laboratory prior to fish release. Throughout the summer months N. coriiceps spent a considerable proportion of its time foraging, resulting in a growth rate (G(w of 0.18 +/- 0.2% day(-1. In contrast, during winter much of the time was spent sedentary within a refuge and fish showed a net loss in G(w (-0.05 +/- 0.05% day(-1. Whilst inactive during winter, N. coriiceps displayed a very low f(H, reduced sensory and motor capabilities, and standard metabolic rate was one third lower than in summer. In a similar manner to other hibernating species, dormancy was interrupted with periodic arousals. These arousals, which lasted a few hours, occurred every 4-12 days. During arousal activity, f(H and metabolism increased to summer levels. This endogenous suppression and activation of metabolic processes, independent of body temperature, demonstrates that N. coriiceps were effectively 'putting themselves on ice' during winter months until food resources improved. This study demonstrates that at least some fish species can enter a dormant state similar to hibernation that is not temperature driven and presumably provides seasonal energetic

  19. Inertia gravity waves in the upper troposphere during the MaCWAVE winter campaign – Part II: Radar investigations and modelling studies

    Directory of Open Access Journals (Sweden)

    A. Serafimovich

    2006-11-01

    Full Text Available We present an experimental and modelling study of a strong gravity wave event in the upper troposphere/lower stratosphere near the Scandinavian mountain ridge. Continuous VHF radar measurements during the MaCWAVE rocket and ground-based measurement campaign were performed at the Norwegian Andoya Rocket Range (ARR near Andenes (69.3° N, 16° E in January 2003. Detailed gravity wave investigations based on PSU/NCAR Fifth-Generation Mesoscale Model (MM5 data have been used for comparison with experimentally obtained results. The model data show the presence of a mountain wave and of an inertia gravity wave generated by a jet streak near the tropopause region. Temporal and spatial dependencies of jet induced inertia gravity waves with dominant observed periods of about 13 h and vertical wavelengths of ~4.5–5 km are investigated with wavelet transform applied on radar measurements and model data. The jet induced wave packet is observed to move upstream and downward in the upper troposphere. The model data agree with the experimentally obtained results fairly well. Possible reasons for the observed differences, e.g. in the time of maximum of the wave activity, are discussed. Finally, the vertical fluxes of horizontal momentum are estimated with different methods and provide similar amplitudes. We found indications that the derived positive vertical flux of the horizontal momentum corresponds to the obtained parameters of the jet-induced inertia gravity wave, but only at the periods and heights of the strongest wave activity.

  20. Mercury in wintering seabirds, an aggravating factor to winter wrecks?

    Science.gov (United States)

    Fort, Jérôme; Lacoue-Labarthe, Thomas; Nguyen, Hanh Linh; Boué, Amélie; Spitz, Jérôme; Bustamante, Paco

    2015-09-15

    Every year, thousands of seabirds are cast ashore and are found dead along the coasts of North America and Western Europe. These massive mortality events called 'winter wrecks' have generally been attributed to harsh climatic conditions and prolonged storms which affect bird energy balance and impact their body condition. Nevertheless, additional stress factors, such as contaminant body burden, could potentially cumulate to energy constraints and actively contribute to winter wrecks. However, the role played by these additional factors in seabird massive winter mortality has received little attention to date. In February/March 2014, an unprecedented seabird wreck occurred along the Atlantic French coasts during which > 43,000 seabirds were found dead. By analyzing mercury (Hg) concentrations in various tissues collected on stranded birds, we tested the hypothesis that Hg played a significant role in this mortality. More specifically, we aimed to (1) describe Hg contamination in wintering seabirds found along the French coasts in 2014, and (2) determine if Hg concentrations measured in some vital organs such as kidney and brain reached toxicity thresholds that could have led to deleterious effects and to an enhanced mortality. We found some of the highest Hg levels ever reported in Atlantic puffins, common guillemots, razorbills and kittiwakes. Measured concentrations ranged from 0.8 to 3.6 μg · g(-1) of dry weight in brain, 1.3 to 7.2 μg · g(-1) in muscle, 2.5 to 13.5 μg · g(-1) in kidney, 2.9 to 18.6 μg · g(-1) in blood and from 3.1 to 19.5 μg · g(-1) in liver. Hg concentrations in liver and brain were generally below the estimated acute toxicity levels. However, kidney concentrations were not different than those measured in the liver, and above levels associated to renal sub-lethal effects, suggesting a potential Hg poisoning. We concluded that although Hg was not directly responsible for the high observed mortality, it has been a major aggravating

  1. Skillful long-range prediction of European and North American winters

    Science.gov (United States)

    Scaife, A. A.; Arribas, A.; Blockley, E.; Brookshaw, A.; Clark, R. T.; Dunstone, N.; Eade, R.; Fereday, D.; Folland, C. K.; Gordon, M.; Hermanson, L.; Knight, J. R.; Lea, D. J.; MacLachlan, C.; Maidens, A.; Martin, M.; Peterson, A. K.; Smith, D.; Vellinga, M.; Wallace, E.; Waters, J.; Williams, A.

    2014-04-01

    Until recently, long-range forecast systems showed only modest levels of skill in predicting surface winter climate around the Atlantic Basin and associated fluctuations in the North Atlantic Oscillation at seasonal lead times. Here we use a new forecast system to assess seasonal predictability of winter North Atlantic climate. We demonstrate that key aspects of European and North American winter climate and the surface North Atlantic Oscillation are highly predictable months ahead. We demonstrate high levels of prediction skill in retrospective forecasts of the surface North Atlantic Oscillation, winter storminess, near-surface temperature, and wind speed, all of which have high value for planning and adaptation to extreme winter conditions. Analysis of forecast ensembles suggests that while useful levels of seasonal forecast skill have now been achieved, key sources of predictability are still only partially represented and there is further untapped predictability.

  2. Skillful long-range prediction of European and North American winters

    Science.gov (United States)

    Eade, R.; Scaife, A. A.; Arribas, A.; Blockley, E.; Brookshaw, A.; Clark, R. T.; Dunstone, N.; Fereday, D.; Folland, C. K.; Gordon, M.; Hermanson, L.; Knight, J.; Lea, D. J.; MacLachlan, C.; Maidens, A. V.; Martin, M.; Peterson, A.; Smith, D.; Vellinga, M.; Wallace, E.; Waters, J.; Williams, A.

    2014-12-01

    Until recently, long-range forecast systems showed only modest levels of skill in predicting surface winter climate around the Atlantic Basin and associated fluctuations in the North Atlantic Oscillation at seasonal lead times. Here we use a new forecast system to assess seasonal predictability of winter North Atlantic climate. We demonstrate that key aspects of European and North American winter climate and the surface North Atlantic Oscillation are highly predictable months ahead. We demonstrate high levels of prediction skill in retrospective forecasts of the surface North Atlantic Oscillation, winter storminess, near-surface temperature, and wind speed, all of which have high value for planning and adaptation to extreme winter conditions. Analysis of forecast ensembles suggests that while useful levels of seasonal forecast skill have now been achieved, key sources of predictability are still only partially represented and there is further untapped predictability.

  3. Reduction of net primary productivity in southern China caused by abnormal low-temperature freezing in winter of 2008 detected by a remote sensing-driven ecosystem model

    Science.gov (United States)

    Ju, W.; Liu, Y.; Zhou, Y.; Zhu, G.

    2011-12-01

    Terrestrial carbon cycle is an important determinant of global climate change and affected by various factors, including climate, CO2 concentration, atmospheric nitrogen deposition and human activities. Extreme weather events can significantly regulate short-term even long-term carbon exchanges between terrestrial ecosystems and the atmosphere. During the period from the middle January to the middle February 2008, Southern China was seriously hit by abnormal low-temperature freezing, which caused serous damages to forests and crops. However, the reduction of net primary productivity (NPP) of terrestrial ecosystems caused by this extremely abnormal weather event has not been quantitatively investigated. In this study, the Boreal Ecosystem Productivity Simulator (BEPS) model was employed to assess the reduction of NPP in Southern China caused by the abnormal low-temperature freezing. Prior to the regional simulation, the BEPS model was validated using measured NPP in different ecosystems, demonstrating the ability of this model to simulate NPP reliably in China. Then, it was forced using meteorological data interpolated from observations of weather stations and leaf area index inversed from MODIS reflectance data to simulate national wide NPP at a 500 m resolution for the period from 2003 to 2008. The departures of NPP in 2008 from the means during 2003-2007 were used as the indicator of NPP reduction caused by the low-temperature freezing. It was found out that NPP in 2008 decreased significantly in forests of Southern China, especially in Guangdong, Fujian, Zhejiang, Guangxi, Jiangxi, and Hunan Provinces, in which the low-temperature freeing was more serious. The annul reduction of NPP was above 150 g C/m^2/yr in these areas. Key words: Net Primary Productivity, low-temperature freezing, BEPS model, MODIS Correspondence author: Weimin Ju Email:juweimin@nju.edu.cn

  4. Strong Costs and Benefits of Winter Acclimatization in Drosophila melanogaster.

    Directory of Open Access Journals (Sweden)

    Mads Fristrup Schou

    Full Text Available Studies on thermal acclimation in insects are often performed on animals acclimated in the laboratory under conditions that are not ecologically relevant. Costs and benefits of acclimation responses under such conditions may not reflect costs and benefits in natural populations subjected to daily and seasonal temperature fluctuations. Here we estimated costs and benefits in thermal tolerance limits in relation to winter acclimatization of Drosophila melanogaster. We sampled flies from a natural habitat during winter in Denmark (field flies and compared heat and cold tolerance of these to that of flies collected from the same natural population, but acclimated to 25 °C or 13 °C in the laboratory (laboratory flies. We further obtained thermal performance curves for egg-to-adult viability of field and laboratory (25 °C flies, to estimate possible cross-generational effects of acclimation. We found much higher cold tolerance and a lowered heat tolerance in field flies compared to laboratory flies reared at 25 °C. Flies reared in the laboratory at 13 °C exhibited the same thermal cost-benefit relations as the winter acclimatized flies. We also found a cost of winter acclimatization in terms of decreased egg-to-adult viability at high temperatures of eggs laid by winter acclimatized flies. Based on our findings we suggest that winter acclimatization in nature can induce strong benefits in terms of increased cold tolerance. These benefits can be reproduced in the laboratory under ecologically relevant rearing and testing conditions, and should be incorporated in species distribution modelling. Winter acclimatization also leads to decreased heat tolerance. This may create a mismatch between acclimation responses and the thermal environment, e.g. if temperatures suddenly increase during spring, under current and expected more variable future climatic conditions.

  5. Strong Costs and Benefits of Winter Acclimatization in Drosophila melanogaster.

    Science.gov (United States)

    Schou, Mads Fristrup; Loeschcke, Volker; Kristensen, Torsten Nygaard

    2015-01-01

    Studies on thermal acclimation in insects are often performed on animals acclimated in the laboratory under conditions that are not ecologically relevant. Costs and benefits of acclimation responses under such conditions may not reflect costs and benefits in natural populations subjected to daily and seasonal temperature fluctuations. Here we estimated costs and benefits in thermal tolerance limits in relation to winter acclimatization of Drosophila melanogaster. We sampled flies from a natural habitat during winter in Denmark (field flies) and compared heat and cold tolerance of these to that of flies collected from the same natural population, but acclimated to 25 °C or 13 °C in the laboratory (laboratory flies). We further obtained thermal performance curves for egg-to-adult viability of field and laboratory (25 °C) flies, to estimate possible cross-generational effects of acclimation. We found much higher cold tolerance and a lowered heat tolerance in field flies compared to laboratory flies reared at 25 °C. Flies reared in the laboratory at 13 °C exhibited the same thermal cost-benefit relations as the winter acclimatized flies. We also found a cost of winter acclimatization in terms of decreased egg-to-adult viability at high temperatures of eggs laid by winter acclimatized flies. Based on our findings we suggest that winter acclimatization in nature can induce strong benefits in terms of increased cold tolerance. These benefits can be reproduced in the laboratory under ecologically relevant rearing and testing conditions, and should be incorporated in species distribution modelling. Winter acclimatization also leads to decreased heat tolerance. This may create a mismatch between acclimation responses and the thermal environment, e.g. if temperatures suddenly increase during spring, under current and expected more variable future climatic conditions.

  6. A Monthly-Step Water Balance Model to Evaluate the Hydrological Effects of Climate Change on a Regional Scale for Irrigation Design

    Science.gov (United States)

    Herceg, A.; Kalicz, P.; Kisfaludi, B.; Gribovszki, Z.

    2016-12-01

    Current and ongoing changes in the climate are typified by a rise in global temperatures. Climate change can have a dramatic impact on the water cycle. The aim of this paper was to develop a model based on Thornthwaite-type monthly water balance estimations. The main goals were to calibrate the model parameters using a remote sensing-based evapotranspiration dataset. The calibrated model was used for projection on the basis of four climate model datasets (remo, dmihirham5, smhirca.bcm, knmiracmo2). The four main projection periods were: 1980-2010, 2010-2040, 2040-2070, and 2070-2100. The advantage of this model is its robust structure. It can be applied if temperature and precipitation time series are available. The key parameter is the water storage capacity of the soil (SOILMAX), which can be calibrated using the actual evapotranspiration data available. If the physical properties of the soil are known, the maximal rooting depth is also projectable. The model can be primarily used at the catchment level or for areas without additional amounts of water from below. For testing the model, a mixed parcel of land that is used as a cornfield near Mosonmagyaróvár and a small, forest-covered catchment near Sopron were successfully used as the datasets. Furthermore, we determined the water stress with the calculation of the relative extractable water (REW), soil water deficit (SWD), and the water stress index (IS).

  7. Mangrove species' responses to winter air temperature extremes in China

    Science.gov (United States)

    Chen, Luzhen; Wang, Wenqing; Li, Qingshun Q.; Zhang, Yihui; Yang, Shengchang; Osland, Michael J.; Huang, Jinliang; Peng, Congjiao

    2017-01-01

    The global distribution and diversity of mangrove forests is greatly influenced by the frequency and intensity of winter air temperature extremes. However, our understanding of how different mangrove species respond to winter temperature extremes has been lacking because extreme freezing and chilling events are, by definition, relatively uncommon and also difficult to replicate experimentally. In this study, we investigated species-specific variation in mangrove responses to winter temperature extremes in China. In 10 sites that span a latitudinal gradient, we quantified species-specific damage and recovery following a chilling event, for mangrove species within and outside of their natural range (i.e., native and non-native species, respectively). To characterize plant stress, we measured tree defoliation and chlorophyll fluorescence approximately one month following the chilling event. To quantify recovery, we measured chlorophyll fluorescence approximately nine months after the chilling event. Our results show high variation in the geographic- and species-specific responses of mangroves to winter temperature extremes. While many species were sensitive to the chilling temperatures (e.g., Bruguiera sexangula and species in the Sonneratia and Rhizophora genera), the temperatures during this event were not cold enough to affect certain species (e.g., Kandelia obovata, Aegiceras corniculatum, Avicennia marina, and Bruguiera gymnorrhiza). As expected, non-native species were less tolerant of winter temperature extremes than native species. Interestingly, tidal inundation modulated the effects of chilling. In comparison with other temperature-controlled mangrove range limits across the world, the mangrove range limit in China is unique due to the combination of the following three factors: (1) Mangrove species diversity is comparatively high; (2) winter air temperature extremes, rather than means, are particularly intense and play an important ecological

  8. Communicating Certainty About Nuclear Winter

    Science.gov (United States)

    Robock, A.

    2013-12-01

    I have been spending much of my time in the past several years trying to warn the world about the continuing danger of nuclear weapons, and that the solution is a rapid reduction in the nuclear arsenal. I feel that a scientist who discovers dangers to society has an ethical duty to issue a warning, even if the danger is so scary that it is hard for people to deal with. The debate about nuclear winter in the 1980s helped to end the nuclear arms race, but the planet still has enough nuclear weapons, even after reductions planned for 2017 under the New START treaty, to produce nuclear winter, with temperatures plunging below freezing in the summer in major agricultural regions, threatening the food supply for most of the planet. New research by myself, Brian Toon, Mike Mills, and colleagues over the past six years has found that a nuclear war between any two countries, such as India and Pakistan, using 50 atom bombs each of the size dropped on Hiroshima could produce climate change unprecedented in recorded human history, and a world food crisis because of the agricultural effects. This is much less than 1% of the current global arsenal. Communicating certainty - what we know for sure - has been much more effective than communicating uncertainty. The limited success I have had has come from persistence and serendipity. The first step was to do the science. We have published peer-reviewed articles in major journals, including Science, Nature, Proceedings of the National Academy of Sciences, Journal of Geophysical Research, Atmospheric Chemistry and Physics, Physics Today, and Climatic Change. But policymakers do not read these journals. Through fairly convoluted circumstances, which will be described in this talk, we were able to get papers published in Scientific American and the Bulletin of Atomic Scientists. I have also published several encyclopedia articles on the subject. As a Lead Author of Chapter 8 (Radiative Forcing) of the recently published Fifth Assessment

  9. Monthly deposition of cadmium in rural and industrial areas of Germany (Bayern, Pfalz, Ruhr district) and its influences upon an agricultural model system

    Energy Technology Data Exchange (ETDEWEB)

    Runkel, K.H.; Payer, H.D.

    1983-02-01

    Monthly depositions of cadmium were collected by a modified Bergerhoff method and measured by AAS during a 3-year period in rural areas of the Pfalz and in an industrial area of the Ruhr district. Another one year period included measurements in rural areas of southern Bavaria and on a Dutch island. The log-normally distributed deposition rates of cadmium at the rural areas in southern Germany amounted to only 20% of those of the industrial district. The depositions on the Dutch island were twice as high as the depositions on the rural areas of southern Germany. The monthly cadmium deposition rates show only little periodical fluctuation during the year and scatter around more or less constant median values of 25 and 120 micrograms . m-2 . month-1 at the rural and industrial areas, respectively. When open air mass cultures of algae were taken as an agricultural model, the organisms, depending on their growth rate, accumulated 0.4-4.0 ppm of cadmium (dry matter based). The course of the cadmium accumulation reflects the deposition rate of the area where the algae were grown. No growth depression of the algae due to cadmium can be observed under the given deposition rates.

  10. Monthly deposition of cadmium in rural and industrial areas of Germany (Bayern, Pfalz, Ruhr district) and its influences upon an agricultural model system.

    Science.gov (United States)

    Runkel, K H; Payer, H D

    1983-02-01

    Monthly depositions of cadmium were collected by a modified Bergerhoff method and measured by AAS during a 3-year period in rural areas of the Pfalz and in an industrial area of the Ruhr district. Another one year period included measurements in rural areas of southern Bavaria and on a Dutch island. The log-normally distributed deposition rates of cadmium at the rural areas in southern Germany amounted to only 20% of those of the industrial district. The depositions on the Dutch island were twice as high as the depositions on the rural areas of southern Germany. The monthly cadmium deposition rates show only little periodical fluctuation during the year and scatter around more or less constant median values of 25 and 120 micrograms . m-2 . month-1 at the rural and industrial areas, respectively. When open air mass cultures of algae were taken as an agricultural model, the organisms, depending on their growth rate, accumulated 0.4-4.0 ppm of cadmium (dry matter based). The course of the cadmium accumulation reflects the deposition rate of the area where the algae were grown. No growth depression of the algae due to cadmium can be observed under the given deposition rates.

  11. Application of the Artificial Neural Network model for prediction of monthly Standardized Precipitation and Evapotranspiration Index using hydrometeorological parameters and climate indices in eastern Australia

    Science.gov (United States)

    Deo, Ravinesh C.; Şahin, Mehmet

    2015-07-01

    The forecasting of drought based on cumulative influence of rainfall, temperature and evaporation is greatly beneficial for mitigating adverse consequences on water-sensitive sectors such as agriculture, ecosystems, wildlife, tourism, recreation, crop health and hydrologic engineering. Predictive models of drought indices help in assessing water scarcity situations, drought identification and severity characterization. In this paper, we tested the feasibility of the Artificial Neural Network (ANN) as a data-driven model for predicting the monthly Standardized Precipitation and Evapotranspiration Index (SPEI) for eight candidate stations in eastern Australia using predictive variable data from 1915 to 2005 (training) and simulated data for the period 2006-2012. The predictive variables were: monthly rainfall totals, mean temperature, minimum temperature, maximum temperature and evapotranspiration, which were supplemented by large-scale climate indices (Southern Oscillation Index, Pacific Decadal Oscillation, Southern Annular Mode and Indian Ocean Dipole) and the Sea Surface Temperatures (Nino 3.0, 3.4 and 4.0). A total of 30 ANN models were developed with 3-layer ANN networks. To determine the best combination of learning algorithms, hidden transfer and output functions of the optimum model, the Levenberg-Marquardt and Broyden-Fletcher-Goldfarb-Shanno (BFGS) quasi-Newton backpropagation algorithms were utilized to train the network, tangent and logarithmic sigmoid equations used as the activation functions and the linear, logarithmic and tangent sigmoid equations used as the output function. The best ANN architecture had 18 input neurons, 43 hidden neurons and 1 output neuron, trained using the Levenberg-Marquardt learning algorithm using tangent sigmoid equation as the activation and output functions. An evaluation of the model performance based on statistical rules yielded time-averaged Coefficient of Determination, Root Mean Squared Error and the Mean Absolute

  12. Investigation of market efficiency and Financial Stability between S&P 500 and London Stock Exchange: Monthly and yearly Forecasting of Time Series Stock Returns using ARMA model

    Science.gov (United States)

    Rounaghi, Mohammad Mahdi; Nassir Zadeh, Farzaneh

    2016-08-01

    We investigated the presence and changes in, long memory features in the returns and volatility dynamics of S&P 500 and London Stock Exchange using ARMA model. Recently, multifractal analysis has been evolved as an important way to explain the complexity of financial markets which can hardly be described by linear methods of efficient market theory. In financial markets, the weak form of the efficient market hypothesis implies that price returns are serially uncorrelated sequences. In other words, prices should follow a random walk behavior. The random walk hypothesis is evaluated against alternatives accommodating either unifractality or multifractality. Several studies find that the return volatility of stocks tends to exhibit long-range dependence, heavy tails, and clustering. Because stochastic processes with self-similarity possess long-range dependence and heavy tails, it has been suggested that self-similar processes be employed to capture these characteristics in return volatility modeling. The present study applies monthly and yearly forecasting of Time Series Stock Returns in S&P 500 and London Stock Exchange using ARMA model. The statistical analysis of S&P 500 shows that the ARMA model for S&P 500 outperforms the London stock exchange and it is capable for predicting medium or long horizons using real known values. The statistical analysis in London Stock Exchange shows that the ARMA model for monthly stock returns outperforms the yearly. ​A comparison between S&P 500 and London Stock Exchange shows that both markets are efficient and have Financial Stability during periods of boom and bust.

  13. A comparison of two classification based approaches for downscaling of monthly PM10 concentrations

    Science.gov (United States)

    Beck, Christoph; Weitnauer, Claudia; Jacobeit, Jucundus

    2013-04-01

    Circulation type classifications may be utilised for the downscaling of local climatic and environmental target variables in different methodological settings. In this contribution we apply and compare two different classification based approaches for downscaling of monthly indices of PM10 concentrations (monthly mean and number of days exceeding a certain threshold) at different stations in Bavaria (Germany) during the period 1979 to 2010. The first approach uses monthly frequencies of circulation types as predictors in multiple linear regression models (stepwise regression) to estimate monthly predictand values (monthly PM10 indices). The second approach utilizes type specific mean values of the target variable - determined for a calibration period - to estimate predictand values in the validation period. Both approaches are run using varying circulation classifications. This comprises different methodological concepts for circulation classification (e.g. threshold based methods, leader algorithms, cluster analysis) and as well different temporal (1-day or multiple day sequences) and spatial domains (synoptic to continental scale). All models are applied to multiple calibration and validation samples and different skill scores (e.g. reduction of variance, Pearson R) are estimated for each of the validation samples in order to quantify model performance. As main preliminary findings we may state that: - the regression based downscaling approach in most cases clearly outperforms the approach that uses type specific mean values (reference forecasting), - best skill is reached in winter (DJF) and spring (MAM), - comparable model skill is reached for the downscaling of monthly means and extremes indicators (number of days exceeding a certain threshold).

  14. Field Investigations of Winter Transmission of Eastern Equine Encephalitis Virus in Florida

    OpenAIRE

    Bingham, Andrea M.; Burkett-Cadena, Nathan D.; HASSAN, HASSAN K.; McClure, Christopher J.W.; Unnasch, Thomas R

    2014-01-01

    Studies investigating winter transmission of Eastern equine encephalitis virus (EEEV) were conducted in Hillsborough County, Florida. The virus was detected in Culiseta melanura and Anopheles quadrimaculatus in February 2012 and 2013, respectively. During the winter months, herons were the most important avian hosts for all mosquito species encountered. In collections carried out in the summer of 2011, blood meals taken from herons were still common, but less frequently encountered than in wi...

  15. The Impact of Winter Heating on Air Pollution in China

    Science.gov (United States)

    Xiao, Qingyang; Ma, Zongwei; Li, Shenshen; Liu, Yang

    2015-01-01

    Fossil-fuel combustion related winter heating has become a major air quality and public health concern in northern China recently. We analyzed the impact of winter heating on aerosol loadings over China using the MODIS-Aqua Collection 6 aerosol product from 2004–2012. Absolute humidity (AH) and planetary boundary layer height (PBL) -adjusted aerosol optical depth (AOD*) was constructed to reflect ground-level PM2.5 concentrations. GIS analysis, standard statistical tests, and statistical modeling indicate that winter heating is an important factor causing increased PM2.5 levels in more than three-quarters of central and eastern China. The heating season AOD* was more than five times higher as the non-heating season AOD*, and the increase in AOD* in the heating areas was greater than in the non-heating areas. Finally, central heating tend to contribute less to air pollution relative to other means of household heating. PMID:25629878

  16. Monthly Meteorological Reports

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Monthly forms that do not fit into any regular submission. Tabulation sheets and generic monthly forms designed to capture miscellaneous monthly observations.

  17. Three-Month Real-Time Dengue Forecast Models: An Early Warning System for Outbreak Alerts and Policy Decision Support in Singapore

    Science.gov (United States)

    Shi, Yuan; Liu, Xu; Kok, Suet-Yheng; Rajarethinam, Jayanthi; Liang, Shaohong; Yap, Grace; Chong, Chee-Seng; Lee, Kim-Sung; Tan, Sharon S.Y.; Chin, Christopher Kuan Yew; Lo, Andrew; Kong, Waiming; Ng, Lee Ching; Cook, Alex R.

    2015-01-01

    Background: With its tropical rainforest climate, rapid urbanization, and changing demography and ecology, Singapore experiences endemic dengue; the last large outbreak in 2013 culminated in 22,170 cases. In the absence of a vaccine on the market, vector control is the key approach for prevention. Objectives: We sought to forecast the evolution of dengue epidemics in Singapore to provide early warning of outbreaks and to facilitate the public health response to moderate an impending outbreak. Methods: We developed a set of statistical models using least absolute shrinkage and selection operator (LASSO) methods to forecast the weekly incidence of dengue notifications over a 3-month time horizon. This forecasting tool used a variety of data streams and was updated weekly, including recent case data, meteorological data, vector surveillance data, and population-based national statistics. The forecasting methodology was compared with alternative approaches that have been proposed to model dengue case data (seasonal autoregressive integrated moving average and step-down linear regression) by fielding them on the 2013 dengue epidemic, the largest on record in Singapore. Results: Operationally useful forecasts were obtained at a 3-month lag using the LASSO-derived models. Based on the mean average percentage error, the LASSO approach provided more accurate forecasts than the other methods we assessed. We demonstrate its utility in Singapore’s dengue control program by providing a forecast of the 2013 outbreak for advance preparation of outbreak response. Conclusions: Statistical models built using machine learning methods such as LASSO have the potential to markedly improve forecasting techniques for recurrent infectious disease outbreaks such as dengue. Citation: Shi Y, Liu X, Kok SY, Rajarethinam J, Liang S, Yap G, Chong CS, Lee KS, Tan SS, Chin CK, Lo A, Kong W, Ng LC, Cook AR. 2016. Three-month real-time dengue forecast models: an early warning system for outbreak

  18. Winter therapy for the accelerators

    CERN Multimedia

    Corinne Pralavorio

    2016-01-01

    Hundreds of people are hard at work during the year-end technical stop as all the accelerators are undergoing maintenance, renovation and upgrade operations in parallel.   The new beam absorber on its way to Point 2 before being lowered into the LHC tunnel for installation. The accelerator teams didn’t waste any time before starting their annual winter rejuvenation programme over the winter. At the end of November, as the LHC ion run was beginning, work got under way on the PS Booster, where operation had already stopped. On 14 December, once the whole complex had been shut down, the technical teams turned their attention to the other injectors and the LHC. The year-end technical stop (YETS) provides an opportunity to carry out maintenance work on equipment and repair any damage as well as to upgrade the machines for the upcoming runs. Numerous work projects are carried out simultaneously, so good coordination is crucial. Marzia Bernardini's team in the Enginee...

  19. Model to Estimate Monthly Time Horizons for Application of DEA in Selection of Stock Portfolio and for Maintenance of the Selected Portfolio

    Directory of Open Access Journals (Sweden)

    José Claudio Isaias

    2015-01-01

    Full Text Available In the selecting of stock portfolios, one type of analysis that has shown good results is Data Envelopment Analysis (DEA. It, however, has been shown to have gaps regarding its estimates of monthly time horizons of data collection for the selection of stock portfolios and of monthly time horizons for the maintenance of a selected portfolio. To better estimate these horizons, this study proposes a model of mathematical programming binary of minimization of square errors. This model is the paper’s main contribution. The model’s results are validated by simulating the estimated annual return indexes of a portfolio that uses both horizons estimated and of other portfolios that do not use these horizons. The simulation shows that portfolios with both horizons estimated have higher indexes, on average 6.99% per year. The hypothesis tests confirm the statistically significant superiority of the results of the proposed mathematical model’s indexes. The model’s indexes are also compared with portfolios that use just one of the horizons estimated; here the indexes of the dual-horizon portfolios outperform the single-horizon portfolios, though with a decrease in percentage of statistically significant superiority.

  20. Regionalization of monthly rainfall erosivity patterns in Switzerland

    Directory of Open Access Journals (Sweden)

    S. Schmidt

    2016-10-01

    Full Text Available One major controlling factor of water erosion is rainfall erosivity, which is quantified as the product of total storm energy and a maximum 30 min intensity (I30. Rainfall erosivity is often expressed as R-factor in soil erosion risk models like the Universal Soil Loss Equation (USLE and its revised version (RUSLE. As rainfall erosivity is closely correlated with rainfall amount and intensity, the rainfall erosivity of Switzerland can be expected to have a regional characteristic and seasonal dynamic throughout the year. This intra-annual variability was mapped by a monthly modeling approach to assess simultaneously spatial and monthly patterns of rainfall erosivity. So far only national seasonal means and regional annual means exist for Switzerland. We used a network of 87 precipitation gauging stations with a 10 min temporal resolution to calculate long-term monthly mean R-factors. Stepwise generalized linear regression (GLM and leave-one-out cross-validation (LOOCV were used to select spatial covariates which explain the spatial and temporal patterns of the R-factor for each month across Switzerland. The monthly R-factor is mapped by summarizing the predicted R-factor of the regression equation and the corresponding residues of the regression, which are interpolated by ordinary kriging (regression–kriging. As spatial covariates, a variety of precipitation indicator data has been included such as snow depths, a combination product of hourly precipitation measurements and radar observations (CombiPrecip, daily Alpine precipitation (EURO4M-APGD, and monthly precipitation sums (RhiresM. Topographic parameters (elevation, slope were also significant explanatory variables for single months. The comparison of the 12 monthly rainfall erosivity maps showed a distinct seasonality with the highest rainfall erosivity in summer (June, July, and August influenced by intense rainfall events. Winter months have the lowest rainfall erosivity. A

  1. Arctic sea ice reduction and European cold winters in CMIP5 climate change experiments

    National Research Council Canada - National Science Library

    Yang, Shuting; Christensen, Jens H

    2012-01-01

    European winter climate and its possible relationship with the Arctic sea ice reduction in the recent past and future as simulated by the models of the Climate Model Intercomparison Project phase 5 (CMIP5...

  2. Effect of anthropogenic aerosol emissions on precipitation in warm conveyor belts in the western North Pacific in winter - a model study with ECHAM6-HAM

    Science.gov (United States)

    Joos, Hanna; Madonna, Erica; Witlox, Kasja; Ferrachat, Sylvaine; Wernli, Heini; Lohmann, Ulrike

    2017-05-01

    While there is a clear impact of aerosol particles on the radiation balance, whether and how aerosol particles influence precipitation is controversial. Here we use the ECHAM6-HAM global climate model coupled to an aerosol module to analyse whether an impact of anthropogenic aerosol particles on the timing and amount of precipitation can be detected in North Pacific warm conveyor belts. Warm conveyor belts are the strongest precipitation-producing airstreams in extratropical cyclones and are identified here with a Lagrangian technique, i.e. by objectively identifying the most strongly ascending trajectories in North Pacific cyclones. These conveyor belts have been identified separately in 10-year ECHAM6-HAM simulations with present-day and pre-industrial aerosol conditions. Then, the evolution of aerosols and cloud properties has been analysed in detail along the identified warm conveyor belt trajectories. The results show that, under present-day conditions, some warm conveyor belt trajectories are strongly polluted (i.e. high concentrations of black carbon and sulfur dioxide) due to horizontal transport from eastern Asia to the oceanic region where warm conveyor belts start their ascent. In these polluted trajectories a weak delay and reduction of precipitation formation occurs compared to clean warm conveyor belt trajectories. However, all warm conveyor belts consist of both polluted and clean trajectories at the time they start their ascent, and the typically more abundant clean trajectories strongly reduce the aerosol impact from the polluted trajectories. The main conclusion then is that the overall amount of precipitation is comparable in pre-industrial conditions, when all warm conveyor belt trajectories are clean, and in present-day conditions, when warm conveyor belts consist of a mixture of clean and polluted trajectories.

  3. Exceptional Arctic warmth of early winter 2016 and attribution to global warming

    Science.gov (United States)

    van Oldenborgh, Geert Jan; Macias-Fauria, Marc; King, Andrew; Uhe, Peter; Philip, Sjoukje; Kew, Sarah; Karoly, David; Otto, Friederike; Allen, Myles; Cullen, Heidi

    2017-04-01

    The dark polar winters usually sport the coldest extremes on Earth, however this winter, the North Pole and the surrounding Arctic region have experienced record high temperatures in November and December, with daily means reaching 15 °C (27 °F) above normal and a November monthly mean that was 13 °C (23 °F) above normal on the pole. November also saw a brief retreat of sea-ice that was virtually unprecedented in nearly 40 years of satellite records, followed by a record low in November sea ice area since 1850. Unlike the Antarctic, Arctic lands are inhabited and their socio-economic systems are greatly affected by the impacts of extreme and unprecedented sea ice dynamics and temperatures, such as for example, the timing of marine mammal migrations, and refreezing rain on snow that prevents reindeer from feeding. Here we report on our multi-method rapid attribution analysis of North Pole November-December temperatures. To quantify the rarity of the event, we computed the November-December averaged temperature around the North Pole (80-90 °N) in the (short but North-pole covering) ERA-interim reanalysis. To put the event in context of natural variability, we use a longer and closely related time series based on the northern most meteorological observations on land (70-80 °N). This allows for a reconstruction of Arctic temperatures back to about 1900. We also perform a multi-method analysis of North Pole temperatures with two sets of climate models: the CMIP5 multi-model ensemble, and a large ensemble of model runs in the so-called Weather@Home project. Physical mechanisms that are responsible for temperature and sea ice variability in the North Pole region are also discussed. The observations and the bias-corrected CMIP5 ensemble point to a return period of about 50 to 200 years in the present climate, i.e., the probability of such an extreme is about 0.5% to 2% every year, with a large uncertainty. The observations show that November-December temperatures

  4. Seeking explanations for recent changes in abundance of wintering Eurasian Wigeon (Anas penelope) in northwest Europe

    DEFF Research Database (Denmark)

    Fox, Anthony David; Dalby, Lars; Christensen, Thomas Kjær

    2016-01-01

    We analysed annual changes in abundance of Eurasian Wigeon (Anas penelope) derived from mid-winter International Waterbird Census data throughout its northwest European flyway since 1988 using log-linear Poisson regression modelling. Increases in abundance in the north and east of the wintering...

  5. Seasonal variation in orthopedic health services utilization in Switzerland: the impact of winter sport tourism.

    Science.gov (United States)

    Matter-Walstra, Klazien; Widmer, Marcel; Busato, André

    2006-03-03

    Climate- or holiday-related seasonality in hospital admission rates is well known for many diseases. However, little research has addressed the impact of tourism on seasonality in admission rates. We therefore investigated the influence of tourism on emergency admission rates in Switzerland, where winter and summer leisure sport activities in large mountain regions can generate orthopedic injuries. Using small area analysis, orthopedic hospital service areas (HSAo) were evaluated for seasonality in emergency admission rates. Winter sport areas were defined using guest bed accommodation rate patterns of guest houses and hotels located above 1000 meters altitude that show clear winter and summer peak seasons. Emergency admissions (years 2000-2002, n = 135'460) of local and nonlocal HSAo residents were evaluated. HSAo were grouped according to their area type (regular or winter sport area) and monthly analyses of admission rates were performed. Of HSAo within the defined winter sport areas 70.8% show a seasonal, summer-winter peak hospital admission rate pattern and only 1 HSAo outside the defined winter sport areas shows such a pattern. Seasonal hospital admission rates in HSAo in winter sport areas can be up to 4 times higher in winter than the intermediate seasons, and they are almost entirely due to admissions of nonlocal residents. These nonlocal residents are in general -and especially in winter- younger than local residents, and nonlocal residents have a shorter length of stay in winter sport than in regular areas. The overall geographic distribution of nonlocal residents admitted for emergencies shows highest rates during the winter as well as the summer in the winter sport areas. Small area analysis using orthopedic hospital service areas is a reliable method for the evaluation of seasonality in hospital admission rates. In Switzerland, HSAo defined as winter sport areas show a clear seasonal fluctuation in admission rates of only nonlocal residents, whereas

  6. A model study of the pollution effects of the first 3 months of the Holuhraun volcanic fissure: comparison with observations and air pollution effects

    Directory of Open Access Journals (Sweden)

    B. M. Steensen

    2016-08-01

    Full Text Available The volcanic fissure at Holuhraun, Iceland started at the end of August 2014 and continued for 6 months to the end of February 2015, with an extensive lava flow onto the Holuhraun plain. This event was associated with large SO2 emissions, amounting up to approximately 4.5 times the daily anthropogenic SO2 emitted from the 28 European Union countries, Norway, Switzerland and Iceland. In this paper we present results from EMEP/MSC-W model simulations to which we added 750 kg s−1 SO2 emissions at the Holuhraun plain from September to November (SON, testing three different emission heights. The three simulated SO2 concentrations, weighted with the OMI (Ozone Monitoring Instrument satellite averaging kernel, are found to be within 30 % of the satellite-observed SO2 column burden. Constraining the SO2 column burden with the satellite data while using the kernel along with the three simulated height distributions of SO2, we estimate that the median of the daily burdens may have been between 13 and 40 kt in the North Atlantic area under investigation. We suggest this to be the uncertainty in the satellite-derived burdens of SO2, mainly due to the unknown vertical distribution of SO2. Surface observations in Europe outside Iceland showed concentration increases up to > 500 µg m−3 SO2 from volcanic plumes passing. Three well identified episodes, where the plume crossed several countries, are compared in detail to surface measurements. For all events, the general timing of the observed concentration peaks compared quite well to the model results. The overall changes to the European SO2 budget due to the volcanic fissure are estimated. Three-monthly wet deposition (SON of SOx in the 28 European Union countries, Norway and Switzerland is found to be more than 30 % higher in the model simulation with Holuhraun emissions compared to a model simulation with no Holuhraun emissions. The largest increases, apart from extreme values on

  7. Growth of winter flounder (Pseudopleuronectes americanus) and smooth flounder (Liopsetta putnami) in heated and unheated water

    Energy Technology Data Exchange (ETDEWEB)

    Hoornbeek, F.K. (Univ. of New Hampshire, Durham); Sawyer, P.J.; Sawyer, E.S.

    1982-07-01

    O-group and I-group winter (Pseudopleuronetes americanus) and smooth (Liopsetta putnami) flounder were reared at the Jackson Estuarine Laboratory, Durham, NH, U.S.A., between November 1975 and June 1976. Both species gained weight approximately three times more rapidly in heated than in unheated water. In unheated water the smallest winter flounder gained, on average, 116% of their body weight per month. Larger O-group winter flounder increased body weight by 55% per month, while comparably sized female and male smooth flounder gained 52% and 28% per month, respectively. I-group female smooth flounder gained 9.5% and male smooth flounder 8.5% per month in heated water. In unheated water increases were 13%, 22%, and 14% per month for O-group winter, female smooth and male smooth flounder, respectively. I-group winter flounder in unheated water gained weight twice as rapidly (9.5%) per month) as I-group female and male smooth flounder (4.0% and 4.5% per month, respectively). Fish were fed a moist diet at a level of 10% of their body weight per day. Conversions (dry weight of food/wet weight of fish) ranged from 1:1 for O-group winter flounder in heated water to 27:1 for I-group smooth flounder in unheated water. Disease was a major cause of mortality. Vibrio anguillarum was confirmed as a pathogen; myxobacteria, and the protozoan parasites Kudoa sp. and Nosema sp. were associated with losses.

  8. Hourly model to estimate solar global radiation for all months of the year for Botucatu, Sao Paulo State; Modelos horarios para estimativa da radiacao solar global para todos os meses do ano para Botucatu-SP

    Energy Technology Data Exchange (ETDEWEB)

    Laperuta Filho, Jayme; Lunardi, Dalva M. Cury [UNESP, Botucatu, SP (Brazil). Faculdade de Ciencias Agronomicas

    1997-12-31

    The objective of this work was establish and daily models for estimate of solar global radiation for the months of the year, in Botucatu-SP 22 deg C 52`S,48 deg C 26`W Grw). The obtention of these models showed be viable high degree of reliability considering that they are specific for hours and months that originated them. The coefficients a and b presented monthly and hourly variations, taking into account that b showed higher relative variability than a. In all months studied, the linear adjustment was not appropriate before 7 a.m and after 5 p.m. (author) 7 refs., 5 tabs.

  9. The majority of sick children receive paracetamol during the winter

    DEFF Research Database (Denmark)

    Ertmann, Ruth Kirk; Møller, Janne Julie; Waldorff, Frans Boch

    2012-01-01

    -administered paracetamol in toddlers during a winter-period in relation to symptoms, doctor contacts and severity-rated illness. MATERIAL AND METHODS: The study was conducted as a prospective diary study covering a three-month winter-period. It comprised a cohort of 183 infants born in February 2001 in a district...... of the capital area in Denmark. RESULTS: According to the parents, a total of 119 toddlers (65%) received paracetamol at least once during the study period; 9.3% of the toddlers received paracetamol for more than ten days. The administration of paracetamol rose as the number of symptoms increased. Paracetamol....... CONCLUSION: The majority of ill toddlers received paracetamol if they had several symptoms. However, paracetamol was administrated in 37% of days with fever. This use of paracetamol seems reasonable as the parents differentiate between degrees of illness and withhold paracetamol until the second day...

  10. Weather daily variation in winter and its effect on behavior and affective states in day-care children

    Science.gov (United States)

    Ciucci, Enrica; Calussi, Pamela; Menesini, Ersilia; Mattei, Alessandra; Petralli, Martina; Orlandini, Simone

    2011-05-01

    This study aimed to analyze the impact of winter weather conditions on young children's behavior and affective states by examining a group of 61 children attending day-care centers in Florence (Italy). Participants were 33 males, 28 females and their 11 teachers. The mean age of the children at the beginning of the observation period was 24.1 months. The day-care teachers observed the children's behavioral and emotional states during the morning before their sleeping time and filled in a questionnaire for each baby five times over a winter period of 3 weeks. Air temperature, relative humidity, air pressure and solar radiation data were collected every 15 min from a weather station located in the city center of Florence. At the same time, air temperature and relative humidity data were collected in the classroom and in the garden of each day-care center. We used multilevel linear models to evaluate the extent to which children's emotional and behavioral states could be predicted by weather conditions, controlling for child characteristics (gender and age). The data showed that relative humidity and solar radiation were the main predictors of the children's emotional and behavioral states. The outdoor humidity had a significant positive effect on frustration, sadness and aggression; solar radiation had a significant negative effect only on sadness, suggesting that a sunny winter day makes children more cheerful. The results are discussed in term of implications for parents and teachers to improve children's ecological environment.

  11. [Palliative care consultation in the ICU : Descriptive analysis of internal medicine intensive care using a mixed model over 12 months].

    Science.gov (United States)

    Lenz, K; Hofmann-Bichler, B; Pihringer, J; Firlinger, F; Pickl, A; Clodi, M

    2017-11-01

    We retrospectively analyzed the data of 56 of 669 critically ill patients admitted to an internal medicine intensive care unit (ICU) with palliative care provided by a palliative care team over the period of 12 months. For delivering palliative care, we used a mixed model-consisting of both integrative and consultative elements. SAPS III severity score in patients with palliative care was 63 ± 15 compared to 50 ± 15 in all critically ill patients. Hospital mortality was 62.5 vs. 16%. After 3 months, 19.6% of patients with palliative care provided by the palliative care team were still alive. In 15 patients curative therapies were discontinued, while there was no further escalation of the therapy in 30 patients. In 47 patients, special help to the relatives was offered. In 13 cases, there was a disagreement between relatives and the ICU team; in 5 cases a family conference was implemented. Two patients wanted extensive intensive care therapy, despite unfavorable prognosis; one patient wished to die. One patient had an advanced directive.

  12. Winter Snowfall Turns an Emerald White

    Science.gov (United States)

    2001-01-01

    Ireland's climate is normally mild due to the nearby Gulf Stream, but the waning days of 2000 saw the Emerald Isle's green fields swathed in an uncommon blanket of white. The contrast between summer and winter is apparent in this pair of images of southwestern Ireland acquired by MISR's vertical-viewing (nadir) camera on August 23, 2000 (left) and December 29, 2000 (right). The corresponding Terra orbit numbers are 3628 and 5492, respectively.The year 2000 brought record-breaking weather to the British Isles. England and Wales experienced the wettest spring and autumn months since 1766. Despite being one of the warmest years in recent history, a cold snap arrived between Christmas and New Year's Day. According to the UK Meteorological Office, the 18 centimeters (7 inches) of snow recorded at Aldergrove, Northern Ireland, on December 27-28 was the deepest daily fall since 1930.Prominent geographical features visible in the MISR images include Galway Bay near the top left. Further south, the mouth of the River Shannon, the largest river in the British Isles, meets the Atlantic Ocean. In the lower portions of the images are the counties of Limerick, Kerry and Cork.MISR was built and is managed by NASA's Jet Propulsion Laboratory, Pasadena, CA, for NASA's Office of Earth Science, Washington, DC. The Terra satellite is managed by NASA's Goddard Space Flight Center, Greenbelt, MD. JPL is a division of the California Institute of Technology

  13. Monthly and diurnal variations of limnological conditions of two ponds

    Directory of Open Access Journals (Sweden)

    AKM Fazlur Rahaman

    2017-06-01

    Full Text Available A study on monthly and diurnal changes of limnological conditions of two ponds was conducted in the Bangladesh Agricultural University campus, Mymensingh. The research work was performed by studying the limnological parameters such as transparency, temperature, dissolved oxygen, free carbon dioxide, pH, total alkalinity, nitrate-nitrogen, phosphate-phosphorus and plankton. Diurnal variations of physico-chemical factors were studied fortnightly at 6 hrs intervals at 6 a.m., 12 noon, 6 p.m. and 12 midnight. The amounts of transparency, dissolved oxygen and pH were higher during winter months than in summer months in both the ponds. Transparency, water temperature, total alkalinity, NO3-N and PO4-P were higher during summer months than in winter months in both the ponds. But the amount of free carbon dioxide was higher during winter months than in summer months in pond 1 while in pond 2 the amount of free carbon dioxide was higher during summer months than in winter months. Qualitative and quantitative monthly variations of phytoplankton and zooplankton were observed in both the ponds during the study period. The highest amount of dissolved oxygen, pH and total alkalinity were recorded at 6 p.m. and the lowest amounts of those at 6 a.m. in both the ponds. The highest temperature was recorded at 12 noon and the lowest at 12 midnight. But the highest amount of free carbon dioxide was recorded at 6 a.m. and the lowest at 6 p.m. in both the ponds. All the factors showed appreciable diel variations throughout the study period, which indicate that the ponds are productive.

  14. Climate change in our backyards: the reshuffling of North America's winter bird communities.

    Science.gov (United States)

    Princé, Karine; Zuckerberg, Benjamin

    2015-02-01

    Much of the recent changes in North American climate have occurred during the winter months, and as result, overwintering birds represent important sentinels of anthropogenic climate change. While there is mounting evidence that bird populations are responding to a warming climate (e.g., poleward shifts) questions remain as to whether these species-specific responses are resulting in community-wide changes. Here, we test the hypothesis that a changing winter climate should favor the formation of winter bird communities dominated by warm-adapted species. To do this, we quantified changes in community composition using a functional index--the Community Temperature Index (CTI)--which measures the balance between low- and high-temperature dwelling species in a community. Using data from Project FeederWatch, an international citizen science program, we quantified spatiotemporal changes in winter bird communities (n = 38 bird species) across eastern North America and tested the influence of changes in winter minimum temperature over a 22-year period. We implemented a jackknife analysis to identify those species most influential in driving changes at the community level and the population dynamics (e.g., extinction or colonization) responsible for these community changes. Since 1990, we found that the winter bird community structure has changed with communities increasingly composed of warm-adapted species. This reshuffling of winter bird communities was strongest in southerly latitudes and driven primarily by local increases in abundance and regional patterns of colonization by southerly birds. CTI tracked patterns of changing winter temperature at different temporal scales ranging from 1 to 35 years. We conclude that a shifting winter climate has provided an opportunity for smaller, southerly distributed species to colonize new regions and promote the formation of unique winter bird assemblages throughout eastern North America. © 2014 John Wiley & Sons Ltd.

  15. The significance of the interception in a Thornthwaite-type monthly step water balance model in context of the climate change

    Science.gov (United States)

    Herceg, András; Kalicz, Péter; Kisfaludi, Balázs

    2017-04-01

    The hydrological impacts of the climate change can be dramatic. Our main purpose is the methodical improvement of a previously established Thornthwaite-type monthly step water balance model, which takes the interception item into account, and compare the results of the evapotranspiration and the soil moisture projections for the 21st century of the original and the upgraded models. Both of the models will be calibrated and validated (using remote-sensed actual evapotranspiration data, called CREMAP) and requires only temperature and precipitation time series as inputs. The projections based on 4 bias-corrected regional climate models databases (FORESEE), and the 3 investigation periods are: 2015-2045, 2045-2075, and 2070-2100. The key parameter is the water storage capacity of the soil, which can be also calibrated using the actual evapotranspiration data. The maximal rooting depth is determinable if the physical properties of the soil are available. The interception can be ranges from 5-40% of gross precipitation, which rate are differing in the various plant communities. Generally, the forests canopy intercepts considerable amounts of rainfall and evaporates back into the atmosphere during and after precipitation event. Leaf area index (LAI) is one of the most significant factor, which determine the canopies storage capacity. Here, MODIS sensor based LAI time series are applied to estimate the storage capacity. A forest covered experimental catchment is utilized for testing the models near to Sopron, Hungary. The projections will expected to demonstrate increasing actual evapotranspiration values, but decreasing trends for the 10 percentile minimum soil moisture values at the end of the 21st century in both model runs. The seasonal periodicity of evapotranspiration may demonstrates the maximums in June or July, while in case of the soil moisture it may shows minimum values in autumn. With the comparison of the two model runs, we expect lower soil water storage

  16. Morphology of the winter anomaly in NmF2 and Total Electron Content

    Science.gov (United States)

    Yasyukevich, Yury; Ratovsky, Konstantin; Yasyukevich, Anna; Klimenko, Maksim; Klimenko, Vladimir; Chirik, Nikolay

    2017-04-01

    We analyzed the winter anomaly manifestation in the F2 peak electron density (NmF2) and Total Electron Content (TEC) based on the observation data and model calculation results. For the analysis we used 1998-2015 TEC Global Ionospheric Maps (GIM) and NmF2 ground-based ionosonde observation data from and COSMIC, CHAMP and GRACE radio occultation data. We used Global Self-consistent Model of the Thermosphere, Ionosphere, and Protonosphere (GSM TIP) and International Reference Ionosphere model (IRI-2012). Based on the observation data and model calculation results we constructed the maps of the winter anomaly intensity in TEC and NmF2 for the different solar and geomagnetic activity levels. The winter anomaly intensity was found to be higher in NmF2 than in TEC according to both observation and modeling. In this report we show the similarity and difference in winter anomaly as revealed in experimental data and model results.

  17. Controls on winter ecosystem respiration in temperate and boreal ecosystems

    Directory of Open Access Journals (Sweden)

    T. Wang

    2011-07-01

    Full Text Available Winter CO2 fluxes represent an important component of the annual carbon budget in northern ecosystems. Understanding winter respiration processes and their responses to climate change is also central to our ability to assess terrestrial carbon cycle and climate feedbacks in the future. However, the factors influencing the spatial and temporal patterns of winter ecosystem respiration (Reco of northern ecosystems are poorly understood. For this reason, we analyzed eddy covariance flux data from 57 ecosystem sites ranging from ~35° N to ~70° N. Deciduous forests were characterized by the highest winter Reco rates (0.90 ± 0.39 g C m−2 d−1, when winter is defined as the period during which daily air temperature remains below 0 °C. By contrast, arctic wetlands had the lowest winter Reco rates (0.02 ± 0.02 g C m−2 d−1. Mixed forests, evergreen needle-leaved forests, grasslands, croplands and boreal wetlands were characterized by intermediate winter Reco rates (g C m−2 d−1 of 0.70(±0.33, 0.60(±0.38, 0.62(±0.43, 0.49(±0.22 and 0.27(±0.08, respectively. Our cross site analysis showed that winter air (Tair and soil (Tsoil temperature played a dominating role in determining the spatial patterns of winter Reco in both forest and managed ecosystems (grasslands and croplands. Besides temperature, the seasonal amplitude of the leaf area index (LAI, inferred from satellite observation, or growing season gross primary productivity, which we use here as a proxy for the amount of recent carbon available for Reco in the subsequent winter, played a marginal role in winter CO2 emissions from forest ecosystems. We found that winter Reco sensitivity to temperature variation across space (

  18. Exploratory Disposal and Reuse Feasibility Analysis of Winter Maintenance Wash Water.

    Science.gov (United States)

    Ullinger, Heather L; Kennedy, Marla J; Schneider, William H; Miller, Christopher M

    2016-01-01

    The Ohio Department of Transportation has more than 60 facilities without sewer access generating approximately 19 million gallons of winter maintenance wash water. Off-site disposal is costly, creating the need for sustainable management strategies. The objective of this study was to conduct an exploratory feasibility analysis to assess wash water disposal and potential reuse as brine. Based on a comprehensive literature review and relevant environmental chemistry, a sampling protocol consisting of 31 water quality constituents was utilized for monthly sampling at three geographically distinct Ohio Department of Transportation garages during the winter of 2012. Results were compared to local disposal and reuse guidance limits. Three constituents, including a maximum copper concentration of 858 ppb, exceeded disposal limits, and many constituents also failed to meet reuse limits. Some concentrations were orders of magnitude higher than reuse limits and suggest pre-treatment would be necessary if wash water were reused as brine. These water quality results, in conjunction with copper chemical equilibrium modeling, show pH and dissolved carbon both significantly impact the total dissolved copper concentration and should be measured to assess reuse potential. The sampling protocol and specific obstacles highlighted in this paper aid in the future development of sustainable wash water management strategies.

  19. Estimation of Genetic Parameters for First Lactation Monthly Test-day Milk Yields using Random Regression Test Day Model in Karan Fries Cattle

    Directory of Open Access Journals (Sweden)

    Ajay Singh

    2016-06-01

    Full Text Available A single trait linear mixed random regression test-day model was applied for the first time for analyzing the first lactation monthly test-day milk yield records in Karan Fries cattle. The test-day milk yield data was modeled using a random regression model (RRM considering different order of Legendre polynomial for the additive genetic effect (4th order and the permanent environmental effect (5th order. Data pertaining to 1,583 lactation records spread over a period of 30 years were recorded and analyzed in the study. The variance component, heritability and genetic correlations among test-day milk yields were estimated using RRM. RRM heritability estimates of test-day milk yield varied from 0.11 to 0.22 in different test-day records. The estimates of genetic correlations between different test-day milk yields ranged 0.01 (test-day 1 [TD-1] and TD-11 to 0.99 (TD-4 and TD-5. The magnitudes of genetic correlations between test-day milk yields decreased as the interval between test-days increased and adjacent test-day had higher correlations. Additive genetic and permanent environment variances were higher for test-day milk yields at both ends of lactation. The residual variance was observed to be lower than the permanent environment variance for all the test-day milk yields.

  20. End-member modeling of the grain-size record of Sikouzi fine sediments in Ningxia (China) and implications for temperature control of Neogene evolution of East Asian winter monsoon

    Science.gov (United States)

    Wan, Shiming; Ma, Xiaolin; Zhong, Ning; Zhao, Debo

    2017-01-01

    The Late Cenozoic East Asian winter monsoon (EAWM) enhancement has been attributed to several factors, such as uplift of the Tibetan Plateau, retreat of the Paratethys Sea, and global cooling related to polar ice volume increment. However, the fundamental forcing factors remain enigmatic due to the absence of long and continuous climate records and sensitive indicators. Here we reanalyzed the published grain-size record of Sikouzi fine sediments in the western Chinese Loess Plateau through end-member (EM) modeling. The results indicate that EM 2 with grain-size peaks between 10–100 μm decreased in content from 20.1 to 17 Ma and stepwise increased from 17 to 0.07 Ma during the following six stages (17–15 Ma, 15–12 Ma, 12–8 Ma, 8–6 Ma, 6–4 Ma and 4–0 Ma). Such varying trends can be successively correlated in seven stages with the integrated benthic δ18O record, implying that global warming weakened the EAWM from 20.1 to 17 Ma and global cooling has stepwise strengthened the EAWM since 17 Ma. Therefore, we conclude that global temperature change played a major role on the evolution of EAWM during the Neogene period. By contrast, Late Cenozoic palaeogeographic reorganization caused by uplift of the Tibetan Plateau and retreat of the Paratethys Sea contributed less to the evolutionary evolution of EAWM. Spectral analysis of the EM 2 data first provided direct evidence of orbitally influenced deposition in the study area and thus the EAWM variations during the Neogene period. The 100-kyr period became weak since ~10 Ma, possibly due to the decrease in sensitivity of a more stable, continental-scale ice sheet in Antarctica to local insolation forcing, deserving further investigation. PMID:29023505

  1. End-member modeling of the grain-size record of Sikouzi fine sediments in Ningxia (China) and implications for temperature control of Neogene evolution of East Asian winter monsoon.

    Science.gov (United States)

    Jiang, Hanchao; Wan, Shiming; Ma, Xiaolin; Zhong, Ning; Zhao, Debo

    2017-01-01

    The Late Cenozoic East Asian winter monsoon (EAWM) enhancement has been attributed to several factors, such as uplift of the Tibetan Plateau, retreat of the Paratethys Sea, and global cooling related to polar ice volume increment. However, the fundamental forcing factors remain enigmatic due to the absence of long and continuous climate records and sensitive indicators. Here we reanalyzed the published grain-size record of Sikouzi fine sediments in the western Chinese Loess Plateau through end-member (EM) modeling. The results indicate that EM 2 with grain-size peaks between 10-100 μm decreased in content from 20.1 to 17 Ma and stepwise increased from 17 to 0.07 Ma during the following six stages (17-15 Ma, 15-12 Ma, 12-8 Ma, 8-6 Ma, 6-4 Ma and 4-0 Ma). Such varying trends can be successively correlated in seven stages with the integrated benthic δ18O record, implying that global warming weakened the EAWM from 20.1 to 17 Ma and global cooling has stepwise strengthened the EAWM since 17 Ma. Therefore, we conclude that global temperature change played a major role on the evolution of EAWM during the Neogene period. By contrast, Late Cenozoic palaeogeographic reorganization caused by uplift of the Tibetan Plateau and retreat of the Paratethys Sea contributed less to the evolutionary evolution of EAWM. Spectral analysis of the EM 2 data first provided direct evidence of orbitally influenced deposition in the study area and thus the EAWM variations during the Neogene period. The 100-kyr period became weak since ~10 Ma, possibly due to the decrease in sensitivity of a more stable, continental-scale ice sheet in Antarctica to local insolation forcing, deserving further investigation.

  2. End-member modeling of the grain-size record of Sikouzi fine sediments in Ningxia (China and implications for temperature control of Neogene evolution of East Asian winter monsoon.

    Directory of Open Access Journals (Sweden)

    Hanchao Jiang

    Full Text Available The Late Cenozoic East Asian winter monsoon (EAWM enhancement has been attributed to several factors, such as uplift of the Tibetan Plateau, retreat of the Paratethys Sea, and global cooling related to polar ice volume increment. However, the fundamental forcing factors remain enigmatic due to the absence of long and continuous climate records and sensitive indicators. Here we reanalyzed the published grain-size record of Sikouzi fine sediments in the western Chinese Loess Plateau through end-member (EM modeling. The results indicate that EM 2 with grain-size peaks between 10-100 μm decreased in content from 20.1 to 17 Ma and stepwise increased from 17 to 0.07 Ma during the following six stages (17-15 Ma, 15-12 Ma, 12-8 Ma, 8-6 Ma, 6-4 Ma and 4-0 Ma. Such varying trends can be successively correlated in seven stages with the integrated benthic δ18O record, implying that global warming weakened the EAWM from 20.1 to 17 Ma and global cooling has stepwise strengthened the EAWM since 17 Ma. Therefore, we conclude that global temperature change played a major role on the evolution of EAWM during the Neogene period. By contrast, Late Cenozoic palaeogeographic reorganization caused by uplift of the Tibetan Plateau and retreat of the Paratethys Sea contributed less to the evolutionary evolution of EAWM. Spectral analysis of the EM 2 data first provided direct evidence of orbitally influenced deposition in the study area and thus the EAWM variations during the Neogene period. The 100-kyr period became weak since ~10 Ma, possibly due to the decrease in sensitivity of a more stable, continental-scale ice sheet in Antarctica to local insolation forcing, deserving further investigation.

  3. [Estimation of Winter Wheat Biomass Using Visible Spectral and BP Based Artificial Neural Networks].

    Science.gov (United States)

    Cui, Ri-xian; Liu, Ya-dong; Fu, Jin-dong

    2015-09-01

    The objective of this study was to evaluate the feasibility of using color digital image analysis and back propagation (BP) based artificial neural networks (ANN) method to estimate above ground biomass at the canopy level of winter wheat field. Digital color images of winter wheat canopies grown under six levels of nitrogen treatments were taken with a digital camera for four times during the elongation stage and at the same time wheat plants were sampled to measure above ground biomass. Canopy cover (CC) and 10 color indices were calculated from winter wheat canopy images by using image analysis program (developed in Microsoft Visual Basic). Correlation analysis was carried out to identify the relationship between CC, 10 color indices and winter wheat above ground biomass. Stepwise multiple linear regression and BP based ANN methods were used to establish the models to estimate winter wheat above ground biomass. The results showed that CC, and two color indices had a significant cor- relation with above ground biomass. CC revealed the highest correlation with winter wheat above ground biomass. Stepwise multiple linear regression model constituting CC and color indices of NDI and b, and BP based ANN model with four variables (CC, g, b and NDI) for input was constructed to estimate winter wheat above ground biomass. The validation results indicate that the model using BP based ANN method has a better performance with higher R2 (0.903) and lower RMSE (61.706) and RRMSE (18.876) in comparation with the stepwise regression model.

  4. A matter of months

    DEFF Research Database (Denmark)

    Frei, Karin Margarita; Villa, Chiara; Jørkov, Marie Louise

    2017-01-01

    , this one-time and one-way movement of an elite female during the possible "age of marriageability" might suggest that she migrated with the aim of establishing an alliance between chiefdoms. Consequently, this detailed multidisciplinary investigation provides a novel tool to reconstruct high resolution......Establishing the age at which prehistoric individuals move away from their childhood residential location holds crucial information about the socio dynamics and mobility patterns in ancient societies. We present a novel combination of strontium isotope analyses performed on the over 3000 year old...... "Skrydstrup Woman" from Denmark, for whom we compiled a highly detailed month-scale model of her migration timeline. When combined with physical anthropological analyses this timeline can be related to the chronological age at which the residential location changed. We conducted a series of high...

  5. Photosynthetic capacity of red spruce during winter

    Science.gov (United States)

    P.G. Schaberg; J.B. Shane; P.F. Cali; J.R. Donnelly; G.R. Strimbeck

    1998-01-01

    We measured the photosynthetic capacity (Pmax) of plantation-grown red spruce (Picea rubens Sarg.) during two winter seasons (1993-94 and 1994-95) and monitored field photosynthesis of these trees during one winter (1993-94). We also measured Pmax for mature montane trees from January through May 1995....

  6. 43 CFR 423.37 - Winter activities.

    Science.gov (United States)

    2010-10-01

    ... 43 Public Lands: Interior 1 2010-10-01 2010-10-01 false Winter activities. 423.37 Section 423.37 Public Lands: Interior Regulations Relating to Public Lands BUREAU OF RECLAMATION, DEPARTMENT OF THE....37 Winter activities. (a) You must not tow persons on skis, sleds, or other sliding devices with a...

  7. 36 CFR 1002.19 - Winter activities.

    Science.gov (United States)

    2010-07-01

    ... 36 Parks, Forests, and Public Property 3 2010-07-01 2010-07-01 false Winter activities. 1002.19... RECREATION § 1002.19 Winter activities. (a) Skiing, snowshoeing, ice skating, sledding, innertubing.... (c) Failure to abide by area designations or activity restrictions established under this section is...

  8. 36 CFR 2.19 - Winter activities.

    Science.gov (United States)

    2010-07-01

    ... 36 Parks, Forests, and Public Property 1 2010-07-01 2010-07-01 false Winter activities. 2.19... RESOURCE PROTECTION, PUBLIC USE AND RECREATION § 2.19 Winter activities. (a) Skiing, snowshoeing, ice... designations or activity restrictions established under this section is prohibited. ...

  9. How to Have a Healthy Winter | Poster

    Science.gov (United States)

    Without a doubt, winter is here. Between the icy weather and the recent hustle and bustle of the holidays, everyone is at an increased risk of getting sick. With that in mind, Occupational Health Services has a few simple tips for staying healthy this winter.

  10. Chapter 7: Migration and winter ecology

    Science.gov (United States)

    Deborah M. Finch; Jeffrey F. Kelly; Jean-Luc E. Cartron

    2000-01-01

    The willow flycatcher (Empidonax traillii) is a Neotropical migrant that breeds in North America, but winters in Central and northern South America. Little specific information is known about migration and wintering ecology of the southwestern willow flycatcher (E. t. extimus) (Yong and Finch 1997). Our report applies principally...

  11. BODY WEIGHT CHARACTERISTICS OF FARM-RAISED FALLOW DEER (DAMA DAMA L. OVER THE WINTER PERIOD

    Directory of Open Access Journals (Sweden)

    P Janiszewski

    2008-11-01

    Full Text Available The aim of this study was to determine the body weight characteristics of fallow deer fawns and does over the period from weaning to the time the animals are put out to pasture, as well as to analyze seasonal variations in their body weights during the winter months. Before the winter the average body weights of fawns, 1.5-year-old does and older does were 24.30 kg, 35.64 kg and 44.60 kg respectively. After the winter the average body weights were as follows: fawns that spent the winter with does in the wintering ground – 22.98 kg, fawns that spent the winter under a shelter – 25.60 kg, does aged 1.5 years – 34.28 kg, does older than 2 years – 42.20 kg. It may be concluded that wintering under a shelter had a positive effect on the body weight gains of fawns.

  12. STUDIES ON THE RESISTANCE TO WINTERING OF THE ITALIAN BEES APIS MELLIFERA LIGUSTICA REARED IN ROMANIA

    Directory of Open Access Journals (Sweden)

    MONICA PÂRVU

    2009-10-01

    Full Text Available The study was conducted on bee families of Apis mellifera carpatica and Apis mellifera ligustica breeds. The bees were housed in multi-storey hives. The experimental period was of 6 months. The resistance to wintering was evaluated on the basis of several apicultural indicators: mortality, feed intake during the winter, general state of the family. Mortality was 35% during wintering for the Carpathian bee and 52% for the Italian bee. The differences were very significant (p≤0.001. When wintering finished all bee families were in good strength. The general state of the bee family was as follows: the Carpathian bee had a strong family when wintering started and ended with a median power; it had a large number of young bees and sufficient reserves; no diarrhoea or mould were noticed; relative humidity was 74%. The Italian bee had a strong family when wintering started and ended with half of the power because of the high mortality during the winter; no diarrhoea or mould were noticed; relative humidity was 69%.

  13. Monthly Weather Review

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Supplements to the Monthly Weather Review publication. The Weather Bureau published the Monthly weather review Supplement irregularly from 1914 to 1949. The...

  14. Atmospheric Simulations Using OGCM-Assimilation SST: Influence of the Wintertime Japan Sea on Monthly Precipitation

    Directory of Open Access Journals (Sweden)

    Masaru Yamamoto Naoki Hirose

    2010-01-01

    Full Text Available Temperature data for the Japan Sea obtained from ocean data assimilation modeling is applied to atmospheric simulations of monthly precipitation for January 2005. Because the volume of flow of the Tsushima Warm Current was large during the winter season, the sea surface temperature (SST and coastal precipitation were higher in comparison with those in 2003. In order to evaluate influence of SST on monthly precipitation, we use surface temperatures of the Japan Sea in 2003 and 2005 for comparative simulations of precipitation for January 2005. The precipitation in experiment C (using cool SST data in 2003 is smaller than that in experiment W (using warm SST data in 2005 in a large part of the sea area, since the small evaporation results from the low SST over the upstream area of northwesterly winter monsoon. In the domain of 33.67 - 45.82°N and 125.89 - 142.9°E, the averaged evaporation and precipitation in experiment C are 10% and 13% smaller than those in experiment W, respectively. About half of the difference between the precipitations observed for January 2003 and 2005 in a heavy snow area is equal to the difference between the two simulations. Our results show that the mesoscale SST difference between 2003 and 2005 is related to the local difference of monthly precipitation.

  15. Field investigations of winter transmission of eastern equine encephalitis virus in Florida.

    Science.gov (United States)

    Bingham, Andrea M; Burkett-Cadena, Nathan D; Hassan, Hassan K; McClure, Christopher J W; Unnasch, Thomas R

    2014-10-01

    Studies investigating winter transmission of Eastern equine encephalitis virus (EEEV) were conducted in Hillsborough County, Florida. The virus was detected in Culiseta melanura and Anopheles quadrimaculatus in February 2012 and 2013, respectively. During the winter months, herons were the most important avian hosts for all mosquito species encountered. In collections carried out in the summer of 2011, blood meals taken from herons were still common, but less frequently encountered than in winter, with an increased frequency of mammalian- and reptile-derived meals observed in the summer. Four wading bird species (Black-crowned Night Heron [Nycticorax nycticorax], Yellow-crowned Night Heron [Nyctanassa violacea], Anhinga [Anhinga anhinga], and Great Blue Heron [Ardea herodias]) were most frequently fed upon by Cs. melanura and Culex erraticus, suggesting that these species may participate in maintaining EEEV during the winter in Florida. © The American Society of Tropical Medicine and Hygiene.

  16. Depletions in winter total ozone values over southern England

    Science.gov (United States)

    Lapworth, A.

    1994-01-01

    A study has been made of the recently re-evaluated time series of daily total ozone values for the period 1979 to 1992 for southern England. The series consists of measurements made at two stations, Bracknell and Camborne. The series shows a steady decline in ozone values in the spring months over the period, and this is consistent with data from an earlier decade that has been published but not re-evaluated. Of exceptional note is the monthly mean for January 1992 which was very significantly reduced from the normal value, and was the lowest so far measured for this month. This winter was also noteworthy for a prolonged period during which a blocking anticyclone dominated the region, and the possibility existed that this was related to the ozone anomaly. It was possible to determine whether the origin of the low ozone value lay in ascending stratospheric motions. A linear regression analysis of ozone value deviation against 100hPa temperature deviations was used to reduce ozone values to those expected in the absence of high pressure. The assumption was made that the normal regression relation was not affected by atmospheric anomalies during the winter. This showed that vertical motions in the stratosphere only accounted for part of the ozone anomaly and that the main cause of the ozone deficit lay either in a reduced stratospheric circulation to which the anticyclone may be related or in chemical effects in the reduced stratospheric temperatures above the high pressure area. A study of the ozone time series adjusted to remove variations correlated with meteorological quantities, showed that during the period since 1979, one other winter, that of 1982/3, showed a similar although less well defined deficit in total ozone values.

  17. Vascular pathology of 20-month-old hypercholesterolemia mice in comparison to triple-transgenic and APPSwDI Alzheimer's disease mouse models.

    Science.gov (United States)

    Hohsfield, Lindsay A; Daschil, Nina; Orädd, Greger; Strömberg, Ingrid; Humpel, Christian

    2014-11-01

    Several studies have shown that elevated plasma cholesterol levels (i.e. hypercholesterolemia) serve as a risk factor for late-onset Alzheimer's disease (AD). However, it remains unclear how hypercholesterolemia may contribute to the onset and progression of AD pathology. In order to determine the role of hypercholesterolemia at various stages of AD, we evaluated the effects of high cholesterol diet (5% cholesterol) in wild-type (WT; C57BL6) and triple-transgenic AD (3xTg-AD; Psen1, APPSwe, tauB301L) mice at 7, 14, and 20 months. The transgenic APP-Swedish/Dutch/Iowa AD mouse model (APPSwDI) was used as a control since these animals are more pathologically-accelerated and are known to exhibit extensive plaque deposition and cerebral amyloid angiopathy. Here, we describe the effects of high cholesterol diet on: (1) cognitive function and stress, (2) AD-associated pathologies, (3) neuroinflammation, (4) blood–brain barrier disruption and ventricle size, and (5) vascular dysfunction. Our data show that high dietary cholesterol increases weight, slightly impairs cognitive function, promotes glial cell activation and complement-related pathways, enhances the infiltration of blood-derived proteins and alters vascular integrity, however, it does not induce AD-related pathologies. While normal-fed 3xTg-AD mice display a typical AD-like pathology in addition to severe cognitive impairment and neuroinflammation at 20 months of age, vascular alterations are less pronounced. No microbleedings were seen by MRI, however, the ventricle size was enlarged. Triple-transgenic AD mice, on the other hand, fed a high cholesterol diet do not survive past 14 months of age. Our data indicates that cholesterol does not markedly potentiate AD-related pathology, nor does it cause significant impairments in cognition. However, it appears that high cholesterol diet markedly increases stress-related plasma corticosterone levels as well as some vessel pathologies. Together, our findings

  18. Combined Use of Landsat-8 and Sentinel-2A Images for Winter Crop Mapping and Winter Wheat Yield Assessment at Regional Scale

    Directory of Open Access Journals (Sweden)

    Sergii Skakun

    2017-05-01

    Full Text Available Timely and accurate information on crop yield and production is critical to many applications within agriculture monitoring. Thanks to its coverage and temporal resolution, coarse spatial resolution satellite imagery has always been a source of valuable information for yield forecasting and assessment at national and regional scales. With availability of free images acquired by Landsat-8 and Sentinel-2 remote sensing satellites, it becomes possible to provide temporal resolution of 3–5 days, and therefore, to develop next generation agriculture products at higher spatial resolution (10–30 m. This paper explores the combined use of Landsat-8 and Sentinel-2A for winter crop mapping and winter wheat yield assessment at regional scale. For the former, we adapt a previously developed approach for the Moderate Resolution Imaging Spectroradiometer (MODIS instrument at 250 m resolution that allows automatic mapping of winter crops taking into account a priori knowledge on crop calendar. For the latter, we use a generalized winter wheat yield forecasting model that is based on estimation of the peak Normalized Difference Vegetation Index (NDVI from MODIS image time-series, and further downscaled to be applicable at 30 m resolution. We show that integration of Landsat-8 and Sentinel-2A improves both winter crop mapping and winter wheat yield assessment. In particular, the error of winter wheat yield estimates can be reduced up to 1.8 times compared to using a single satellite.

  19. Aluminium toxicity in winter wheat

    Directory of Open Access Journals (Sweden)

    Szabó A.

    2015-01-01

    Full Text Available Aluminium is the most frequent metal of the earth crust; it occurs mainly as biologically inactive, insoluble deposit. Environmental problems, industrial contaminations and acid rains increase the soil acidity, leading to the mobilization of Al. Half of the world’s potential arable lands are acidic; therefore, Al-toxicity decreases crop productivity. Wheat is a staple food for 35% of the world population. The effects of Al-stress (0.1 mM were studied on winter wheat; seedlings were grown hydroponically, at acidic pH. After two weeks, the root weight was decreased; a significant difference was found in the P- and Ca-content. The shoot weight and element content changed slightly; Al-content in the root was one magnitude higher than in the shoot, while Al-translocation was limited. The root plasma membrane H+-ATPase has central role in the uptake processes; Al-stress increased the Mg2+-ATPase activity of the microsomal fraction.

  20. New Estimation Rules for Unknown Parameters on Holt-Winters Multiplicative Method

    Directory of Open Access Journals (Sweden)

    Seng Hansun

    2017-09-01

    Full Text Available The Holt-Winters method is a well-known forecasting method used in time-series analysis to forecast future data when a trend and seasonal pattern is detected. There are two variations, i.e. the additive and the multiplicative method. Prior study by Vercher, et al. in [1] has shown that choosing the initial conditions is very important in exponential smoothing models, including the Holt-Winters method. Accurate estimates of initial conditions can result in better forecasting results. In this research, we propose new estimation rules for initial conditions for the Holt-Winters multiplicative method. The estimation rules were derived from the original initial conditions combined with the weighted moving average method. From the experimental results it was found that the new approach of the Holt-Winters multiplicative method can outperform the original Holt-Winters multiplicative method.

  1. FLDAS Noah Land Surface Model L4 Monthly Climatology 0.1 x 0.1 degree for Western Africa (MERRA-2 and CHIRPS) V001 (FLDAS_NOAH01_C_WA_MC) at GES DISC

    Data.gov (United States)

    National Aeronautics and Space Administration — The monthly climatology data set contains a series of land surface parameters simulated from the Noah 3.3 model in the Famine Early Warning Systems Network (FEWS...

  2. FLDAS Noah Land Surface Model L4 Monthly Climatology 0.1 x 0.1 degree for Eastern Africa (MERRA-2 and CHIRPS) V001 (FLDAS_NOAH01_C_EA_MC) at GES DISC

    Data.gov (United States)

    National Aeronautics and Space Administration — The monthly climatology data set contains a series of land surface parameters simulated from the Noah 3.3 model in the Famine Early Warning Systems Network (FEWS...

  3. FLDAS Noah Land Surface Model L4 Monthly Climatology 0.1 x 0.1 degree for Southern Africa (MERRA-2 and CHIRPS) V001 (FLDAS_NOAH01_C_SA_MC) at GES DISC

    Data.gov (United States)

    National Aeronautics and Space Administration — The monthly climatology data set contains a series of land surface parameters simulated from the Noah 3.3 model in the Famine Early Warning Systems Network (FEWS...

  4. Multivariate Regression Analysis of Winter Ozone Events in the Uinta Basin of Eastern Utah, USA

    Science.gov (United States)

    Mansfield, M. L.

    2012-12-01

    I report on a regression analysis of a number of variables that are involved in the formation of winter ozone in the Uinta Basin of Eastern Utah. One goal of the analysis is to develop a mathematical model capable of predicting the daily maximum ozone concentration from values of a number of independent variables. The dependent variable is the daily maximum ozone concentration at a particular site in the basin. Independent variables are (1) daily lapse rate, (2) daily "basin temperature" (defined below), (3) snow cover, (4) midday solar zenith angle, (5) monthly oil production, (6) monthly gas production, and (7) the number of days since the beginning of a multi-day inversion event. Daily maximum temperature and daily snow cover data are available at ten or fifteen different sites throughout the basin. The daily lapse rate is defined operationally as the slope of the linear least-squares fit to the temperature-altitude plot, and the "basin temperature" is defined as the value assumed by the same least-squares line at an altitude of 1400 m. A multi-day inversion event is defined as a set of consecutive days for which the lapse rate remains positive. The standard deviation in the accuracy of the model is about 10 ppb. The model has been combined with historical climate and oil & gas production data to estimate historical ozone levels.

  5. Experimental Winter Coccidiosis in Sheltered and Unsheltered Calves

    Science.gov (United States)

    Niilo, L.

    1970-01-01

    Hereford calves, seven months old, were inoculated orally with sporulated oocysts of Eimeria bovis and E. zurnii and housed in a heated building together with uninoculated animals. Duplicate groups of similarly treated animals were left unsheltered in cold winter weather. Clinical coccidiosis developed in most of the inoculated calves, sheltered and unsheltered. There was no marked difference in the severity of the infections. The sheltered uninoculated contact animals remained clinically unaffected, but mild coccidiosis developed in the unsheltered controls. The results suggest that cold may increase the host's susceptibility to clinical coccidiosis, but may not increase the severity of the signs once the clinical infection is established. PMID:4245999

  6. SU-D-204-05: Fitting Four NTCP Models to Treatment Outcome Data of Salivary Glands Recorded Six Months After Radiation Therapy for Head and Neck Tumors

    Energy Technology Data Exchange (ETDEWEB)

    Mavroidis, P; Price, A; Kostich, M; Green, R; Das, S; Marks, L; Chera, B [University North Carolina, Chapel Hill, NC (United States); Amdur, R; Mendenhall, W [University of Florida, Gainesville, FL (United States); Sheets, N [University of North Carolina, Raleigh, NC (United States)

    2016-06-15

    Purpose: To estimate the radiobiological parameters of four popular NTCP models that describe the dose-response relations of salivary glands to the severity of patient reported dry mouth 6 months post chemo-radiotherapy. To identify the glands, which best correlate with the manifestation of those clinical endpoints. Finally, to evaluate the goodness-of-fit of the NTCP models. Methods: Forty-three patients were treated on a prospective multiinstitutional phase II study for oropharyngeal squamous cell carcinoma. All the patients received 60 Gy IMRT and they reported symptoms using the novel patient reported outcome version of the CTCAE. We derived the individual patient dosimetric data of the parotid and submandibular glands (SMG) as separate structures as well as combinations. The Lyman-Kutcher-Burman (LKB), Relative Seriality (RS), Logit and Relative Logit (RL) NTCP models were used to fit the patients data. The fitting of the different models was assessed through the area under the receiver operating characteristic curve (AUC) and the Odds Ratio methods. Results: The AUC values were highest for the contralateral parotid for Grade ≥ 2 (0.762 for the LKB, RS, Logit and 0.753 for the RL). For the salivary glands the AUC values were: 0.725 for the LKB, RS, Logit and 0.721 for the RL. For the contralateral SMG the AUC values were: 0.721 for LKB, 0.714 for Logit and 0.712 for RS and RL. The Odds Ratio for the contralateral parotid was 5.8 (1.3–25.5) for all the four NTCP models for the radiobiological dose threshold of 21Gy. Conclusion: It was shown that all the examined NTCP models could fit the clinical data well with very similar accuracy. The contralateral parotid gland appears to correlated best with the clinical endpoints of severe/very severe dry mouth. An EQD2Gy dose of 21Gy appears to be a safe threshold to be used as a constraint in treatment planning.

  7. Glucose Content and In Vitro Bioaccessibility in Sweet Potato and Winter Squash Varieties during Storage.

    Science.gov (United States)

    Zaccari, Fernanda; Cabrera, María Cristina; Saadoun, Ali

    2017-06-30

    Glucose content and in vitro bioaccessibility were determined in raw and cooked pulp of Arapey, Cuabé, and Beauregard sweet potato varieties, as well as Maravilla del Mercado and Atlas winter squash, after zero, two, four, and six months of storage (14 °C, 80% relative humidity (RH)). The total glucose content in 100 g of raw pulp was, for Arapey, 17.7 g; Beauregard, 13.2 g; Cuabé, 12.6 g; Atlas, 4.0 g; and in Maravilla del Mercado, 4.1 g. These contents were reduced by cooking process and storage time, 1.1 to 1.5 times, respectively, depending on the sweet potato variety. In winter squash varieties, the total glucose content was not modified by cooking, while the storage increased glucose content 2.8 times in the second month. After in vitro digestion, the glucose content released was 7.0 times higher in sweet potato (6.4 g) than in winter squash (0.91 g) varieties. Glucose released by in vitro digestion for sweet potato stored for six months did not change, but in winter squashes, stored Atlas released glucose content increased 1.6 times. In conclusion, in sweet potato and winter squash, the glucose content and the released glucose during digestive simulation depends on the variety and the storage time. These factors strongly affect the supply of glucose for human nutrition and should be taken into account for adjusting a diet according to consumer needs.

  8. Increasing winter conductive heat transfer in the Arctic sea-ice-covered areas: 1979–2014

    Science.gov (United States)

    Fan, Xieyu; Bi, Haibo; Wang, Yunhe; Fu, Min; Zhou, Xuan; Xu, Xiuli; Huang, Haijun

    2017-12-01

    Sea ice is a quite sensitive indicator in response to regional and global climate changes. Based on monthly mean Pan-Arctic Ice Ocean Modeling and Assimilation System (PIOMAS) sea ice thickness fields, we computed the conductive heat flux (CHF) in the Arctic Ocean in the four winter months (November-February) for a long period of 36 years (1979-2014). The calculated results for each month manifest the increasing extension of the domain with high CHF values since 1979 till 2014. In 2014, regions of roughly 90% of the central Arctic Ocean have been dominated by the CHF values larger than 18 W m-2 (November-December) and 12 W m-2 (January-February), especially significant in the shelf seas around the Arctic Ocean. Moreover, the population distribution frequency (PDF) patterns of the CHF with time show gradually peak shifting toward increased CHF values. The spatiotemporal patterns in terms of the trends in sea ice thickness and other three geophysical parameters, surface air temperature (SAT), sea ice thickness (SIT), and CHF, are well coupled. This suggests that the thinner sea ice cover preconditions for the more oceanic heat loss into atmosphere (as suggested by increased CHF values), which probably contributes to warmer atmosphere which in turn in the long run will cause thinner ice cover. This represents a positive feedback mechanism of which the overall effects would amplify the Arctic climate changes.

  9. Carry-over body mass effect from winter to breeding in a resident seabird, the little penguin.

    Science.gov (United States)

    Salton, Marcus; Saraux, Claire; Dann, Peter; Chiaradia, André

    2015-01-01

    Using body mass and breeding data of individual penguins collected continuously over 7 years (2002-2008), we examined carry-over effects of winter body mass on timing of laying and breeding success in a resident seabird, the little penguin (Eudyptula minor). The austral winter month of July consistently had the lowest rate of colony attendance, which confirmed our expectation that penguins work hard to find resources at this time between breeding seasons. Contrary to our expectation, body mass in winter (July) was equal or higher than in the period before ('moult-recovery') and after ('pre-breeding') in 5 of 7 years for males and in all 7 years for females. We provided evidence of a carry-over effect of body mass from winter to breeding; females and males with higher body mass in winter were more likely to breed early and males with higher body mass in winter were likely to breed successfully. Sex differences might relate to sex-specific breeding tasks, where females may use their winter reserves to invest in egg-laying, whereas males use their winter reserves to sustain the longer fasts ashore during courtship. Our findings suggest that resident seabirds like little penguins can also benefit from a carry-over effect of winter body mass on subsequent breeding.

  10. Contrasting Seasonal Survivorship of Two Migratory Songbirds Wintering in Threatened Mangrove Forests

    Directory of Open Access Journals (Sweden)

    Anna M. Calvert

    2010-06-01

    Full Text Available Long-distance migrants wintering in tropical regions face a number of critical conservation threats throughout their lives, but seasonal estimates of key demographic parameters such as winter survival are rare. Using mist-netting-based mark-recapture data collected in coastal Costa Rica over a six-year period, we examined variation in within- and between-winter survivorship of the Prothonotary Warbler (Protonotaria citrea; 753 young and 376 adults banded, a declining neotropical habitat specialist that depends on threatened mangrove forests during the nonbreeding season. We derived parallel seasonal survivorship estimates for the Northern Waterthrush (Seiurus noveboracensis; 564 young and 93 adults banded, a cohabitant mangrove specialist that has not shown the same population decline in North America, to assess whether contrasting survivorship might contribute to the observed differences in the species' population trajectories. Although average annual survival probability was relatively similar between the two species for both young and adult birds, monthly estimates indicated that relative to Northern Waterthrush, Prothonotary Warblers exhibited: greater interannual variation in survivorship, especially within winters; greater variation in survivorship among the three study sites; lower average between-winter survivorship, particularly among females, and; a sharp decline in between-winter survivorship from 2003 to 2009 for both age groups and both sexes. Rather than identifying one seasonal vital rate as a causal factor of Prothonotary Warbler population declines, our species comparison suggests that the combination of variable within-winter survival with decreasing between-winter survival demands a multi-seasonal approach to the conservation of this and other tropical-wintering migrants.

  11. Prediction of 18-month survival in patients with primary myelodysplastic syndrome. A regression model and scoring system based on the combination of chromosome findings and the Bournemouth score.

    Science.gov (United States)

    Parlier, V; van Melle, G; Beris, P; Schmidt, P M; Tobler, A; Haller, E; Bellomo, M J

    1995-06-01

    The predictive potential of six selected factors was assessed in 72 patients with primary myelodysplastic syndrome using univariate and multivariate logistic regression analysis of survival at 18 months. Factors were age (above median of 69 years), dysplastic features in the three myeloid bone marrow cell lineages, presence of chromosome defects, all metaphases abnormal, double or complex chromosome defects (C23), and a Bournemouth score of 2, 3, or 4 (B234). In the multivariate approach, B234 and C23 proved to be significantly associated with a reduction in the survival probability. The similarity of the regression coefficients associated with these two factors means that they have about the same weight. Consequently, the model was simplified by counting the number of factors (0, 1, or 2) present in each patient, thus generating a scoring system called the Lausanne-Bournemouth score (LB score). The LB score combines the well-recognized and easy-to-use Bournemouth score (B score) with the chromosome defect complexity, C23 constituting an additional indicator of patient outcome. The predicted risk of death within 18 months calculated from the model is as follows: 7.1% (confidence interval: 1.7-24.8) for patients with an LB score of 0, 60.1% (44.7-73.8) for an LB score of 1, and 96.8% (84.5-99.4) for an LB score of 2. The scoring system presented here has several interesting features. The LB score may improve the predictive value of the B score, as it is able to recognize two prognostic groups in the intermediate risk category of patients with B scores of 2 or 3. It has also the ability to identify two distinct prognostic subclasses among RAEB and possibly CMML patients. In addition to its above-described usefulness in the prognostic evaluation, the LB score may bring new insights into the understanding of evolution patterns in MDS. We used the combination of the B score and chromosome complexity to define four classes which may be considered four possible states of

  12. Petroleum supply monthly, October 1993

    Energy Technology Data Exchange (ETDEWEB)

    1993-10-26

    The Petroleum Supply Monthly (PSM) is one of a family of four publications produced by the Petroleum Supply Division within the Energy Information Administration (EIA) reflecting different levels of data timeliness and completeness. The other publications are the Weekly Petroleum Status Report (WPSR), the Winter Fuels Report, and the Petroleum Supply Annual (PSA). Data presented in the PSM describe the supply and disposition of petroleum products in the United States and major US geographic regions. The data series describe production, imports and exports, inter-Petroleum Administration for Defense (PAD) District movements, and inventories by the primary suppliers of petroleum products in the United States (50 States and the District of Columbia). The reporting universe includes those petroleum sectors in primary supply. Included are: petroleum refiners, motor gasoline blenders, operators of natural gas processing plants and fractionators, inter-PAD transporters, importers, and major inventory holders of petroleum products and crude oil. When aggregated, the data reported by these sectors approximately represent the consumption of petroleum products in the United States. Data presented in the PSM are divided into two sections: Summary Statistics and Detailed Statistics.

  13. Petroleum supply monthly, May 1994

    Energy Technology Data Exchange (ETDEWEB)

    1994-05-27

    The Petroleum Supply Monthly (PSM) is one of a family of four publications produced by the Petroleum Supply Division within the Energy Information Administration (EIA) reflecting different levels of data timeliness and completeness. The other publications are the Weekly Petroleum Status Report (WPSR), the Winter Fuels Report, and the Petroleum supply annual (PSA). Data presented in the PSM describe the supply and disposition of petroleum products in the United States and major US geographic regions. The data series describe production, imports and exports, inter-Petroleum Administration for Defense (PAD) District movements, and inventories by the primary suppliers of petroleum products in the United States (50 States and the District of columbia). The reporting universe includes those petroleum sectors in primary supply. Included are: petroleum refiners, motor gasoline blenders, operators of natural gas processing plants and fractionators, inter-PAD transporters, importers, and major inventory holders of petroleum products and crude oil. When aggregated, the data reported by these sectors approximately represent the consumption of petroleum products in the United States. Data presented in the PSM are divided into two sections: Summary Statistics and Detailed Statistics.

  14. Petroleum supply monthly, June 1994

    Energy Technology Data Exchange (ETDEWEB)

    1994-06-28

    The Petroleum Supply Monthly (PSM) is one of a family of four publications produced by the Petroleum Supply Division within the Energy Information Administration (EIA) reflecting different levels of data timeliness and completeness. The other publications are the Weekly Petroleum Status Report (WPSR), the Winter Fuels Report, and the Petroleum Supply Annual (PSA). Data presented in the PSM describe the supply and disposition of petroleum products in the United States and major US geographic regions. The data series describe production, imports and exports, inter-Petroleum Administration for Defense (PAD) District movements, and inventories by the primary suppliers of petroleum products in the United States (50 States and the District of Columbia). The reporting universe includes those petroleum sectors in primary supply. Included are: petroleum refiners, motor gasoline blenders, operators of natural gas processing plants and fractionators, inter-PAD transporters, importers, and major inventory holders of petroleum products and crude oil. When aggregated, the data reported by these sectors approximately represent the consumption of petroleum products in the United States. Data presented in the PSM are divided into two sections: Summary Statistics and Detailed Statistics.

  15. Petroleum supply monthly, January 1996

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1996-02-15

    The Petroleum Supply Monthly (PSM) is one of a family of four publications produced by the Petroleum Supply Division within the Energy Information Administration (EIA) reflecting different levels of data timeliness and completeness. The other publications are the Weekly Petroleum Status Report (WPSR), the Winter Fuels Report, and the Petroleum Supply Annual (PSA). Data presented in the PSM describe the supply and disposition of petroleum products in the United States and major US geographic regions. The data series describe production, imports and exports, inter-Petroleum Administration for Defense (PAD) District movements, and inventories by the primary suppliers of petroleum products in the United States (50 States and the District of Columbia). The reporting universe includes those petroleum sectors in primary supply. Included are: petroleum refiners, motor gasoline blenders, operators of natural gas processing plants and fractionators, inter-PAD transporters, importers, and major inventory holders of petroleum products and crude oil. When aggregated, the data reported by these sectors approximately represent the consumption of petroleum products in the United States. Data presented in the PSM are divided into two sections: Summary Statistics and Detailed Statistics.

  16. A Fleet of Low-Cost Sensor Based Air Quality Monitors Is Used to Measure Carbon Dioxide and Carbon Monoxide in Two Settings: In the Ambient Environment to Explore the Regional-Scale Spatial Variability of These Compounds Via a Distributed Network, and in Homes to Investigate How Heating during Winter Months can Impact Indoor Air Quality.

    Science.gov (United States)

    Casey, J. G.; Hannigan, M.; Collier, A. M.; Coffey, E.; Piedrahita, R.

    2016-12-01

    Affordable, small, portable, quiet tools to measure atmospheric trace gases and air quality enable novel experimental design and new findings. Members of the Hannigan Lab at the University of Colorado in Boulder have been working over the last few years to integrate emerging affordable gas sensors into such an air quality monitor. Presented here are carbon monoxide (CO) and carbon dioxide (CO2) measurements from two field experiments that utilized these tools. In the first experiment, ten air quality monitors were located northeast of Boulder throughout the Denver Julesburg oil and gas basin. The Colorado Department of Health and Environment has several air quality monitoring sites in this broader region, each in an Urban center. One goal of the experiment was to determine whether or not significant spatial variability of EPA criteria pollutants like CO, exists on a sub-regulatory monitoring grid scale. Another goal of the experiment was to compare rural sampling locations with urban sites. The monitors collected continuous data (sampling every 15 seconds) at each location over the course of several months. Our sensor calibration procedures are presented along with our observations and an analysis of the spatial and temporal variability in CO and CO2. In the second experiment, we used eight of our air quality monitors to better understand how home heating fuel type can impact indoor air quality in two communities on the Navajo Nation. We sought to compare air quality in homes using one of four different fuels for heat (wood, wood plus coal, pellet, and gas). There are many factors that contribute to indoor air quality and the impact of an emission source, like a woodstove, within a home. Having multiple, easily deployable, air quality monitors allowed us to account for many of these factors. We sampled four homes at a time, aiming for one home from each of our fuel groups in each sampling period. We sampled inside and outside of each home for a period of 3-4 days

  17. Winter survival of individual honey bees and honey bee colonies depends on level of Varroa destructor infestation.

    Directory of Open Access Journals (Sweden)

    Coby van Dooremalen

    Full Text Available BACKGROUND: Recent elevated winter loss of honey bee colonies is a major concern. The presence of the mite Varroa destructor in colonies places an important pressure on bee health. V. destructor shortens the lifespan of individual bees, while long lifespan during winter is a primary requirement to survive until the next spring. We investigated in two subsequent years the effects of different levels of V. destructor infestation during the transition from short-lived summer bees to long-lived winter bees on the lifespan of individual bees and the survival of bee colonies during winter. Colonies treated earlier in the season to reduce V. destructor infestation during the development of winter bees were expected to have longer bee lifespan and higher colony survival after winter. METHODOLOGY/PRINCIPAL FINDINGS: Mite infestation was reduced using acaricide treatments during different months (July, August, September, or not treated. We found that the number of capped brood cells decreased drastically between August and November, while at the same time, the lifespan of the bees (marked cohorts increased indicating the transition to winter bees. Low V. destructor infestation levels before and during the transition to winter bees resulted in an increase in lifespan of bees and higher colony survival compared to colonies that were not treated and that had higher infestation levels. A variety of stress-related factors could have contributed to the variation in longevity and winter survival that we found between years. CONCLUSIONS/SIGNIFICANCE: This study contributes to theory about the multiple causes for the recent elevated colony losses in honey bees. Our study shows the correlation between long lifespan of winter bees and colony loss in spring. Moreover, we show that colonies treated earlier in the season had reduced V. destructor infestation during the development of winter bees resulting in longer bee lifespan and higher colony survival after winter.

  18. Army Communicator. Volume 36, Number 4, Winter 2011

    Science.gov (United States)

    2011-01-01

    knowledge and accelerate learning as units and personnel rotate in and out of theaters or organizations.” Army leaders realized that “without...QuickScan 20 Winter - 2011 The Future Signal Corps Leaders are the critical element in the network By MAJ Jay H. Anson This article uses the Kotter ...Spoth, 2010). Had the two Services collaborated on their unmanned aerial system programs, the DOD would Applying the Kotter Change Model in shaping

  19. Error analysis for Winters' Additive Seasonal Forecasting System

    OpenAIRE

    McKenzie, Edward

    1984-01-01

    A procedure for deriving the variance of the forecast error for Winters' Additive Seasonal Forecasting system is given. Both point and cumulative T-step ahead forecasts are dealt with. Closed form expressions are given in the cases when the model is (i) trend-free and (ii) non-seasonal. The effects of renormal ization of the seasonal factors is also discussed. The fact that the error variance for this system can be infinite is discussed and the relationship of this property ...

  20. Natural gas monthly

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1998-01-01

    The Natural Gas Monthly highlights activities, events, and analyses of interest to public and private sector organizations associated with the natural gas industry. Volume and price data are presented each month for natural gas production, distribution, consumption, and interstate pipeline activities. Producer-related activities and underground storage data are also reported. From time to time, the Natural Gas Monthly features articles designed to assist readers in using and interpreting natural gas information.

  1. Larix decidua δ18O tree-ring cellulose mainly reflects the isotopic signature of winter snow in a high-altitude glacial valley of the European Alps.

    Science.gov (United States)

    Leonelli, Giovanni; Battipaglia, Giovanna; Cherubini, Paolo; Saurer, Matthias; Siegwolf, Rolf T W; Maugeri, Maurizio; Stenni, Barbara; Fusco, Stella; Maggi, Valter; Pelfini, Manuela

    2017-02-01

    We analyzed the chronologies of cellulose stable isotopes (δ13C and δ18O) and tree-ring widths from European larch (Larix decidua) in a high-altitude site (2190ma.s.l.) at the bottom of a glacial valley in the Italian Alps, and investigated their dependence on monthly meteorological variables and δ18O precipitation values. The δ18O of tree-ring cellulose appears to be strongly driven by the δ18O of winter snowfall (November to March), which suggests that larch trees mostly use the snow-melt water of the previous winter during the growing season. This water, which also comes from the slope streams and from the underground flow of nearby steep slopes, infiltrates the soil in the valley bottom. The tree-ring cellulose δ18O values were also found to be influenced by the August precipitation δ18O and mean temperature. The associated regression model shows that the δ18O chronology from the tree rings explains up to 34% of the variance in the winter precipitation δ18O record, demonstrating the potential for reconstructing the δ18O isotopic composition of past winter precipitation in the study region. Unlike most other tree-ring studies that focus on growing season signals, in our study the summer signal was small and the winter signal dominant due to the special conditions of the glacial valley. Site topography, geomorphology and soil characteristics in particular influence the stable isotope signal in tree-ring cellulose. Copyright © 2016 Elsevier B.V. All rights reserved.

  2. Winter fidelity and apparent survival of lesser snow goose populations in the Pacific flyway

    Science.gov (United States)

    Williams, C.K.; Samuel, M.D.; Baranyuk, Vasily V.; Cooch, E.G.; Kraege, Donald K.

    2008-01-01

    The Beringia region of the Arctic contains 2 colonies of lesser snow geese (Chen caerulescens caerulescens) breeding on Wrangel Island, Russia, and Banks Island, Canada, and wintering in North America. The Wrangel Island population is composed of 2 subpopulations from a sympatric breeding colony but separate wintering areas, whereas the Banks Island population shares a sympatric wintering area in California, USA, with one of the Wrangel Island subpopulations. The Wrangel Island colony represents the last major snow goose population in Russia and has fluctuated considerably since 1970, whereas the Banks Island population has more than doubled. The reasons for these changes are unclear, but hypotheses include independent population demographics (survival and recruitment) and immigration and emigration among breeding or wintering populations. These demographic and movement patterns have important ecological and management implications for understanding goose population structure, harvest of admixed populations, and gene flow among populations with separate breeding or wintering areas. From 1993 to 1996, we neckbanded molting birds at their breeding colonies and resighted birds on the wintering grounds. We used multistate mark-recapture models to evaluate apparent survival rates, resighting rates, winter fidelity, and potential exchange among these populations. We also compared the utility of face stain in Wrangel Island breeding geese as a predictor of their wintering area. Our results showed similar apparent survival rates between subpopulations of Wrangel Island snow geese and lower apparent survival, but higher emigration, for the Banks Island birds. Males had lower apparent survival than females, most likely due to differences in neckband loss. Transition between wintering areas was low (<3%), with equal movement between northern and southern wintering areas for Wrangel Island birds and little evidence of exchange between the Banks and northern Wrangel Island

  3. Jasna: A new winter rapeseed cultivar

    Directory of Open Access Journals (Sweden)

    Marjanović-Jeromela Ana

    2009-01-01

    Full Text Available The program of winter rapeseed breeding at Institute of Field and Vegetable Crops covers the development of winter and spring rapeseed cultivars and hybrids. Winter rapeseed cultivars are selected for high and stabile grain and oil yield, good oil quality, low erucic acid and glucosinolate content (type 00 and tolerance to stresses caused by abiotic and biotic factors. This paper reviews agronomic characteristics and grain and oil quality of a new cultivar of winter rapeseed Jasna. In the trials of the Serbian Commission for new cultivars registration, cultivar Jasna had higher grain yield then standard, in the three locations and two years. In average the yield was 4566 kg/ha. Oil content is at the level of the standard. The erucic acid content and glucosinolate content are lower then that in the standard and that are positive characteristics. .

  4. VT Mean Winter Precipitation - 1971-2000

    Data.gov (United States)

    Vermont Center for Geographic Information — (Link to Metadata) ClimatePrecip_PRECIPW7100 includes mean winter precipitation data (October through March) for Vermont (1971-2000). It's a raster dataset derived...

  5. Esteemed Alumnus, Former POW Honors Winter Graduates

    OpenAIRE

    Stewart, Kenneth A.

    2015-01-01

    The Naval Postgraduate School (NPS) honored some 334 graduates from 17 countries earning 335 advanced degrees during its Winter Quarter Commencement Ceremony in King Auditorium, March 27. NPS President retired Vice Adm. Ronald A. Route presided over the ceremony.

  6. SERSO: Summer sun against winter ice; SERSO: Mit Sommer-Sonne gegen Winter-Glatteis

    Energy Technology Data Exchange (ETDEWEB)

    Eugster, W.J. [Polydynamics Engineering, Zuerich (Switzerland); Hess, K. [Polydynamics Engineering, Bremgarten-Bern (Switzerland); Hopkirk, R.J. [Polydynamics Engineering, Maennedorf (Switzerland)

    1997-12-01

    Road surfaces absorb energy from the incoming solar radiation in the summer months. The SERSO project was conceived to collect this energy, store it and reuse it during the following winter period to eliminate ice formation on those same road surfaces. The acronym SERSO (Sonnenenergierueckgewinnung aus Strassenoberflaechen) means `solar energy recuperation from road surfaces`. This pilot unit having been conceived, researched an applied to a bridge on the Swiss national expressway A8 near Daerligen on the south side of the lake of Thun was officially opened on 22nd August 1994. Heat exchanger tubes carrying a water/glycol heat transfer fluid were built into the roadbed on the bridge, covering a total area of some 1`300 m{sup 2}. In summer these collect heat from the exposed carriageways, which is then transported in a closed hydraulic circuit to the neighbouring cylindrical underground rock heat storage volume. Within a diameter of 31.5 m and a depth of 65 m heat is exchanged between the heat transfer fluid and the rock via an array of 91 borehole heat exchangers. The operation of the pilot plant has been accompanied by detailed measurement campaign, whereby a total of 132 sensors are interrogated by remote datalogger. The data consist of temperature measurements at several depths and positions both in the roadbed and in the rock storage volume, of energy fluxes in the hydraulic system and of relevant meteorological data. The experiences gianed during the first two years of operation have shown that sufficient heat can indeed be collected in summer to maintain the bridge free of ice during the following winter. Moreover the energy balances derived from the measurements in the low temperature rock heat store have confirmed the predicted storage efficiency. (orig./AKF) [Deutsch] cVerkehrsflaechen heizen sich im Sommer durch Sonneneinstrahlung stark auf. Diese Sommerwaerme zu sammeln, zwischenzuspeichern und im Winter zur Verhinderung von Glatteisbildung wieder zu

  7. Drought and Winter Drying (Pest Alert)

    Science.gov (United States)

    USDA Forest Service

    Drought and winter drying have periodically caused major damage to trees. Drought reduces the amount of water available in the soil. In the case of winter drying, the water may be in the soil, but freezing of the soil makes the water unavailable to the tree. In both cases, more water is lost through transpiration than is available to the plant. Symptoms of drought and...

  8. Winter swimming improves general well-being

    OpenAIRE

    Huttunen, Pirkko; Kokko, Leena; Ylijukuri, Virpi

    2004-01-01

    Objectives. This study deals with the effects of regular winter swimming on the mood of the swimmers. Methods. Profile of Mood State (POMS) and OIRE questionnaires were completed before (October) and after (January) the fourmonth winter swimming period. Results. In the beginning, there were no significant differences in the mood states and subjective feelings between the swimmers and the controls. The swimmers had more diseases (about 50%) diagnosed by a physician. Tension, fatigue, memory an...

  9. Norovirus GII.17 as Major Epidemic Strain in Italy, Winter 2015–16

    Science.gov (United States)

    De Grazia, Simona; Bonura, Floriana; Cappa, Vincenzo; Muli, Sara Li; Pepe, Arcangelo; Medici, Maria Cristina; Tummolo, Fabio; Calderaro, Adriana; Di Bernardo, Francesca; Dones, Piera; Morea, Anna; Loconsole, Daniela; Catella, Cristiana; Terio, Valentina; Bànyai, Krisztiàn; Chironna, Maria; Martella, Vito

    2017-01-01

    In winter 2015–16, norovirus GII.17 Kawasaki 2014 emerged as a cause of sporadic gastroenteritis in children in Italy. Median patient age was higher for those with GII.17 than GII.4 infection (55 vs. 24 months), suggesting limited cross-protection for older children. PMID:28628440

  10. New winter hardy winter bread wheat cultivar (Triticum aestivum L. Voloshkova

    Directory of Open Access Journals (Sweden)

    Л. М. Голик

    2007-12-01

    Full Text Available Creation of Initial raw for breeding of winter wheat by change of the development type under low temperatures influence was described. Seeds of spring wheat were vernalized in aluminum weighting bottle. By using low temperatures at sawing of M2-6 at the begin ind of optimal terms of sawing of winter wheat, new winter-hardy variety of Voloshkova was bred.

  11. River catchment rainfall series analysis using additive Holt-Winters method

    Science.gov (United States)

    Puah, Yan Jun; Huang, Yuk Feng; Chua, Kuan Chin; Lee, Teang Shui

    2016-03-01

    Climate change is receiving more attention from researchers as the frequency of occurrence of severe natural disasters is getting higher. Tropical countries like Malaysia have no distinct four seasons; rainfall has become the popular parameter to assess climate change. Conventional ways that determine rainfall trends can only provide a general result in single direction for the whole study period. In this study, rainfall series were modelled using additive Holt-Winters method to examine the rainfall pattern in Langat River Basin, Malaysia. Nine homogeneous series of more than 25 years data and less than 10% missing data were selected. Goodness of fit of the forecasted models was measured. It was found that seasonal rainfall model forecasts are generally better than the monthly rainfall model forecasts. Three stations in the western region exhibited increasing trend. Rainfall in southern region showed fluctuation. Increasing trends were discovered at stations in the south-eastern region except the seasonal analysis at station 45253. Decreasing trend was found at station 2818110 in the east, while increasing trend was shown at station 44320 that represents the north-eastern region. The accuracies of both rainfall model forecasts were tested using the recorded data of years 2010-2012. Most of the forecasts are acceptable.

  12. EXCLUSIVELY FOR SIX MONTHS

    African Journals Online (AJOL)

    Method: Infant feeding practices was studied prospectively among 461 mothers who delivered in JU TH and who initially intended to breastfeed exclusively for 6 months. K. Y Result: Four hundred and twenty two (91.5%) of the recruited mothers continued EBFing practice for 6 months, while 25 (5.4%) dropped out from the ...

  13. Birth Month Affects Longevity

    Science.gov (United States)

    Abel, Ernest L.; Kruger, Michael L.

    2010-01-01

    The authors examined the association between birth month and longevity for major league baseball players. Players born in the month of November had the greatest longevities whereas those born in June had the shortest life spans. These differences remained after controlling for covariates such as birth year, career length, age at debut, height, and…

  14. Progress report, 36 months

    DEFF Research Database (Denmark)

    Juhl, Thomas Winther; Nielsen, Jakob Skov

    The work performed during the past 12 months (months 13 – 24) of the project has included the conclusion of Task 1 – Fundamental Studies and Task 2 – Multimirror Cutting Head Design. Work on Task 3 – Compact Cutting Head Design, and Task 4 – Interface Design has been carried out and the tests of ...

  15. Progress report, 24 months

    DEFF Research Database (Denmark)

    Juhl, Thomas Winther; Nielsen, Jakob Skov

    The work performed during the past 12 months (months 13 – 24) of the project has included the conclusion of Task 1 – Fundamental Studies and Task 2 – Multimirror Cutting Head Design. Work on Task 3 – Compact Cutting Head Design, and Task 4 – Interface Design has been carried out and the tests of ...

  16. No evidence that migratory geese disperse avian influenza viruses from breeding to wintering ground.

    Directory of Open Access Journals (Sweden)

    Shenglai Yin

    Full Text Available Low pathogenic avian influenza virus can mutate to a highly pathogenic strain that causes severe clinical signs in birds and humans. Migratory waterfowl, especially ducks, are considered the main hosts of low pathogenic avian influenza virus, but the role of geese in dispersing the virus over long-distances is still unclear. We collected throat and cloaca samples from three goose species, Bean goose (Anser fabalis, Barnacle goose (Branta leucopsis and Greater white-fronted goose (Anser albifrons, from their breeding grounds, spring stopover sites, and wintering grounds. We tested if the geese were infected with low pathogenic avian influenza virus outside of their wintering grounds, and analysed the spatial and temporal patterns of infection prevalence on their wintering grounds. Our results show that geese were not infected before their arrival on wintering grounds. Barnacle geese and Greater white-fronted geese had low prevalence of infection just after their arrival on wintering grounds in the Netherlands, but the prevalence increased in successive months, and peaked after December. This suggests that migratory geese are exposed to the virus after their arrival on wintering grounds, indicating that migratory geese might not disperse low pathogenic avian influenza virus during autumn migration.

  17. Gene therapy rescues cone structure and function in the 3-month-old rd12 mouse: a model for midcourse RPE65 leber congenital amaurosis.

    Science.gov (United States)

    Li, Xia; Li, Wensheng; Dai, Xufeng; Kong, Fansheng; Zheng, Qinxiang; Zhou, Xiangtian; Lü, Fan; Chang, Bo; Rohrer, Bärbel; Hauswirth, William W; Qu, Jia; Pang, Ji-jing

    2011-01-01

    RPE65 function is necessary in the retinal pigment epithelium (RPE) to generate chromophore for all opsins. Its absence results in vision loss and rapid cone degeneration. Recent Leber congenital amaurosis type 2 (LCA with RPE65 mutations) phase I clinical trials demonstrated restoration of vision on RPE65 gene transfer into RPE cells overlying cones. In the rd12 mouse, a naturally occurring model of RPE65-LCA early cone degeneration was observed; however, some peripheral M-cones remained. A prior study showed that AAV-mediated RPE65 expression can prevent early cone degeneration. The present study was conducted to test whether the remaining cones in older rd12 mice can be rescued. Subretinal treatment with the scAAV5-smCBA-hRPE65 vector was initiated at postnatal day (P)14 and P90. After 2 months, electroretinograms were recorded, and cone morphology was analyzed by using cone-specific peanut agglutinin and cone opsin-specific antibodies. Cone degeneration started centrally and spread ventrally, with cells losing cone-opsin staining before that for the PNA-lectin-positive cone sheath. Gene therapy starting at P14 resulted in almost wild-type M- and S-cone function and morphology. Delaying gene-replacement rescued the remaining M-cones, and most important, more M-cone opsin-positive cells were identified than were present at the onset of gene therapy, suggesting that opsin expression could be reinitiated in cells with cone sheaths. The results support and extend those of the previous study that gene therapy can stop early cone degeneration, and, more important, they provide proof that delayed treatment can restore the function and morphology of the remaining cones. These results have important implications for the ongoing LCA2 clinical trials.

  18. Winter survival of Eurasian woodcock Scolopax rusticola in central Italy

    Science.gov (United States)

    Aradis, A.; Miller, M.W.; Landucci, G.; Ruda, P.; Taddei, S.; Spina, F.

    2008-01-01

    The Eurasian woodcock Scolopax rusticola is a popular game bird in much of Europe. However, little is known about its population dynamics. We estimated winter survival of woodcock in a protected area with no hunting in central Italy. We radio-tagged 68 woodcocks with battery-powered radio-transmitters during 2001-2005. Woodcocks were captured in fields at night from November through February and fitted with radios. Birds were classified on capture as juveniles or adults using plumage characteristics. Woodcocks were relocated daily through March of each year or until they died, disappeared from the study area, or until their radio failed. We constructed a set of eight competing models of daily survival for the period 1 December - 28 February. Estimates of survival were obtained using the program SURVIV and Akaike's Information Criteria. The best model suggested daily survival was a constant 0.9985 (95% CI = 0.9972-0.9998), corresponding to a survival rate of 0.88 (SE = 0.05) for the 90-day winter study period. Our estimate of juvenile survival is higher than previously reported, and may reflect the protected status of the study area. Our estimates of winter survival may be helpful in managing harvested woodcock populations as well as in conserving populations in an increasingly urbanised environment. ?? Wildlife Biology (2008).

  19. Surface wind energy trends near Taiwan in winter since 1871

    Directory of Open Access Journals (Sweden)

    Lei Zhang

    2017-01-01

    Full Text Available The tropical surface wind speed in boreal winter reaches a maximum near Taiwan. This stable wind resource may be used for future clean energy development. How this surface wind energy source has changed in past 141 years is investigated using the 20th century reanalysis dataset and CMIP5 models. Our observational analysis shows that the surface wind speed experienced a weakening trend in the past 141 years (1871 - 2010. The average decreasing rate is around -1.4 m s-1 per century. The decrease is primarily attributed to the relative sea surface temperature (SST cooling in the subtropical North Pacific, which forces a large-scale low-level anti-cyclonic circulation anomaly in situ and is thus responsible for the southerly trend near Taiwan. The relative SST trend pattern is attributed mainly to the greenhouse gas effect associated with anthropogenic activities. The southerly trend near Taiwan is more pronounced in the boreal winter than in summer. Such seasonal difference is attributed to the reversed seasonal mean wind, which promotes more efficient positive feedback in the boreal winter. The CMIP5 historical run analysis reveals that climate models capture less SST warming and large-scale anti-cyclonic circulation in the subtropical North Pacific, but the simulated weakening trend of the surface wind speed near Taiwan is too small.

  20. Winter distribution of Calanus finmarchicus in the Northeast Atlantic

    DEFF Research Database (Denmark)

    Heath, M.R.; Fraser, J.G.; Gislason, A.

    2000-01-01

    Data from plankton sampling and Optical Plankton Counter deployments during six cruises between December of 1994 and 1999 have been used to derive a composite three-dimensional distribution of the abundance of Calanus finmarchicus during winter (December-January) in the Norwegian Sea and Northeast...... Atlantic. There are two centres of abundance, one in the eastern Norwegian Sea and Faroe-Shetland Channel, associated with the interface between Norwegian Sea Deep Water and Intermediate Water layers, and another in the Irminger Sea southwest of Iceland in association with Labrador Sea Water. In the open...... Northeast Atlantic, the concentration of wintering animals is around 30% of that in the Norwegian Sea and the vertical distribution is more diffuse and on average deeper. Modelling studies have shown that the overwinter distribution and transport are key factors determining the spatial persistence of C...

  1. Tillage Management and Seasonal Effects on Denitrifier Community Abundance, Gene Expression and Structure over Winter.

    Science.gov (United States)

    Tatti, Enrico; Goyer, Claudia; Burton, David L; Wertz, Sophie; Zebarth, Bernie J; Chantigny, Martin; Filion, Martin

    2015-10-01

    Tillage effects on denitrifier communities and nitrous oxide (N2O) emissions were mainly studied during the growing season. There is limited information for the non-growing season, especially in northern countries where winter has prolonged periods with sub-zero temperatures. The abundance and structure of the denitrifier community, denitrification gene expression and N2O emissions in fields under long-term tillage regimes [no-tillage (NT) vs conventional tillage (CT)] were assessed during two consecutive winters. NT exerted a positive effect on nirK and nosZ denitrifier abundance in both winters compared to CT. Moreover, the two contrasting managements had an opposite influence on nirK and nirS RNA/DNA ratios. Tillage management resulted in different denitrifier community structures during both winters. Seasonal changes were observed in the abundance and the structure of denitrifiers. Interestingly, the RNA/DNA ratios were greater in the coldest months for nirK, nirS and nosZ. N2O emissions were not influenced by management but changed over time with two orders of magnitude increase in the coldest month of both winters. In winter of 2009-2010, emissions were mainly as N2O, whereas in 2010-2011, when soil temperatures were milder due to persistent snow cover, most emissions were as dinitrogen. Results indicated that tillage management during the growing season induced differences in denitrifier community structure that persisted during winter. However, management did not affect the active cold-adapted community structure.

  2. Predictable climate dynamics of abnormal East Asian winter monsoon: once-in-a-century snowstorms in 2007/2008 winter

    Science.gov (United States)

    Wu, Zhiwei; Li, Jianping; Jiang, Zhihong; He, Jinhai

    2011-10-01

    In 2008 (January-February), East Asia (EA) experiences the most severe and long-persisting snowstorm in the past 100 years. Results in this study show that 2007/2008 winter is dominant by the third principal mode of the East Asian winter monsoon (EAWM) which explains 8.7% of the total surface air temperature variance over EA. Significantly distinguished from the first two leading modes, the third mode positive phase features an increased surface pressure over the northwestern EA, an enhanced central Siberian high (CSH), a strengthened and northwestward extended western Pacific subtropical high (WPSH) and anomalously strong moisture transport from western Pacific, Arabian Sea and Bay of Bengal to EA. It also exhibits an intimate linkage with the sea surface temperature anomalies (SSTAs) in the Arctic Ocean areas adjacent to northern Eurasian continent, central North Pacific and northeastern Pacific. Such SSTAs emerge in prior autumn and persist through ensuing winter, signifying precursory conditions for the anomalous third EAWM mode. Numerical experiments with a simple general circulation model demonstrate that the Arctic SSTAs excite geo-potential height anomalies over northern Eurasian continent and impacts on the CSH, while the extra-tropical Pacific SSTAs deform the WPSH. Co-effects of them play crucial roles on origins of the third EAWM mode. Based on these results, an empirical model is established to predict the third mode of the EAWM. Hindcast is performed for the 1957-2008 period, which shows a quite realistic prediction skill in general and good prediction ability in the extreme phase of the third mode of the EAWM such as 2007/2008 winter. Since all these predictors can be readily monitored in real time, this empirical model provides a real time forecast tool and may facilitate the seasonal prediction of high-impact weather associated with the abnormal EAWM.

  3. Predictable climate dynamics of abnormal East Asian winter monsoon: once-in-a-century snowstorms in 2007/2008 winter

    Energy Technology Data Exchange (ETDEWEB)

    Wu, Zhiwei [Chinese Academy of Sciences, LASG, Institute of Atmospheric Physics, Beijing (China); Environment Canada, Meteorological Research Division, Dorval, QC (Canada); Li, Jianping [Chinese Academy of Sciences, LASG, Institute of Atmospheric Physics, Beijing (China); Jiang, Zhihong; He, Jinhai [Nanjing University of Information Science and Technology, Key Laboratory of Meteorological Disaster of Ministry of Education, Nanjing (China)

    2011-10-15

    In 2008 (January-February), East Asia (EA) experiences the most severe and long-persisting snowstorm in the past 100 years. Results in this study show that 2007/2008 winter is dominant by the third principal mode of the East Asian winter monsoon (EAWM) which explains 8.7% of the total surface air temperature variance over EA. Significantly distinguished from the first two leading modes, the third mode positive phase features an increased surface pressure over the northwestern EA, an enhanced central Siberian high (CSH), a strengthened and northwestward extended western Pacific subtropical high (WPSH) and anomalously strong moisture transport from western Pacific, Arabian Sea and Bay of Bengal to EA. It also exhibits an intimate linkage with the sea surface temperature anomalies (SSTAs) in the Arctic Ocean areas adjacent to northern Eurasian continent, central North Pacific and northeastern Pacific. Such SSTAs emerge in prior autumn and persist through ensuing winter, signifying precursory conditions for the anomalous third EAWM mode. Numerical experiments with a simple general circulation model demonstrate that the Arctic SSTAs excite geo-potential height anomalies over northern Eurasian continent and impacts on the CSH, while the extra-tropical Pacific SSTAs deform the WPSH. Co-effects of them play crucial roles on origins of the third EAWM mode. Based on these results, an empirical model is established to predict the third mode of the EAWM. Hindcast is performed for the 1957-2008 period, which shows a quite realistic prediction skill in general and good prediction ability in the extreme phase of the third mode of the EAWM such as 2007/2008 winter. Since all these predictors can be readily monitored in real time, this empirical model provides a real time forecast tool and may facilitate the seasonal prediction of high-impact weather associated with the abnormal EAWM. (orig.)

  4. GLDAS Noah Land Surface Model L4 monthly 0.25 x 0.25 degree V2.1 (GLDAS_NOAH025_M) at GES DISC

    Data.gov (United States)

    National Aeronautics and Space Administration — This data product is a replacement for GLDAS-1 0.25 degree monthly data product. Global Land Data Assimilation System Version 2 (hereafter, GLDAS-2) has two...

  5. Carryover effects associated with winter location affect fitness, social status, and population dynamics in a long-distance migrant

    Science.gov (United States)

    Sedinger, James S.; Schamber, Jason L.; Ward, David H.; Nicolai, Christopher A.; Conant, Bruce

    2011-01-01

    We used observations of individually marked female black brant geese (Branta bernicla nigricans; brant) at three wintering lagoons on the Pacific coast of Baja California—Laguna San Ignacio (LSI), Laguna Ojo de Liebre (LOL), and Bahía San Quintín (BSQ)—and the Tutakoke River breeding colony in Alaska to assess hypotheses about carryover effects on breeding and distribution of individuals among wintering areas. We estimated transition probabilities from wintering locations to breeding and nonbreeding by using multistratum robust-design capture-mark-recapture models. We also examined the effect of breeding on migration to wintering areas to assess the hypothesis that individuals in family groups occupied higher-quality wintering locations. We used 4,538 unique female brant in our analysis of the relationship between winter location and breeding probability. All competitive models of breeding probability contained additive effects of wintering location and the 1997–1998 El Niño–Southern Oscillation (ENSO) event on probability of breeding. Probability of breeding in non-ENSO years was 0.98 ± 0.02, 0.68 ± 0.04, and 0.91 ± 0.11 for females wintering at BSQ, LOL, and LSI, respectively. After the 1997–1998 ENSO event, breeding probability was between 2% (BSQ) and 38% (LOL) lower than in other years. Individuals that bred had the highest probability of migrating the next fall to the wintering area producing the highest probability of breeding.

  6. First Direct Evidence for Natal Wintering Ground Fidelity and Estimate of Juvenile Survival in the New Zealand Southern Right Whale Eubalaena australis.

    Science.gov (United States)

    Carroll, E L; Fewster, R M; Childerhouse, S J; Patenaude, N J; Boren, L; Baker, C S

    2016-01-01

    Juvenile survival and recruitment can be more sensitive to environmental, ecological and anthropogenic factors than adult survival, influencing population-level processes like recruitment and growth rate in long-lived, iteroparous species such as southern right whales. Conventionally, Southern right whales are individually identified using callosity patterns, which do not stabilise until 6-12 months, by which time the whale has left its natal wintering grounds. Here we use DNA profiling of skin biopsy samples to identify individual Southern right whales from year of birth and document their return to the species' primary wintering ground in New Zealand waters, the Subantarctic Auckland Islands. We find evidence of natal fidelity to the New Zealand wintering ground by the recapture of 15 of 57 whales, first sampled in year of birth and available for subsequent recapture, during winter surveys to the Auckland Islands in 1995-1998 and 2006-2009. Four individuals were recaptured at the ages of 9 to 11, including two females first sampled as calves in 1998 and subsequently resampled as cows with calves in 2007. Using these capture-recapture records of known-age individuals, we estimate changes in survival with age using Cormack-Jolly-Seber models. Survival is modelled using discrete age classes and as a continuous function of age. Using a bootstrap method to account for uncertainty in model selection and fitting, we provide the first direct estimate of juvenile survival for this population. Our analyses indicate a high annual apparent survival for juveniles at between 0.87 (standard error (SE) 0.17, to age 1) and 0.95 (SE 0.05: ages 2-8). Individual identification by DNA profiling is an effective method for long-term demographic and genetic monitoring, particularly in animals that change identifiable features as they develop or experience tag loss over time.

  7. Examining winter visitor use in Yellowstone National Park

    Science.gov (United States)

    Mae A. Davenport; Wayne A. Freimund; William T. Borrie; Robert E. Manning; William A. Valliere; Benjamin Wang

    2000-01-01

    This research was designed to assist the managers of Yellowstone National Park (YNP) in their decision making about winter visitation. The focus of this report is on winter use patterns and winter visitor preferences. It is the author’s hope that this information will benefit both the quality of winter experiences and the stewardship of the park resources. This report...

  8. Oceanographic Monthly Summary

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Oceanographic Monthly Summary contains sea surface temperature (SST) analyses on both regional and ocean basin scales for the Atlantic, Pacific, and Indian Oceans....

  9. Children's Health Month 2017

    Science.gov (United States)

    October is Children's Health month, with information and links that you can use -- in October and throughout the year. We will work with parents, teachers, and health providers to promote healthy environments where children live, learn and play.

  10. TARP Monthly Housing Scorecard

    Data.gov (United States)

    Department of the Treasury — Treasury and the U.S. Department of Housing and Urban Development (HUD) jointly produce a Monthly Housing Scorecard on the health of the nation’s housing market. The...

  11. Soil erosion in an avalanche release site (Valle d'Aosta: Italy): towards a winter factor for RUSLE in the Alps

    Science.gov (United States)

    Stanchi, S.; Freppaz, M.; Ceaglio, E.; Maggioni, M.; Meusburger, K.; Alewell, C.; Zanini, E.

    2014-07-01

    Soil erosion in Alpine areas is mainly related to extreme topographic and weather conditions. Although different methods of assessing soil erosion exist, the knowledge of erosive forces of the snow cover needs more investigation in order to allow soil erosion modeling in areas where the snow lays on the ground for several months. This study aims to assess whether the RUSLE (Revised Universal Soil Loss Equation) empirical prediction model, which gives an estimation of water erosion in t ha yr-1 obtained from a combination of five factors (rainfall erosivity, soil erodibility, topography, soil cover, protection practices) can be applied to mountain areas by introducing a winter factor (W), which should account for the soil erosion occurring in winter time by the snow cover. The W factor is calculated from the ratio of Ceasium-137 (137Cs) to RUSLE erosion rates. Ceasium-137 is another possible way of assessing soil erosion rates in the field. In contrast to RUSLE, it not only provides water-induced erosion but integrates all erosion agents involved. Thus, we hypothesize that in mountain areas the difference between the two approaches is related to the soil erosion by snow. In this study we compared 137Cs-based measurement of soil redistribution and soil loss estimated with RUSLE in a mountain slope affected by avalanches, in order to assess the relative importance of winter erosion processes such as snow gliding and full-depth avalanches. Three subareas were considered: DS, avalanche defense structures, RA, release area, and TA, track area, characterized by different prevalent winter processes. The RUSLE estimates and the 137Cs redistribution gave significantly different results. The resulting ranges of W evidenced relevant differences in the role of winter erosion in the considered subareas, and the application of an avalanche simulation model corroborated these findings. Thus, the higher rates obtained with the 137Cs method confirmed the relevant role of winter soil

  12. Genomic Prediction of Manganese Efficiency in Winter Barley

    Directory of Open Access Journals (Sweden)

    Florian Leplat

    2016-07-01

    Full Text Available Manganese efficiency is a quantitative abiotic stress trait controlled by several genes each with a small effect. Manganese deficiency leads to yield reduction in winter barley ( L.. Breeding new cultivars for this trait remains difficult because of the lack of visual symptoms and the polygenic features of the trait. Hence, Mn efficiency is a potential suitable trait for a genomic selection (GS approach. A collection of 248 winter barley varieties was screened for Mn efficiency using Chlorophyll (Chl fluorescence in six environments prone to induce Mn deficiency. Two models for genomic prediction were implemented to predict future performance and breeding value of untested varieties. Predictions were obtained using multivariate mixed models: best linear unbiased predictor (BLUP and genomic best linear unbiased predictor (G-BLUP. In the first model, predictions were based on the phenotypic evaluation, whereas both phenotypic and genomic marker data were included in the second model. Accuracy of predicting future phenotype, , and accuracy of predicting true breeding values, , were calculated and compared for both models using six cross-validation (CV schemes; these were designed to mimic plant breeding programs. Overall, the CVs showed that prediction accuracies increased when using the G-BLUP model compared with the prediction accuracies using the BLUP model. Furthermore, the accuracies [] of predicting breeding values were more accurate than accuracy of predicting future phenotypes []. The study confirms that genomic data may enhance the prediction accuracy. Moreover it indicates that GS is a suitable breeding approach for quantitative abiotic stress traits.

  13. Seasonal overturning circulation in the Red Sea: 2. Winter circulation

    KAUST Repository

    Yao, Fengchao

    2014-04-01

    The shallow winter overturning circulation in the Red Sea is studied using a 50 year high-resolution MITgcm (MIT general circulation model) simulation with realistic atmospheric forcing. The overturning circulation for a typical year, represented by 1980, and the climatological mean are analyzed using model output to delineate the three-dimensional structure and to investigate the underlying dynamical mechanisms. The horizontal model circulation in the winter of 1980 is dominated by energetic eddies. The climatological model mean results suggest that the surface inflow intensifies in a western boundary current in the southern Red Sea that switches to an eastern boundary current north of 24N. The overturning is accomplished through a cyclonic recirculation and a cross-basin overturning circulation in the northern Red Sea, with major sinking occurring along a narrow band of width about 20 km along the eastern boundary and weaker upwelling along the western boundary. The northward pressure gradient force, strong vertical mixing, and horizontal mixing near the boundary are the essential dynamical components in the model\\'s winter overturning circulation. The simulated water exchange is not hydraulically controlled in the Strait of Bab el Mandeb; instead, the exchange is limited by bottom and lateral boundary friction and, to a lesser extent, by interfacial friction due to the vertical viscosity at the interface between the inflow and the outflow. Key Points Sinking occurs in a narrow boundary layer along the eastern boundary Surface western boundary current switches into an eastern boundary current Water exchange in the Strait of Bab el Mandeb is not hydraulically controlled © 2014. American Geophysical Union. All Rights Reserved.

  14. Root development of fodder radish and winter wheat before winter in relation to uptake of nitrogen

    DEFF Research Database (Denmark)

    Wahlström, Ellen Margrethe; Hansen, Elly Møller; Mandel, A.

    2015-01-01

    occurred. Quantitative data is missing on N leaching of a catch crop compared to a winter cereal in a conventional cereal-based cropping system. The aim of the study was to investigate whether fodder radish (Raphanus sativus L.) (FR) would be more efficient than winter wheat (Triticum aestivum L.) (WW...

  15. Attributions of meteorological and emission factors to the 2015 winter severe haze pollution episodes in China's Jing-Jin-Ji area

    Science.gov (United States)

    Liu, Tingting; Gong, Sunling; He, Jianjun; Yu, Meng; Wang, Qifeng; Li, Huairui; Liu, Wei; Zhang, Jie; Li, Lei; Wang, Xuguan; Li, Shuli; Lu, Yanli; Du, Haitao; Wang, Yaqiang; Zhou, Chunhong; Liu, Hongli; Zhao, Qichao

    2017-02-01

    In the 2015 winter month of December, northern China witnessed the most severe air pollution phenomena since the 2013 winter haze events occurred. This triggered the first-ever red alert in the air pollution control history of Beijing, with an instantaneous fine particulate matter (PM2. 5) concentration over 1 mg m-3. Air quality observations reveal large temporal-spatial variations in PM2. 5 concentrations over the Beijing-Tianjin-Hebei (Jing-Jin-Ji) area between 2014 and 2015. Compared to 2014, the PM2. 5 concentrations over the area decreased significantly in all months except November and December of 2015, with an increase of 36 % in December. Analysis shows that the PM2. 5 concentrations are significantly correlated with the local meteorological parameters in the Jing-Jin-Ji area such as the stable conditions, relative humidity (RH), and wind field. A comparison of two month simulations (December 2014 and 2015) with the same emission data was performed to explore and quantify the meteorological impacts on the PM2. 5 over the Jing-Jin-Ji area. Observation and modeling results show that the worsening meteorological conditions are the main reasons behind this unusual increase of air pollutant concentrations and that the emission control measures taken during this period of time have contributed to mitigate the air pollution ( ˜ 9 %) in the region. This work provides a scientific insight into the emission control measures vs. the meteorology impacts for the period.

  16. Twentieth Century Winter Changes in Southern Hemisphere Synoptic Weather Modes

    Directory of Open Access Journals (Sweden)

    Jorgen S. Frederiksen

    2011-01-01

    Full Text Available During the last sixty years, there have been large changes in the southern hemisphere winter circulation and reductions in rainfall particularly in the southern Australian region. Here we examine the corresponding changes in dynamical modes of variability ranging from storm tracks, onset-of-blocking modes, northwest cloud-band disturbances, Antarctic low-frequency modes, intraseasonal oscillations, and African easterly waves. Our study is performed using a global two-level primitive equation instability-model with reanalyzed observed July three-dimensional basic states for the periods 1949–1968, 1975–1994, and 1997–2006. We relate the reduction in the winter rainfall in the southwest of Western Australia since the mid-1970s and in south-eastern Australia since the mid-1990s to changes in growth rate and structures of leading storm track and blocking modes. We find that cyclogenesis and onset-of-blocking modes growing on the subtropical jet have significantly reduced growth rates in the latter periods. On the other hand there is a significant increase in the growth rate of northwest cloud-band modes and intraseasonal oscillation disturbances that cross Australia and are shown to be related to recent positive trends in winter rainfall over northwest Western Australia and central Australia, in general. The implications of our findings are discussed.

  17. Decadal predictability of winter windstorm frequency in Eastern Europe

    Science.gov (United States)

    Höschel, Ines; Grieger, Jens; Ulbrich, Uwe

    2017-04-01

    Winter windstorms are one of the most impact relevant extreme-weather events in Europe. This study is focussed on windstorm frequency in Eastern Europe at multi-year time scale. Individual storms are identified by using 6-hourly 10m-wind-fields. The impact-oriented tracking algorithm is based on the exceedance of the local 98 percentile of wind speed and a minimum duration of 18 hours. Here, storm frequency is the number of 1000km-footprints of identified windstorms touching the location during extended boreal winter from October to March. The temporal development of annual storm frequencies in Eastern Europe shows variations on a six to fifteen years period. Higher than normal windstorm frequency occurred end of the 1950s and in beginning of the seventies, while lower than normal frequency were around 1960 and in the forties, for example. The correlation between bandpass filtered storm frequency and North Atlantic sea surface temperature shows a significant pattern with a positive correlation in the subtropical East Atlantic and significant negative correlations in the Gulfstream region. The relationship between these multi-year variations and predictability on decadal time scales is discussed. The resulting skill of winter wind storms in the German decadal prediction system MiKlip, based on the numerical earth system model MPI-ESM, will be presented.

  18. Foraging flight distances of wintering ducks and geese: a review

    Directory of Open Access Journals (Sweden)

    William P. Johnson

    2014-12-01

    Full Text Available The distance covered by foraging animals, especially those that radiate from a central area when foraging, may affect ecosystem, community, and population dynamics, and has conservation and landscape planning implications for multiple taxa, including migratory waterfowl. Migrating and wintering waterfowl make regular foraging flights between roosting and feeding areas that can greatly impact energetic resources within the foraging zone near roost sites. We reviewed published studies and gray literature for one-way foraging flight distances (FFDs of migrating and wintering dabbling ducks and geese. Thirty reviewed studies reported FFDs and several reported values for multiple species or locations. We obtained FFD values for migration (n = 7 and winter (n = 70. We evaluated the effects of body mass, guild, i.e., dabbling duck or goose, and location, i.e., Nearctic or Palearctic, on FFDs. We used the second-order Akaike's Information Criterion for model selection. We found support for effects of location and guild on FFDs. FFDs of waterfowl wintering in the Nearctic (7.4 ± 6.7 km, mean ± SD; n = 39 values were longer than in the Palearctic (4.2 ± 3.2 km; n = 31 values. The FFDs of geese (7.8 ± 7.2 km, mean ± SD; n = 24 values were longer than FFDs of dabbling ducks (5.1 ± 4.4 km, mean ± SD; n = 46 values. We found mixed evidence that distance flown from the roost changed, i.e., increased or decreased, seasonally. Our results can be used to refine estimates of energetic carrying capacity around roosts and in biological and landscape planning efforts.

  19. The engineering approach to winter sports

    CERN Document Server

    Cheli, Federico; Maldifassi, Stefano; Melzi, Stefano; Sabbioni, Edoardo

    2016-01-01

    The Engineering Approach to Winter Sports presents the state-of-the-art research in the field of winter sports in a harmonized and comprehensive way for a diverse audience of engineers, equipment and facilities designers, and materials scientists. The book examines the physics and chemistry of snow and ice with particular focus on the interaction (friction) between sports equipment and snow/ice, how it is influenced by environmental factors, such as temperature and pressure, as well as by contaminants and how it can be modified through the use of ski waxes or the microtextures of blades or ski soles. The authors also cover, in turn, the different disciplines in winter sports:  skiing (both alpine and cross country), skating and jumping, bob sledding and skeleton, hockey and curling, with attention given to both equipment design and on the simulation of gesture and  track optimization.

  20. Dispersion of atmospheric air pollution in summer and winter season.

    Science.gov (United States)

    Cichowicz, Robert; Wielgosiński, Grzegorz; Fetter, Wojciech

    2017-11-04

    Seasonal variation of air pollution is associated with variety of seasons and specificity of particular months which form the so-called summer and winter season also known as the "heating" season. The occurrence of higher values of air pollution in different months of a year is associated with the type of climate, and accordingly with different atmospheric conditions in particular months, changing state of weather on a given day, and anthropogenic activity. The appearance of these conditions results in different levels of air pollution characteristic for a given period. The study uses data collected during a seven-year period (2009-2015) in the automatic measuring station of immissions located in Eastern Wielkopolska. The analysis concerns the average and maximum values of air pollution (i.e., particulate matter PM10, sulfur dioxide, nitrogen dioxide, carbon monoxide, and ozone) from the perspective of their occurrence in particular seasons and months or in relation to meteorological actors such as temperature, humidity, and wind speed.