WorldWideScience

Sample records for long-term climatic change

  1. Long-term ecophysiological responses to climate change

    DEFF Research Database (Denmark)

    Boesgaard, Kristine Stove; Ro-Poulsen, Helge

    Plant physiology is affected by climate change. Acclimations of photosynthetic processes are induced by short-term changes in climatic conditions. Further acclimation can be caused by longterm adjustments to climate change due to ecosystem-feedbacks. The aim of this PhD was to investigate plant...... term responses of plant physiology to the climate change factors were investigated. In the CLIMAITE-experiment it has been shown that 2 years of treatment altered physiological responses in Deschampsiaand Calluna. In the work of this PhD similar responses were observed after 6 years of treatment...... physiological responses to climate change in a seasonal and long-term perspective. The effects of elevated CO2, passive night time warming and periodic summer drought as single factor and in combination, on plant physiology were investigated in the long-term multifactorial field experiment CLIMAITE in a Danish...

  2. Long-term bird study records Arctic climate change

    Science.gov (United States)

    Zielinski, Sarah

    Alaska's summer of 2005 was the second warmest on record there, with a record retreat of arctic pack ice. As Alaskan temperatures gradually increase, artic birds, such as the black guillemots of Cooper Island, near Barrow, Alaska, are experiencing drastic habitat changes. Though these small black and white birds—the subjects of a long-term study of climate change—fared better this year than they have in the recent past (due to local cool conditions), they are nonetheless struggling to adapt as their artic island summer home becomes subarctic.George Divokyan ornithologist at the Institute of Arctic Biology, University of Alaska Fairbanks, discovered the Cooper Island colony of guillemots in the early 1970s and has spent every summer since 1975 there studying these birds. He presented his latest research during a 3 November talk in Washington, D.C.

  3. Long-term wave measurements in a climate change perspective.

    Science.gov (United States)

    Pomaro, Angela; Bertotti, Luciana; Cavaleri, Luigi; Lionello, Piero; Portilla-Yandun, Jesus

    2017-04-01

    At present multi-decadal time series of wave data needed for climate studies are generally provided by long term model simulations (hindcasts) covering the area of interest. Examples, among many, at different scales are wave hindcasts adopting the wind fields of the ERA-Interim reanalysis of the European Centre for Medium-Range Weather Forecasts (ECMWF, Reading, U.K.) at the global level and by regional re-analysis as for the Mediterranean Sea (Lionello and Sanna, 2006). Valuable as they are, these estimates are necessarily affected by the approximations involved, the more so because of the problems encountered within modelling processes in small basins using coarse resolution wind fields (Cavaleri and Bertotti, 2004). On the contrary, multi-decadal observed time series are rare. They have the evident advantage of somehow representing the real evolution of the waves, without the shortcomings associated with the limitation of models in reproducing the actual processes and the real variability within the wave fields. Obviously, observed wave time series are not exempt of problems. They represent a very local information, hence their use to describe the wave evolution at large scale is sometimes arguable and, in general, it needs the support of model simulations assessing to which extent the local value is representative of a large scale evolution. Local effects may prevent the identification of trends that are indeed present at large scale. Moreover, a regular maintenance, accurate monitoring and metadata information are crucial issues when considering the reliability of a time series for climate applications. Of course, where available, especially if for several decades, measured data are of great value for a number of reasons and can be valuable clues to delve further into the physics of the processes of interest, especially if considering that waves, as an integrated product of the local climate, if available in an area sensitive to even limited changes of the

  4. Long term impact of climate change on the metropolitan coast

    International Nuclear Information System (INIS)

    2011-01-01

    In its first part, this report describes global physical phenomena: air and sea temperature rise, modification of the tempest regime, precipitations, ocean stratification. Then, it describes some more specific physical effects of climate change: average sea level rise, sea currents (global, regional and local oceanic circulation), and wave modification on the coast. It describes the effects of various media due to sea submersion, erosion and accretion, ocean acidification, salinization increase of underground coastal waters, modification of the composition of biotic communities, biological invasions, and appearance of new toxicities for mankind

  5. Emulation of long-term changes in global climate: Application to the late Pliocene and future

    KAUST Repository

    Lord, Natalie S.

    2017-04-26

    Multi-millennial transient simulations of climate changes have a range of important applications, such as for investigating key geologic events and transitions for which high-resolution palaeoenvironmental proxy data are available, or for projecting the long-term impacts of future climate evolution on the performance of geological repositories for the disposal of radioactive wastes. However, due to the high computational requirements of current fully coupled general circulation models (GCMs), long-term simulations can generally only be performed with less complex models and/or at lower spatial resolution. In this study, we present novel long-term

  6. Emulation of long-term changes in global climate: application to the late Pliocene and future

    KAUST Repository

    Lord, Natalie S.

    2017-11-16

    Multi-millennial transient simulations of climate changes have a range of important applications, such as for investigating key geologic events and transitions for which high-resolution palaeoenvironmental proxy data are available, or for projecting the long-term impacts of future climate evolution on the performance of geological repositories for the disposal of radioactive wastes. However, due to the high computational requirements of current fully coupled general circulation models (GCMs), long-term simulations can generally only be performed with less complex models and/or at lower spatial resolution. In this study, we present novel long-term

  7. Emulation of long-term changes in global climate: application to the late Pliocene and future

    KAUST Repository

    Lord, Natalie S.; Crucifix, Michel; Lunt, Dan J.; Thorne, Mike C.; Bounceur, Nabila; Dowsett, Harry; O& apos; Brien, Charlotte L.; Ridgwell, Andy

    2017-01-01

    Multi-millennial transient simulations of climate changes have a range of important applications, such as for investigating key geologic events and transitions for which high-resolution palaeoenvironmental proxy data are available, or for projecting the long-term impacts of future climate evolution on the performance of geological repositories for the disposal of radioactive wastes. However, due to the high computational requirements of current fully coupled general circulation models (GCMs), long-term simulations can generally only be performed with less complex models and/or at lower spatial resolution. In this study, we present novel long-term

  8. Emulation of long-term changes in global climate: Application to the late Pliocene and future

    KAUST Repository

    Lord, Natalie S.; Crucifix, Michel; Lunt, Dan J.; Thorne, Mike C.; Bounceur, Nabila; Dowsett, Harry; O& apos; Brien, Charlotte L.; Ridgwell, Andy

    2017-01-01

    Multi-millennial transient simulations of climate changes have a range of important applications, such as for investigating key geologic events and transitions for which high-resolution palaeoenvironmental proxy data are available, or for projecting the long-term impacts of future climate evolution on the performance of geological repositories for the disposal of radioactive wastes. However, due to the high computational requirements of current fully coupled general circulation models (GCMs), long-term simulations can generally only be performed with less complex models and/or at lower spatial resolution. In this study, we present novel long-term

  9. Long-term relationship between climate change and nomadic migration in historical China

    Directory of Open Access Journals (Sweden)

    Qing Pei

    2014-06-01

    Full Text Available We investigated the relationship between a 2000-year history of nomadic migration and climate change in historical China. By using updated data and statistical methods, the study solved several unanswered questions from past research about the relationship between climate change and the nomadic migration, especially over the long term and on a large spatial scale. The study used correlation analysis, multiple regression analysis, and Granger causality analysis to quantitatively verify the following causal pathway: climate change â†' nomadic migration â†' conflicts between pastoralists and agriculturalists. In the long term, precipitation was a statistically more influential factor on nomadic migration than temperature in historical China. How climate change affects the migration of nomadic minorities in the long term is theoretically explained based on the Push-Pull model as well as statistical evidence.

  10. Long-term effects of climate change on Europe's water resources

    NARCIS (Netherlands)

    Domnisoru, A.

    2006-01-01

    Climate variations from last century show a global warming trend. Evidence from the past reveals that the anthropogenic greenhouse effect caused changes in climate parameters (temperature, precipitation and evaporation) at the European scale as well. On long-term this might have essential impact on

  11. CLIMATE CHANGE: LONG-TERM TRENDS AND SHORT-TERM OSCILLATIONS

    Institute of Scientific and Technical Information of China (English)

    GAO Xin-quan; ZHANG Xin; QIAN Wei-hong

    2006-01-01

    Identifying the Northern Hemisphere (NH) temperature reconstruction and instrumental data for the past 1000 years shows that climate change in the last millennium includes long-term trends and various oscillations. Two long-term trends and the quasi-70-year oscillation were detected in the global temperature series for the last 140 years and the NH millennium series. One important feature was emphasized that temperature decreases slowly but it increases rapidly based on the analysis of different series. Benefits can be obtained of climate change from understanding various long-term trends and oscillations. Millennial temperature proxies from the natural climate system and time series of nonlinear model system are used in understanding the natural climate change and recognizing potential benefits by using the method of wavelet transform analysis. The results from numerical modeling show that major oscillations contained in numerical solutions on the interdecadal timescale are consistent with that of natural proxies. It seems that these oscillations in the climate change are not directly linked with the solar radiation as an external forcing. This investigation may conclude that the climate variability at the interdecadal timescale strongly depends on the internal nonlinear effects in the climate system.

  12. The long-term climate change task of the Hanford permanent isolation barrier development program

    International Nuclear Information System (INIS)

    1994-01-01

    The Hanford Site Permanent Isolation Barrier Development Program is developing an in-place disposal capability for low-level nuclear waste for the US Department of Energy at the Hanford Site in southeastern Washington State. Layered earthen and engineered barriers are being developed that will function in what is currently a semiarid environment (mean annual precipitation and temperature of 16 cm and 11.8 degrees C, respectively) for at least 1,000 yr by limiting the infiltration of water through the waste. The Long-Term Climate Change Task has specific goals of (1) obtaining defensible probabilistic projections of the long-term climate variability in the Hanford Site region at many different time scales into the future; (2) developing several test-case climate scenarios that bracket the range of potential future climate, including both greenhouse warming and cycling into another ice age; and (3) using the climate scenarios both to test and to model protective barrier performance. Results from the Carp Lake Pollen Coring Project indicate that for the last approximately 100,000 yr the Columbia River Basin's long-term range of mean annual precipitation ranged from 25%--50% below to 28% above modern levels, while temperature has ranged from 7 degrees C--10 degrees C below to 2 degrees C above modern levels. This long record provides confidence that such a range should bracket potential natural climate change even if the earth cycles back into another Ice Age in the next few millennia

  13. Dynamic response of land use and river nutrient concentration to long-term climatic changes.

    Science.gov (United States)

    Bussi, Gianbattista; Janes, Victoria; Whitehead, Paul G; Dadson, Simon J; Holman, Ian P

    2017-07-15

    The combined indirect and direct impacts of land use change and climate change on river water quality were assessed. A land use allocation model was used to evaluate the response of the catchment land use to long-term climatic changes. Its results were used to drive a water quality model and assess the impact of climatic alterations on freshwater nitrate and phosphorus concentrations. Climatic projections were employed to estimate the likelihood of such response. The River Thames catchment (UK) was used as a case-study. If land use is considered as static parameter, according to the model results, climate change alone should reduce the average nitrate concentration, although just by a small amount, by the 2050s in the Lower Thames, due to reduced runoff (and lower export of nitrate from agricultural soils) and increased instream denitrification, and should increase the average phosphorus concentration by 12% by the 2050s in the Lower Thames, due to a reduction of the effluent dilution capacity of the river flow. However, the results of this study also show that these long-term climatic alterations are likely to lead to a reduction in the arable land in the Thames, replaced by improved grassland, due to a decrease in agriculture profitability in the UK. Taking into account the dynamic co-evolution of land use with climate, the average nitrate concentration is expected to be decreased by around 6% by the 2050s in both the upper and the lower Thames, following the model results, and the average phosphorus concentration increased by 13% in the upper Thames and 5% in the lower Thames. On the long term (2080s), nitrate is expected to decrease by 9% and 8% (upper and lower Thames respectively) and phosphorus not to change in the upper thames and increase by 5% in the lower Thames. Copyright © 2017 Elsevier B.V. All rights reserved.

  14. The Impact of Long-Term Climate Change on Nitrogen Runoff at the Watershed Scale.

    Science.gov (United States)

    Dorley, J.; Duffy, C.; Arenas Amado, A.

    2017-12-01

    The impact of agricultural runoff is a major concern for water quality of mid-western streams. This concern is largely due to excessive use of agricultural fertilizer, a major source of nutrients in many Midwestern watersheds. In order to improve water quality in these watersheds, understanding the long-term trends in nutrient concentration and discharge is an important water quality problem. This study attempts to analyze the role of long-term temperature and precipitation on nitrate runoff in an agriculturally dominated watershed in Iowa. The approach attempts to establish the concentration-discharge (C-Q) signature for the watershed using time series analysis, frequency analysis and model simulation. The climate data is from the Intergovernmental Panel on Climate Change (IPCC), model GFDL-CM3 (Geophysical Fluid Dynamic Laboratory Coupled Model 3). The historical water quality data was made available by the IIHR-Hydroscience & Engineering at the University of Iowa for the clear creek watershed (CCW). The CCW is located in east-central Iowa. The CCW is representative of many Midwestern watersheds with humid-continental climate with predominantly agricultural land use. The study shows how long-term climate changes in temperature and precipitation affects the C-Q dynamics and how a relatively simple approach to data analysis and model projections can be applied to best management practices at the site.

  15. Long-term climatic change and sustainable ground water resources management

    International Nuclear Information System (INIS)

    Loaiciga, Hugo A

    2009-01-01

    Atmospheric concentrations of greenhouse gases (GHGs), prominently carbon dioxide (CO 2 ), methane (CH 4 ), nitrous oxide (N 2 O), and halocarbons, have risen from fossil-fuel combustion, deforestation, agriculture, and industry. There is currently heated national and international debate about the consequences of such increasing concentrations of GHGs on the Earth's climate, and, ultimately, on life and society in the world as we know it. This paper reviews (i) long-term patterns of climate change, secular climatic variability, and predicted population growth and their relation to water resources management, and, specifically, to ground water resources management, (ii) means available for mitigating and adapting to trends of climatic change and climatic variability and their impacts on ground water resources. Long-term (that is, over hundreds of millions of years), global-scale, climatic fluctuations are compared with more recent (in the Holocene) patterns of the global and regional climates to shed light on the meaning of rising mean surface temperature over the last century or so, especially in regions whose historical hydroclimatic records exhibit large inter-annual variability. One example of regional ground water resources response to global warming and population growth is presented.

  16. Effects of climate change on long-term population growth of pronghorn in an arid environment

    Science.gov (United States)

    Gedir, Jay V.; Cain, James W.; Harris, Grant; Turnbull, Trey T.

    2015-01-01

    Climate often drives ungulate population dynamics, and as climates change, some areas may become unsuitable for species persistence. Unraveling the relationships between climate and population dynamics, and projecting them across time, advances ecological understanding that informs and steers sustainable conservation for species. Using pronghorn (Antilocapra americana) as an ecological model, we used a Bayesian approach to analyze long-term population, precipitation, and temperature data from 18 populations in the southwestern United States. We determined which long-term (12 and 24 months) or short-term (gestation trimester and lactation period) climatic conditions best predicted annual rate of population growth (λ). We used these predictions to project population trends through 2090. Projections incorporated downscaled climatic data matched to pronghorn range for each population, given a high and a lower atmospheric CO2 concentration scenario. Since the 1990s, 15 of the pronghorn populations declined in abundance. Sixteen populations demonstrated a significant relationship between precipitation and λ, and in 13 of these, temperature was also significant. Precipitation predictors of λ were highly seasonal, with lactation being the most important period, followed by early and late gestation. The influence of temperature on λ was less seasonal than precipitation, and lacked a clear temporal pattern. The climatic projections indicated that all of these pronghorn populations would experience increased temperatures, while the direction and magnitude of precipitation had high population-specific variation. Models predicted that nine populations would be extirpated or approaching extirpation by 2090. Results were consistent across both atmospheric CO2 concentration scenarios, indicating robustness of trends irrespective of climatic severity. In the southwestern United States, the climate underpinning pronghorn populations is shifting, making conditions increasingly

  17. Incidence of climate on common frog breeding: Long-term and short-term changes

    Science.gov (United States)

    Neveu, André

    2009-09-01

    In Brittany (northwest France), the climate is showing a trend toward warming. This change is increasingly suspected to have a role in driving amphibian decline, but it is very difficult to determine at what level the climate affects the future of species. Recently, some studies have detected some direct effects on breeding phenology and indirect effects on energy allocation. The present study explores some of these effects on the common frog ( Rana temporaria) from 1984 to 2007. The results show two trends: a long-term change in breeding activities and a short-term influence due to the 2003 climatic anomaly. For the period of study, the start of egg-laying shows a precocity that was correlated with thermal conditions during the preceding 40 days as well as milder springs during the previous year. This degree of precocity is currently the highest found in Europe (+26.6 days). As a result of the 2003 heat wave, the clutch mean fecundity in 2004 was smaller than for other years, the fecundity rates were reduced and abortions were numerous (unlike other years). Moreover, young females were the smallest observed in recent years and some females seemed to exhibit a trade-off between fecundity and growth. Before or after egg-laying, female body condition and mean weight of mature ovules were both lower. The year 2005 appears as a transition period before the recovery in 2006-2007. The results show that climate warming endangers the vital rates of the common frog, while the 2003 climatic events seem more detrimental than the long-term warming trend.

  18. Assessing climate change and socio-economic uncertainties in long term management of water resources

    Science.gov (United States)

    Jahanshahi, Golnaz; Dawson, Richard; Walsh, Claire; Birkinshaw, Stephen; Glenis, Vassilis

    2015-04-01

    Long term management of water resources is challenging for decision makers given the range of uncertainties that exist. Such uncertainties are a function of long term drivers of change, such as climate, environmental loadings, demography, land use and other socio economic drivers. Impacts of climate change on frequency of extreme events such as drought make it a serious threat to water resources and water security. The release of probabilistic climate information, such as the UKCP09 scenarios, provides improved understanding of some uncertainties in climate models. This has motivated a more rigorous approach to dealing with other uncertainties in order to understand the sensitivity of investment decisions to future uncertainty and identify adaptation options that are as far as possible robust. We have developed and coupled a system of models that includes a weather generator, simulations of catchment hydrology, demand for water and the water resource system. This integrated model has been applied in the Thames catchment which supplies the city of London, UK. This region is one of the driest in the UK and hence sensitive to water availability. In addition, it is one of the fastest growing parts of the UK and plays an important economic role. Key uncertainties in long term water resources in the Thames catchment, many of which result from earth system processes, are identified and quantified. The implications of these uncertainties are explored using a combination of uncertainty analysis and sensitivity testing. The analysis shows considerable uncertainty in future rainfall, river flow and consequently water resource. For example, results indicate that by the 2050s, low flow (Q95) in the Thames catchment will range from -44 to +9% compared with the control scenario (1970s). Consequently, by the 2050s the average number of drought days are expected to increase 4-6 times relative to the 1970s. Uncertainties associated with urban growth increase these risks further

  19. Evaluation of long-term geological and climatic changes in the Spanish programme

    International Nuclear Information System (INIS)

    Torres, T.; Ortiz, J.E.; Cortes, A.; Delgado, A.

    2004-01-01

    The Bio-molecular Stratigraphy Laboratory of the Madrid School of Mines has been largely involved in the analysis of long-term paleo-environmental changes in the Iberian Peninsula during the Quaternary. Some of the research projects were UE funded: Paleo-climatological Revision of Climate Evolution in Western Mediterranean Region. Evaluation of Altered Scenarios, Evidence from Quaternary Infill Paleo-hydrogeology, Sequential Biosphere modelling function of Climate evolution models; Paleo-hydrogeological Data Analysis and Model Testing. Other projects were funded by the National Company for Radioactive Waste Management (ENRESA) and the Spanish Nuclear Safety Council (CSN): 'Paleo-climate reconstruction from Middle Pleistocene times through dating and isotopic analysis of tufa deposits'; 'Paleo-environmental evolution of the southern part of the Iberian Peninsula'; 'Paleo-climate'. On a minor scale the laboratory was also involved in the study of some argillaceous media: 'Organic Geochemistry of some deep Spanish argillaceous formations' and 'Effects of climatic change on the argillaceous series of the Duero and Ebro basins'. Here we will present some of the results obtained from tufa deposits analysis and paleo-environmental information from the Guadix-Baza Basin composite-stratigraphical-type-section study. (authors)

  20. The influence of long term climate change on net infiltration at Yucca Mountain, Nevada

    International Nuclear Information System (INIS)

    Flint, A.L.; Hevesi, J.A.; Flint, L.E.

    1993-01-01

    Net infiltration and recharge at Yucca Mountain, Nevada, a potential site for a high level nuclear waste repository, are determined both by the rock properties and past and future changes in climate. A 1-dimensional model was constructed to represent a borehole being drilled through the unsaturated zone. The rock properties were matched to the lithologies expected to be encountered in the borehole. As current paleoclimate theory assumes that 18 O increases with wetter and cooler global climates, a past climate scenario, built on depletion of 18 O from ocean sediments was used as a basis for climate change over the past 700,000 years. The climate change was simulated by assigning net infiltration values as a linear function of 18 O. Assuming the rock properties, lithologies, and climate scenarios are correct, simulations indicated that Yucca Mountain is not in steady state equilibrium at the surface ( 250 meters. Based on the cyclic climate inputs, the near surface is currently in a long term drying trend (for the last 3,000 years) yet recharge into the water table is continuing to occur at an average rate equivalent to the average input rate of the climate model, indicating that conditions at depth are damped out over very long time periods. The Paintbrush Tuff nonwelded units, positioned between the Tiva Canyon and Topopah Spring welded tuff Members, do not appear to act as a capillary barrier and therefore would not perch water. The low porosity vitric caprock and basal vitrophyre of the Topopah Spring Member, however, act as restrictive layers. The higher porosity rock directly above the caprock reduces the potential for the caprock to perch water leaving the basal vitrophyre as the most likely location for perched water to develop

  1. Non-climatic factors and long-term, continental-scale changes in seasonally frozen ground

    Science.gov (United States)

    Shiklomanov, Nikolay I.

    2012-03-01

    Numerous studies indicate that the northern high latitudes are experiencing an unprecedented rate of environmental change, including an increase in air temperatures (e.g. Serreze and Francis 2006), reduction of snow cover (e.g. Brown and Robinson 2011), ecosystem transformations and land cover changes (e.g. Callaghan et al 2011). Many of the potential environmental impacts of global warming in the high latitudes are associated with frozen ground, which occupies about 55% of the unglaciated land area in the northern hemisphere and consists of both permafrost and seasonally frozen ground. Frozen soils have a tremendous impact on hydrologic, climatic and biologic systems. Periodic freezing and thawing promote changes in soil structure, affect the surface and subsurface water cycle, and regulate the availability of nutrients in the soil for plants and biota that depend upon them. Freezing and thawing cycles can affect the decomposition of organic substances in the soil and greenhouse gas exchange between the atmosphere and land surface. Significant efforts have been devoted to permafrost-related studies, including the establishment of standardized observations (e.g. Romanovsky et al 2010, Shiklomanov et al 2008), modeling (e.g. Riseborough et al 2008), and climate-related feedback processes (e.g. Schuur et al 2008). Despite its vast extent and importance, seasonally frozen ground has received much less attention. One of the major obstacles in assessing changes in seasonally frozen ground is the lack of long-term data. In general, observations on soil temperature and freeze propagation are available for a limited area and involve a relatively short time period, precluding assessment of long-term, climate-driven change. A few known exceptions include shallow soil temperature and freeze/thaw depth observations conducted as part of the standard hydrometeorological monitoring system in China (e.g. Zhao et al 2004) and the Soviet Union/Russia (e.g. Gilichinsky et al 2000

  2. Emulation of long-term changes in global climate: application to the late Pliocene and future

    Directory of Open Access Journals (Sweden)

    N. S. Lord

    2017-11-01

    Full Text Available Multi-millennial transient simulations of climate changes have a range of important applications, such as for investigating key geologic events and transitions for which high-resolution palaeoenvironmental proxy data are available, or for projecting the long-term impacts of future climate evolution on the performance of geological repositories for the disposal of radioactive wastes. However, due to the high computational requirements of current fully coupled general circulation models (GCMs, long-term simulations can generally only be performed with less complex models and/or at lower spatial resolution. In this study, we present novel long-term continuous projections of climate evolution based on the output from GCMs, via the use of a statistical emulator. The emulator is calibrated using ensembles of GCM simulations, which have varying orbital configurations and atmospheric CO2 concentrations and enables a variety of investigations of long-term climate change to be conducted, which would not be possible with other modelling techniques on the same temporal and spatial scales. To illustrate the potential applications, we apply the emulator to the late Pliocene (by modelling surface air temperature – SAT, comparing its results with palaeo-proxy data for a number of global sites, and to the next 200 kyr (thousand years (by modelling SAT and precipitation. A range of CO2 scenarios are prescribed for each period. During the late Pliocene, we find that emulated SAT varies on an approximately precessional timescale, with evidence of increased obliquity response at times. A comparison of atmospheric CO2 concentration for this period, estimated using the proxy sea surface temperature (SST data from different sites and emulator results, finds that relatively similar CO2 concentrations are estimated based on sites at lower latitudes, whereas higher-latitude sites show larger discrepancies. In our second illustrative application, spanning the next

  3. The future of spaceborne altimetry. Oceans and climate change: A long-term strategy

    Science.gov (United States)

    Koblinsky, C. J. (Editor); Gaspar, P. (Editor); Lagerloef, G. (Editor)

    1992-01-01

    The ocean circulation and polar ice sheet volumes provide important memory and control functions in the global climate. Their long term variations are unknown and need to be understood before meaningful appraisals of climate change can be made. Satellite altimetry is the only method for providing global information on the ocean circulation and ice sheet volume. A robust altimeter measurement program is planned which will initiate global observations of the ocean circulation and polar ice sheets. In order to provide useful data about the climate, these measurements must be continued with unbroken coverage into the next century. Herein, past results of the role of the ocean in the climate system is summarized, near term goals are outlined, and requirements and options are presented for future altimeter missions. There are three basic scientific objectives for the program: ocean circulation; polar ice sheets; and mean sea level change. The greatest scientific benefit will be achieved with a series of dedicated high precision altimeter spacecraft, for which the choice of orbit parameters and system accuracy are unencumbered by requirements of companion instruments.

  4. The future of spaceborne altimetry. Oceans and climate change: A long-term strategy

    International Nuclear Information System (INIS)

    Koblinsky, C.J.; Gaspar, P.; Lagerloef, G.

    1992-03-01

    The ocean circulation and polar ice sheet volumes provide important memory and control functions in the global climate. Their long term variations are unknown and need to be understood before meaningful appraisals of climate change can be made. Satellite altimetry is the only method for providing global information on the ocean circulation and ice sheet volume. A robust altimeter measurement program is planned which will initiate global observations of the ocean circulation and polar ice sheets. In order to provide useful data about the climate, these measurements must be continued with unbroken coverage into the next century. Herein, past results of the role of the ocean in the climate system is summarized, near term goals are outlined, and requirements and options are presented for future altimeter missions. There are three basic scientific objectives for the program: ocean circulation; polar ice sheets; and mean sea level change. The greatest scientific benefit will be achieved with a series of dedicated high precision altimeter spacecraft, for which the choice of orbit parameters and system accuracy are unencumbered by requirements of companion instruments

  5. Assessing Forest Carbon Response to Climate Change and Disturbances Using Long-term Hydro-climatic Observations and Simulations

    Science.gov (United States)

    Trettin, C.; Dai, Z.; Amatya, D. M.

    2014-12-01

    Long-term climatic and hydrologic observations on the Santee Experimental Forest in the lower coastal plain of South Carolina were used to estimate long-term changes in hydrology and forest carbon dynamics for a pair of first-order watersheds. Over 70 years of climate data indicated that warming in this forest area in the last decades was faster than the global mean; 35+ years of hydrologic records showed that forest ecosystem succession three years following Hurricane Hugo caused a substantial change in the ratio of runoff to precipitation. The change in this relationship between the paired watersheds was attributed to altered evapotranspiration processes caused by greater abundance of pine in the treatment watershed and regeneration of the mixed hardwood-pine forest on the reference watershed. The long-term records and anomalous observations are highly valuable for reliable calibration and validation of hydrological and biogeochemical models capturing the effects of climate variability. We applied the hydrological model MIKESHE that showed that runoff and water table level are sensitive to global warming, and that the sustained warming trends can be expected to decrease stream discharge and lower the mean water table depth. The spatially-explicit biogeochemical model Forest-DNDC, validated using biomass measurements from the watersheds, was used to assess carbon dynamics in response to high resolution hydrologic observation data and simulation results. The simulations showed that the long-term spatiotemporal carbon dynamics, including biomass and fluxes of soil carbon dioxide and methane were highly regulated by disturbance regimes, climatic conditions and water table depth. The utility of linked-modeling framework demonstrated here to assess biogeochemical responses at the watershed scale suggests applications for assessing the consequences of climate change within an urbanizing forested landscape. The approach may also be applicable for validating large

  6. Scenarios of long-term farm structural change for application in climate change impact assessment

    NARCIS (Netherlands)

    Mandryk, M.; Reidsma, P.; Ittersum, van M.K.

    2012-01-01

    Towards 2050, climate change is one of the possible drivers that will change the farming landscape, but market, policy and technological development may be at least equally important. In the last decade, many studies assessed impacts of climate change and specific adaptation strategies. However,

  7. CLIMATE CHANGE. Long-term climate forcing by atmospheric oxygen concentrations.

    Science.gov (United States)

    Poulsen, Christopher J; Tabor, Clay; White, Joseph D

    2015-06-12

    The percentage of oxygen in Earth's atmosphere varied between 10% and 35% throughout the Phanerozoic. These changes have been linked to the evolution, radiation, and size of animals but have not been considered to affect climate. We conducted simulations showing that modulation of the partial pressure of oxygen (pO2), as a result of its contribution to atmospheric mass and density, influences the optical depth of the atmosphere. Under low pO2 and a reduced-density atmosphere, shortwave scattering by air molecules and clouds is less frequent, leading to a substantial increase in surface shortwave forcing. Through feedbacks involving latent heat fluxes to the atmosphere and marine stratus clouds, surface shortwave forcing drives increases in atmospheric water vapor and global precipitation, enhances greenhouse forcing, and raises global surface temperature. Our results implicate pO2 as an important factor in climate forcing throughout geologic time. Copyright © 2015, American Association for the Advancement of Science.

  8. Medium-long term soil resilience against different disturbances: wildfires, silvicultural treatments and climate change

    Science.gov (United States)

    Hedo de Santiago, Javier; Borja, Manuel Esteban Lucas; de las Heras, Jorge

    2016-04-01

    Soils of semiarid Mediterranean forest ecosystems are very fragile and sensitive to changes due to different anthropogenic and natural disturbances. The increasing vulnerability of semiarid lands within this world framework has generated growing awareness in the field of research, with highly intensified study into soils properties. One of the main problems of Mediterranean forests is wildfire disturbance. Fire should be considered more an ecological factor but, in contrast to the role of fire, it is now a closely related factor to human action. On the other hand, to improve the recovery of forest communities after fire, silvicultural treatments are needed and, for that matter, another disturbance is added to the ecosystem. By last, climate change is also affecting the fire regime increasing fire frequency and burned area, enhancing the destructiveness to Mediterranean ecosystems. After all of these three disturbances, changes in vegetation dynamics and soil properties are expected to occur due to the plant-soil feedback. Soil plays an essential role in the forest ecosystem's fertility and stability and specifically soil microorganisms, which accomplish reactions to release soil nutrients for vegetation development, for that is essential to enlarge knowledge about soil properties resilience in semiarid forest ecosystems. Physico-chemical and microbiological soil properties, and enzyme activities have been studied in two Aleppo pine forest stands that have suffered three disturbances: 1) a wildfire event, 2) silvicultural treatments (thinning) and 3) an artificial drought (simulating climate change) and results showed that soil recovered after 15 years. Final results showed that soils have been recovered from the three disturbances at the medium-long term.

  9. Testing causes for long-term changes in carbon cycling and climate during the early Paleogene

    Science.gov (United States)

    Komar, N.; Zeebe, R. E.; Dickens, G. R.

    2013-12-01

    The late Paleocene to the early Eocene (˜58-52 Ma) was marked by significant changes in global climate and carbon cycling. Among the evidence for these changes, stable isotope records reveal a prominent decrease of δ13C and δ18O (in both surface and deep ocean), indicating a reorganization in the long-term global carbon cycle and a long-term warming trend (˜4°C), respectively. Concurrently, deep-sea carbonate records at several sites indicate a deepening of the calcite compensation depth (CCD). Here, we investigate possible causes (e.g., increased volcanic degassing, decreased net organic burial, and accelerated dissociation of gas hydrate) for these observations, but from a new perspective. The basic model employed is a modified version of GEOCARB III. However, we have coupled this well-known geochemical model to LOSCAR, a model that enables simulation of seawater carbonate chemistry, the CCD, and ocean δ13C. We have also added a gas hydrate capacitor that can account for the storage and release of methane from the seafloor over millions of years. We further consider accurate input data (e.g., δ13C of carbonate) on a currently accepted time scale that spans an interval much longer than the perturbation. Several different scenarios are investigated with the goal of consistency amongst inferred changes in temperature, the CCD, and surface ocean and deep ocean δ13C. The results strongly suggest that a decrease in net organic carbon burial drove carbon cycle changes during the late Paleocene and early Eocene, although an increase in volcanic activity might have contributed. Importantly, a drop in net organic carbon burial may represent increased oxidation of previously deposited organic carbon, such as stored in peat or gas hydrates. The model successfully recreates trends in Earth surface warming, as inferred from δ18O records, the CCD, and δ13C. At the moment, however, our coupled modeling effort cannot reproduce the magnitude of change in all these

  10. Long-term planning in Small Islands Developing States under a changing climate

    Science.gov (United States)

    Rozenberg, J.

    2017-12-01

    This paper presents an analytical framework and decision-making tool tailored to Small Islands Developing States (SIDS), to help them address future climate change challenges. SIDS are a diverse group of countries but all characterized by insularity, geographic remoteness, small economy and population size. SIDS are highly exposed and vulnerable to natural disasters, with average annual losses between 1 and 10% of GDP depending on the country. Vulnerability in SIDS is worsened by poor development planning and the countries' limited ability to respond and manage the risks. Infrastructure is a large share of the fixed capital stock in SIDS, most infrastructure assets are highly critical due to the lack of redundancy in networks and they are often highly vulnerable to natural hazards. Remoteness means that when infrastructure assets are damaged, reconstruction costs are larger than anywhere else, which narrows fiscal space, which in turn leads to deferred maintenance problems and raises the vulnerability to future events. In this context, and with climate change worsening the challenges SIDS face at an uncertain pace and intensity, decision-makers and international donors have to answer difficult questions. Does it make sense to spend increasing amounts of money in infrastructure given the level of debts SIDS face and the economic losses resulting from the regular disruption of infrastructure assets? How should sectors be prioritized? Should long-term plans consider "migration with dignity" as a potential option, especially for low-lying atolls? To help answer these questions, methods for decision-making under deep uncertainty, which rely on large numbers of model runs to identify the vulnerabilities of strategies, are particularly appropriate. The small population size of SIDS and simplicity of their infrastructure networks allows building system models coupled with household surveys and testing a range of different policy options, including unconventional policies

  11. Minimizing the regrets of long-term urban floodplain management decisions under deeply uncertain climate change

    Science.gov (United States)

    Hecht, J. S.; Kirshen, P. H.; Vogel, R. M.

    2016-12-01

    Making long-term floodplain management decisions under uncertain climate change is a major urban planning challenge of the 21stcentury. To support these efforts, we introduce a screening-level optimization model that identifies adaptation portfolios by minimizing the regrets associated with their flood-control and damage costs under different climate change trajectories that are deeply uncertain, i.e. have probabilities that cannot be specified plausibly. This mixed integer program explicitly considers the coupled damage-reduction impacts of different floodwall designs and property-scale investments (first-floor elevation, wet floodproofing of basements, permanent retreat and insurance), recommends implementation schedules, and assesses impacts to stakeholders residing in three types of homes. An application to a stylized municipality illuminates many nonlinear system dynamics stemming from large fixed capital costs, infrastructure design thresholds, and discharge-depth-damage relationships. If stakeholders tolerate mild damage, floodwalls that fully protect a community from large design events are less cost-effective than portfolios featuring both smaller floodwalls and property-scale measures. Potential losses of property tax revenue from permanent retreat motivate municipal property-tax initiatives for adaptation financing. Yet, insurance incentives for first-floor elevation may discourage locally financed floodwalls, in turn making lower-income residents more vulnerable to severe flooding. A budget constraint analysis underscores the benefits of flexible floodwall designs with low incremental expansion costs while near-optimal solutions demonstrate the scheduling flexibility of many property-scale measures. Finally, an equity analysis shows the importance of evaluating the overpayment and under-design regrets of recommended adaptation portfolios for each stakeholder and contrasts them to single-scenario model results.

  12. Long-term vegetation changes in a temperate forest impacted by climate change

    Science.gov (United States)

    Lauren E. Oakes; Paul E. Hennon; Kevin L. O' Hara; Rodolfo Dirzo

    2014-01-01

    Pervasive forest mortality is expected to increase in future decades as a result of increasing temperatures. Climate-induced forest dieback can have consequences on ecosystem services, potentially mediated by changes in forest structure and understory community composition that emerge in response to tree death. Although many dieback events around the world have been...

  13. Long-term corporate climate change targets: What could they deliver?

    International Nuclear Information System (INIS)

    Gouldson, Andy; Sullivan, Rory

    2013-01-01

    Highlights: ► Increasingly, companies are setting long-term greenhouse gas emission reduction targets. ► Many of these corporate targets appear to exceed those being set by national governments. ► Achieving these corporate targets relies on energy prices remaining high. ► Weaknesses in corporate reporting make it difficult to tell whether targets are being achieved. -- Abstract: Driven by the rising cost of energy, stakeholder pressure and the expectation that governments will continue to implement policy measures directed at reducing greenhouse gas emissions, an increasing number of companies have set targets to reduce their greenhouse gas emissions. These commitments raise two important questions. The first is whether they can be considered – individually or collectively – to be an appropriate response to the threat presented by climate change. The second is whether they are dependable; that is, can policy makers and other stakeholders can rely on companies to deliver on the commitments that they have made? This article examines these two questions using the case of the UK supermarket sector to illustrate and explain the issues at stake and, more generally, to examine the contribution that these types of voluntary commitments can make to wider public policy goals on climate change. The reasons for focusing on the UK supermarket sector are that the companies in this sector are some of the largest retailers in the world, they are significant emitters (their direct emissions account for 0.9% of UK carbon emissions, and some indications suggest that their indirect emissions account for ten times as much), and they are less heavily regulated that other sectors with comparable carbon footprints. The article concludes that the targets being set voluntarily by companies in this sector align with, or may even exceed, the climate change policy goals being set by national governments. Moreover, the article concludes that the companies targets are plausible and

  14. Long-term dataset on aquatic responses to concurrent climate change and recovery from acidification

    Science.gov (United States)

    Leach, Taylor H.; Winslow, Luke A.; Acker, Frank W.; Bloomfield, Jay A.; Boylen, Charles W.; Bukaveckas, Paul A.; Charles, Donald F.; Daniels, Robert A.; Driscoll, Charles T.; Eichler, Lawrence W.; Farrell, Jeremy L.; Funk, Clara S.; Goodrich, Christine A.; Michelena, Toby M.; Nierzwicki-Bauer, Sandra A.; Roy, Karen M.; Shaw, William H.; Sutherland, James W.; Swinton, Mark W.; Winkler, David A.; Rose, Kevin C.

    2018-04-01

    Concurrent regional and global environmental changes are affecting freshwater ecosystems. Decadal-scale data on lake ecosystems that can describe processes affected by these changes are important as multiple stressors often interact to alter the trajectory of key ecological phenomena in complex ways. Due to the practical challenges associated with long-term data collections, the majority of existing long-term data sets focus on only a small number of lakes or few response variables. Here we present physical, chemical, and biological data from 28 lakes in the Adirondack Mountains of northern New York State. These data span the period from 1994-2012 and harmonize multiple open and as-yet unpublished data sources. The dataset creation is reproducible and transparent; R code and all original files used to create the dataset are provided in an appendix. This dataset will be useful for examining ecological change in lakes undergoing multiple stressors.

  15. Ecosystem processes and human influences regulate streamflow response to climate change at long-term ecological research sites

    Science.gov (United States)

    Julia A. Jones; Irena F. Creed; Kendra L. Hatcher; Robert J. Warren; Mary Beth Adams; Melinda H. Benson; Emery Boose; Warren A. Brown; John L. Campbell; Alan Covich; David W. Clow; Clifford N. Dahm; Kelly Elder; Chelcy R. Ford; Nancy B. Grimm; Donald L Henshaw; Kelli L. Larson; Evan S. Miles; Kathleen M. Miles; Stephen D. Sebestyen; Adam T. Spargo; Asa B. Stone; James M. Vose; Mark W. Williams

    2012-01-01

    Analyses of long-term records at 35 headwater basins in the United States and Canada indicate that climate change effects on streamflow are not as clear as might be expected, perhaps because of ecosystem processes and human influences. Evapotranspiration was higher than was predicted by temperature in water-surplus ecosystems and lower than was predicted in water-...

  16. Advice on a long-term strategy on energy and climate change

    International Nuclear Information System (INIS)

    2006-06-01

    A study was conducted to examine how climate change would affect Canada's economy and environment, with a focus on what a low carbon future might look like for Canada over the next 45 years. Two questions formed the basis of this research that examined how Canada can protect and enhance its national interest with regard to energy and climate change issues between now and the mid-twenty first century and what Canada currently needs to do in order to achieve this. A scenario was developed as part of this study in order to demonstrate one way in which Canada can achieve a significant reduction in energy related GHG emissions by 2050. For illustrative purposes, it was necessary to have a quantifiable definition of what a significant reduction would look like, and therefore, it was decided that a long-term domestic reduction of energy-related GHG emissions by 60 per cent by 2050 would be used as it is roughly consistent with similar targets adopted or being considered by other OECD countries. The scope of this analysis covered energy-related GHG emissions such as carbon dioxide, methane and nitrous oxide that result from the production and consumption of fossil fuels. The paper provided a summary of key findings from the study and discussed Canada's unique environmental challenges. Study characteristics, scope of the analysis and assumptions were also identified. A 60 per cent GHG reduction wedge diagram was provided to illustrate the scenario under consideration. Strategic priorities were also presented identifying where transformations will need to occur. These priorities include energy efficiency improvements, carbon capture and sequestration in the oil and gas sector, and electricity generation. The paper also provided several conclusions and next steps. One of the principal conclusions was that there can be a domestic solution to making significant GHG reductions by mid-century, but significant reductions can be achieved only if energy is used more efficiently and

  17. Diverse perspectives on governance on the very long term. Biodiversity, climatic change, CO2 storage, radioactive wastes, space wastes

    International Nuclear Information System (INIS)

    Boeuf, Gilles; Gouyon, Pierre Henry; Rollinger, Francois; Besnus, Francois; Heriard Dubreuil, Gilles; Dahan, Amy; Alby, Fernand; Arnould, Jacques; Fabriol, Hubert; Hoummady, Moussa; Demarcq, Francois; Farret, Regis; Hubert, Philippe; Weber, Jacques; Charton, Patrick; Boissier, Fabrice; Lopez, Mirelle; Devisse, Jean-Jacques; Mathy, Sandrine; Hourcade, Jean-Charles; Le Roux, Xavier; Bourcier, Danielle; Roure, Francoise; Henry, Claude; Bartet, Jean Hughes; Calame, Mathieu; Biteau, Benoit; Kastler, Guy; Ducret, Pierre; Berest, Pierre; Charron, Sylvie; Clin, Francois; Gadbois, Serge; Gueritte, Michel; Heriard-Dubreuil, Bertrand; Laville, Bettina; Marie, Michel; Marignac, Yves; Ollagnon, Henry; Pelegrin, Flora; Roure, Francoise; Rouyer, Michel; Schellenberger, Thomas; Toussaint, Jean-Francois

    2013-03-01

    This bibliographical note contains the program of a workshop and a presentation of a book based on the contributions to this workshop proposed by experts, representatives of institutional bodies and associations, or local representatives. This workshop addressed the issue of the governance on the very long term with respect to the management of resources such as climate, geology, biodiversity or space. How to make a possible usage of these resources while ensuring their protection and durability? What are the solutions or new challenges are raising these usages on the very long term? The first part addresses the main challenges and ethical issues for governance on the very long term for each of the examined topics: biodiversity, climatic change, CO 2 storage, radioactive waste storage, and space debris). The next parts propose contributions from different origins and disciplines, present relevant data, and report evidences

  18. Long-term forest resilience to climate change indicated by mortality, regeneration, and growth in semiarid southern Siberia.

    Science.gov (United States)

    Xu, Chongyang; Liu, Hongyan; Anenkhonov, Oleg A; Korolyuk, Andrey Yu; Sandanov, Denis V; Balsanova, Larisa D; Naidanov, Bulat B; Wu, Xiuchen

    2017-06-01

    Several studies have documented that regional climate warming and the resulting increase in drought stress have triggered increased tree mortality in semiarid forests with unavoidable impacts on regional and global carbon sequestration. Although climate warming is projected to continue into the future, studies examining long-term resilience of semiarid forests against climate change are limited. In this study, long-term forest resilience was defined as the capacity of forest recruitment to compensate for losses from mortality. We observed an obvious change in long-term forest resilience along a local aridity gradient by reconstructing tree growth trend and disturbance history and investigating postdisturbance regeneration in semiarid forests in southern Siberia. In our study, with increased severity of local aridity, forests became vulnerable to drought stress, and regeneration first accelerated and then ceased. Radial growth of trees during 1900-2012 was also relatively stable on the moderately arid site. Furthermore, we found that smaller forest patches always have relatively weaker resilience under the same climatic conditions. Our results imply a relatively higher resilience in arid timberline forest patches than in continuous forests; however, further climate warming and increased drought could possibly cause the disappearance of small forest patches around the arid tree line. This study sheds light on climate change adaptation and provides insight into managing vulnerable semiarid forests. © 2016 John Wiley & Sons Ltd.

  19. A three-component analytic model of long-term climate change

    Science.gov (United States)

    Pratt, V. R.

    2011-12-01

    On the premise that fast climate fluctuations up to and including the 11-year solar cycle play a negligible role in long-term climate forecasting, we remove these from the 160-year HADCRUT3 global land-sea temperature record and model the result as the sum of a log-raised-exponential (log(b+exp(t))) and two sine waves of respective periods 56 and 75 years coinciding in phase in 1925. The latter two can be understood equivalently as a 62-year-period "carrier" modulated with a 440-year period that peaked in 1925 and vanished in 1705. This model gives an excellent fit, explaining 98% of the variance (r^2) of long-term climate over the 160 years. We derive the first component as the composition of Arrhenius's 1896 logarithmic dependence of surface temperature on CO2 with Hofmann's 2009 raised-exponential dependence of CO2 on time, but interpret its fit to the data as the net anthropogenic contribution incorporating all greenhouse and aerosol emissions and relevant feedbacks, bearing in mind the rapid growth in both population and technology. The 56-year oscillation matches the largest component of the Atlantic Multidecadal Oscillation, while the 75-year one is near an oscillation often judged to be in the vicinity of 70 years. The expected 1705 cancellation is about two decades earlier than suggested by Gray et al's tree-ring proxy for the AMO during 1567-1990 [Gray GPL 31, L12205]. While there is no consensus on the origin of ocean oscillations, the oscillations in geomagnetic secular variation noted by Nagata and Rimitake in 1963 and Slaucitajs and Winch in 1965, of respective periods 77 years and 61 years, correspond strikingly with our 76-year oscillation and 62-year "carrier." This model has a number of benefits. Simplicity. It is easily explained to a lay audience in response to the frequently voiced concern that the temperature record is poorly correlated with the CO2 record alone. It shows that the transition from natural to anthropogenic influences on long-term

  20. Long Term Fuel Sustainable Fission Energy Perspective Relevant for Combating Climate Change

    International Nuclear Information System (INIS)

    Knapp, V.; Matijevic, M.; Pevec, D.; Crnobrnja, B.; Lale, D.

    2016-01-01

    In recent research we outlined climate relevant and immediately available proven light water nuclear strategy with a potential to contribute essentially and timely to reduction of carbon dioxide emission to the year 2065. We consider in this paper what is the perspective of fission energy after that year should its contribution be needed. Singling out two technologies with long term perspective which need no or small amounts of uranium, fast breeders and molten salt thorium reactors, we consider their main technical and safety characteristics. In both of these technologies it is essential to have starter nuclides as neither U238 nor Th232 are fissile. We investigated whether plutonium from spent fuel of light water reactors generated to the year 2065 would be present in quantities sufficient to continue operation on the same or similar level in both technologies. However in operational safety, proliferation risks, waste production, in our judgement we must give preference to thorium technology, if it would be ready in second half of the century.(author).

  1. Consideration of environmental change in the safety evaluation: Long-term climate scenarios in the Iberian Peninsula

    International Nuclear Information System (INIS)

    Recreo Jimenez, F.; Ruiz Rivas, C.

    1997-01-01

    The main objective of this report is twofold. On the one hand, to define the most likely sequences of climate states in the Iberian Peninsula for a period of 125 Ka into the future, to the next interglacial stage, 125 Ka AP; on the other hand, to establish potential climate scenarios during such a period of time determining also the variability ranges of primary climate and climate-related variables of interest to the post-closure performance assessment and underground repository safety evaluations. The report reviews the potential effects of environmental changes on the performance of underground radioactive waste repositories, emphasizing the consideration given to long-term climatic changes in radioactive waste disposal system safety evaluations. (Author)

  2. Climate Change Impacts on pricing Long-Term Flood Insurance: A Comprehensive Study for the Netherlands

    NARCIS (Netherlands)

    Aerts, J.C.J.H.; Botzen, W.J.W.

    2011-01-01

    Recently long-term flood insurance contracts with a duration of 5, 10 or 15 years have been proposed as a solution for covering flood risk and mitigating increasing flood losses. Establishing a long-term relation between the policyholder and the insurer can provide better incentives to reduce risk

  3. Impact of long-term climate change on a deep geological repository for spent nuclear fuel

    International Nuclear Information System (INIS)

    Boulton, G.S.; Kautsky, U.; Moren, L.; Wallroth, T.

    2001-05-01

    The radioactivity of spent nuclear fuel will decay over a period of time (100,000 years or longer) in which we expect major environmental change. Climatically driven changes such as glaciation, permafrost and changes in sea level will affect the subsurface environment and must therefore be considered in performance and safety assessments. We regard the state of climate to be determined by the climate system, comprising the atmosphere, the biosphere, the oceans, the ice sheets and the surface of the lithosphere. Climate can change as a consequence of external forcing or as a consequence of the internal dynamics. The changes in the past show a complex cyclical pattern with repetitive periodicities and magnitudes of change. On the relatively long time scale which is of concern in this report climate changes are believed to be triggered by changes in insolation due to cyclical changes in the earth's orbit around the sun. This is referred to as the Milankovitch theory or the astronomical climate theory. A brief review of our knowledge of the climate system, proxy records and observations of past climate change is presented in the report. The most extreme departures from modern environmental conditions in Sweden have occurred during the cold, glacial cycles with ice sheets covering the whole of Sweden. As part of SKB's palaeohydrogeological research programme a time-dependent, thermo-mechanically coupled model of ice sheet behaviour has been developed in order to simulate past fluctuations of the Scandinavian ice sheet and forecast its future. The ice sheet model can calculate the temperature field and isostatic response of the underlying bedrock, subglacial and proglacial permafrost and the subglacial melt rates. By connecting the glaciation model with hydrogeological and rock mechanical models, the response of the subsurface to climate change can be investigated. In this report the climate-driven environmental changes are represented as a series of successive climate

  4. Impact of long-term climate change on a deep geological repository for spent nuclear fuel

    Energy Technology Data Exchange (ETDEWEB)

    Boulton, G.S. [Edinburgh Univ. (United Kingdom); Kautsky, U.; Moren, L. [Swedish Nuclear Fuel and Waste Management Co., Stockholm (Sweden); Wallroth, T. [Bergab Consulting Geologists (Sweden)

    2001-05-01

    The radioactivity of spent nuclear fuel will decay over a period of time (100,000 years or longer) in which we expect major environmental change. Climatically driven changes such as glaciation, permafrost and changes in sea level will affect the subsurface environment and must therefore be considered in performance and safety assessments. We regard the state of climate to be determined by the climate system, comprising the atmosphere, the biosphere, the oceans, the ice sheets and the surface of the lithosphere. Climate can change as a consequence of external forcing or as a consequence of the internal dynamics. The changes in the past show a complex cyclical pattern with repetitive periodicities and magnitudes of change. On the relatively long time scale which is of concern in this report climate changes are believed to be triggered by changes in insolation due to cyclical changes in the earth's orbit around the sun. This is referred to as the Milankovitch theory or the astronomical climate theory. A brief review of our knowledge of the climate system, proxy records and observations of past climate change is presented in the report. The most extreme departures from modern environmental conditions in Sweden have occurred during the cold, glacial cycles with ice sheets covering the whole of Sweden. As part of SKB's palaeohydrogeological research programme a time-dependent, thermo-mechanically coupled model of ice sheet behaviour has been developed in order to simulate past fluctuations of the Scandinavian ice sheet and forecast its future. The ice sheet model can calculate the temperature field and isostatic response of the underlying bedrock, subglacial and proglacial permafrost and the subglacial melt rates. By connecting the glaciation model with hydrogeological and rock mechanical models, the response of the subsurface to climate change can be investigated. In this report the climate-driven environmental changes are represented as a series of successive

  5. Assessment of long-term effects of climate change on biodiversity and vulnerability of terrestrial ecosystems

    Energy Technology Data Exchange (ETDEWEB)

    Oene, H.; Berendse, F.; De Kovel, C.G.F. [Nature Consevation and Plant Ecology Group, Wageningen University, Wageningen (Netherlands); Alkemade, J.R.M.; Bakkenes, M.; Ihle, F. [National Institute of Public Health and the Environment RIVM, Bilthoven (Netherlands)

    1999-07-01

    The aim of this project was to analyze the effects of climatic change on plant species diversity and ecosystem functioning. The direct effects of climatic change on plant species diversity are analyzed using a species based probabilistic Model (EUROMOVE) that relates the probability of occurrence of ca 1400 European plant species to climatic variables as the mean temperature of the coldest month, the effective temperature sum, the annual precipitation, the annual potential and actual evapotranspiration, the length of the growing season, and the mean growing season temperature. The indirect effects of raised C0{sub 2} levels and increased temperatures on ecosystem functioning and the consequences of these indirect effects for plant diversity are analyzed by combining a mechanistic simulation model (NUCOM) with regression models. NUCOM predicts the effects of environmental changes on dominant plant species composition and ecosystem variables. The predicted ecosystem variables are linked to plant species diversity of subordinate species by regression models, using Ellenberg indices for N availability, soil acidity, soil moisture, and light intensity. With these two approaches, the consequences of climatic change scenarios (IPCC Baseline A, IPCC Stabilization 450) and N deposition scenarios (reduced, constant) are analyzed for Europe (EUROMOVE) and part of the Netherlands (NUCOM). The results showed that the direct effects of climatic change may have large impact on plant species diversity and distribution. The indirect effects of climatic change on plant diversity appeared minor but effects of changes in soil moisture are not included. Other environmental changes like eutrofication and human impact have large effect on ecosystem variables and plant species diversity. Reductions in nitrogen emission have a positive effect but take time to become apparent. 49 refs.

  6. Long-term climate change assessment study plan for the Hanford Site permanent isolation Barrier Development Program

    International Nuclear Information System (INIS)

    Petersen, K.L.; Chatters, J.C.; Waugh, W.J.

    1992-07-01

    The Hanford Site Permanent Isolation Barrier Development Program (Barrier Development Program) was organized to develop the technology needed to provide an in-place disposal capability for the Hanford Site (Adams and Wing 1986; Wig and Gee 1990). The goal of the Barrier Development Program is to provide defensible evidence that final barrier design(s) will adequately control water infiltration; plant and animal intrusion; and wind and water erosion for a minimum of 1,000 yr and isolate wastes from the accessible environment and warm inadvertent human intruders using markers. This document describes the long-term climate change studies planned to support the Barrier Development Program. The plan outlines a multi-year and multi-discipline approach to assess long-term climate change issues and to help optimize the design of the permanent isolation barriers. A multi-disciplinary approach to climatic data acquisition will be responsible for obtaining needed information for concurrent barrier tasks and for developing a local climate forecast model. This model will couple past climate patterns with models of regional and global climate drivers to provide bounding conditions for barrier performance assessment analyses

  7. Climate change and the long-term viability of the World's busiest heavy haul ice road

    Science.gov (United States)

    Mullan, Donal; Swindles, Graeme; Patterson, Tim; Galloway, Jennifer; Macumber, Andrew; Falck, Hendrik; Crossley, Laura; Chen, Jie; Pisaric, Michael

    2017-08-01

    Climate models project that the northern high latitudes will warm at a rate in excess of the global mean. This will pose severe problems for Arctic and sub-Arctic infrastructure dependent on maintaining low temperatures for structural integrity. This is the case for the economically important Tibbitt to Contwoyto Winter Road (TCWR)—the world's busiest heavy haul ice road, spanning 400 km across mostly frozen lakes within the Northwest Territories of Canada. In this study, future climate scenarios are developed for the region using statistical downscaling methods. In addition, changes in lake ice thickness are projected based on historical relationships between measured ice thickness and air temperatures. These projections are used to infer the theoretical operational dates of the TCWR based on weight limits for trucks on the ice. Results across three climate models driven by four RCPs reveal a considerable warming trend over the coming decades. Projected changes in ice thickness reveal a trend towards thinner lake ice and a reduced time window when lake ice is at sufficient thickness to support trucks on the ice road, driven by increasing future temperatures. Given the uncertainties inherent in climate modelling and the resultant projections, caution should be exercised in interpreting the magnitude of these scenarios. More certain is the direction of change, with a clear trend towards winter warming that will reduce the operation time window of the TCWR. This illustrates the need for planners and policymakers to consider future changes in climate when planning annual haulage along the TCWR.

  8. Long-term persistence, density dependence and effects of climate change on rosyside dace (Cyprinidae)

    Science.gov (United States)

    Gary D. Grossman; Gary Sundin; Robert E. Ratajczak

    2016-01-01

    SummaryWe used long-term population data for rosyside dace (Clinostomus funduloides), a numerically dominant member of a stochastically organised fish assemblage, to evaluate the relative importance of density-dependent and density-independent processes to population...

  9. Incorporating long-term climate change in performance assessment for the Waste Isolation Pilot Plant

    International Nuclear Information System (INIS)

    Swift, P.N.; Baker, B.L.; Economy, K.; Garner, J.W.; Helton, J.C.; Rudeen, D.K.

    1993-01-01

    The United States Department of Energy (DOE) is developing the Waste Isolation Pilot Plant (WIPP) in southeastern New Mexico for the disposal of transuranic wastes generated by defense programs. Applicable regulations (40 CFR 191) require the DOE to evaluate disposal-system performance for 10,000 yr. Climatic changes may affect performance by altering groundwater flow. Paleoclimatic data from southeastern New Mexico and the surrounding area indicate that the wettest and coolest Quaternary climate at the site can be represented by that at the last glacial maximum, when mean annual precipitation was approximately twice that of the present. The hottest and driest climates have been similar to that of the present. The regularity of global glacial cycles during the late Pleistocene confirms that the climate of the last glacial maximum is suitable for use as a cooler and wetter bound for variability during the next 10,000 yr. Climate variability is incorporated into groundwater-flow modeling for WIPP PA by causing hydraulic head in a portion of the model-domain boundary to rise to the ground surface with hypothetical increases in precipitation during the next 10,000 yr. Variability in modeled disposal-system performance introduced by allowing head values to vary over this range is insignificant compared to variability resulting from other causes, including incomplete understanding of transport processes. Preliminary performance assessments suggest that climate variability will not affect regulatory compliance

  10. Incorporating long-term climate change in performance assessment for the Waste Isolation Pilot Plant

    International Nuclear Information System (INIS)

    Swift, P.N.; Baker, B.L.; Economy, K.; Garner, J.W.; Helton, J.C.; Rudeen, D.K.

    1994-03-01

    The United States Department of Energy (DOE) is developing the Waste Isolation Pilot Plant (WIPP) in southeastern New Mexico for the disposal of transuranic wastes generated by defense programs. Applicable regulations (40 CFR 191) require the DOE to evaluate disposal-system performance for 10,000 yr. Climatic changes may affect performance by altering groundwater flow. Paleoclimatic data from southeastern New Mexico and the surrounding area indicate that the wettest and coolest Quaternary climate at the site can be represented by that at the last glacial maximum, when mean annual precipitation was approximately twice that of the present. The hottest and driest climates have been similar to that of the present. The regularity of global glacial cycles during the late Pleistocene confirms that the climate of the last glacial maximum is suitable for use as a cooler and wetter bound for variability during the next 10,000 yr. Climate variability is incorporated into groundwater-flow modeling for WIPP PA by causing hydraulic head in a portion of the model-domain boundary to rise to the ground surface with hypothetical increases in precipitation during the next 10,000 yr. Variability in modeled disposal-system performance introduced by allowing had values to vary over this range is insignificant compared to variability resulting from other causes, including incomplete understanding of transport processes. Preliminary performance assessments suggest that climate variability will not affect regulatory compliance

  11. Future climate change is predicted to shift long-term persistence zones in the cold-temperate kelp Laminaria hyperborea.

    Science.gov (United States)

    Assis, Jorge; Lucas, Ana Vaz; Bárbara, Ignacio; Serrão, Ester Álvares

    2016-02-01

    Global climate change is shifting species distributions worldwide. At rear edges (warmer, low latitude range margins), the consequences of small variations in environmental conditions can be magnified, producing large negative effects on species ranges. A major outcome of shifts in distributions that only recently received attention is the potential to reduce the levels of intra-specific diversity and consequently the global evolutionary and adaptive capacity of species to face novel disturbances. This is particularly important for low dispersal marine species, such as kelps, that generally retain high and unique genetic diversity at rear ranges resulting from long-term persistence, while ranges shifts during climatic glacial/interglacial cycles. Using ecological niche modelling, we (1) infer the major environmental forces shaping the distribution of a cold-temperate kelp, Laminaria hyperborea (Gunnerus) Foslie, and we (2) predict the effect of past climate changes in shaping regions of long-term persistence (i.e., climatic refugia), where this species might hypothetically harbour higher genetic diversity given the absence of bottlenecks and local extinctions over the long term. We further (3) assessed the consequences of future climate for the fate of L. hyperborea using different scenarios of greenhouse gas emissions (RCP 2.6 and RCP 8.5). Results show NW Iberia, SW Ireland and W English Channel, Faroe Islands and S Iceland, as regions where L. hyperborea may have persisted during past climate extremes until present day. All predictions for the future showed expansions to northern territories coupled with the significant loss of suitable habitats at low latitude range margins, where long-term persistence was inferred (e.g., NW Iberia). This pattern was particularly evident in the most agressive scenario of climate change (RCP 8.5), likely driving major biodiversity loss, changes in ecosystem functioning and the impoverishment of the global gene pool of L

  12. Long-term climate change impacts on agricultural productivity in eastern China

    Energy Technology Data Exchange (ETDEWEB)

    Chavas, Daniel R.; Izaurralde, Roberto C.; Thomson, Allison M.; Gao, Xuejie

    2009-06-15

    Increasing atmospheric greenhouse gas concentrations are expected to induce significant climate change over the next century and beyond, but the impacts on society remain highly uncertain. This work examines potential climate change impacts on the productivity of five major crops in northeastern China: canola, corn, potato, rice, and winter wheat. In addition to determining domain-wide trends, the objective is to identify vulnerable and emergent regions under future climate conditions, defined as having a greater than 10% decrease and increase in productivity, respectively. Data from the ICTP RegCM3 regional climate model for baseline (1961-1990) and future (2071-2100) periods under A2 scenario conditions are used as input in the EPIC agro-ecosystem simulation model in the domain [30ºN, 108ºE] to [42ºN, 123ºE]. Simulations are performed with and without the enhanced CO2 fertilization effect. Results indicate that aggregate potential productivity (i.e. if the crop is grown everywhere) increases 6.5% for rice, 8.3% for canola, 18.6% for corn, 22.9% for potato, and 24.9% for winter wheat, although with significant spatial variability for each crop. However, absent the enhanced CO2 fertilization effect, potential productivity declines in all cases ranging from 2.5-12%. Interannual yield variability remains constant or declines in all cases except rice. Climate variables are found to be more significant drivers of simulated yield changes than changes in soil properties, except in the case of potato production in the northwest where the effects of wind erosion are more significant. Overall, in the future period corn and winter wheat benefit significantly in the North China Plain, rice remains dominant in the southeast and emerges in the northeast, potato and corn yields become viable in the northwest, and potato yields suffer in the southwest with no other crop emerging as a clear beneficiary from among those simulated in this study.

  13. Climate change and population dynamics at the tree line: the importance of long-term studies

    Directory of Open Access Journals (Sweden)

    Anfodillo T

    2007-01-01

    Full Text Available Temperature-limited ecosystems are believed to be extremely sensitive to global warming and the upward treeline migration is one of the most relevant phenomenon. Long term monitoring of demographic trends appears essential in order to understand possible effects of higher temperatures on cold ecosystems. Long-term monitoring of natality and mortality of a Pinus sylvestris population in the Swedish Scandes from 1973 to 2005 (Kullman 2007 showed that number of trees increased in the study plots due to higher natality rate, especially in the last decade. This reverses a natural trend of treeline decline and recession occurred in the past.

  14. Long-term changes in abundances of Sonoran Desert lizards reveal complex responses to climatic variation.

    Science.gov (United States)

    Flesch, Aaron D; Rosen, Philip C; Holm, Peter

    2017-12-01

    Understanding how climatic variation affects animal populations and communities is essential for addressing threats posed by climate change, especially in systems where impacts are projected to be high. We evaluated abundance dynamics of five common species of diurnal lizards over 25 years in a Sonoran Desert transition zone where precipitation decreased and temperature increased across time, and assessed hypotheses for the influence of climatic flux on spatiotemporal variation in abundances. We repeatedly surveyed lizards in spring and summer of each year at up to 32 sites, and used hierarchical mixture models to estimate detection probabilities, abundances, and population growth rates. Among terrestrial species, abundances of a short-lived, winter-spring breeder increased markedly by an estimated 237%-285% across time, while two larger spring-summer breeders with higher thermal preferences declined by up to 64%. Abundances of two arboreal species that occupy shaded and thus sheltered microhabitats fluctuated but did not decline systematically. Abundances of all species increased with precipitation at short lag times (1-1.5 years) likely due to enhanced food availability, but often declined after periods of high precipitation at longer lag times (2-4 years) likely due to predation and other biotic pressures. Although rising maximum daily temperatures (T max ) are expected to drive global declines of lizards, associations with T max were variable and weak for most species. Instead, abundances of all species declined with rising daily minimum temperatures, suggesting degradation of cool refugia imposed widespread metabolic or other costs. Our results suggest climate warming and drying are having major impacts on lizard communities by driving declines in species with traits that augment exposure to abiotic extremes and by modifying species interactions. The complexity of patterns we report indicates that evaluating and responding to the influence of climate change

  15. Long-term effects of climate and land cover change on freshwater provision in the tropical Andes

    Science.gov (United States)

    Molina, A.; Vanacker, V.; Brisson, E.; Mora, D.; Balthazar, V.

    2015-06-01

    Andean headwater catchments play a pivotal role to supply fresh water for downstream water users. However, few long-term studies exist on the relative importance of climate change and direct anthropogenic perturbations on flow regimes. In this paper, we assess multi-decadal change in freshwater provision based on long time series (1974-2008) of hydrometeorological data and land cover reconstructions for a 282 km2 catchment located in the tropical Andes. Three main land cover change trajectories can be distinguished: (1) rapid decline of native vegetation in montane forest and páramo ecosystems in ~1/5 or 20% of the catchment area, (2) expansion of agricultural land by 14% of the catchment area, (3) afforestation of 12% of native páramo grasslands with exotic tree species in recent years. Given the strong temporal variability of precipitation and streamflow data related to El Niño-Southern Oscillation, we use empirical mode decomposition techniques to detrend the time series. The long-term increasing trend in rainfall is remarkably different from the observed changes in streamflow that exhibit a decreasing trend. Hence, observed changes in streamflow are not the result of long-term climate change but very likely result from direct anthropogenic disturbances after land cover change. Partial water budgets for montane cloud forest and páramo ecosystems suggest that the strongest changes in evaporative water losses are observed in páramo ecosystems, where progressive colonization and afforestation of high alpine grasslands leads to a strong increase in transpiration losses.

  16. Long term prospective of the Seine River system: Confronting climatic and direct anthropogenic changes

    International Nuclear Information System (INIS)

    Ducharne, A.; Baubion, C.; Beaudoin, N.; Benoit, M.; Billen, G.; Brisson, N.; Garnier, J.; Kieken, H.; Lebonvallet, S.; Ledoux, E.; Mary, B.; Mignolet, C.; Poux, X.; Sauboua, E.; Schott, C.; Thery, S.; Viennot, P.

    2007-01-01

    To explore the evolution of a human impacted river, the Seine (France), over the 21st century, three driving factors were examined: climate, agriculture, and point source inputs of domestic and industrial origin. Three future scenarios were constructed, by modification of a baseline representative of recent conditions. A climate change scenario, based on simulations by a general circulation model driven by the SRES-A2 scenario of radiative forcing, accounts for an average warming of + 3.3 deg. C over the watershed and marked winter increase and summer decrease in precipitation. To illustrate a possible reduction in nitrate pollution from agricultural origin, a scenario of good agricultural practices was considered, introducing catch crops and a 20% decrease in nitrogen fertilisation. Future point source pollution was estimated following the assumptions embedded in scenario SRES-A2 regarding demographic, economic and technologic changes, leading to reductions of 30 to 75% compared to 2000, depending on the pollutants. Four models, addressing separate components of the river system (agronomical model, hydrogeological model, land surface model and water quality model), were used to analyse the relative impact of these scenarios on water quality, in light of their impact on hydrology and crop production. The first-order driving factor of water quality over the 21st century is the projected reduction of point source pollution, inducing a noticeable decrease in eutrophication and oxygen deficits downstream from Paris. The impact of climate change on these terms is driven by the warming of the water column. It enhances algal growth in spring and the loss factors responsible for phytoplankton mortality in late summer (grazers and viruses). In contrast, increased seasonal contrasts in river discharge have a negligible impact on river water quality, as do the changes in riverine nitrate concentration, which never gets limiting. The latter changes have a similar magnitude

  17. Experimental Forests and climate change: views of long-term employees on ecological change and the role of Experimental Forests and Ranges in understanding and adapting to climate change

    Science.gov (United States)

    Laurie Yung; Mason Bradbury; Daniel R. Williams

    2012-01-01

    In this project, we examined the views of 21 long-term employees on climate change in 14 Rocky Mountain Research Station Experimental Forests and Ranges (EFRs). EFRs were described by employees as uniquely positioned to advance knowledge of climate change impacts and adaptation strategies due to the research integrity they provide for long-term studies, the ability to...

  18. Ca isotopes reveal weak control of tectonic uplift on long-term climate change

    Science.gov (United States)

    Moore, J.; Jacobson, A. D.; Holmden, C. E.; Craw, D.

    2010-12-01

    , which are longer on the eastern side of the main divide. After correcting for this input, we apportion Ca in all rivers to silicate versus carbonate weathering using a two-component mixing equation. For non-glaciated streams, the δ44/40Ca method and a conventional Ca/Na method agree within 2%. Silicate weathering contributes less Ca west of the main divide where uplift rates are highest. For actively glaciated catchments, the δ44/40Ca method attributes 26% more Ca to silicate weathering than the Ca/Na method. We ascribe this difference to non-stoichiometric leaching of Ca from freshly cleaved rock surfaces. This reaction must occur even faster than carbonate weathering, which dominates in adjacent non-glaciated watersheds. Our results support the assertion that mountain uplift does not dramatically elevate long-term atmospheric CO2 consumption rates compared to tectonically stable landscapes. However, δ44/40Ca reveals that glaciation, which is genetically linked to mountain uplift, yields moderately higher CO2 consumption rates than previously realized. Additionally, our study highlights how biological processes can influence the terrestrial Ca cycle.

  19. A Methodology to Infer Crop Yield Response to Climate Variability and Change Using Long-Term Observations

    Directory of Open Access Journals (Sweden)

    Manfred A. Lange

    2013-11-01

    Full Text Available A new methodology to extract crop yield response to climate variability and change from long-term crop yield observations is presented in this study. In contrast to the existing first-difference approach (FDA, the proposed methodology considers that the difference in value between crop yields of two consecutive years reflects necessarily the contributions of climate and management conditions, especially at large spatial scales where both conditions may vary significantly from one year to the next. Our approach was applied to remove the effect of non-climatic factors on crop yield and, hence, to isolate the effect of the observed climate change between 1961 and 2006 on three widely crops grown in three Mediterranean countries—namely wheat, corn and potato—using national-level crop yield observations’ time-series. Obtained results show that the proposed methodology provides us with a ground basis to improve substantially our understanding of crop yield response to climate change at a scale that is relevant to large-scale estimations of agricultural production and to food security analyses; and therefore to reduce uncertainties in estimations of potential climate change effects on agricultural production. Furthermore, a comparison of outputs of our methodology and FDA outputs yielded a difference in terms of maize production in Egypt, for example, that exceeds the production of some neighbouring countries.

  20. Long-term effects of a climate change teaching campaign – a case study

    DEFF Research Database (Denmark)

    Cruys-Bagger, Søren Ib; Daugbjerg, Peer

    The authors perform in association with School of Education, Aarhus University an evaluation of the long term effects of the campaign visit. We are investigating the sustainable effect of science campaigns for schools by collecting teachers reflection on the value of the visit of “Klimakaravanen”...... of doing experiments c) Relations to technological companies and the civil society d) Skills of planning, performing and evaluating teaching...

  1. Ikh Turgen Mountain Glacier Change and 3d Surface Extents Prediction Using Long Term Landsat Image and Climate Data

    Science.gov (United States)

    Nasanbat, Elbegjargal; Erdenebat, Erdenetogtokh; Chogsom, Bolorchuluun; Lkhamjav, Ochirkhuyag; Nanzad, Lkhagvadorj

    2018-04-01

    The glacier is most important the freshwater resources and indicator of the climate change. The researchers noted that during last decades the glacier is melting due to global warming. The study calculates a spatial distribution of protentional change of glacier coverage in the Ikh Turgen mountain of Western Mongolia, and it integrates long-term climate data and satellite datasets. Therefore, in this experiment has tried to estimation three-dimensional surface area of the glacier. For this purpose, Normalized difference snow index (NDSI) was applied to decision tree approach, using Landsat MSS, TM, ETM+ and LC8 imagery for 1975-2016, a surface and slope for digital elevation model, precipitation and air temperature historical data of meteorological station. The potential volume area significantly changed glacier cover of the Ikh Turgen Mountain, and the area affected by highly variable precipitation and air temperature regimes. Between 1972 and 2016, a potential area of glacier area has been decreased in Ikh Turgen mountain region.

  2. Long term effects on potential repository sites: climatic and geomorphological changes

    International Nuclear Information System (INIS)

    Seddon, M.B.; Worsley, P.

    1985-05-01

    A study of the effects of climatic variability on the geomorphological processes operating on the landscape are important in the study of radioactive waste repository sites. The effects of glacial erosion and deposition are fundamental to an examination of repository safety, particularly in North Britain. Rates of climatic shift need to be examined. Predictive simulation models, based on a knowledge of past climatic events, for future global climates are proposed. (UK)

  3. Long-term changes in lower tropospheric baseline ozone concentrations: Comparing chemistry-climate models and observations at northern midlatitudes

    Science.gov (United States)

    Parrish, D. D.; Lamarque, J.-F.; Naik, V.; Horowitz, L.; Shindell, D. T.; Staehelin, J.; Derwent, R.; Cooper, O. R.; Tanimoto, H.; Volz-Thomas, A.; Gilge, S.; Scheel, H.-E.; Steinbacher, M.; Fröhlich, M.

    2014-05-01

    Two recent papers have quantified long-term ozone (O3) changes observed at northern midlatitude sites that are believed to represent baseline (here understood as representative of continental to hemispheric scales) conditions. Three chemistry-climate models (NCAR CAM-chem, GFDL-CM3, and GISS-E2-R) have calculated retrospective tropospheric O3 concentrations as part of the Atmospheric Chemistry and Climate Model Intercomparison Project and Coupled Model Intercomparison Project Phase 5 model intercomparisons. We present an approach for quantitative comparisons of model results with measurements for seasonally averaged O3 concentrations. There is considerable qualitative agreement between the measurements and the models, but there are also substantial and consistent quantitative disagreements. Most notably, models (1) overestimate absolute O3 mixing ratios, on average by 5 to 17 ppbv in the year 2000, (2) capture only 50% of O3 changes observed over the past five to six decades, and little of observed seasonal differences, and (3) capture 25 to 45% of the rate of change of the long-term changes. These disagreements are significant enough to indicate that only limited confidence can be placed on estimates of present-day radiative forcing of tropospheric O3 derived from modeled historic concentration changes and on predicted future O3 concentrations. Evidently our understanding of tropospheric O3, or the incorporation of chemistry and transport processes into current chemical climate models, is incomplete. Modeled O3 trends approximately parallel estimated trends in anthropogenic emissions of NOx, an important O3 precursor, while measured O3 changes increase more rapidly than these emission estimates.

  4. Long-term climate change: the evolution of shield surface boundary conditions

    International Nuclear Information System (INIS)

    Peltier, W.R.

    2007-01-01

    The Earths surface during the Pleistocene epoch has been repeatedly subjected to glacial cycles that have markedly influenced both the landscape and surface boundary conditions that, in part, governed past evolution of deep-seated Shield groundwater flow domains. As part of the Deep Geologic Repository Technology Programme simulations of the last Laurentide glacial episode have been undertaken with the University of Toronto Glacial System Model (GSM). The purpose of these simulations is to yield constrained predictions of the magnitude and time rate of change of peri-glacial, glacial and boreal regimes that have perturbed Shield flow domains in the geologic past. A detailed model of long timescale climate change has been developed, which is able to make useful predictions of the process of continental glaciation and deglaciation that has occurred in the past due to the small changes in the effective intensity of the Sun at the location of the Earth caused by gravitational many body effects in Solar System evolution. Based upon the success of this model we are able to assert that we have demonstrated a basic understanding of why this process has continually recurred in the past on a timescale of approximately 100 000 years. Continuing work with the Glacial Systems Model and efforts to provide explicit linkage to numerical analyses of sub-surface hydrology are beginning to yield a new understanding of groundwater flow system evolution and response to glacial perturbations. In so doing this understanding is not only providing a reasoned basis on which to examine issues of geosphere stability as relevant to the safety of a hypothetical repository for used nuclear fuel in Shield terrain, but is also offering an improved basis for the integrated interpretation of multi-disciplinary geo-scientific data necessary for development of a descriptive geosphere model that is seen as fundamental to the repository Safety Case. (author)

  5. Long-term multifactorial climate change impacts on mesofaunal biomass and nitrogen content

    DEFF Research Database (Denmark)

    Madsen, Mette Vestergård; Dyrnum, Kristine; Michelsen, Anders

    2015-01-01

    increased at elevated CO2, or tended do so. In contrast, enchytraeid N content decreased at elevated CO2. Soil microbial biomass N pool and litter C:N ratio also increased with elevated CO2, which suggests that mite biomasses are more coupled to microbial biomass, whereas enchytraeid biomass to a larger...... extent is governed by litter nitrogen concentration, i.e. litter quality. Structural equation modelling confirmed the positive coupling between soil microbial N content and oribatid biomass and further between oribatid and mesostigmatic biomass. The SEM also revealed a negative relationship between...... microbial N content and enchytraeid biomass. The biomass of all mesofaunal groups was reduced by spring drought, especially when combined with warming. Enchytraeid and especially collembolan biomass suffered greater drought declines than mite biomasses. We conclude that under long-term elevated CO2 exposure...

  6. Tree ring imprints of long-term changes in climate in western ...

    Indian Academy of Sciences (India)

    Prakash

    2009-10-26

    Oct 26, 2009 ... tree-ring sampling sites poses difficulty in calibrating tree-ring data against climate data especially precipitation for its strong spatial .... drained soils are its primary ecological requirement. The .... rapid radiation loss at night.

  7. Changing forest water yields in response to climate warming: results from long-term experimental watershed sites across North America

    Science.gov (United States)

    Irena F. Creed; Adam T. Spargo; Julia A. Jones; Jim M. Buttle; Mary B. Adams; Fred D. Beall; Eric G. Booth; John L. Campbell; Dave Clow; Kelly Elder; Mark B. Green; Nancy B. Grimm; Chelcy Miniat; Patricia Ramlal; Amartya Saha; Stephen Sebestyen; Dave Spittlehouse; Shannon Sterling; Mark W. Williams; Rita Winkler; Huaxia. Yao

    2014-01-01

    Climate warming is projected to affect forest water yields but the effects are expected to vary.We investigated how forest type and age affect water yield resilience to climate warming. To answer this question, we examined the variability in historical water yields at long-term experimental catchments across Canada and the United States over 5-year cool and warm...

  8. Long Term Quantification of Climate and Land Cover Change Impacts on Streamflow in an Alpine River Catchment, Northwestern China

    Directory of Open Access Journals (Sweden)

    Zhenliang Yin

    2017-07-01

    Full Text Available Quantifying the long term impacts of climate and land cover change on streamflow is of great important for sustainable water resources management in inland river basins. The Soil and Water Assessment Tool (SWAT model was employed to simulate the streamflow in the upper reaches of Heihe River Basin, northwestern China, over the last half century. The Sequential Uncertainty Fitting algorithm (SUFI-2 was selected to calibrate and validate the SWAT model. The results showed that both Nash-Sutcliffe efficiency (NSE and determination coefficient (R2 were over 0.93 for calibration and validation periods, the percent bias (PBIAS of the two periods were—3.47% and 1.81%, respectively. The precipitation, average, maximum, and minimum air temperature were all showing increasing trends, with 14.87 mm/10 years, 0.30 °C/10 years, 0.27 °C/10 year, and 0.37 °C/10 years, respectively. Runoff coefficient has increased from 0.36 (averaged during 1964 to 1988 to 0.39 (averaged during 1989 to 2013. Based on the SWAT simulation, we quantified the contribution of climate and land cover change to streamflow change, indicated that the land cover change had a positive impact on river discharge by increasing 7.12% of the streamflow during 1964 to 1988, and climate change contributed 14.08% for the streamflow increasing over last 50 years. Meanwhile, the climate change impact was intensive after 2000s. The increasing of streamflow contributed to the increasing of total streamflow by 64.1% for cold season (November to following March and 35.9% for warm season (April to October. The results provide some references for dealing with climate and land cover change in an inland river basin for water resource management and planning.

  9. Long-term dynamics emerging in floodplains and deltas from the interactions between hydrology and society in a changing climate

    Science.gov (United States)

    Di Baldassarre, Giuliano; Viglione, Alberto; Yan, Kun; Brandimarte, Luigia; Blöschl, Günter

    2014-05-01

    Economic losses and fatalities associated to flood events have increased dramatically over the past decades. This situation might worsen in the near future because of rapid urbanization of many floodplains and deltas, along with enhancement of flood water levels as a result of human interventions, climate variability or sea level rise. To explore future dynamics, we developed a novel approach, which takes into account the dynamic nature of flood risk by an explicit treatment of the interactions and feedbacks between the hydrological and social components of flood risk (i.e. probability of flooding, and potential adverse consequences). In particular, we developed a socio-hydrological model that allows considering how the frequency and magnitude of flooding shapes the evolution of societies, while, at the same time, dynamic societies shape the frequency and magnitude of flooding. We then use this model to simulate long-term dynamics of different types of societies under hydrological change, e.g. increasing flood frequency. Based on the study of long-term dynamics of different floodplains and deltas around the world (e.g. Netherlands, Bangladesh), we identify two main typologies of flood-shaped societies: i) techno-societies, which "fight floods", and typically deal with risk by building and strengthening flood protection structures, such as levees or dikes; and ii) green-societies, which "lives with floods", and mainly cope with risk via adaptation measures, such as resettling out of flood prone areas. The outcomes of this study are relevant for the management of deltas and floodplains as they allow a comparison of long-term dynamics between diverse types of societies in terms of robustness to hydrological change.

  10. Long-term monitoring of an amphibian community after a climate change- and infectious disease-driven species extirpation.

    Science.gov (United States)

    Bosch, Jaime; Fernández-Beaskoetxea, Saioa; Garner, Trenton W J; Carrascal, Luis María

    2018-02-15

    Infectious disease and climate change are considered major threats to biodiversity and act as drivers behind the global amphibian decline. This is, to a large extent, based on short-term studies that are designed to detect the immediate and strongest biodiversity responses to a threatening process. What few long-term studies are available, although typically focused on single species, report outcomes that often diverge significantly from the short-term species responses. Here, we report the results of an 18-year survey of an amphibian community exposed to both climate warming and the emergence of lethal chytridiomycosis. Our study shows that the impacts of infectious disease are ongoing but restricted to two out of nine species that form the community, despite the fact all species can become infected with the fungus. Climate warming appears to be affecting four out of the nine species, but the response of three of these is an increase in abundance. Our study supports a decreasing role of infectious disease on the community, and an increasing and currently positive effect of climate warming. We caution that if the warming trends continue, the net positive effect will turn negative as amphibian breeding habitat becomes unavailable as water bodies dry, a pattern that already may be underway. © 2018 John Wiley & Sons Ltd.

  11. Impact assessment of climate change on tourism in the Pacific small islands based on the database of long-term high-resolution climate ensemble experiments

    Science.gov (United States)

    Watanabe, S.; Utsumi, N.; Take, M.; Iida, A.

    2016-12-01

    This study aims to develop a new approach to assess the impact of climate change on the small oceanic islands in the Pacific. In the new approach, the change of the probabilities of various situations was projected with considering the spread of projection derived from ensemble simulations, instead of projecting the most probable situation. The database for Policy Decision making for Future climate change (d4PDF) is a database of long-term high-resolution climate ensemble experiments, which has the results of 100 ensemble simulations. We utilized the database for Policy Decision making for Future climate change (d4PDF), which was (a long-term and high-resolution database) composed of results of 100 ensemble experiments. A new methodology, Multi Threshold Ensemble Assessment (MTEA), was developed using the d4PDF in order to assess the impact of climate change. We focused on the impact of climate change on tourism because it has played an important role in the economy of the Pacific Islands. The Yaeyama Region, one of the tourist destinations in Okinawa, Japan, was selected as the case study site. Two kinds of impact were assessed: change in probability of extreme climate phenomena and tourist satisfaction associated with weather. The database of long-term high-resolution climate ensemble experiments and the questionnaire survey conducted by a local government were used for the assessment. The result indicated that the strength of extreme events would be increased, whereas the probability of occurrence would be decreased. This change should result in increase of the number of clear days and it could contribute to improve the tourist satisfaction.

  12. Spatial and temporal distribution of long term public policy costs under uncertainty, the case of climate change

    International Nuclear Information System (INIS)

    Lecocq, F.

    2000-07-01

    Because of the inertia of the climate system, policy makers cannot avoid making early decisions regarding climate change in a sea of uncertainties. In this context, the very legitimacy of economic analysis to tackle such questions, and in particular the underlying equity issues (who pays for climate mitigation? when?) faces widespread skepticism. This thesis aims at demonstrating how public economy still remains a powerful tool to try and put some rationale into the debate, by checking the internal consistency of the different discourses, and by providing robust insights, if not definitive answers, into climate decisions. We use a set of compact integrated climate policy optimization models to progressively introduce, articulate, and assess numerically the prominent issues at stake. We obtain three main results. We first demonstrate that the so-called timing debate between short term and long term action cannot be reduced to a mere dispute over discount rate. Given the high uncertainties surrounding climate change indeed, the margins of freedom we pass on to future generations, and in particular the technical and institutional systems we transmit, become more important than the discount rate value. Secondly, we apply the various emission quota allocation rules proposed in the literature for the enlargement of annex B to developing economies. We show that the distributive outcome of these rules depends critically on ex ante assumptions about future economic and emission growth. Therefrom, we conclude that a careful design of the institutions surrounding the tradable permits market is a necessary condition to enhance the systems robustness. Last, on a broader perspective, this thesis illustrates the complementarity between ethics and economics: though the economist does not have per se a superior word about what is fair, his toolbox is powerful enough to show how some intuitively appealing ideas, such as a zero discount rate to take care of both present and future

  13. Nuclear power: renaissance or relapse? Global climate change and long-term Three Mile Island activists' narratives.

    Science.gov (United States)

    Culley, Marci R; Angelique, Holly

    2010-06-01

    Community narratives are increasingly important as people move towards an ecologically sustainable society. Global climate change is a multi-faceted problem with multiple stakeholders. The voices of affected communities must be heard as we make decisions of global significance. We document the narratives of long-term anti-nuclear activists near the Three Mile Island (TMI) nuclear power plant who speak out in the dawn of a nuclear renaissance/relapse. While nuclear power is marketed as a "green" solution to global warming, their narratives reveal three areas for consideration; (1) significant problems with nuclear technology, (2) lessons "not" learned from the TMI disaster, and (3) hopes for a sustainable future. Nuclear waste, untrustworthy officials and economic issues were among the problems cited. Deceptive shaping of public opinion, nuclear illiteracy, and an aging anti-nuclear movement were reasons cited for the lessons not learned. However, many remain optimistic and envision increased participation to create an ecologically-balanced world.

  14. Long-term data from a small mammal community reveal loss of diversity and potential effects of local climate change.

    Science.gov (United States)

    Santoro, Simone; Sanchez-Suarez, Cristina; Rouco, Carlos; Palomo, L Javier; Fernández, M Carmen; Kufner, Maura B; Moreno, Sacramento

    2017-10-01

    Climate change affects distribution and persistence of species. However, forecasting species' responses to these changes requires long-term data series that are often lacking in ecological studies. We used 15 years of small mammal trapping data collected between 1978 and 2015 in 3 areas at Doñana National Park (southwest Spain) to (i) describe changes in species composition and (ii) test the association between local climate conditions and size of small mammal populations. Overall, 5 species were captured: wood mouse Apodemus sylvaticus , algerian mouse Mus spretus , greater white-toothed shrew Crocidura russula , garden dormouse Eliomys quercinus , and black rat Rattus rattus . The temporal pattern in the proportion of captures of each species suggests that the small mammal diversity declined with time. Although the larger species (e.g., E. quercinus ), better adapted to colder climate, have disappeared from our trapping records, M. spretus , a small species inhabiting southwest Europe and the Mediterranean coast of Africa, currently is almost the only trapped species. We used 2-level hierarchical models to separate changes in abundance from changes in probability of capture using records of A. sylvaticus in all 3 areas and of M. spretus in 1. We found that heavy rainfall and low temperatures were positively related to abundance of A. sylvaticus , and that the number of extremely hot days was negatively related to abundance of M. spretus . Despite other mechanisms are likely to be involved, our findings support the importance of climate for the distribution and persistence of these species and raise conservation concerns about potential cascading effects in the Doñana ecosystem.

  15. Changing forest water yields in response to climate warming: results from long-term experimental watershed sites across North America

    Science.gov (United States)

    Creed, Irena F; Spargo, Adam T; Jones, Julia A; Buttle, Jim M; Adams, Mary B; Beall, Fred D; Booth, Eric G; Campbell, John L; Clow, Dave; Elder, Kelly; Green, Mark B; Grimm, Nancy B; Miniat, Chelcy; Ramlal, Patricia; Saha, Amartya; Sebestyen, Stephen; Spittlehouse, Dave; Sterling, Shannon; Williams, Mark W; Winkler, Rita; Yao, Huaxia

    2014-01-01

    Climate warming is projected to affect forest water yields but the effects are expected to vary. We investigated how forest type and age affect water yield resilience to climate warming. To answer this question, we examined the variability in historical water yields at long-term experimental catchments across Canada and the United States over 5-year cool and warm periods. Using the theoretical framework of the Budyko curve, we calculated the effects of climate warming on the annual partitioning of precipitation (P) into evapotranspiration (ET) and water yield. Deviation (d) was defined as a catchment's change in actual ET divided by P [AET/P; evaporative index (EI)] coincident with a shift from a cool to a warm period – a positive d indicates an upward shift in EI and smaller than expected water yields, and a negative d indicates a downward shift in EI and larger than expected water yields. Elasticity was defined as the ratio of interannual variation in potential ET divided by P (PET/P; dryness index) to interannual variation in the EI – high elasticity indicates low d despite large range in drying index (i.e., resilient water yields), low elasticity indicates high d despite small range in drying index (i.e., nonresilient water yields). Although the data needed to fully evaluate ecosystems based on these metrics are limited, we were able to identify some characteristics of response among forest types. Alpine sites showed the greatest sensitivity to climate warming with any warming leading to increased water yields. Conifer forests included catchments with lowest elasticity and stable to larger water yields. Deciduous forests included catchments with intermediate elasticity and stable to smaller water yields. Mixed coniferous/deciduous forests included catchments with highest elasticity and stable water yields. Forest type appeared to influence the resilience of catchment water yields to climate warming, with conifer and deciduous catchments more susceptible to

  16. A model integrating longshore and cross-shore processes for predicting long-term shoreline response to climate change

    Science.gov (United States)

    Vitousek, Sean; Barnard, Patrick; Limber, Patrick W.; Erikson, Li; Cole, Blake

    2017-01-01

    We present a shoreline change model for coastal hazard assessment and management planning. The model, CoSMoS-COAST (Coastal One-line Assimilated Simulation Tool), is a transect-based, one-line model that predicts short-term and long-term shoreline response to climate change in the 21st century. The proposed model represents a novel, modular synthesis of process-based models of coastline evolution due to longshore and cross-shore transport by waves and sea-level rise. Additionally, the model uses an extended Kalman filter for data assimilation of historical shoreline positions to improve estimates of model parameters and thereby improve confidence in long-term predictions. We apply CoSMoS-COAST to simulate sandy shoreline evolution along 500 km of coastline in Southern California, which hosts complex mixtures of beach settings variably backed by dunes, bluffs, cliffs, estuaries, river mouths, and urban infrastructure, providing applicability of the model to virtually any coastal setting. Aided by data assimilation, the model is able to reproduce the observed signal of seasonal shoreline change for the hindcast period of 1995-2010, showing excellent agreement between modeled and observed beach states. The skill of the model during the hindcast period improves confidence in the model's predictive capability when applied to the forecast period (2010-2100) driven by GCM-projected wave and sea-level conditions. Predictions of shoreline change with limited human intervention indicate that 31% to 67% of Southern California beaches may become completely eroded by 2100 under sea-level rise scenarios of 0.93 to 2.0 m.

  17. Long term impact of climate change on the metropolitan coast; Impacts a long terme du changement climatique sur le littoral metropolitain

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2011-07-01

    In its first part, this report describes global physical phenomena: air and sea temperature rise, modification of the tempest regime, precipitations, ocean stratification. Then, it describes some more specific physical effects of climate change: average sea level rise, sea currents (global, regional and local oceanic circulation), and wave modification on the coast. It describes the effects of various media due to sea submersion, erosion and accretion, ocean acidification, salinization increase of underground coastal waters, modification of the composition of biotic communities, biological invasions, and appearance of new toxicities for mankind

  18. An assessment of long-term overtopping risk and optimal termination time of dam under climate change.

    Science.gov (United States)

    Lee, Bau-Shian; You, Gene Jiing-Yun

    2013-05-30

    Reservoir management faces a wide range of new challenges resulting from the impact of climate change. One set of challenges arises from the non-stationary nature of hydrological conditions. Another crucial issue is watershed sedimentation, which can significantly influence the sustainability and safety of reservoirs. To address these concerns, this study developed a framework for the management of reservoir risk. An analytical conceptual model coupling physical governing relationships and economic tools was proposed, which was then applied to the Shihmen Reservoir in Taiwan. We adopted a statistical representation of future hydrologic conditions with the assumption of time-variant moments and focused on evaluating the impact of an increase in the frequency of extreme hydrological events caused by climate change and used a stochastic approach to quantify the risk factors. Our results confirm that this approach can be used to identify reservoir-related risks and generate appropriate options for strategy and policy. We determined that the major source of risk is the hydrological conditions, especially the extreme events. More severe intra-annual climatic change is much more dominant in the risk compared to inter-year trends. The influence of reservoir characteristics on risk is associated mainly with the availability of flood control capacity, but limited due to the limitation of its volume and potential to regulate the flow. Engineering may provide an option for mitigating the risk, but integrated, watershed-level approaches, such as providing systematic detention or land use management, are better suited to reducing the storm peak from a long-term perspective. With a critical increase in the risk of overtopping, a high probability of dam failure and corresponding losses may precipitate the need to retire or remove the facility. However, because the benefits and costs are both huge, the decision may be biased by a conservative attitude. The outcome of small

  19. Northern European long term climate archives

    Energy Technology Data Exchange (ETDEWEB)

    Hohl, Veronica [Stockholm Univ. (Sweden)

    2005-01-01

    The Swedish Nuclear Fuel and Waste Management Company is responsible for the management and disposal of Sweden's radioactive waste. It is intended to deposit the spent nuclear fuel in a deep geological repository. This repository shall keep the radiotoxic material separated from humans and the environment for extended periods, from decades to millennia and possibly to geological timescales. During this time perspective climate induced changes such as shore-level displacement and evolution of permafrost and ice sheets are expected to occur which may affect the repository. The possible occurrence, extent and duration of these long-term changes, are therefore of interest when considering the assessment of repository performance and safety. The main climate parameters determining both surface and subsurface conditions are temperature and precipitation. As a result of the last advance of the Weichselian ice sheet only few geological archives exist, which contain information on past climatic conditions in Sweden before c 16,000 years BP. The purpose of this literature review is to compile and evaluate available information from Scandinavian, Northern and Central European geological archives, which record climatic conditions during the Weichselian time period. The compilation provides paleotemperature data sets, which may be used to explore the possible evolution of periglacial permafrost in Sweden. This report is a synopsis of 22 publications detailing climatic and environmental changes during the Weichselian time period in Northwestern Europe based on quantified paleotemperature records. Some of the data is presented as temperature curves which were digitised specifically for this report. The time range covered by the different publications varies considerably. Only few authors dealt with the whole Weichselian period and the majority cover only a few thousand years. This however is not considered to influence the reliability of the archives. The reason for the

  20. Northern European long term climate archives

    International Nuclear Information System (INIS)

    Hohl, Veronica

    2005-01-01

    The Swedish Nuclear Fuel and Waste Management Company is responsible for the management and disposal of Sweden's radioactive waste. It is intended to deposit the spent nuclear fuel in a deep geological repository. This repository shall keep the radiotoxic material separated from humans and the environment for extended periods, from decades to millennia and possibly to geological timescales. During this time perspective climate induced changes such as shore-level displacement and evolution of permafrost and ice sheets are expected to occur which may affect the repository. The possible occurrence, extent and duration of these long-term changes, are therefore of interest when considering the assessment of repository performance and safety. The main climate parameters determining both surface and subsurface conditions are temperature and precipitation. As a result of the last advance of the Weichselian ice sheet only few geological archives exist, which contain information on past climatic conditions in Sweden before c 16,000 years BP. The purpose of this literature review is to compile and evaluate available information from Scandinavian, Northern and Central European geological archives, which record climatic conditions during the Weichselian time period. The compilation provides paleotemperature data sets, which may be used to explore the possible evolution of periglacial permafrost in Sweden. This report is a synopsis of 22 publications detailing climatic and environmental changes during the Weichselian time period in Northwestern Europe based on quantified paleotemperature records. Some of the data is presented as temperature curves which were digitised specifically for this report. The time range covered by the different publications varies considerably. Only few authors dealt with the whole Weichselian period and the majority cover only a few thousand years. This however is not considered to influence the reliability of the archives. The reason for the varying

  1. Simulating infectious disease risk based on climatic drivers: from numerical weather prediction to long term climate change scenario

    Science.gov (United States)

    Caminade, C.; Ndione, J. A.; Diallo, M.; MacLeod, D.; Faye, O.; Ba, Y.; Dia, I.; Medlock, J. M.; Leach, S.; McIntyre, K. M.; Baylis, M.; Morse, A. P.

    2012-04-01

    Climate variability is an important component in determining the incidence of a number of diseases with significant health and socioeconomic impacts. In particular, vector born diseases are the most likely to be affected by climate; directly via the development rates and survival of both the pathogen and the vector, and indirectly through changes in the surrounding environmental conditions. Disease risk models of various complexities using different streams of climate forecasts as inputs have been developed within the QWeCI EU and ENHanCE ERA-NET project frameworks. This work will present two application examples, one for Africa and one for Europe. First, we focus on Rift Valley fever over sub-Saharan Africa, a zoonosis that affects domestic animals and humans by causing an acute fever. We show that the Rift Valley fever outbreak that occurred in late 2010 in the northern Sahelian region of Mauritania might have been anticipated ten days in advance using the GFS numerical weather prediction system. Then, an ensemble of regional climate projections is employed to model the climatic suitability of the Asian tiger mosquito for the future over Europe. The Asian tiger mosquito is an invasive species originally from Asia which is able to transmit West Nile and Chikungunya Fever among others. This species has spread worldwide during the last decades, mainly through the shipments of goods from Asia. Different disease models are employed and inter-compared to achieve such a task. Results show that the climatic conditions over southern England, central Western Europe and the Balkans might become more suitable for the mosquito (including the proviso that the mosquito has already been introduced) to establish itself in the future.

  2. Age, origin and evolution of Antarctic debris-covered glaciers: Implications for landscape evolution and long-term climate change

    Science.gov (United States)

    Mackay, Sean Leland

    Antarctic debris-covered glaciers are potential archives of long-term climate change. However, the geomorphic response of these systems to climate forcing is not well understood. To address this concern, I conducted a series of field-based and numerical modeling studies in the McMurdo Dry Valleys of Antarctica (MDV), with a focus on Mullins and Friedman glaciers. I used data and results from geophysical surveys, ice-core collection and analysis, geomorphic mapping, micro-meteorological stations, and numerical-process models to (1) determine the precise origin and distribution of englacial and supraglacial debris within these buried-ice systems, (2) quantify the fundamental processes and feedbacks that govern interactions among englacial and supraglacial debris, (3) establish a process-based model to quantify the inventory of cosmogenic nuclides within englacial and supraglacial debris, and (4) isolate the governing relationships between the evolution of englacial /supraglacial debris and regional climate forcing. Results from 93 field excavations, 21 ice cores, and 24 km of ground-penetrating radar data show that Mullins and Friedman glaciers contain vast areas of clean glacier ice interspersed with inclined layers of concentrated debris. The similarity in the pattern of englacial debris bands across both glaciers, along with model results that call for negligible basal entrainment, is best explained by episodic environmental change at valley headwalls. To constrain better the timing of debris-band formation, I developed a modeling framework that tracks the accumulation of cosmogenic 3He in englacial and supraglacial debris. Results imply that ice within Mullins Glacier increases in age non-linearly from 12 ka to ˜220 ka in areas of active flow (up to >> 1.6 Ma in areas of slow-moving-to-stagnant ice) and that englacial debris bands originate with a periodicity of ˜41 ka. Modeling studies suggest that debris bands originate in synchronicity with changes in

  3. Climate change and coral reef bleaching: An ecological assessment of long-term impacts, recovery trends and future outlook

    Science.gov (United States)

    Baker, Andrew C.; Glynn, Peter W.; Riegl, Bernhard

    2008-12-01

    Since the early 1980s, episodes of coral reef bleaching and mortality, due primarily to climate-induced ocean warming, have occurred almost annually in one or more of the world's tropical or subtropical seas. Bleaching is episodic, with the most severe events typically accompanying coupled ocean-atmosphere phenomena, such as the El Niño-Southern Oscillation (ENSO), which result in sustained regional elevations of ocean temperature. Using this extended dataset (25+ years), we review the short- and long-term ecological impacts of coral bleaching on reef ecosystems, and quantitatively synthesize recovery data worldwide. Bleaching episodes have resulted in catastrophic loss of coral cover in some locations, and have changed coral community structure in many others, with a potentially critical influence on the maintenance of biodiversity in the marine tropics. Bleaching has also set the stage for other declines in reef health, such as increases in coral diseases, the breakdown of reef framework by bioeroders, and the loss of critical habitat for associated reef fishes and other biota. Secondary ecological effects, such as the concentration of predators on remnant surviving coral populations, have also accelerated the pace of decline in some areas. Although bleaching severity and recovery have been variable across all spatial scales, some reefs have experienced relatively rapid recovery from severe bleaching impacts. There has been a significant overall recovery of coral cover in the Indian Ocean, where many reefs were devastated by a single large bleaching event in 1998. In contrast, coral cover on western Atlantic reefs has generally continued to decline in response to multiple smaller bleaching events and a diverse set of chronic secondary stressors. No clear trends are apparent in the eastern Pacific, the central-southern-western Pacific or the Arabian Gulf, where some reefs are recovering and others are not. The majority of survivors and new recruits on

  4. Long-term patterns in fish phenology in the western Dutch Wadden Sea in relation to climate change

    Science.gov (United States)

    van Walraven, Lodewijk; Dapper, Rob; Nauw, Janine J.; Tulp, Ingrid; Witte, Johannes IJ.; van der Veer, Henk W.

    2017-09-01

    Long-term patterns in fish phenology in the western Dutch Wadden Sea were studied using a 53 year (1960-2013) high resolution time series of daily kom-fyke catches in spring and autumn. Trends in first appearance, last occurrence and peak abundance were analysed for the most common species in relation to mode of life (pelagic, demersal, benthopelagic) and biogeographic guild (northern or southern distribution). Climate change in the western Wadden Sea involved an increase in water temperature from 1980 onwards. The main pattern in first day of occurrence, peak occurrence and last day of occurrence was similar: a positive trend over time and a correlation with spring and summer water temperature. This is counterintuitive; with increasing temperature, an advanced immigration of fish species would be expected. An explanation might be that water temperatures have increased offshore as well and hence fish remain longer there, delaying their immigration to the Wadden Sea. The main trend towards later date of peak occurrence and last day of occurrence was in line with our expectations: a forward shift in immigration into the Wadden Sea implies also that peak abundance is delayed. As a consequence of the increased water temperature, autumn water temperature remains favourable longer than before. For most of the species present, the Wadden Sea is not near the edge of their distributional range. The most striking phenological shifts occurred in those individual species for which the Wadden Sea is near the southern or northern edge of their distribution.

  5. Long-Term Climate Change Assessment Task for the Hanford Site Permanent Isolation Barrier Development Program: Status through FY 1992

    Energy Technology Data Exchange (ETDEWEB)

    Petersen, K.L. [Westinghouse Hanford Co., Richland, WA (US); Chatters, J.C. [Pacific Northwest Lab., Richland, WA (US)

    1993-07-01

    The Hanford Site Permanent Isolation Barrier Development Program (Barrier Development Program) was organized (Adams and Wing 1986) to develop the technology needed to provide an in-place disposal capability for the US Department of Energy at the Hanford Site in southeastern Washington. The goals of the Barrier Development Program are to provide defensible evidence that final barrier design(s) will adequately control water infiltration, plant and animal intrusion, and wind and water erosion for a minimum of 1,000 years; to isolate wastes from the accessible environment; and to use markers to warn inadvertent human intruders. Evidence for barrier performance will be obtained by conducting laboratory experiments, field tests, computer modeling, and other studies that establish confidence in the barrier`s ability to meet its 1,000-year design life. The performance and stability of natural barrier analogs that have existed for several millennia and the reconstruction of climate changes during the past 10,000 to 125,000 years also will provide insight into bounding conditions of possible future changes and increase confidence in the barriers design. In the following discussion the term {open_quotes}long-term{close_quotes} references periods of time up to 1000`s of years, distinguishing it from {open_quotes}short-term{close_quotes} weather patterns covering a decade or less. Specific activities focus on planning and conducting a series of studies and tests required to confirm key aspects of the barrier design. The effort is a collaborative one between scientists and engineers from Westinghouse Hanford Company (Westinghouse Hanford) and Pacific Northwest Laboratory (PNL) to design barriers to limit movement of radionuclides and other contaminants to the accessible environment for at least 1,000 years. These activities have been divided into 14 groups of tasks that aid in the complete development of protective barrier and warning marker system.

  6. Using long-term ecosystem service and biodiversity data to study the impacts and adaptation options in response to climate change: insights from the global ILTER sites network

    Czech Academy of Sciences Publication Activity Database

    Vihervaara, P.; D'Amato, D.; Forsius, M.; Angelstam, P.; Baessler, C.; Balvanera, P.; Boldgiv, B.; Bourgeron, P.; Dick, J.; Kanka, R.; Klotz, S.; Maass, M.; Melecis, V.; Petřík, Petr; Shibata, H.; Tang, J.; Thompson, J.; Zacharias, S.

    2013-01-01

    Roč. 5, č. 1 (2013), s. 53-66 ISSN 1877-3435 R&D Projects: GA MŠk 7AMB12SK156 Institutional support: RVO:67985939 Keywords : climate change * long-term ecological monitoring * prmanen research plot Subject RIV: EF - Botanics Impact factor: 2.758, year: 2013

  7. Analysis of long-term changes in extreme climatic indices: a case study of the Mediterranean climate, Marmara Region, Turkey

    Science.gov (United States)

    Abbasnia, Mohsen; Toros, Hüseyin

    2018-05-01

    This study aimed to analyze extreme temperature and precipitation indices at seven stations in the Marmara Region of Turkey for the period 1961-2016. The trend of temperature indices showed that the warm-spell duration and the numbers of summer days, tropical nights, warm nights, and warm days have increased, while the cold-spell duration and number of ice days, cool nights, and cool days have decreased across the Marmara Region. Additionally, the diurnal temperature range has slightly increased at most of the stations. A majority of stations have shown significant warming trends for warm days and warm nights throughout the study area, whereas warm extremes and night-time based temperature indices have shown stronger trends compared to cold extremes and day-time indices. The analysis of precipitation indices has mostly shown increasing trends in consecutive dry days and increasing trends in annual rainfall, rainfall intensity for inland and urban stations, especially for stations in Sariyer and Edirne, which are affected by a fast rate of urbanization. Overall, a large proportion of study stations have experienced an increase in annual precipitation and heavy precipitation events, although there was a low percentage of results that was significant. Therefore, it is expected that the rainfall events will tend to become shorter and more intense, the occurrence of temperature extremes will become more pronounced in favor of hotter events, and there will be an increase in the atmospheric moisture content over the Marmara Region. This provides regional evidence for the importance of ongoing research on climate change.

  8. Estimates of the long-term U.S. economic impacts of global climate change-induced drought.

    Energy Technology Data Exchange (ETDEWEB)

    Ehlen, Mark Andrew; Loose, Verne W.; Warren, Drake E.; Vargas, Vanessa N.

    2010-01-01

    While climate-change models have done a reasonable job of forecasting changes in global climate conditions over the past decades, recent data indicate that actual climate change may be much more severe. To better understand some of the potential economic impacts of these severe climate changes, Sandia economists estimated the impacts to the U.S. economy of climate change-induced impacts to U.S. precipitation over the 2010 to 2050 time period. The economists developed an impact methodology that converts changes in precipitation and water availability to changes in economic activity, and conducted simulations of economic impacts using a large-scale macroeconomic model of the U.S. economy.

  9. Long-term climate change effects on dynamics of microorganisms and carbon in the root-zone

    DEFF Research Database (Denmark)

    Reinsch, Sabine

    Climate change factors such as elevated CO2 concentration, warming and changes in precipitation patterns have been shown to affect terrestrial carbon (C) cycling. The objective of this Ph.D. project is to track recently assimilated C into belowground compartments to investigate the effects...... of climate change on belowground C allocation. The impacts of climate change as single and combined treatments were applied to heath/grassland vegetation and the short-term terrestrial C turnover was investigated using in-situ 13CO2 pulse-labeling. We developed a mobile and low-cost pulse-labeling setup...... have major impacts on the C balance under changing climatic conditions. A comparison of C allocation under ambient and simulated future climatic conditions showed that the terrestrial C balance might be changed by reducing soil organic matter mineralization. Our results suggest that the impact...

  10. Assessing climate change effects on long-term forest development: adjusting growth, phenology, and seed production in a gap model

    NARCIS (Netherlands)

    Meer, van der P.J.; Jorritsma, I.T.M.; Kramer, K.

    2002-01-01

    The sensitivity of forest development to climate change is assessed using a gap model. Process descriptions in the gap model of growth, phenology, and seed production were adjusted for climate change effects using a detailed process-based growth modeland a regression analysis. Simulation runs over

  11. Effects of land cover and regional climate variations on long-term spatiotemporal changes in sagebrush ecosystems

    Science.gov (United States)

    Xian, George Z.; Homer, Collin G.; Aldridge, Cameron L.

    2012-01-01

    This research investigated the effects of climate and land cover change on variation in sagebrush ecosystems. We combined information of multi-year sagebrush distribution derived from multitemporal remote sensing imagery and climate data to study the variation patterns of sagebrush ecosystems under different potential disturbances. We found that less than 40% of sagebrush ecosystem changes involved abrupt changes directly caused by landscape transformations and over 60% of the variations involved gradual changes directly related to climatic perturbations. The primary increases in bare ground and declines in sagebrush vegetation abundance were significantly correlated with the 1996-2006 decreasing trend in annual precipitation.

  12. Long-term genetic monitoring of a riverine dragonfly, Orthetrum coerulescens (Odonata: Libellulidae]: Direct anthropogenic impact versus climate change effects.

    Science.gov (United States)

    Herzog, Rebecca; Hadrys, Heike

    2017-01-01

    Modern conservationists call for long term genetic monitoring datasets to evaluate and understand the impact of human activities on natural ecosystems and species on a global but also local scale. However, long-term monitoring datasets are still rare but in high demand to correctly identify, evaluate and respond to environmental changes. In the presented study, a population of the riverine dragonfly, Orthetrum coerulescens (Odonata: Libellulidae), was monitored over a time period from 1989 to 2013. Study site was an artificial irrigation ditch in one of the last European stone steppes and "nature heritage", the Crau in Southern France. This artificial riverine habitat has an unusual high diversity of odonate species, prominent indicators for evaluating freshwater habitats. A clearing of the canal and destruction of the bank vegetation in 1996 was assumed to have great negative impact on the odonate larval and adult populations. Two mitochondrial markers (CO1 & ND1) and a panel of nuclear microsatellite loci were used to assess the genetic diversity. Over time they revealed a dramatic decline in diversity parameters between the years 2004 and 2007, however not between 1996 and 1997. From 2007 onwards the population shows a stabilizing trend but has not reached the amount of genetic variation found at the beginning of this survey. This decline cannot be referred to the clearing of the canal or any other direct anthropogenic impact. Instead, it is most likely that the populations' decay was due to by extreme weather conditions during the specific years. A severe drought was recorded for the summer months of these years, leading to reduced water levels in the canal causing also other water parameters to change, and therefore impacting temperature sensitive riverine habitat specialists like the O. coerulescens in a significant way. The data provide important insights into population genetic dynamics and metrics not always congruent with traditional monitoring data (e

  13. Paleoecological studies on variability in marine fish populations: A long-term perspective on the impacts of climatic change on marine ecosystems

    Science.gov (United States)

    Finney, Bruce P.; Alheit, Jürgen; Emeis, Kay-Christian; Field, David B.; Gutiérrez, Dimitri; Struck, Ulrich

    2010-02-01

    The use of historical fishing records to understand relationships between climatic change and fish abundance is limited by the relatively short duration of these records, and complications due to the strong influence of human activity in addition to climatic change. Sedimentary records containing scales, bones or geochemical proxies of variability in fish populations provide unique insights on long-term ecosystem dynamics and relationships with climatic change. Available records from Holocene sediments are summarized and synthesized. The records are from several widespread locations near or along the continental margins of the South Atlantic and Pacific oceans, including Alaska, USA (Pacific salmon), Saanich and Effingham Inlets, British Columbia, Canada (pelagic fish), Santa Barbara Basin, California, USA (Northern anchovies and Pacific sardines), Gulf of California, Mexico (Pacific sardines, Northern anchovies and Pacific hake), Peru upwelling system (sardines, anchovies and hake), and Benguela Current System, South Africa (sardines, anchovies and hake). These records demonstrate that fish population sizes are not constant, and varied significantly over a range of time scales prior to the advent of large-scale commercial fishing. In addition to the decadal-scale variability commonly observed in historical records, the long-term records reveal substantial variability over centennial and millennial time scales. Shifts in abundance are often, but not always, correlated with regional and/or global climatic changes. The long-term perspective reveals different patterns of variability in fish populations, as well as fish-climate relationships, than suggested by analysis of historical records. Many records suggest prominent changes in fish abundance at ca. 1000-1200 AD, during the Little Ice Age, and during the transition at the end of the Little Ice Age in the 19th century that may be correlative, and that were likely driven by major hemispheric or global

  14. Mapping long-term wetland response to climate

    Science.gov (United States)

    Zhou, Q.; Gallant, A.; Rover, J.

    2016-12-01

    Wetlands provide unique feeding and breeding habitat for numerous waterfowl species. The distribution of wetlands has been considerably changed due to agricultural land conversion and hydrologic modification. Climate change may further impact wetlands through altered moisture regimes. This study characterized long-term variation in wetland conditions by using dense time series from all available Landsat data from 1985 to 2014. We extracted harmonic frequencies from 30 years to two years to delineate the long-term variation in all seven Landsat bands. A cluster analysis and unsupervised classification then enabled us to map different classes of wetland response. We demonstrated the method in the Prairie Pothole Region in North Dakota.

  15. Expanding research capabilities with sea ice climate records for analysis of long-term climate change and short-term variability

    Science.gov (United States)

    Scott, D. J.; Meier, W. N.

    2008-12-01

    Recent sea ice analysis is leading to predictions of a sea ice-free summertime in the Arctic within 20 years, or even sooner. Sea ice topics, such as concentration, extent, motion, and age, are predominately studied using satellite data. At the National Snow and Ice Data Center (NSIDC), passive microwave sea ice data sets provide timely assessments of seasonal-scale variability as well as consistent long-term climate data records. Such data sets are crucial to understanding changes and assessing their impacts. Noticeable impacts of changing sea ice conditions on native cultures and wildlife in the Arctic region are now being documented. With continued deterioration in Arctic sea ice, global economic impacts will be seen as new shipping routes open. NSIDC is at the forefront of making climate data records available to address the changes in sea ice and its global impacts. By focusing on integrated data sets, NSIDC leads the way by broadening the studies of sea ice beyond the traditional cryospheric community.

  16. Assessment of extreme flood events in a changing climate for a long-term planning of socio-economic infrastructure in the Russian Arctic

    Science.gov (United States)

    Shevnina, Elena; Kourzeneva, Ekaterina; Kovalenko, Viktor; Vihma, Timo

    2017-05-01

    Climate warming has been more acute in the Arctic than at lower latitudes and this tendency is expected to continue. This generates major challenges for economic activity in the region. Among other issues is the long-term planning and development of socio-economic infrastructure (dams, bridges, roads, etc.), which require climate-based forecasts of the frequency and magnitude of detrimental flood events. To estimate the cost of the infrastructure and operational risk, a probabilistic form of long-term forecasting is preferable. In this study, a probabilistic model to simulate the parameters of the probability density function (PDF) for multi-year runoff based on a projected climatology is applied to evaluate changes in extreme floods for the territory of the Russian Arctic. The model is validated by cross-comparison of the modelled and empirical PDFs using observations from 23 sites located in northern Russia. The mean values and coefficients of variation (CVs) of the spring flood depth of runoff are evaluated under four climate scenarios, using simulations of six climate models for the period 2010-2039. Regions with substantial expected changes in the means and CVs of spring flood depth of runoff are outlined. For the sites located within such regions, it is suggested to account for the future climate change in calculating the maximal discharges of rare occurrence. An example of engineering calculations for maximal discharges with 1 % exceedance probability is provided for the Nadym River at Nadym.

  17. The long-term effects of planting and harvesting on secondary forest dynamics under climate change in northeastern China.

    Science.gov (United States)

    Yao, Jing; He, Xingyuan; He, Hongshi; Chen, Wei; Dai, Limin; Lewis, Bernard J; Yu, Lizhong

    2016-01-04

    Unlike the virgin forest in the Changbaishan Nature Reserve in northeastern China, little research on a landscape scale has been conducted on secondary forests in the region under conditions of a warming climate. This research was undertaken in the upper Hun River region where the vegetation is representative of the typical secondary forest of northeastern China. The spatially explicit forest landscape model LANDIS was utilized to simulate the responses of forest restoration dynamics to anthropogenic disturbance (planting and harvesting) and evaluate the difference of the restoration process under continuation of current climatic conditions and climate warming. The results showed that: (1) The interaction of planting and harvesting has organizational scale effects on the forest. The combination of planting and harvesting policies has significant effects on the overall forest but not on individual species. (2) The area expansion of the historically dominant species Pinus koraiensis is less under climate warming than under continuation of current climatic conditions. These suggests that we should carefully take historically dominant species as the main focus for forest restoration, especially when they are near their natural distribution boundary, because they are probably less capable of successfully adapting to climate change.

  18. Offshore CCS and ocean acidification : A global long-term probabilistic cost-benefit analysis of climate change mitigation

    NARCIS (Netherlands)

    van der Zwaan, B.C.C.; Gerlagh, Reyer

    Public fear over environmental and health impacts of CO2 storage, or over potential leakage of CO2 from geological reservoirs, is among the reasons why over the past decade CCS has not yet been deployed on a scale large enough so as to meaningfully contribute to mitigate climate change. Storage of

  19. Few long-term effects of simulated climate change on volatile organic compound emissions and leaf chemistry of three subarctic dwarf shrubs

    DEFF Research Database (Denmark)

    Rinnan, Riikka; Rinnan, Åsmund; Faubert, Patrick

    2011-01-01

    Climate change is exposing arctic ecosystems to higher temperature, increased nutrient availability and shading due to the increasing cloud cover and the expanding forests. In this work, we assessed how these factors affect the emissions of biogenic volatile organic compounds (BVOCs) from three......-selinene from S. phylicifolia. The shading treatment obtained by dome-shaped hessian tents did not cause clear long-term changes in leaf chemistry or BVOC emissions. The only observed change was a marginally significant increase in sesquiterpene emissions from B. nana. When the treatment effects on long...

  20. Analyzing the contribution of climate change to long-term variations in sediment nitrogen sources for reservoirs/lakes

    Energy Technology Data Exchange (ETDEWEB)

    Xia, Xinghui, E-mail: xiaxh@bnu.edu.cn [School of Environment, Beijing Normal University, State Key Laboratory of Water Environment Simulation/Key Laboratory of Water and Sediment Sciences of Ministry of Education, Beijing 100875 (China); Wu, Qiong; Zhu, Baotong; Zhao, Pujun [School of Environment, Beijing Normal University, State Key Laboratory of Water Environment Simulation/Key Laboratory of Water and Sediment Sciences of Ministry of Education, Beijing 100875 (China); Zhang, Shangwei [Department of Isotope Biogeochemistry, Helmholtz Centre for Environmental Research — UFZ, Permoserstraße 15, Leipzig 04318 (Germany); Yang, Lingyan [Beijing Municipal Environmental Monitoring Center, Beijing 100048 (China)

    2015-08-01

    We applied a mixing model based on stable isotopic δ{sup 13}C, δ{sup 15}N, and C:N ratios to estimate the contributions of multiple sources to sediment nitrogen. We also developed a conceptual model describing and analyzing the impacts of climate change on nitrogen enrichment. These two models were conducted in Miyun Reservoir to analyze the contribution of climate change to the variations in sediment nitrogen sources based on two {sup 210}Pb and {sup 137}Cs dated sediment cores. The results showed that during the past 50 years, average contributions of soil and fertilizer, submerged macrophytes, N{sub 2}-fixing phytoplankton, and non-N{sub 2}-fixing phytoplankton were 40.7%, 40.3%, 11.8%, and 7.2%, respectively. In addition, total nitrogen (TN) contents in sediment showed significant increasing trends from 1960 to 2010, and sediment nitrogen of both submerged macrophytes and phytoplankton sources exhibited significant increasing trends during the past 50 years. In contrast, soil and fertilizer sources showed a significant decreasing trend from 1990 to 2010. According to the changing trend of N{sub 2}-fixing phytoplankton, changes of temperature and sunshine duration accounted for at least 43% of the trend in the sediment nitrogen enrichment over the past 50 years. Regression analysis of the climatic factors on nitrogen sources showed that the contributions of precipitation, temperature, and sunshine duration to the variations in sediment nitrogen sources ranged from 18.5% to 60.3%. The study demonstrates that the mixing model provides a robust method for calculating the contribution of multiple nitrogen sources in sediment, and this study also suggests that N{sub 2}-fixing phytoplankton could be regarded as an important response factor for assessing the impacts of climate change on nitrogen enrichment. - Highlights: • A mixing model was built to analyze sediment N sources of lakes/reservoirs. • Fertilizer/soil and macrophytes showed decreasing trends during

  1. Analyzing the contribution of climate change to long-term variations in sediment nitrogen sources for reservoirs/lakes

    International Nuclear Information System (INIS)

    Xia, Xinghui; Wu, Qiong; Zhu, Baotong; Zhao, Pujun; Zhang, Shangwei; Yang, Lingyan

    2015-01-01

    We applied a mixing model based on stable isotopic δ 13 C, δ 15 N, and C:N ratios to estimate the contributions of multiple sources to sediment nitrogen. We also developed a conceptual model describing and analyzing the impacts of climate change on nitrogen enrichment. These two models were conducted in Miyun Reservoir to analyze the contribution of climate change to the variations in sediment nitrogen sources based on two 210 Pb and 137 Cs dated sediment cores. The results showed that during the past 50 years, average contributions of soil and fertilizer, submerged macrophytes, N 2 -fixing phytoplankton, and non-N 2 -fixing phytoplankton were 40.7%, 40.3%, 11.8%, and 7.2%, respectively. In addition, total nitrogen (TN) contents in sediment showed significant increasing trends from 1960 to 2010, and sediment nitrogen of both submerged macrophytes and phytoplankton sources exhibited significant increasing trends during the past 50 years. In contrast, soil and fertilizer sources showed a significant decreasing trend from 1990 to 2010. According to the changing trend of N 2 -fixing phytoplankton, changes of temperature and sunshine duration accounted for at least 43% of the trend in the sediment nitrogen enrichment over the past 50 years. Regression analysis of the climatic factors on nitrogen sources showed that the contributions of precipitation, temperature, and sunshine duration to the variations in sediment nitrogen sources ranged from 18.5% to 60.3%. The study demonstrates that the mixing model provides a robust method for calculating the contribution of multiple nitrogen sources in sediment, and this study also suggests that N 2 -fixing phytoplankton could be regarded as an important response factor for assessing the impacts of climate change on nitrogen enrichment. - Highlights: • A mixing model was built to analyze sediment N sources of lakes/reservoirs. • Fertilizer/soil and macrophytes showed decreasing trends during the past two decades.

  2. Long-term patterns in fish phenology in the western Dutch Wadden Sea in relation to climate change

    NARCIS (Netherlands)

    van Walraven, L.; Dapper, R.; Nauw, J.J.; Tulp, I.; Witte, J.IJ.; van der Veer, H.W.

    2017-01-01

    Long-term patterns in fish phenology in the western Dutch Wadden Sea were studied using a 53 year (1960–2013) high resolution time series of daily kom-fyke catches in spring and autumn. Trends in first appearance, last occurrence and peak abundance were analysed for the most common species in

  3. Long-term change of potential evapotranspiration over Southwest China and teleconnections with large-scale climate anomalies

    Science.gov (United States)

    Liu, B.; Chen, X.; Li, Y.; Chen, Z.

    2017-12-01

    bstract: Potential evapotranspiration (PET) is a sensitive factor for atmospheric and ecological systems over Southwest China which is characterized by intensive karst geomorphology and fragile environment. Based on daily meteorological data of 94 stations during 1961-2013, the spatiotemporal characteristics of PET are analyzed. The changing characteristics of local meteorological factors and large-scale climatic features are also investigated to explain the potential reasons for changing PET. Study results are as follows: (1) The high-value center of PET with a mean value of 1097 mm/a locates in the south mainly resulted from the regional climatic features of higher air temperature (TEM), sunshine duration (SSD) and lower relative humidity (RHU); and the low-value center of PET with a mean value of 831 mm/a is in the northeast primarily attributed to higher RHU and weaker SSD. (2) Annual PET decreases at -10.04 mm decade-1 before the year 2000 but increases at 50.65 mm decade-1 thereafter; and the dominant factors of PET change are SSD, RHU and wind speed (WIN), with the relative contributions of 33.29%, 25.42% and 22.16%, respectively. (3) The abrupt change of PET in 2000 is strongly dominated by large-scale climatic anomalies. The strengthened 850hPa geostrophic wind (0.51 ms-1 decade-1), weakened total cloud cover (-2.25 % decade-1) and 500hPa water vapor flux (-2.85 % decade-1) have provided advantageous dynamic, thermal and dry conditions for PET over Southwest China since the 21st century.

  4. Modulation of the erosion rate of an uplifting landscape by long-term climate change: An experimental investigation

    Science.gov (United States)

    Moussirou, Bérangé; Bonnet, Stéphane

    2018-02-01

    Whether or not climatic variations play a major role in setting the erosion rate of continental landscapes is a key factor in demonstrating the influence of climate on the tectonic evolution of mountain belts and understanding how clastic deposits preserved in sedimentary basins may record climatic variations. Here, we investigate how a change in precipitation influences the erosional dynamics of laboratory-scale landscapes that evolved under a combination of uplift and rainfall forcings. We consider here the impact of a decrease in the precipitation rate of finite duration on the erosive response of a landscape forced by a constant uplift and initially at a steady state (SS1). We performed several experiments with the same amplitude but different durations of precipitation decrease (Tp). We observe that the decrease in precipitation induces a phase of surface uplift of landscapes to a new steady state condition (SS2); however, the details of the uplift histories (timing, rate) differ between the experiments according to Tp. We also observe a decrease in the erosion rate induced by the precipitation change; however, the timing and amplitude of this decrease vary according to Tp, defining a delayed and damped erosion signal. Our data show that the landscape response to precipitation change is dictated by a critical water-to-rock ratio (ratio of precipitation over uplift) that likely corresponds to a geomorphic threshold. Our study suggests that variations in precipitation that occur at a geological time scale (> 106 years) may have a weak impact on the erosion of landscapes and on the delivery of siliciclastic material to large rivers and sedimentary basins.

  5. Modelling the long term impact of climate change on the carbon budget of Lake Simcoe, Ontario using INCA-C.

    Science.gov (United States)

    Oni, S K; Futter, M N; Molot, L A; Dillon, P J

    2012-01-01

    This study presents a process-based model of dissolved organic carbon concentration ([DOC]) in catchments draining into Lake Simcoe, Ontario. INCA-C, the Integrated Catchment model for Carbon, incorporates carbon biogeochemical processes in a terrestrial system with hydrologic flow paths to simulate watershed wide [DOC]. The model successfully simulates present-day inter-annual and seasonal [DOC] dynamics in tributaries draining catchments with mixed or contrasting land cover in the Lake Simcoe watershed (LSW). The sensitivity of INCA-C to soil moisture, hydrologic controls and land uses within a watershed demonstrates its significance as a tool to explore pertinent environmental issues specific to the LSW. Projections of climate change under A1B and A2 SRES scenarios suggest a continuous monotonic increase in [DOC] in surface waters draining into Lake Simcoe. Large variations in seasonal DOC dynamics are predicted to occur during summer with a possibility of displacement of summer [DOC] maxima towards winter and a prolongation of summer [DOC] levels into the autumn. INCA-C also predicts possible increases in dissolved inorganic carbon in some tributaries with rising temperature suggesting increased CO(2) emissions from rivers as climate changes. Copyright © 2011 Elsevier B.V. All rights reserved.

  6. A Unified Satellite-Observation Polar Stratospheric Cloud (PSC) Database for Long-Term Climate-Change Studies

    Science.gov (United States)

    Fromm, Michael; Pitts, Michael; Alfred, Jerome

    2000-01-01

    This report summarizes the project team's activity and accomplishments during the period 12 February, 1999 - 12 February, 2000. The primary objective of this project was to create and test a generic algorithm for detecting polar stratospheric clouds (PSC), an algorithm that would permit creation of a unified, long term PSC database from a variety of solar occultation instruments that measure aerosol extinction near 1000 nm The second objective was to make a database of PSC observations and certain relevant related datasets. In this report we describe the algorithm, the data we are making available, and user access options. The remainder of this document provides the details of the algorithm and the database offering.

  7. Long-term effects of climate change on carbon storage and tree species composition in a dry deciduous forest.

    Science.gov (United States)

    Fekete, István; Lajtha, Kate; Kotroczó, Zsolt; Várbíró, Gábor; Varga, Csaba; Tóth, János Attila; Demeter, Ibolya; Veperdi, Gábor; Berki, Imre

    2017-08-01

    Forest vegetation and soils have been suggested as potentially important sinks for carbon (C) with appropriate management and thus are implicated as effective tools in stabilizing climate even with increasing anthropogenic release of CO 2 . Drought, however, which is often predicted to increase in models of future climate change, may limit net primary productio (NPP) of dry forest types, with unknown effects on soil C storage. We studied C dynamics of a deciduous temperate forest of Hungary that has been subject to significant decreases in precipitation and increases in temperature in recent decades. We resampled plots that were established in 1972 and repeated the full C inventory by analyzing more than 4 decades of data on the number of living trees, biomass of trees and shrubs, and soil C content. Our analyses show that the decline in number and biomass of oaks started around the end of the 1970s with a 71% reduction in the number of sessile oak stems by 2014. Projected growth in this forest, based on the yield table's data for Hungary, was 4.6 kg C/m 2 . Although new species emerged, this new growth and small increases in oak biomass resulted in only 1.9 kg C/m 2 increase over 41 years. The death of oaks increased inputs of coarse woody debris to the surface of the soil, much of which is still identifiable, and caused an increase of 15.5%, or 2.6 kg C/m 2 , in the top 1 m of soil. Stability of this fresh organic matter input to surface soil is unknown, but is likely to be low based on the results of a colocated woody litter decomposition study. The effects of a warmer and drier climate on the C balance of forests in this region will be felt for decades to come as woody litter inputs decay, and forest growth remains impeded. © 2017 John Wiley & Sons Ltd.

  8. Long-term Records of Pacific Salmon Abundance From Sediment Core Analysis: Relationships to Past Climatic Change, and Implications for the Future

    Science.gov (United States)

    Finney, B.

    2002-12-01

    above and below average strength of the Aleutian Low pressure system. During periods of stronger low pressure, sea surface temperature anomalies are warm in the northeast Pacific and cool in the central and northwest Pacific, a condition referred to as the positive phase of the Pacific Interdecadal Oscillation (PDO). Historically, during positive phases of the PDO Alaska salmon abundance is generally high. Consistent with this pattern, records of reconstructed sockeye salmon generally show higher abundance during warm periods over the past 300 years. However, the long-term trend suggests generally higher abundance during the cooler Little Ice Age, which southern Alaska glacial records suggest occurred between about 1200 - 1900 AD. The apparent complexity of salmon-climate relationships may be due to several factors. Long-term paleoclimate records from this region suggest additional modes of North Pacific climate variability, relative to the PDO. In addition, data on primary and secondary production in the Northeast Pacific Ocean indicates that climatic forcing has a direct impact on lower trophic levels, which subsequently affects salmon production. Thus records of ocean productivity, which are currently unavailable, may provide a mechanistic linkage between climate change and salmon abundance. The long-term perspective provided by the paleodata suggest that historical observations provide a limited understanding of how Pacific salmon respond to climatic change, and point to important areas of research necessary to better predict future responses.

  9. Long-Term Climate Change Assessment Task for the Hanford Site Permanent Isolation Barrier Development Program: Status through FY 1992

    International Nuclear Information System (INIS)

    Petersen, K.L.; Chatters, J.C.

    1993-07-01

    The Hanford Site Permanent Isolation Barrier Development Program (Barrier Development Program) was organized (Adams and Wing 1986) to develop the technology needed to provide an in-place disposal capability for the US Department of Energy at the Hanford Site in southeastern Washington. The goals of the Barrier Development Program are to provide defensible evidence that final barrier design(s) will adequately control water infiltration, plant and animal intrusion, and wind and water erosion for a minimum of 1,000 years; to isolate wastes from the accessible environment; and to use markers to warn inadvertent human intruders. Evidence for barrier performance will be obtained by conducting laboratory experiments, field tests, computer modeling, and other studies that establish confidence in the barrier's ability to meet its 1,000-year design life. The performance and stability of natural barrier analogs that have existed for several millennia and the reconstruction of climate changes during the past 10,000 to 125,000 years also will provide insight into bounding conditions of possible future changes and increase confidence in the barriers design. In the following discussion the term open-quotes long-termclose quotes references periods of time up to 1000's of years, distinguishing it from open-quotes short-termclose quotes weather patterns covering a decade or less. Specific activities focus on planning and conducting a series of studies and tests required to confirm key aspects of the barrier design. The effort is a collaborative one between scientists and engineers from Westinghouse Hanford Company (Westinghouse Hanford) and Pacific Northwest Laboratory (PNL) to design barriers to limit movement of radionuclides and other contaminants to the accessible environment for at least 1,000 years. These activities have been divided into 14 groups of tasks that aid in the complete development of protective barrier and warning marker system

  10. Accounting for wetlands loss in a changing climate in the estimation of long-term flood risks of Devils Lake, North Dakota

    Science.gov (United States)

    Gulbin, S.; Kirilenko, A.; Zhang, X.

    2016-12-01

    Endorheic (terminal) lakes with no water outlets are sensitive indicators of changes in climate and land cover in the watershed. Regional variation in precipitation pattern in the US Northern Great Plaines lead to a long term flooding of Devils Lake (DL), ND, leading to a 10-m water level rise in just two decades, with estimated flood mitigation costs of over $1 billion. While the climate change contribution to flooding has been established, the role of large scale land conversion to agriculture has not been researched. Wetlands play a very important part in hydrological balance by storing, absorbing and slowing peak water discharge. In ND, 49 % of wetlands are drained and converted to agriculture. We investigated the role of wetlands loss in DL flooding in current and future climate. The Soil and Water Assessment Tool (SWAT) was used to simulate streamflow in all DL watershed subbasins. The model was calibrated using the 1991-2000 USGS gauge data for the first 10 years of study period and validated for the second 10 years (2001-2010), resulting in a satisfactory model performance compared against the measured water discharge in five streams in the watershed and against observed DL water level. A set of wetland loss scenarios were created based on the historical data and the Compound Topographic Index. To emulate the historical and future climate conditions, an ensemble of CMIP5 weather integrations based on IPCC AR5 RCP scenarios was downscaled with the MarkSim weather simulator. Model simulations indicate that the land use change in the DL watershed increased the impacts of climate change on hydrology by further elevating DL water level. Conversely, wetland restoration reduce the flooding and moderates risks of a potential high-impact DL overspill to the Sheyenne River watershed. Further research will concentrate on differentiation of climate change impacts under different types of land use change scenarios.

  11. Modelling and forecasting long-term dynamics of Western Baltic macrobenthic fauna in relation to climate signals and environmental change

    Science.gov (United States)

    Gröger, Joachim; Rumohr, Heye

    2006-05-01

    Long-term macrobenthos data from Kiel Bight in the Western Baltic collected between 1968 and 2000 have been correlated with the winter NAO index (North Atlantic Oscillation Index) and other environmental data such as temperature, salinity and oxygen content in the bottom water in order to detect systematic patterns related to so far unexplained abiotic signals in the dynamics of zoobenthic species assemblages. The benthos data come from a cluster of five stations (Süderfahrt/ Millionenviertel) in Kiel Bay. Our investigations concentrated on the macrobenthic dynamics with a focus on the number of species m - 2 (species richness). Using logarithms and the time series analysis approach of Box/Jenkins (ARIMA modelling, transfer function modelling) it was shown that species richness was strongly influenced by the winter NAO (adjusted for a linear time trend within the 1968-2000 period) and salinity (with a shift/lag of four years). Bootstrapping experiments (i.e. sampling from the error process) and analysis of prediction power (by means of the one- or more-years leaving-out method) showed that the parameter estimates behaved in a stable way, leading to a relatively robust model.

  12. Long-term responses of rainforest erosional systems at different spatial scales to selective logging and climatic change

    Science.gov (United States)

    Walsh, R. P. D.; Bidin, K.; Blake, W. H.; Chappell, N. A.; Clarke, M. A.; Douglas, I.; Ghazali, R.; Sayer, A. M.; Suhaimi, J.; Tych, W.; Annammala, K. V.

    2011-01-01

    Long-term (21–30 years) erosional responses of rainforest terrain in the Upper Segama catchment, Sabah, to selective logging are assessed at slope, small and large catchment scales. In the 0.44 km2 Baru catchment, slope erosion measurements over 1990–2010 and sediment fingerprinting indicate that sediment sources 21 years after logging in 1989 are mainly road-linked, including fresh landslips and gullying of scars and toe deposits of 1994–1996 landslides. Analysis and modelling of 5–15 min stream-suspended sediment and discharge data demonstrate a reduction in storm-sediment response between 1996 and 2009, but not yet to pre-logging levels. An unmixing model using bed-sediment geochemical data indicates that 49 per cent of the 216 t km−2 a−1 2009 sediment yield comes from 10 per cent of its area affected by road-linked landslides. Fallout 210Pb and 137Cs values from a lateral bench core indicate that sedimentation rates in the 721 km2 Upper Segama catchment less than doubled with initially highly selective, low-slope logging in the 1980s, but rose 7–13 times when steep terrain was logged in 1992–1993 and 1999–2000. The need to keep steeplands under forest is emphasized if landsliding associated with current and predicted rises in extreme rainstorm magnitude-frequency is to be reduced in scale. PMID:22006973

  13. Climatic and biotic extreme events moderate long-term responses of above- and belowground sub-Arctic heathland communities to climate change

    NARCIS (Netherlands)

    Bokhorst, S.F.; Phoenix, G.K.; Berg, M.P.; Callaghan, T.V.; Kirby-Lambert, C.; Bjerke, J.W.

    2015-01-01

    Climate change impacts are not uniform across the Arctic region because interacting factors causes large variations in local ecosystem change. Extreme climatic events and population cycles of herbivores occur simultaneously against a background of gradual climate warming trends and can redirect

  14. Long-term rise of the Water Table in the Northeast US: Climate Variability, Land-Use Change, or Angry Beavers?

    Science.gov (United States)

    Boutt, D. F.

    2011-12-01

    The scientific evidence that humans are directly influencing the Earth's natural climate is increasingly compelling. Numerous studies suggest that climate change will lead to changes in the seasonality of surface water availability thereby increasing the need for groundwater development to offset those shortages. Research suggests that the Northeast region of the U.S. is experiencing significant changes to its' natural climate and hydrologic systems. Previous analysis of a long-term regional compilation of the water table response to the last 60 years of climate variability in New England documented a wide range of variability. The investigation evaluated the physical mechanisms, natural variability and response of aquifers in New England using 100 long term groundwater monitoring stations with 20 or more years of data coupled with 67 stream gages, 75 precipitation stations, and 43 temperature stations. Groundwater trends were calculated as normalized anomalies and analyzed with respect to regional compiled precipitation, temperature, and streamflow anomalies to understand the sensitivity of the aquifer systems to change. Interestingly, a trend and regression analysis demonstrate that water level fluctuations are producing statistically significant results with increasing water levels over at least the past thirty years at most (80 out of 100) well sites. In this contribution we investigate the causal mechanisms behind the observed ground water level trends using site-by-site land-use change assessments, cluster analysis, and spatial analysis of beaver populations (a possible proxy for beaver activity). Regionally, average annual precipitation has been slightly increasing since 1900, with 95% of the stations having statistically significant positive trends. Despite this, no correlation is observed between the magnitude of the annual precipitation trends and the magnitude of the groundwater level changes. Land-use change throughout the region has primarily taken

  15. Cross-regional prediction of long-term trajectory of stream water DOC response to climate change

    Science.gov (United States)

    H. Laudon; J.M. Buttle; S.K. Carey; J.J. McDonnell; K.J. McGuire; J. Seibert; J. Shanley; C. Soulsby; D. Tetzlaff

    2012-01-01

    There is no scientific consensus about how dissolved organic carbon (DOC) in surface waters is regulated. Here we combine recent literature data from 49 catchments with detailed stream and catchment process information from nine well established research catchments at mid- to high latitudes to examine the question of how climate controls stream water DOC. We show for...

  16. The Saturniidae of Barro Colorado Islands, Panama: A model taxon for studying the long-term effects of climate change?

    Czech Academy of Sciences Publication Activity Database

    Basset, Y.; Lamarre, Greg P. A.; Ratz, T.; Segar, Simon Tristram; Decaëns, T.; Rougerie, R.; Miller, S. E.; Perez, F.; Bobadilla, R.; Lopez, Y.; Ramirez, J. A.; Aiello, A.; Barrios, H.

    2017-01-01

    Roč. 7, č. 23 (2017), s. 9991-10004 ISSN 2045-7758 R&D Projects: GA ČR GB14-36098G EU Projects: European Commission(XE) 669609 - Diversity6continents Institutional support: RVO:60077344 Keywords : climatic anomalies * DNA barcoding * functional groups Subject RIV: EH - Ecology, Behaviour OBOR OECD: Ecology Impact factor: 2.440, year: 2016 http://onlinelibrary.wiley.com/doi/10.1002/ece3.3515/epdf

  17. Small-scale variations of climate change in mountainous forested terrain - a regional study from H.J. Andrews Long Term Ecological Research site in Oregon, USA

    Science.gov (United States)

    Honzakova, Katerina; Hoffmann, Peter; Jones, Julia; Thomas, Christoph

    2017-04-01

    There has been conflicting evidence as to whether high elevations are experiencing more pronounced climate warming than lower elevations in mountainous regions. In this study we analyze temperature records from H.J. Andrews Long Term Ecological Research, Oregon, USA and several nearby areas, comprising together 28 stations located in Cascade Mountains. The data, starting in 1958, are first checked for quality and homogenized using the Standard Normal Homogeneity Test. As a reference, composite climate time series based on the Global Historic Climate Network is created and together with cross-referencing against station records used to correct breaks and shifts in the data. In the next step, we investigate temperature patterns of the study site from 1958 to 2016 and compare them for valley and hill stations. In particular, we explore seasonality and inter-annual variability of the records and trends of the last day of frost. Additionally, 'cold' sums (positive and negative) are calculated to obtain a link between temperature and ecosystems' responses (such as budbreaks). So far, valley stations seem to be more prone to climate change than ridge or summit stations, contrary to current thinking. Building on previous knowledge, we attempt to provide physical explanations for the temperature records, focusing on wind patterns and associated phenomena such as cold air drainage and pooling. To aid this we analyze wind speed and direction data available for some of the stations since 1996, including seasonality and inter-annual variability of the observed flows.

  18. Long-Term Phenological Shifts in Raptor Migration and Climate

    Science.gov (United States)

    Jaffré, Mikaël; Beaugrand, Grégory; Goberville, Éric; Jiguet, Frédéric; Kjellén, Nils; Troost, Gerard; Dubois, Philippe J.; Leprêtre, Alain; Luczak, Christophe

    2013-01-01

    Climate change is having a discernible effect on many biological and ecological processes. Among observed changes, modifications in bird phenology have been widely documented. However, most studies have interpreted phenological shifts as gradual biological adjustments in response to the alteration of the thermal regime. Here we analysed a long-term dataset (1980-2010) of short-distance migratory raptors in five European regions. We revealed that the responses of these birds to climate-induced changes in autumn temperatures are abrupt and synchronous at a continental scale. We found that when the temperatures increased, birds delayed their mean passage date of autumn migration. Such delay, in addition to an earlier spring migration, suggests that a significant warming may induce an extension of the breeding-area residence time of migratory raptors, which may eventually lead to residency. PMID:24223888

  19. Long-term phenological shifts in raptor migration and climate.

    Directory of Open Access Journals (Sweden)

    Mikaël Jaffré

    Full Text Available Climate change is having a discernible effect on many biological and ecological processes. Among observed changes, modifications in bird phenology have been widely documented. However, most studies have interpreted phenological shifts as gradual biological adjustments in response to the alteration of the thermal regime. Here we analysed a long-term dataset (1980-2010 of short-distance migratory raptors in five European regions. We revealed that the responses of these birds to climate-induced changes in autumn temperatures are abrupt and synchronous at a continental scale. We found that when the temperatures increased, birds delayed their mean passage date of autumn migration. Such delay, in addition to an earlier spring migration, suggests that a significant warming may induce an extension of the breeding-area residence time of migratory raptors, which may eventually lead to residency.

  20. Can resistant coral-Symbiodinium associations enable coral communities to survive climate change? A study of a site exposed to long-term hot water input

    Directory of Open Access Journals (Sweden)

    Shashank Keshavmurthy

    2014-04-01

    Full Text Available Climate change has led to a decline in the health of corals and coral reefs around the world. Studies have shown that, while some corals can cope with natural and anthropogenic stressors either through resistance mechanisms of coral hosts or through sustainable relationships with Symbiodinium clades or types, many coral species cannot. Here, we show that the corals present in a reef in southern Taiwan, and exposed to long-term elevated seawater temperatures due to the presence of a nuclear power plant outlet (NPP OL, are unique in terms of species and associated Symbiodinium types. At shallow depths (<3 m, eleven coral genera elsewhere in Kenting predominantly found with Symbiodinium types C1 and C3 (stress sensitive were instead hosting Symbiodinium type D1a (stress tolerant or a mixture of Symbiodinium type C1/C3/C21a/C15 and Symbiodinium type D1a. Of the 16 coral genera that dominate the local reefs, two that are apparently unable to associate with Symbiodinium type D1a are not present at NPP OL at depths of <3 m. Two other genera present at NPP OL and other locations host a specific type of Symbiodinium type C15. These data imply that coral assemblages may have the capacity to maintain their presence at the generic level against long-term disturbances such as elevated seawater temperatures by acclimatization through successful association with a stress-tolerant Symbiodinium over time. However, at the community level it comes at the cost of some coral genera being lost, suggesting that species unable to associate with a stress-tolerant Symbiodinium are likely to become extinct locally and unfavorable shifts in coral communities are likely to occur under the impact of climate change.

  1. Radiocarbon age-offsets in an arctic lake reveal the long-term response of permafrost carbon to climate change

    Science.gov (United States)

    Gaglioti, Benjamin V.; Mann, Daniel H.; Jones, Benjamin M.; Pohlman, John W.; Kunz, Michael L.; Wooller, Matthew J.

    2014-01-01

    Continued warming of the Arctic may cause permafrost to thaw and speed the decomposition of large stores of soil organic carbon (OC), thereby accentuating global warming. However, it is unclear if recent warming has raised the current rates of permafrost OC release to anomalous levels or to what extent soil carbon release is sensitive to climate forcing. Here we use a time series of radiocarbon age-offsets (14C) between the bulk lake sediment and plant macrofossils deposited in an arctic lake as an archive for soil and permafrost OC release over the last 14,500 years. The lake traps and archives OC imported from the watershed and allows us to test whether prior warming events stimulated old carbon release and heightened age-offsets. Today, the age-offset (2 ka; thousand of calibrated years before A.D. 1950) and the depositional rate of ancient OC from the watershed into the lake are relatively low and similar to those during the Younger Dryas cold interval (occurring 12.9–11.7 ka). In contrast, age-offsets were higher (3.0–5.0 ka) when summer air temperatures were warmer than present during the Holocene Thermal Maximum (11.7–9.0 ka) and Bølling-Allerød periods (14.5–12.9 ka). During these warm times, permafrost thaw contributed to ancient OC depositional rates that were ~10 times greater than today. Although permafrost OC was vulnerable to climate warming in the past, we suggest surface soil organic horizons and peat are presently limiting summer thaw and carbon release. As a result, the temperature threshold to trigger widespread permafrost OC release is higher than during previous warming events.

  2. Assessing the long-term impact of subsidence and global climate change on emergency evacuation routes in coastal Louisiana.

    Science.gov (United States)

    2012-12-01

    Subsidence forecast models for coastal Louisiana were developed to estimate the change in surface elevations of evacuation routes for the years 2015, 2025, 2050, and 2100. Geophysical and anthropogenic subsidence estimates were derived from on-going ...

  3. Long-term climate monitoring by the global climate observing system

    International Nuclear Information System (INIS)

    Karl, T.R.

    1995-12-01

    Is the climate warming? Is the hydrologic cycle changing? Is the atmospheric/oceanic circulation changing? Is the climate becoming more variable or extreme? Is radiative forcing of the climate changing? are complex questions not only from the standpoint of a multi-variate problem, but because of the various aspects of spatial and temporal sampling that must be considered on a global scale. The development of a Global Climate Observing System (GCOS) offers the opportunity for scientists to do something about existing observing deficiencies in light of the importance of documenting long-term climate changes that may already be affected by anthropogenic changes of atmospheric composition and land use as well as other naturally occurring changes. As an important step toward improving the present inadequacies, a workshop was held to help define the long-term monitoring requirements minimally needed to address the five questions posed above, with special emphasis on detecting anthropogenic climate change and its potential impact on managed and unmanaged systems The workshop focussed on three broad areas related to long-term climate monitoring: (a) the scientific rationale for the long-term climate products (including their accuracy, resolution, and homogeneity) required from our observing systems as related to climate monitoring and climate change detection and attribution; (b) the status of long-term climate products and the observing systems from which these data are derived; and (c) implementation strategies necessary to fulfill item (a) in light of existing systems. Item (c) was treated more in terms of feasibility rather than as a specific implementation plan. figs., tabs., refs

  4. NDVI indicated long-term interannual changes in vegetation activities and their responses to climatic and anthropogenic factors in the Three Gorges Reservoir Region, China.

    Science.gov (United States)

    Wen, Zhaofei; Wu, Shengjun; Chen, Jilong; Lü, Mingquan

    2017-01-01

    Natural and social environmental changes in the China's Three Gorges Reservoir Region (TGRR) have received worldwide attention. Identifying interannual changes in vegetation activities in the TGRR is an important task for assessing the impact these changes have on the local ecosystem. We used long-term (1982-2011) satellite-derived Normalized Difference Vegetation Index (NDVI) datasets and climatic and anthropogenic factors to analyze the spatiotemporal patterns of vegetation activities in the TGRR, as well as their links to changes in temperature (TEM), precipitation (PRE), downward radiation (RAD), and anthropogenic activities. At the whole TGRR regional scale, a statistically significant overall uptrend in NDVI variations was observed in 1982-2011. More specifically, there were two distinct periods with different trends split by a breakpoint in 1991: NDVI first sharply increased prior to 1991, and then showed a relatively weak rate of increase after 1991. At the pixel scale, most parts of the TGRR experienced increasing NDVI before the 1990s but different trend change types after the 1990s: trends were positive in forests in the northeastern parts, but negative in farmland in southwest parts of the TGRR. The TEM warming trend was the main climate-related driver of uptrending NDVI variations pre-1990s, and decreasing PRE was the main climate factor (42%) influencing the mid-western farmland areas' NDVI variations post-1990s. We also found that anthropogenic factors such as population density, man-made ecological restoration, and urbanization have notable impacts on the TGRR's NDVI variations. For example, large overall trend slopes in NDVI were more likely to appear in TGRR regions with large fractions of ecological restoration within the last two decades. The findings of this study may help to build a better understanding of the mechanics of NDVI variations in the periods before and during TGDP construction for ongoing ecosystem monitoring and assessment in the

  5. Long-term changes in river system hydrology in Texas

    Directory of Open Access Journals (Sweden)

    Y. Zhang

    2018-06-01

    Full Text Available Climate change and human actives are recognized as a topical issue that change long-term water budget, flow-frequency, and storage-frequency characteristics of different river systems. Texas is characterized by extreme hydrologic variability both spatially and temporally. Meanwhile, population and economic growth and accompanying water resources development projects have greatly impacted river flows throughout Texas. The relative effects of climate change, water resources development, water use, and other factors on long-term changes in river flow, reservoir storage, evaporation, water use, and other components of the water budgets of different river basins of Texas have been simulated in this research using the monthly version of the Water Rights Analysis Package (WRAP modelling system with input databases sets from the Texas Commission on Environmental Quality (TCEQ and Texas Water Development Board (TWDB. The results show that long-term changes are minimal from analysis monthly precipitation depths. Evaporation rates vary greatly seasonally and for much of the state appear to have a gradually upward trend. River/reservoir system water budgets and river flow characteristics have changed significantly during the past 75 years in response to water resources development and use.

  6. Long-term changes in climatological calendar

    International Nuclear Information System (INIS)

    Jaagus, J.

    1997-01-01

    Trends in time series of climatic seasons in Tartu, Estonia, during 1891-1995 are analysed using regression analysis. Two intermediate seasons between autumn and winter (late autumn, early winter), and two ones between winter and spring (late winter and early spring) are determined. The climatic seasons correspond quite well to individual stages of annual cycling of nature. Results of linear regression analysis demonstrate changes in climatological calendar reflecting the influence of global warming. Climatic seasons of spring period have moved to earlier time, and seasons of autumn period to later time. Statistically significant trends were observed for beginning date of early spring (12 days earlier), summer (11 days earlier) and late autumn (8 days later). Beginning date of winter has shifted 12 days later. Duration of summer season has increased by two weeks and duration of winter season has decreased by the same time. (author)

  7. Phenology of species interactions in response to climate change: two case studies of plant-pollinator interactions using long-term data

    Science.gov (United States)

    McKinney, A. M.; Inouye, D. W.

    2012-12-01

    Climate change may alter the temporal overlap among interacting taxa with potential demographic consequences. Evidence of mistimed interactions in response to climate change, especially between plants and pollinators, is mixed, and few long-term datasets exist to test for changes in synchrony. Furthermore, advancements in flowering driven by climate change are especially pronounced at higher latitudes, so that migratory pollinators from lower latitudes may increasingly arrive at breeding grounds after the appearance of floral resources. We explored long-term shifts in phenological synchrony in two plant-pollinator systems:1) syrphid fly and flowering phenology in the Colorado Rocky Mountains, USA (1992-2011) and 2) hummingbird arrival relative to onset of early-season nectar resources in the Colorado Rocky Mountains (1975-2011) and the Santa Catalina Mountains, Arizona, USA (1984-2010). We investigated the abiotic cues associated with the phenology of the activity period of syrphid flies and their floral resources, including degree days above freezing, precipitation, and timing of snowmelt as potential explanatory variables. Timing of snowmelt was the best predictor of the onset of flowering and syrphid emergence. Snowmelt was also the best predictor of the end of flowering, while temperature and precipitation best predicted the end of the syrphid period. Both the onset and end of flowering advanced more rapidly than syrphids in response to earlier snowmelt. These different rates of phenological advancement resulted in increased temporal overlap between the flower and syrphid community in years of early snowmelt, because of longer flowering and fly activity periods during these years. If snowmelt continues to advance, temporal overlap between syrphids and their floral resources is therefore likely to increase. This case study shows that the phenology of interacting taxa may respond differently to climate cues, but that this does not necessarily lead to phenological

  8. Long-term simulation of temporal change of soil organic carbon in Denmark: comparison of three model performances under climate change

    DEFF Research Database (Denmark)

    Öztürk, Isik; Sharif, Behzad; Santhome, Sanmohan

    2018-01-01

    The temporal change in soil organic carbon (SOC) was analysed over an 80-year period based on climate change predictions of four regional circulation models under the International Panel on Climate Change (IPCC) A1B emission scenario in the 21st century. A 20-year (1991–2010) set of observed...... to the total variance of random variation was quantified. Statistical analysis showed that the crop-soil models are the main source for uncertainty in analysing soil C and N responses to climate change....

  9. Long-term trends in tourism climate index scores for 40 stations across Iran: the role of climate change and influence on tourism sustainability.

    Science.gov (United States)

    Roshan, Gholamreza; Yousefi, Robabe; Fitchett, Jennifer M

    2016-01-01

    Tourism is a rapidly growing international sector and relies intrinsically on an amenable climate to attract visitors. Climate change is likely to influence the locations preferred by tourists and the time of year of peak travel. This study investigates the effect of climate change on the Tourism Climate Index (TCI) for Iran. The paper first calculates the monthly TCI for 40 cities across Iran for each year from 1961 to 2010. Changes in the TCI over the study period for each of the cities are then explored. Increases in TCI are observed for at least one station in each month, whilst for some months no decreases occurred. For October, the maximum of 45% of stations demonstrated significant changes in TCI, whilst for December only 10% of stations demonstrated change. The stations Kashan, Orumiyeh, Shahrekord, Tabriz, Torbat-e-Heidarieh and Zahedan experienced significant increases in TCI for over 6 months. The beginning of the change in TCI is calculated to have occurred from 1970 to 1980 for all stations. Given the economic dependence on oil exports, the development of sustainable tourism in Iran is of importance. This critically requires the identification of locations most suitable for tourism, now and in the future, to guide strategic investment.

  10. Long-term runoff changes in regions of Slovakia

    International Nuclear Information System (INIS)

    Miklanek, Pavol; Pekarova; Pavla

    2004-01-01

    Mean annual runoff variability includes both natural and anthropogenic (climate change) impacts. Aim of the paper is to identify the long-term trends and the cyclic runoff components of selected Slovak rivers for the period 1931-2000, and of the Danube river for the period 1840-2000. The variability is analysed by the long-term runoff trends of 27 Slovak rivers for the period 1931-2000. The stations were included into the Slovak National Climate Program and they are supposed not to be influenced by anthropogenic activities except of possible climate change. Comparison of the monthly runoff series of the 27 rivers allowed us to draw 3 regions with different runoff trends on the territory of Slovakia (constant trend in Northern and Eastern Slovakia, slow decrease in Central Slovakia, and rapid decrease in Southern Slovakia; The identification of different cyclic components of the runoff series is included. The length of the series allows to identify the 22-year cycles as maximum. By means of the longer runoff series of the Danube river it is shown that the more dry periods occurred in the central Europe and Slovakia in mid 19 th century. The longer Danube series were used also to find the longer runoff cycles of about 31 and 46 years. The mean annual temperature in Europe was lower by 0.6 o C in mid 19 th century compared to 1990s. The temperature increase is put down to climate change impact. The driest period shown by Danube runoff series in mid 19 th century occurred before the start of the climate change. Therefore it is probable that the long-term runoff variability has its own dynamics as well. (Author)

  11. Climate Change and Potassium Effects Under Different N-Fertilization Input on Potato (Solanum tuberosum L.) Yield in a Long Term Field Experiment

    Science.gov (United States)

    László, Márton, ,, Dr.

    2010-05-01

    Climate change of Hungary was initiated about of 1850. Nowadays among the natural catastrophes, drought and flooding caused by over-abundant rainfall cause the greatest problems in field crop production. The droughts and the floods were experienced in the early eighties as well as today have drawn renewed attention to the analysis of this problem. The potato is demanding indicator crop of climate factors (temperature, rainfall) and soil nutrient status. Has a particularly high requirement for quantity of precipitation and for supply of soil potassium, nitrogen, phosphorus and magnesium. This paper reports the results achieved in the period from 1962 to 2001 of a long term small- plot fertilization experiment set up on acidic sandy brown forest soil at Nyírlugos in the Nyírség region in North- Eastern Hungary. Characteristics of the experiment soil were a pH (KCl) 4.5, humus 0.5%, CEC 5-10 mgeq 100g-1 in the ploughed layer. The topsoil was poor in all four macronutrient N, P, K and Mg. The mineral fertilization experiment involved 2 (genotype: Gülbaba and Aranyalma) x 2 (ploughed depth: 20 and 40 cm) x 16 (fertilizations: N, P, K, Mg) = 64 treatments in 8 replications, giving a total of 512 plots. The gross and net plot sizes were 10x5=50 m2 and 35.5 m2. The experimental designe was split-split-plot. The N levels were 0, 50, 100, 150 kg ha-1 year-1 and the P, K, Mg levels were 48, 150, 30 kg ha-1 year-1 P2O5, K2O, MgO in the form of 25% calcium ammonium nitrate, 18% superphosphate, 40% potassium chloride, and technological powdered magnesium sulphate. The forecrop every second year was rye. The groundwater level was at a depth of 2-3 m. From the 64 treatments, eight replications, altogether 512- experimental plots with 7 treatments and their 16 combinations are summarised of experiment period from 1962 to 1979. The main conclusions were as follows: 1. The experiment years (1962-1963, 1964-1965, 1966-1967, 1968-1969, 1970-1971, 1972-1973, 1974-1975, 1976

  12. UNEP-IOC-WMO-IUCN meeting of experts on a long-term global monitoring system of coastal and near-shore phenomena related to climate change, pilot projects and mangroves and coral reefs

    Energy Technology Data Exchange (ETDEWEB)

    1991-01-01

    This meeting was held to develop strategies for long-term global monitoring of coastal and near-shore phenomena related to climate change, specifically mangroves and coral reefs. The agenda included an overview of the Global Ocean Observing System (GOOS) initiative, modules and pilot phase activities. Action plans for the implementation of long-term monitoring of mangrove and coral reef ecosystems were developed including; potential impacts of climate change and sea level rise on mangroves and coral reefs, consideration of parameters, consideration of methodologies, relationships of proposed activities to relevant national, regional and international developments, consideration of monitoring sites, and future implementation.

  13. Dissolved oxygen stratification and response to thermal structure and long-term climate change in a large and deep subtropical reservoir (Lake Qiandaohu, China).

    Science.gov (United States)

    Zhang, Yunlin; Wu, Zhixu; Liu, Mingliang; He, Jianbo; Shi, Kun; Zhou, Yongqiang; Wang, Mingzhu; Liu, Xiaohan

    2015-05-15

    From January 2010 to March 2014, detailed depth profiles of water temperature, dissolved oxygen (DO), and chromophoric dissolved organic matter (CDOM) were collected at three sites in Lake Qiandaohu, a large, deep subtropical reservoir in China. Additionally, we assessed the changes in DO stratification over the past 61 years (1953-2013) based on our empirical models and long-term air temperature and transparency data. The DO concentration never fell below 2 mg/L, the critical value for anoxia, and the DO depth profiles were closely linked to the water temperature depth profiles. In the stable stratification period in summer and autumn, the significant increase in CDOM in the metalimnion explained the decrease in DO due to the oxygen consumed by CDOM. Well-developed oxygen stratification was detected at the three sites in spring, summer and autumn and was associated with thermal stratification. Oxycline depth was significantly negatively correlated with daily air temperature and thermocline thickness but significantly positively correlated with thermocline depth during the stratification weakness period (July-February). However, there were no significant correlations among these parameters during the stratification formation period (March-June). The increase of 1.67 °C in yearly average daily air temperature between 1980 and 2013 and the decrease of 0.78 m in Secchi disk depth caused a decrease of 1.65 m and 2.78 m in oxycline depth, respectively, facilitating oxygen stratification and decreasing water quality. Therefore, climate warming has had a substantial effect on water quality through changing the DO regime in Lake Qiandaohu. Copyright © 2015 Elsevier Ltd. All rights reserved.

  14. Impacts of fire and climate change on long-term nitrogen availability and forest productivity in the New Jersey Pine Barrens

    Science.gov (United States)

    Melissa S. Lucash; Robert M. Scheller; Alec M. Kretchun; Kenneth L. Clark; John. Hom

    2014-01-01

    Increased wildfires and temperatures due to climate change are expected to have profound effects on forest productivity and nitrogen (N) cycling. Forecasts about how wildfire and climate change will affect forests seldom consider N availability, which may limit forest response to climate change, particularly in fire-prone landscapes. The overall objective of this study...

  15. GENERALIZED MILANKOVITCH CYCLES AND LONG-TERM CLIMATIC HABITABILITY

    International Nuclear Information System (INIS)

    Spiegel, David S.; Dressing, Courtney D.; Raymond, Sean N.; Scharf, Caleb A.; Mitchell, Jonathan L.

    2010-01-01

    Although Earth's orbit is never far from circular, terrestrial planets around other stars might experience substantial changes in eccentricity. Eccentricity variations could lead to climate changes, including possible 'phase transitions' such as the snowball transition (or its opposite). There is evidence that Earth has gone through at least one globally frozen, 'snowball' state in the last billion years, which it is thought to have exited after several million years because global ice-cover shut off the carbonate-silicate cycle, thereby allowing greenhouse gases to build up to sufficient concentration to melt the ice. Due to the positive feedback caused by the high albedo of snow and ice, susceptibility to falling into snowball states might be a generic feature of water-rich planets with the capacity to host life. This paper has two main thrusts. First, we revisit one-dimensional energy balance climate models as tools for probing possible climates of exoplanets, investigate the dimensional scaling of such models, and introduce a simple algorithm to treat the melting of the ice layer on a globally frozen planet. We show that if a terrestrial planet undergoes Milankovitch-like oscillations of eccentricity that are of great enough magnitude, it could melt out of a snowball state. Second, we examine the kinds of variations of eccentricity that a terrestrial planet might experience due to the gravitational influence of a giant companion. We show that a giant planet on a sufficiently eccentric orbit can excite extreme eccentricity oscillations in the orbit of a habitable terrestrial planet. More generally, these two results demonstrate that the long-term habitability (and astronomical observables) of a terrestrial planet can depend on the detailed architecture of the planetary system in which it resides.

  16. Comparative study of different stochastic weather generators for long-term climate data simulation

    Science.gov (United States)

    Climate is one of the single most important factors affecting watershed ecosystems and water resources. The effect of climate variability and change has been studied extensively in some places; in many places, however, assessments are hampered by limited availability of long term continuous climate ...

  17. Long-term effects of climate change on the hydrological system of a lowland area at the German North Sea coast

    Science.gov (United States)

    Graeff, Thomas; Baroni, Gabriele; Krause, Stefan

    2014-05-01

    Coastal areas are highly vulnerable to the impacts of climate change. In particular for the winter season, global sea level rise is expected to be combined with increased precipitation and higher storm surge frequency. During summer, due to the increase of temperature, enhanced evapotranspiration with an increase of groundwater intrusion has been observed. It is expected that the salinization of the surface will rise under drier conditions by upward seeping groundwater. Coastal water resource management requires a better understanding and predictions of these dynamic systems. Therefore, a long-term monitoring programme has been established at the German North Sea coast, located at the estuary of the River Ems. The research area is dominated by a dense canal system that is regulated by pumping stations and tidal gates. Landuse of the area is mainly dairy farming with 30 % of the area below sea level. The underlying aquifer is confined and brackish, and it is connected to the surface water by geological faults of old paleo-channels. Observations in those areas indicate a high salinity with concentrations peaking during the summer period. This study investigates the effects of climate change on water balance and salt transport by applying regional climate models (RCMs) based on the IPCC emission scenarios for the period until 2100 as drivers for a hydrological and solute transport model. To investigate the impact of different meteorological scenarios, the RCM results for the climate scenarios A1B, A2 and B1 are used to cover an increase of future temperature between 1 and 3.5 K. As changes in water level and salinity are expected to influence vegetation patterns (and water management aims to guaranty agricultural use) two alternative landuse scenarios are considered. The first scenario assumes that the technological level of the management will be adapted to rainfall and sea level but without additional drainage from the hinterland to reduce salt water concentration

  18. Long-term wave climate at DanWEC

    DEFF Research Database (Denmark)

    Tetu, Amélie; Kofoed, Jens Peter

    andthe current network of sensors are also presented. The numerical model used toobtain the 35 years hindcast data is introduced together with its validation againstbuoy-measured data and with the description of the dataset utilised for thelong-term climate definition. The recommendations from [IEC 62600...... buoys are continuously recorded and the data is analysed on a quarterly basis. The directional wave measuring buoys were first installed in March 2015. As two years is not sufficient for long-term wave climate definition, modelled data was more appropriate for the task. Thelong-term wave climate around...... Hanstholm is defined in the present report using the hindcast data from the MIKE 21 Spectral Wave model provided by DHI, one of the partners of the project. Before the actual wave climate definition, a description of the site includinglocation and bathymetry is included. The historical wave data of the area...

  19. Beyond Quarterly Earnings: Preparing the Business Community for Long-term Climate Risks

    Science.gov (United States)

    Carlson, C.; Goldman, G. T.

    2014-12-01

    The business community stands to be highly impacted by climate change. In both short and long-term timescales, climate change presents material and financial risks to companies in diverse economic sectors. How the private sector accounts for long-term risks while making short-term decisions about operations is a complex challenge. Companies are accountable to shareholders and must report performance to them on a quarterly basis. At the same time, company investors are exposed to long-term climate-related risks and face losses if companies fail to prepare for climate impacts. The US Securities and Exchange Commission (SEC) obligates publicly traded companies to discuss risks that might materially affect their business and since 2010, the agency recommends that companies consider and discuss any significant risks to their business from climate change. Some companies have complied with this guidance and comprehensively analyze potential climate change impacts, yet others fail to consider climate change at all. Such omissions leave companies without plans for addressing future risks and expose investors and the public to potential catastrophic events from climate change impacts. Climate risk projections can inform companies about the vulnerability of their facilities, supply chains, transportation pathways, and other assets. Such projections can help put climate-related risks in terms of material costs for companies and their investors. Focusing on the vulnerability of coastal facilities, we will use climate change impact projections to demonstrate the economic impacts of climate change faced by the private sector. These risks are then compared to company disclosures to the SEC to assess the degree to which companies have considered their vulnerability to climate change. Finally, we will discuss ways that companies can better assess and manage long-term climate risks.

  20. Contrasting responses to long-term climate change of carbon flows to benthic consumers in two different sized lakes in the Baltic area.

    Science.gov (United States)

    Belle, Simon; Freiberg, Rene; Poska, Anneli; Agasild, Helen; Alliksaar, Tiiu; Tõnno, Ilmar

    2018-05-01

    The study of lake sediments and archived biological remains is a promising approach to better understand the impacts of climate change on aquatic ecosystems. Small lakes have been shown to be strongly sensitive to past climate change, but similar information is lacking for large lakes. By identifying responses to climate change of carbon flows through benthic food web in two different sized lakes, we aimed to understand how lake morphometry can mediate the effects of climate change. We reconstructed the dynamics of phytoplankton community composition and carbon resources sustaining chironomid biomass during the Holocene from the combined analysis of sedimentary pigment quantification and carbon stable isotopic composition of subfossil chironomid head capsules (δ13CHC) in a large lake in the Baltic area (Estonia). Our results showed that chironomid biomass in the large lake was mainly sustained by phytoplankton, with no significant relationship between δ13CHC values and temperature fluctuations. We suggest that lake morphometry (including distance of the sampling zone to the shoreline, and lake volume for primary producers) mediates the effects of climate change, making large lakes less sensitive to climate change. Complementary studies are needed to better understand differences in organic matter dynamics in different sized lakes and to characterize the response of the aquatic carbon cycle to past climate change.

  1. Disentangling the Long-term Effects of Climate Change and Forest Structure and Species Composition on Streamflow Across the Eastern US

    Science.gov (United States)

    Caldwell, P.; Elliott, K.; Hartsell, A.; Miniat, C.

    2016-12-01

    Climate change and disturbances are threatening the ability of forested watersheds to provide the clean, reliable, and abundant fresh water necessary to support aquatic ecosystems and a growing human population. Forested watersheds in the eastern US have undergone significant change over the 20th century due to natural and introduced disturbances and a legacy of land use. We hypothesize that changes in forest age and species composition (i.e., forest change) associated with these disturbances may have altered forest water use and thus streamflow (Q) due to inherent differences in transpiration among species and forest ages. To test this hypothesis, we quantified changes in Q from 1960 to 2012 in 202 US Geological Survey forested reference watersheds across the eastern US, and separated the effect of changes in climate from forest change using Auto-Regressive Integrated Moving Average (ARIMA) time series modeling. We linked changes in Q to forest disturbance, forest ages and species composition using the Landsat-based North American Forest Dynamics dataset and plot-level USDA Forest Service Forest Inventory and Analysis (FIA) data. We found that 172 of the 202 sites (85%) exhibited changes in Q not accounted for by climate that we attributed to forest change and/or land use change. Among these, 76 (44%) had declining Q due to forest change (mostly in the southeastern US) while 96 (56%) had increasing Q (mostly in the mid-Atlantic and northeastern US). Across the 172 sites with forest-related changes in Q, 34% had at least 10% of the watershed area disturbed at least once from 1986-2010. In a case study of three watersheds, FIA data indicated that changes in forest structure and species composition explained observed changes in Q beyond climate effects. Our results suggest that forest-related changes in Q may have significant implications for water supply in the region and may inform forest management strategies to mitigate climate change impacts on water resources.

  2. Long-term trends at the Boknis Eck time series station (Baltic Sea, 1957–2013: does climate change counteract the decline in eutrophication?

    Directory of Open Access Journals (Sweden)

    S. T. Lennartz

    2014-11-01

    Full Text Available The Boknis Eck (BE time series station, initiated in 1957, is one of the longest-operated time series stations worldwide. We present the first statistical evaluation of a data set of nine physical, chemical and biological parameters in the period of 1957–2013. In the past three to five decades, all of the measured parameters underwent significant long-term changes. Most striking is an ongoing decline in bottom water oxygen concentration, despite a significant decrease of nutrient and chlorophyll a concentrations. Temperature-enhanced oxygen consumption in the bottom water and a prolongation of the stratification period are discussed as possible reasons for the ongoing oxygen decline despite declining eutrophication. Observations at the BE station were compared with model output of the Kiel Baltic Sea Ice Ocean Model (BSIOM. Reproduced trends were in good agreement with observed trends for temperature and oxygen, but generally the oxygen concentration at the bottom has been overestimated.

  3. Modeling the impact of climate change in Germany with biosphere models for long-term safety assessment of nuclear waste repositories

    International Nuclear Information System (INIS)

    Staudt, C.; Semiochkina, N.; Kaiser, J.C.; Pröhl, G.

    2013-01-01

    Biosphere models are used to evaluate the exposure of populations to radionuclides from a deep geological repository. Since the time frame for assessments of long-time disposal safety is 1 million years, potential future climate changes need to be accounted for. Potential future climate conditions were defined for northern Germany according to model results from the BIOCLIM project. Nine present day reference climate regions were defined to cover those future climate conditions. A biosphere model was developed according to the BIOMASS methodology of the IAEA and model parameters were adjusted to the conditions at the reference climate regions. The model includes exposure pathways common to those reference climate regions in a stylized biosphere and relevant to the exposure of a hypothetical self-sustaining population at the site of potential radionuclide contamination from a deep geological repository. The end points of the model are Biosphere Dose Conversion factors (BDCF) for a range of radionuclides and scenarios normalized for a constant radionuclide concentration in near-surface groundwater. Model results suggest an increased exposure of in dry climate regions with a high impact of drinking water consumption rates and the amount of irrigation water used for agriculture. - Highlights: ► We model Biosphere Dose Conversion Factors for a representative group exposed to radionuclides from a waste repository. ► The BDCF are modeled for different soil types. ► One model is used for the assessment of the influence of climate change during the disposal time frame.

  4. Long-term variations in sediment heavy metals of a reservoir with changing trophic states: Implications for the impact of climate change.

    Science.gov (United States)

    Wu, Qiong; Qi, Jun; Xia, Xinghui

    2017-12-31

    Two dated sediment cores from the Miyun Reservoir of Beijing in China were analyzed to reconstruct the pollution history of heavy metals including cadmium (Cd), chromium (Cr), iron (Fe), nickel (Ni), and zinc (Zn) as well as phosphorus (P). Enrichment factor (EF) and geoaccumulation index (I geo ) were applied to assess the enrichment status of heavy metals. Average EF and I geo values indicated that the studied heavy metals in the sediments mainly originated from non-point source pollution and soil-water erosion, showing low ecological risks. In addition, correlation analysis and principal component analysis (PCA) identified that Cd, Zn, and P were mainly from agricultural diffusion pollution caused by utilization of the phosphate fertilizer; Zn, Ni, and Cr originated from soil erosion. PCA analysis was further conducted to investigate the relationships among meteorological factors, algae-dominant total organic carbon (TOC), and heavy metals. Results showed that algae-dominant TOC had strong positive correlation with temperature, which can be explained by that increased temperature accelerated the growth of algae. Meanwhile the opposite loadings between algae-dominant TOC and heavy metal suggested that primary production played an important role in migration and transformation of metals. Moreover, stepwise multiple regression models showed that Fe was sensitive to temperature, which accounted for approximately 39.0% and 40.1% of the variations in Fe of two sediment cores, respectively. Fe showed significant decreasing trends during the past 50years. Reductive environment of water-sediment interface caused by increasing temperature probably contributed to the restoration of ferric iron, resulting in the release of soluble Fe to overlying waters. Future climate change with elevated temperature and extreme weather events will aggravate the ecological risk of heavy metals in water environment due to the enhanced leaching effect and non-point source pollution as well

  5. Modeling the impact of climate change in Germany with biosphere models for long-term safety assessment of nuclear waste repositories.

    Science.gov (United States)

    Staudt, C; Semiochkina, N; Kaiser, J C; Pröhl, G

    2013-01-01

    Biosphere models are used to evaluate the exposure of populations to radionuclides from a deep geological repository. Since the time frame for assessments of long-time disposal safety is 1 million years, potential future climate changes need to be accounted for. Potential future climate conditions were defined for northern Germany according to model results from the BIOCLIM project. Nine present day reference climate regions were defined to cover those future climate conditions. A biosphere model was developed according to the BIOMASS methodology of the IAEA and model parameters were adjusted to the conditions at the reference climate regions. The model includes exposure pathways common to those reference climate regions in a stylized biosphere and relevant to the exposure of a hypothetical self-sustaining population at the site of potential radionuclide contamination from a deep geological repository. The end points of the model are Biosphere Dose Conversion factors (BDCF) for a range of radionuclides and scenarios normalized for a constant radionuclide concentration in near-surface groundwater. Model results suggest an increased exposure of in dry climate regions with a high impact of drinking water consumption rates and the amount of irrigation water used for agriculture. Copyright © 2012 Elsevier Ltd. All rights reserved.

  6. Changing incentives for long-term gas contracts

    International Nuclear Information System (INIS)

    Bohi, D.R.

    1992-01-01

    There is much concern about the absence of long-term gas contracts with fixed price and quantity conditions, which until recent years was the standard way of doing business in the gas industry. These types of contracts performed a valuable service in the development of the gas industry, and there comparative absence today is sometimes thought to be one reason for the current malaise in the industry. One hears the argument that there must be some kind of 'market failure' that prevents buyers and sellers from entering into these long term arrangements, and recent changes in state and federal regulations are often cited as the cause of the problem. The purpose of the author's remarks is to argue that what is taken as a breakdown in the market may be simply a reaction to a decline in economic incentives to enter into long-term contracts with rigid price and quantity terms. This is, in other words, simply one more aspect of change in the gas business that Frank Heintz referred to in his opening remarks this morning. The author starts by giving a brief description of the motives for engaging in long-term contracts, and then describes how incentives to use long-term contracts have declined for both gas buyers and gas sellers. He concludes that the decline in the use of long-term contracts is not cause for regulatory concern, but a result of the continuing transformation of the gas business to one that more closely resembles other commodity markets

  7. Near-Term Actions to Address Long-Term Climate Risk

    Science.gov (United States)

    Lempert, R. J.

    2014-12-01

    Addressing climate change requires effective long-term policy making, which occurs when reflecting on potential events decades or more in the future causes policy makers to choose near-term actions different than those they would otherwise pursue. Contrary to some expectations, policy makers do sometimes make such long-term decisions, but not as commonly and successfully as climate change may require. In recent years however, the new capabilities of analytic decision support tools, combined with improved understanding of cognitive and organizational behaviors, has significantly improved the methods available for organizations to manage longer-term climate risks. In particular, these tools allow decision makers to understand what near-term actions consistently contribute to achieving both short- and long-term societal goals, even in the face of deep uncertainty regarding the long-term future. This talk will describe applications of these approaches for infrastructure, water, and flood risk management planning, as well as studies of how near-term choices about policy architectures can affect long-term greenhouse gas emission reduction pathways.

  8. Long-term projections of temperature-related mortality risks for ischemic stroke, hemorrhagic stroke, and acute ischemic heart disease under changing climate in Beijing, China.

    Science.gov (United States)

    Li, Tiantian; Horton, Radley M; Bader, Daniel A; Liu, Fangchao; Sun, Qinghua; Kinney, Patrick L

    2018-03-01

    Changing climates have been causing variations in the number of global ischemic heart disease and stroke incidences, and will continue to affect disease occurrence in the future. To project temperature-related mortality for acute ischemic heart disease, and ischemic and hemorrhagic stroke with concomitant climate warming. We estimated the exposure-response relationship between daily cause-specific mortality and daily mean temperature in Beijing. We utilized outputs from 31 downscaled climate models and two representative concentration pathways (RCPs) for the 2020s, 2050s, and 2080s. This strategy was used to estimate future net temperature along with heat- and cold-related deaths. The results for predicted temperature-related deaths were subsequently contrasted with the baseline period. In the 2080s, using the RCP8.5 and no population variation scenarios, the net total number of annual temperature-related deaths exhibited a median value of 637 (with a range across models of 434-874) for ischemic stroke; this is an increase of approximately 100% compared with the 1980s. The median number of projected annual temperature-related deaths was 660 (with a range across models of 580-745) for hemorrhagic stroke (virtually no change compared with the 1980s), and 1683 (with a range across models of 1351-2002) for acute ischemic heart disease (a slight increase of approximately 20% compared with the 1980s). In the 2080s, the monthly death projection for hemorrhagic stroke and acute ischemic heart disease showed that the largest absolute changes occurred in summer and winter while the largest absolute changes for ischemic stroke occurred in summer. We projected that the temperature-related mortality associated with ischemic stroke will increase dramatically due to climate warming. However, projected temperature-related mortality pertaining to acute ischemic heart disease and hemorrhagic stroke should remain relatively stable over time. Copyright © 2017 Elsevier Ltd. All rights

  9. Backcasting long-term climate data: evaluation of hypothesis

    Science.gov (United States)

    Saghafian, Bahram; Aghbalaghi, Sara Ghasemi; Nasseri, Mohsen

    2018-05-01

    Most often than not, incomplete datasets or short-term recorded data in vast regions impedes reliable climate and water studies. Various methods, such as simple correlation with stations having long-term time series, are practiced to infill or extend the period of observation at stations with missing or short-term data. In the current paper and for the first time, the hypothesis on the feasibility of extending the downscaling concept to backcast local observation records using large-scale atmospheric predictors is examined. Backcasting is coined here to contrast forecasting/projection; the former is implied to reconstruct in the past, while the latter represents projection in the future. To assess our hypotheses, daily and monthly statistical downscaling models were employed to reconstruct past precipitation data and lengthen the data period. Urmia and Tabriz synoptic stations, located in northwestern Iran, constituted two case study stations. SDSM and data-mining downscaling model (DMDM) daily as well as the group method of data handling (GMDH) and model tree (Mp5) monthly downscaling models were trained with National Center for Environmental Prediction (NCEP) data. After training, reconstructed precipitation data of the past was validated against observed data. Then, the data was fully extended to the 1948 to 2009 period corresponding to available NCEP data period. The results showed that DMDM performed superior in generation of monthly average precipitation compared with the SDSM, Mp5, and GMDH models, although none of the models could preserve the monthly variance. This overall confirms practical value of the proposed approach in extension of the past historic data, particularly for long-term climatological and water budget studies.

  10. Quantification and Mitigation of Long-Term Impacts of Urbanization and Climate Change in the Tropical Coastal City of San Juan, Puerto Rico

    Science.gov (United States)

    Comarazamy, Daniel; Gonzalez, Jorge E.; Luvall, Jeffrey C.

    2014-01-01

    Urbanization, along with other cases of land cover and land use changes, has significant climate impacts in tropical regions with the added complexity of occurring within the context of global warming. The individual and combined effects of these two factors on the surface energy balance of a tropical city are investigated by use of an integrated atmospheric modeling approach, taking the San Juan Metropolitan Area (SJMA), Puerto Rico as the test case. To achieve this goal, an ensemble of climate and weather simulations is performed, with the climate scenarios combining urban development and sprawl with regional climate change over the past 50 years, and the short-term simulations designed to test the sensitivity to different urban vegetation configurations as mitigating alternatives. As indicator of change, we use the thermal response number (TRN), which is a measure of the sensible heating to the thermal storage of a surface or region, and the Bowen ratio, which is defined as the ratio of sensible to latent heat fluxes. The TRN of the area occupied by the SJMA has decreased as a consequence of replacing the low land coastal plain vegetation with man made materials, indicating that it takes less energy to raise the surface temperature of the urban area, whereas the TRN of forested regions has remained virtually unchanged. The global warming signal also has effects on the thermal response of the SJMA, where dryer current conditions generate lower TRN values. Differences due to global warming are more evident in the Bowen ratio pattern, mostly associated with the drier present conditions observed and its effects on sensible and latent heat fluxes. In terms of testing different mitigation strategies, the short-term simulations show that the urban area is more efficient in partitioning surface energy balance terms when green roofs are specified, as opposed to including vegetation inside the urban core.

  11. Applying a Multi-Model Ensemble Method for Long-Term Runoff Prediction under Climate Change Scenarios for the Yellow River Basin, China

    Directory of Open Access Journals (Sweden)

    Linus Zhang

    2018-03-01

    Full Text Available Given the substantial impacts that are expected due to climate change, it is crucial that accurate rainfall–runoff results are provided for various decision-making purposes. However, these modeling results often generate uncertainty or bias due to the imperfect character of individual models. In this paper, a genetic algorithm together with a Bayesian model averaging method are employed to provide a multi-model ensemble (MME and combined runoff prediction under climate change scenarios produced from eight rainfall–runoff models for the Yellow River Basin. The results show that the multi-model ensemble method, especially the genetic algorithm method, can produce more reliable predictions than the other considered rainfall–runoff models. These results show that it is possible to reduce the uncertainty and thus improve the accuracy for future projections using different models because an MME approach evens out the bias involved in the individual model. For the study area, the final combined predictions reveal that less runoff is expected under most climatic scenarios, which will threaten water security of the basin.

  12. Coordinated approaches to quantify long-term ecosystem dynamics in response to global change

    DEFF Research Database (Denmark)

    Liu, Y.; Melillo, J.; Niu, S.

    2011-01-01

    a coordinated approach that combines long-term, large-scale global change experiments with process studies and modeling. Long-term global change manipulative experiments, especially in high-priority ecosystems such as tropical forests and high-latitude regions, are essential to maximize information gain......Many serious ecosystem consequences of climate change will take decades or even centuries to emerge. Long-term ecological responses to global change are strongly regulated by slow processes, such as changes in species composition, carbon dynamics in soil and by long-lived plants, and accumulation...... to be the most effective strategy to gain the best information on long-term ecosystem dynamics in response to global change....

  13. Long-Term Soil Chemistry Changes in Aggrading Forest Ecosystems

    Science.gov (United States)

    Jennifer D. Knoepp; Wayne T. Swank

    1994-01-01

    Assessing potential long-term forest productivity requires identification of the processes regulating chemical changes in forest soils. We resampled the litter layer and upper two mineral soil horizons, A and AB/BA, in two aggrading southern Appalachian watersheds 20 yr after an earlier sampling. Soils from a mixed-hardwood watershed exhibited a small but significant...

  14. The Siberian High and Arctic Sea Ice: Long-term Climate Change and Impacts on Air Pollution during Wintertime in China

    Science.gov (United States)

    Long, X.; Zhao, S.; Feng, T.; Tie, X.; Li, G.

    2017-12-01

    China has undergone severe air pollution during wintertime as national industrialization and urbanization have been increasingly developed in the past three decades. It has been suggested that high emission and adverse weather patterns contribute to wintertime air pollution. Recent studies propose that climate change and Arctic sea ice loss likely lead to extreme haze events in winter. Here we use two reanalysis and observational datasets to present the trends of Siberian High (SH) intensity over Eurasia, and Arctic temperature and sea ice. The results show the Arctic region of Asia is becoming warming accompanied by a rapid decline of sea ice while Eurasia is cooling and SH intensity is gradually enhancing. Wind patterns induced by these changes cause straight westerly prevailing over Eurasia at the year of weak SH while strengthened northerly winds at the year of strong SH. Therefore, we utilize regional dynamical and chemical WRF-Chem model to determine the impact of SH intensity difference on wintertime air pollution in China. As a result, enhancing northerly winds at the year of strong SH rapidly dilute and transport air pollution, causing a decline of 50 - 400 µg m-3 PM2.5 concentrations relative to that at the year of weak SH. We also assess the impact of emission reduction to half the current level on air pollution. The results show that emission reduction by 50% has an equivalent impact as the variability of SH intensity. This suggests that climate change over Eurasia has largely offset the negative impact of emission on air pollution and it is urgently needed to take measures to mitigate air pollution. In view of current high emission scenario in China, it will be a long way to effectively mitigate, or ultimately prevent wintertime air pollution.

  15. Interannual and long-term changes in the trophic state of a multibasin lake: Effects of morphology, climate, winter aeration, and beaver activity

    Science.gov (United States)

    Robertson, Dale M.; Rose, William; Reneau, Paul C.

    2016-01-01

    Little St. Germain Lake (LSG), a relatively pristine multibasin lake in Wisconsin, USA, was examined to determine how morphologic (internal), climatic (external), anthropogenic (winter aeration), and natural (beaver activity) factors affect the trophic state (phosphorus, P; chlorophyll, CHL; and Secchi depth, SD) of each of its basins. Basins intercepting the main flow and external P sources had highest P and CHL and shallowest SD. Internal loading in shallow, polymictic basins caused P and CHL to increase and SD to decrease as summer progressed. Winter aeration used to eliminate winterkill increased summer internal P loading and decreased water quality, while reductions in upstream beaver impoundments had little effect on water quality. Variations in air temperature and precipitation affected each basin differently. Warmer air temperatures increased productivity throughout the lake and decreased clarity in less eutrophic basins. Increased precipitation increased P in the basins intercepting the main flow but had little effect on the isolated deep West Bay. These relations are used to project effects of future climatic changes on LSG and other temperate lakes.

  16. Coordinated approaches to quantify long-term ecosystem dynamics in response to global change

    Science.gov (United States)

    Yiqi Luo; Jerry Melillo; Shuli Niu; Claus Beier; James S. Clark; Aime E.T. Classen; Eric Dividson; Jeffrey S. Dukes; R. Dave Evans; Christopher B. Field; Claudia I. Czimczik; Michael Keller; Bruce A. Kimball; Lara M. Kueppers; Richard J. Norby; Shannon L. Pelini; Elise Pendall; Edward Rastetter; Johan Six; Melinda Smith; Mark G. Tjoelker; Margaret S. Torn

    2011-01-01

    Many serious ecosystem consequences of climate change will take decades or even centuries to emerge. Long-term ecological responses to global change are strongly regulated by slow processes, such as changes in species composition, carbon dynamics in soil and by long-lived plants, and accumulation of nutrient capitals. Understanding and predicting these processes...

  17. Shifting Global Climate Governance: Creating Long-Term Goals Through UNFCCC Article 2

    Directory of Open Access Journals (Sweden)

    P. Brian Fisher

    2011-12-01

    Full Text Available I argue that the long-term risk of global climate change has been mischaracterized as an environmental issue, and therefore, solutions based solely on national emission targets will be ineffective. Thus, this paper argues for establishing long-term goals emphasizing both adaptation and clean energy to generate equitable and effective global climate policy that addresses this fundamental threat. This requires defining and operationalizing the overall objective contained in Article 2 of the United Nations Framework Convention on Climate Change. A second key aspect to operationalizing Article 2 is to understand those ‘particularly vulnerable’ as declared in the Article and in various climate agreements. Once operationalized, these long-term objectives can be achieved through approaches that emphasize the development of clean energy (and concomitant technology, and adaptation within vulnerable communities in their local context. It necessitates dropping formal mechanisms at the current core of the regime designed to regulate national emissions, and instead build the core of the regime around the ‘stabilization’ of both the climate system through clean energy and vulnerable people through effective adaptation.

  18. Implication of Paris Agreement in the context of long-term climate mitigation goals.

    Science.gov (United States)

    Fujimori, Shinichiro; Su, Xuanming; Liu, Jing-Yu; Hasegawa, Tomoko; Takahashi, Kiyoshi; Masui, Toshihiko; Takimi, Maho

    2016-01-01

    The Paris Agreement confirmed the global aim to achieve a long-term climate goal, in which the global increase in mean temperature is kept below 2 °C compared to the preindustrial level. We investigated the implications of the near-term emissions targets (for around the year 2030) in the context of the long-term climate mitigation goal using the Asia-Pacific Integrated Model framework. To achieve the 2 °C goal, a large greenhouse gas emissions reduction is required, either in the early or latter half of this century. In the mid-term (from 2030 to 2050), it may be necessary to consider rapid changes to the existing energy or socioeconomic systems, while long-term measures (after 2050) will rely on the substantial use of biomass combined with carbon capture and storage technology or afforestation, which will eventually realize so-called negative CO2 emissions. With respect to the policy context, two suggestions are provided here. The first is the review and revision of the nationally determined contributions (NDCs) in 2020, with an additional reduction target to the current NDCs being one workable alternative. The second suggestion is a concrete and numerical mid-term emissions reduction target, for example to be met by 2040 or 2050, which could also help to achieve the long-term climate goal.

  19. A review of the possible impacts of long-term oceanic and climate changes and fishing mortality on recruitment of anguillid eels of the Northern Hemisphere.

    Science.gov (United States)

    Knights, B

    2003-07-01

    Possible causes of declines in recruitment of European, American and Japanese eels to continental waters are reviewed. Negative correlations between the Den Oever glass eel recruitment index (DOI) and the North Atlantic Oscillation Index since 1938 are discussed, together with older anecdotal evidence. Correlations are established between the DOI and sea surface temperature anomalies at 100-250 m between 1952 and 1995 in the Sargasso Sea/Sub-Tropical Gyre (STG) spawning area. It is hypothesised that, associated with global warming trends, STG warming inhibits spring thermocline mixing and nutrient circulation, with negative impacts on productivity and hence food for leptocephalus larvae. Concurrent gyre spin-up also affects major currents and slowing of oceanic migration has probably enhanced starvation and predation losses. Local factors, such as unfavourable wind-driven currents, can also affect recruitment of glass eels on continental shelves. In contrast, evidence is discussed that indicates fishing mortality and continental climate change appear to have had lesser impacts. Similar starvation-advection explanations for declines in Japanese eel recruitment are proposed. Predictions for the future are made and multidisciplinary and integrated monitoring and research are recommended for managing eel stocks and fisheries.

  20. Long-term changes in the surface conditions of PLT

    International Nuclear Information System (INIS)

    Cohen, S.A.; Dylla, H.F.; Rossnagel, S.M.; Picraux, S.T.; Borders, J.A.; Magee, C.W.

    1977-01-01

    Long-term changes in the surface conditions of the PLT vacuum vessel wall have been monitored by the periodic analysis of a variety of sample substrates (stainless steel, alumina, silicon), exposed to PLT discharges for periods of up to several months and subsequently removed for analysis by Auger electron spectroscopy (AES), photoelectron spectroscopy, ion backscattering, nuclear reaction analysis, secondary ion mass spectroscopy, and scanning electron microscopy

  1. Long-term fundus changes in acquired partial lipodystrophy.

    Science.gov (United States)

    Jansen, Joyce; Delaere, Lien; Spielberg, Leigh; Leys, Anita

    2013-11-18

    We describe long-term fundus changes in a patient with partial lipodystrophy (PL). Retinal pigment alterations, drusen and subretinal neovascularisation were seen without evidence for membranoproliferative glomerulonephritis. Fundus alterations similar to those seen in age-related macular degeneration can occur at an earlier age in patients with PL, even without renal disease. Dysregulation of an alternative complement pathway with low serum levels of C3 has been implicated as a pathogenetic mechanism.

  2. Reconciling change blindness with long-term memory for objects.

    Science.gov (United States)

    Wood, Katherine; Simons, Daniel J

    2017-02-01

    How can we reconcile remarkably precise long-term memory for thousands of images with failures to detect changes to similar images? We explored whether people can use detailed, long-term memory to improve change detection performance. Subjects studied a set of images of objects and then performed recognition and change detection tasks with those images. Recognition memory performance exceeded change detection performance, even when a single familiar object in the postchange display consistently indicated the change location. In fact, participants were no better when a familiar object predicted the change location than when the displays consisted of unfamiliar objects. When given an explicit strategy to search for a familiar object as a way to improve performance on the change detection task, they performed no better than in a 6-alternative recognition memory task. Subjects only benefited from the presence of familiar objects in the change detection task when they had more time to view the prechange array before it switched. Once the cost to using the change detection information decreased, subjects made use of it in conjunction with memory to boost performance on the familiar-item change detection task. This suggests that even useful information will go unused if it is sufficiently difficult to extract.

  3. Common garden comparison of the leaf-out phenology of woody species from different native climates, combined with herbarium records, forecasts long-term change.

    Science.gov (United States)

    Zohner, Constantin M; Renner, Susanne S

    2014-08-01

    A well-timed phenology is essential for plant growth and reproduction, but species-specific phenological strategies are still poorly understood. Here, we use a common garden approach to compare biannual leaf-out data for 495 woody species growing outdoors in Munich, 90% of them not native to that climate regime. For three species, data were augmented by herbarium dates for 140-year-long time series. We further meta-analysed 107 temperate-zone woody species in which leaf-out cues have been studied, half of them also monitored here. Southern climate-adapted species flushed significantly later than natives, and photoperiod- and chilling- sensitive species all flushed late. The herbarium method revealed the extent of species-specific climate tracking. Our results forecast that: (1) a northward expansion of southern species due to climate warming will increase the number of late flushers in the north, counteracting documented and expected flushing time advances; and (2) photoperiod- and chilling-sensitive woody species cannot rapidly track climate warming. © 2014 John Wiley & Sons Ltd/CNRS.

  4. Hotter and drier conditions in the near future (2010-2035) might paradoxically improve the general adaptive capacity of a viticultural social-ecological system in Roussillon, southern France, exposed to long-term climatic and economic changes

    Science.gov (United States)

    Lereboullet, Anne-Laure; Beltrando, Gérard

    2014-05-01

    Background: Wine production in Roussillon, southern France, has been subjected to deep structural changes in cultural practices since the 1970's, due to changes in demand and market organization. In this Mediterranean region, temperature and rainfall parameters have long been adapted to fortified wine production, but might be less suited to dry wine production, which is nowadays prevailing. The wine industry in Roussillon can be studied as a social-ecological system where local economical and social characteristics are strongly linked to physical inputs. Thus changes in climate, especially warming and drying trends that have been detected and projected by the IPCC in the Mediterranean basin, may disrupt the local economy and social organization in the long term. The aim of our study is to assess the role played by recent (1956-2010) and near-future (2010-2035) changes in temperature and rainfall inputs in the evolution of the system's adaptive capacity to combined long term climatic and economic changes. Methods: Our study combined quantitative and qualitative data. We first assessed recent exposure to climate change by analysing change in daily data of temperature and rainfall observed in Perpignan weather station from 1956 to 2010. Thirty-nine in-depth interviews with local producers and key stakeholders of the local wine industry helped us understand the impacts of recent climatic conditions in the system's adaptive capacity. Then, we measured future changes in temperature and rainfall based on daily data simulated by ARPEGE-Climat (SCRATCH10 dataset) at an 8-km spatial scale, for emission scenarios A2, A1B and B1, up to 2060. Based on the impacts of recent changes in the system, we inferred the possible impacts of future climate change on the system's equilibrium. Results and discussion: Climate data analyses show that changes in temperatures and rainfall patterns have occurred in Perpignan since the mid-1980's, and that current (2001-2010) conditions are

  5. Long-term impact of changing childhood malnutrition on rotavirus diarrhoea: Two decades of adjusted association with climate and socio-demographic factors from urban Bangladesh.

    Science.gov (United States)

    Das, Sumon Kumar; Chisti, Mohammod Jobayer; Sarker, Mohammad Habibur Rahman; Das, Jui; Ahmed, Shawnawaz; Shahunja, K M; Nahar, Shamsun; Gibbons, Nora; Ahmed, Tahmeed; Faruque, Abu Syed Golam; Rahman, Mustafizur; J Fuchs, George; Al Mamun, Abdullah; John Baker, Peter

    2017-01-01

    There is strong association between childhood rotavirus, diarrhoea, climate factors and malnutrition. Conversely, a significant nutritional transition (reduced under-nutrition) with a concurrent increasing trend of rotavirus infection in last decade was also observed among under 5 children, especially in developing countries including Bangladesh. Considering the pathophysiology of rotavirus, there might be an interaction of this nutrition transition which plays a pivotal role in increasing rotavirus infection in addition to climate and other man-made factors in urban areas such as Dhaka, Bangladesh. Relevant monthly data from 1993-2012 were extracted from the archive of the Diarrhoeal Disease Surveillance System of icddr, b and linked with data collected from the Dhaka station of the Bangladesh Meteorological Department (mean temperature, rainfall, sea level pressure and humidity). Seasonal autoregressive integrated moving average time series models were deployed to determine the association between the monthly proportion of rotavirus infection and underweight, stunting and wasting adjusting for climate, socio-demographic and sanitation factors. The proportion of rotavirus cases among all causes diarrhoea increased from 20% in 1993 to 43% in 2012 (Chi squared for trend p = 0.010). In contrast, underweight, stunting and wasting decreased from 59%-29% (pchildhood malnutrition is significantly associated with increasing rotavirus diarrhoea among under-5 children. Thus mass vaccination in addition to interventions directed at man-made modifiable predictors for prevention and control is warranted.

  6. 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

    ) A1B emission scenario for the 21st century using three process-based models; A 20-year set (1991–2010) of observed daily climate data from Aarslev, Denmark was used to form the baseline, from which the RCM data were generated. The simulation of crop growth was performed with increasing carbon...... dioxide (CO2) levels and under continuous mono-cropping system at different N input rates. Results indicated that grain yield and grain N will be reduced in the future despite increased CO2 concentration in the atmosphere. While the increased N input may increase yield, it will not increase grain N...

  7. Melting of major Glaciers in the western Himalayas: evidence of climatic changes from long term MSU derived tropospheric temperature trend (1979–2008

    Directory of Open Access Journals (Sweden)

    A. K. Prasad

    2009-12-01

    Full Text Available Global warming or the increase of the surface and atmospheric temperatures of the Earth, is increasingly discernible in the polar, sub-polar and major land glacial areas. The Himalayan and Tibetan Plateau Glaciers, which are the largest glaciers outside of the Polar Regions, are showing a large-scale decrease of snow cover and an extensive glacial retreat. These glaciers such as Siachen and Gangotri are a major water resource for Asia as they feed major rivers such as the Indus, Ganga and Brahmaputra. Due to scarcity of ground measuring stations, the long-term observations of atmospheric temperatures acquired from the Microwave Sounding Unit (MSU since 1979–2008 is highly useful. The lower and middle tropospheric temperature trend based on 30 years of MSU data shows warming of the Northern Hemisphere's mid-latitude regions. The mean month-to-month warming (up to 0.048±0.026°K/year or 1.44°K over 30 years of the mid troposphere (near surface over the high altitude Himalayas and Tibetan Plateau is prominent and statistically significant at a 95% confidence interval. Though the mean annual warming trend over the Himalayas (0.016±0.005°K/year, and Tibetan Plateau (0.008±0.006°K/year is positive, the month to month warming trend is higher (by 2–3 times, positive and significant only over a period of six months (December to May. The factors responsible for the reversal of this trend from June to November are discussed here. The inequality in the magnitude of the warming trends of the troposphere between the western and eastern Himalayas and the IG (Indo-Gangetic plains is attributed to the differences in increased aerosol loading (due to dust storms over these regions. The monthly mean lower-tropospheric MSU-derived temperature trend over the IG plains (dust sink region; up to 0.032±0.027°K/year and dust source regions (Sahara desert, Middle East, Arabian region, Afghanistan-Iran-Pakistan and Thar Desert regions; up to 0.068±0.033

  8. Spatial and temporal distribution of long term public policy costs under uncertainty, the case of climate change; Distribution spatiale et temporelle des couts de politiques publiques sous incertitudes: theorie et pratique dans le cas de l'effet de serre

    Energy Technology Data Exchange (ETDEWEB)

    Lecocq, F

    2000-07-15

    Because of the inertia of the climate system, policy makers cannot avoid making early decisions regarding climate change in a sea of uncertainties. In this context, the very legitimacy of economic analysis to tackle such questions, and in particular the underlying equity issues (who pays for climate mitigation? when?) faces widespread skepticism. This thesis aims at demonstrating how public economy still remains a powerful tool to try and put some rationale into the debate, by checking the internal consistency of the different discourses, and by providing robust insights, if not definitive answers, into climate decisions. We use a set of compact integrated climate policy optimization models to progressively introduce, articulate, and assess numerically the prominent issues at stake. We obtain three main results. We first demonstrate that the so-called timing debate between short term and long term action cannot be reduced to a mere dispute over discount rate. Given the high uncertainties surrounding climate change indeed, the margins of freedom we pass on to future generations, and in particular the technical and institutional systems we transmit, become more important than the discount rate value. Secondly, we apply the various emission quota allocation rules proposed in the literature for the enlargement of annex B to developing economies. We show that the distributive outcome of these rules depends critically on ex ante assumptions about future economic and emission growth. Therefrom, we conclude that a careful design of the institutions surrounding the tradable permits market is a necessary condition to enhance the systems robustness. Last, on a broader perspective, this thesis illustrates the complementarity between ethics and economics: though the economist does not have per se a superior word about what is fair, his toolbox is powerful enough to show how some intuitively appealing ideas, such as a zero discount rate to take care of both present and future

  9. Long-term impact of changing childhood malnutrition on rotavirus diarrhoea: Two decades of adjusted association with climate and socio-demographic factors from urban Bangladesh.

    Directory of Open Access Journals (Sweden)

    Sumon Kumar Das

    Full Text Available There is strong association between childhood rotavirus, diarrhoea, climate factors and malnutrition. Conversely, a significant nutritional transition (reduced under-nutrition with a concurrent increasing trend of rotavirus infection in last decade was also observed among under 5 children, especially in developing countries including Bangladesh. Considering the pathophysiology of rotavirus, there might be an interaction of this nutrition transition which plays a pivotal role in increasing rotavirus infection in addition to climate and other man-made factors in urban areas such as Dhaka, Bangladesh.Relevant monthly data from 1993-2012 were extracted from the archive of the Diarrhoeal Disease Surveillance System of icddr, b and linked with data collected from the Dhaka station of the Bangladesh Meteorological Department (mean temperature, rainfall, sea level pressure and humidity. Seasonal autoregressive integrated moving average time series models were deployed to determine the association between the monthly proportion of rotavirus infection and underweight, stunting and wasting adjusting for climate, socio-demographic and sanitation factors.The proportion of rotavirus cases among all causes diarrhoea increased from 20% in 1993 to 43% in 2012 (Chi squared for trend p = 0.010. In contrast, underweight, stunting and wasting decreased from 59%-29% (p<0.001; 53%-21% (p<0.001 and 32%-22% (p<0.001 respectively over the same period. Mean ambient temperature increased from 25.76°C-26.62°C (p = 0.07; mean rainfall, sea level pressure and mean humidity decreased from 234.92-111.75 mm (p = 0.5, 1008.30-1006.61 mm of hg (p = 0.02 and 76.63%-70.26% (p<0.001, respectively. In the adjusted model, a decrease in monthly proportion of underweight [coef.: -0.189 (95% CI:-0.376, -0.003] and wasting [-0.265 (-0.455, -0.075] were significantly and inversely associated with rotavirus infection. However, an inverse but insignificant association was observed for

  10. Long-term agricultural experiments inform the development of climate-smart agricultural practices

    Directory of Open Access Journals (Sweden)

    Kristina Wolf

    2017-09-01

    Full Text Available California's Mediterranean agro-ecosystems are a major source of U.S. fruits and vegetables, and vulnerable to future extremes of precipitation and temperature brought on by climate change, including increased drought and flooding, and more intense and longer heat waves. To develop resilience to these threats, strategies are necessary for climate-smart management of soil and water. Long-term, large-scale, replicated ecological experiments provide unique testbeds for studying such questions. At the UC Davis Russell Ranch Sustainable Agriculture Facility (RRSAF, the 100-year Century Experiment, initiated in 1992, is investigating the effects of multiple farming practices in a farm-scale replicated study of 10 row crop cropping systems. It includes different fertility management systems: organic, conventional and hybrid (conventional plus winter cover crop systems; different crops: wheat, tomatoes, corn, alfalfa, cover crops and grasslands; and different irrigation systems: rainfed, flood irrigated and drip irrigated. We briefly describe and report on a selection of long-term experiments conducted at RRSAF investigating soil management and irrigation practices, which are an important focus for developing climate-smart strategies in Mediterranean systems. For example, long-term monitoring of soil carbon content revealed that most crop systems have experienced a small increase in soil carbon since 1993, and increases in organically managed plots were substantially higher. As RRSAF continues to build upon this rich dataset from one of a very few long-term row crop experiments in Mediterranean ecosystems, it provides a testbed for identifying climate-smart solutions for these agronomically important ecosystems.

  11. Impact of climate change and man-made irrigation systems on the transmission risk, long-term trend and seasonality of human and animal fascioliasis in Pakistan

    Directory of Open Access Journals (Sweden)

    Kiran Afshan

    2014-05-01

    Full Text Available Large areas of the province of Punjab, Pakistan are endemic for fascioliasis, resulting in high economic losses due to livestock infection but also affecting humans directly. The prevalence in livestock varies pronouncedly in space and time (1-70%. Climatic factors influencing fascioliasis presence and potential spread were analysed based on data from five mete- orological stations during 1990-2010. Variables such as wet days (Mt, water-budget-based system (Wb-bs indices and the normalized difference vegetation index (NDVI, were obtained and correlated with geographical distribution, seasonality patterns and the two-decade evolution of fascioliasis in livestock throughout the province. The combined approach by these three indices proved to furnish a useful tool to analyse the complex epidemiology that includes (i sheep-goats and cattle- buffaloes presenting different immunological responses to fasciolids; (ii overlap of Fasciola hepatica and F. gigantica; (iii co-existence of highlands and lowlands in the area studied; and (iv disease transmission following bi-seasonality with one peak related to natural rainfall and another peak related to man-made irrigation. Results suggest a human infection situa- tion of concern and illustrate how climate and anthropogenic environment modifications influence both geographical dis- tribution and seasonality of fascioliasis risks. Increased fascioliasis risk throughout the Punjab plain and its decrease in the northern highlands of the province became evident during the study period. The high risk in the lowlands is worrying given that Punjab province largely consists of low-altitude, highly irrigated plains. The importance of livestock in this province makes it essential to prioritise adequate control measures. An annual treatment scheme to control the disease is recom- mended to be applied throughout the whole province.

  12. Impact of climate change and man-made irrigation systems on the transmission risk, long-term trend and seasonality of human and animal fascioliasis in Pakistan.

    Science.gov (United States)

    Afshan, Kiran; Fortes-Lima, Cesar A; Artigas, Patricio; Valero, Adela M; Qayyum, Mazhar; Mas-Coma, Santiago

    2014-05-01

    Large areas of the province of Punjab, Pakistan are endemic for fascioliasis, resulting in high economic losses due to livestock infection but also affecting humans directly. The prevalence in livestock varies pronouncedly in space and time (1-70%). Climatic factors influencing fascioliasis presence and potential spread were analysed based on data from five meteorological stations during 1990-2010. Variables such as wet days (Mt), water-budget-based system (Wb-bs) indices and the normalized difference vegetation index (NDVI), were obtained and correlated with geographical distribution, seasonality patterns and the two-decade evolution of fascioliasis in livestock throughout the province. The combined approach by these three indices proved to furnish a useful tool to analyse the complex epidemiology that includes (i) sheep-goats and cattlebuffaloes presenting different immunological responses to fasciolids; (ii) overlap of Fasciola hepatica and F. gigantica; (iii) co-existence of highlands and lowlands in the area studied; and (iv) disease transmission following bi-seasonality with one peak related to natural rainfall and another peak related to man-made irrigation. Results suggest a human infection situation of concern and illustrate how climate and anthropogenic environment modifications influence both geographical distribution and seasonality of fascioliasis risks. Increased fascioliasis risk throughout the Punjab plain and its decrease in the northern highlands of the province became evident during the study period. The high risk in the lowlands is worrying given that Punjab province largely consists of low-altitude, highly irrigated plains. The importance of livestock in this province makes it essential to prioritise adequate control measures. An annual treatment scheme to control the disease is recommended to be applied throughout the whole province.

  13. Long-term tree growth rate, water use efficiency, and tree ring nitrogen isotope composition of Pinus massoniana L. in response to global climate change and local nitrogen deposition in Southern China

    Energy Technology Data Exchange (ETDEWEB)

    Sun, Fangfang [Chinese Academy of Sciences, Guangzhou (China). South China Botanical Garden; Graduate Univ. of Chinese Academy of Sciences, Beijing (China); Griffith Univ., Nathan, QLD (Australia). Environmental Future Centre; Kuang, Yuanwen; Wen, Dazhi [Chinese Academy of Sciences, Guangzhou (China). South China Botanical Garden; Chinese Academy of Sciences, Guangzhou (China). Pearl River Delta Research Centre of Environmental Pollution and Control; Xu, Zhihong [Griffith Univ., Nathan, QLD (Australia). Environmental Future Centre; Li, Jianli; Zuo, Weidong [Agriculture and Forestry Technology Extension Centre, Nanhai District, Guangdong (China); Hou, Enqing [Chinese Academy of Sciences, Guangzhou (China). South China Botanical Garden; Graduate Univ. of Chinese Academy of Sciences, Beijing (China)

    2010-12-15

    We aimed to investigate long-term tree growth rates, water use efficiencies (WUE), and tree ring nitrogen (N) isotope compositions ({delta}{sup 15}N) of Masson pine (Pinus massoniana L.) in response to global climate change and local N deposition in Southern China. Tree annual growth rings of Masson pine were collected from four forest sites, viz. South China Botanical Garden (SBG), Xi Qiao Shan (XQS) Forest Park, Ding Hu Shan (DHS) Natural Reserve, and Nan Kun Shan (NKS) Natural Reserve in Southern China. The mean annual basal area increment (BAI), WUE, and {delta}{sup 15}N at every 5-year intervals of Masson pine during the last 50 years were determined. Regression analyses were used to quantify the relationships of BAI and WUE with atmospheric carbon dioxide concentration ([CO{sub 2}]), temperature, rainfall, and tree ring elemental concentrations at the four study sites. Tree BAI showed a quadratic relationship with rising [CO{sub 2}]. The tipping points of [CO{sub 2}] for BAI, the peaks of BAI when the critical [CO{sub 2}] was reached, occurred earlier at the sites of SBG, XQS, and DHS which were exposed to higher temperature, N deposition, and lower mineral nutrient availability, as compared with the tipping points of [CO{sub 2}] for BAI at the site of NKS which had higher rainfall, lower temperature, and better nutritional status. The average tipping point of [CO{sub 2}] at the four sites for the BAI response curves was 356 ppm, after which, the BAI would be expected to decrease quadratically with rising [CO{sub 2}]. The multiple regressions of BAI confirmed the relationships of long-term tree growth rate with rainfall, tree WUE, and nutrients and {delta}{sup 15}N in tree rings. Nonlinear relationships between BAI and tree ring {delta}{sup 15}N at DHS and negatively linear one at NKS reflected the fertilization effect of N deposition on tree growth rate initially, but this effect peaked or became negative once the forest approached or passed the N saturation

  14. Changes in the properties of superalloys by long term heating

    International Nuclear Information System (INIS)

    Susukida, H.; Tsuji, I.; Kawai, H.

    1976-01-01

    A laboratory study was conducted in order to determine the effect of long term heating (max. 10000h at 850 0 and 950 0 C) on the microstructure, tensile properties, hardness and stress rupture properties of four kinds of superalloys. These superalloys are two kinds of solid solution hardened Ni-base superalloys Hastelloy X and Inconel 617 and two kinds of dispersion strengthened Ni-base superalloys TD-Ni and TD-NiCr. The result of the study can be summarized as follows: (1) Solid solution hardened superalloys: Many precipitates were observed in the grains and on the grain boundaries after 100 hours of heating, and the precipitates became coarse-grained by over 1000 hours of heating. This tendency was remarkable when they were heated at 950 0 C. With the change of their microstructure, their mechanical properties also changed, particularly their tensile ductility decreased remarkably. (2) Dispersion strengthened superalloys: Their microstructure and mechanical properties were almost unchanged by long term heating. (3) The authors proposed ''solid solution hardening value'' in order to grasp quantitatively the solid solution hardening which has been discussed by the content of each element hitherto. (auth.)

  15. Implementing culture change in long-term dementia care settings.

    Science.gov (United States)

    McGreevy, Jessica

    2016-01-06

    The approach to nursing in long-term care settings for people living with dementia continues to evolve from a traditional, task-oriented culture to one that is person-centred. Such change can be difficult to manage and may encounter considerable opposition; having an understanding of change management and leadership styles may help to make this transition easier. This article discusses the differences between task-oriented and person-centred care, theories of management, motivation and leadership styles, and focuses on those that are most appropriate for this type of change. An improved understanding of these theories will enable nurses to support others in the delivery of person-centred care.

  16. Changes of the eye during long-term spaceflight. Review

    Directory of Open Access Journals (Sweden)

    I. A. Makarov

    2016-01-01

    Full Text Available The review includes the publications of the scientific literature on the eye change during long-term spaceflight. The any eye changes such as visual impairment, hyperopic shift in refraction, changes in the intraocular pressure, increased the intracranial pressure, globe flattening, choroidal folding, optic disc edema, and optic nerve kinking and other changes were reported. The main cause of eye disorders, in all probability, is the increase of the intracranial pressure during long-term spaceflight. The reasons of the increased intracranial pressure are a collection of various factors of adaptation mechanisms in the body to weightless conditions. The leading role in the development of intracranial hypertension takes a redistribution of the body fluids (blood and lymph in the direction of the head, but the opportunities and the effect of other factors are present. Also the displacement and increase of the internal organs volume of the chest can cause external compression of the jugular veins, increasing the pressure of the blood in them, and as the result to lead to the increase of the intracranial pressure. The role of trigger such mechanisms in the development of the intracranial hypertension in the microgravity environment as anatomical predisposition of the body, race, metabolic changes under the influence of high carbon dioxide content in the different compartments of the station, high sodium intake, the enzyme dysfunction, weight exercises of the astronauts was discussed. However, the pathogenic mechanisms is currently still under investigation. An important role in the study of the adaptation mechanisms is given to research not only before and after the flight, but also during the space flight. The accumulated knowledge and experience about the changes in organs and systems in the conditions of human adaptation to microgravity will help answer many questions related to the implementation of the long spaceflights.

  17. Long Term Storage of cytogenetic changes in liquidators of Chernobyl

    International Nuclear Information System (INIS)

    Karpov, V. B.

    2004-01-01

    At present chromosome aberration analysis in lymphocytes as well as micronucleus assay are most reliable methods of bio indication of radiation effects. The problem of persistent of cytogenetic changes during the long term after exposure is very important. The cytogenetic studies of liquidators residents of St. Petersburg and region revealed that the average chromosome aberration rate 4-5 years after the accident constitutes 4.94±0.38, number of aberrant cells was 4.82±0.36, dicentrics -0.23±0.10 per 100 cells, micronucleus number -46.1±2.1 per 100 cells that is significantly higher than in control group. dispersion analysis confirms the reported level of external exposure effects on chromosome aberration rate (?=0.04) in this group of liquidators. In 73 persons from the group of high risk participants of nuclear tests, nuclear submarine personnel 8-45 years after average number of chromosome aberrations was 6.5±0.32; dicentrics - 0.64±0.10, centric rings- 0.04±0.02 per 100 cells, for micronuclei -51.4±2.82 per thousand cells, that is significantly higher than in control group (p<0.01). In 45.2% cases the aberration markers (disentrics and centric rings) were found. The late cytogenetic effects were observed after decades and possibility to use these indicators for long term diagnosis is now under consideration. (Author)

  18. The regional climate model as a tool for long-term planning of Quebec water resources

    International Nuclear Information System (INIS)

    Frigon, A.

    2008-01-01

    'Full text': In recent years, important progress has been made in downscaling GCM (Global Climate Model) projections to a resolution where hydrological studies become feasible. Climate change simulations performed with RCMs (Regional Climate Models) have reached a level of confidence that allows us to take advantage of this information in long-term planning of water resources. The RCMs' main advantage consist in their construction based on balanced land as well as atmosphere water and energy budgets, and on their inclusion of feedbacks between the surface and the atmosphere. Such models therefore generate sequences of weather events, providing long time series of hydro-climatic variables that are internally consistent, allowing the analysis of hydrologic regimes. At OURANOS, special attention is placed on the hydrological cycle, given its key role on socioeconomic activities. The Canadian Regional Climate Model (CRCM) was developed as a potential tool to provide climate projections at the watershed scale. Various analyses performed over small basins in Quebec provide information on the level of confidence we have in the CRCM for use in hydrological studies. Even though this approach is not free of uncertainty, it was found useful by some water resource managers and hence this information should be considered. One of the keys to retain usefulness, despite the associated uncertainties, is to make use of more than a single regional climate projection. This approach will allow for the evaluation of the climate change signal and its associated level of confidence. Such a methodology is already applied by Hydro-Quebec in the long-term planning of its water resources for hydroelectric generation over the Quebec territory. (author)

  19. Strategies for the long-term climate policy. The results of the Cool project. Final report of the second phase of the Dutch National Research Programme on Global Air Pollution and Climate Change (NRP II) 1995-2001. Part 2

    NARCIS (Netherlands)

    Berk M; Hisschemoller M; Mol T; Hordijk L; Kok M; Metz B; NOP

    2002-01-01

    This report, Climate Change, a Permanent Concern, presents the results of research that was conducted in over 90 projects during the second phase of the National Research Programme on Global Air Pollution and Climate Change (NRP-II, 1995-2001). The report is intended for policymakers, members of

  20. Long-term trends in geomagnetic and climatic variability

    Czech Academy of Sciences Publication Activity Database

    Bucha, Václav

    2002-01-01

    Roč. 27, 6/7 (2002), s. 427-731 ISSN 1474-7065 R&D Projects: GA AV ČR IAA3012806 Institutional research plan: CEZ:AV0Z3012916 Keywords : geomagnetic forcing * climatic variability * global warming Subject RIV: DE - Earth Magnetism, Geodesy, Geography

  1. Modified climate with long term memory in tree ring proxies

    Czech Academy of Sciences Publication Activity Database

    Zhang, H.; Yuan, N.; Esper, J.; Werner, J. P.; Xoplaki, E.; Büntgen, Ulf; Treydte, K.; Luterbacher, J.

    2015-01-01

    Roč. 10, č. 8 (2015), č. článku 084020. ISSN 1748-9326 Institutional support: RVO:67179843 Keywords : surface-temperature * northern-hemisphere * china * variability * persistence * precipitation * fluctuations * millennium * rainfall * model * climate reconstructions * tree-ring width * maximum latewood density * frequency domains Subject RIV: EH - Ecology, Behaviour Impact factor: 4.134, year: 2015

  2. Long-term climate policy implications of phasing out fossil fuel subsidies

    International Nuclear Information System (INIS)

    Schwanitz, Valeria Jana; Piontek, Franziska; Bertram, Christoph; Luderer, Gunnar

    2014-01-01

    It is often argued that fossil fuel subsidies hamper the transition towards a sustainable energy supply as they incentivize wasteful consumption. We assess implications of a subsidy phase-out for the mitigation of climate change and the low-carbon transformation of the energy system, using the global energy–economy model REMIND. We compare our results with those obtained by the International Energy Agency (based on the World Energy Model) and by the Organization for Economic Co-Operation and Development (OECD-Model ENV-Linkages), providing the long-term perspective of an intertemporal optimization model. The results are analyzed in the two dimensions of subsidy phase-out and climate policy scenarios. We confirm short-term benefits of phasing-out fossil fuel subsidies as found in prior studies. However, these benefits are only sustained to a small extent in the long term, if dedicated climate policies are weak or nonexistent. Most remarkably we find that a removal of fossil fuel subsidies, if not complemented by other policies, can slow down a global transition towards a renewable based energy system. The reason is that world market prices for fossil fuels may drop due to a removal of subsidies. Thus, low carbon alternatives would encounter comparative disadvantages. - Highlights: • We assess implications of phasing out fossil fuel subsidies on the mitigation of climate change. • The removal of subsidies leads to a net-reduction in the use of energy. • Emission reductions contribute little to stabilize greenhouse gases at 450 ppm if not combined with climate policies. • Low carbon alternatives may encounter comparative disadvantages due to relative price changes at world markets

  3. High estimates of supply constrained emissions scenarios for long-term climate risk assessment

    International Nuclear Information System (INIS)

    Ward, James D.; Mohr, Steve H.; Myers, Baden R.; Nel, Willem P.

    2012-01-01

    The simulated effects of anthropogenic global warming have become important in many fields and most models agree that significant impacts are becoming unavoidable in the face of slow action. Improvements to model accuracy rely primarily on the refinement of parameter sensitivities and on plausible future carbon emissions trajectories. Carbon emissions are the leading cause of global warming, yet current considerations of future emissions do not consider structural limits to fossil fuel supply, invoking a wide range of uncertainty. Moreover, outdated assumptions regarding the future abundance of fossil energy could contribute to misleading projections of both economic growth and climate change vulnerability. Here we present an easily replicable mathematical model that considers fundamental supply-side constraints and demonstrate its use in a stochastic analysis to produce a theoretical upper limit to future emissions. The results show a significant reduction in prior uncertainty around projected long term emissions, and even assuming high estimates of all fossil fuel resources and high growth of unconventional production, cumulative emissions tend to align to the current medium emissions scenarios in the second half of this century. This significant finding provides much-needed guidance on developing relevant emissions scenarios for long term climate change impact studies. - Highlights: ► GHG emissions from conventional and unconventional fossil fuels modelled nationally. ► Assuming worst-case: large resource, high growth, rapid uptake of unconventional. ► Long-term cumulative emissions align well with the SRES medium emissions scenario. ► High emissions are unlikely to be sustained through the second half of this century. ► Model designed to be easily extended to test other scenarios e.g. energy shortages.

  4. Long-term changes in sea surface temperatures

    International Nuclear Information System (INIS)

    Parker, D.E.

    1994-01-01

    Historical observations of sea surface temperature since 1856 have been improved by applying corrections to compensate for the predominant use of uninsulated or partly insulated buckets until the Second World War. There are large gaps in coverage in the late nineteenth century and around the two world wars, but a range of statistical techniques suggest that these gaps do not severely prejudice estimates of global and regional climatic change. Nonetheless, to improve the analysis on smaller scales, many unused historical data are to be digitized and incorporated. For recent years, satellite-based sea surface temperatures have improved the coverage, after adjustments for their biases relative to in situ data. An initial version of a nominally globally complete sea ice and interpolated sea surface temperature data set, beginning in 1871, has been created for use in numerical simulations of recent climate. Long time series of corrected regional, hemispheric, and global sea surface temperatures are mostly consistent with corresponding night marine air temperature series, and confirm the regionally specific climatic changes portrayed in the Scientific Assessments of the intergovernmental Panel on Climate Change. The observations also show an El Nino-like oscillation on bidecadal and longer time scales

  5. Long Term Population, City Size and Climate Trends in the Fertile Crescent: A First Approximation.

    Science.gov (United States)

    Lawrence, Dan; Philip, Graham; Hunt, Hannah; Snape-Kennedy, Lisa; Wilkinson, T J

    2016-01-01

    Over the last 8000 years the Fertile Crescent of the Near East has seen the emergence of urban agglomerations, small scale polities and large territorial empires, all of which had profound effects on settlement patterns. Computational approaches, including the use of remote sensing data, allow us to analyse these changes at unprecedented geographical and temporal scales. Here we employ these techniques to examine and compare long term trends in urbanisation, population and climate records. Maximum city size is used as a proxy for the intensity of urbanisation, whilst population trends are modelled from settlement densities in nine archaeological surveys conducted over the last 30 years across the region. These two measures are then compared with atmospheric moisture levels derived from multiple proxy analyses from two locations close to the study area, Soreq Cave in Israel and Lake Van in south-eastern Turkey, as well as wider literature. The earliest urban sites emerged during a period of relatively high atmospheric moisture levels and conform to a series of size thresholds. However, after the Early Bronze Age maximum urban size and population levels increase rapidly whilst atmospheric moisture declines. We argue that although the initial phase of urbanization may have been linked to climate conditions, we can see a definitive decoupling of climate and settlement patterns after 2000 BC. We relate this phenomenon to changes in socio-economic organisation and integration in large territorial empires. The complex relationships sustaining urban growth during this later period resulted in an increase in system fragility and ultimately impacted on the sustainability of cities in the long term.

  6. Climate change

    Science.gov (United States)

    Cronin, Thomas M.

    2016-01-01

    Climate change (including climate variability) refers to regional or global changes in mean climate state or in patterns of climate variability over decades to millions of years often identified using statistical methods and sometimes referred to as changes in long-term weather conditions (IPCC, 2012). Climate is influenced by changes in continent-ocean configurations due to plate tectonic processes, variations in Earth’s orbit, axial tilt and precession, atmospheric greenhouse gas (GHG) concentrations, solar variability, volcanism, internal variability resulting from interactions between the atmosphere, oceans and ice (glaciers, small ice caps, ice sheets, and sea ice), and anthropogenic activities such as greenhouse gas emissions and land use and their effects on carbon cycling.

  7. Climate effects and feedback structure determining weed population dynamics in a long-term experiment.

    Science.gov (United States)

    Lima, Mauricio; Navarrete, Luis; González-Andujar, José Luis

    2012-01-01

    Pest control is one of the areas in which population dynamic theory has been successfully applied to solve practical problems. However, the links between population dynamic theory and model construction have been less emphasized in the management and control of weed populations. Most management models of weed population dynamics have emphasized the role of the endogenous process, but the role of exogenous variables such as climate have been ignored in the study of weed populations and their management. Here, we use long-term data (22 years) on two annual weed species from a locality in Central Spain to determine the importance of endogenous and exogenous processes (local and large-scale climate factors). Our modeling study determined two different feedback structures and climate effects in the two weed species analyzed. While Descurainia sophia exhibited a second-order feedback and low climate influence, Veronica hederifolia was characterized by a first-order feedback structure and important effects from temperature and rainfall. Our results strongly suggest the importance of theoretical population dynamics in understanding plant population systems. Moreover, the use of this approach, discerning between the effect of exogenous and endogenous factors, can be fundamental to applying weed management practices in agricultural systems and to controlling invasive weedy species. This is a radical change from most approaches currently used to guide weed and invasive weedy species managements.

  8. Climate Effects and Feedback Structure Determining Weed Population Dynamics in a Long-Term Experiment

    Science.gov (United States)

    Lima, Mauricio; Navarrete, Luis; González-Andujar, José Luis

    2012-01-01

    Pest control is one of the areas in which population dynamic theory has been successfully applied to solve practical problems. However, the links between population dynamic theory and model construction have been less emphasized in the management and control of weed populations. Most management models of weed population dynamics have emphasized the role of the endogenous process, but the role of exogenous variables such as climate have been ignored in the study of weed populations and their management. Here, we use long-term data (22 years) on two annual weed species from a locality in Central Spain to determine the importance of endogenous and exogenous processes (local and large-scale climate factors). Our modeling study determined two different feedback structures and climate effects in the two weed species analyzed. While Descurainia sophia exhibited a second-order feedback and low climate influence, Veronica hederifolia was characterized by a first-order feedback structure and important effects from temperature and rainfall. Our results strongly suggest the importance of theoretical population dynamics in understanding plant population systems. Moreover, the use of this approach, discerning between the effect of exogenous and endogenous factors, can be fundamental to applying weed management practices in agricultural systems and to controlling invasive weedy species. This is a radical change from most approaches currently used to guide weed and invasive weedy species managements. PMID:22272362

  9. Climate effects and feedback structure determining weed population dynamics in a long-term experiment.

    Directory of Open Access Journals (Sweden)

    Mauricio Lima

    Full Text Available Pest control is one of the areas in which population dynamic theory has been successfully applied to solve practical problems. However, the links between population dynamic theory and model construction have been less emphasized in the management and control of weed populations. Most management models of weed population dynamics have emphasized the role of the endogenous process, but the role of exogenous variables such as climate have been ignored in the study of weed populations and their management. Here, we use long-term data (22 years on two annual weed species from a locality in Central Spain to determine the importance of endogenous and exogenous processes (local and large-scale climate factors. Our modeling study determined two different feedback structures and climate effects in the two weed species analyzed. While Descurainia sophia exhibited a second-order feedback and low climate influence, Veronica hederifolia was characterized by a first-order feedback structure and important effects from temperature and rainfall. Our results strongly suggest the importance of theoretical population dynamics in understanding plant population systems. Moreover, the use of this approach, discerning between the effect of exogenous and endogenous factors, can be fundamental to applying weed management practices in agricultural systems and to controlling invasive weedy species. This is a radical change from most approaches currently used to guide weed and invasive weedy species managements.

  10. Long-Term Variability of Surface Albedo and Its Correlation with Climatic Variables over Antarctica

    Directory of Open Access Journals (Sweden)

    Minji Seo

    2016-11-01

    Full Text Available The cryosphere is an essential part of the earth system for understanding climate change. Components of the cryosphere, such as ice sheets and sea ice, are generally decreasing over time. However, previous studies have indicated differing trends between the Antarctic and the Arctic. The South Pole also shows internal differences in trends. These phenomena indicate the importance of continuous observation of the Polar Regions. Albedo is a main indicator for analyzing Antarctic climate change and is an important variable with regard to the radiation budget because it can provide positive feedback on polar warming and is related to net radiation and atmospheric heating in the mainly snow- and ice-covered Antarctic. Therefore, in this study, we analyzed long-term temporal and spatial variability of albedo and investigated the interrelationships between albedo and climatic variables over Antarctica. We used broadband surface albedo data from the Satellite Application Facility on Climate Monitoring and data for several climatic variables such as temperature and Antarctic oscillation index (AAO during the period of 1983 to 2009. Time series analysis and correlation analysis were performed through linear regression using albedo and climatic variables. The results of this research indicated that albedo shows two trends, west trend and an east trend, over Antarctica. Most of the western side of Antarctica showed a negative trend of albedo (about −0.0007 to −0.0015 year−1, but the other side showed a positive trend (about 0.0006 year−1. In addition, albedo and surface temperature had a negative correlation, but this relationship was weaker in west Antarctica than in east Antarctica. The correlation between albedo and AAO revealed different relationships in the two regions; west Antarctica had a negative correlation and east Antarctica showed a positive correlation. In addition, the correlation between albedo and AAO was weaker in the west. This

  11. Long Term Large Scale river nutrient changes across the UK

    Science.gov (United States)

    Bell, Victoria; Naden, Pam; Tipping, Ed; Davies, Helen; Davies, Jessica; Dragosits, Ulli; Muhammed, Shibu; Quinton, John; Stuart, Marianne; Whitmore, Andy; Wu, Lianhai

    2017-04-01

    During recent decades and centuries, pools and fluxes of Carbon, Nitrogen and Phosphorus (C, N and P) in UK rivers and ecosystems have been transformed by the spread and fertiliser-based intensification of agriculture (necessary to sustain human populations), by atmospheric pollution, by human waste (rising in line with population growth), and now by climate change. The principal objective of the UK's NERC-funded Macronutrients LTLS research project has been to account for observable terrestrial and aquatic pools, concentrations and fluxes of C, N and P on the basis of past inputs, biotic and abiotic interactions, and transport processes. More specifically, over the last 200 years, what have been the temporal responses of plant and soil nutrient pools in different UK catchments to nutrient enrichment, and what have been the consequent effects on nutrient transfers from land to the atmosphere, freshwaters and estuaries? The work described here addresses the second question by providing an integrated quantitative description of the interlinked land and water pools and annual fluxes of C, N and P for UK catchments over time. A national-scale modelling environment has been developed, combining simple physically-based gridded models that can be parameterised using recent observations before application to long timescales. The LTLS Integrated Model (LTLS-IM) uses readily-available driving data (climate, land-use, nutrient inputs, topography), and model estimates of both terrestrial and freshwater nutrient loads have been compared with measurements from sites across the UK. Here, the focus is on the freshwater nutrient component of the LTLS-IM, but the terrestrial nutrient inputs required for this are provided by models of nutrient processes in semi-natural and agricultural systems, and from simple models of nutrients arising from human waste. In the freshwater model, lateral routing of dissolved and particulate nutrients and within-river processing such as

  12. Long-term sustainability of the landscape in new climatic conditions

    Science.gov (United States)

    Kubeckova, D.; Krocova, S.

    2017-10-01

    The long-term sustainability of the landscape and its natural environment must be the decisive task of the public administration and, in the wider concept, of every citizen. In new climatic conditions, this need has intensified. The following article suggests in a basic scope whether the above-mentioned task can be accomplished, and what means of solution should be used.

  13. Long-term visual changes following pituitary irradiation

    International Nuclear Information System (INIS)

    Movsas, Benjamin; Movsas, Tammy Z.; Steinberg, Seth M.; Okunieff, Paul

    1995-01-01

    Purpose: To analyze possible long-term effects of pituitary irradiation on visual fields and acuity. Methods and Materials: Eighty-six patients were treated with radiotherapy for pituitary tumors at the National Cancer Institute between 1980 and 1991. Twenty-one patients had baseline preradiation and long-term follow-up visual fields. Eyes were followed with serial Goldmann or Humphrey visual field testing. Neuroradiologic correlation was made with the available brain scans. There were 12 females and 9 males with an median age of 44. Eighteen patients had hormone-secreting tumors and three had chromophobe adenomas. All but one patient with an inoperable invasive macroadenoma were irradiated after one or more transphenoidal resections or a craniotomy. The indications for radiation in the operable patients were: nine patients, partial tumor resection; nine patients, tumor recurrence; and two patients, persistent hormonal elevation after surgery. The median dose delivered was 50 Gy (45-59.4 Gy). The average field size was 6 x 6 cm (5 x 5 cm to 10 x 12.5 cm). Results: With a median follow-up of 48 months (14-128) after radiotherapy, 1 out of 21 patients has recurred (at 8 months) and all patients are alive. Of the 38 sighted eyes, 27 had normal visual fields before and after radiation, 7 eyes showed improvement, and 4 eyes had a stable defect, mostly in the superior temporal region. There were no cases of radiation-induced visual field or acuity deterioration. Six out of 21 patients (29%) had neurologic symptoms in follow-up, most of which appeared vascular in nature. Four patients complained of atypical migranous-like headaches that first began 1.5-3 years following treatment. One patient complained of recurrent vertical diplopia and one patient had a cerebral vascular accident 7 years following therapy. A dose-related association with these neurovascular symptoms approached statistical significance. Only 1 out of 11 (9%) patients who received doses less than or equal

  14. Coping with climate variability and long-term climate trends for Nicaraguan maize-bean farmers (Invited)

    Science.gov (United States)

    Gourdji, S.; Zelaya Martinez, C.; Martinez Valle, A.; Mejia, O.; Laderach, P.; Lobell, D. B.

    2013-12-01

    Climate variability and change impact farmers at different timescales, but both are of concern for livelihoods and long-term viability of small farms in tropical, rain-fed agricultural systems. This study uses a historical dataset to analyze the impact of 40-year climate trends in Nicaragua on bean production, a staple crop that is an important source of calories and protein in the local diet, particularly in rural areas and in lower income classes. Bean yields are sensitive to rising temperatures, but also frequently limited by seasonal drought and low soil fertility. We use an empirical model to relate department-level yields to spatial variation and inter-annual fluctuations in historical precipitation, temperature and extreme rain events. We then use this model to quantify the impact on yields of long-term observed warming in day and night temperatures, increases in rainfall intensity, longer gaps between rain events, a shorter rainy season and overall drying in certain regions of the country. Preliminary results confirm the negative impacts of warming night temperatures, higher vapor pressure deficits, and longer gaps between rain events on bean yields, although some drying at harvest time has helped to reduce rotting. Across all bean-growing areas, these climate trends have led to a ~10% yield decline per decade relative to a stationary climate and production system, with this decline reaching up to ~20% in the dry northern highlands. In regions that have been particularly impacted by these trends, we look for evidence of farm abandonment, increases in off-farm employment, or on-farm adaptation solutions through crop diversification, use of drought or heat-tolerant seed, and adoption of rainwater harvesting. We will also repeat the modeling exercise for maize, another staple crop providing ~25% of daily calories at the national scale, but which is projected to be more resilient to climate trends.

  15. The role of tectonic uplift, climate, and vegetation in the long-term terrestrial phosphorous cycle

    Directory of Open Access Journals (Sweden)

    C. Buendía

    2010-06-01

    Full Text Available Phosphorus (P is a crucial element for life and therefore for maintaining ecosystem productivity. Its local availability to the terrestrial biosphere results from the interaction between climate, tectonic uplift, atmospheric transport, and biotic cycling. Here we present a mathematical model that describes the terrestrial P-cycle in a simple but comprehensive way. The resulting dynamical system can be solved analytically for steady-state conditions, allowing us to test the sensitivity of the P-availability to the key parameters and processes. Given constant inputs, we find that humid ecosystems exhibit lower P availability due to higher runoff and losses, and that tectonic uplift is a fundamental constraint. In particular, we find that in humid ecosystems the biotic cycling seem essential to maintain long-term P-availability. The time-dependent P dynamics for the Franz Josef and Hawaii chronosequences show how tectonic uplift is an important constraint on ecosystem productivity, while hydroclimatic conditions control the P-losses and speed towards steady-state. The model also helps describe how, with limited uplift and atmospheric input, as in the case of the Amazon Basin, ecosystems must rely on mechanisms that enhance P-availability and retention. Our novel model has a limited number of parameters and can be easily integrated into global climate models to provide a representation of the response of the terrestrial biosphere to global change.

  16. The effect of long-term changes in plant inputs on soil carbon stocks

    Science.gov (United States)

    Georgiou, K.; Li, Z.; Torn, M. S.

    2017-12-01

    Soil organic carbon (SOC) is the largest actively-cycling terrestrial reservoir of C and an integral component of thriving natural and managed ecosystems. C input interventions (e.g., litter removal or organic amendments) are common in managed landscapes and present an important decision for maintaining healthy soils in sustainable agriculture and forestry. Furthermore, climate and land-cover change can also affect the amount of plant C inputs that enter the soil through changes in plant productivity, allocation, and rooting depth. Yet, the processes that dictate the response of SOC to such changes in C inputs are poorly understood and inadequately represented in predictive models. Long-term litter manipulations are an invaluable resource for exploring key controls of SOC storage and validating model representations. Here we explore the response of SOC to long-term changes in plant C inputs across a range of biomes and soil types. We synthesize and analyze data from long-term litter manipulation field experiments, and focus our meta-analysis on changes to total SOC stocks, microbial biomass carbon, and mineral-associated (`protected') carbon pools and explore the relative contribution of above- versus below-ground C inputs. Our cross-site data comparison reveals that divergent SOC responses are observed between forest sites, particularly for treatments that increase C inputs to the soil. We explore trends among key variables (e.g., microbial biomass to SOC ratios) that inform soil C model representations. The assembled dataset is an important benchmark for evaluating process-based hypotheses and validating divergent model formulations.

  17. What are driving the long-term Caspian Sea level change?

    Science.gov (United States)

    Chen, J.

    2017-12-01

    Caspian Sea level (CSL) has undergone substantial fluctuations during the past several hundred years. The causes over the entire historical period are uncertain, but we investigate here large changes seen in the past several decades. We use climate model predicted precipitation (P), evaporation (E), and observed river runoff (R) to reconstruct long-term CSL changes for 1979-2015, and show that PER (P-E+R) flux predictions agree very well with observed CSL changes. The observed rapid CSL increase (about 12.74 cm/yr) and significant drop ( -6.72 cm/yr) during the periods 1979-1995 and 1996-2015 are well accounted for by integrated PER flux predictions of +12.38 and -6.79 cm/yr, respectively. We show that increased evaporation rates over the Caspian Sea play a dominant role in reversing the increasing trend in CSL during the past 37 years. The current long-term decline in CSL is expected to continue into the foreseeable future, under global warming scenarios.

  18. Long-term changes and trends in the upper atmosphere - An introduction

    Czech Academy of Sciences Publication Activity Database

    Laštovička, Jan; Akmaev, R. A.; Emmert, J. T.

    2009-01-01

    Roč. 71, 14-15 (2009), s. 1511-1513 ISSN 1364-6826 Institutional research plan: CEZ:AV0Z30420517 Keywords : long-term changes * long-term trends * upper atmosphere Subject RIV: DG - Athmosphere Sciences, Meteorology Impact factor: 1.643, year: 2009 http://www.sciencedirect.com/science/journal/13646826

  19. Long-term memory and volatility clustering in high-frequency price changes

    Science.gov (United States)

    oh, Gabjin; Kim, Seunghwan; Eom, Cheoljun

    2008-02-01

    We studied the long-term memory in diverse stock market indices and foreign exchange rates using Detrended Fluctuation Analysis (DFA). For all high-frequency market data studied, no significant long-term memory property was detected in the return series, while a strong long-term memory property was found in the volatility time series. The possible causes of the long-term memory property were investigated using the return data filtered by the AR(1) model, reflecting the short-term memory property, the GARCH(1,1) model, reflecting the volatility clustering property, and the FIGARCH model, reflecting the long-term memory property of the volatility time series. The memory effect in the AR(1) filtered return and volatility time series remained unchanged, while the long-term memory property diminished significantly in the volatility series of the GARCH(1,1) filtered data. Notably, there is no long-term memory property, when we eliminate the long-term memory property of volatility by the FIGARCH model. For all data used, although the Hurst exponents of the volatility time series changed considerably over time, those of the time series with the volatility clustering effect removed diminish significantly. Our results imply that the long-term memory property of the volatility time series can be attributed to the volatility clustering observed in the financial time series.

  20. Quality Changes During Long Term Farmers’ Stock Storage

    Science.gov (United States)

    Since 2012, U.S. annual peanut production has increased 44% from an average of 2.6 million MT compared with 1.8 million MT (1997 and 2012). This production increase has resulted in longer storage times between harvest and shelling. A study was conducted to observe the changes in quality of farmers...

  1. Long term modelling in a second rank world: application to climate policies

    International Nuclear Information System (INIS)

    Crassous, R.

    2008-11-01

    This research aims at the identification of the dissatisfaction reasons with respect to the existing climate models, at the design of an innovating modelling architecture which would respond to these dissatisfactions, and at proposing climate policy assessment pathways. The authors gives a critique assessment of the modelling activity within the field of climate policies, outlines the fact that the large number and the scattering of existing long term scenarios hides a weak control of uncertainties and of the inner consistency of the produced paths, as well as the very low number of modelling paradigms. After a deepened analysis of modelling practices, the author presents the IMACLIM-R modelling architecture which is presented on a world scale and includes 12 areas and 12 sectors, and allows the simulation of evolutions by 2050, and even 2100, with a one-year time step. The author describes a scenario without any climate policy, highlights reassessment possibilities for economical trajectories which would allow greenhouse gas concentration stabilisation on a long term basis through the application of IMACLIM-R innovations. He outlines adjustment and refinement possibilities for climate policies which would robustly limit the transition cost risks

  2. Phase changes in superaustenitic steels after long-term annealing

    Energy Technology Data Exchange (ETDEWEB)

    Svoboda, M.; Kroupa, A. [Inst. of Physics of Materials, Academy of Sciences of Czech Republic, Brno (Czech Republic); Sopousek, J.; Vrest' al, J. [Inst. of Theoretical and Physical Chemistry, Masaryk Univ., Brno (Czech Republic); Miodownik, P. [Thermotech Ltd, The Surrey Research Park, Guildford (United Kingdom)

    2004-11-01

    A structural study was performed on the austenitic steels Avesta 254 SMO and Avesta 654 SMO after annealing at 700 C for 500, 3188, and 6170 h. Both Avesta steels initially show an unexpectedly large amount of the Laves phase, followed by a relatively slow development of the Sigma phase with equilibrium apparently not yet reached after 3188 h. Thermodynamic calculations confirm that the driving forces for alternative precipitates are very similar thus making it easy to form metastable precipitates that only change very slowly to the equilibrium state. TTT calculations also confirm that the Laves phase precipitates earlier than the Sigma phase as the temperature is lowered. (orig.)

  3. Long-term (1993-2013) changes in macrozooplankton off the Western Antarctic Peninsula

    Science.gov (United States)

    Steinberg, Deborah K.; Ruck, Kate E.; Gleiber, Miram R.; Garzio, Lori M.; Cope, Joseph S.; Bernard, Kim S.; Stammerjohn, Sharon E.; Schofield, Oscar M. E.; Quetin, Langdon B.; Ross, Robin M.

    2015-07-01

    The Western Antarctic Peninsula (WAP) is one of the most rapidly warming regions on Earth, and where a high apex predator biomass is supported in large part by macrozooplankton. We examined trends in summer (January-February) abundance of major taxa of macrozooplankton along the WAP over two decades (1993-2013) and their relationship with environmental parameters (sea ice, atmospheric climate indices, sea surface temperature, and phytoplankton biomass and productivity). Macrozooplankton were collected from the top 120 m of the water column in a mid-Peninsula study region divided into latitudinal (North, South, and Far South) and cross-shelf (coastal, shelf, slope) sub-regions. Trends for krill species included a 5-year cycle in abundance peaks (positive anomalies) for Euphausia superba, but no directional long-term trend, and an increase in Thysanoessa macrura in the North; variability in both species was strongly influenced by primary production 2-years prior. E. crystallorophias abundance was best explained by the Southern Annular Mode (SAM) and Multivariate El Niño Southern Oscillation Index (MEI), and was more abundant in higher ice conditions. The salp Salpa thompsoni and thecosome pteropod Limacina helicina cycled between negative and positive anomalies in the North, but showed increasing positive anomalies in the South over time. Variation in salp and pteropod abundance was best explained by SAM and the MEI, respectively, and both species were more abundant in lower ice conditions. There was a long-term increase in some carnivorous gelatinous zooplankton (polychaete worm Tomopteris spp.) and amphipods. Abundance of Pseudosagitta spp. chaetognaths was closely related to SAM, with higher abundance tied to lower ice conditions. Long-term changes and sub-decadal cycles of WAP macrozooplankton community composition may affect energy transfer to higher trophic levels, and alter biogeochemical cycling in this seasonally productive and sensitive polar ecosystem.

  4. Quality changes of Antarctic krill powder during long term storage

    DEFF Research Database (Denmark)

    Nielsen, Nina Skall; Lu, Henna Fung Sieng; Bruheim, Inge

    2017-01-01

    of packaging in vacuum was observed. The stability was assessed by changes in concentrations of lipid classes, antioxidants, pyrroles and lipid, and Strecker-derived volatiles. Some degradation occurred during storage at room temperature. Thus, a minor increase in volatiles, an increase in free fatty acids...... and a concomitant decrease in antioxidants, tocopherol, and astaxanthin was observed. In addition, there was a minor decrease in phospholipids and n-3 fatty acids; however, storage at vacuum improved the oxidative stability of krill powder. Practical applications: For the use of krill powder in human nutrition......, it is important, that the quality and stability is sufficiently high to retain the nutritional value during storage. This study contributes with information about the stability during storage up to 12 months at room temperature and the effect of packaging the powder in vacuum. Antarctic krill (Euphausia superba...

  5. Hormonal changes during a long term isolation (SFINCSS-99 project)

    Science.gov (United States)

    Larina, I.; Custaud, M.; Gauquelin-Koch, G.; Gharib, C.; Grigoriev, A.; Nichiporuk, I.

    Long duration of space mission and functioning in Earth's orbit of the International Space Station make humans put up with spatial constraint for many months. From previous studies, it appears that confinement and inactivity can induce great psychological and physiological modifications by social and sensory deprivation. SFINCSS-99 experiment had the goal to determine the cardiovascular and the hormonal pattern of blood volume regulating hormones responses. Simulation experiments were performed in pressurized chambers outfitted with technical infrastructure including the systems for air regeneration, thermal and humidity air control, power supply, communications, TV monitoring, gas analysis and local electronic network. Three groups of test-subjects were functioning in parallel in adjacent modules, which mocked the ISS Russian and others segments. One33 crew (group I) occupied the 100 m module and the others the 200 m module (II &III). They could communicate and work together. Group I consisted from Russian males- volunteers aged of 37 to 48 who spent 240 days in chamber. Group II included 4 males (one German and three Russians) aged from 27 to 45, spent 110 days in isolation. In blood samples, drawing before, during and after isolation's period hormones were determined, in urine samples - excretion of hormones, electrolytes, nitrites, nitrates, and osmolality. The increase of plasma volume (hematocrit decrease in Group I was 13,2%: 42,7+/-0,5 vs 39,2+/-1,2; pGroup II - 4,1%: 44,3+/-1,0 vs 43,3+/-2,6) in association with a tendency to decrease in plasma renin activity (in Group I 13,1+/-3,5 vs 27,8+/-6,0) was likely to be due to decreased sympathetic activity, this do agree with the changes in urinary catecholamine (CA) during confinement. Urinary CA were significantly higher during the recovery period than during confinement (in Group I 341+/-44 vs 240+/-19, p< 0,05). This suggests that the sympathoadrenal system was activated, and agrees with the increase of

  6. Long term modelling in a second rank world: application to climate policies; Modeliser le long terme dans un monde de second rang: application aux politiques climatiques

    Energy Technology Data Exchange (ETDEWEB)

    Crassous, R

    2008-11-15

    This research aims at the identification of the dissatisfaction reasons with respect to the existing climate models, at the design of an innovating modelling architecture which would respond to these dissatisfactions, and at proposing climate policy assessment pathways. The authors gives a critique assessment of the modelling activity within the field of climate policies, outlines the fact that the large number and the scattering of existing long term scenarios hides a weak control of uncertainties and of the inner consistency of the produced paths, as well as the very low number of modelling paradigms. After a deepened analysis of modelling practices, the author presents the IMACLIM-R modelling architecture which is presented on a world scale and includes 12 areas and 12 sectors, and allows the simulation of evolutions by 2050, and even 2100, with a one-year time step. The author describes a scenario without any climate policy, highlights reassessment possibilities for economical trajectories which would allow greenhouse gas concentration stabilisation on a long term basis through the application of IMACLIM-R innovations. He outlines adjustment and refinement possibilities for climate policies which would robustly limit the transition cost risks.

  7. Potential breeding distributions of U.S. birds predicted with both short-term variability and long-term average climate data.

    Science.gov (United States)

    Bateman, Brooke L; Pidgeon, Anna M; Radeloff, Volker C; Flather, Curtis H; VanDerWal, Jeremy; Akçakaya, H Resit; Thogmartin, Wayne E; Albright, Thomas P; Vavrus, Stephen J; Heglund, Patricia J

    2016-12-01

    Climate conditions, such as temperature or precipitation, averaged over several decades strongly affect species distributions, as evidenced by experimental results and a plethora of models demonstrating statistical relations between species occurrences and long-term climate averages. However, long-term averages can conceal climate changes that have occurred in recent decades and may not capture actual species occurrence well because the distributions of species, especially at the edges of their range, are typically dynamic and may respond strongly to short-term climate variability. Our goal here was to test whether bird occurrence models can be predicted by either covariates based on short-term climate variability or on long-term climate averages. We parameterized species distribution models (SDMs) based on either short-term variability or long-term average climate covariates for 320 bird species in the conterminous USA and tested whether any life-history trait-based guilds were particularly sensitive to short-term conditions. Models including short-term climate variability performed well based on their cross-validated area-under-the-curve AUC score (0.85), as did models based on long-term climate averages (0.84). Similarly, both models performed well compared to independent presence/absence data from the North American Breeding Bird Survey (independent AUC of 0.89 and 0.90, respectively). However, models based on short-term variability covariates more accurately classified true absences for most species (73% of true absences classified within the lowest quarter of environmental suitability vs. 68%). In addition, they have the advantage that they can reveal the dynamic relationship between species and their environment because they capture the spatial fluctuations of species potential breeding distributions. With this information, we can identify which species and guilds are sensitive to climate variability, identify sites of high conservation value where climate

  8. Climate change

    International Nuclear Information System (INIS)

    2006-01-01

    This paper presented indicators of climate change for British Columbia (BC) with an emphasis on the coastal region. An overview of global effects of climate change was presented, as well as details of BC's current climate change action plan. Indicators examined in the paper for the BC coastal region included long-term trends in air temperature; long-term trends in precipitation; coastal ocean temperatures; sea levels on the BC coast; and the sensitivity of the BC coast to sea level rise and erosion. Data suggested that average air temperatures have become higher in many areas, and that Springtime temperatures have become warmer over the whole province. Winters have become drier in many areas of the province. Sea surface temperature has risen over the entire coast, with the North Coast and central Strait of Georgia showing the largest increases. Deep-water temperatures have also increased in 5 inlets on the South Coast. Results suggested that the direction and spatial pattern of the climate changes reported for British Columbia are consistent with broader trends in North America and the type of changes predicted by climate models for the region. Climate change will likely result in reduced snow-pack in southern BC. An earlier spring freshet on many snow-dominated river systems is anticipated as well as glacial retreat and disappearance. Warmer temperatures in some lakes and rivers are expected, as well as the increased frequency and severity of natural disturbances such as the pine mountain beetle. Large-scale shifts in ecosystems and the loss of certain ecosystems may also occur. BC's current climate plan includes cost effective actions that address GHG emissions and support efficient infrastructure and opportunities for innovation. Management programs for forest and agricultural lands have been initiated, as well as programs to reduce emissions from government operations. Research is also being conducted to understand the impacts of climate change on water

  9. Farmers' climate information needs for long-term adaptive decisions: A case study of almonds in CA

    Science.gov (United States)

    Jagannathan, K. A.; Jones, A. D.; Pathak, T. B.; Kerr, A. C.; Doll, D.

    2016-12-01

    Despite advances in climate modeling and projections, several sources report that current tools and models are not widely used in the agriculture sector. Farmers, depending on their local context, require information on very specific climatic metrics such as start of rains during the planting season, number of low temperature days during the growing season, etc. However, such specific climatic information is either not available, and/or is not synthesized and communicated in a manner that is accessible to these decision-makers. This research aims to bridge the gap between climate information and decision-making needs, by providing an improved understanding of what farmers' consider as relevant climate information, and how these needs compare with current modeling capabilities. Almond is a perennial crop, so any changes in climate within its 25-30 year lifetime can have an adverse impact on crop yield. This makes almond growers vulnerable to medium and long-term climate change. Hence, providing appropriate information on future climate projections can help guide their decisions on crop types & varieties, as well as management practices that are better adapted to future climatic conditions. Semi-structured exploratory interviews have been conducted with almond growers, farm advisors, and other industry stakeholders, with three goals: (1) to understand how growers have used climate information in the past; (2) to identify key climatic variables that are relevant - including appropriate temporal scales and acceptable uncertainty levels; and (3) to understand communication methods that could improve the usability of climate information for farm-level decision-making. The interviews showcased a great diversity amongst growers in terms of how they used weather/climate information. Discussions also indicated that there was a potential for climate information to impact long-term decisions, but only if it is provided within the right context, terminology, and communication

  10. Development of an integrated method for long-term water quality prediction using seasonal climate forecast

    Directory of Open Access Journals (Sweden)

    J. Cho

    2016-10-01

    Full Text Available The APEC Climate Center (APCC produces climate prediction information utilizing a multi-climate model ensemble (MME technique. In this study, four different downscaling methods, in accordance with the degree of utilizing the seasonal climate prediction information, were developed in order to improve predictability and to refine the spatial scale. These methods include: (1 the Simple Bias Correction (SBC method, which directly uses APCC's dynamic prediction data with a 3 to 6 month lead time; (2 the Moving Window Regression (MWR method, which indirectly utilizes dynamic prediction data; (3 the Climate Index Regression (CIR method, which predominantly uses observation-based climate indices; and (4 the Integrated Time Regression (ITR method, which uses predictors selected from both CIR and MWR. Then, a sampling-based temporal downscaling was conducted using the Mahalanobis distance method in order to create daily weather inputs to the Soil and Water Assessment Tool (SWAT model. Long-term predictability of water quality within the Wecheon watershed of the Nakdong River Basin was evaluated. According to the Korean Ministry of Environment's Provisions of Water Quality Prediction and Response Measures, modeling-based predictability was evaluated by using 3-month lead prediction data issued in February, May, August, and November as model input of SWAT. Finally, an integrated approach, which takes into account various climate information and downscaling methods for water quality prediction, was presented. This integrated approach can be used to prevent potential problems caused by extreme climate in advance.

  11. Long-term monitoring of change in Tropical grasslands- GLORIA network in the Andes

    Science.gov (United States)

    Cuesta, F. X.; Muriel, P.; Halloy, S.; Beck, S.; Meneses, R. I.; Irazabal, J.; Aguirre, N.; Viñas, P.; Suarez, D.; Becerra, M. T.; Gloria-Andes Network

    2013-05-01

    It has been shown that predicted warming and increased frequency of extreme weather events increase with altitude in the Andean mountains. Combined with enormous topographic (and hence precipitation) heterogeneity, poverty and intensive land use, creates in the region a situation of high vulnerability to global change. Since 2005 the network Global Research Initiative in Alpine Environment (GLORIA) sites have been progressively installed in Andean countries to monitor changes, document the type and magnitude of impacts and provide guidance to develop adaptation strategies for biodiversity, humans, and productive systems. We report the preliminary results from 10 of those sites, in addition to new sites planned in South America. These sites provide baseline data and identify processes and patterns in plant biodiversity across different geographic contexts. These preliminary results show the tremendous singularity of the vegetation and flora patterns in the study sites, suggesting high sensitivity of these ecosystems to climate anomalies. It is expected that the consolidation of this network will support and strengthen long-term observation and monitoring research programs to enable the documentation and understanding of climate change impacts on the Andean biota. Our research considers complementary modules of investigation (e.g. carbon stocks and fluxes, plant responses to experimental manipulation) that contextualize the challenges and opportunities of adaptation for biodiversity and socio-economic components, providing measures of trends as well as effectiveness of adaptive management strategies.

  12. Long-term environmental drivers of DOC fluxes: Linkages between management, hydrology and climate in a subtropical coastal estuary

    Science.gov (United States)

    Regier, Peter; Briceño, Henry; Jaffé, Rudolf

    2016-12-01

    Urban and agricultural development of the South Florida peninsula has disrupted historic freshwater flow in the Everglades, a hydrologically connected ecosystem stretching from central Florida to the Gulf of Mexico, USA. Current system-scale restoration efforts aim to restore natural hydrologic regimes to reestablish pre-drainage ecosystem functioning through increased water availability, quality and timing. Aquatic transport of carbon in this ecosystem, primarily as dissolved organic carbon (DOC), plays a critical role in biogeochemical cycling and food-web dynamics, and will be affected both by water management policies and climate change. To better understand DOC dynamics in South Florida estuaries and how hydrology, climate and water management may affect them, 14 years of monthly data collected in the Shark River estuary were used to examine DOC flux dynamics in a broader environmental context. Multivariate statistical methods were applied to long-term datasets for hydrology, water quality and climate to untangle the interconnected environmental drivers that control DOC export at monthly and annual scales. DOC fluxes were determined to be primarily controlled by hydrology but also by seasonality and long-term climate patterns and episodic weather events. A four-component model (salinity, rainfall, inflow, Atlantic Multidecadal Oscillation) capable of predicting DOC fluxes (R2 = 0.84, p water management and salinity.

  13. Synopsis of climate change

    Science.gov (United States)

    Angela Jardine; Jonathan Long

    2014-01-01

    Changes in climate can interact with other stressors to transform ecosystems and alter the services those ecosystems provide. This synopsis presents themes that run through the synthesis report regarding the impacts of a changing climate on the forests and waters of the synthesis area as well as long-term, broad-scale, science-based strategies to promote system...

  14. The changing flow of management information systems in long-term care facilities.

    Science.gov (United States)

    Stokes, D F

    1997-08-01

    Over the past three decades, the long-term care community has seen continual increases in the complexity and sophistication of management information systems. These changes have been brought about by the ever-increasing demands on owners and managers to provide accurate and timely data to both regulators and financial investors. The evolution of these systems has increased rapidly in recent years as the nation attempts to reinvent the funding mechanisms for long-term care.

  15. Long-term space changes after premature loss of a primary maxillary first molar

    OpenAIRE

    Lin, Yng-Tzer J.; Lin, Yai-Tin

    2016-01-01

    Background/purpose: The consequence of premature loss of primary teeth resulting in the need for space maintainers has been controversial for many years. There is no longitudinal long-term report in literature regarding the premature loss of a primary maxillary first molar. The aim of this study was to continue observing the long-term space changes of 19 cases following premature loss of a primary maxillary first molar during the transition from primary to permanent dentition. Materials an...

  16. Long term ice sheet mass change rates and inter-annual variability from GRACE gravimetry.

    Science.gov (United States)

    Harig, C.

    2017-12-01

    The GRACE time series of gravimetry now stretches 15 years since its launch in 2002. Here we use Slepian functions to estimate the long term ice mass trends of Greenland, Antarctica, and several glaciated regions. The spatial representation shows multi-year to decadal regional shifts in accelerations, in agreement with increases in radar derived ice velocity. Interannual variations in ice mass are of particular interest since they can directly link changes in ice sheets to the drivers of change in the polar ocean and atmosphere. The spatial information retained in Slepian functions provides a tool to determine how this link varies in different regions within an ice sheet. We present GRACE observations of the 2013-2014 slowdown in mass loss of the Greenland ice sheet, which was concentrated in specific parts of the ice sheet and in certain months of the year. We also discuss estimating the relative importance of climate factors that control ice mass balance, as a function of location of the glacier/ice cap as well as the spatial variation within an ice sheet by comparing gravimetry with observations of surface air temperature, ocean temperature, etc. as well as model data from climate reanalysis products.

  17. Drivers of inter-annual variation and long-term change in High-Arctic spider species abundances

    DEFF Research Database (Denmark)

    Bowden, Joseph J.; Hansen, Oskar L. P.; Olsen, Kent

    2018-01-01

    Understanding how species abundances vary in space and time is a central theme in ecology, yet there are few long-term field studies of terrestrial invertebrate abundances and the determinants of their dynamics. This is particularly relevant in the context of rapid climate change occurring...... in the Arctic. Arthropods can serve as strong indicators of ecosystem change due to their sensitivity to increasing temperatures and other environmental variables. We used spider samples collected by pitfall trapping from three different habitats (fen, mesic and arid heath) in High-Arctic Greenland to assess...... interpretation of long-term trends. We used model selection to determine which climatic variables and/or previous years’ abundance best explained annual variation in species abundances over this period. We identified and used 28 566 adult spiders that comprised eight species. Most notably, the abundances of some...

  18. Surface ozone in China: present-day distribution and long-term changes

    Science.gov (United States)

    Xu, X.; Lin, W.; Xu, W.

    2017-12-01

    Reliable knowledge of spatio-temporal variations of surface ozone is highly needed to assess the impacts of ozone on human health, ecosystem and climate. Although regional distributions and trends of surface ozone in European and North American countries have been well characterized, little is known about the variability of surface ozone in many other countries, including China, where emissions of ozone precursors have been changing rapidly in recent decades. Here we present the first comprehensive description of present-day (2013-2017) distribution and long-term changes of surface ozone in mainland China. Recent ozone measurements from China's air quality monitoring network (AQMN) are analyzed to show present-day distributions of a few ozone exposure metrics for urban environment. Long-term measurements of ozone at six background sites, a rural site and an urban are used to study the trends of ozone in background, rural and urban air, respectively. The average levels of ozone at the AQMN sites (mainly urban) are close to those found at many European and North American sites. However, ozone at most of the sites shows very large diurnal and seasonal variations so that ozone nonattainment can occur in many cities, particularly those in the North China Plain (NCP), the south of Northeast China (NEC), the Yangtze River Delta (YRD), the Pearl River Delta (PRD), and the Sichuan Basin-Chongqing region (SCB). In all these regions, particularly in the NCP, the maximum daily 8-h average (MDA8) ozone concentration can significantly exceed the national limit (75 ppb). High annual sum of ozone means over 35 ppb (SOMO35) exist mainly in the NCP, NEC and YRD, with regional averages over 4000 ppb·d. Surface ozone has significantly increased at Waliguan (a baseline site in western China) and Shangdianzi (a background site in the NCP), and decreased in winter and spring at Longfengshan (a background site in Northeast China). No clear trend can be derived from long-term measurements

  19. Zero emission targets as long-term global goals for climate protection

    International Nuclear Information System (INIS)

    Rogelj, Joeri; Riahi, Keywan; Schaeffer, Michiel; Hare, William; Meinshausen, Malte; Knutti, Reto; Alcamo, Joseph

    2015-01-01

    Recently, assessments have robustly linked stabilization of global-mean temperature rise to the necessity of limiting the total amount of emitted carbon-dioxide (CO 2 ). Halting global warming thus requires virtually zero annual CO 2 emissions at some point. Policymakers have now incorporated this concept in the negotiating text for a new global climate agreement, but confusion remains about concepts like carbon neutrality, climate neutrality, full decarbonization, and net zero carbon or net zero greenhouse gas (GHG) emissions. Here we clarify these concepts, discuss their appropriateness to serve as a long-term global benchmark for achieving temperature targets, and provide a detailed quantification. We find that with current pledges and for a likely (>66%) chance of staying below 2 °C, the scenario literature suggests net zero CO 2 emissions between 2060 and 2070, with net negative CO 2 emissions thereafter. Because of residual non-CO 2 emissions, net zero is always reached later for total GHG emissions than for CO 2 . Net zero emissions targets are a useful focal point for policy, linking a global temperature target and socio-economic pathways to a necessary long-term limit on cumulative CO 2 emissions. (letter)

  20. Long-term and realistic global change manipulations had low impact on diversity of soil biota in temperate heathland

    DEFF Research Database (Denmark)

    Holmstrup, Martin; Damgaard, Christian; Schmidt, Inger K

    2017-01-01

    C:N ratio. After eight years of treatment, however, the CO2-increased litter C:N ratio did not influence the diversity in any of the four fauna groups. The number of significant correlations between treatments, food source quality, and soil biota diversities was reduced from six to three after two...... and eight years, respectively. These results suggest a remarkable resilience within the soil biota against global climate change treatments in the long term....

  1. Evidence of long-term change in zonal wind in the tropical lower mesosphere: Observations and model simulations

    Czech Academy of Sciences Publication Activity Database

    Ratnam, M. V.; Kumar, G. K.; Rao, N. V.; Murthy, B. V. K.; Laštovička, Jan; Qian, L.

    2013-01-01

    Roč. 40, č. 2 (2013), s. 397-401 ISSN 0094-8276 R&D Projects: GA ČR GAP209/10/1792 Institutional support: RVO:68378289 Keywords : mesosphere * zonal wind * long-term trends * TIME-GCM * climate change Subject RIV: DG - Athmosphere Sciences, Meteorology Impact factor: 4.456, year: 2013 http://onlinelibrary.wiley.com/doi/10.1002/grl.50158/abstract

  2. Excavation-drier method of energy-peat extraction reduces long-term climatic impact

    Energy Technology Data Exchange (ETDEWEB)

    Silvan, N.; Silvan, K.; Laine, J. [Finnish Forest Research Inst., Parkano (Finland)], e-mail: niko.silvan@metla.fi; Vaisanen, S.; Soukka, R. [Lappeenranta Univ.of Techology (Finland)

    2012-11-01

    Climatic impacts of energy-peat extraction are of increasing concern due to EU emissions trading requirements. A new excavation-drier peat extraction method has been developed to reduce the climatic impact and increase the efficiency of peat extraction. To quantify and compare the soil GHG fluxes of the excavation drier and the traditional milling methods, as well as the areas from which the energy peat is planned to be extracted in the future (extraction reserve area types), soil CO{sub 2}, CH{sub 4} and N{sub 2}O fluxes were measured during 2006-2007 at three sites in Finland. Within each site, fluxes were measured from drained extraction reserve areas, extraction fields and stockpiles of both methods and additionally from the biomass driers of the excavation-drier method. The Life Cycle Assessment (LCA), described at a principal level in ISO Standards 14040:2006 and 14044:2006, was used to assess the long-term (100 years) climatic impact from peatland utilisation with respect to land use and energy production chains where utilisation of coal was replaced with peat. Coal was used as a reference since in many cases peat and coal can replace each other in same power plants. According to this study, the peat extraction method used was of lesser significance than the extraction reserve area type in regards to the climatic impact. However, the excavation-drier method seems to cause a slightly reduced climatic impact as compared with the prevailing milling method. (orig.)

  3. Long-term temporal changes in the occurrence of a high forest fire danger in Finland

    Directory of Open Access Journals (Sweden)

    H. M. Mäkelä

    2012-08-01

    Full Text Available Climate variation and change influence several ecosystem components including forest fires. To examine long-term temporal variations of forest fire danger, a fire danger day (FDD model was developed. Using mean temperature and total precipitation of the Finnish wildfire season (June–August, the model describes the climatological preconditions of fire occurrence and gives the number of fire danger days during the same time period. The performance of the model varied between different regions in Finland being best in south and west. In the study period 1908–2011, the year-to-year variation of FDD was large and no significant increasing or decreasing tendencies could be found. Negative slopes of linear regression lines for FDD could be explained by the simultaneous, mostly not significant increases in precipitation. Years with the largest wildfires did not stand out from the FDD time series. This indicates that intra-seasonal variations of FDD enable occurrence of large-scale fires, despite the whole season's fire danger is on an average level. Based on available monthly climate data, it is possible to estimate the general fire conditions of a summer. However, more detailed input data about weather conditions, land use, prevailing forestry conventions and socio-economical factors would be needed to gain more specific information about a season's fire risk.

  4. Changing climate, changing frames

    International Nuclear Information System (INIS)

    Vink, Martinus J.; Boezeman, Daan; Dewulf, Art; Termeer, Catrien J.A.M.

    2013-01-01

    Highlights: ► We show development of flood policy frames in context of climate change attention. ► Rising attention on climate change influences traditional flood policy framing. ► The new framing employs global-scale scientific climate change knowledge. ► With declining attention, framing disregards climate change, using local knowledge. ► We conclude that frames function as sensemaking devices selectively using knowledge. -- Abstract: Water management and particularly flood defence have a long history of collective action in low-lying countries like the Netherlands. The uncertain but potentially severe impacts of the recent climate change issue (e.g. sea level rise, extreme river discharges, salinisation) amplify the wicked and controversial character of flood safety policy issues. Policy proposals in this area generally involve drastic infrastructural works and long-term investments. They face the difficult challenge of framing problems and solutions in a publicly acceptable manner in ever changing circumstances. In this paper, we analyse and compare (1) how three key policy proposals publicly frame the flood safety issue, (2) the knowledge referred to in the framing and (3) how these frames are rhetorically connected or disconnected as statements in a long-term conversation. We find that (1) framings of policy proposals differ in the way they depict the importance of climate change, the relevant timeframe and the appropriate governance mode; (2) knowledge is selectively mobilised to underpin the different frames and (3) the frames about these proposals position themselves against the background of the previous proposals through rhetorical connections and disconnections. Finally, we discuss how this analysis hints at the importance of processes of powering and puzzling that lead to particular framings towards the public at different historical junctures

  5. Long-term pattern and magnitude of soil carbon feedback to the climate system in a warming world.

    Science.gov (United States)

    Melillo, J M; Frey, S D; DeAngelis, K M; Werner, W J; Bernard, M J; Bowles, F P; Pold, G; Knorr, M A; Grandy, A S

    2017-10-06

    In a 26-year soil warming experiment in a mid-latitude hardwood forest, we documented changes in soil carbon cycling to investigate the potential consequences for the climate system. We found that soil warming results in a four-phase pattern of soil organic matter decay and carbon dioxide fluxes to the atmosphere, with phases of substantial soil carbon loss alternating with phases of no detectable loss. Several factors combine to affect the timing, magnitude, and thermal acclimation of soil carbon loss. These include depletion of microbially accessible carbon pools, reductions in microbial biomass, a shift in microbial carbon use efficiency, and changes in microbial community composition. Our results support projections of a long-term, self-reinforcing carbon feedback from mid-latitude forests to the climate system as the world warms. Copyright © 2017 The Authors, some rights reserved; exclusive licensee American Association for the Advancement of Science. No claim to original U.S. Government Works.

  6. Long-term ice sheet-climate interactions under anthropogenic greenhouse forcing simulated with a complex Earth System Model

    Energy Technology Data Exchange (ETDEWEB)

    Vizcaino, Miren [Max-Planck-Institut fuer Meteorologie, Hamburg (Germany); University of California, Department of Geography, Berkeley, CA (United States); Mikolajewicz, Uwe; Maier-Reimer, Ernst [Max-Planck-Institut fuer Meteorologie, Hamburg (Germany); Groeger, Matthias [Max-Planck-Institut fuer Meteorologie, Hamburg (Germany); IFM-GEOMAR, Kiel (Germany); Schurgers, Guy [Max-Planck-Institut fuer Meteorologie, Hamburg (Germany); Lund University, Department of Physical Geography and Ecosystems Analysis, Lund (Sweden); Winguth, Arne M.E. [Center for Climatic Research, Department of Atmospheric and Oceanic Sciences, Madison (United States)

    2008-11-15

    Several multi-century and multi-millennia simulations have been performed with a complex Earth System Model (ESM) for different anthropogenic climate change scenarios in order to study the long-term evolution of sea level and the impact of ice sheet changes on the climate system. The core of the ESM is a coupled coarse-resolution Atmosphere-Ocean General Circulation Model (AOGCM). Ocean biogeochemistry, land vegetation and ice sheets are included as components of the ESM. The Greenland Ice Sheet (GrIS) decays in all simulations, while the Antarctic ice sheet contributes negatively to sea level rise, due to enhanced storage of water caused by larger snowfall rates. Freshwater flux increases from Greenland are one order of magnitude smaller than total freshwater flux increases into the North Atlantic basin (the sum of the contribution from changes in precipitation, evaporation, run-off and Greenland meltwater) and do not play an important role in changes in the strength of the North Atlantic Meridional Overturning Circulation (NAMOC). The regional climate change associated with weakening/collapse of the NAMOC drastically reduces the decay rate of the GrIS. The dynamical changes due to GrIS topography modification driven by mass balance changes act first as a negative feedback for the decay of the ice sheet, but accelerate the decay at a later stage. The increase of surface temperature due to reduced topographic heights causes a strong acceleration of the decay of the ice sheet in the long term. Other feedbacks between ice sheet and atmosphere are not important for the mass balance of the GrIS until it is reduced to 3/4 of the original size. From then, the reduction in the albedo of Greenland strongly accelerates the decay of the ice sheet. (orig.)

  7. Long-term solar activity and its implications to the heliosphere, geomagnetic activity, and the Earth’s climate

    Directory of Open Access Journals (Sweden)

    Tanskanen Eija

    2013-06-01

    Full Text Available The Sun’s long-term magnetic variability is the primary driver of space climate. This variability is manifested not only in the long-observed and dramatic change of magnetic fields on the solar surface, but also in the changing solar radiative output across all wavelengths. The Sun’s magnetic variability also modulates the particulate and magnetic fluxes in the heliosphere, which determine the interplanetary conditions and impose significant electromagnetic forces and effects upon planetary atmospheres. All these effects due to the changing solar magnetic fields are also relevant for planetary climates, including the climate of the Earth. The ultimate cause of solar variability, at time scales much shorter than stellar evolutionary time scales, i.e., at decadal to centennial and, maybe, even millennial or longer scales, has its origin in the solar dynamo mechanism. Therefore, in order to better understand the origin of space climate, one must analyze different proxies of solar magnetic variability and develop models of the solar dynamo mechanism that correctly produce the observed properties of the magnetic fields. This Preface summarizes the most important findings of the papers of this Special Issue, most of which were presented in the Space Climate-4 Symposium organized in 2011 in Goa, India.

  8. Transitions to Sustainable Development. New Directions in the Study of Long Term Transformative Change

    International Nuclear Information System (INIS)

    Grin, J.; Rotmans, J.; Schot, J.; Geels, F.; Loorbach, D.

    2010-01-01

    Over the past few decades, there has been a growing concern about the social and environmental risks which have come along with the progress achieved through a variety of mutually intertwined modernization processes. In recent years these concerns are transformed into a widely-shared sense of urgency, partly due to events such as the various pandemics threatening livestock, and increasing awareness of the risks and realities of climate change, and the energy and food crises. This sense of urgency includes an awareness that our entire social system is in need of fundamental transformation. But like the earlier transition between the 1750s and 1890s from a pre-modern to a modern industrial society, this second transition is also a contested one. Sustainable development is only one of many options. This book addresses the issue on how to understand the dynamics and governance of the second transition dynamics in order to ensure sustainable development. It will be necessary reading for students and scholars with an interest in sustainable development and long-term transformative change.

  9. Transitions to Sustainable Development. New Directions in the Study of Long Term Transformative Change

    Energy Technology Data Exchange (ETDEWEB)

    Grin, J. [Department of Political Science, University of Amsterdam, Amsterdam (Netherlands); Rotmans, J. [Sustainability Transitions and Transition Management, Erasmus University Rotterdam, Rotterdam (Netherlands); Schot, J. [Eindhoven University of Technology, Eindhoven (Netherlands); Geels, F. [Science Policy Research Unit SPRU, University of Sussex, Brighton (United Kingdom); Loorbach, D. [Dutch Research Institute for Transitions Drift, Erasmus University Rotterdam, Rotterdam (Netherlands)

    2010-07-01

    Over the past few decades, there has been a growing concern about the social and environmental risks which have come along with the progress achieved through a variety of mutually intertwined modernization processes. In recent years these concerns are transformed into a widely-shared sense of urgency, partly due to events such as the various pandemics threatening livestock, and increasing awareness of the risks and realities of climate change, and the energy and food crises. This sense of urgency includes an awareness that our entire social system is in need of fundamental transformation. But like the earlier transition between the 1750s and 1890s from a pre-modern to a modern industrial society, this second transition is also a contested one. Sustainable development is only one of many options. This book addresses the issue on how to understand the dynamics and governance of the second transition dynamics in order to ensure sustainable development. It will be necessary reading for students and scholars with an interest in sustainable development and long-term transformative change.

  10. Surviving in Changing Seascapes: Sediment Dynamics as Bottleneck for Long-Term Seagrass Presence

    NARCIS (Netherlands)

    Suykerbuyk, W.; Bouma, T.J.; Govers, L.L.; Giesen, K.; de Jong, D.J.; Herman, P.M.J.; Hendriks, J.; van Katwijk, M.M.

    2016-01-01

    Changes in the seascape often result in altered hydrodynamics that lead to coinciding changes in sediment dynamics. Little is known on how altered sediment dynamics affect long-term seagrass persistence. We studied the thresholds of sediment dynamics in relation to seagrass presence by comparing

  11. Medium- and Long-term Prediction of LOD Change with the Leap-step Autoregressive Model

    Science.gov (United States)

    Liu, Q. B.; Wang, Q. J.; Lei, M. F.

    2015-09-01

    It is known that the accuracies of medium- and long-term prediction of changes of length of day (LOD) based on the combined least-square and autoregressive (LS+AR) decrease gradually. The leap-step autoregressive (LSAR) model is more accurate and stable in medium- and long-term prediction, therefore it is used to forecast the LOD changes in this work. Then the LOD series from EOP 08 C04 provided by IERS (International Earth Rotation and Reference Systems Service) is used to compare the effectiveness of the LSAR and traditional AR methods. The predicted series resulted from the two models show that the prediction accuracy with the LSAR model is better than that from AR model in medium- and long-term prediction.

  12. Long-term trends of heat stress and energy use implications in subtropical climates

    Energy Technology Data Exchange (ETDEWEB)

    Lam, Joseph C.; Wan, Kevin K.W.; Wong, S.L.; Lam, Tony N.T. [Building Energy Research Group, Department of Building and Construction, City University of Hong Kong, Tat Chee Avenue, Kowloon, Hong Kong SAR (China)

    2010-02-15

    Past and future trends of human comfort in terms of heat and cold stresses under the local subtropical climates using measured meteorological data as well as predictions from general climate models were investigated. Summer discomfort showed an increasing trend (and winter discomfort a decreasing trend) over the past 41 years from 1968 to 2008. Monthly mean minimum and maximum temperatures and moisture content predictions from a general climate model (MIROC3.2-H) were used to determine summer and winter discomfort for future years (2009-2100) based on two emissions scenarios B1 and A1B (low and medium forcing). The 92-year (2009-2100) mean cold stress would be reduced from the 41-year (1968-2008) mean value of 8.7 to about three for both emissions scenarios. The 92-year mean heat stress would be 115.9 and 120.6 for B1 and A1B, respectively, representing 31.6% and 36.9% increase over the 1968-2008 long-term average of 88.1. These suggest that the already small winter heating requirement in subtropical Hong Kong would become even more insignificant in future years, whereas the increasing trend of summer discomfort would result in more cooling demand in the built environment. (author)

  13. Short-term changes in arterial inflammation predict long-term changes in atherosclerosis progression

    Energy Technology Data Exchange (ETDEWEB)

    Joseph, Philip [Massachusetts General Hospital and Harvard Medical School, Cardiology Division and Cardiac MR PET CT Program, Boston, MA (United States); McMaster University, Population Health Research Institute, Department of Medicine, and Department of Radiology, Hamilton, ON (Canada); Ishai, Amorina; Tawakol, Ahmed [Massachusetts General Hospital and Harvard Medical School, Cardiology Division and Cardiac MR PET CT Program, Boston, MA (United States); Mani, Venkatesh [Icahn School of Medicine at Mount Sinai School of Medicine, Translational and Molecular Imaging Institute and Department of Radiology, New York, NY (United States); Kallend, David [The Medicines Company, Parsippany, NJ (United States); Rudd, James H.F. [University of Cambridge, Division of Cardiovascular Medicine, Cambridge (United Kingdom); Fayad, Zahi A. [Icahn School of Medicine at Mount Sinai School of Medicine, Translational and Molecular Imaging Institute and Department of Radiology, New York, NY (United States); Icahn School of Medicine at Mount Sinai School of Medicine, Hess CSM Building Floor TMII, Rm S1-104, Translational and Molecular Imaging Institute and Department of Radiology, New York, NY (United States)

    2017-01-15

    It remains unclear whether changes in arterial wall inflammation are associated with subsequent changes in the rate of structural progression of atherosclerosis. In this sub-study of the dal-PLAQUE clinical trial, multi-modal imaging was performed using 18-fludeoxyglucose (FDG) positron emission tomography (PET, at 0 and 6 months) and magnetic resonance imaging (MRI, at 0 and 24 months). The primary objective was to determine whether increasing FDG uptake at 6 months predicted atherosclerosis progression on MRI at 2 years. Arterial inflammation was measured by the carotid FDG target-to-background ratio (TBR), and atherosclerotic plaque progression was defined as the percentage change in carotid mean wall area (MWA) and mean wall thickness (MWT) on MRI between baseline and 24 months. A total of 42 participants were included in this sub-study. The mean age of the population was 62.5 years, and 12 (28.6 %) were women. In participants with (vs. without) any increase in arterial inflammation over 6 months, the long-term changes in both MWT (% change MWT: 17.49 % vs. 1.74 %, p = 0.038) and MWA (% change MWA: 25.50 % vs. 3.59 %, p = 0.027) were significantly greater. Results remained significant after adjusting for clinical and biochemical covariates. Individuals with no increase in arterial inflammation over 6 months had no significant structural progression of atherosclerosis over 24 months as measured by MWT (p = 0.616) or MWA (p = 0.373). Short-term changes in arterial inflammation are associated with long-term structural atherosclerosis progression. These data support the concept that therapies that reduce arterial inflammation may attenuate or halt progression of atherosclerosis. (orig.)

  14. Short-term changes in arterial inflammation predict long-term changes in atherosclerosis progression

    International Nuclear Information System (INIS)

    Joseph, Philip; Ishai, Amorina; Tawakol, Ahmed; Mani, Venkatesh; Kallend, David; Rudd, James H.F.; Fayad, Zahi A.

    2017-01-01

    It remains unclear whether changes in arterial wall inflammation are associated with subsequent changes in the rate of structural progression of atherosclerosis. In this sub-study of the dal-PLAQUE clinical trial, multi-modal imaging was performed using 18-fludeoxyglucose (FDG) positron emission tomography (PET, at 0 and 6 months) and magnetic resonance imaging (MRI, at 0 and 24 months). The primary objective was to determine whether increasing FDG uptake at 6 months predicted atherosclerosis progression on MRI at 2 years. Arterial inflammation was measured by the carotid FDG target-to-background ratio (TBR), and atherosclerotic plaque progression was defined as the percentage change in carotid mean wall area (MWA) and mean wall thickness (MWT) on MRI between baseline and 24 months. A total of 42 participants were included in this sub-study. The mean age of the population was 62.5 years, and 12 (28.6 %) were women. In participants with (vs. without) any increase in arterial inflammation over 6 months, the long-term changes in both MWT (% change MWT: 17.49 % vs. 1.74 %, p = 0.038) and MWA (% change MWA: 25.50 % vs. 3.59 %, p = 0.027) were significantly greater. Results remained significant after adjusting for clinical and biochemical covariates. Individuals with no increase in arterial inflammation over 6 months had no significant structural progression of atherosclerosis over 24 months as measured by MWT (p = 0.616) or MWA (p = 0.373). Short-term changes in arterial inflammation are associated with long-term structural atherosclerosis progression. These data support the concept that therapies that reduce arterial inflammation may attenuate or halt progression of atherosclerosis. (orig.)

  15. a system approach to the long term forecasting of the climat data in baikal region

    Science.gov (United States)

    Abasov, N.; Berezhnykh, T.

    2003-04-01

    The Angara river running from Baikal with a cascade of hydropower plants built on it plays a peculiar role in economy of the region. With view of high variability of water inflow into the rivers and lakes (long-term low water periods and catastrophic floods) that is due to climatic peculiarities of the water resource formation, a long-term forecasting is developed and applied for risk decreasing at hydropower plants. Methodology and methods of long-term forecasting of natural-climatic processes employs some ideas of the research schools by Academician I.P.Druzhinin and Prof. A.P.Reznikhov and consists in detailed investigation of cause-effect relations, finding out physical analogs and their application to formalized methods of long-term forecasting. They are divided into qualitative (background method; method of analogs based on solar activity), probabilistic and approximative methods (analog-similarity relations; discrete-continuous model). These forecasting methods have been implemented in the form of analytical aids of the information-forecasting software "GIPSAR" that provides for some elements of artificial intelligence. Background forecasts of the runoff of the Ob, the Yenisei, the Angara Rivers in the south of Siberia are based on space-time regularities that were revealed on taking account of the phase shifts in occurrence of secular maxima and minima on integral-difference curves of many-year hydrological processes in objects compared. Solar activity plays an essential role in investigations of global variations of climatic processes. Its consideration in the method of superimposed epochs has allowed a conclusion to be made on the higher probability of the low-water period in the actual inflow to Lake Baikal that takes place on the increasing branch of solar activity of its 11-year cycle. The higher probability of a high-water period is observed on the decreasing branch of solar activity from the 2nd to the 5th year after its maximum. Probabilistic method

  16. Long term SAR interferometry monitoring for assessing changing levels of slope instability hazards

    Science.gov (United States)

    Wasowski, J.; Ferretti, A.

    The population growth with increasing impact of man on the environment and urbanisation of areas susceptible to slope failures coupled with the ongoing change in climate patterns will require a shift in the approaches to landslide hazard reduction Indeed there is evidence that landslide activity and related socio-economic loss are increasing in both rich and less developed countries throughout the world Because of this and because the urbanisation of hillside and mountain slopes prone to failure will likely continue in the future the protection of new and pre-existing developed areas via traditional engineering stabilisation works and in situ monitoring is not considered economically feasible Furthermore in most cases the ground control systems are installed post-factum and for short term monitoring and hence their role in preventing disasters is limited Considering the global dimension of the slope instability problem a sustainable road to landslide hazard reduction seems to be via exploitation of EO systems with focus on early detection long term monitoring and early warning Thanks to the wide-area coverage regular schedule and improving resolution of space-borne sensors the EO can foster the auspicious shift from a culture of repair to a culture of awarness and prevention Under this scenario the space-borne synthetic aperture radar differential interferometry DInSAR is attractive because of its capability to provide both wide-area and spatially dense information on surface displacements Since the presence of movements represents a direct evidence of

  17. Ontong Java volcanism initiated long-term climate warming that caused substantial changes in terrestrial vegetation several tens of thousand years before the onset of OAE1a (Early Aptian, Cretaceous)

    Science.gov (United States)

    Keller, Christina E.; Hochuli, Peter A.; Giorgioni, Martino; Garcia, Therese I.; Bernasconi, Stefano M.; Weissert, Helmut

    2010-05-01

    During Cretaceous times, several intense volcanic episodes are proposed as trigger for episodic climate warming, for changes in marine circulation patterns and for elevated marine productivity, which resulted in the widespread black shale deposits of the Oceanic Anoxic Events (OAE). In the sediments underlying the early Aptian OAE1a black shales, a prominent negative carbon isotope excursion is recorded. Its origin had long been controversial (e.g. Arthur, 2000; Jahren et al., 2001) before recent studies attributed it to the Ontong Java volcanism (Méhay et al., 2009; Tejada et al., 2009). Volcanic outgassing results in an increased pCO2 and should lead to a rise in global temperatures. We therefore investigated if the volcanically-induced increase in pCO2 at the onset of OAE1a in the early Aptian led to a temperature rise that was sufficient to affect terrestrial vegetation assemblages. In order to analyse changes in terrestrial palynomorph assemblages, we examined 15 samples from 12 black shale horizons throughout the early Aptian negative C-isotope spike interval of the Pusiano section (Maiolica Formation; N-Italy). These sediments were deposited at the southern continental margin of the alpine Tethys Ocean and have been bio- and magnetostratigraphically dated by Channell et al. (1995). In order to obtain a continuous palynological record of the negative C-isotope spike interval and the base of OAE1a, we combined this pre-OAE1a interval of Pusiano with the OAE1a interval of the nearby Cismon section (Hochuli et al., 1999). The sporomorph assemblages at the base of this composite succession feature abundant bisaccate pollen, which reflects a warm-temperate climate. Rather arid conditions are inferred from low trilete spore percentages. Several tens of thousand years before the onset of OAE1a, C-isotope values started to decrease. Some thousand years later, bisaccate pollen began to decrease, whereas an increase of Classopollis spp. and Araucariacites spp

  18. Assessment of short- and long-term memory in trends of major climatic variables over Iran: 1966-2015

    Science.gov (United States)

    Mianabadi, Ameneh; Shirazi, Pooya; Ghahraman, Bijan; Coenders-Gerrits, A. M. J.; Alizadeh, Amin; Davary, Kamran

    2018-02-01

    In arid and semi-arid regions, water scarcity is the crucial issue for crop production. Identifying the spatial and temporal trends in aridity, especially during the crop-growing season, is important for farmers to manage their agricultural practices. This will become especially relevant when considering climate change projections. To reliably determine the actual trends, the influence of short- and long-term memory should be removed from the trend analysis. The objective of this study is to investigate the effect of short- and long-term memory on estimates of trends in two aridity indicators—the inverted De Martonne (ϕ IDM ) and Budyko (ϕ B ) indices. The analysis is done using precipitation and temperature data over Iran for a 50-year period (1966-2015) at three temporal scales: annual, wheat-growing season (October-June), and maize-growing season (May-November). For this purpose, the original and the modified Mann-Kendall tests (i.e., modified by three methods of trend free pre-whitening (TFPT), effective sample size (ESS), and long-term persistence (LTP)) are used to investigate the temporal trends in aridity indices, precipitation, and temperature by taking into account the effect of short- and long-term memory. Precipitation and temperature data were provided by the Islamic Republic of Iran Meteorological Organization (IRIMO). The temporal trend analysis showed that aridity increased from 1966 to 2015 at the annual and wheat-growing season scales, which is due to a decreasing trend in precipitation and an increasing trend in mean temperature at these two timescales. The trend in aridity indices was decreasing in the maize-growing season, since precipitation has an increasing trend for most parts of Iran in that season. The increasing trend in aridity indices is significant in Western Iran, which can be related to the significantly more negative trend in precipitation in the West. This increasing trend in aridity could result in an increasing crop water

  19. Social Stairs : taking the Piano Staircase towards long-term behavioral change

    NARCIS (Netherlands)

    Peeters, M.M.R.; Megens, C.J.P.G.; Hoven, van den E.A.W.H.; Hummels, C.C.M.; Brombacher, A.C.; Berkovsky, S.; Freyne, J.

    2013-01-01

    This paper addresses the development of Social Stairs, an intelligent musical staircase to change people’s behavior in the long-term to take the stairs in favor of the elevator. Through designing with the Experiential Design Landscape (EDL) method, a design opportunity was found that social

  20. Long-Term Developmental Changes in Children's Lower-Order Big Five Personality Facets

    NARCIS (Netherlands)

    A.D. de Haan (Amaranta); S.S.W. de Pauw (Sarah); A.L. van den Akker (Alithe); M. Deković (Maja); P.J. Prinzie (Peter)

    2016-01-01

    markdownabstract__Objective:__ This study examined long-term developmental changes in mother-rated lower-order facets of children's Big Five dimensions. __Method:__ Two independent community samples covering early childhood (2-4.5 years; N=365, 39% girls) and middle childhood to the end of middle

  1. Long-term developmental changes in children's lower-order Big Five personality facets

    NARCIS (Netherlands)

    Haan, A.D. de; Pauw, S. de; Akker, A.J. van den; Dekovic, M.; Prinzie, P.

    2017-01-01

    Objective: This study examined long-term developmental changes in mother-rated lower-order facets of children's Big Five dimensions. Method: Two independent community samples covering early childhood (2-4.5 years; N = 365, 39% girls) and middle childhood to the end of middle adolescence (6-17 years;

  2. Long-term developmental changes in children’s lower-order big five personality facets

    NARCIS (Netherlands)

    de Haan, A.; de Pauw, S.; van den Akker, A.; Deković, M.; Prinzie, P.

    2017-01-01

    Objective This study examined long-term developmental changes in mother-rated lower-order facets of children's Big Five dimensions. Method Two independent community samples covering early childhood (2–4.5 years; N = 365, 39% girls) and middle childhood to the end of middle adolescence (6–17 years;

  3. Long-term developmental changes in children’s lower-order Big Five personality facets

    NARCIS (Netherlands)

    de Haan, A.D.; de Pauw, S.; van den Akker, A.L.; Dekovic, M.; Prinzie, Peter

    2017-01-01

    Objective This study examined long-term developmental changes in mother-rated lower-order facets of children's Big Five dimensions. Method Two independent community samples covering early childhood (2–4.5 years; N = 365, 39% girls) and middle childhood to the end of middle adolescence (6–17 years;

  4. How Do You Motivate Long-Term Behavior Change to Prevent Cancer?

    Science.gov (United States)

    John P. Pierce PhD, a professor in the Department of Family and Preventive Medicine at the University of California, San Diego and Director of Population Science at Moores Cancer Center, presented "How Do You Motivate Long-Term Behavior Change to Prevent Cancer?" 

  5. Long-term changes in organic matter of woodland soils cleared for arable cropping in Zimbabwe

    NARCIS (Netherlands)

    Zingore, S.; Manyame, C.; Nyamugafata, P.; Giller, K.E.

    2005-01-01

    Subsistence farmers in Africa depend largely on the soil organic matter to sustain crop productivity. Long-term changes in soil organic carbon and nitrogen were measured after woodland clearance for smallholder subsistence farming or for commercial farming. The contents of organic carbon and

  6. Self-guided Change: The most common form of long-term, maintained health behavior change

    Science.gov (United States)

    Bishop, F Michler

    2018-01-01

    Millions of people change risky, health-related behaviors and maintain those changes. However, they often take years to change, and their unhealthy behaviors may harm themselves and others and constitute a significant cost to society. A review—similar in nature to a scoping review—was done of the literature related to long-term health behavior change in six areas: alcohol, cocaine and heroin misuse, gambling, smoking, and overeating. Based on the limited research available, reasons for change and strategies for changing and for maintaining change were also reviewed. Fifty years of research clearly indicate that as people age, in the case of alcohol, heroin and cocaine misuse, smoking, and gambling, 80–90 percent moderate or stop their unhealthy behaviors. The one exception is overeating; only 20 percent maintain their weight loss. Most of these changes, when they occur, appear to be the result of self-guided change. More ways to accelerate self-guided, health-related behavior change need to be developed and disseminated. PMID:29375888

  7. Long-term evolution of the Campine area in Northern Belgium: past and expected future evolution of tectonics and climate

    International Nuclear Information System (INIS)

    De Craen, M.; Beerten, K.; Brassinnes, S.; Wouters, L.

    2012-01-01

    Document available in extended abstract form only. Disposal of radioactive waste in a geological repository involves the reliance, now and in the long-term future, on the geological and hydrogeological environment. In preparation of the safety and feasibility case 1 (SFC1), the long-term geodynamic evolution of Boom Clay and its geological environment in the Campine area in northern Belgium is studied. Time frames considered are the geological past and the future 1 million year. The idea is that the past long-term evolution can be extended to predict what might happen in the future. In this paper, we first focusses on the past long-term tectonic evolution of the Campine area, and make an extrapolation for the future 1 Ma. We then focus on past climate evolution, and similarly, an assessment of possible future climate conditions is made for the Campine area within the next 1 Ma. Another paper focusses on the combined effect of tectonics and climate on the evolution of the surface environment in the Campine area for the next 1 Ma, with respect to geomorphological, pedological and hydrological processes. During the Palaeozoic, the geodynamic evolution of the Campine area was mainly determined by tectonics. A large intermittently subsiding sedimentary basin existed in which large amounts of sediments were deposited, and which was protected by the Brabant Massif from major oro-genetic compressive processes. Palaeozoic sediments in the Campine Basin reach a maximum thickness of 4000 m. During Mesozoic and Cenozoic, its geodynamic evolution was the interactive result of plate tectonics, sea level changes and climate evolution. Further subsidence resulted in a thick sequence of sedimentary deposits. Mesozoic sediments are found throughout the Campine area while remains of Jurassic-Triassic sediments are found only in the central Roer Valley Graben in the east. The Cenozoic is characterised by a succession of sub-horizontal layers of Tertiary clays and sands and covered by

  8. Long term fluctuations of groundwater mine pollution in a sulfide mining district with dry Mediterranean climate: Implications for water resources management and remediation.

    Science.gov (United States)

    Caraballo, Manuel A; Macías, Francisco; Nieto, José Miguel; Ayora, Carlos

    2016-01-01

    Water resources management and restoration strategies, and subsequently ecological and human life quality, are highly influenced by the presence of short and long term cycles affecting the intensity of a targeted pollution. On this respect, a typical acid mine drainage (AMD) groundwater from a sulfide mining district with dry Mediterranean climate (Iberian Pyrite Belt, SW Spain) was studied to unravel the effect of long term weather changes in water flow rate and metal pollutants concentration. Three well differentiated polluting stages were observed and the specific geochemical, mineralogical and hydrological processes involved (pyrite and enclosing rocks dissolution, evaporitic salts precipitation-redisolution and pluviometric long term fluctuations) were discussed. Evidencing the importance of including longer background monitoring stage in AMD management and restoration strategies, the present study strongly advise a minimum 5-years period of AMD continuous monitoring previous to the design of any AMD remediation system in regions with dry Mediterranean climate. Copyright © 2015 Elsevier B.V. All rights reserved.

  9. Global variation in the long-term seasonal changes observed in ionospheric F region data

    Directory of Open Access Journals (Sweden)

    C. J. Scott

    2015-04-01

    Full Text Available Long-term variability has previously been observed in the relative magnitude of annual and semi-annual variations in the critical frequency (related to the peak electron concentration of the ionospheric F2 layer (foF2. In this paper we investigate the global patterns in such variability by calculating the time varying power ratio of semi-annual to annual components seen in ionospheric foF2 data sequences from 77 ionospheric monitoring stations around the world. The temporal variation in power ratios observed at each station was then correlated with the same parameter calculated from similar epochs for the Slough/Chilton data set (for which there exists the longest continuous sequence of ionospheric data. This technique reveals strong regional variation in the data, which bears a striking similarity to the regional variation observed in long-term changes to the height of the ionospheric F2 layer. We argue that since both the height and peak density of the ionospheric F2 region are influenced by changes to thermospheric circulation and composition, the observed long-term and regional variability can be explained by such changes. In the absence of long-term measurements of thermospheric composition, detailed modelling work is required to investigate these processes.

  10. Understanding Pan-Arctic Tundra Vegetation Change Through Long-term Remotely Sensed Data

    Science.gov (United States)

    Bhatt, U.; Walker, D. A.; Bieniek, P.; Raynolds, M. K.; Epstein, H. E.; Comiso, J. C.; Pinzon, J. E.; Tucker, C. J.

    2012-12-01

    The goal of this paper is to present an analysis of the seasonality of tundra vegetation variability and change using long-term remotely sensed data as well as ground based measurements and reanalyses. An increase of Pan-Arctic tundra vegetation greenness has been documented using the remotely sensed Normalized Difference Vegetation Index (NDVI). Coherent variability between NDVI, springtime coastal sea ice (passive microwave) and land surface temperatures (AVHRR) has also been established. Satellite based snow and cloud cover data sets are being incorporated into this analysis. The Arctic tundra is divided into domains based on Treshnikov divisions that are modified based on floristic provinces. There is notable heterogeneity in Pan-Arctic vegetation and climate trends, which necessitates a regional analysis. This study uses remotely sensed weekly 25-km sea ice concentration, weekly surface temperature, and bi-weekly NDVI from 1982 to 2010. The GIMMS NDVI3g data has been corrected for biases during the spring and fall, with special focus on the Arctic. Trends of Maximum NDVI (MaxNDVI), Time Integrated NDVI (TI-NDVI), Summer Warmth Index (SWI, sum of degree months above freezing during May-August), and open water area are calculated for the Pan Arctic. Remotely sensed snow data trends suggest varying patterns throughout the Arctic and may in part explain the heterogeneous MaxNDVI trends. Standard climate data (station, reanalysis, and model data) and ground observations are used in the analysis to provide additional support for hypothesized mechanisms. Overall, we find that trends over the 30-year record are changing as evidenced by the following examples from recent years. The sea ice decline has increased in Eurasia and slowed in North America. The weekly AVHRR landsurface temperatures reveal that there has been summer cooling over Eurasia and that the warming over North America has slowed. The MaxNDVI rates of change have diverged between N. America and Eurasia

  11. Long-term streamflow response to climatic variability in the Loess Plateau, China

    Science.gov (United States)

    Shenping Wang; Zhiqiang Zhang; Ge Sun; Steven G. McNulty; Huayong Zhang; Jianlao Li; Manliang Zhang

    2008-01-01

    The Loess Plateau region in northwestern China has experienced severe water resource shortages due to the combined impacts of climate and land use changes and water resource exploitation during the past decades. This study was designed to examine the impacts of climatic variability on streamflow characteristics of a 12-km2 watershed near Tianshui City, Gansu Province...

  12. Climate Considerations in Long-Term Safety Assessments for Nuclear Waste Repositories

    Energy Technology Data Exchange (ETDEWEB)

    Naeslund, Jens-Ove; Brandefelt, Jenny; Claesson Liljedahl, Lillemor [Svensk Kaernbraenslehantering AB, Stockholm (Sweden)], E-mail: jens-ove.naslund@skb.se

    2013-05-15

    For a deep geological repository for spent nuclear fuel planned in Sweden, the safety assessment covers up to 1 million years. Climate scenarios range from high-end global warming for the coming 100 000 years, through deep permafrost, to large ice sheets during glacial conditions. In contrast, in an existing repository for short-lived waste the activity decays to low levels within a few tens of thousands of years. The shorter assessment period, 100 000 years, requires more focus on climate development over the coming tens of thousands of years, including the earliest possibility for permafrost growth and freezing of the engineered system. The handling of climate and climate change in safety assessments must be tailor-made for each repository concept and waste type. However, due to the uncertain future climate development on these vast time scales, all safety assessments for nuclear waste repositories require a range of possible climate scenarios.

  13. Climate considerations in long-term safety assessments for nuclear waste repositories.

    Science.gov (United States)

    Näslund, Jens-Ove; Brandefelt, Jenny; Liljedahl, Lillemor Claesson

    2013-05-01

    For a deep geological repository for spent nuclear fuel planned in Sweden, the safety assessment covers up to 1 million years. Climate scenarios range from high-end global warming for the coming 100 000 years, through deep permafrost, to large ice sheets during glacial conditions. In contrast, in an existing repository for short-lived waste the activity decays to low levels within a few tens of thousands of years. The shorter assessment period, 100 000 years, requires more focus on climate development over the coming tens of thousands of years, including the earliest possibility for permafrost growth and freezing of the engineered system. The handling of climate and climate change in safety assessments must be tailor-made for each repository concept and waste type. However, due to the uncertain future climate development on these vast time scales, all safety assessments for nuclear waste repositories require a range of possible climate scenarios.

  14. The International Symposium on Space Climate (2nd), Long-Term Changes in the Sun and their Effects in the Heliosphere and Plant Earth, held in Sinaia, Romania, on 13-16 September 2006

    National Research Council Canada - National Science Library

    2008-01-01

    This report summarizes the activities and statistics for the Second International Symposium of Space Climate organized by Astronomical Institute of the Romanian Academy in Sinaia, Romania, on 13-16...

  15. Verification and accreditation schemes for climate change activities: A review of requirements for verification of greenhouse gas reductions and accreditation of verifiers—Implications for long-term carbon sequestration

    Science.gov (United States)

    Roed-Larsen, Trygve; Flach, Todd

    The purpose of this chapter is to provide a review of existing national and international requirements for verification of greenhouse gas reductions and associated accreditation of independent verifiers. The credibility of results claimed to reduce or remove anthropogenic emissions of greenhouse gases (GHG) is of utmost importance for the success of emerging schemes to reduce such emissions. Requirements include transparency, accuracy, consistency, and completeness of the GHG data. The many independent verification processes that have developed recently now make up a quite elaborate tool kit for best practices. The UN Framework Convention for Climate Change and the Kyoto Protocol specifications for project mechanisms initiated this work, but other national and international actors also work intensely with these issues. One initiative gaining wide application is that taken by the World Business Council for Sustainable Development with the World Resources Institute to develop a "GHG Protocol" to assist companies in arranging for auditable monitoring and reporting processes of their GHG activities. A set of new international standards developed by the International Organization for Standardization (ISO) provides specifications for the quantification, monitoring, and reporting of company entity and project-based activities. The ISO is also developing specifications for recognizing independent GHG verifiers. This chapter covers this background with intent of providing a common understanding of all efforts undertaken in different parts of the world to secure the reliability of GHG emission reduction and removal activities. These verification schemes may provide valuable input to current efforts of securing a comprehensive, trustworthy, and robust framework for verification activities of CO2 capture, transport, and storage.

  16. Long-term trends of phosphorus concentrations in an artificial lake: Socio-economic and climate drivers.

    Science.gov (United States)

    Vystavna, Yuliya; Hejzlar, Josef; Kopáček, Jiří

    2017-01-01

    European freshwater ecosystems have undergone significant human-induced and environmentally-driven variations in nutrient export from catchments throughout the past five decades, mainly in connection with changes in land-use, agricultural practice, waste water production and treatment, and climatic conditions. We analysed the relations among concentration of total phosphorus (TP) in the Slapy Reservoir (a middle reservoir of the Vltava River Cascade, Czechia), and socio-economic and climatic factors from 1963 to 2015. The study was based on a time series analysis, using conventional statistical tools, and the identification of breaking points, using a segmented regression. Results indicated clear long-term trends and seasonal patterns of TP, with annual average TP increasing up until 1991 and decreasing from 1992 to 2015. Trends in annual, winter and spring average TP concentrations reflected a shift in development of sewerage and sanitary infrastructure, agricultural application of fertilizers, and livestock production in the early 1990s that was associated with changes from the planned to the market economy. No trends were observed for average TP in autumn. The summer average TP has fluctuated with increased amplitude since 1991 in connection with recent climate warming, changes in thermal stratification stability, increased water flow irregularities, and short-circuiting of TP-rich inflow during high flow events. The climate-change-induced processes confound the generally declining trend in lake-water TP concentration and can result in eutrophication despite decreased phosphorus loads from the catchment. Our findings indicate the need of further reduction of phosphorus sources to meet ecological quality standards of the EU Water Framework Directive because the climate change may lead to a greater susceptibility of the aquatic ecosystem to the supply of nutrients.

  17. Do climate model predictions agree with long-term precipitation trends in the arid southwestern United States?

    Science.gov (United States)

    Elias, E.; Rango, A.; James, D.; Maxwell, C.; Anderson, J.; Abatzoglou, J. T.

    2016-12-01

    Researchers evaluating climate projections across southwestern North America observed a decreasing precipitation trend. Aridification was most pronounced in the cold (non-monsoonal) season, whereas downward trends in precipitation were smaller in the warm (monsoonal) season. In this region, based upon a multimodel mean of 20 Coupled Model Intercomparison Project 5 models using a business-as-usual (Representative Concentration Pathway 8.5) trajectory, midcentury precipitation is projected to increase slightly during the monsoonal time period (July-September; 6%) and decrease slightly during the remainder of the year (October-June; -4%). We use observed long-term (1915-2015) monthly precipitation records from 16 weather stations to investigate how well measured trends corroborate climate model predictions during the monsoonal and non-monsoonal timeframe. Running trend analysis using the Mann-Kendall test for 15 to 101 year moving windows reveals that half the stations showed significant (p≤0.1), albeit small, increasing trends based on the longest term record. Trends based on shorter-term records reveal a period of significant precipitation decline at all stations representing the 1950s drought. Trends from 1930 to 2015 reveal significant annual, monsoonal and non-monsoonal increases in precipitation (Fig 1). The 1960 to 2015 time window shows no significant precipitation trends. The more recent time window (1980 to 2015) shows a slight, but not significant, increase in monsoonal precipitation and a larger, significant decline in non-monsoonal precipitation. GCM precipitation projections are consistent with more recent trends for the region. Running trends from the most recent time window (mid-1990s to 2015) at all stations show increasing monsoonal precipitation and decreasing Oct-Jun precipitation, with significant trends at 6 of 16 stations. Running trend analysis revealed that the long-term trends were not persistent throughout the series length, but depended

  18. Long-term herbarium records reveal temperature-dependent changes in flowering phenology in the southeastern USA

    Science.gov (United States)

    Park, Isaac W.; Schwartz, Mark D.

    2015-03-01

    In recent years, a growing body of evidence has emerged indicating that the relationship between flowering phenology and climate may differ throughout various portions of the growing season. These differences have resulted in long-term changes in flowering synchrony that may alter the quantity and diversity of pollinator attention to many species, as well as altering food availability to pollenivorous and nectarivorous animal species. However, long-term multi-season records of past flowering timing have primarily focused on temperate environments. In contrast, changes in flowering phenology within humid subtropical environments such as the southeastern USA remain poorly documented. This research uses herbarium-based methods to examine changes in flowering time across 19,328 samples of spring-, summer-, and autumn-flowering plants in the southeastern USA from the years 1951 to 2009. In this study, species that flower near the onset of the growing season were found to advance under increasing mean March temperatures (-3.391 days/°C, p = 0.022). No long-term advances in early spring flowering or spring temperature were detected during this period, corroborating previous phenological assessments for the southeastern USA. However, late spring through mid-summer flowering exhibited delays in response to higher February temperatures (over 0.1.85 days/°C, p ≤ 0.041 in all cases). Thus, it appears that flowering synchrony may undergo significant restructuring in response to warming spring temperatures, even in humid subtropical environments.

  19. Target-Dependent Structural Changes Accompanying Long-Term Synaptic Facilitation in Aplysia Neurons

    Science.gov (United States)

    Glanzman, David L.; Kandel, Eric R.; Schacher, Samuel

    1990-08-01

    The mechanisms underlying structural changes that accompany learning and memory have been difficult to investigate in the intact nervous system. In order to make these changes more accessible for experimental analysis, dissociated cell culture and low-light-level video microscopy were used to examine Aplysia sensory neurons in the presence or absence of their target cells. Repeated applications of serotonin, a facilitating transmitter important in behavioral dishabituation and sensitization, produced growth of the sensory neurons that paralleled the long-term enhancement of synaptic strength. This growth required the presence of the postsynaptic motor neuron. Thus, both the structural changes and the synaptic facilitation of Aplysia sensorimotor synapses accompanying long-term behavioral sensitization can be produced in vitro by applying a single facilitating transmitter repeatedly. These structural changes depend on an interaction of the presynaptic neuron with an appropriate postsynaptic target.

  20. Ca isotopes, chemical weathering, and geomorphic controls on long-term climate

    Science.gov (United States)

    Moore, J.; Jacobson, A. D.; Holmden, C. E.; Craw, D.

    2009-12-01

    Calcium isotope geochemistry (δ44Ca) offers a unique opportunity to directly quantify proportions of riverine Ca originating from silicate versus carbonate weathering, which is essential for understanding how geomorphic processes affecting landscape evolution, such as tectonic uplift and glaciation, influence the long-term cycling of atmospheric CO2. We measured the elemental and δ44Ca chemistry of river and rock samples from the New Zealand Southern Alps. In combination with our geochemical data, we used runoff and suspended sediment fluxes to elucidate relationships between chemical weathering, mechanical erosion, and long-term climate. The S. Alps have uniform bedrock chemistry but significant tectonic and climatic gradients. West of the main topographic divide, watersheds drain schist and experience high runoff, uplift, and erosion rates. East of the main divide, watersheds drain greywacke or schist and experience lower runoff, uplift, and erosion rates. Glaciated watersheds with high erosion rates are present throughout the mountain range. Both schist and greywacke contain up to 3% metamorphic and hydrothermal calcite. Waters exhibit two-component mixing between calcite and silicate end-members when plotted as δ44Ca versus Ca/Sr. Scatter about the mixing curve is generally smaller than the analytical uncertainty of the measurements and likely reflects variability of the end-member compositions rather than fractionation. We used the mixing relationships to calculate percentages of Ca from silicate weathering. Rivers draining greywacke average 27.6% of Ca from silicate weathering with glaciated and non-glaciated watersheds yielding 41.8 and 19.5%, respectively. Rivers draining schist average 9.8% with glaciated and non-glaciated watersheds yielding 17.7 and 3.9%, respectively. Although Ca fluxes are larger west of the main divide where erosion and runoff are higher, the percentage of Ca from silicate weathering is smaller. Hence, long-term atmospheric CO2

  1. Long-Term Changes in the Distributions of Larval and Adult Fish in the Northeast U.S. Shelf Ecosystem.

    Directory of Open Access Journals (Sweden)

    Harvey J Walsh

    Full Text Available Many studies have documented long-term changes in adult marine fish distributions and linked these changes to climate change and multi-decadal climate variability. Most marine fish, however, have complex life histories with morphologically distinct stages, which use different habitats. Shifts in distribution of one stage may affect the connectivity between life stages and thereby impact population processes including spawning and recruitment. Specifically, many marine fish species have a planktonic larval stage, which lasts from weeks to months. We compared the spatial distribution and seasonal occurrence of larval fish in the Northeast U.S. Shelf Ecosystem to test whether spatial and temporal distributions changed between two decades. Two large-scale ichthyoplankton programs sampled using similar methods and spatial domain each decade. Adult distributions from a long-term bottom trawl survey over the same time period and spatial area were also analyzed using the same analytical framework to compare changes in larval and adult distributions between the two decades. Changes in spatial distribution of larvae occurred for 43% of taxa, with shifts predominately northward (i.e., along-shelf. Timing of larval occurrence shifted for 49% of the larval taxa, with shifts evenly split between occurring earlier and later in the season. Where both larvae and adults of the same species were analyzed, 48% exhibited different shifts between larval and adult stages. Overall, these results demonstrate that larval fish distributions are changing in the ecosystem. The spatial changes are largely consistent with expectations from a changing climate. The temporal changes are more complex, indicating we need a better understanding of reproductive timing of fishes in the ecosystem. These changes may impact population productivity through changes in life history connectivity and recruitment, and add to the accumulating evidence for changes in the Northeast U.S. Shelf

  2. Evaluation of outdoor human thermal sensation of local climate zones based on long-term database

    Science.gov (United States)

    Unger, János; Skarbit, Nóra; Gál, Tamás

    2018-02-01

    This study gives a comprehensive picture on the diurnal and seasonal general outdoor human thermal sensation levels in different urban quarters based on long-term (almost 3 years) data series from urban and rural areas of Szeged, Hungary. It is supplemented with a case study dealing with an extreme heat wave period which is more and more frequent in the last decades in the study area. The intra-urban comparison is based on a thermal aspect classification of the surface, namely, the local climate zone (LCZ) system, on an urban meteorological station network and on the utilization of the physiologically equivalent temperature (PET) comfort index with categories calibrated to the local population. The selected stations represent sunlit areas well inside the LCZ areas. The results show that the seasonal and annual average magnitudes of the thermal load exerted by LCZs in the afternoon and evening follow their LCZ numbers. It is perfectly in line with the LCZ concept originally concentrating only on air temperature ( T air) differences between the zones. Our results justified the subdivision of urban areas into LCZs and give significant support to the application possibilities of the LCZ concept as a broader term covering different thermal phenomena.

  3. Long-Term Climatic and Anthropogenic Impacts on Streamwater Salinity in New York State: INCA Simulations Offer Cautious Optimism.

    Science.gov (United States)

    Gutchess, Kristina; Jin, Li; Ledesma, José L J; Crossman, Jill; Kelleher, Christa; Lautz, Laura; Lu, Zunli

    2018-02-06

    The long-term application of road salts has led to a rise in surface water chloride (Cl - ) concentrations. While models have been used to assess the potential future impacts of continued deicing practices, prior approaches have not incorporated changes in climate that are projected to impact hydrogeology in the 21st century. We use an INtegrated CAtchment (INCA) model to simulate Cl - concentrations in the Tioughnioga River watershed. The model was run over a baseline period (1961-1990) and climate simulations from a range of GCMs run over three 30-year intervals (2010-2039; 2040-2069; 2070-2099). Model projections suggest that Cl - concentrations in the two river branches will continue to rise for several decades, before beginning to decline around 2040-2069, with all GCM scenarios indicating reductions in snowfall and associated salt applications over the 21st century. The delay in stream response is most likely attributed to climate change and continued contribution of Cl - from aquifers. By 2100, surface water Cl - concentrations will decrease to below 1960s values. Catchments dominated by urban lands will experience a decrease in average surface water Cl - , although moderate compared to more rural catchments.

  4. Climate Change

    Science.gov (United States)

    Climate is the average weather in a place over a period of time. Climate change is major change in temperature, rainfall, snow, ... by natural factors or by human activities. Today climate changes are occurring at an increasingly rapid rate. ...

  5. Long-term change of activity of very low-frequency earthquakes in southwest Japan

    Science.gov (United States)

    Baba, S.; Takeo, A.; Obara, K.; Kato, A.; Maeda, T.; Matsuzawa, T.

    2017-12-01

    On plate interface near seismogenic zone of megathrust earthquakes, various types of slow earthquakes were detected including non-volcanic tremors, slow slip events (SSEs) and very low-frequency earthquakes (VLFEs). VLFEs are classified into deep VLFEs, which occur in the downdip side of the seismogenic zone, and shallow VLFEs, occur in the updip side, i.e. several kilometers in depth in southwest Japan. As a member of slow earthquake family, VLFE activity is expected to be a proxy of inter-plate slipping because VLFEs have the same mechanisms as inter-plate slipping and are detected during Episodic tremor and slip (ETS). However, long-term change of the VLFE seismicity has not been well constrained compared to deep low-frequency tremor. We thus studied long-term changes in the activity of VLFEs in southwest Japan where ETS and long-term SSEs have been most intensive. We used continuous seismograms of F-net broadband seismometers operated by NIED from April 2004 to March 2017. After applying the band-pass filter with a frequency range of 0.02—0.05 Hz, we adopted the matched-filter technique in detecting VLFEs. We prepared templates by calculating synthetic waveforms for each hypocenter grid assuming typical focal mechanisms of VLFEs. The correlation coefficients between templates and continuous F-net seismograms were calculated at each grid every 1s in all components. The grid interval is 0.1 degree for both longitude and latitude. Each VLFE was detected as an event if the average of correlation coefficients exceeds the threshold. We defined the detection threshold as eight times as large as the median absolute deviation of the distribution. At grids in the Bungo channel, where long-term SSEs occurred frequently, the cumulative number of detected VLFEs increases rapidly in 2010 and 2014, which were modulated by stress loading from the long-term SSEs. At inland grids near the Bungo channel, the cumulative number increases steeply every half a year. This stepwise

  6. Changes in the skeleton after long-term treatment with retinoids

    Energy Technology Data Exchange (ETDEWEB)

    Montag, M.; Reiser, M.; Hamm, H.; Traupe, H.; Vogt, H.J.

    1988-07-01

    The synthetic retinoids, the vitamin-A-derivatives ethretinate and isotretinoin, have substantially enlarged the therapeutic arsenal in dermatology. They are primarily used in severe cases of acne and cornification disorders. In the majority of cases, long-term treatment is necessary. Certain side effects in the skeletal system can occur, e.g., osteoporosis, premature epiphyseal closure, and changes similar to DISH (diffuse idiopathic skeletal hyperostosis). We discuss the reports in the literature and our own observations in 31 patients treated at the Westphalian Wilhelms University in Muenster, as well as at the Technical University in Munich. In 3 out of 31 patients treated by retinoids on a long-term basis, skeletal changes were found radiologically as a result of the retinoid medication.

  7. Medium- and Long-term Prediction of LOD Change by the Leap-step Autoregressive Model

    Science.gov (United States)

    Wang, Qijie

    2015-08-01

    The accuracy of medium- and long-term prediction of length of day (LOD) change base on combined least-square and autoregressive (LS+AR) deteriorates gradually. Leap-step autoregressive (LSAR) model can significantly reduce the edge effect of the observation sequence. Especially, LSAR model greatly improves the resolution of signals’ low-frequency components. Therefore, it can improve the efficiency of prediction. In this work, LSAR is used to forecast the LOD change. The LOD series from EOP 08 C04 provided by IERS is modeled by both the LSAR and AR models. The results of the two models are analyzed and compared. When the prediction length is between 10-30 days, the accuracy improvement is less than 10%. When the prediction length amounts to above 30 day, the accuracy improved obviously, with the maximum being around 19%. The results show that the LSAR model has higher prediction accuracy and stability in medium- and long-term prediction.

  8. Long-term fashion forecast based on the sociological model of cyclic changes

    Directory of Open Access Journals (Sweden)

    А V Lebsak-Kleimans

    2010-09-01

    Full Text Available The concepts of social changes coined by classical sociology may be incorporated as the basis for the elaboration of social prognostication models which, in turn, may suitable for fashion forecast applied technologies development. In the framework of the given paper fashion is described as the phenomenon of collective behaviour. The principles of long-term fashion trends forecast are shown to be in line with the concepts of cyclic development.

  9. Long-term air temperature changes in a Central European sedge-grass marsh

    Czech Academy of Sciences Publication Activity Database

    Dušek, Jiří; Stellner, Stanislav; Komárek, A.

    2013-01-01

    Roč. 6, č. 2 (2013), s. 182-190 ISSN 1936-0584 R&D Projects: GA MŠk(CZ) ED1.1.00/02.0073; GA MŽP(CZ) SP/2D1/93/07 Institutional research plan: CEZ:AV0Z60870520 Keywords : Carex acuta * fen * wetland * long-term monitoring * global change Subject RIV: EH - Ecology, Behaviour Impact factor: 2.634, year: 2013

  10. Long-term correlated change between personality traits and perceived social support in middle adulthood

    OpenAIRE

    Allemand Mathias; Schaffhuser Kathrin; Martin Mike

    2015-01-01

    This study investigated long-term correlated change between personality traits and perceived social support in middle adulthood. Two measurement occasions with an 8-year time interval from the Interdisciplinary Longitudinal Study on Adult Development (ILSE) were used. The sample consisted of 346 middle-aged adults (46-50 years at T1). Four different types of perceived social support were assessed. Personality traits were assessed with the NEO-Five-Factor Inventory (NEO-FFI). Longitudinal meas...

  11. Climate-vegetation-fire interactions and their impact on long-term carbon dynamics in a boreal peatland landscape in northern Manitoba, Canada

    Science.gov (United States)

    Camill, Philip; Barry, Ann; Williams, Evie; Andreassi, Christian; Limmer, Jacob; Solick, Donald

    2009-12-01

    Climate warming may increase the size and frequency of fires in the boreal biome, possibly causing greater carbon release that amplifies warming. However, in peatlands, vegetation change may also control long-term fire and carbon accumulation, confounding simple relationships between climate, fire, and carbon accumulation. Using 17 peat cores dating to 8000 cal years B.P. from northern Manitoba, Canada, we addressed the following questions: (1) Do past climate changes correlate with shifts in peatland vegetation? (2) What is the relationship between peatland vegetation and fire severity? (3) What is the mean return interval for boreal peat fires, and how does it change across fires of different severities? (4) How does fire severity affect carbon accumulation rates? (5) Do fire and long-term carbon accumulation change directly in response to climate or indirectly though climate-driven changes in vegetation? We measured carbon accumulation rates, fire severity, and return intervals using macroscopic charcoal and changes in vegetation using macrofossils. Climate and vegetation changes covaried, with shifts from wetter fen to drier, forested bog communities during the Holocene Thermal Maximum (HTM). Fires became more severe following the shift to forested bogs, with fire severity peaking after 4000 cal years B.P. rather than during the HTM. Rising fire severity, in turn, was correlated with a significant decrease in carbon accumulation from ˜6000 to 2000 cal years B.P. The Medieval Warm Period and Little Ice Age affected vegetation composition and permafrost, further impacting fire and carbon accumulation. Our results indicate that long-term changes in fire and carbon dynamics are mediated by climate-driven changes in vegetation.

  12. Long-term environmental monitoring for assessment of change: measurement inconsistencies over time and potential solutions.

    Science.gov (United States)

    Ellingsen, Kari E; Yoccoz, Nigel G; Tveraa, Torkild; Hewitt, Judi E; Thrush, Simon F

    2017-10-30

    The importance of long-term environmental monitoring and research for detecting and understanding changes in ecosystems and human impacts on natural systems is widely acknowledged. Over the last decades, a number of critical components for successful long-term monitoring have been identified. One basic component is quality assurance/quality control protocols to ensure consistency and comparability of data. In Norway, the authorities require environmental monitoring of the impacts of the offshore petroleum industry on the Norwegian continental shelf, and in 1996, a large-scale regional environmental monitoring program was established. As a case study, we used a sub-set of data from this monitoring to explore concepts regarding best practices for long-term environmental monitoring. Specifically, we examined data from physical and chemical sediment samples and benthic macroinvertebrate assemblages from 11 stations from six sampling occasions during the period 1996-2011. Despite the established quality assessment and quality control protocols for this monitoring program, we identified several data challenges, such as missing values and outliers, discrepancies in variable and station names, changes in procedures without calibration, and different taxonomic resolution. Furthermore, we show that the use of different laboratories over time makes it difficult to draw conclusions with regard to some of the observed changes. We offer recommendations to facilitate comparison of data over time. We also present a new procedure to handle different taxonomic resolution, so valuable historical data is not discarded. These topics have a broader relevance and application than for our case study.

  13. Radiological features of osteoarticular changes in long-term (15 years) hemodialysis patients

    International Nuclear Information System (INIS)

    Orzincolo, C.; Ghedini, M.; Cardona, P.; Bedani, P.L.; Storari, A.; Scutellari, P.N.; Cavallari, L.

    1991-01-01

    Osteoarticular complications, which are characterized by osseous pain, pathologic fractures, and decreased articular mobility, represent one of the mayor problems affecting long-term (over 15 years) hemodialysis patients. These changes seem to have a multifactorial etiology; they include osteomalacia, secondary hyperparathyroidism, and dialysis-related amyloidosis. Ten patients (5 males and 5 females, mean age 55± 7 years) on long-term (over 15 years) hemodialysis were submitted to X-ray examinations of the skull, spine, shoulders, wrists, pelvis, and knees. Serum calcium, phosphorous, parathyroid hormone, alkaline phosphatase, and basal aluminium levels were also calculated. Osteopenia was demonstrated in all patients. Seven of them had alterations due to hyperparathyroidism. Six patients exhibited signs related to dialysis spondyloarthropathy; in 9 cases amyloid lesions, geodes, and erosions were present in wrists, humeral heads, or hips. One patients exhibited osteomalacic changes. Most long-terms dialysis patients presented multifactorial osteoarticular changes due to hyperparathyroidism, osteomalacia and dialysis-related amyloidosis. Clinical sympoms and decreased articular mobility appeared to be due mainly to amyloid osteoarthropathy

  14. Identification of relationships between climate indices and long-term precipitation in South Korea using ensemble empirical mode decomposition

    Science.gov (United States)

    Kim, Taereem; Shin, Ju-Young; Kim, Sunghun; Heo, Jun-Haeng

    2018-02-01

    Climate indices characterize climate systems and may identify important indicators for long-term precipitation, which are driven by climate interactions in atmosphere-ocean circulation. In this study, we investigated the climate indices that are effective indicators of long-term precipitation in South Korea, and examined their relationships based on statistical methods. Monthly total precipitation was collected from a total of 60 meteorological stations, and they were decomposed by ensemble empirical mode decomposition (EEMD) to identify the inherent oscillating patterns or cycles. Cross-correlation analysis and stepwise variable selection were employed to select the significant climate indices at each station. The climate indices that affect the monthly precipitation in South Korea were identified based on the selection frequencies of the selected indices at all stations. The NINO12 indices with four- and ten-month lags and AMO index with no lag were identified as indicators of monthly precipitation in South Korea. Moreover, they indicate meaningful physical information (e.g. periodic oscillations and long-term trend) inherent in the monthly precipitation. The NINO12 indices with four- and ten- month lags was a strong indicator representing periodic oscillations in monthly precipitation. In addition, the long-term trend of the monthly precipitation could be explained by the AMO index. A multiple linear regression model was constructed to investigate the influences of the identified climate indices on the prediction of monthly precipitation. Three identified climate indices successfully explained the monthly precipitation in the winter dry season. Compared to the monthly precipitation in coastal areas, the monthly precipitation in inland areas showed stronger correlation to the identified climate indices.

  15. Spatial and temporal distribution of long term public policy costs under uncertainty, the case of climate change; Distribution spatiale et temporelle des couts de politiques publiques sous incertitudes: theorie et pratique dans le cas de l'effet de serre

    Energy Technology Data Exchange (ETDEWEB)

    Lecocq, F

    2000-07-15

    Because of the inertia of the climate system, policy makers cannot avoid making early decisions regarding climate change in a sea of uncertainties. In this context, the very legitimacy of economic analysis to tackle such questions, and in particular the underlying equity issues (who pays for climate mitigation? when?) faces widespread skepticism. This thesis aims at demonstrating how public economy still remains a powerful tool to try and put some rationale into the debate, by checking the internal consistency of the different discourses, and by providing robust insights, if not definitive answers, into climate decisions. We use a set of compact integrated climate policy optimization models to progressively introduce, articulate, and assess numerically the prominent issues at stake. We obtain three main results. We first demonstrate that the so-called timing debate between short term and long term action cannot be reduced to a mere dispute over discount rate. Given the high uncertainties surrounding climate change indeed, the margins of freedom we pass on to future generations, and in particular the technical and institutional systems we transmit, become more important than the discount rate value. Secondly, we apply the various emission quota allocation rules proposed in the literature for the enlargement of annex B to developing economies. We show that the distributive outcome of these rules depends critically on ex ante assumptions about future economic and emission growth. Therefrom, we conclude that a careful design of the institutions surrounding the tradable permits market is a necessary condition to enhance the systems robustness. Last, on a broader perspective, this thesis illustrates the complementarity between ethics and economics: though the economist does not have per se a superior word about what is fair, his toolbox is powerful enough to show how some intuitively appealing ideas, such as a zero discount rate to take care of both present and future

  16. Effect of organisational change type and frequency on long-term sickness absence in hospitals.

    Science.gov (United States)

    Bernstrøm, Vilde H; Kjekshus, Lars Erik

    2015-09-01

    The present study was conducted to investigate how the frequency of structural change and patient care-related change is related to employees' long-term sickness absence. Although a growing body of research is investigating the potentially harmful effects of organisational change on employee health, most studies have focused on single episodes of organisational change and do not differentiate among the types and frequencies of change. National registry data were collected from 2005 and 2007. A total of 34 712 health professionals from 56 hospitals were included (76% nurses, 18% physicians and 6% other health professionals) and the data were analysed using multilevel logistic regression. The research findings reveal a significantly higher probability of long-term sickness absence among employees who experienced more frequent structural changes (OR = 1.03; CI: 1.00-1.06; P changes. A higher frequency of organisational change may lead to more sickness-related absence among employees, with the effect depending on the type of change. These findings highlight the need for managers who are contemplating or are in the process of implementing organisational change to become more aware of the potentially harmful effects of frequent organisational change on employee health. © 2014 John Wiley & Sons Ltd.

  17. Examining Long Term Climate Related Security Risks through the Use of Gaming and Scenario Planning

    Science.gov (United States)

    2016-10-24

    for example, the India player felt they had to achieve near-peer military parity with the China and Southwest Asia players before they would invest...the game scenario, we use gender neutral pronouns (e.g., they, their) throughout. 1. David King et al., Climate Change: A Risk Assessment, ed

  18. Social Memory of Short-term and Long-term Variability in the Sahelian Climate

    Science.gov (United States)

    Roderick J. McIntosh

    2006-01-01

    The 170,000 km2 interior floodplain of the Middle Niger (Mali) is a tight mosaic of alluvial and desert microenvironments. The interannual to intermillennial climate change profiles of this fluvial anomaly thrust deep into the Sahel and southern Sahara are masterpieces of abrupt phase shifts and unpredictability. Response has been of two kinds. The Office du Niger was...

  19. Continental Arcs as Both Carbon Source and Sink in Regulating Long Term Climate

    Science.gov (United States)

    Jiang, H.; Lee, C. T.

    2017-12-01

    The long-term variability of atmospheric pCO2 is determined by the balance between the rate of geologic inputs of CO­­2 (e.g., magmatic/metamorphic degassing, carbonate weathering) and the rate of carbonate precipitation driven by silicate weathering. The Late Cretaceous-Early Cenozoic was characterized by elevated atmospheric pCO2 and greenhouse climate, likely due to increased magmatic flux from mid-ocean ridges and, in particular, continental arcs. However, it has been suggested that continental arc magmatism is accompanied by rapid uplift and erosion due to magmatic/tectonic thickening of the crust, thus continental arcs likely enhance the chemical weathering flux, in turn increasing the carbon sink. To assess the contribution of continental arcs to global carbon inputs and sinks, we conducted a case study in the Cretaceous Peninsular Ranges batholith (PRB) and associated forearc basin in southern California, USA, representing one segment of the Cretaceous Cordillera arc-forearc system. Arc magmatism occurred between 170-85 Ma, peaking at 100 Ma, but erosion of the arc continues into the early Eocene, with forearc sediments representing this protracted arc unroofing. During magmatism, we estimate the CO2 degassing flux from the PRB was at least 5-25*105 mol·km-2·yr-1. By calculating the depletion of Ca and Mg in the forearc sediments relative to their arc protoliths, we estimate the silicate weathering/carbonate precipitation flux to be 106 mol·km-2·yr-1 during Late Cretaceous magmatism, decreasing to 105 mol·km-2·yr-1 by the Early Eocene. We show that during active continental arc magmatism, the CO2 degassing flux is comparable to CO2 consumption driven by silicate weathering in the arc. However, after magmatism ends, a regional imbalance arises in which the arc no longer contributes to CO2 inputs but continued silicate weathering of the arc drives carbonate precipitation such that the arc indirectly becomes CO2 sink. We propose that the development of

  20. Effect of seasonal and long-term changes in stress on sources of water to wells

    Science.gov (United States)

    Reilly, Thomas E.; Pollock, David W.

    1995-01-01

    The source of water to wells is ultimately the location where the water flowing to a well enters the boundary surface of the ground-water system . In ground-water systems that receive most of their water from areal recharge, the location of the water entering the system is at the water table . The area contributing recharge to a discharging well is the surface area that defines the location of the water entering the groundwater system. Water entering the system at the water table flows to the well and is eventually discharged from the well. Many State agencies are currently (1994) developing wellhead-protection programs. The thrust of some of these programs is to protect water supplies by determining the areas contributing recharge to water-supply wells and by specifying regulations to minimize the opportunity for contamination of the recharge water by activities at the land surface. In the analyses of ground-water flow systems, steady-state average conditions are frequently used to simplify the problem and make a solution tractable. Recharge is usually cyclic in nature, however, having seasonal cycles and longer term climatic cycles. A hypothetical system is quantitatively analyzed to show that, in many cases, these cyclic changes in the recharge rates apparently do not significantly affect the location and size of the areas contributing recharge to wells. The ratio of the mean travel time to the length of the cyclic stress period appears to indicate whether the transient effects of the cyclic stress must be explicitly represented in the analysis of contributing areas to wells. For the cases examined, if the ratio of the mean travel time to the period of the cyclic stress was much greater than one, then the transient area contributing recharge to wells was similar to the area calculated using an average steady-state condition. Noncyclic long-term transient changes in water use, however, and cyclic stresses on systems with ratios less than 1 can and do affect the

  1. Structural change of the economy, technological progress and long-term energy demand

    International Nuclear Information System (INIS)

    Klinge Jacobsen, H.

    2000-01-01

    The material included in the report is a collection of papers dealing with different issues related to the topics included in the title. Some of these papers have already either been published or presented at various conferences. Together with a general introduction, they constitute the author's PhD dissertation. The dissertation includes six papers and two shorter notes on different aspects of structural change of the economy and energy demand. Three different issues related to long-term energy demand are discussed: (1) the importance of technological change and its representation in energy-economy modelling, (2) an integration of two different modelling approaches, and (3) the effect on energy demand of structural changes exemplified by changes in the energy supply sector and in Danish trade patterns. The report highlights a few aspects of the interaction between structural economic changes and energy demand, but it does not intend to cover a wide range of issues related to these topics. In the introductory chapter some discussions and thoughts about issues not covered by the articles are brought forward. The introductory chapter includes an overview of possible relations between longterm energy demand and the economy, technical progress demography, social conditions and politics. The first two papers discuss the importance for projections of long-term energy demand of the way in which technological progress is modelled. These papers focus on energy-economy modelling. A paper dealing with two different approaches to energy demand modelling and the possible integration of these approaches in the Danish case follows next. The integrated Danish model, is then used for analysing different revenue recycling principles in relation to a CO 2 tax. The effect of subsidising biomass use is compared with recycling through corporate tax rates. Then a paper follows describing the structural change of a specific sector, namely the energy supply sector, and the implications for

  2. Intraindividual Variability and Long-Term Changes of Thermal Quantitative Sensory Testing

    DEFF Research Database (Denmark)

    Krøigård, Thomas; Sothynathan, Isaivani; Sindrup, Søren H

    2015-01-01

    Thermal threshold examinations are widely used in the clinical setting and in studies to assess the function of the peripheral sensory nervous system. Little is known about the variation from one side of the body to the other and the long-term temporal changes and variability. In this study, 134...... and foot. Bilateral stimulations resulted in relative intertrial variations ranging from 19% to 40%. There was no significant temporal change for repeated measures. Analysis of the individual measurements of each subject at baseline and at 26 weeks, however, resulted in relatively large intertrial...

  3. Breaks in MODIS time series portend vegetation change: verification using long-term data in an arid grassland ecosystem.

    Science.gov (United States)

    Browning, Dawn M; Maynard, Jonathan J; Karl, Jason W; Peters, Debra C

    2017-07-01

    Frequency and severity of extreme climatic events are forecast to increase in the 21st century. Predicting how managed ecosystems may respond to climatic extremes is intensified by uncertainty associated with knowing when, where, and how long effects of extreme events will be manifest in an ecosystem. In water-limited ecosystems with high inter-annual variability in rainfall, it is important to be able to distinguish responses that result from seasonal fluctuations in rainfall from long-term directional increases or decreases in precipitation. A tool that successfully distinguishes seasonal from directional biomass responses would allow land managers to make informed decisions about prioritizing mitigation strategies, allocating human resource monitoring efforts, and mobilizing resources to withstand extreme climatic events. We leveraged long-term observations (2000-2013) of quadrat-level plant biomass at multiple locations across a semiarid landscape in southern New Mexico to verify the use of Normalized Difference Vegetation Index (NDVI) time series derived from 250-m Moderate Resolution Imaging Spectroradiometer (MODIS) data as a proxy for changes in aboveground productivity. This period encompassed years of sustained drought (2000-2003) and record-breaking high rainfall (2006 and 2008) followed by subsequent drought years (2011 through 2013) that resulted in a restructuring of plant community composition in some locations. Our objective was to decompose vegetation patterns derived from MODIS NDVI over this period into contributions from (1) the long-term trend, (2) seasonal cycle, and (3) unexplained variance using the Breaks for Additive Season and Trend (BFAST) model. BFAST breakpoints in NDVI trend and seasonal components were verified with field-estimated biomass at 15 sites that differed in species richness, vegetation cover, and soil properties. We found that 34 of 45 breaks in NDVI trend reflected large changes in mean biomass and 16 of 19 seasonal

  4. The Natural Gas Dilemma in New England's Electricity Sector: Experts' Perspectives on Long Term Climate Issues and Policy Opportunities

    Science.gov (United States)

    Griffith, Steven

    This thesis is an interpretive analysis of experts' perspectives on the climate implications of New England's reliance on natural gas for electricity generation. Specifically, this research, conducted through interviews and literature review, examines experts' opinions on the desired role of natural gas within the regional electricity sector, alternative energy resources, and state and regional policy opportunities toward the achievement of New England's ambitious long-term greenhouse gas reduction goals. Experts expressed concern about the climate dilemma posed by a dependence on natural gas. However, interviews revealed that short-term reliability and cost considerations are paramount for many experts, and therefore a reliance on natural gas is the existing reality. To incentivize renewable generation technologies for the purposes of long-term climate stabilization, experts advocated for the expanded implementation of renewable portfolio standard, net metering, and feed-in tariff policies. More broadly, interviewees expressed the need for an array of complementary state and regional policies.

  5. Climate change and climate policy

    International Nuclear Information System (INIS)

    Alfsen, Knut H.; Kolshus, Hans H.; Torvanger, Asbjoern

    2000-08-01

    The climate issue is a great political and scientific challenge for several reasons: (1) There are many uncertain aspects of the climate problem, such as future emission of climate gases, the response of the climate system upon these gases, and the effects of climate changes. (2) It is probable, however, that anthropogenic emission of climate gases, deforestation etc. will cause noticeable climate changes in the future. This might be observed as increased frequency of extreme weather situations. This appears to be a greater threat than a gradual increase of temperature and precipitation. (3) Since the climate system is large and react only relatively slowly on changes in for instance the emission of climate gases, the climate problem can only be solved by means of long-term measures. (4) The climate changes may be irreversible. A rational short-term strategy is to ensure maximum flexibility, which can be done by ''slowing down'' (curtailing emissions) and by avoiding irreversible actions as much as possible. The long-term challenge is to develop an economically responsible alternative to the present fossil-based energy system that permits carbon-efficient technologies to compete on price with coal and unconventional oil and gas. Norway is in a special position by being a large exporter of fossil fuel and at the same time wanting to appear responsible in environmental matters. This combination may incur considerable expenses upon Norway and it is therefore important that environmental commitments like the Kyoto agreement can be honoured to the lowest possible cost. The costs can be minimized by: (1) minimizing the measure costs in Norway, (2) working to make the international quota price as low as possible, and (3) reducing the loss of petroleum income as much as possible. This report describes the earth's climate history, the forces behind climatic changes and what the prospects for the future look like. It also reviews what is being done to curtail the emission of

  6. Atmospheric carbon dioxide and the long-term control of the Earth's climate

    Directory of Open Access Journals (Sweden)

    J. H. Carver

    1995-07-01

    . Fortunately, the rates of change due to solar brightening are slow enough that Mega-climate 3 appears to pose no threat to the biosphere for the next 0.5-2 Gyear.

  7. Atmospheric carbon dioxide and the long-term control of the Earth's climate

    Directory of Open Access Journals (Sweden)

    J. H. Carver

    level which could, in time, fall below 0.5 PAL, causing serious damage to the biosphere. Fortunately, the rates of change due to solar brightening are slow enough that Mega-climate 3 appears to pose no threat to the biosphere for the next 0.5-2 Gyear.

  8. Adaptive Change Detection for Long-Term Machinery Monitoring Using Incremental Sliding-Window

    Science.gov (United States)

    Wang, Teng; Lu, Guo-Liang; Liu, Jie; Yan, Peng

    2017-11-01

    Detection of structural changes from an operational process is a major goal in machine condition monitoring. Existing methods for this purpose are mainly based on retrospective analysis, resulting in a large detection delay that limits their usages in real applications. This paper presents a new adaptive real-time change detection algorithm, an extension of the recent research by combining with an incremental sliding-window strategy, to handle the multi-change detection in long-term monitoring of machine operations. In particular, in the framework, Hilbert space embedding of distribution is used to map the original data into the Re-producing Kernel Hilbert Space (RKHS) for change detection; then, a new adaptive threshold strategy can be developed when making change decision, in which a global factor (used to control the coarse-to-fine level of detection) is introduced to replace the fixed value of threshold. Through experiments on a range of real testing data which was collected from an experimental rotating machinery system, the excellent detection performances of the algorithm for engineering applications were demonstrated. Compared with state-of-the-art methods, the proposed algorithm can be more suitable for long-term machinery condition monitoring without any manual re-calibration, thus is promising in modern industries.

  9. Long-term WWER-440 dynamics in cyclic power output changes

    International Nuclear Information System (INIS)

    Petruzela, I.

    1989-01-01

    Xenon poisoning is one of the main factors limiting the operation of a nuclear power plant with a WWER-440 reactor in the variable load mode, when long-term dynamics applies to cyclic power output changes. An analysis of the xenon poisoning linearized transfer shows that a phase shift of 180deg takes place between the summed-up reactivity change due to a power change and the reactivity change due to xenon poisoning, this for a sine-wave power change with a period of 24 hours. Thus, the requirements are minimized for the change in reactivity of the control elements, and the maximum value can be achieved of released reactivity that can be utilized before the end of the campaign. (B.S.). 6 figs., 4 tabs., 9 refs

  10. Climatic Characteristics of the Subtropical Mountainous Cloud Forest at the Yuanyang Lake Long-Term Ecological Research Site, Taiwan

    Directory of Open Access Journals (Sweden)

    I-Ling Lai

    2006-12-01

    Full Text Available To better understand the climatic characteristics in a subtropical mountainous cloud forest at the Yuanyang Lake long-term ecological research site, weather data collected from January 1994 to December 2004 were analyzed in the present study. The obvious seasonal changes in climatic factors were observed at this site. The annual mean air temperature was 12.7°C. The lowest temperature was recorded in February (monthly mean 5.9°C, and the highest one was taken in July (monthly mean 18.1°C. Winter featured light rain with a prolonged occurrence of fog, resulting in a large reduction of radiation. In summer, fog occurred once in the early morning and the other time from afternoon to evening. The latter one was associated with the wind direction changes and usually accompanied with short moderate to heavy convective rain. Consequently the photosynthetic photon flux density (PPFD was high in the morning but reduced drastically in the afternoon. Typhoons occurred in the summer had contributed to 37% of the annual rainfall, usually resulting in torrential rain events and sharp increases in the water level of this lake. As a matter of fact, perhumid environment of this site was attributed to abundant rainfall (mean annual precipitation 3396 mm and high frequency (up to 40% of foggy time. Such conditions would reduce the intensity of solar radiation and PPFD. The average annual solar radiation at the site was 2475 MJ m-2, and annual PPFD was 5713 mol m-2. The average degree of reduction of PPFD under foggy condition was up to 88%. Such climatic characteristics are suggested to constrain the growth of plants and play an important role in competition among plant species in this cloud forest. It is considered that the distinct seasonal fluctuation in environmental factors, perhumid and dim light conditions are the most distinguished characteristics of this subtropical mountainous cloud forest ecosystem.

  11. New Zealand: long-term care in a decade of change.

    Science.gov (United States)

    Ashton, T

    2000-01-01

    Long-term care in New Zealand incorporates a mix of public and private funding and provision. After a decade of structural change, the purchasing of almost all publicly funded health and social care is now the responsibility of one central agency. Services for older persons are poorly integrated, and there are problems of access to and quality of some services. Efforts are being made to address these problems. The challenge now is to ensure that this groundwork is not lost amid the turmoil of yet another round of restructuring by an enthusiastic, newly elected government.

  12. Calcium regulation in long-term changes of neuronal excitability in the hippocampal formation

    Energy Technology Data Exchange (ETDEWEB)

    Mody, I.

    1985-01-01

    The regulation of calcium (Ca/sup 2 +/) was examined during long-term changes of neuronal excitability in the mammalian CNS. The preparations under investigation included the kindling model of epilepsy, a genetic form of epilepsy and long-term potentiation (LTP) of neuronal activity. The study also includes a discussion of the possible roles of a neuron-specific calcium-binding protein (CaBP). The findings are summarized as follows: (1) CaBP was found to have an unequal distribution in various cortical areas of the rat with higher levels in ventral structures. (2) The decline in CaBP was correlated to the number of evoked afterdischarges (AD's) during kindling-induced epilepsy. (3) Marked changes in CaBP levels were also found in the brains of the epileptic strain of mice (El). The induction of seizures further decreased the levels of CaBP in the El mice, indicating a possible genetic impairment of neuronal Ca/sup 2 +/ homeostasis in the El strain. (4) The levels of total hippocampal Ca/sup 2 +/ and Zn/sup 2 +/ were measured by atomic absorption spectrophotometry in control and commissural-kindled animals. (5) To measure Ca/sup 2 +/-homeostasis, the kinetic analysis of /sup 45/Ca uptake curves was undertaken in the in vitro hippocampus. (6) The kinetic analysis of /sup 45/Ca uptake curves revealed that Ca/sup 2 +/-regulation of the hippocampus is impaired following amygdala- and commissural kindling. (7). A novel form of long-term potentiation (LTP) of neuronal activity in the CA1 region of the hippocampus is described. The findings raise the possibility that the Ca/sup 2 +/ necessary for induction of LTP may be derived from an intraneuronal storage site.

  13. Long-Term Soil Experiments: A Key to Managing Earth's Rapidly Changing Critical Zones

    Science.gov (United States)

    Richter, D., Jr.

    2014-12-01

    In a few decades, managers of Earth's Critical Zones (biota, humans, land, and water) will be challenged to double food and fiber production and diminish adverse effects of management on the wider environment. To meet these challenges, an array of scientific approaches is being used to increase understanding of Critical Zone functioning and evolution, and one amongst these approaches needs to be long-term soil field studies to move us beyond black boxing the belowground Critical Zone, i.e., to further understanding of processes driving changes in the soil environment. Long-term soil experiments (LTSEs) provide direct observations of soil change and functioning across time scales of decades, data critical for biological, biogeochemical, and environmental assessments of sustainability; for predictions of soil fertility, productivity, and soil-environment interactions; and for developing models at a wide range of temporal and spatial scales. Unfortunately, LTSEs globally are not in a good state, and they take years to mature, are vulnerable to loss, and even today remain to be fully inventoried. Of the 250 LTSEs in a web-based network, results demonstrate that soils and belowground Critical Zones are highly dynamic and responsive to human management. The objective of this study is to review the contemporary state of LTSEs and consider how they contribute to three open questions: (1) can soils sustain a doubling of food production in the coming decades without further impinging on the wider environment, (2) how do soils interact with the global C cycle, and (3) how can soil management establish greater control over nutrient cycling. While LTSEs produce significant data and perspectives for all three questions, there is on-going need and opportunity for reviews of the long-term soil-research base, for establishment of an efficiently run network of LTSEs aimed at sustainability and improving management control over C and nutrient cycling, and for research teams that

  14. Change of nuclear administrative system and long-term program for nuclear energy in Japan

    International Nuclear Information System (INIS)

    Yun, S. W.; Yang, M. H.; Jeong, H. S.

    2001-01-01

    Japanese new governmental adminstrative system was restructured and became in operation from January 1, 2001 including newly establishment of the Ministry of Cabinet. Accordingly, Japanese nuclear administrative system were also changed significantly, in order to reflect the changing policy environment and response to them more efficiently in the use and development of nuclear energy. Atomic Energy Commission, Nuclear Safety Commission administrated by Science and Technology Agency in the past, were moved to the Ministry of Cabinet, and Integrated Science and Technology Council was also newly established under the Ministry of Cabinet. And Ministry of Economy, Trade and Industry(METI) is in charge of nuclear energy policy and the Ministry of Education, Culture, Sports, Science and Technology(MEXT) is in charge of nuclear academic science consequently. At the same time, the revision work of 'Long-term Program for Research, Development and Utilization of Nuclear of Japan' established in 1994, has been carried out from 1999 in order to set up the long term based national nuclear policy towards the 21st century, and finally the results were open to the public in November 2000. Major changes of nuclear policy of Japan the will be good references in the establishing future national nuclear policy for the use and development of nuclear energy

  15. Lock-in and change: Distributed generation in Denmark in a long-term perspective

    International Nuclear Information System (INIS)

    Vleuten, Erik van der; Raven, Rob

    2006-01-01

    There is a renewed attention for distributed generation (DG) in European electricity sectors, but implementing DG is often problematic. This article studies the current relative success of DG in Denmark. We take into account not only recent drivers of change such as energy policy and green activism, but also long-term stability and change in the electricity supply sector. In particular we analyse the lock-in on centralized electricity supply, that still frustrates DG development elsewhere. We discuss three successive national electricity regimes, analysing regime lock-in and change in terms of technologies, actors, institutions and the position of DG. Our analysis shows that Danish energy policy as well as innovative activity by key actors indeed were crucial to the recent DG revival in Denmark. On the other hand, our long-term perspective shows that Danish energy policy and actor strategies were tuned to specifically Danish opportunities and barriers created during earlier regimes. These include experience with wind turbines and CHP as well as urban municipal and rural cooperative involvement. Copying the Danish energy policy model to other countries, regardless of national specific opportunities and barriers, will therefore not guarantee a similar outcome

  16. Long term mineralogical changes in salt formations due to water and brine interactions

    International Nuclear Information System (INIS)

    Herbert, H.J.; Brewitz, W.

    1996-01-01

    Four very common long term mineralogical changes in salt formations are discussed in the view of the safety considerations for underground repositories. Two of these processes, the 'Hartsalz' and 'Carnallite' dissolution were studied in two scale in situ experiments. The results are presented and compared with the results of the geochemical modelling with the computer code EQ3/6. Furthermore the reactions leading to the formation of the gypsum cap rock on the top of the Zechstein salt formations and to the polyhalitization of anhydrite are discussed. Geological field observations and mineral assemblages agree well with the results of the geochemical modelling employing the Pitzer formalism along with the Harvie, Moller and Weare database. We conclude that once the mechanisms of the chemical reactions are well understood it becomes possible to evaluate realistically whether such processes, when encountered in the repository, are still active or whether they are finished. It also becomes possible to estimate the volume changes associated with the reactions and thus the impact of these reactions on the integrity and the geomechanical stability of the salt formation. The intimate knowledge of the reaction mechanisms of the short and long term changes in the mineralogical assemblages and the associated brine chemistry is a first prerequisite for the correct evaluation of the origin of brines. Thus, it is essential for the correct assessment of the hazards which brine inflows may pose for the safety of a repository in salt formations. (authors). 8 refs., 14 figs., 8 tabs

  17. Enabling long-term oceanographic research: Changing data practices, information management strategies and informatics

    Science.gov (United States)

    Baker, Karen S.; Chandler, Cynthia L.

    2008-09-01

    Interdisciplinary global ocean science requires new ways of thinking about data and data management. With new data policies and growing technological capabilities, datasets of increasing variety and complexity are being made available digitally and data management is coming to be recognized as an integral part of scientific research. To meet the changing expectations of scientists collecting data and of data reuse by others, collaborative strategies involving diverse teams of information professionals are developing. These changes are stimulating the growth of information infrastructures that support multi-scale sampling, data repositories, and data integration. Two examples of oceanographic projects incorporating data management in partnership with science programs are discussed: the Palmer Station Long-Term Ecological Research program (Palmer LTER) and the United States Joint Global Ocean Flux Study (US JGOFS). Lessons learned from a decade of data management within these communities provide an experience base from which to develop information management strategies—short-term and long-term. Ocean Informatics provides one example of a conceptual framework for managing the complexities inherent to sharing oceanographic data. Elements are introduced that address the economies-of-scale and the complexities-of-scale pertinent to a broader vision of information management and scientific research.

  18. Automatic Threshold Determination for a Local Approach of Change Detection in Long-Term Signal Recordings

    Directory of Open Access Journals (Sweden)

    David Hewson

    2007-01-01

    Full Text Available CUSUM (cumulative sum is a well-known method that can be used to detect changes in a signal when the parameters of this signal are known. This paper presents an adaptation of the CUSUM-based change detection algorithms to long-term signal recordings where the various hypotheses contained in the signal are unknown. The starting point of the work was the dynamic cumulative sum (DCS algorithm, previously developed for application to long-term electromyography (EMG recordings. DCS has been improved in two ways. The first was a new procedure to estimate the distribution parameters to ensure the respect of the detectability property. The second was the definition of two separate, automatically determined thresholds. One of them (lower threshold acted to stop the estimation process, the other one (upper threshold was applied to the detection function. The automatic determination of the thresholds was based on the Kullback-Leibler distance which gives information about the distance between the detected segments (events. Tests on simulated data demonstrated the efficiency of these improvements of the DCS algorithm.

  19. Transformative art: art as means for long-term neurocognitive change.

    Science.gov (United States)

    Preminger, Son

    2012-01-01

    Every artwork leads to a unique experience by the observer or participant, may it be sensory, emotional, cognitive, interactive, or spiritual experience. At the neurobiological level, such experiences are manifested as activation of the corresponding neural networks. Neuroscience has demonstrated that experience, in particular repeated experience, can cause a long-term change in the involved brain circuits (experience-dependent plasticity). This review will discuss the molding and transformative aspect of arts, examining how repeated and on-going experience of arts may alter cognitive, emotional, and behavioral patterns as well as their underlying neural circuits. The application of this approach to cognitive training and neuropsychological rehabilitation methods will be addressed as well. In addition, it will be suggested that this approach to art, as a long-term transformative medium, may lead to a novel viewpoint on art and a different approach to its creation. Artists can design artworks that aspire to form, in addition to one-shot influencing experience, on-going experiences which gradually create a lasting change, possibly improving audiences' neuropsychological functions.

  20. Transformative Art:Art as Means for Long-term Neurocognitive Change

    Directory of Open Access Journals (Sweden)

    Son ePreminger

    2012-04-01

    Full Text Available Every artwork leads to a unique experience by the observer or participant, may it be sensory, emotional, cognitive, interactive or spiritual experience. At the neurobiological level, such experiences are manifested as activation of the corresponding neural networks. Neuroscience has demonstrated that experience, in particular repeated experience, can cause a long-term change in the involved brain circuits (experience-dependent plasticity. This review will discuss the molding and transformative aspect of arts, examining how repeated and on-going experience of arts may alter cognitive, emotional and behavioral patterns as well as their underlying neural circuits. The application of this approach to cognitive training and neuropsychological rehabilitation methods will be addressed as well. In addition, it will be suggested that this approach to art, as long-term transformative, may lead to a novel viewpoint on art and a different approach to its creation. Artists can design artworks that aspire to form, in addition to one-shot influencing experience, on-going experiences which gradually create a lasting change, possibly improving audiences' neuropsychological functions.

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

    Directory of Open Access Journals (Sweden)

    Sonja Kivinen

    2017-02-01

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

  2. Long Term Ground Based Precipitation Data Analysis in California's 7 Climate Divisions: Spatial and Temporal Variability

    Science.gov (United States)

    Rodriguez, L.; El-Askary, H. M.; Rakovski, C.; Allai, M.

    2015-12-01

    California is an area of diverse topography and has what many scientists call a Mediterranean climate. Various precipitation patterns exist due to El Niño Southern Oscillation (ENSO) which can cause abnormal precipitation or droughts. As temperature increases mainly due to the increase of CO2 in the atmosphere, it is rapidly changing the climate of not only California but the world. An increase in temperature is leading to droughts in certain areas as other areas are experiencing heavy rainfall/flooding. Droughts in return are providing a foundation for fires harming the ecosystem and nearby population. Various natural hazards can be induced due to the coupling effects from inconsistent precipitation patterns and vice versa. Using wavelets and ARIMA modeling, we were able to identify anomalies of high precipitation and droughts within California's 7 climate divisions using NOAA's hourly precipitation data from rain gauges and compared the results with modeled data, SOI, PDO, and AMO. The identification of anomalies can be used to compare and correct remote sensing measurements of precipitation and droughts.

  3. Global temperature definition affects achievement of long-term climate goals

    Science.gov (United States)

    Richardson, Mark; Cowtan, Kevin; Millar, Richard J.

    2018-05-01

    The Paris Agreement on climate change aims to limit ‘global average temperature’ rise to ‘well below 2 °C’ but reported temperature depends on choices about how to blend air and water temperature data, handle changes in sea ice and account for regions with missing data. Here we use CMIP5 climate model simulations to estimate how these choices affect reported warming and carbon budgets consistent with the Paris Agreement. By the 2090s, under a low-emissions scenario, modelled global near-surface air temperature rise is 15% higher (5%–95% range 6%–21%) than that estimated by an approach similar to the HadCRUT4 observational record. The difference reduces to 8% with global data coverage, or 4% with additional removal of a bias associated with changing sea-ice cover. Comparison of observational datasets with different data sources or infilling techniques supports our model results regarding incomplete coverage. From high-emission simulations, we find that a HadCRUT4 like definition means higher carbon budgets and later exceedance of temperature thresholds, relative to global near-surface air temperature. 2 °C warming is delayed by seven years on average, to 2048 (2035–2060), and CO2 emissions budget for a >50% chance of <2 °C warming increases by 67 GtC (246 GtCO2).

  4. Implications of the international reduction pledges on long-term energy system changes and costs in China and India

    International Nuclear Information System (INIS)

    Lucas, Paul L.; Shukla, P.R.; Chen, Wenying; Ruijven, Bas J. van; Dhar, Subash; Elzen, Michel G.J. den; Vuuren, Detlef P. van

    2013-01-01

    This paper analyses the impact of postponing global mitigation action on abatement costs and energy systems changes in China and India. It compares energy-system changes and mitigation costs from a global and two national energy-system models under two global emission pathways with medium likelihood of meeting the 2 °C target: a least-cost pathway and a pathway that postpones ambitious mitigation action, starting from the Copenhagen Accord pledges. Both pathways have similar 2010–2050 cumulative greenhouse gas emissions. The analysis shows that postponing mitigation action increases the lock-in in less energy efficient technologies and results in much higher cumulative mitigation costs. The models agree that carbon capture and storage (CCS) and nuclear energy are important mitigation technologies, while the shares of biofuels and other renewables vary largely over the models. Differences between India and China with respect to the timing of emission reductions and the choice of mitigation measures relate to differences in projections of rapid economic change, capital stock turnover and technological development. Furthermore, depending on the way it is implemented, climate policy could increase indoor air pollution, but it is likely to provide synergies for energy security. These relations should be taken into account when designing national climate policies. - highlights: • We analyze long-term impacts of the international pledges for China and India. • We compare a least-cost pathway with a pathway starting from the Copenhagen pledges. • Postponing mitigation action implies much higher cumulative mitigation costs. • Postponing increases fossil fuel dependence and requires deeper long-term reductions. • Countries differ mainly due to different periods of rapid economic change

  5. Carbonate-silicate cycle models of the long-term carbon cycle, carbonate accumulation in the oceans, and climate

    International Nuclear Information System (INIS)

    Caldeira, K.G.

    1991-01-01

    Several models of the long-term carbon cycle, incorporating models of the carbonate-silicate cycle, were developed and utilized to investigate issues relating to global climate and the causes and consequences of changes in calcium carbonate accumulation in the oceans. Model results indicate that the marked mid-Cretaceous (120 Ma) global warming could be explained by increased rates of release of carbon dioxide from subduction-zone metamorphism and mid-ocean-ridges, in conjunction with paleogeographic factors. Since the mid-Cretaceous, the primary setting for calcium carbonate accumulation in the oceans has shifted from shallow-water to deep-water environments. Model results suggest that this shift could have major consequences for the carbonate-silicate cycle and climate, and lead to significant increases in the flux of metamorphic carbon dioxide to the atmosphere. Increases in pelagic carbonate productivity, and decreases in tropical shallow-water area available for neritic carbonate accumulation, have both been proposed as the primary cause of this shift. Two lines of evidence developed here (one involving a statistical analysis of Tertiary carbonate-accumulation and oxygen-isotope data, and another based on modeling the carbonate-silicate cycle and ocean chemistry) suggest that a decrease in tropical shallow-water area was more important than increased pelagic productivity in explaining this shift. Model investigations of changes in ocean chemistry at the Cretaceous/Tertiary (K/T) boundary (66 Ma) indicate that variations in deep-water carbonate productivity may affect shallow-water carbonate accumulation rates through a mechanism involving surface-water carbonate-ion concentration. In the aftermath of the K/T boundary event, deep-water carbonate production and accumulation were significantly reduced as a result of the extinction of calcareous plankton

  6. Near-term technology policies for long-term climate targets--economy wide versus technology specific approaches

    International Nuclear Information System (INIS)

    Sanden, B.A.; Azar, Christian

    2005-01-01

    The aim of this paper is to offer suggestions when it comes to near-term technology policies for long-term climate targets based on some insights into the nature of technical change. We make a distinction between economy wide and technology specific policy instruments and put forward two key hypotheses: (i) Near-term carbon targets such as the Kyoto protocol can be met by economy wide price instruments (carbon taxes, or a cap-and-trade system) changing the technologies we pick from the shelf (higher energy efficiency in cars, buildings and industry, wind, biomass for heat and electricity, natural gas instead of coal, solar thermal, etc.). (ii) Technology specific policies are needed to bring new technologies to the shelf. Without these new technologies, stricter emission reduction targets may be considered impossible to meet by the government, industry and the general public, and therefore not adopted. The policies required to bring these more advanced technologies to the shelf are more complex and include increased public research and development, demonstration, niche market creation, support for networks within the new industries, standard settings and infrastructure policies (e.g., when it comes to hydrogen distribution). There is a risk that the society in its quest for cost-efficiency in meeting near-term emissions targets, becomes blindfolded when it comes to the more difficult, but equally important issue of bringing more advanced technologies to the shelf. The paper presents mechanisms that cause technology look in, how these very mechanisms can be used to get out of the current 'carbon lock-in' and the risk with premature lock-ins into new technologies that do not deliver what they currently promise. We then review certain climate policy proposals with regards to their expected technology impact, and finally we present a let-a-hundred-flowers-bloom strategy for the next couple of decades

  7. Join the Revolution: How Montessori for Aging and Dementia can Change Long-Term Care Culture.

    Science.gov (United States)

    Bourgeois, Michelle S; Brush, Jennifer; Elliot, Gail; Kelly, Anne

    2015-08-01

    Efforts to improve the quality of life of persons with dementia in long-term care through the implementation of various approaches to person-centered care have been underway for the past two decades. Studies have yielded conflicting reports evaluating the evidence for these approaches. The purpose of this article is to outline the findings of several systematic reviews of this literature, highlighting the areas of improvement needs, and to describe a new person-centered care model, DementiAbility Methods: The Montessori Way. This model focuses on the abilities, needs, interests, and strengths of the person and creating worthwhile and meaningful roles, routines, and activities for the person within a supportive physical environment. This is accomplished through gaining the commitment of the facility's leaders, training staff, and monitoring program implementation. The potential for a culture change in long-term care environments is dependent on the development and rigorous evaluation of person-centered care approaches. Thieme Medical Publishers 333 Seventh Avenue, New York, NY 10001, USA.

  8. Metamemory ratings predict long-term changes in reactivated episodic memories

    Directory of Open Access Journals (Sweden)

    Amnon eYacoby

    2015-02-01

    Full Text Available Reactivation of long-term memory can render the memory item temporarily labile, offering an opportunity to modify it via behavioral or pharmacological intervention. Declarative memory reactivation is accompanied by a metamemory ability to subjectively assess the knowledge available concerning the target item (Feeling of knowing, FOK. We set out to examine whether FOK can predict the extent of change of long-term episodic memories by post-retrieval manipulations. To this end, participants watched a short movie and immediately thereafter tested on their memory for it. A day later, they were reminded of that movie, and either immediately or one day later, were presented with a second movie. The reminder phase consisted of memory cues to which participants were asked to judge their FOK regarding the original movie. The memory performance of participants to whom new information was presented immediately after reactivating the original episode corresponded to the degree of FOK ratings upon reactivation such that the lower their FOK, the less their memory declined. In contrast, no relation was found between FOK and memory strength for those who learned new information one day after the reminder phase. Our findings suggest that the subjective accessibility of reactivated memories may determine the extent to which new information might modify those memories.

  9. Risk factors and long-term changes of non-arteritis anterior ischaemic optic neuropathy

    Directory of Open Access Journals (Sweden)

    Ying-Xin Cui

    2016-01-01

    Full Text Available AIM:To investigate the risk factors and long-term changes of non-arteritis anterior ischaemic optic neuropathy(NAION. METHODS:Three hundred and sixty cases of patients with NAION in our hospital from January 2010 to Juny 2015 were used as patients group and another 400 people undergoing health examination were used as control group. The clinical data was collected. Optical coherence tomography(OCTwas performed. RESULTS:There were significant difference on gender, history of diabetes or hypertension, arteriosclerosis history, disc area, cup area, rim area, cup/disc area ratio, horizontal cup-disc ratio, vertical cup-disc ratio, FBG and TG of two groups(PPP>0.05. CONCLUSION:Male, with diabetes, history of hypertension, arteriosclerosis history, disc area, cup area, rim area, cup/disc area ratio, horizontal cup-disc ratio, vertical cup-disc ratio, FBG and TG are independent risk factors of NAION. Long-term damage of RNFL may not aggravate.

  10. Binge-pattern alcohol exposure during puberty induces long-term changes in HPA axis reactivity.

    Directory of Open Access Journals (Sweden)

    Magdalena M Przybycien-Szymanska

    2011-04-01

    Full Text Available Adolescence is a dynamic and important period of brain development however, little is known about the long-term neurobiological consequences of alcohol consumption during puberty. Our previous studies showed that binge-pattern ethanol (EtOH treatment during pubertal development negatively dysregulated the responsiveness of the hypothalamo-pituitary-adrenal (HPA axis, as manifested by alterations in corticotrophin-releasing hormone (CRH, arginine vasopressin (AVP, and corticosterone (CORT during this time period. Thus, the primary goal of this study was to determine whether these observed changes in important central regulators of the stress response were permanent or transient. In this study, juvenile male Wistar rats were treated with a binge-pattern EtOH treatment paradigm or saline alone for 8 days. The animals were left undisturbed until adulthood when they received a second round of treatments consisting of saline alone, a single dose of EtOH, or a second binge-pattern treatment paradigm. The results showed that pubertal binge-pattern EtOH exposure induced striking long-lasting alterations of many HPA axis parameters. Overall, our data provide strong evidence that binge-pattern EtOH exposure during pubertal maturation has long-term detrimental effects for the healthy development of the HPA axis.

  11. Facilitating long-term changes in student approaches to learning science.

    Science.gov (United States)

    Buchwitz, Brian J; Beyer, Catharine H; Peterson, Jon E; Pitre, Emile; Lalic, Nevena; Sampson, Paul D; Wakimoto, Barbara T

    2012-01-01

    Undergraduates entering science curricula differ greatly in individual starting points and learning needs. The fast pace, high enrollment, and high stakes of introductory science courses, however, limit students' opportunities to self-assess and modify learning strategies. The University of Washington's Biology Fellows Program (BFP) intervenes through a 20-session, premajors course that introduces students to the rigor expected of bioscience majors and assists their development as science learners. This study uses quantitative and qualitative approaches to assess whether the 2007-2009 BFP achieved its desired short- and long-term impacts on student learning. Adjusting for differences in students' high school grade point average and Scholastic Aptitude Test scores, we found that participation in the BFP was associated with higher grades in two subsequent gateway biology courses, across multiple quarters and instructors. Two to 4 yr after participating in the program, students attributed changes in how they approached learning science to BFP participation. They reported having learned to "think like a scientist" and to value active-learning strategies and learning communities. In addition, they reported having developed a sense of belonging in bioscience communities. The achievement of long-term impacts for a short-term instructional investment suggests a practical means to prepare diverse students for the rigors of science curricula.

  12. Long-Term Changes in Pain Sensitivity in an Animal Model of Social Anxiety

    Directory of Open Access Journals (Sweden)

    Alessandra Berry

    2014-07-01

    Full Text Available Animal models with an eco-ethological relevance can help in identifying novel and reliable stress-related markers. To this end, 3-month-old C57BL/6J male mice were exposed to social defeat (SD stress for 10 days as this stressor shows good face and predictive validity for several models of human affective disorders including depression, social phobia and post-traumatic stress disorder. Social avoidance and pain threshold were assessed 24 h and 4 weeks after the end of SD stress, while corticosterone was assayed at the beginning and at the end of the stressful procedure (days 1 and 10. SD subjects were characterized by increased corticosterone levels (30 min following stress exposure, increased latency to approach the social target in the short-term as well as increased emotionality in the long-term. Moreover, an increase in nociceptive threshold (stress-induced analgesia was found both in the short-term and 4 weeks after the end of stress. These data indicate that the SD paradigm is able to induce emotional changes associated with a stressful/traumatic event. In addition, they indicate that variations in the nociceptive threshold might represent a physiological marker of both short- and long-term effects of stress.

  13. Stand structure modulates the long-term vulnerability of Pinus halepensis to climatic drought in a semiarid Mediterranean ecosystem.

    Science.gov (United States)

    Moreno-Gutiérrez, Cristina; Battipaglia, Giovanna; Cherubini, Paolo; Saurer, Matthias; Nicolás, Emilio; Contreras, Sergio; Querejeta, José Ignacio

    2012-06-01

    We investigated whether stand structure modulates the long-term physiological performance and growth of Pinus halepensis Mill. in a semiarid Mediterranean ecosystem. Tree radial growth and carbon and oxygen stable isotope composition of latewood (δ(13)C(LW) and δ(18)O(LW), respectively) from 1967 to 2007 were measured in P. halepensis trees from two sharply contrasting stand types: open woodlands with widely scattered trees versus dense afforested stands. In both stand types, tree radial growth, δ(13)C(LW) and δ(18)O(LW) were strongly correlated with annual rainfall, thus indicating that tree performance in this semiarid environment is largely determined by inter-annual changes in water availability. However, trees in dense afforested stands showed consistently higher δ(18)O(LW) and similar δ(13)C(LW) values compared with those in neighbouring open woodlands, indicating lower stomatal conductance and photosynthesis rates in the former, but little difference in water use efficiency between stand types. Trees in dense afforested stands were more water stressed and showed lower radial growth, overall suggesting greater vulnerability to drought and climate aridification compared with trees in open woodlands. In this semiarid ecosystem, the negative impacts of intense inter-tree competition for water on P. halepensis performance clearly outweigh potential benefits derived from enhanced infiltration and reduced run-off losses in dense afforested stands. © 2011 Blackwell Publishing Ltd.

  14. Drivers for successful long-term lifestyle change, the role of e-health

    DEFF Research Database (Denmark)

    Brandt, Carl Joakim; Clemensen, Jane; Nielsen, Jesper Bo

    2018-01-01

    Objectives Assisting patients in lifestyle change using collaborative e-health tools can be an efficient treatment for non-communicable diseases like diabetes, cardiovascular disease and chronic obstructive lung disease that are caused or aggravated by unhealthy living in the form of unhealthy diet......, physical inactivity or tobacco smoking. In a prospective pilot study, we tested an online collaborative e-health tool in general practice. The aim of this study was to identify drivers of importance for long-term personal lifestyle changes from a patient perspective when using a collaborative e-health tool......, including the support of peers and healthcare professionals. Setting General practice clinics in the Region of Southern Denmark. Participants 10 overweight patients who had previously successfully used a hybrid online collaborative e-health tool with both face-to-face and online consultations to lose weight...

  15. Long-term changes and spatio-temporal variability of the growing season temperature in Europe during the last Millennium

    Science.gov (United States)

    Guiot, Joel; Corona, Christophe

    2010-05-01

    A gridded reconstruction of April to September temperature was produced for Europe based on tree-rings, documentaries, pollen and ice cores. The majority of the proxy series have an annual resolution. For a better inference of long-term climate variations, they were completed by number of low resolution data (decadal or more), mostly on pollen and ice-core data. An original spectral analogue method was devised to deal with this heterogeneous dataset, and especially to preserve the long-term variations and the variability of the temperature series. It is the condition is to make pertinent the comparison of the recent climate changes to a broader context of 1400 years. The reconstruction of the April-September temperature was validated with a Jack-knife technique, and it was also compared with other spatially gridded temperature reconstructions, literature data, and glacier advance and retreat curves. We also attempted to relate the spatial distribution of European temperature anomalies to known solar and volcanic forcings. We found that (1) our results are sound back to A.D. 750; (2) conditions during the last decade have exceeded all those known during the last millennium; (3) before the 20th century, cold periods can partly be explained by low solar activity and/or high volcanic activity and that Medieval Warm Period (MWP) is consistent with a high solar activity; (4) during the 20th century, however only anthropogenic forcing can explain the exceptionally high temperature rise; (5) based on an analysis of the distribution of extreme temperatures, the maximum event of the Medieval Period (1.1°C higher than the 1960-1990 reference period) had a return period of more than 1000 years, but this recently fell to less than 26 years; (6) all decades before AD 1350 were warm on average but relatively heterogeneous, while the last decade was homogeneously warmer. These results support the fact that we are facing an unprecedented changing climate in Europe unlike any known

  16. Climate Change and Roads

    DEFF Research Database (Denmark)

    Chinowsky, P.; Arndt, Channing

    2012-01-01

    to estimate the impact of individual climate stressors on road infrastructure in Mozambique. Through these models, stressor–response functions are introduced that quantify the cost impact of a specific stressor based on the intensity of the stressor and the type of infrastructure it is affecting. Utilizing...... four climate projection scenarios, the paper details how climate change response decisions may cost the Mozambican government in terms of maintenance costs and long-term roadstock inventory reduction. Through this approach the paper details how a 14% reduction in inventory loss can be achieved through...

  17. Long-term habitat changes in a protected area: Implications for herpetofauna habitat management and restoration.

    Science.gov (United States)

    Markle, Chantel E; Chow-Fraser, Gillian; Chow-Fraser, Patricia

    2018-01-01

    Point Pelee National Park, located at the southern-most tip of Canada's mainland, historically supported a large number of herpetofauna species; however, despite nearly a century of protection, six snake and five amphibian species have disappeared, and remaining species-at-risk populations are thought to be in decline. We hypothesized that long-term changes in availability and distribution of critical habitat types may have contributed to the disappearance of herpetofauna. To track habitat changes we used aerial image data spanning 85 years (1931-2015) and manually digitized and classified image data using a standardized framework. Change-detection analyses were used to evaluate the relative importance of proportionate loss and fragmentation of 17 habitat types. Marsh habitat diversity and aquatic connectivity has declined since 1931. The marsh matrix transitioned from a graminoid and forb shallow marsh interspersed with water to a cattail dominated marsh, altering critical breeding, foraging, and overwintering habitat. Reduced diversity of marsh habitats appears to be linked to the expansion of invasive Phragmites australis, which invaded prior to 2000. Loss of open habitats such as savanna and meadow has reduced availability of high quality thermoregulation habitat for reptiles. Restoration of the northwestern region and tip of Point Pelee National Park to a mixed landscape of shallow wetlands (cattail, graminoid, forb, open water) and eradication of dense Phragmites stands should improve habitat diversity. Our results suggest that long-term landscape changes resulting from habitat succession and invasive species can negatively affect habitat suitability for herpetofauna and protection of land alone does not necessarily equate to protection of sensitive herpetofauna.

  18. Long-term habitat changes in a protected area: Implications for herpetofauna habitat management and restoration.

    Directory of Open Access Journals (Sweden)

    Chantel E Markle

    Full Text Available Point Pelee National Park, located at the southern-most tip of Canada's mainland, historically supported a large number of herpetofauna species; however, despite nearly a century of protection, six snake and five amphibian species have disappeared, and remaining species-at-risk populations are thought to be in decline. We hypothesized that long-term changes in availability and distribution of critical habitat types may have contributed to the disappearance of herpetofauna. To track habitat changes we used aerial image data spanning 85 years (1931-2015 and manually digitized and classified image data using a standardized framework. Change-detection analyses were used to evaluate the relative importance of proportionate loss and fragmentation of 17 habitat types. Marsh habitat diversity and aquatic connectivity has declined since 1931. The marsh matrix transitioned from a graminoid and forb shallow marsh interspersed with water to a cattail dominated marsh, altering critical breeding, foraging, and overwintering habitat. Reduced diversity of marsh habitats appears to be linked to the expansion of invasive Phragmites australis, which invaded prior to 2000. Loss of open habitats such as savanna and meadow has reduced availability of high quality thermoregulation habitat for reptiles. Restoration of the northwestern region and tip of Point Pelee National Park to a mixed landscape of shallow wetlands (cattail, graminoid, forb, open water and eradication of dense Phragmites stands should improve habitat diversity. Our results suggest that long-term landscape changes resulting from habitat succession and invasive species can negatively affect habitat suitability for herpetofauna and protection of land alone does not necessarily equate to protection of sensitive herpetofauna.

  19. ClimaDat: A long-term network to study at different scales climatic processes and interactions between climatic compartments

    Science.gov (United States)

    Morgui, Josep Anton; Agueda, Alba; Batet, Oscar; Curcoll, Roger; Ealo, Marina; Grossi, Claudia; Occhipinti, Paola; Sánchez-García, Laura; Arias, Rosa; Rodó, Xavi

    2013-04-01

    ClimaDat (www.climadat.es) is a pioneer project of the Institut Català de Ciències del Clima (IC3) in collaboration with and funded by "la Caixa" Foundation. This project aims at studying the interactions between climate and ecosystems at different spatial and temporal scales. The ClimaDat project consists of a network of eight long-term observatory stations distributed over Spain, installed at natural and remote areas, and covering different climatic domains (e.g. Mediterranean, Atlantic, subtropics) and natural systems (e.g. delta, karsts, high mountain areas). Data obtained in the ClimaDat network will help us to understand how ecosystems are influenced by and eventually might feedback different processes in the climate system. The point of focus of these studies will be taken into account regional-and-local conditions to understand climatic global scale eventsThe data gathered will be used to study the behavior of the global element cycles and associated greenhouse gas emissions. The network is expected to offer near real-time (NRT) data free for the scientific community. Instrumentation installed at these stations mainly consists of: CO2, CH4, H2O, CO, N2O, SF6 and 222Rn analyzers, isotopic CO2, CH4 and H2O analyzers, meteorological sensors, eddy covariance equipment, four-component radiometers, soil moisture and temperature sensors, and sap flow meters. Each station may have a more focused subset of all this equipment, depending on the specific characteristics of the site. Instrumentation selected for this network has been chosen to comply with standards established in international research infrastructure projects, such as ICOS (http://www.icos-infrastructure.eu/home) or InGOS (http://www.ingos-infrastructure.eu/). Preliminary data time-series of greenhouse gases concentrations and meteorological variables are presented in this study for three currently operational ClimaDat stations: the Natural Park of the Ebre Delta (lat 40.75° N - long 0.79° E), the

  20. Hair and Nail Changes During Long-term Therapy With Ibrutinib for Chronic Lymphocytic Leukemia.

    Science.gov (United States)

    Bitar, Carole; Farooqui, Mohammed Z H; Valdez, Janet; Saba, Nakhle S; Soto, Susan; Bray, Amanda; Marti, Gerald; Wiestner, Adrian; Cowen, Edward W

    2016-06-01

    Ibrutinib, a Bruton tyrosine kinase inhibitor, is a new targeted agent approved by the US Food and Drug Administration for the treatment of chronic lymphocytic leukemia (CLL), mantle cell lymphoma, and Waldenström macroglobulinemia. Ibrutinib is overall well tolerated but long-term treatment is required until disease progression or intolerable toxic effects occur. Little is known regarding its cutaneous adverse effects. To describe the hair and nail manifestations associated with the long-term use of ibrutinib for the treatment of CLL. Prospective study of 66 patients with CLL enrolled in a single-arm phase 2 clinical trial of ibrutinib for CLL between March 2014 and October 2015 at the National Institutes of Health. The primary outcome, nail and hair changes associated with ibrutinib therapy, was assessed by an 11-question survey. In addition, the severity of nail changes was determined from a 0 to 3 rating scale for both onychoschizia and onychorrhexis. Among 66 patients (43 men and 23 women with ages ranging from 55 to 85 years), 44 (67%) reported brittle fingernails at a median of 6.5 (95% CI, 6-12) months after starting ibrutinib therapy. Fifteen patients (23%) developed brittle toenails after a median of 9 (95% CI, 6-15) months of ibrutinib therapy. Textural hair changes were reported in 17 patients (26%), at a median of 9 (95% CI, 6-12) months of ibrutinib treatment. Hair and nail abnormalities are commonly associated with ibrutinib and appear several months after initiating therapy. Ibrutinib inhibits Bruton tyrosine kinase by covalently binding to cysteine 481. Whether ibrutinib affects the hair and nails by binding and altering cysteine-rich proteins of hair and nails or by means of another mechanism remains unknown. clinicaltrials.gov Identifier: NCT01500733.

  1. Long-Term Developmental Changes in Children's Lower-Order Big Five Personality Facets.

    Science.gov (United States)

    de Haan, Amaranta; De Pauw, Sarah; van den Akker, Alithe; Deković, Maja; Prinzie, Peter

    2017-10-01

    This study examined long-term developmental changes in mother-rated lower-order facets of children's Big Five dimensions. Two independent community samples covering early childhood (2-4.5 years; N = 365, 39% girls) and middle childhood to the end of middle adolescence (6-17 years; N = 579, 50% girls) were used. All children had the Belgian nationality. Developmental changes were examined using cohort-sequential latent growth modeling on the 18 facets of the Hierarchical Personality Inventory for Children. In early childhood, changes were mostly similar across child gender. Between 2 and 4.5 years, several facets showed mean-level stability; others changed in the direction of less Extraversion and Emotional Stability, and more Benevolence and Imagination. The lower-order facets of Conscientiousness showed opposite changes. Gender differences became more apparent from middle childhood onward for facets of all dimensions except Imagination, for which no gender differences were found. Between 6 and 17 years, same-dimension facets showed different shapes of growth. Facets that changed linearly changed mostly in the direction of less Extraversion, Benevolence, Conscientiousness, Emotional Stability, and Imagination. Changes in facets for which nonlinear growth was found generally moved in direction or magnitude during developmental transitions. This study provides comprehensive, fine-grained knowledge about personality development during the first two decades of life. © 2016 Wiley Periodicals, Inc.

  2. Initial Analyses of Change Detection Capabilities and Data Redundancies in the Long Term Resource Monitoring Program

    National Research Council Canada - National Science Library

    Lubinski, Kenneth

    2001-01-01

    Evaluations of Long Term Resource Monitoring Program sampling designs for water quality, fish, aquatic vegetation, and macroinvertebrates were initiated in 1999 by analyzing data collected since 1992...

  3. Assessment of long-term channel changes in the Mekong River using remote sensing and a channel-evolution model

    Science.gov (United States)

    Miyazawa, N.

    2011-12-01

    River-channel changes are a key factor affecting physical, ecological and management issues in the fluvial environment. In this study, long-term channel changes in the Mekong River were assessed using remote sensing and a channel-evolution model. A channel-evolution model for calculating long-term channel changes of a measndering river was developed using a previous fluid-dynamic model [Zolezzi and Seminara, 2001], and was applied in order to quantify channel changes of two meandering reaches in the Mekong River. Quite few attempts have been made so far to combine remote sensing observation of meandering planform change with the application of channel evolution models within relatively small-scale gravel-bed systems in humid temperate regions. The novel point of the present work is to link state-of-art meandering planform evolution model with observed morphological changes within large-scale sand-bed rivers with higher bank height in tropical monsoonal climate regions, which are the highly dynamic system, and assess the performance. Unstable extents of the reaches could be historically identified using remote-sensing technique. The instability caused i) bank erosion and accretion of meander bends and ii) movement or development of bars and changes in the flow around the bars. The remote sensing measurements indicate that maximum erosion occurred downstream of the maximum curvature of the river-center line in both reaches. The model simulations indicates that under the mean annual peak discharge the maximum of excess longitudinal velocity near the banks occurs downstream of the maximum curvature in both reaches. The channel migration coefficients of the reaches were calibrated by comparing remote-sensing measurements and model simulations. The diffrence in the migration coefficients between both reaches depends on the diffrence in bank height rather than the geotechnical properties of floodplain sediments. Possible eroded floodplain areas and accreted floodplain

  4. Nonparametric Monitoring for Geotechnical Structures Subject to Long-Term Environmental Change

    Directory of Open Access Journals (Sweden)

    Hae-Bum Yun

    2011-01-01

    Full Text Available A nonparametric, data-driven methodology of monitoring for geotechnical structures subject to long-term environmental change is discussed. Avoiding physical assumptions or excessive simplification of the monitored structures, the nonparametric monitoring methodology presented in this paper provides reliable performance-related information particularly when the collection of sensor data is limited. For the validation of the nonparametric methodology, a field case study was performed using a full-scale retaining wall, which had been monitored for three years using three tilt gauges. Using the very limited sensor data, it is demonstrated that important performance-related information, such as drainage performance and sensor damage, could be disentangled from significant daily, seasonal and multiyear environmental variations. Extensive literature review on recent developments of parametric and nonparametric data processing techniques for geotechnical applications is also presented.

  5. Long-term athlete development Canada: attempting system change and multi-agency cooperation.

    Science.gov (United States)

    Norris, Stephen R

    2010-01-01

    This text provides a synopsis, as well as some greater detail, concerning the "Canadian Sport for Life" project Long-Term Athlete Development Canada (LTAD) initiated in 2004. The genesis of the project may be found in the Canadian Sport Policy released in 2002 by Sport Canada, the sport participation and performance agency within the Canadian Heritage Ministry of the Canadian Government. The project has grown from relatively humble beginnings to become a system-wide movement and catalyst for change that encompasses not only sport participation and excellence, but also aspects to do with education, health, and general recreation. Additionally, it involves all age groups (cradle to grave). Although the project was initiated on behalf of performance sport, it is a clear example of how sport can influence and interact with many facets of a society. In Canada, LTAD clearly is tied to a philosophy that spans a broad narrative from healthy active lives to elite sport performance.

  6. The stability of vacuum phototriodes to varying light pulse loads and long term changes in response.

    CERN Document Server

    Hobson, Peter

    2012-01-01

    Mesh anode Vacuum Phototriodes (VPTs) are radiation resistant, single gain-stage photomultipliers which are designed to operate in a strong quasi-axial magnetic field. These VPTs are used in the endcap electromagnetic calorimeter of the CMS experiment at the CERN LHC to detect scintillation light from lead tungstate crystals. Short term dynamic response changes occur because of pulse rate variations during normal LHC operation cycles. Over the longer term the effect of increasing integrated charge taken from the photocathode causes an overall degradation of response. We have investigated these effects over time periods exceeding two years of simulated operation and discuss the implications for the long term performance of the VPTs in CMS.

  7. Long-term changes in cell population kinetics of skin tissue after local beta-irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Yamaguchi, T [National Inst. of Radiological Sciences, Chiba (Japan)

    1975-06-01

    Using /sup 3/H-thymidine autoradiography, long-term alterations in cell kinetics were studied in guinea pig skin after ..beta..irradiation with 3000 rads. After complete depopulation, epidermal basal cells at the radiation margin became proliferative 10 days postirradiation and spread over the depopulated area. When epithelization (20 days) was complete the cell cycle time of the basal cells reverted to normal, but the differentiation rate was much slower than that in unirradiated skin. This appeared to be a cause of the persistent (acanthotic) hyperplasia. Similar but slower changes were found in dermal tissue. Reparative proliferation of fibroblasts and capillary endothelial cells began at 20 and 30 days, respectively. Active fibroblastic proliferation was found as late as 110 days. This, along with the abortive nature of the reparative angiogenesis, seemed to be a cause of the later fibrosis (150 to 400 days).

  8. Climate change

    International Nuclear Information System (INIS)

    Anon.

    1990-01-01

    In this paper, the authors discuss in brief the magnitude and rate of past changes in climate and examine the various factors influencing climate in order to place the potential warming due to increasing greenhouse gas concentrations in context. Feedback mechanisms that can amplify or lessen imposed climate changes are discussed next. The overall sensitivity of climate to changes in forcing is then considered, followed by a discussion of the time-dependent response of the Earth system. The focus is on global temperature as an indicator for the magnitude of climatic change

  9. Long-Term Memory: A Natural Mechanism for the Clustering of Extreme Events and Anomalous Residual Times in Climate Records

    Science.gov (United States)

    Bunde, Armin; Eichner, Jan F.; Kantelhardt, Jan W.; Havlin, Shlomo

    2005-01-01

    We study the statistics of the return intervals between extreme events above a certain threshold in long-term persistent records. We find that the long-term memory leads (i)to a stretched exponential distribution of the return intervals, (ii)to a pronounced clustering of extreme events, and (iii)to an anomalous behavior of the mean residual time to the next event that depends on the history and increases with the elapsed time in a counterintuitive way. We present an analytical scaling approach and demonstrate that all these features can be seen in long climate records. The phenomena should also occur in heartbeat records, Internet traffic, and stock market volatility and have to be taken into account for an efficient risk evaluation.

  10. Pulmonary function changes in long-term survivors of bone marrow transplantation

    International Nuclear Information System (INIS)

    Gore, Elizabeth M.; Lawton, Colleen A.; Ash, Robert C.; Lipchik, Randolph J.

    1996-01-01

    Purpose: This study was undertaken to evaluate long-term pulmonary function changes in patients undergoing bone marrow transplantation (BMT), to assess their clinical significance, and to identify factors influencing these changes. Methods and Materials: Pulmonary function tests (PFT) were evaluated before and after BMT in 111 adult patients undergoing BMT between 1985 and 1991. Forced expiratory volume at 1 s (FEV 1 ), forced vital capacity (FVC), diffusing capacity (DLCO), and total lung capacity (TLC) were evaluated. One hundred and three patients (92.8%) received total body irradiation (TBI) to a total dose of 14 Gy in nine equal fractions. The lung dose was restricted to 1 , FVC, and TLC were lower than pre transplant values (p 1 did not fall significantly in patients without acute or chronic GVHD and recovered earlier than in patients without post transplant pulmonary infection. Recovery of FVC, TLC, and DLCO was also delayed in patients with acute and chronic GVHD and post transplant pulmonary infection. Multiple regression analysis revealed an association between a higher radiation dose to the lungs, and decreased FVC at 2 years (p = 0.01). Progressive obstructive pulmonary disease was not observed. Conclusions: An initial decline in PFTs with subsequent recovery was observed. Factors associated with delayed recovery and incomplete recovery of PFTs were GVHD, post transplant pulmonary infection, and higher radiation dose to the lungs. The conditioning regimen used at Medical College of Wisconsin, including relatively high TBI doses with partial transmission pulmonary shielding, appears to be well tolerated by the lungs in long-term survivors. No progressive decline in PFTs or symptomatic decline in pulmonary function was observed during the time interval studied

  11. Enabling Long-Term Earth Science Research: Changing Data Practices (Invited)

    Science.gov (United States)

    Baker, K. S.

    2013-12-01

    Data stewardship plans are shaped by our shared experiences. As a result, community engagement and collaborative activities are central to the stewardship of data. Since modes and mechanisms of engagement have changed, we benefit from asking anew: ';Who are the communities?' and ';What are the lessons learned?'. Data stewardship with its long-term care perspective, is enriched by reflection on community experience. This presentation draws on data management issues and strategies originating from within long-term research communities as well as on recent studies informed by library and information science. Ethnographic case studies that capture project activities and histories are presented as resources for comparative analysis. Agency requirements and funding opportunities are stimulating collaborative endeavors focused on data re-use and archiving. Research groups including earth scientists, information professionals, and data systems designers are recognizing the possibilities for new ways of thinking about data in the digital arena. Together, these groups are re-conceptualizing and reconfiguring for data management and data curation. A differentiation between managing data for local use and production of data for re-use remotely in locations and fields remote from the data origin is just one example of the concepts emerging to facilitate development of data management. While earth scientists as data generators have the responsibility to plan new workflows and documentation practices, data and information specialists have responsibility to promote best practices as well as to facilitate the development of community resources such as controlled vocabularies and data dictionaries. With data-centric activities and changing data practices, the potential for creating dynamic community information environments in conjunction with development of data facilities exists but remains elusive.

  12. Global observed long-term changes in temperature and precipitation extremes: A review of progress and limitations in IPCC assessments and beyond

    OpenAIRE

    Lisa V. Alexander

    2016-01-01

    The Intergovernmental Panel on Climate Change (IPCC) first attempted a global assessment of long-term changes in temperature and precipitation extremes in its Third Assessment Report in 2001. While data quality and coverage were limited, the report still concluded that heavy precipitation events had increased and that there had been, very likely, a reduction in the frequency of extreme low temperatures and increases in the frequency of extreme high temperatures. That overall assessment had ch...

  13. Ramifications of a potential gap in passive microwave data for the long-term sea ice climate record

    Science.gov (United States)

    Meier, W.; Stewart, J. S.

    2017-12-01

    will also discuss potential contingency plans, such as using operational sea ice charts, to fill any gaps. This would allow the record to continue, but the consistency of the time series will be degraded because the ice charts use human analysis and differing sources, amounts and quality of input data, which makes them sub-optimal for long-term climate records.

  14. Modeling long-term changes in forested landscapes and their relation to the Earth's energy balance

    Science.gov (United States)

    Shugart, H. H.; Emanuel, W. R.; Solomon, A. M.

    1984-01-01

    The dynamics of the forested parts of the Earth's surface on time scales from decades to centuries are discussed. A set of computer models developed at Oak Ridge National Laboratory and elsewhere are applied as tools. These models simulate a landscape by duplicating the dynamics of growth, death and birth of each tree living on a 0.10 ha element of the landscape. This spatial unit is generally referred to as a gap in the case of the forest models. The models were tested against and applied to a diverse array of forests and appear to provide a reasonable representation for investigating forest-cover dynamics. Because of the climate linkage, one important test is the reconstruction of paleo-landscapes. Detailed reconstructions of changes in vegetation in response to changes in climate are crucial to understanding the association of the Earth's vegetation and climate and the response of the vegetation to climate change.

  15. Biochemical Changes in Erythrocytes as a Molecular Marker of Cell Damage during Long-Term Simvastatin Treatment.

    Science.gov (United States)

    Mikashinovich, Z I; Belousova, E S

    2016-08-01

    Long-term administration of simvastatin to rats, irrespective of the baseline cholesterol levels, induced biochemical changes in erythrocytes attesting to hypoxic damage (accumulation of lactate and 2,3-diphosphoglycerate), disturbances in ATP-dependent mechanisms of ion homeostasis regulation (decrease in total ATPase and Ca(2+)-ATPase activities), and antioxidant enzymes system imbalance. These changes can be considered as a sensitive indicator and molecular basis of cell damage during long-term administration of statins.

  16. Long-term correlated change between personality traits and perceived social support in middle adulthood.

    Science.gov (United States)

    Allemand, Mathias; Schaffhuser, Kathrin; Martin, Mike

    2015-03-01

    This study investigated long-term correlated change between personality traits and perceived social support in middle adulthood. Two measurement occasions with an 8-year time interval from the Interdisciplinary Longitudinal Study on Adult Development (ILSE) were used. The sample consisted of 346 middle-aged adults (46-50 years at T1). Four different types of perceived social support were assessed. Personality traits were assessed with the NEO-Five-Factor Inventory (NEO-FFI). Longitudinal measurement invariance (MI) was established for both measures. The mean rank-order stabilities were .79 and .62 for personality traits and for perceived social support, respectively. The results demonstrated a mean-level increase for neuroticism and a decrease for extraversion and significant change variances for all constructs. The results of latent change models showed significant initial level correlations and correlated changes between personality traits and social support, implying that changes in these constructs show commonality. The results can expand our current thinking about correlated change in personality. © 2015 by the Society for Personality and Social Psychology, Inc.

  17. Climate-vegetation-soil interactions and long-term hydrologic partitioning: signatures of catchment co-evolution

    Directory of Open Access Journals (Sweden)

    P. A. Troch

    2013-06-01

    Full Text Available Budyko (1974 postulated that long-term catchment water balance is controlled to first order by the available water and energy. This leads to the interesting question of how do landscape characteristics (soils, geology, vegetation and climate properties (precipitation, potential evaporation, number of wet and dry days interact at the catchment scale to produce such a simple and predictable outcome of hydrological partitioning? Here we use a physically-based hydrologic model separately parameterized in 12 US catchments across a climate gradient to decouple the impact of climate and landscape properties to gain insight into the role of climate-vegetation-soil interactions in long-term hydrologic partitioning. The 12 catchment models (with different paramterizations are subjected to the 12 different climate forcings, resulting in 144 10 yr model simulations. The results are analyzed per catchment (one catchment model subjected to 12 climates and per climate (one climate filtered by 12 different model parameterization, and compared to water balance predictions based on Budyko's hypothesis (E/P = ϕ (Ep/P; E: evaporation, P: precipitation, Ep: potential evaporation. We find significant anti-correlation between average deviations of the evaporation index (E/P computed per catchment vs. per climate, compared to that predicted by Budyko. Catchments that on average produce more E/P have developed in climates that on average produce less E/P, when compared to Budyko's prediction. Water and energy seasonality could not explain these observations, confirming previous results reported by Potter et al. (2005. Next, we analyze which model (i.e., landscape filter characteristics explain the catchment's tendency to produce more or less E/P. We find that the time scale that controls subsurface storage release explains the observed trend. This time scale combines several geomorphologic and hydraulic soil properties. Catchments with relatively longer

  18. Computer Simulations of Developmental Change: The Contributions of Working Memory Capacity and Long-Term Knowledge

    Science.gov (United States)

    Jones, Gary; Gobet, Fernand; Pine, Julian M.

    2008-01-01

    Increasing working memory (WM) capacity is often cited as a major influence on children's development and yet WM capacity is difficult to examine independently of long-term knowledge. A computational model of children's nonword repetition (NWR) performance is presented that independently manipulates long-term knowledge and WM capacity to determine…

  19. The impact of long-term changes in water table height on carbon cycling in sub-boreal peatlands

    Science.gov (United States)

    Pypker, T. G.; Moore, P. A.; Waddington, J. M.; Hribljan, J. A.; Ballantyne, D.; Chimner, R. A.

    2011-12-01

    Peatlands are a critical component in the global carbon (C) cycle because they have been slowly sequestering atmospheric greenhouse gases as peat since the last glaciation. Today, soil C stocks in peatlands are estimated to represent 224 to 455 Pg, equal to 12-30% of the global soil C pool. At present, peatlands are estimated to sequester 76 Tg C yr-1. The flux of C to and from peatlands is likely to respond to climate change, thereby influencing atmospheric C concentrations. Peatland C budgets are tightly linked to their hydrology, hence, it is critical we understand how changes in hydrology will affect the C budgets of peatlands. The main objective of the project was to determine how long-term changes in water table height affect CO2 and CH4 fluxes from three adjacent peatlands. This study took place in the Seney National Wildlife Refuge (SNWR) in the Upper Peninsula of Michigan. SNWR is home to the largest wetland drainage project in Michigan. In 1912, ditches and dikes were created in an effort to convert approximately 20,000 ha of peatland to agriculture. The ditches and dikes were unsuccessful in creating agricultural land, but they are still in place. The manipulation of water table heights provides an opportunity to research how long-term peat drying or wetting alters C cycling in peatlands. From May to November in 2009, 2010 and 2011, we monitored CO2 fluxes using eddy covariance and chamber techniques in three adjacent peatlands with lowered, relatively unaltered ("control") and raised water table heights. In 2011, we installed CH4 analyzers to continuously monitor CH4 fluxes at the sites with high and relatively unaltered water table heights. The results are compared across sites to determine how changes in water table height might affect C fluxes sub-boreal peatlands.

  20. Boundary Organizations: Creating a Unique Model for Sustained Dialog Among Scientists and Decison Makers About Long-term Change

    Science.gov (United States)

    Duncan, B.; Carter, H.; Knight, E.; Meyer, R.

    2015-12-01

    California Ocean Science Trust is a boundary organization formed by the state of California. We work across traditional boundaries between government, science, and communities to build trust and understanding in ocean and coastal science. We work closely with decision makers to understand their priority needs and identify opportunities for science to have a meaningful impact, and we engage scientists and other experts to compile and translate information into innovative products that help to meet those needs. This often sparks new collaborations that live well beyond the products themselves. Through this unique model, we are deepening relationships and facilitating an ongoing dialogue between scientists, decision-makers, and communities. The West Coast of the United States is already experiencing climate-driven changes in marine conditions at both large and small spatial scales. Decision makers are increasingly concerned with the potential threats that these changes pose to coastal communities, industries, ecosystems, and species. Detecting and understanding these multi-stressor changes requires consideration across scientific disciplines and management jurisdictions. Research and monitoring programs must reflect this new reality: they should be designed to connect with the decision makers who may use their results. In this presentation, I will share how we are drawing from the West Coast Ocean Acidification and Hypoxia Science Panel - an interdisciplinary team of scientists convened by Ocean Science Trust from California, Oregon, Washington, and British Columbia - to develop actionable guidance for long-term monitoring for long-term change. Building on our experiences working with the Panel, I will discuss the unique model that boundary organizations provide for sustained dialog across traditionally siloed disciplines and management regimes, and share best practices and lessons learned in working across those boundaries.

  1. Sustainable Change Sequence: a framework for developing behavior change interventions for patients with long-term conditions

    OpenAIRE

    Elwyn, Glyn; Marrin, Katy; Frosch, Dominick; White, James

    2014-01-01

    Objective\\ud \\ud Interactive interventions are increasingly advocated to support behavior change for patients who have long-term conditions. Such interventions are most likely to achieve behavior change when they are based on appropriate theoretical frameworks. Developers of interventions are faced with a diverse set of behavioral theories that do not specifically address intervention development. The aim of our work was to develop a framework to guide the developers of interactive healthcare...

  2. Becoming a normal guy: Men making sense of long-term bodily changes following bariatric surgery.

    Science.gov (United States)

    Groven, Karen Synne; Galdas, Paul; Solbrække, Kari Nyheim

    2015-01-01

    To date, research on bodily changes following bariatric surgery has focused predominantly on women, leaving the long-term experience of men relatively unexplored. In this paper, we draw on interviews with men who have undergone an irreversible gastric bypass procedure to explore their bodily changes more than 4 years post-surgery. We apply a phenomenological framework that draws on Leder's perspectives on the "disappearing" and "dys-appearing" body, combined with a gender-sensitive lens that draws on Connell's theory of hegemonic masculinity and Robertson's conceptions of embodied masculinity. Our principal finding was that the men negotiated their bodily changes following bariatric surgery in profoundly ambivalent ways. Although they enthusiastically praised the surgery for improving their health, self-esteem, and social functioning, they also emphasized their efforts to cope with post-surgical side effects and life-threatening complications. Our analysis elaborates on their efforts to adjust to and come to terms with these changes, focusing on episodes of hypoglycemia, severe pain and internal herniation, and the significance of physical activity and exercise. Our findings point to the need to acknowledge men's ways of making sense of profound and ongoing bodily changes following bariatric surgery and how these negotiations are closely intertwined with masculine ideals of embodiment and social value.

  3. Becoming a normal guy: Men making sense of long-term bodily changes following bariatric surgery

    Directory of Open Access Journals (Sweden)

    Karen Synne Groven

    2015-12-01

    Full Text Available Background: To date, research on bodily changes following bariatric surgery has focused predominantly on women, leaving the long-term experience of men relatively unexplored. In this paper, we draw on interviews with men who have undergone an irreversible gastric bypass procedure to explore their bodily changes more than 4 years post-surgery. We apply a phenomenological framework that draws on Leder's perspectives on the “disappearing” and “dys-appearing” body, combined with a gender-sensitive lens that draws on Connell's theory of hegemonic masculinity and Robertson's conceptions of embodied masculinity. Findings: Our principal finding was that the men negotiated their bodily changes following bariatric surgery in profoundly ambivalent ways. Although they enthusiastically praised the surgery for improving their health, self-esteem, and social functioning, they also emphasized their efforts to cope with post-surgical side effects and life-threatening complications. Our analysis elaborates on their efforts to adjust to and come to terms with these changes, focusing on episodes of hypoglycemia, severe pain and internal herniation, and the significance of physical activity and exercise. Conclusions: Our findings point to the need to acknowledge men's ways of making sense of profound and ongoing bodily changes following bariatric surgery and how these negotiations are closely intertwined with masculine ideals of embodiment and social value.

  4. The relationship of long term global temperature change and human fertility.

    Science.gov (United States)

    Fisch, Harry; Andrews, Howard F; Fisch, Karen S; Golden, Robert; Liberson, Gary; Olsson, Carl A

    2003-07-01

    According to the United Nations, global fertility has declined in the last century as reflected by a decline in birth rates. The earth's surface air temperature has increased considerably and is referred to as global warming. Since changes in temperature are well known to influence fertility we sought to determine if a statistical relationship exists between long-term changes in global air temperatures and birth rates. The most complete and reliable birth rate data in the 20th century was available in 19 industrialized countries. Using bivariate and multiple regression analysis, we compared yearly birth rates from these countries to global air temperatures from 1900 to 1994.A common pattern of change in birth rates was noted for the 19 industrialized countries studied. In general, birth rates declined markedly throughout the century except during the baby boom period of approximately 1940 to 1964. An inverse relationship was found between changes in global temperatures and birth rates in all 19 countries. Controlling for the linear yearly decline in birth rates over time, this relationship remained statistically significant for all the 19 countries in aggregate and in seven countries individually (phuman fertility may have been influenced by change in environmental temperatures.

  5. Changes in the Long-Term Intensity Variations in Cygnus X-2 and LMC X-3

    Science.gov (United States)

    Paul, B.; Kitamoto, S.; Makino, F.

    2000-01-01

    We report the detection of changes in the long-term intensity variations in two X-ray binaries, Cyg X-2 and LMC X-3. In this work, we have used the long-term light curves obtained with the All-Sky Monitors (ASMs) of the Rossi X-Ray Timing Explorer (RXTE), Ginga, Ariel 5, and Vela 5B and the scanning modulation collimator of HEAO 1. It is found that in the light curves of both the sources, obtained with these instruments at various times over the last 30 years, more than one periodic or quasi-periodic component is always present. The multiple prominent peaks in the periodograms have frequencies unrelated to each other. In Cyg X-2, RXTE-ASM data show strong peaks at 40.4 and 68.8 days, and Ginga-ASM data show strong peaks at 53.7 and 61.3 days. Multiple peaks are also observed in LMC X-3. The various strong peaks in the periodograms of LMC X-3 appear at 104, 169, and 216 days (observed with RXTE-ASM) and 105, 214, and 328 days (observed with Ginga-ASM). The present results, when compared with the earlier observations of periodicities in these two systems, demonstrate the absence of any stable long period. The 78 day periodicity detected earlier in Cyg X-2 was probably due to the short time base in the RXTE data that were used, and the periodicity of 198 days in LMC X-3 was due to a relatively short duration of observation with HEAO 1.

  6. A prospective cohort study of long-term cognitive changes in older Medicare beneficiaries.

    Science.gov (United States)

    Wolinsky, Fredric D; Bentler, Suzanne E; Hockenberry, Jason; Jones, Michael P; Weigel, Paula A; Kaskie, Brian; Wallace, Robert B

    2011-09-20

    Promoting cognitive health and preventing its decline are longstanding public health goals, but long-term changes in cognitive function are not well-documented. Therefore, we first examined long-term changes in cognitive function among older Medicare beneficiaries in the Survey on Assets and Health Dynamics among the Oldest Old (AHEAD), and then we identified the risk factors associated with those changes in cognitive function. We conducted a secondary analysis of a prospective, population-based cohort using baseline (1993-1994) interview data linked to 1993-2007 Medicare claims to examine cognitive function at the final follow-up interview which occurred between 1995-1996 and 2006-2007. Besides traditional risk factors (i.e., aging, age, race, and education) and adjustment for baseline cognitive function, we considered the reason for censoring (entrance into managed care or death), and post-baseline continuity of care and major health shocks (hospital episodes). Residual change score multiple linear regression analysis was used to predict cognitive function at the final follow-up using data from telephone interviews among 3,021 to 4,251 (sample size varied by cognitive outcome) baseline community-dwelling self-respondents that were ≥ 70 years old, not in managed Medicare, and had at least one follow-up interview as self-respondents. Cognitive function was assessed using the 7-item Telephone Interview for Cognitive Status (TICS-7; general mental status), and the 10-item immediate and delayed (episodic memory) word recall tests. Mean changes in the number of correct responses on the TICS-7, and 10-item immediate and delayed word recall tests were -0.33, -0.75, and -0.78, with 43.6%, 54.9%, and 52.3% declining and 25.4%, 20.8%, and 22.9% unchanged. The main and most consistent risks for declining cognitive function were the baseline values of cognitive function (reflecting substantial regression to the mean), aging (a strong linear pattern of increased decline

  7. Climate Change

    DEFF Research Database (Denmark)

    Rasmussen, Torben Valdbjørn; Hansen, Ernst Jan de Place

    2011-01-01

    This paper presents the effects of climate change relevant for Denmark, including the change in mean year values as well as the extent of maximum and minimum extremes. Described by the Intergovernmental Panel on Climate Change, the assumptions that the scenarios are based on were outlined...... and evaluated in a Danish context. The uncertainty of the scenarios leaves major challenges that, if not addressed and taken into account in building design, will grow far more serious as climate change progresses. Cases implemented in the Danish building stock illustrate adaptation to climate change...... and illustrate how building design can include mitigating measures to counteract climate change. Cases studied were individual buildings as well as the urban environment. Furthermore the paper describes some of the issues that must be addressed, as the building sector is investing in measures to adapt to climate...

  8. Long-term change in the megabenthos of the Porcupine Abyssal Plain (NE Atlantic)

    Science.gov (United States)

    Billett, D. S. M.; Bett, B. J.; Rice, A. L.; Thurston, M. H.; Galéron, J.; Sibuet, M.; Wolff, G. A.

    A radical change in the abundance of invertebrate megafauna on the Porcupine Abyssal Plain is reported over a period of 10 years (1989-1999). Actiniarians, annelids, pycnogonids, tunicates, ophiuroids and holothurians increased significantly in abundance. However, there was no significant change in wet weight biomass. Two holothurian species, Amperima rosea and Ellipinion molle, increased in abundance by more than two orders of magnitude. Samples from the Porcupine Abyssal Plain over a longer period (1977-1999) show that prior to 1996 these holothurian species were always a minor component of the megafauna. From 1996 to 1999 A. rosea was abundant over a wide area of the Porcupine Abyssal Plain indicating that the phenomenon was not a localised event. Several dominant holothurian species show a distinct trend in decreasing body size over the study period. The changes in megafauna abundance may be related to environmental forcing (food supply) rather than to localised stochastic population variations. Inter-annual variability and long-term trends in organic matter supply to the seabed may be responsible for the observed changes in abundance, species dominance and size distributions.

  9. Long-term Increases in Flower Production by Growth Forms in Response to Anthropogenic Change in a Tropical Forest

    Science.gov (United States)

    Pau, S.; Wright, S. J.

    2016-12-01

    There is mounting evidence that anthropogenic global change is altering the ecology of tropical forests. A limited number of studies have focused on long-term trends in tropical reproductive activity, yet differences in reproductive activity should have consequences for demography and ultimately forest carbon, water, and energy balance. Here we analyze a 28-year record of tropical flower production in response to anthropogenic climate change. We show that a multi-decadal increase in flower production is most strongly driven by rising atmospheric CO2, which had approximately 8x the effect of the Multivariate ENSO Index and approximately 13x the effect of rainfall or solar radiation. Interannual peaks in flower production were associated with greater solar radiation and low rainfall during El Niño years. Observed changes in solar radiation explained flower production better than rainfall (models including solar radiation accounted for 94% of cumulative AICc weight compared to 87% for rainfall). All growth forms (lianas, canopy trees, midstory trees, and shrubs) produced more flowers with increasing CO2 except for understory treelets. The increase in flower production was matched by a lengthening of flowering duration for canopy trees and midstory trees; duration was also longer for understory treelets. Given that anthropogenic CO2 emissions will continue to climb over the next century, the long-term increase in flower production may persist unless offset by increasing cloudiness in the tropics, or until rising CO2 and/or warming temperatures associated with the greenhouse effect pass critical thresholds for plant reproduction.

  10. Long-term changes in community assembly, resistance, and resilience following experimental floods.

    Science.gov (United States)

    Robinson, Christopher T

    2012-10-01

    This study examined the long-term changes in community assembly, resistance, and resilience of macroinvertebrates following 10 years of experimental floods in a flow regulated river. Physico-chemistry, macroinvertebrates, and periphyton biomass were monitored before and sequentially after each of 22 floods, and drift/seston was collected during six separate floods over the study period. The floods reduced the density and taxon richness of macroinvertebrates, and a nonmetric dimensional scaling (NMDS) analysis distinguished temporal shifts in community assembly. Resistance (measured as the relative lack of loss in density) tofloods varied among taxa, and the abundance of resistant taxa was related to the temporal changes in community assembly. Community resistance was inversely related to flood magnitude with all larger floods (> 25 m3/s, > 16-fold over baseflow) reducing densities by > 75% regardless of flood year, whereas smaller floods (floods. No relationship was found between flood magnitude and the relative loss in periphyton biomass. Resilience was defined as the recovery slope (positive slope of a parameter with time following each flood) and was unrelated to shifts in community assembly or resistance. Macroinvertebrate drift and seston demonstrated hysteresis (i.e., a temporal response in parameter quantity with change in discharge) during each flood, although larger floods typically had two peaks in both parameters. The first peak was a response to the initial increases in flow, whereas the second peak was associated with streambed disturbance (substrate mobility) and side-slope failure causing increased scour. Drift density was 3-9 times greater and that of seston 3-30 times greater during larger floods than smaller floods. These results demonstrate temporal shifts in macroinvertebrate community assembly toward a pre-dam assemblage following sequential floods in this flow regulated river, thus confirming the ecological role of habitat filtering in

  11. Persistent, Long-term Cerebral White Matter Changes after Sports-Related Repetitive Head Impacts

    Science.gov (United States)

    Bazarian, Jeffrey J.; Zhu, Tong; Zhong, Jianhui; Janigro, Damir; Rozen, Eric; Roberts, Andrew; Javien, Hannah; Merchant-Borna, Kian; Abar, Beau; Blackman, Eric G.

    2014-01-01

    Introduction Repetitive head impacts (RHI) sustained in contact sports are thought to be necessary for the long-term development of chronic traumatic encephalopathy (CTE). Our objectives were to: 1) characterize the magnitude and persistence of RHI-induced white matter (WM) changes; 2) determine their relationship to kinematic measures of RHI; and 3) explore their clinical relevance. Methods Prospective, observational study of 10 Division III college football players and 5 non-athlete controls during the 2011-12 season. All subjects underwent diffusion tensor imaging (DTI), physiologic, cognitive, and balance testing at pre-season (Time 1), post-season (Time 2), and after 6-months of no-contact rest (Time 3). Head impact measures were recorded using helmet-mounted accelerometers. The percentage of whole-brain WM voxels with significant changes in fractional anisotropy (FA) and mean diffusivity (MD) from Time 1 to 2, and Time 1 to 3 was determined for each subject and correlated to head impacts and clinical measures. Results Total head impacts for the season ranged from 431–1,850. No athlete suffered a clinically evident concussion. Compared to controls, athletes experienced greater changes in FA and MD from Time 1 to 2 as well as Time 1 to 3; most differences at Time 2 persisted to Time 3. Among athletes, the percentage of voxels with decreased FA from Time 1 to 2 was positively correlated with several helmet impact measures. The persistence of WM changes from Time 1 to 3 was also associated with changes in serum ApoA1 and S100B autoantibodies. WM changes were not consistently associated with cognition or balance. Conclusions A single football season of RHIs without clinically-evident concussion resulted in WM changes that correlated with multiple helmet impact measures and persisted following 6 months of no-contact rest. This lack of WM recovery could potentially contribute to cumulative WM changes with subsequent RHI exposures. PMID:24740265

  12. Conversion from long-term cultivated wheat field to Jerusalem artichoke plantation changed soil fungal communities

    Science.gov (United States)

    Zhou, Xingang; Zhang, Jianhui; Gao, Danmei; Gao, Huan; Guo, Meiyu; Li, Li; Zhao, Mengliang; Wu, Fengzhi

    2017-01-01

    Understanding soil microbial communities in agroecosystems has the potential to contribute to the improvement of agricultural productivity and sustainability. Effects of conversion from long-term wheat plantation to Jerusalem artichoke (JA) plantation on soil fungal communities were determined by amplicon sequencing of total fungal ITS regions. Quantitative PCR and PCR-denaturing gradient gel electrophoresis were also used to analyze total fungal and Trichoderma spp. ITS regions and Fusarium spp. Ef1α genes. Results showed that soil organic carbon was higher in the first cropping of JA and Olsen P was lower in the third cropping of JA. Plantation conversion changed soil total fungal and Fusarium but not Trichoderma spp. community structures and compositions. The third cropping of JA had the lowest total fungal community diversity and Fusarium spp. community abundance, but had the highest total fungal and Trichoderma spp. community abundances. The relative abundances of potential fungal pathogens of wheat were higher in the wheat field. Fungal taxa with plant growth promoting, plant pathogen or insect antagonistic potentials were enriched in the first and second cropping of JA. Overall, short-term conversion from wheat to JA plantation changed soil fungal communities, which is related to changes in soil organic carbon and Olsen P contents.

  13. Modeling studies of unsaturated flow with long-term permeability change at Yucca Mountain

    International Nuclear Information System (INIS)

    Zhang Chengyuan; Liu Xiaoyan; Liu Quansheng

    2008-01-01

    The amount of water seeping into the waste emplacement drifts is crucial for the performance of underground nuclear waste repository, since it controls the corrosion rates of waste packages and the mobilization rate of radionuclides. It is limited by water flow through drift vicinity. In the present work we study the potential rates of water flow around drifts as a function of predicted long-term change of permeability at Yucca Mountain, based on a dual-continuum model of the unsaturated flow in fractured rock mass. For stage of DECOVALEX Ⅳ, we used a simplified practical model on unsaturated flow in Yucca Mountain case simulation. These models contain main physical processes that should be considered, including thermal expansion, thermal radiation, water-rock coupling and stress-induced change of permeability. Comparative study with other DECOVALEX team's results shows that they are both good enough and flexible enough to include more physical processes. We can draw the conclusion that it is necessary to model stress-induced changes in permeability and relative processes in future studies, because there are obvious differences (in water saturation and water flux) between simulation cases with and without variable permeability, especially in areas very close to the drift. (authors)

  14. Long-term changes in retinal vascular diameter and cognitive impairment in type 1 diabetes.

    Science.gov (United States)

    Nunley, Karen A; Metti, Andrea L; Klein, Ronald; Klein, Barbara E; Saxton, Judith A; Orchard, Trevor J; Costacou, Tina; Aizenstein, Howard J; Rosano, Caterina

    2018-05-01

    To assess associations between cognitive impairment and longitudinal changes in retinal microvasculature, over 18 years, in adults with type 1 diabetes. Participants of the Pittsburgh Epidemiology of Diabetes Complications Study received ≥3 fundus photographs between baseline (1986-1988) and time of cognitive assessment (2010-2015: N = 119; 52% male; mean age and type 1 diabetes duration 43 and 34 years, respectively). Central retinal arteriolar equivalent and central retinal venular equivalent were estimated via computer-based methods; overall magnitude and speed of narrowing were quantified as cumulative average and slope, respectively. Median regression models estimated associations of central retinal arteriolar equivalent and central retinal venular equivalent measures with cognitive impairment status, adjusted for type 1 diabetes duration. Interactions with HbA1c, proliferative retinopathy and white matter hyperintensities were assessed. Compared with participants without cognitive impairment, those with clinically relevant cognitive impairment experienced 1.8% greater and 31.1% faster central retinal arteriolar equivalent narrowing during prior years (t = -2.93, p = 0.004 and t = -3.97, p impairment. Long-term arterial retinal changes could indicate type 1 diabetes-related cognitive impairment. Studies examining longitudinal central retinal arteriolar equivalent changes as early biomarkers of cognitive impairment risk are warranted.

  15. Long-term effect of a name change for schizophrenia on reducing stigma.

    Science.gov (United States)

    Koike, Shinsuke; Yamaguchi, Sosei; Ojio, Yasutaka; Shimada, Takafumi; Watanabe, Kei-ichiro; Ando, Shuntaro

    2015-10-01

    A name change for schizophrenia was first implemented in Japan for reducing stigma in 2002; however, little is known of its long-term impact. Total 259 students from 20 universities answered an anonymous self-administered questionnaire about their mental health-related experiences, and stigma scales including feasible knowledge and negative stereotypes for four specific diseases, including schizophrenia (old and new names), depression, and diabetes mellitus. We also asked to choose the old and new names of schizophrenia and dementia among ten names for mental and physical illnesses and conditions. The participants had more feasible knowledge and fewer negative stereotypes for the new name of schizophrenia than the old name, but were still significantly worse than for depression and diabetes mellitus (p stereotypes (β = 0.13, p = 0.020). The rate of correct responses for the old and new names of schizophrenia was significantly lower than that of dementia (41 vs. 87%, p media was associated with the recognition of name change for schizophrenia (p = 0.008), which was associated with less feasible knowledge for new name of schizophrenia. The name change of schizophrenia has reduced stigma since 12 years have passed. More effective campaigns, educational curricula, and policy making are needed to reduce stigma toward schizophrenia.

  16. Effects of harvesting forest biomass on water and climate regulation services: A synthesis of long-term ecosystem experiments in eastern North America

    Science.gov (United States)

    Caputo, Jesse; Beier, Colin D; Groffman, Peter M; Burns, Douglas A.; Beall, Frederick D; Hazlett, Paul W.; Yorks, Thad E

    2016-01-01

    Demand for woody biomass fuels is increasing amidst concerns about global energy security and climate change, but there may be negative implications of increased harvesting for forest ecosystem functions and their benefits to society (ecosystem services). Using new methods for assessing ecosystem services based on long-term experimental research, post-harvest changes in ten potential benefits were assessed for ten first-order northern hardwood forest watersheds at three long-term experimental research sites in northeastern North America. As expected, we observed near-term tradeoffs between biomass provision and greenhouse gas regulation, as well as tradeoffs between intensive harvest and the capacity of the forest to remediate nutrient pollution. In both cases, service provision began to recover along with the regeneration of forest vegetation; in the case of pollution remediation, the service recovered to pre-harvest levels within 10 years. By contrast to these two services, biomass harvesting had relatively nominal and transient impacts on other ecosystem services. Our results are sensitive to empirical definitions of societal demand, including methods for scaling societal demand to ecosystem units, which are often poorly resolved. Reducing uncertainty around these parameters can improve confidence in our results and increase their relevance for decision-making. Our synthesis of long-term experimental studies provides insights on the social-ecological resilience of managed forest ecosystems to multiple drivers of change.

  17. Methods for definition of reference conditions for a repository site taking long-term environmental change into account

    Energy Technology Data Exchange (ETDEWEB)

    Ikonen, A.T.K. [Environmental Research and Assessment EnviroCase, Ltd. (Finland)

    2014-07-01

    In a few countries, programmes for disposal of spent nuclear fuel have proceeded into a site-specific phase, and the number of low- and intermediate-level nuclear waste repositories requiring updated state-of-the-art long-term safety assessments is considerable. In this contribution, the approach employed in the Finnish spent fuel disposal programme is analysed and used as an example for a more general methodology for defining reference surface conditions for a site, e.g. to guide selection of representative input data to safety assessments, using spatio-temporal analogues so that long-term environmental changes are taken into account. The contribution incorporates also elements from discussions in the IAEA EMRAS II and MODARIA working groups on addressing the environmental change in the assessments. The legacy of the earlier BIOMASS project is also recognised. Broadly, the methods to be presented include identification of similarity factors (e.g. geological, biological and climate regimes) upon which a reference area can be delineated. Within the reference area, characteristic lines of development and biotopes are identified and described, and these are then used to guide further research and application of literature data to iteratively accumulate adequate understanding of the site conditions and relevant processes at the present and in the future (by projecting further the past and present development lines and biotopes). In this iterative approach, also the intensity of research efforts can be adjusted with the stage of the repository programme, as will be discussed in the complete contribution. Document available in abstract form only. (authors)

  18. Long term impact of organic amendments on forest soil properties under semiarid Mediterranean climatic conditions

    Science.gov (United States)

    Hueso González, Paloma; Francisco Martinez Murillo, Juan; Damian Ruiz Sinoga, Jose

    2017-04-01

    postafforestation); (iv) spring 2015 (42 months postafforestation) and; (v) spring 2016 (54 months postafforestation). The sampling strategy for each plot involved the collection of four disturbed soil samples taken from the surface (0 to 10-cm depth). The soil properties analyzed were as follows: (i) soil organic carbon (SOC); (ii) pH; (iii) electrical conductivity (EC); (iv) aggregates stability (AS) and; (v) texture (TE). Regarding to soil aggregate stability, 54 month after the afforestation, the percentage of stable aggregates has increased slightly in all the treatments (HP, RU, PM, SM and SH) in relation to control. Specifically, the differences were recorded in the fraction of macroaggregates (≥ 0.250 mm). The largest increases have been associated with SM, PM and RU treatments. Although the SM, PM and RU treatments helped to maintain the SOC at high levels in the 54 months following application. Conversely, not significant differences relative to the control plots were found for the pH, EC or texture, 54 months following afforestation. To conclude, these results showed an increase in the SOC and the stability of the macroaggregates when soil is amended with sludge, pinus mulch and straw much. This fact has been due to an increase in the number cementing agents due to: (i) the application of pinus, straw and sludge had resulted in the release of carbohydrates to the soil; and thus (ii) it has favored the development of a protective vegetation cover, which has increased the number of roots in the soil and the organic contribution to it. References: Casals P, Cortina J, Bottner P, Coûteaux MM, Vallejo VR.: CO2 efflux from a Mediterranean semi-arid forest soil. I. Seasonality and effects of stoniness. Biogeochemistry 48: 261-281, 2000. Eaton JM, McGoff NM, Byrne KA, Leahy P, Kiely G.: Land cover change and soil organic C stocks in the Republic of Ireland 1851-2000. Climatic Change 91: 317-334, 2008. García-Orenes F, Guerrero C, Roldán A, Mataix-Solera J, Cerdà A, Campoy

  19. Extreme precipitation and long-term precipitation changes in a Central European sedge-grass marsh in the context of flood occurrence

    Czech Academy of Sciences Publication Activity Database

    Dušek, Jiří; Hudecová, S.; Stellner, Stanislav

    2017-01-01

    Roč. 62, č. 11 (2017), s. 1796-1808 ISSN 0262-6667 R&D Projects: GA MŠk(CZ) LO1415; GA MŠk(CZ) LM2015061; GA ČR(CZ) GBP402/12/G097 Institutional support: RVO:86652079 Keywords : wetland * extremes * long-term monitoring * probability * rain spells * global climate change * rainfall Subject RIV: DA - Hydrology ; Limnology OBOR OECD: Hydrology Impact factor: 2.222, year: 2016

  20. Colour changes in prints during long-term dark storage of prints

    International Nuclear Information System (INIS)

    Parraman, Carinna

    2010-01-01

    The most significant impact on colour fading in prints is exposure to light and air. However what happens to coloured prints during long-term storage in boxes, drawers and on shelves? Measurements of samples, printed in July 2005, stored in a range of light and darkened storage conditions have shown some interesting initial results. As more emphasis is placed on the effects of light, the dark stability of inkjet prints is relatively overlooked when considering how to preserve or store coloured prints. This study and presentation builds on previous research [1] and has concentrated on the changes to colour during storage. With reference to ASTM F2035 - 00(2006) Standard Practice for Measuring the Dark Stability of Ink Jet Prints, the Standards outline points out that whilst natural aging is the most reliable method of assessing image stability, materials and inks any data that is produced quickly becomes redundant; therefore accelerated aging is more preferred. However, the fine art materials in this study are still very much in circulation. The leading fine art papers, and pigmented ink-sets used in these trials are still being used by artists. We can therefore demonstrate the characteristics of colour changes and the impact of ink on paper that utilises natural aging methods.

  1. Deviations in energy sensing predict long-term weight change in overweight Native Americans.

    Science.gov (United States)

    Basolo, Alessio; Votruba, Susanne B; Heinitz, Sascha; Krakoff, Jonathan; Piaggi, Paolo

    2018-05-01

    Energy expenditure (EE), as reflective of body energy demand, has been proposed to be the key driver of food intake, possibly influencing weight change in humans. Variation in this energy-sensing link (overeating relative to weight-maintaining energy requirements) may lead to weight gain over time. Sixty-one overweight otherwise healthy Native Americans (age: 34.0 ± 7.9 years, body fat: 39.7 ± 9.5%, 36 males) were admitted to our clinical research unit for measurements of body composition by dual-energy X-ray absorptiometry, and 24-h EE and respiratory quotient (RQ) in a whole-room indirect calorimeter during energy balance and weight stability. Following this, ad libitum food intake was assessed for three days using computerized vending machines. Body weight change under unrestricted free-living conditions was assessed at an outpatient follow-up visit (median follow-up time = 1.7 years). Total ad libitum food intake (3-day average) was positively associated with 24-h EE (r = 0.44, p energy requirements can be assessed and predicts long-term weight gain, suggesting that variation in energy sensing may influence appetite by favoring overeating thus promoting obesity development. Copyright © 2018. Published by Elsevier Inc.

  2. Long-term weight changes in obese young adult men and subsequent all-cause mortality

    DEFF Research Database (Denmark)

    Zimmermann, E; Berentzen, T L; Ängquist, Lars Henrik

    2013-01-01

    change and all-cause mortality in a broad range of body mass index (BMI) in young men.METHODS:Among 362200 Danish draftees, examined between 1943 and 1977, all obese (BMI 31.0 kg m(-2); n=1930), and a random 1% sample of the others (n=3601) were identified at a mean age of 20 years (range: 18-25 years......BACKGROUND:Although the expectation is that weight gain increases mortality and weight loss among those overweight reduces mortality, results on weight gain and mortality in young adults are conflicting, and weight loss is less explored. We investigated the association between long-term weight......). All the obese and half the controls were re-examined between 4 and 40 years later (mean age 35 years). Weight changes were defined as: weight loss 0.1 kg m(-2) per year. Hazard ratios (HR) and 95% confidence intervals (CI) were estimated using Cox regression.RESULTS:Among the 908 obese and 1073...

  3. Predicting the impact of long-term temperature changes on the epidemiology and control of schistosomiasis: a mechanistic model.

    Directory of Open Access Journals (Sweden)

    Tara D Mangal

    2008-01-01

    Full Text Available Many parasites of medical and veterinary importance are transmitted by cold-blooded intermediate hosts or vectors, the abundance of which will vary with ambient temperatures, potentially altering disease prevalence. In particular, if global climate change will increase mean ambient temperature in a region endemic with a human pathogen then it is possible that the incidence of disease will similarly increase. Here we examine this possibility by using a mathematical model to explore the effects of increasing long-term mean ambient temperature on the prevalence and abundance of the parasite Schistosoma mansoni, the causative agent of schistosomiasis in humans.The model showed that the impact of temperature on disease prevalence and abundance is not straightforward; the mean infection burden in humans increases up to 30 degrees C, but then crashes at 35 degrees C, primarily due to increased mortalities of the snail intermediate host. In addition, increased temperatures changed the dynamics of disease from stable, endemic infection to unstable, epidemic cycles at 35 degrees C. However, the prevalence of infection was largely unchanged by increasing temperatures. Temperature increases also affected the response of the model to changes in each parameter, indicating certain control strategies may become less effective with local temperature changes. At lower temperatures, the most effective single control strategy is to target the adult parasites through chemotherapy. However, as temperatures increase, targeting the snail intermediate hosts, for example through molluscicide use, becomes more effective.These results show that S. mansoni will not respond to increased temperatures in a linear fashion, and the optimal control strategy is likely to change as temperatures change. It is only through a mechanistic approach, incorporating the combined effects of temperature on all stages of the life-cycle, that we can begin to predict the consequences of climate

  4. Long-term climate monitoring by the global climate observing system: report of breakout group 1 - climate forcings and feedbacks

    International Nuclear Information System (INIS)

    Miller, C.; Bretherton, F.

    1995-01-01

    The assignment for Breakout Group A was to re-visit and expand upon the plenary session discussion on climate forcings and feedbacks and to develop a set of recommendations for each of the science disciplines or activities covered within this breakout category. Working guidelines for the group included identifying: (1) what has to be done; (2) why it has to be done, i.e. who is the customer? (3) the process for remedying deficiencies and, specifically, how to leverage the activities at operational centers; and (4) priorities (recognizing that it is premature to distinguish between major systems). The science ares addressed included: greenhouse gases (GHGs); radiation budget; water vapor; aerosols; clouds; precipitation; tropospheric ozone; and solar radiation. The role of climate satellites was also noted

  5. Analysis of long-term geological and hydrogeological changes in the Swedish programme for final disposal of nuclear waste

    International Nuclear Information System (INIS)

    Ericsson, L.O.; Boulton, G.S.

    1996-01-01

    In assessing the safety of deep disposal of nuclear waste in crystalline rocks it is important establish whether recent or future changes in loading can lead to fracturing and block displacement which may change the hydrogeological setting of a repository. Furthermore, it is of vital importance to understand how future climate changes, especially future glaciations, will influence the groundwater flow around a deep repository. The Swedish programme comprises R and D activities which attempt to quantify probable impacts of earthquakes, glaciation and land uplift. The activities emphasize geodynamic processes in the Baltic Shield, post-glacial faulting and glacial impacts on hydrogeology and ground water chemistry. A time-dependent, thermo-mechanically coupled, three-dimensional model of the ice sheet behaviour in Scandinavia has been developed. The model is driven by changes in the elevation of the permanent snow line on its surface and by air temperature and predicts the behaviour of the ice sheet for an earth's surface of given form and mechanical properties. The ice sheet model reconstructs the ice sheet thickness, ice sheet temperature distribution, including basal temperature, basal meting pattern and velocity distribution. The model is coupled to a sub-glacial Dancian groundwater flow model which in turn provides boundary for evaluations of long-term hydrogeological evolution at specific sites. (authors). 22 refs., 3 figs

  6. [Chronic pain patients' readiness to change after multimodal treatment. Short- and long-term effects].

    Science.gov (United States)

    Küchler, A; Sabatowski, R; Kaiser, U

    2012-12-01

    , significant short- and long-term improvements were evident. For single outcome parameters, positive associations with the stages of readiness to change were found. The results indicate that the outpatient pain management program favorably affects patients' motivation and general quality of life. This effect also seems to be stable over a long period of time. As not all patients show an improvement in stage of readiness to change, the question arises whether the reason of the differences might lie within the patients' and whether specific interventions for motivation might be useful to enhance motivation before starting treatment.

  7. Rural Districts between Urbanization and Land Abandonment: Undermining Long-Term Changes in Mediterranean Landscapes

    Directory of Open Access Journals (Sweden)

    Ilaria Zambon

    2018-04-01

    Full Text Available The present study investigates changes in the rural landscapes of a Mediterranean country (Greece over a long time period (1970–2015 encompassing economic expansions and recessions. Using a spatial distribution of 5 basic agricultural land-use classes (arable land, garden crop, vineyards, tree crop and fallow land derived from official statistics at 6 years (1970, 1979, 1988, 1997, 2006, 2015, a quantitative analysis based on correlation and multivariate techniques was carried out to identify recent changes in the Greek agricultural landscape at prefectural level during different economic waves. Empirical results evidenced both intuitive and counter-intuitive landscape transformations, including: (i a progressive, spatially-homogeneous reduction of cropland; (ii a (more or less rapid decrease in the surface of high-input crops, including arable land, horticulture and vineyards; (iii a parallel increase in the surface of tree crops, especially olive; (iv a spatially-heterogeneous decrease of fallow land concentrated in metropolitan and tourism districts, especially in the last decade; and, finally, (v increasingly diversified landscapes in rural, accessible areas close to the sea coast. Based on a correlation analysis with background socioeconomic indicators, our findings reflect the multiple impacts of urbanization and land abandonment on the composition and diversity of rural landscapes. Changes in agricultural land-use were moulded by multiple drivers depending on latent transformations in rural systems and inherent conflicts with expanding urban regions. Together with market conditions and the Common Agricultural Policy subsidy regime, social contexts and the economic cycle are important when identifying long-term changes in agricultural landscapes, especially in transitional socio-ecological systems.

  8. Long-term changes in the extractability and bioavailability of zinc and cadmium after sludge application

    Energy Technology Data Exchange (ETDEWEB)

    McGrath, S.P.; Zhao, F.J.; Dunham, S.J.; Crosland, A.R.; Coleman, K.

    2000-06-01

    Changes in the extractability and uptake by crops of sludge metals in a long-term field experiment, started in 1942, were measured to assess whether Zn and Cd are either fixed by the sludge/soil constituents or are released as the sludge organic matter (OM) decomposes. Total and 0.1 M CaCl{sub 2}-extractable concentrations of Zn and Cd in soil and total concentrations in crops were measured on archived crop and soil samples. Extractability of Zn as a proportion of the total ranged from 0.5 to 3% and that of Cd from 4 to 18%, and were higher in sludge-amended than farmyard manure or fertilizer-amended soils. Over a 23-yr period after 1961, when sludge was last applied, the extractability of both metals fluctuated, but neither decreased nor increased consistently. The relationships between total soil and crop metal concentrations were linear, with no evidence of a plateau across the range of soil metal concentrations achieved. The slopes of the soil-plant relationships depended on the type of crop or crop part examined, but were generally in the order red beet (Beta vulgaris L.) > sugar beet (Beta vulgaris L.) > carrot (Daucus carota L.) > barley (Hordeum vulgare L.). However, there also were large seasonal differences in metal concentrations in the crops. It is concluded from the available evidence that up to 23 yr after sludge applications cease, Zn and Cd extractability and bioavailability do not decrease.

  9. The long-term fate of permafrost peatlands under rapid climate warming

    Science.gov (United States)

    Swindles, Graeme T.; Morris, Paul J.; Mullan, Donal; Watson, Elizabeth J.; Turner, T. Edward; Roland, Thomas P.; Amesbury, Matthew J.; Kokfelt, Ulla; Schoning, Kristian; Pratte, Steve; Gallego-Sala, Angela; Charman, Dan J.; Sanderson, Nicole; Garneau, Michelle; Carrivick, Jonathan L.; Woulds, Clare; Holden, Joseph; Parry, Lauren; Galloway, Jennifer M.

    2015-01-01

    Permafrost peatlands contain globally important amounts of soil organic carbon, owing to cold conditions which suppress anaerobic decomposition. However, climate warming and permafrost thaw threaten the stability of this carbon store. The ultimate fate of permafrost peatlands and their carbon stores is unclear because of complex feedbacks between peat accumulation, hydrology and vegetation. Field monitoring campaigns only span the last few decades and therefore provide an incomplete picture of permafrost peatland response to recent rapid warming. Here we use a high-resolution palaeoecological approach to understand the longer-term response of peatlands in contrasting states of permafrost degradation to recent rapid warming. At all sites we identify a drying trend until the late-twentieth century; however, two sites subsequently experienced a rapid shift to wetter conditions as permafrost thawed in response to climatic warming, culminating in collapse of the peat domes. Commonalities between study sites lead us to propose a five-phase model for permafrost peatland response to climatic warming. This model suggests a shared ecohydrological trajectory towards a common end point: inundated Arctic fen. Although carbon accumulation is rapid in such sites, saturated soil conditions are likely to cause elevated methane emissions that have implications for climate-feedback mechanisms. PMID:26647837

  10. Energy systems and climate policy - Long-term scenarios for an uncertain future

    NARCIS (Netherlands)

    Vuuren, D.P. van

    2007-01-01

    In this thesis various forms of scenario analysis are discussed both to explore 1) how energy system and associated greenhouse gas emissions may develop in the absence of climate policy and 2) how strategies aimed at drastically reducing greenhouse gas emissions may turn out. As uncertainties

  11. Long-term changes in species composition and relative abundances of sharks at a provisioning site.

    Science.gov (United States)

    Brunnschweiler, Juerg M; Abrantes, Kátya G; Barnett, Adam

    2014-01-01

    Diving with sharks, often in combination with food baiting/provisioning, has become an important product of today's recreational dive industry. Whereas the effects baiting/provisioning has on the behaviour and abundance of individual shark species are starting to become known, there is an almost complete lack of equivalent data from multi-species shark diving sites. In this study, changes in species composition and relative abundances were determined at the Shark Reef Marine Reserve, a multi-species shark feeding site in Fiji. Using direct observation sampling methods, eight species of sharks (bull shark Carcharhinus leucas, grey reef shark Carcharhinus amblyrhynchos, whitetip reef shark Triaenodon obesus, blacktip reef shark Carcharhinus melanopterus, tawny nurse shark Nebrius ferrugineus, silvertip shark Carcharhinus albimarginatus, sicklefin lemon shark Negaprion acutidens, and tiger shark Galeocerdo cuvier) displayed inter-annual site fidelity between 2003 and 2012. Encounter rates and/or relative abundances of some species changed over time, overall resulting in more individuals (mostly C. leucas) of fewer species being encountered on average on shark feeding dives at the end of the study period. Differences in shark community composition between the years 2004-2006 and 2007-2012 were evident, mostly because N. ferrugineus, C. albimarginatus and N. acutidens were much more abundant in 2004-2006 and very rare in the period of 2007-2012. Two explanations are offered for the observed changes in relative abundances over time, namely inter-specific interactions and operator-specific feeding protocols. Both, possibly in combination, are suggested to be important determinants of species composition and encounter rates, and relative abundances at this shark provisioning site in Fiji. This study, which includes the most species from a spatially confined shark provisioning site to date, suggests that long-term provisioning may result in competitive exclusion among shark

  12. Long-term changes in species composition and relative abundances of sharks at a provisioning site.

    Directory of Open Access Journals (Sweden)

    Juerg M Brunnschweiler

    Full Text Available Diving with sharks, often in combination with food baiting/provisioning, has become an important product of today's recreational dive industry. Whereas the effects baiting/provisioning has on the behaviour and abundance of individual shark species are starting to become known, there is an almost complete lack of equivalent data from multi-species shark diving sites. In this study, changes in species composition and relative abundances were determined at the Shark Reef Marine Reserve, a multi-species shark feeding site in Fiji. Using direct observation sampling methods, eight species of sharks (bull shark Carcharhinus leucas, grey reef shark Carcharhinus amblyrhynchos, whitetip reef shark Triaenodon obesus, blacktip reef shark Carcharhinus melanopterus, tawny nurse shark Nebrius ferrugineus, silvertip shark Carcharhinus albimarginatus, sicklefin lemon shark Negaprion acutidens, and tiger shark Galeocerdo cuvier displayed inter-annual site fidelity between 2003 and 2012. Encounter rates and/or relative abundances of some species changed over time, overall resulting in more individuals (mostly C. leucas of fewer species being encountered on average on shark feeding dives at the end of the study period. Differences in shark community composition between the years 2004-2006 and 2007-2012 were evident, mostly because N. ferrugineus, C. albimarginatus and N. acutidens were much more abundant in 2004-2006 and very rare in the period of 2007-2012. Two explanations are offered for the observed changes in relative abundances over time, namely inter-specific interactions and operator-specific feeding protocols. Both, possibly in combination, are suggested to be important determinants of species composition and encounter rates, and relative abundances at this shark provisioning site in Fiji. This study, which includes the most species from a spatially confined shark provisioning site to date, suggests that long-term provisioning may result in competitive

  13. Long term natural history data in ambulant boys with Duchenne muscular dystrophy: 36-month changes.

    Directory of Open Access Journals (Sweden)

    Marika Pane

    Full Text Available The 6 minute walk test has been recently chosen as the primary outcome measure in international multicenter clinical trials in Duchenne muscular dystrophy ambulant patients. The aim of the study was to assess the spectrum of changes at 3 years in the individual measures, their correlation with steroid treatment, age and 6 minute walk test values at baseline. Ninety-six patients from 11 centers were assessed at baseline and 12, 24 and 36 months after baseline using the 6 minute walk test and the North Star Ambulatory Assessment. Three boys (3% lost the ability to perform the 6 minute walk test within 12 months, another 13 between 12 and 24 months (14% and 11 between 24 and 36 months (12%. The 6 minute walk test showed an average overall decline of -15.8 (SD 77.3 m at 12 months, of -58.9 (SD 125.7 m at 24 months and -104.22 (SD 146.2 m at 36 months. The changes were significantly different in the two baseline age groups and according to the baseline 6 minute walk test values (below and above 350 m (p<0.001. The changes were also significantly different according to steroid treatment (p = 0.01. Similar findings were found for the North Star Ambulatory Assessment. These are the first 36 month longitudinal data using the 6 minute walk test and North Star Ambulatory Assessment in Duchenne muscular dystrophy. Our findings will help not only to have a better idea of the progression of the disorder but also provide reference data that can be used to compare with the results of the long term extension studies that are becoming available.

  14. Long term natural history data in ambulant boys with Duchenne muscular dystrophy: 36-month changes.

    Science.gov (United States)

    Pane, Marika; Mazzone, Elena Stacy; Sivo, Serena; Sormani, Maria Pia; Messina, Sonia; D'Amico, Adele; Carlesi, Adelina; Vita, Gianluca; Fanelli, Lavinia; Berardinelli, Angela; Torrente, Yvan; Lanzillotta, Valentina; Viggiano, Emanuela; D Ambrosio, Paola; Cavallaro, Filippo; Frosini, Silvia; Barp, Andrea; Bonfiglio, Serena; Scalise, Roberta; De Sanctis, Roberto; Rolle, Enrica; Graziano, Alessandra; Magri, Francesca; Palermo, Concetta; Rossi, Francesca; Donati, Maria Alice; Sacchini, Michele; Arnoldi, Maria Teresa; Baranello, Giovanni; Mongini, Tiziana; Pini, Antonella; Battini, Roberta; Pegoraro, Elena; Previtali, Stefano; Bruno, Claudio; Politano, Luisa; Comi, Giacomo P; Bertini, Enrico; Mercuri, Eugenio

    2014-01-01

    The 6 minute walk test has been recently chosen as the primary outcome measure in international multicenter clinical trials in Duchenne muscular dystrophy ambulant patients. The aim of the study was to assess the spectrum of changes at 3 years in the individual measures, their correlation with steroid treatment, age and 6 minute walk test values at baseline. Ninety-six patients from 11 centers were assessed at baseline and 12, 24 and 36 months after baseline using the 6 minute walk test and the North Star Ambulatory Assessment. Three boys (3%) lost the ability to perform the 6 minute walk test within 12 months, another 13 between 12 and 24 months (14%) and 11 between 24 and 36 months (12%). The 6 minute walk test showed an average overall decline of -15.8 (SD 77.3) m at 12 months, of -58.9 (SD 125.7) m at 24 months and -104.22 (SD 146.2) m at 36 months. The changes were significantly different in the two baseline age groups and according to the baseline 6 minute walk test values (below and above 350 m) (p<0.001). The changes were also significantly different according to steroid treatment (p = 0.01). Similar findings were found for the North Star Ambulatory Assessment. These are the first 36 month longitudinal data using the 6 minute walk test and North Star Ambulatory Assessment in Duchenne muscular dystrophy. Our findings will help not only to have a better idea of the progression of the disorder but also provide reference data that can be used to compare with the results of the long term extension studies that are becoming available.

  15. Modeling drivers of phosphorus loads in Chesapeake Bay tributaries and inferences about long-term change

    Science.gov (United States)

    Ryberg, Karen R.; Blomquist, Joel; Sprague, Lori A.; Sekellick, Andrew J.; Keisman, Jennifer

    2018-01-01

    Causal attribution of changes in water quality often consists of correlation, qualitative reasoning, listing references to the work of others, or speculation. To better support statements of attribution for water-quality trends, structural equation modeling was used to model the causal factors of total phosphorus loads in the Chesapeake Bay watershed. By transforming, scaling, and standardizing variables, grouping similar sites, grouping some causal factors into latent variable models, and using methods that correct for assumption violations, we developed a structural equation model to show how causal factors interact to produce total phosphorus loads. Climate (in the form of annual total precipitation and the Palmer Hydrologic Drought Index) and anthropogenic inputs are the major drivers of total phosphorus load in the Chesapeake Bay watershed. Increasing runoff due to natural climate variability is offsetting purposeful management actions that are otherwise decreasing phosphorus loading; consequently, management actions may need to be reexamined to achieve target reductions in the face of climate variability.

  16. Long-Term (1969-2013 Changes of Water Parameters in Neka and Tajan Rivers, Mazandaran, Iran

    Directory of Open Access Journals (Sweden)

    Jaber Aazami

    2017-03-01

    Full Text Available Background: Iran is located in the global arid zone. With an average rainfall of less than 250 mm. 25 percent is Iran of located in hyper-dry area and 40 percent in the arid area. In 2007, the World Bank report declared the annual reduction of freshwater resources in Iran 6 times more than global standards and indicators. Since at present, in Iran most available fresh water enters the water ecosystems, their management is vitally important due to climate changes and water quality parameters. Methods: In this study, long- term changes of some parameters including hardness, dissolved solids and EC, pH, HCO3, Ca, Na, Mg, Cl and SO4 were investigated for a period of 44 years in two key rivers (Neka and Tajan rivers in the north of Iran. Results: The results show that there was the same changes pattern in all parameters in both rivers. The highest level of correlation was between electrical conductivity and dissolved solids in both rivers. Also, due to the similarity of the hydrological characteristics of the rivers, the impact of area development by local people is playing a major role in the environmental health. Conclusion: Although Iran's northern regions have high rate of precipitation, status of water quality parameters is an indicator of low levels of water quality and its pollution.

  17. A Long-Term and Reproducible Passive Microwave Sea Ice Concentration Data Record for Climate Studies and Monitoring

    Science.gov (United States)

    Peng, G.; Meier, W. N.; Scott, D. J.; Savoie, M. H.

    2013-01-01

    A long-term, consistent, and reproducible satellite-based passive microwave sea ice concentration climate data record (CDR) is available for climate studies, monitoring, and model validation with an initial operation capability (IOC). The daily and monthly sea ice concentration data are on the National Snow and Ice Data Center (NSIDC) polar stereographic grid with nominal 25 km × 25 km grid cells in both the Southern and Northern Hemisphere polar regions from 9 July 1987 to 31 December 2007. The data files are available in the NetCDF data format at http://nsidc.org/data/g02202.html and archived by the National Climatic Data Center (NCDC) of the National Oceanic and Atmospheric Administration (NOAA) under the satellite climate data record program (http://www.ncdc.noaa.gov/cdr/operationalcdrs.html). The description and basic characteristics of the NOAA/NSIDC passive microwave sea ice concentration CDR are presented here. The CDR provides similar spatial and temporal variability as the heritage products to the user communities with the additional documentation, traceability, and reproducibility that meet current standards and guidelines for climate data records. The data set, along with detailed data processing steps and error source information, can be found at http://dx.doi.org/10.7265/N5B56GN3.

  18. Long-Term Forecast 2012 - An impact analysis of existing policy instruments in energy- and climate area; Laangsiktsprognos 2012 - En konsekvensanalys av gaellande styrmedel inom energi- och klimatomraadet

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2013-08-01

    The Energy Agency has a mandate that under 'Ordinance on climate reporting' (SFS 2005:626) out projections for the energy sector of the European Parliament and Council Decision No 280/2004/EC concerning a 'Mechanism for monitoring the emissions of the Community greenhouse gas'. This report contains a reference trajectory until 2030, and two sensitivity scenarios. The forecast is based on existing instruments, which means that results of the report should not be regarded as a proper projection of future energy, but as the impact of current policy instruments given different conditions such as economic growth and fuel prices. The Energy Authority's long-term forecasts are studied energy system's long-term development on the basis of policy instruments and several assumed conditions. The conditions for this long-term prognosis was established in January 2012 and has its basis in the policy instruments decided until the turn of 2011/2012. The work was partially done in conjunction with the Environmental Protection Agency assignments 'Assignment to provide input to a Swedish road map for Sweden without greenhouse gas emissions in 2050' as reported in December 2012. For a short-term development of the energy system the reader is referred to the Energy Authority's short-term forecasts that extend two to three years into the future and that are produced twice a year. Energy Agency's long-term projections are impact assessments with time horizon of 10-20 years which aims to describe the energy system's future development, provided a range of assumed conditions. If any of these conditions change it will also change forecast results. Economic development is an important assumption for the assessment of future energy.

  19. Climate and Long-Term Structures: The Wine-Harvesting Variable

    International Nuclear Information System (INIS)

    Le Roy Ladurie, Emmanuel

    2006-01-01

    Based on the history of wine harvests, it is possible to develop a more general history of climate, particularly in Europe. This history-the alternating cycle of warm and cool seasons-can also be related to the economic, and thus political, history of our countries, from the 14. century to the global warming of the 20. century. The role of the meteorologist in understanding these structures is therefore crucial

  20. Long-term retinal nerve fiber layer changes following nonarteritic anterior ischemic optic neuropathy

    Directory of Open Access Journals (Sweden)

    Dotan G

    2013-04-01

    Full Text Available Gad Dotan,1 Michaella Goldstein,1 Anat Kesler,1 Barry Skarf21Department of Ophthalmology, Tel Aviv Medical Center, Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv, Israel; 2Eye Care Services, Henry Ford Hospital, Detroit, MI, USABackground: In cases of nonarteritic anterior ischemic optic neuropathy (NAION, retinal nerve fiber layer (RNFL thickness changes have been described during the first 12 months following the acute event. The purpose of this study was to report on the long-term RNFL changes in these eyes beyond the first year following onset of NAION.Methods: Fourteen eyes of 13 patients with NAION were analyzed in this retrospective observational case series study. Uninvolved eyes served as controls. All patients underwent a complete neuro-ophthalmological examination and repeat measurements of peripapillary RNFL thickness using Stratus optical coherence tomography.Results: On optical coherence tomography scan performed on average 6 months following onset of NAION, the mean global RNFL thickness (59.8 ± 11.8 μm was significantly thinner (P < 0.001 compared with uninvolved eyes (95.1 ± 13.9 μm. In a second optical coherence tomography scan performed on average 13 (range 12–23 months later, the mean global RNFL thickness (58.9 ± 6.5 μm was not significantly different (P = 0.702 from the first scan.Conclusion: There appears to be no further RNFL loss beyond the first 6 months following an acute event of NAION.Keywords: optical coherence tomography, retinal nerve fiber layer, nonartertic anterior ischemic optic neuropathy

  1. Changes in body mass index in long-term childhood cancer survivors.

    Science.gov (United States)

    van Santen, Hanneke M; Geskus, Ronald B; Raemaekers, Steven; van Trotsenburg, A S Paul; Vulsma, Thomas; van der Pal, Helena J H; Caron, Hubert N; Kremer, Leontien C M

    2015-12-01

    Previous studies have reported changes in the body mass index (BMI) with time in childhood cancer survivors (CCSs) during follow-up. The limitations of these studies include that they described only a subgroup of survivors or used questionnaires with self-reported heights and weights. The goal of this study was to examine BMI in a large cohort of long-term CCSs and relate this to the BMI at diagnosis, age, sex, tumor type, treatment, and endocrine defects. All patients treated for childhood cancer at the Emma Children's Hospital/Academic Medical Center between 1966 and 1996 who had survived for at least 5 years were eligible for inclusion. For 893 CCSs with a mean follow-up of 14.9 years, the BMI at the late effects outpatient clinic was compared with the BMI for the general Dutch population. For girls, an increased prevalence of obesity was found. Risk factors for developing a high BMI at follow-up were a younger age and a high BMI at diagnosis and treatment with cranial radiotherapy. A significantly increased prevalence of severe underweight was found in all adult subgroups except for females aged 26 to 45 years. An association was found between a low BMI at diagnosis and a low BMI at follow-up. No treatment-related variables could be related to changes in BMI. The BMI at diagnosis is one of the most important predictors for the BMI at follow-up, and this suggests an important genetic or environmental cause. Adult CCSs are at high risk for developing severe underweight at follow-up. Future studies should focus on the causes and clinical consequences of underweight. © 2015 American Cancer Society.

  2. Long-term ERT monitoring of biogeochemical changes of an aged hydrocarbon contamination.

    Science.gov (United States)

    Caterina, David; Flores Orozco, Adrian; Nguyen, Frédéric

    2017-06-01

    Adequate management of contaminated sites requires information with improved spatio-temporal resolution, in particular to assess bio-geochemical processes, such as the transformation and degradation of contaminants, precipitation of minerals or changes in groundwater geochemistry occurring during and after remediation procedures. Electrical Resistivity Tomography (ERT), a geophysical method sensitive to pore-fluid and pore-geometry properties, permits to gain quasi-continuous information about subsurface properties in real-time and has been consequently widely used for the characterization of hydrocarbon-impacted sediments. However, its application for the long-term monitoring of processes accompanying natural or engineered bioremediation is still difficult due to the poor understanding of the role that biogeochemical processes play in the electrical signatures. For in-situ studies, the task is further complicated by the variable signal-to-noise ratio and the variations of environmental parameters leading to resolution changes in the electrical images. In this work, we present ERT imaging results for data collected over a period of two years on a site affected by a diesel fuel contamination and undergoing bioremediation. We report low electrical resistivity anomalies in areas associated to the highest contaminant concentrations likely due transformations of the contaminant due to microbial activity and accompanying release of metabolic products. We also report large seasonal variations of the bulk electrical resistivity in the contaminated areas in correlation with temperature and groundwater level fluctuations. However, the amplitude of bulk electrical resistivity variations largely exceeds the amplitude expected given existing petrophysical models. Our results suggest that the variations in electrical properties are mainly controlled by microbial activity which in turn depends on soil temperature and hydrogeological conditions. Therefore, ERT can be suggested as

  3. Long-term ERT monitoring of biogeochemical changes of an aged hydrocarbon contamination

    Science.gov (United States)

    Caterina, David; Flores Orozco, Adrian; Nguyen, Frédéric

    2017-06-01

    Adequate management of contaminated sites requires information with improved spatio-temporal resolution, in particular to assess bio-geochemical processes, such as the transformation and degradation of contaminants, precipitation of minerals or changes in groundwater geochemistry occurring during and after remediation procedures. Electrical Resistivity Tomography (ERT), a geophysical method sensitive to pore-fluid and pore-geometry properties, permits to gain quasi-continuous information about subsurface properties in real-time and has been consequently widely used for the characterization of hydrocarbon-impacted sediments. However, its application for the long-term monitoring of processes accompanying natural or engineered bioremediation is still difficult due to the poor understanding of the role that biogeochemical processes play in the electrical signatures. For in-situ studies, the task is further complicated by the variable signal-to-noise ratio and the variations of environmental parameters leading to resolution changes in the electrical images. In this work, we present ERT imaging results for data collected over a period of two years on a site affected by a diesel fuel contamination and undergoing bioremediation. We report low electrical resistivity anomalies in areas associated to the highest contaminant concentrations likely due transformations of the contaminant due to microbial activity and accompanying release of metabolic products. We also report large seasonal variations of the bulk electrical resistivity in the contaminated areas in correlation with temperature and groundwater level fluctuations. However, the amplitude of bulk electrical resistivity variations largely exceeds the amplitude expected given existing petrophysical models. Our results suggest that the variations in electrical properties are mainly controlled by microbial activity which in turn depends on soil temperature and hydrogeological conditions. Therefore, ERT can be suggested as

  4. Climatic change

    International Nuclear Information System (INIS)

    Perthuis, Ch. de; Delbosc, A.

    2009-01-01

    Received ideas about climatic change are a mixture of right and wrong information. The authors use these ideas as starting points to shade light on what we really know and what we believe to know. The book is divided in three main chapters: should we act in front of climatic change? How can we efficiently act? How can we equitably act? For each chapter a series of received ideas is analyzed in order to find those which can usefully contribute to mitigate the environmental, economical and social impacts of climatic change. (J.S.)

  5. Climate change

    NARCIS (Netherlands)

    Marchal, V.; Dellink, R.; Vuuren, D.P. van; Clapp, C.; Chateau, J.; Magné, B.; Lanzi, E.; Vliet, J. van

    2012-01-01

    This chapter analyses the policy implications of the climate change challenge. Are current emission reduction pledges made in Copenhagen/Cancun enough to stabilise the climate and limit global average temperature increase to 2 oC? If not, what will the consequences be? What alternative growth

  6. Couverture dynamique optimale du risque de change de long terme pour une entreprise

    OpenAIRE

    Wojakowski, Rafal

    1997-01-01

    Chapter 1 : Optimal dynamic level risk hedging for a corporation. An optimal hedging of the exchange rate risk for a firm is considered. The concept of the long term exchange rate risk is defined by opposition to the classic exchange rate risk. The optimal hedge of the intertemporal long term exchange rate risk is derived by the method of stochastic optimal control, in a model where the exchange rate follows a Gaussian process with return to the level of parity. It is demonstrated that such a...

  7. Long-term flow forecasts based on climate and hydrologic modeling: Uruguay River basin

    Science.gov (United States)

    Tucci, Carlos Eduardo Morelli; Clarke, Robin Thomas; Collischonn, Walter; da Silva Dias, Pedro Leite; de Oliveira, Gilvan Sampaio

    2003-07-01

    This paper describes a procedure for predicting seasonal flow in the Rio Uruguay drainage basin (area 75,000 km2, lying in Brazilian territory), using sequences of future daily rainfall given by the global climate model (GCM) of the Brazilian agency for climate prediction (Centro de Previsão de Tempo e Clima, or CPTEC). Sequences of future daily rainfall given by this model were used as input to a rainfall-runoff model appropriate for large drainage basins. Forecasts of flow in the Rio Uruguay were made for the period 1995-2001 of the full record, which began in 1940. Analysis showed that GCM forecasts underestimated rainfall over almost all the basin, particularly in winter, although interannual variability in regional rainfall was reproduced relatively well. A statistical procedure was used to correct for the underestimation of rainfall. When the corrected rainfall sequences were transformed to flow by the hydrologic model, forecasts of flow in the Rio Uruguay basin were better than forecasts based on historic mean or median flows by 37% for monthly flows and by 54% for 3-monthly flows.

  8. Behavior Change Strategies for Successful Long-Term Weight Loss: Focusing on Dietary and Physical Activity Adherence, Not Weight Loss

    Science.gov (United States)

    Hongu, Nobuko; Kataura, Martha P.; Block, Linda M.

    2011-01-01

    This article helps Extension professionals guide individuals in a successful long-term weight loss program. A program should focus on behavioral changes (improving eating habits and physical activity), not just weight loss. In order to do this, Extension professionals should implement behavior change strategies that motivate individuals to…

  9. Long-term occlusal changes assessed by the American Board of Orthodontics' model grading system.

    Science.gov (United States)

    Aszkler, Robert M; Preston, Charles B; Saltaji, Humam; Tabbaa, Sawsan

    2014-02-01

    The purpose of this study was to assess the long-term posttreatment changes in all criteria of the American Board of Orthodontics' (ABO) model grading system. We used plaster models from patients' final and posttreatment records. Thirty patients treated by 1 orthodontist using 1 bracket prescription were selected. An initial discrepancy index for each subject was performed to determine the complexity of each case. The final models were then graded using the ABO's model grading system immediately at posttreatment and postretention. Statistical analysis was performed on the 8 criteria of the model grading system, including paired t tests and Pearson correlations. An alpha of 0.05 was considered statistically significant. The average length of time between the posttreatment and postretention records was 12.7 ± 4.4 years. It was shown that alignment and rotations worsened by postretention (P = 0.014), and a weak statistically significant correlation at posttreatment and postretention was found (0.44; P = 0.016). Both marginal ridges and occlusal contacts scored less well at posttreatment. These criteria showed a significant decrease in scores between posttreatment and postretention (P <0.001), but the correlations were not statistically significant. The average total score showed a significant decrease between posttreatment and postretention (P <0.001), partly because of the large decrease in the previous 2 criteria. Higher scores for occlusal contacts and marginal ridges were found at the end of treatment; however, those scores and the overall scores for the 30 subjects improved in the postretention phase. Copyright © 2014. Published by Mosby, Inc.

  10. Lipidomic changes in rat liver after long-term exposure to ethanol

    International Nuclear Information System (INIS)

    Fernando, Harshica; Bhopale, Kamlesh K.; Kondraganti, Shakuntala; Kaphalia, Bhupendra S.; Shakeel Ansari, G.A.

    2011-01-01

    Alcoholic liver disease (ALD) is a serious health problem with significant morbidity and mortality. In this study we examined the progression of ALD along with lipidomic changes in rats fed ethanol for 2 and 3 months to understand the mechanism, and identify possible biomarkers. Male Fischer 344 rats were fed 5% ethanol or caloric equivalent of maltose-dextrin in a Lieber-DeCarli diet. Animals were killed at the end of 2 and 3 months and plasma and livers were collected. Portions of the liver were fixed for histological and immunohistological studies. Plasma and the liver lipids were extracted and analyzed by nuclear magnetic resonance (NMR) spectroscopy. A time dependent fatty infiltration was observed in the livers of ethanol-fed rats. Mild inflammation and oxidative stress were observed in some ethanol-fed rats at 3 months. The multivariate and principal component analysis of proton and phosphorus NMR spectroscopy data of extracted lipids from the plasma and livers showed segregation of ethanol-fed groups from the pair-fed controls. Significant hepatic lipids that were increased by ethanol exposure included fatty acids and triglycerides, whereas phosphatidylcholine (PC) decreased. However, both free fatty acids and PC decreased in the plasma. In liver lipids unsaturation of fatty acyl chains increased, contrary to plasma, where it decreased. Our studies confirm that over-accumulation of lipids in ethanol-induced liver steatosis accompanied by mild inflammation on long duration of ethanol exposure. Identified metabolic profile using NMR lipidomics could be further explored to establish biomarker signatures representing the etiopathogenesis, progression and/or severity of ALD. - Highlights: → Long term exposure to ethanol was studied. → A nuclear magnetic resonance (NMR) spectroscopy based lipidomic approach was used. → We examined the clustering pattern of the NMR data with principal component analysis. → NMR data were compared with histology and

  11. Long-term change analysis of satellite-based evapotranspiration over Indian vegetated surface

    Science.gov (United States)

    Gupta, Shweta; Bhattacharya, Bimal K.; Krishna, Akhouri P.

    2016-05-01

    In the present study, trend of satellite based annual evapotranspiration (ET) and natural forcing factors responsible for this were analyzed. Thirty years (1981-2010) of ET data at 0.08° grid resolution, generated over Indian region from opticalthermal observations from NOAA PAL and MODIS AQUA satellites, were used. Long-term data on gridded (0.5° x 0.5°) annual rainfall (RF), annual mean surface soil moisture (SSM) ERS scatterometer at 25 km resolution and annual mean incoming shortwave radiation from MERRA-2D reanalysis were also analyzed. Mann-Kendall tests were performed with time series data for trend analysis. Mean annual ET loss from Indian ago-ecosystem was found to be almost double (1100 Cubic Km) than Indian forest ecosystem (550 Cubic Km). Rainfed vegetation systems such as forest, rainfed cropland, grassland showed declining ET trend @ - 4.8, -0.6 &-0.4 Cubic Kmyr-1, respectively during 30 years. Irrigated cropland initially showed ET decline upto 1995 @ -0.8 cubic Kmyr-1 which could possibly be due to solar dimming followed by increasing ET @ 0.9 cubic Kmyr-1 after 1995. A cross-over point was detected between forest ET decline and ET increase in irrigated cropland during 2008. During 2001-2010, the four agriculturally important Indian states eastern, central, western and southern showed significantly increasing ET trend with S-score of 15-25 and Z-score of 1.09-2.9. Increasing ET in western and southern states was found to be coupled with increase in annual rainfall and SSM. But in eastern and central states no significant trend in rainfall was observed though significant increase in ET was noticed. The study recommended to investigate the influence of anthropogenic factors such as increase in area under irrigation, increased use of water for irrigation through ground water pumping, change in cropping pattern and cultivars on increasing ET.

  12. Climate and the changing Sun

    International Nuclear Information System (INIS)

    Eddy, J.A.

    1977-01-01

    Long-term changes in the level of solar activity are found in historical records and in fossil radiocarbon in tree-rings. Typical of these changes are the Maunder Minimum (A.D. 1645-1715), the Spoerer Minimum (A.D. 1400-1510), and a Medieval Maximum (c. A.D. 1120-1280). Eighteen such features are identified in the tree-ring radiocarbon record of the past 7500 years and compared with a record of world climate. In every case when long-term solar activity falls, mid-latitude glaciers advance and climate colls; at times of high solar activity glaciers recede and climate warms. It is proposed that changes in the level of solar activity and in climate may have a common cause: slow changes in the solar constant, of about 1% amplitude. (Auth.)

  13. The long-term fate of permafrost peatlands under rapid climate warming

    DEFF Research Database (Denmark)

    Swindles, Graeme T.; Morris, Paul J.; Mullan, Donal

    2015-01-01

    Permafrost peatlands contain globally important amounts of soil organic carbon, owing to cold conditions which suppress anaerobic decomposition. However, climate warming and permafrost thaw threaten the stability of this carbon store. The ultimate fate of permafrost peatlands and their carbon...... stores is unclear because of complex feedbacks between peat accumulation, hydrology and vegetation. Field monitoring campaigns only span the last few decades and therefore provide an incomplete picture of permafrost peatland response to recent rapid warming. Here we use a high-resolution palaeoecological...... approach to understand the longer-term response of peatlands in contrasting states of permafrost degradation to recent rapid warming. At all sites we identify a drying trend until the late-twentieth century; however, two sites subsequently experienced a rapid shift to wetter conditions as permafrost thawed...

  14. Changes in microbial populations of WPC34 and WPC80 whey protein during long term storage

    Science.gov (United States)

    The use of whey protein (WPC34 and WPC80) as a food ingredient and as a base for making biodegradable products is increasing. The need to alleviate world hunger in arid and semi-arid regions demands that we investigate the behavior of native bacteria in these products, especially during long term st...

  15. Culture Change in Long Term Care Services: Eden-Greenhouse-Aging in the Community

    Science.gov (United States)

    Brune, Kendall

    2011-01-01

    To discuss the relationship between residents and the management team, we must first review the transition from a medical model to a social model of care that is sweeping across America. Long-term care (LTC) management models were developed for a very autocratic and hierarchical style of management based in the 1960s. Those facilities were built…

  16. Climate change research in Canada

    International Nuclear Information System (INIS)

    Dawson, K.

    1994-01-01

    The current consensus on climatic change in Canada is briefly summarized, noting the results of modelling of the effects of a doubling of atmospheric CO 2 , the nonuniformity of climate change across the country, the uncertainties in local responses to change, and the general agreement that 2-4 degrees of warming will occur for each doubling of CO 2 . Canadian government response includes programs aimed at reducing the uncertainties in the scientific understanding of climate change and in the socio-economic response to such change. Canadian climate change programs include participation in large-scale experiments on such topics as heat transport in the ocean, and sources and sinks of greenhouse gases; development of next-generation climate models; studying the social and economic effects of climate change in the Great Lakes Basin and Mackenzie River Basin; investigation of paleoclimates; and analysis of climate data for long-term trends

  17. What factors influence the effectiveness of financial incentives on long-term natural resource management practice change?

    Directory of Open Access Journals (Sweden)

    Emma Swann

    2016-12-01

    Full Text Available Financial incentives are used by natural resource management organisations to encourage landholders to adopt sustainable practices where the outcomes on a farm scale may be negative or marginal. There is a growing body of research aimed at understanding why landholders do or do not agree to participate in financial incentive programs, however research that considers when and how financial incentives work to bring about long-term behaviour change is relatively immature. The purpose of this review is to answer the question ‘What factors influence the effectiveness of financial incentives on long-term natural resource management practice change?’ In synthesising the evidence, it was found that there are numerous characteristics of the practice change itself, along with the program design and implementation, which are important to understand long-term behaviour change. These include whether inexpensive maintenance or long-term funding is available; whether the changes are relatively simple to sustain; whether the program involves structural changes; whether there is land use rigidity; and whether the changes have resulting environmental benefits that are highly observable. Additionally, it is advisable for programs that use financial incentives to include the following program features: ongoing extension support and a focus on building relationship and trust; flexibility in how the practice change is applied; active landholder involvement from planning to evaluation; and contract length that is appropriate for the complexity of the NRM practice. These characteristics can be used to guide policy makers in their natural resource management investment decisions. There is a clear need for greatly increased monitoring and evaluation of existing programs, both during the program and after its conclusion, in order to more fully understand its long-term impacts and ultimate effectiveness. Finally, landholders undertaking a practice change generally

  18. Microbial volatile organic compounds in moldy interiors: a long-term climate chamber study.

    Science.gov (United States)

    Schuchardt, Sven; Strube, Andrea

    2013-06-01

    The present study simulated large-scale indoor mold damage in order to test the efficiency of air sampling for the detection of microbial volatile organic compounds (MVOCs). To do this, a wallpaper damaged by condensation was stored in a climate chamber (representing a hypothetical test room of 40 m(3) volume) and was inoculated with 14 typical indoor fungal strains. The chamber ventilation conditions were adjusted to common values found in moldy homes, and the mold growth was allowed to continue to higher than average values. The MVOC content of the chamber air was analyzed daily for a period of 105 days using coupled gas chromatography/mass spectrometry (GC-MS). This procedure guarantees MVOC profiling without external factors such as outdoor air, building materials, furniture, and occupants. However, only nine MVOCs could be detected during the sampling period, which indicates that the very low concentrated MVOCs are hardly accessible, even under these favorable conditions. Furthermore, most of the MVOCs that were detected cannot be considered as reliable indicators of mold growth in indoor environments. © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  19. Long-term changes in flood event patterns due to changes in hydrological distribution parameters in a rural-urban catchment, Shikoku, Japan

    Science.gov (United States)

    Mouri, Goro; Kanae, Shinjiro; Oki, Taikan

    2011-07-01

    This article describes the principal control parameters of flood events and precipitation and the relationships between corresponding hydrologic and climatologic parameters. The long-term generation of runoff and associated processes is important in understanding floods and droughts under changes in climate and land use. This study presents detailed analyses of flood events in a coastal amphitheatre catchment with a total area of 445 km 2 in western Japan, followed by analyses of flood events in both urban and forest areas. Using long-term (1962 to 2002) hydrological and climatological data from the Ministry of Land, Infrastructure and Transport, Japan, the contributions of precipitation, river discharge, temperature, and relative humidity to flood events were analysed. Flood events could be divided into three types with respect to hydrologic and climatologic principal control parameters: the long-term tendency; medium-term changes as revealed by hydrographs and hyetographs of high-intensity events such as the relative precipitation, river discharge, and temperature; and large events, as shown by the flow-duration curve, with each cluster having particular characteristics. River discharge showed a decreasing tendency of flow quantity during small rainfall events of less than 100 mm/event from the 1980s to the present. An approximately 7% decrease from 44.8 to 37.3% occurred in the percentage of river water supplied by precipitation in the years after the 1980s. For the medium-term changes, no marked change occurred in the flow quantity of the peak point over time in event hydrographs. However, flow quantities before and after the peak tended to decrease by 1 to 2 m 3/s after the 1980s. Theoretical considerations with regard to the influence of hydrologic and climatologic parameters on flood discharge are discussed and examined in terms of observational data. These findings provide a sound foundation for use in hydrological catchment modelling.

  20. Non-Psychrophilic Methanogens Capable of Growth Following Long-Term Extreme Temperature Changes, with Application to Mars

    Directory of Open Access Journals (Sweden)

    Rebecca L. Mickol

    2018-04-01

    Full Text Available Although the martian environment is currently cold and dry, geomorphological features on the surface of the planet indicate relatively recent (<4 My freeze/thaw episodes. Additionally, the recent detections of near-subsurface ice as well as hydrated salts within recurring slope lineae suggest potentially habitable micro-environments within the martian subsurface. On Earth, microbial communities are often active at sub-freezing temperatures within permafrost, especially within the active layer, which experiences large ranges in temperature. With warming global temperatures, the effect of thawing permafrost communities on the release of greenhouse gases such as carbon dioxide and methane becomes increasingly important. Studies examining the community structure and activity of microbial permafrost communities on Earth can also be related to martian permafrost environments, should life have developed on the planet. Here, two non-psychrophilic methanogens, Methanobacterium formicicum and Methanothermobacter wolfeii, were tested for their ability to survive long-term (~4 year exposure to freeze/thaw cycles varying in both temperature and duration, with implications both for climate change on Earth and possible life on Mars.

  1. Non-Psychrophilic Methanogens Capable of Growth Following Long-Term Extreme Temperature Changes, with Application to Mars.

    Science.gov (United States)

    Mickol, Rebecca L; Laird, Sarah K; Kral, Timothy A

    2018-04-23

    Although the martian environment is currently cold and dry, geomorphological features on the surface of the planet indicate relatively recent (<4 My) freeze/thaw episodes. Additionally, the recent detections of near-subsurface ice as well as hydrated salts within recurring slope lineae suggest potentially habitable micro-environments within the martian subsurface. On Earth, microbial communities are often active at sub-freezing temperatures within permafrost, especially within the active layer, which experiences large ranges in temperature. With warming global temperatures, the effect of thawing permafrost communities on the release of greenhouse gases such as carbon dioxide and methane becomes increasingly important. Studies examining the community structure and activity of microbial permafrost communities on Earth can also be related to martian permafrost environments, should life have developed on the planet. Here, two non-psychrophilic methanogens, Methanobacterium formicicum and Methanothermobacter wolfeii , were tested for their ability to survive long-term (~4 year) exposure to freeze/thaw cycles varying in both temperature and duration, with implications both for climate change on Earth and possible life on Mars.

  2. Long-term changes in net radiation and its components above a pine forest and a grass surface in Germany

    International Nuclear Information System (INIS)

    Kessler, A.; Jaeger, L.

    1999-01-01

    Long-term measurements (1974–1993 and 1996, respectively) of the net radiation (Q), global radiation (G), reflected global radiation (R), long-wave atmospheric radiation (A) and thermal radiation (E) of a pine forest in Southern Germany (index p) and of a grass surface in Northern Germany (index g) are compared. The influence of changes in surface properties is discussed. There are, in the case of the pine stand, forest growth and forest management and in the case of the grass surface, the shifting of the site from a climatic garden to a horizontal roof. Both series of radiant fluxes are analyzed with respect to the influences of the weather (cloudiness, heat advection). To eliminate the different influence of the solar radiation of the two sites, it is necessary to normalize by means of the global radiation G, yielding the radiation efficiency Q/G, the albedo R/G=α and the normalized long-wave net radiation (A+E)/G. Furthermore, the long-term mean values and the long-term trend of yearly mean values are discussed and, moreover, a comparison is made of individual monthly values. Q p is twice as large as Q g . The reason for this is the higher values of G and A above the pine forest and half values of α p compared to α g . E p is only a little greater than E g . The time series of the radiation fluxes show the following trends: Q p declines continuously despite a slight increase of G p . This is mainly due to the long-wave radiation fluxes. The net radiation of the grass surface Q g shows noticeably lower values after the merging of the site. This phenomenon is also dominated by the long-wave radiation processes. Although the properties of both site surfaces alter, E p and E g remain relatively stable. A p and A g show a remarkable decrease however. The reason for this is to be found in a modification of the heat advection, showing a more pronounced impact on the more continentally exposed site (pine forest). Compared to α g , α p shows only a small

  3. The long term response of stream flow to climatic warming in headwater streams of interior Alaska

    Science.gov (United States)

    Jeremy B. Jones; Amanda J. Rinehart

    2010-01-01

    Warming in the boreal forest of interior Alaska will have fundamental impacts on stream ecosystems through changes in stream hydrology resulting from upslope loss of permafrost, alteration of availability of soil moisture, and the distribution of vegetation. We examined stream flow in three headwater streams of the Caribou-Poker Creeks Research Watershed (CPCRW) in...

  4. Long-term soil warming and Carbon Cycle Feedbacks to the Climate System

    Energy Technology Data Exchange (ETDEWEB)

    Melillo, Jerry M.

    2014-04-30

    The primary objective of the proposed research was to quantify and explain the effects of a sustained in situ 5oC soil temperature increase on net carbon (C) storage in a northeastern deciduous forest ecosystem. The research was done at an established soil warming experiment at the Harvard Forest in central Massachusetts – Barre Woods site established in 2001. In the field, a series of plant and soil measurements were made to quantify changes in C storage in the ecosystem and to provide insights into the possible relationships between C-storage changes and nitrogen (N) cycling changes in the warmed plots. Field measurements included: 1) annual woody increment; 2) litterfall; 3) carbon dioxide (CO2) efflux from the soil surface; 4) root biomass and respiration; 5) microbial biomass; and 6) net N mineralization and net nitrification rates. This research was designed to increase our understanding of how global warming will affect the capacity of temperate forest ecosystems to store C. The work explored how soil warming changes the interactions between the C and N cycles, and how these changes affect land-atmosphere feedbacks. This core research question framed the project – What are the effects of a sustained in situ 5oC soil temperature increase on net carbon (C) storage in a northeastern deciduous forest ecosystem? A second critical question was addressed in this research – What are the effects of a sustained in situ 5{degrees}C soil temperature increase on nitrogen (N) cycling in a northeastern deciduous forest ecosystem?

  5. Long term, non-anthropogenic groundwater storage changes simulated by a global land surface model

    Science.gov (United States)

    Li, B.; Rodell, M.; Sheffield, J.; Wood, E. F.

    2017-12-01

    Groundwater is crucial for meeting agricultural, industrial and municipal water needs, especially in arid, semi-arid and drought impacted regions. Yet, knowledge on groundwater response to climate variability is not well understood due to lack of systematic and continuous in situ measurements. In this study, we investigate global non-anthropogenic groundwater storage variations with a land surface model driven by a 67-year (1948-204) meteorological forcing data set. Model estimates were evaluated using in situ groundwater data from the central and northeastern U.S. and terrestrial water storage derived from the Gravity Recovery and Climate Experiment (GRACE) satellites and found to be reasonable. Empirical orthogonal function (EOF) analysis was employed to examine modes of variability of groundwater storage and their relationship with atmospheric effects such as precipitation and evapotranspiration. The result shows that the leading mode in global groundwater storage reflects the influence of the El Niño Southern Oscillation (ENSO). Consistent with the EOF analysis, global total groundwater storage reflected the low frequency variability of ENSO and decreased significantly over 1948-2014 while global ET and precipitation did not exhibit statistically significant trends. This study suggests that while precipitation and ET are the primary drivers of climate related groundwater variability, changes in other forcing fields than precipitation and temperature are also important because of their influence on ET. We discuss the need to improve model physics and to continuously validate model estimates and forcing data for future studies.

  6. Long-term change in limnology and invertebrates in Alaskan boreal wetlands

    Science.gov (United States)

    Corcoran, R.M.; Lovvorn, J.R.; Heglund, P.J.

    2009-01-01

    Climate change is more pronounced at high northern latitudes, and may be affecting the physical, chemical, and biological attributes of the abundant wetlands in boreal forests. On the Yukon Flats, located in the boreal forest of northeast Alaska, wetlands originally sampled during 1985-1989 were re-sampled for water chemistry and macroinvertebrates in summer 2001-2003. Wetlands sampled lost on average 19% surface water area between these periods. Total nitrogen and most metal cations (Na, Mg, and Ca, but not K) increased between these periods, whereas total phosphorus and chlorophyll a (Chl a) declined. These changes were greater in wetlands that had experienced more drying (decreased surface area). Compared with 1985-1989, densities of cladocerans, copepods, and ostracods in both June and August were much higher in 2002-2003, whereas densities of amphipods, gastropods, and chironomid larvae were generally lower. In comparisons among wetlands in 2002-2003 only, amphipod biomass was lower in wetlands with lower Chl a, which might help explain the decline of amphipods since the late 1980s when Chl a was higher. The decline in Chl a corresponded to greatly increased zooplankton density in June, suggesting a shift in carbon flow from scrapers and deposit-feeders to water-column grazers. Declines in benthic and epibenthic deposit-feeding invertebrates suggest important food web effects of climate change in otherwise pristine wetlands of the boreal forest. ?? 2008 Springer Science+Business Media B.V.

  7. Non-stationarity driven by long-term change in catchment storage: possibilities and implications

    Directory of Open Access Journals (Sweden)

    J. D. Hughes

    2015-06-01

    Full Text Available "Non-stationarity" with reference to hydrology is a term applied to many situations (Milly et al., 2008. While climate change non-stationarity is often examined, these effects can provide a test for assumptions of runoff generation process impliedin rainfall–runoff (RR models. Observations from South-western Australia (SWA over the past 40 years show a decline in rainfall and reductions in runoff. Runoff and rainfall relationships in SWA show a significant shift over the past 40 years suggesting a change in runoff generation and catchment state. This has challenged the nature of assumed runoff generation process in SWA as well as the veracity of conceptual RR model structure. We expand on some of the lessons learned from SWA and discuss the climatic and geomorphic conditions that may make reasonable predictions of runoff very difficult with RR models calibrated in traditional ways. Catchment storage has a significant interaction with runoff generation and we examine the situations where these may change in the longer term. We suggest some strategies in terms of model structure and calibration that may improve predictive performance in such situations.

  8. Long-term landscape changes in a subalpine spruce-fir forest in central Utah, USA

    Directory of Open Access Journals (Sweden)

    Jesse L. Morris1

    2015-12-01

    Full Text Available Background: In Western North America, increasing wildfire and outbreaks of native bark beetles have been mediated by warming climate conditions. Bioclimatic models forecast the loss of key high elevation species throughout the region. This study uses retrospective vegetation and fire history data to reconstruct the drivers of past disturbance and environmental change. Understanding the relationship among climate, antecedent disturbances, and the legacy effects of settlement-era logging can help identify the patterns and processes that create landscapes susceptible to bark beetle epidemics. Methods: Our analysis uses data from lake sediment cores, stand inventories, and historical records. Sediment cores were dated with radiometric techniques (14C and 210Pb/137Cs and subsampled for pollen and charcoal to maximize the temporal resolution during the historical period (1800 CE to present and to provide environmental baseline data (last 10,500 years. Pollen data for spruce were calibrated to carbon biomass (C t/ha using standard allometric equations and a transfer function. Charcoal samples were analyzed with statistical models to facilitate peak detection and determine fire recurrence intervals. Results: The Wasatch Plateau has been dominated by Engelmann spruce forests for the last ~10,500 years, with subalpine fir becoming more prominent since 6000 years ago. This landscape has experienced a dynamic fire regime, where burning events are more frequent and of higher magnitude during the last 3000 years. Two important disturbances have impacted Engelmann spruce in the historical period: 1 high-grade logging during the late 19th century; and (2 a high severity spruce beetle outbreak in the late 20th century that killed >90 % of mature spruce (>10 cm dbh. Conclusions: Our study shows that spruce-dominated forests in this region are resilient to a range of climate and disturbance regimes. Several lines of evidence suggest that 19th century logging

  9. Climate change. Managing the risks

    International Nuclear Information System (INIS)

    Swart, R.J.

    1994-01-01

    In order to address the key question if a targeted approach to climate change response is feasible, different aspects of this question are analyzed. First, the scientific and political aspects of different options to determine specific long-term objectives for climate change are evaluated on the basis of the current scientific insights and the experiences over the last 5 years to develop climate objectives. Preliminary directions for such objectives are given. Next, important analytical tools are discussed that can be applied to analyze the different options and their implications in detail. In order to evaluate the implications of mitigation options, strategies that are consistent with the preliminary climate goals are analyzed in the third part. In chapter 2, the concept of long-term environmental goals, derived from critical levels of climate change, is discussed. Also a historical perspective is provided. A new, systematic regionalized and risk-based approach to elaborate the ultimate objective of the Framework Convention on Climate Change is proposed. In chapter 3 scenarios and integrated models are discussed. Central is the description of scenarios that were developed with RlVM's Integrated Model to Assess the Greenhouse Effect (IMAGE) and the US-EPA's Atmospheric Stabilization Framework (ASF). In chapter 4 potential long-term international emissions control strategies for the different sources and sinks of the most important greenhouse gases are analyzed. Carbon dioxide from energy, carbon dioxide from deforestation, and non-CO 2 greenhouse gases are dealt with subsequently. The dissertation ends with general conclusions and recommendations for the further design of a targeted approach to climate change response, the development of analytical tools to support policy development in the area of climate change, and strategies that are consistent with preliminary long-term environmental goals. 66 figs., 8 tabs., 417 refs., 1 appendix

  10. Climatic change

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1977-02-15

    In spite of man's remarkable advances in technology, ultimately he is still dependent on the Earth's climatic system for food and fresh water. The recent occurrences in certain regions of the world of climatic extremes such as excessive rain or droughts and unseasonably high or low temperatures have led to speculation that a major climatic change is occurring on a global scale. Some point to the recent drop in temperatures in the northern hemisphere as an indication that the Earth is entering a new ice age. Others see a global warming trend that may be due to a build-up of carbon dioxide in the atmosphere. An authoritative report on the subject has been prepared by a World Meteorological Organization Panel of Experts on Climatic Change. Excerpts from the report are given. (author)

  11. Climatic change

    International Nuclear Information System (INIS)

    1977-01-01

    In spite of man's remarkable advances in technology, ultimately he is still dependent on the Earth's climatic system for food and fresh water. The recent occurrences in certain regions of the world of climatic extremes such as excessive rain or droughts and unseasonably high or low temperatures have led to speculation that a major climatic change is occurring on a global scale. Some point to the recent drop in temperatures in the northern hemisphere as an indication that the Earth is entering a new ice age. Others see a global warming trend that may be due to a build-up of carbon dioxide in the atmosphere. An authoritative report on the subject has been prepared by a World Meteorological Organization Panel of Experts on Climatic Change. Excerpts from the report are given. (author)

  12. Long-term changes of tropospheric NO2 over megacities derived from multiple satellite instruments

    Directory of Open Access Journals (Sweden)

    A. Hilboll

    2013-04-01

    Full Text Available Tropospheric NO2, a key pollutant in particular in cities, has been measured from space since the mid-1990s by the GOME, SCIAMACHY, OMI, and GOME-2 instruments. These data provide a unique global long-term dataset of tropospheric pollution. However, the observations differ in spatial resolution, local time of measurement, viewing geometry, and other details. All these factors can severely impact the retrieved NO2 columns. In this study, we present three ways to account for instrumental differences in trend analyses of the NO2 columns derived from satellite measurements, while preserving the individual instruments' spatial resolutions. For combining measurements from GOME and SCIAMACHY into one consistent time series, we develop a method to explicitly account for the instruments' difference in ground pixel size (40 × 320 km2 vs. 30 × 60 km2. This is especially important when analysing NO2 changes over small, localised sources like, e.g. megacities. The method is based on spatial averaging of the measured earthshine spectra and extraction of a spatial pattern of the resolution effect. Furthermore, two empirical corrections, which summarise all instrumental differences by including instrument-dependent offsets in a fitted trend function, are developed. These methods are applied to data from GOME and SCIAMACHY separately, to the combined time series, and to an extended dataset comprising also GOME-2 and OMI measurements. All approaches show consistent trends of tropospheric NO2 for a selection of areas on both regional and city scales, for the first time allowing consistent trend analysis of the full time series at high spatial resolution. Compared to previous studies, the longer study period leads to significantly reduced uncertainties. We show that measured tropospheric NO2 columns have been strongly increasing over China, the Middle East, and India, with values over east-central China tripling from 1996 to 2011. All parts of the developed world

  13. Study of long term structural and functional changes in medically controlled glaucoma

    Directory of Open Access Journals (Sweden)

    Achyut N Pandey

    2014-02-01

    Full Text Available AIM:Prospectively analyze the long term structural and functional changes in patients of primary open angle glaucoma (POAG receiving medical therapy (beta blockers and non beta blockers. In this study an attempt has been made to evaluate whether medical reduction of IOP prevents or delays the progression of glaucomatous visual field loss and/or optic nerve damage in patients with open angle glaucoma.METHODS:Study conducted over a period of 27 months, at a tertiary eye care hospital including both eyes of 40 patients with POAG. Group 1 (20 patients, 40 eyes received beta-blockers, and Group 2 (20 patients, 40 eyes received non-beta-blockers. Each patient underwent intraocular pressure measurement, best corrected visual acuity, slit-lamp, fundus examination, gonioscopy, central corneal thickness, visual field assessment by Humphrey automated perimetry and retinal nerve fibre layer thickness by Stratus optical coherence tomography at baseline and at two subsequent visits. The average time interval between each visit was 10-11 months. The statistical analysis was done using one-way analysis of variance (ANOVA. Post-hoc test, using tukey’ method were adopted. Probablity (P value of 0.05 or less was considered to be statistically significant.RESULTS:A total of 80 eyes of 40 patients of POAG were enrolled, 24 males, 16 females, age group 50-80 years. In both beta and non beta blocker group, reduction (improvement in mean IOP from initial levels to the levels achieved at the 2nd and 3rd visits was statistically significant. One way ANOVA (df=2, fisher f value=11.64, P=0.000, one way ANOVA (df=3, fisher f value=35.61, P=0.000. Both mean deviation (MD and pattern standard deviation (PSD in both beta and non beta blockers at different visits were not statistically significant. Retinal nerve fibre layer thickness (RNFL -only mean inferior retinal nerve fibre layer, the difference between the mean value in beta and non beta blocker groupwere statistically

  14. Long-Term Changes of Tropospheric Trace Gases over Pakistan Derived From Multiple Satellite Instruments

    Science.gov (United States)

    Zeb, Naila; Fahim Khokhar, Muhammad; Murtaza, Rabbia; Noreen, Asma; Khalid, Tameem

    2016-07-01

    Air pollution is the expected key environmental issue of Pakistan in coming years due to its ongoing rapid economic growth and this trend suggests only worst air quality over time. In 2014, World bank reported the Pakistan's urban air quality among the most severe in the world and intimated the government to make improvement in air quality as a priority policy agenda. In addition it is recommended to strengthen the institutional and technical capacity of organizations responsible for air quality management. Therefore, the study is designed to put efforts in highlighting air quality issues. The study will provide first database for tropospheric trace gases over Pakistan. The study aims to analyse tropospheric concentrations of CO, TOC, NO2 and HCHO over Pakistan using multisensory data from January 2005 to January 2014. Spatio-temporal and seasonal variability of tropospheric trace gases is observed over the decade to explore long term trend. Hotspots are identified to see variation of species with latitude and to highlight possible sources of trace gases over the Pakistan. High concentrations of trace gases are mainly observed over the Punjab region, which may be attributed to its metropolitan importance. It is the major agricultural, industrialized and urbanized (nearly 60% of the Pakistan's population) sector of the country. Overall significant decreasing trend of CO is identified by MOPITT with relative change of 12.4%. Tropospheric ozone column (TOC) showed insignificant increasing trend with temporal increase of 10.4% whereas NO2 exhibited a significant temporal increase of about 28%. For formaldehyde (HCHO), an increase of about 3.8% is calculated for SCIAMACHY data. Well defined seasonal cycles for these trace gases are observed over the whole study period. CO concentrations showed peak in winter months (November/December/January/February) and dip in the months of Summer/Monsoon (June/July/August). In spite of CO, TCO increases gradually in March and peaks

  15. Changes in the long-term delayed response of platinum self-powered detector with irradiation

    International Nuclear Information System (INIS)

    Parent, G.; Serdula, K.J.; Eng, P.

    1989-01-01

    Two long-term delayed response characteristics have been observed for platinum, Pt, detectors in the Gentilly-2 600 MW(e) CANDU PHWR reactor. The first effect is a dip in the signal two to three hours after a shutdown, due to the (n,beta) interactions of Mn-55 and Ni-64 which exist as impurities in the detector assembly. The second effect is an increase of the delayed fraction of the signal. The low neutron absorption cross-section of Pt-196 combined with the conversion of the Pt-194 and Pt-195 results in build-up of the Pt-196. The long half-lives associated with the beta-emission in the transmutation of Pt-196 to Hg-198 or Hg-199 give rise to the observed long-term delayed response

  16. Accelerated long-term assessment of thermal and chemical stability of bio-based phase change materials

    Science.gov (United States)

    Thermal energy storage (TES) systems incorporated with phase change materials (PCMs) have potential applications to control energy use by building envelopes. However, it is essential to evaluate long term performance of the PCMs and cost effectiveness prior to full scale implementation. For this rea...

  17. 78 FR 32001 - Public Notice for a Change in Use of Aeronautical Property and Long-Term Lease Approval at...

    Science.gov (United States)

    2013-05-28

    ... International Airport approved Airport Layout Plan (ALP). There is to be no sale or transfer of property rights... DEPARTMENT OF TRANSPORTATION Federal Aviation Administration Public Notice for a Change in Use of Aeronautical Property and Long-Term Lease Approval at Harrisburg International Airport (MDT), Middletown, PA...

  18. The analysis of long-term changes in plant communities using large databases: the effect of stratified resampling.

    NARCIS (Netherlands)

    Haveman, R.; Janssen, J.A.M.

    2008-01-01

    Question: Releves in large phytosociological databases used for analysing long-term changes in plant communities are biased towards easily accessible places and species-rich stands. How does this bias influence trend analysis of floristic composition within a priori determined vegetation types and

  19. Long-term outcome of biopsy-proven, frequently relapsing minimal-change nephrotic syndrome in children.

    NARCIS (Netherlands)

    Kyrieleis, H.A.; Lowik, M.M.; Pronk, I.; Cruysberg, J.R.M.; Kremer, J.A.M.; Oyen, W.J.G.; Heuvel, L.P.W.J. van den; Wetzels, J.F.M.; Levtchenko, E.N.

    2009-01-01

    BACKGROUND AND OBJECTIVES: Frequently relapsing and steroid-dependent minimal-change nephrotic syndrome (MCNS) that originates in childhood can persist after puberty in >20% of patients. These patients require immunosuppressive treatment during several decades of their life. We examined long-term

  20. Mapping Long-Term Changes in Mangrove Species Composition and Distribution in the Sundarbans

    Directory of Open Access Journals (Sweden)

    Manoj Kumer Ghosh

    2016-12-01

    Full Text Available The Sundarbans mangrove forest is an important resource for the people of the Ganges Delta. It plays an important role in the local as well as global ecosystem by absorbing carbon dioxide and other pollutants from air and water, offering protection to millions of people in the Ganges Delta against cyclone and water surges, stabilizing the shore line, trapping sediment and nutrients, purifying water, and providing services for human beings, such as fuel wood, medicine, food, and construction materials. However, this mangrove ecosystem is under threat, mainly due to climate change and anthropogenic factors. Anthropogenic and climate change-induced degradation, such as over-exploitation of timber and pollution, sea level rise, coastal erosion, increasing salinity, effects of increasing number of cyclones and higher levels of storm surges function as recurrent threats to mangroves in the Sundarbans. In this situation, regular and detailed information on mangrove species composition, their spatial distribution and the changes taking place over time is very important for a thorough understanding of mangrove biodiversity, and this information can also lead to the adoption of management practices designed for the maximum sustainable yield of the Sundarbans forest resources. We employed a maximum likelihood classifier technique to classify images recorded by the Landsat satellite series and used post classification comparison techniques to detect changes at the species level. The image classification resulted in overall accuracies of 72%, 83%, 79% and 89% for the images of 1977, 1989, 2000 and 2015, respectively. We identified five major mangrove species and detected changes over the 38-year (1977–2015 study period. During this period, both Heritiera fomes and Excoecaria agallocha decreased by 9.9%, while Ceriops decandra, Sonneratia apelatala, and Xylocarpus mekongensis increased by 12.9%, 380.4% and 57.3%, respectively.

  1. Norway spruce crown structure changes under long-term multiple stress impact in Central European Mts

    Czech Academy of Sciences Publication Activity Database

    Moravec, Ivo; Cudlín, Pavel; Polák, T.

    2003-01-01

    Roč. 22, Suppl. 1 (2003), s. 252-255 ISSN 1335-342X. [Long Term Air Pollution Effect on Forest Ecosystems (International Meeting for Specialists in Air Pollution Effects on Forest Ecosystems)/20./. Zvolen, 30.08.2002-01.09.2002] R&D Projects: GA MŠk OK 355 Institutional research plan: CEZ:AV0Z6087904 Keywords : Norway spruce * crown transformation * tree status Subject RIV: EH - Ecology, Behaviour Impact factor: 0.100, year: 2003

  2. The changes in perception of visual illusions during long-term isolation

    Czech Academy of Sciences Publication Activity Database

    Šikl, Radovan; Šimeček, Michal; Lukavský, Jiří

    2009-01-01

    Roč. 2009, č. 38 (2009), s. 31-32 ISSN 0301-0066. [European Conference on Visual Perception. 24.08.2009-28.08.2009, Regensburg] R&D Projects: GA ČR GA406/09/2003 Institutional research plan: CEZ:AV0Z70250504 Keywords : long-term isolation * geometrical illusions * perspective Subject RIV: AN - Psychology http://www.perceptionweb.com/abstract.cgi?id=v090766

  3. Long-term temporal changes in central European tree phenology (1946-2010) confirm the recent extension of growing seasons

    Science.gov (United States)

    Kolářová, Eva; Nekovář, Jiří; Adamík, Peter

    2014-10-01

    One of the ways to assess the impacts of climate change on plants is analysing their long-term phenological data. We studied phenological records of 18 common tree species and their 8 phenological phases, spanning 65 years (1946-2010) and covering the area of the Czech Republic. For each species and phenophase, we assessed the changes in its annual means (for detecting shifts in the timing of the event) and standard deviations (for detecting changes in duration of the phenophases). The prevailing pattern across tree species was that since around the year 1976, there has been a consistent advancement of the onset of spring phenophases (leaf unfolding and flowering) and subsequent acceleration of fruit ripening, and a delay of autumn phenophases (leaf colouring and leaf falling). The most considerable shifts in the timing of spring phenophases were displayed by early-successional short-lived tree species. The most pronounced temporal shifts were found for the beginning of seed ripening in conifers with an advancement in this phenophase of up to 2.2 days year-1 in Scots Pine ( Pinus sylvestris). With regards to the change in duration of the phenophases, no consistent patterns were revealed. The growing season has extended on average by 23.8 days during the last 35 years. The most considerable prolongation was found in Pedunculate Oak ( Quercus robur): 31.6 days (1976-2010). Extended growing season lengths do have the potential to increase growth and seed productivity, but unequal shifts among species might alter competitive relationships within ecosystems.

  4. Long-term Satellite NDVI Data Sets: Evaluating Their Ability to Detect Ecosystem Functional Changes in South America.

    Science.gov (United States)

    Baldi, Germán; Nosetto, Marcelo D; Aragón, Roxana; Aversa, Fernando; Paruelo, José M; Jobbágy, Esteban G

    2008-09-03

    In the last decades, South American ecosystems underwent important functional modifications due to climate alterations and direct human intervention on land use and land cover. Among remotely sensed data sets, NOAA-AVHRR "Normalized Difference Vegetation Index" (NDVI) represents one of the most powerful tools to evaluate these changes thanks to their extended temporal coverage. In this paper we explored the possibilities and limitations of three commonly used NOAA-AVHRR NDVI series (PAL, GIMMS and FASIR) to detect ecosystem functional changes in the South American continent. We performed pixel-based linear regressions for four NDVI variables (average annual, maximum annual, minimum annual and intra-annual coefficient of variation) for the 1982-1999 period and (1) analyzed the convergences and divergences of significant multi-annual trends identified across all series, (2) explored the degree of aggregation of the trends using the O-ring statistic, and (3) evaluated observed trends using independent information on ecosystem functional changes in five focal regions. Several differences arose in terms of the patterns of change (the sign, localization and total number of pixels with changes). FASIR presented the highest proportion of changing pixels (32.7%) and GIMMS the lowest (16.2%). PAL and FASIR data sets showed the highest agreement, with a convergence of detected trends on 71.2% of the pixels. Even though positive and negative changes showed substantial spatial aggregation, important differences in the scale of aggregation emerged among the series, with GIMMS showing the smaller scale (≤11 pixels). The independent evaluations suggest higher accuracy in the detection of ecosystem changes among PAL and FASIR series than with GIMMS, as they detected trends that match expected shifts. In fact, this last series eliminated most of the long term patterns over the continent. For example, in the "Eastern Paraguay" and "Uruguay River margins" focal regions, the

  5. Monitoring the long term vegetation phenology change in Northeast China from 1982 to 2015.

    Science.gov (United States)

    Yu, Lingxue; Liu, Tingxiang; Bu, Kun; Yan, Fengqin; Yang, Jiuchun; Chang, Liping; Zhang, Shuwen

    2017-11-07

    Global warming has contributed to the extension of the growing season in North Hemisphere. In this paper, we investigated the spatial characteristics of the date of the start of the season (SOS), the date of the end of the season (EOS) and the length of the season (LOS) and their change trends from 1982 to 2015 in Northeast China. Our results showed that there was a significant advance of SOS and a significant delay of EOS, especially in the north part of Northeast China. For the average change slope of EOS in the study area, the delay trend was 0.25 d/y, which was more obvious than the advance trend of -0.13 d/y from the SOS. In particular, the LOS of deciduous needleleaf forest (DNF) and grassland increased with a trend of 0.63 d/y and 0.66 d/y from 1982 to 2015, indicating the growth season increased 21.42 and 22.44 days in a 34-year period, respectively. However, few negative signals were detected nearby Hulun Lake, suggesting that the continuous climate warming in the future may bring no longer growing periods for the grass in the semiarid areas as the drought caused by climate warming may limit the vegetation growth.

  6. The global economic long-term potential of modern biomass in a climate-constrained world

    Science.gov (United States)

    Klein, David; Humpenöder, Florian; Bauer, Nico; Dietrich, Jan Philipp; Popp, Alexander; Bodirsky, Benjamin Leon; Bonsch, Markus; Lotze-Campen, Hermann

    2014-07-01

    Low-stabilization scenarios consistent with the 2 °C target project large-scale deployment of purpose-grown lignocellulosic biomass. In case a GHG price regime integrates emissions from energy conversion and from land-use/land-use change, the strong demand for bioenergy and the pricing of terrestrial emissions are likely to coincide. We explore the global potential of purpose-grown lignocellulosic biomass and ask the question how the supply prices of biomass depend on prices for greenhouse gas (GHG) emissions from the land-use sector. Using the spatially explicit global land-use optimization model MAgPIE, we construct bioenergy supply curves for ten world regions and a global aggregate in two scenarios, with and without a GHG tax. We find that the implementation of GHG taxes is crucial for the slope of the supply function and the GHG emissions from the land-use sector. Global supply prices start at 5 GJ-1 and increase almost linearly, doubling at 150 EJ (in 2055 and 2095). The GHG tax increases bioenergy prices by 5 GJ-1 in 2055 and by 10 GJ-1 in 2095, since it effectively stops deforestation and thus excludes large amounts of high-productivity land. Prices additionally increase due to costs for N2O emissions from fertilizer use. The GHG tax decreases global land-use change emissions by one-third. However, the carbon emissions due to bioenergy production increase by more than 50% from conversion of land that is not under emission control. Average yields required to produce 240 EJ in 2095 are roughly 600 GJ ha-1 yr-1 with and without tax.

  7. The global economic long-term potential of modern biomass in a climate-constrained world

    International Nuclear Information System (INIS)

    Klein, David; Humpenöder, Florian; Bauer, Nico; Dietrich, Jan Philipp; Popp, Alexander; Leon Bodirsky, Benjamin; Bonsch, Markus; Lotze-Campen, Hermann

    2014-01-01

    Low-stabilization scenarios consistent with the 2 °C target project large-scale deployment of purpose-grown lignocellulosic biomass. In case a GHG price regime integrates emissions from energy conversion and from land-use/land-use change, the strong demand for bioenergy and the pricing of terrestrial emissions are likely to coincide. We explore the global potential of purpose-grown lignocellulosic biomass and ask the question how the supply prices of biomass depend on prices for greenhouse gas (GHG) emissions from the land-use sector. Using the spatially explicit global land-use optimization model MAgPIE, we construct bioenergy supply curves for ten world regions and a global aggregate in two scenarios, with and without a GHG tax. We find that the implementation of GHG taxes is crucial for the slope of the supply function and the GHG emissions from the land-use sector. Global supply prices start at $5 GJ −1 and increase almost linearly, doubling at 150 EJ (in 2055 and 2095). The GHG tax increases bioenergy prices by $5 GJ −1 in 2055 and by $10 GJ −1 in 2095, since it effectively stops deforestation and thus excludes large amounts of high-productivity land. Prices additionally increase due to costs for N 2 O emissions from fertilizer use. The GHG tax decreases global land-use change emissions by one-third. However, the carbon emissions due to bioenergy production increase by more than 50% from conversion of land that is not under emission control. Average yields required to produce 240 EJ in 2095 are roughly 600 GJ ha −1 yr −1 with and without tax. (letter)

  8. Long-term changes of macular retinal thickness after idiopathic macular hole surgery

    Directory of Open Access Journals (Sweden)

    Yan Yang

    2014-12-01

    .40,291.58±18.97μmin stage A significantly decreased compared to that of the corresponding areas in stage C(276.08±32.39, 278.75±10.19μm(PCONCLUSION: SD-OCT is a convenient tool for the observation of macular regional changes after macular hole surgery. Macular RT had persistent changes after vitrectomy on eyes with macular hole by SD-OCT. ILM peeling may have caused microstructural changes in wide areas of the macular region after PPV surgery. More support and evidence were provided to the further study of the long-term observation for the structural and function of macular after macular hole surgery.

  9. Characterization of long-term geological changes for final disposal of spent fuel in Finland

    International Nuclear Information System (INIS)

    Vuorela, P.; Blomqvist, R.; Aikaes, T.

    1996-01-01

    The bedrock of Finland is very old and major crustal deformation processes ceased long ago. At present continuous slow processes prevail and geological changes taking place today are very difficult to observe. Anticipated future geological changes are dominated by the renewed development of the continental ice sheet in northern Europe. The present climate will deteriorate to a state amenable to glacier formation. Continuous processes such as groundwater flow and interrelated hydrogeochemical phenomena will be influenced by changes in the climate as well as by developing permafrost. The crust itself will be loaded by the weight of the ice sheet, and will will warp down. The final disposal programme has been devised with even more exceptional future changes in mind. The process of site identification in the site selection research programme has been developed to consider the eventuality of the future bedrock movements. Analysis of bedrock geometry and block patterns, together with related fracture zones assists in selecting a repository site where the risks of accumulation of large stresses, and their subsequent release as shear movements, can be minimized. By studying the prevailing conditions and tracing the record of earlier events an understanding of the relevant processes in general is developed. Paleo-hydrogeology is one of the areas which can provide information relating to 'why the conditions at the site today are as they are'. Although it is not possible to predict the future behavior of a site in a detailed manner, it is possible to constrain the scenarios needed in the safety assessment by establishing and documenting real events that have sometimes occurred, and that will most probably be repeated. (authors). 31 refs., 8 figs

  10. The effects of habitat, climate, and Barred Owls on long-term demography of Northern Spotted Owls

    Science.gov (United States)

    Dugger, Catherine; Forsman, Eric D.; Franklin, Alan B.; Davis, Raymond J.; White, Gary C.; Schwarz, Carl J.; Burnham, Kenneth P.; Nichols, James D.; Hines, James E.; Yackulic, Charles B.; Doherty, Paul F.; Bailey, Larissa; Clark, Darren A.; Ackers, Steven H.; Andrews, Lawrence S.; Augustine, Benjamin; Biswell, Brian L.; Blakesley, Jennifer; Carlson, Peter C.; Clement, Matthew J.; Diller, Lowell V.; Glenn, Elizabeth M.; Green, Adam; Gremel, Scott A.; Herter, Dale R.; Higley, J. Mark; Hobson, Jeremy; Horn, Rob B.; Huyvaert, Kathryn P.; McCafferty, Christopher; McDonald, Trent; McDonnell, Kevin; Olson, Gail S.; Reid, Janice A.; Rockweit, Jeremy; Ruiz, Viviana; Saenz, Jessica; Sovern, Stan G.

    2016-01-01

    covariates. In contrast, meta-analysis results suggested that Spotted Owl survival was higher across all study areas when the Pacific Decadal Oscillation (PDO) was in a warming phase and the Southern Oscillation Index (SOI) was negative, with a strongly negative SOI indicative of El Niño events. The best model that included the Barred Owl covariate (BO) was ranked 4th and also included the PDO covariate, but the BO effect was strongly negative. Our results indicated that Northern Spotted Owl populations were declining throughout the range of the subspecies and that annual rates of decline were accelerating in many areas. We observed strong evidence that Barred Owls negatively affected Spotted Owl populations, primarily by decreasing apparent survival and increasing local territory extinction rates. However, the amount of suitable owl habitat, local weather, and regional climatic patterns also were related to survival, occupancy (via colonization rate), recruitment, and, to a lesser extent, fecundity, although there was inconsistency in regard to which covariates were important for particular demographic parameters or across study areas. In the study areas where habitat was an important source of variation for Spotted Owl demographics, vital rates were generally positively associated with a greater amount of suitable owl habitat. However, Barred Owl densities may now be high enough across the range of the Northern Spotted Owl that, despite the continued management and conservation of suitable owl habitat on federal lands, the long-term prognosis for the persistence of Northern Spotted Owls may be in question without additional management intervention. Based on our study, the removal of Barred Owls from the Green Diamond Resources (GDR) study area had rapid, positive effects on Northern Spotted Owl survival and the rate of population change, supporting the hypothesis that, along with habitat conservation and management, Barred Owl removal may be able to slow or reverse

  11. Integrating Social Science into the Long-Term Ecological Research (LTER) Network: Social Dimensions of Ecological Change and Ecological Dimensions of Social Change

    Science.gov (United States)

    Charles L. Redman; J. Morgan Grove; Lauren H. Kuby; Lauren H. Kuby

    2004-01-01

    The integration of the social sciences into long-term ecological research is an urgent priority. To address this need, a group of social, earth, and life scientists associated with the National Science Foundation's (NSF) Long-Term Ecological Research (LTER) Network have articulated a conceptual framework for understanding the human dimensions of ecological change...

  12. Long-term changes in childhood malnutrition are associated with long-term changes in maternal BMI: evidence from Bangladesh, 1996-2011.

    Science.gov (United States)

    Hasan, Md Tanvir; Soares Magalhães, Ricardo J; Williams, Gail M; Mamun, Abdullah A

    2016-10-01

    Nutritional transition (from under- to overnutrition) among women of reproductive age (15-49 y) is becoming increasingly common in many developing countries, including Bangladesh. However, the influence of this transition on the nutritional status of children malnutrition in U5s has changed over time. We analyzed data assembled from 5 Demographic and Health Surveys conducted between 1996 and 2011 in Bangladesh to describe the nutritional status of 28,941 U5s and their mothers. A Poisson regression model was used to examine the associations between maternal BMI and stunting, underweight, and wasting in U5s over time. A nutritional transition among mothers of U5s was observed between 1996 and 2011. The height- or length-for-age and weight-for-age z score distributions of U5s showed consistent improvement; however, there was no indication of a nutritional transition. An interaction was found between maternal BMI categorized as underweight [BMI (kg/m 2 ) malnutrition in children. A nutritional transition among U5s has yet to occur in Bangladesh. However, our results indicate that improvement in maternal BMI in the past 15 y was accompanied by a reduction in malnutrition in U5s. © 2016 American Society for Nutrition.

  13. Towards sustainable adaptation to climate change: The role of ...

    African Journals Online (AJOL)

    Towards sustainable adaptation to climate change: The role of indigenous ... From the short to the long term, climate change and variability threaten human and ... to food insecurity, lack of potable water and poor health, but also the cultural ...

  14. Long-term changes of the phytoplankton community and biomass in the subtropical shallow Patos Lagoon Estuary, Brazil

    Science.gov (United States)

    Haraguchi, Lumi; Carstensen, Jacob; Abreu, Paulo Cesar; Odebrecht, Clarisse

    2015-09-01

    Seasonal and interannual changes (1993-2012) of water temperature and transparency, river discharge, salinity, water quality properties, chlorophyll a (chl-a) and the carbon biomass of the main taxonomical phytoplankton groups were evaluated at a shallow station (∼2 m) in the subtropical Patos Lagoon Estuary (PLE), Brazil. Large variations in salinity (0-35), due to a complex balance between Patos Lagoon outflow and oceanic inflows, affected significantly other water quality variables and phytoplankton dynamics, masking seasonal and interannual variability. Therefore, salinity effect was filtered out by means of a Generalized Additive Model (GAM). River discharge and salinity had a significant negative relation, with river discharge being highest and salinity lowest during July to October. Diatoms comprised the dominant phytoplankton group, contributing substantially to the seasonal cycle of chl-a showing higher values in austral spring/summer (September to April) and lowest in autumn/winter (May to August). PLE is a nutrient-rich estuary and the phytoplankton seasonal cycle was largely driven by light availability, with few exceptions in winter. Most variables exhibited large interannual variability. When varying salinity effect was accounted for, chl-a concentration and diatom biomass showed less irregularity over time, and significant increasing trends emerged for dinoflagellates and cyanobacteria. Long-term changes in phytoplankton and water quality were strongly related to variations in salinity, largely driven by freshwater discharge influenced by climatic variability, most pronounced for ENSO events. However, the significant increasing trend of the N:P ratio indicates that important environmental changes related to anthropogenic effects are undergoing, in addition to the hydrology in the PLE.

  15. Effects of climate variability and climate change on crop production in southern Mali

    NARCIS (Netherlands)

    Traore, B.; Corbeels, M.; Wijk, van M.T.; Rufino, M.C.; Giller, K.E.

    2013-01-01

    In West Africa predictions of future changes in climate and especially rainfall are highly uncertain, and up to now no long-term analyses are available of the effects of climate on crop production. This study analyses long-term trends in climate variability at N'Tarla and Sikasso in southern Mali

  16. Long-term changes in cognitive bias and coping response as a result of chronic unpredictable stress during adolescence

    Directory of Open Access Journals (Sweden)

    Lauren eChaby

    2013-07-01

    Full Text Available Animals that experience adverse events in early life often have life-long changes to their physiology and behavior. Long-term effects of stress during early life have been studied extensively, but less attention has been given to the consequences of negative experiences solely during the adolescent phase. Adolescence is a particularly sensitive period of life when regulation of the glucocorticoid stress hormone response matures and specific regions in the brain undergo considerable change. Aversive experiences during this time might, therefore, be expected to generate long-term consequences for the adult phenotype. Here we investigated the long-term effects of exposure to chronic unpredictable stress during adolescence on adult decision making, coping response, cognitive bias, and exploratory behavior in rats. Rats exposed to chronic unpredictable stress (e.g. isolation, crowding, cage tilt were compared to control animals that were maintained in standard, predictable conditions throughout development. Unpredictable stress during adolescence resulted in a suite of long-term behavioral and cognitive changes including a negative cognitive bias (F1,12 = 5.000, P < 0.05, altered coping response (T1,14 = 2.216, P = 0.04, and accelerated decision making (T1,14 = 3.245, P = 0.01. Exposure to chronic stress during adolescence also caused a short-term increase in boldness behaviors; in a novel object test 15 days after the last stressor, animals exposed to chronic unpredictable stress had decreased latencies to leave a familiar shelter and approach a novel object (T1,14 = 2.240, P = 0.04; T1,14 = 2.419, P = 0.03, respectively. The results showed that stress during adolescence has long-term impacts on behavior and cognition that affect the interpretation of ambiguous stimuli, behavioral response to adverse events, and how animals make decisions. Stress during adolescence also induced short-term changes in the way animals moved around a novel environment.

  17. Functional adjustments of xylem anatomy to climatic variability: insights from long-term Ilex aquifolium tree-ring series.

    Science.gov (United States)

    Rita, Angelo; Cherubini, Paolo; Leonardi, Stefano; Todaro, Luigi; Borghetti, Marco

    2015-08-01

    The present study assessed the effects of climatic conditions on radial growth and functional anatomical traits, including ring width, vessel size, vessel frequency and derived variables, i.e., potential hydraulic conductivity and xylem vulnerability to cavitation in Ilex aquifolium L. trees using long-term tree-ring time series obtained at two climatically contrasting sites, one mesic site in Switzerland (CH) and one drought-prone site in Italy (ITA). Relationships were explored by examining different xylem traits, and point pattern analysis was applied to investigate vessel clustering. We also used generalized additive models and bootstrap correlation functions to describe temperature and precipitation effects. Results indicated modified radial growth and xylem anatomy in trees over the last century; in particular, vessel frequency increased markedly at both sites in recent years, and all xylem traits examined, with the exception of xylem cavitation vulnerability, were higher at the CH mesic compared with the ITA drought site. A significant vessel clustering was observed at the ITA site, which could contribute to an enhanced tolerance to drought-induced embolism. Flat and negative relationships between vessel size and ring width were observed, suggesting carbon was not allocated to radial growth under conditions which favored stem water conduction. Finally, in most cases results indicated that climatic conditions influenced functional anatomical traits more substantially than tree radial growth, suggesting a crucial role of functional xylem anatomy in plant acclimation to future climatic conditions. © The Author 2015. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  18. Detecting long-term changes to vegetation in northern Canada using the Landsat satellite image archive

    International Nuclear Information System (INIS)

    Fraser, R H; Olthof, I; Carrière, M; Deschamps, A; Pouliot, D

    2011-01-01

    Analysis of coarse resolution (∼1 km) satellite imagery has provided evidence of vegetation changes in arctic regions since the mid-1980s that may be attributable to climate warming. Here we investigate finer-scale changes to northern vegetation over the same period using stacks of 30 m resolution Landsat TM and ETM + satellite images. Linear trends in the normalized difference vegetation index (NDVI) and tasseled cap indices are derived for four widely spaced national parks in northern Canada. The trends are related to predicted changes in fractional shrub and other vegetation covers using regression tree classifiers trained with plot measurements and high resolution imagery. We find a consistent pattern of greening (6.1–25.5% of areas increasing) and predicted increases in vascular vegetation in all four parks that is associated with positive temperature trends. Coarse resolution (3 km) NDVI trends were not detected in two of the parks that had less intense greening. A range of independent studies and observations corroborate many of the major changes observed.

  19. Climate Change Mitigation A Balanced Approach to Climate Change

    CERN Document Server

    2012-01-01

    This book provides a fresh and innovative perspective on climate change policy. By emphasizing the multiple facets of climate policy, from mitigation to adaptation, from technological innovation and diffusion to governance issues, it contains a comprehensive overview of the economic and policy dimensions of the climate problem. The keyword of the book is balance. The book clarifies that climate change cannot be controlled by sacrificing economic growth and many other urgent global issues. At the same time, action to control climate change cannot be delayed, even though gradually implemented. Therefore, on the one hand climate policy becomes pervasive and affects all dimensions of international policy. On the other hand, climate policy cannot be too ambitious: a balanced approach between mitigation and adaptation, between economic growth and resource management, between short term development efforts and long term innovation investments, should be adopted. I recommend its reading. Carlo Carraro, President, Ca�...

  20. Restoration treatments in urban park forests drive long-term changes in vegetation trajectories.

    Science.gov (United States)

    Johnson, Lea R; Handel, Steven N

    2016-04-01

    Municipalities are turning to ecological restoration of urban forests as a measure to improve air quality, ameliorate urban heat island effects, improve storm water infiltration, and provide other social and ecological benefits. However, community dynamics following urban forest restoration treatments are poorly documented. This study examines the long-term effects of ecological restoration undertaken in New York City, New York, USA, to restore native forest in urban park natural areas invaded by woody non-native plants that are regional problems. In 2009 and 2010, we sampled vegetation in 30 invaded sites in three large public parks that were restored 1988-1993, and 30 sites in three large parks that were similarly invaded but had not been restored. Data from these matched plots reveal that the restoration treatment achieved its central goals. After 15-20 years, invasive species removal followed by native tree planting resulted in persistent structural and compositional shifts, significantly lower invasive species abundance, a more complex forest structure, and greater native tree recruitment. Together, these findings indicate that successional trajectories of vegetation dynamics have diverged between restored forests and invaded forests that were not restored. In addition, the data suggest that future composition of these urban forest patches will be novel assemblages. Restored and untreated sites shared a suite of shade-intolerant, quickly-growing tree species that colonize disturbed sites, indicating that restoration treatments created sites hospitable for germination and growth of species adapted to high light conditions and disturbed soils. These findings yield an urban perspective on the use of succession theory in ecological restoration. Models of ecological restoration developed in more pristine environments must be modified for use in cities. By anticipating both urban disturbances and ecological succession, management of urban forest patches can be

  1. Analysis of rainfall and temperature time series to detect long-term climatic trends and variability over semi-arid Botswana

    Science.gov (United States)

    Byakatonda, Jimmy; Parida, B. P.; Kenabatho, Piet K.; Moalafhi, D. B.

    2018-03-01

    Arid and semi-arid environments have been identified with locations prone to impacts of climate variability and change. Investigating long-term trends is one way of tracing climate change impacts. This study investigates variability through annual and seasonal meteorological time series. Possible inhomogeneities and years of intervention are analysed using four absolute homogeneity tests. Trends in the climatic variables were determined using Mann-Kendall and Sen's Slope estimator statistics. Association of El Niño Southern Oscillation (ENSO) with local climate is also investigated through multivariate analysis. Results from the study show that rainfall time series are fully homogeneous with 78.6 and 50% of the stations for maximum and minimum temperature, respectively, showing homogeneity. Trends also indicate a general decrease of 5.8, 7.4 and 18.1% in annual, summer and winter rainfall, respectively. Warming trends are observed in annual and winter temperature at 0.3 and 1.5% for maximum temperature and 1.7 and 6.5% for minimum temperature, respectively. Rainfall reported a positive correlation with Southern Oscillation Index (SOI) and at the same time negative association with Sea Surface Temperatures (SSTs). Strong relationships between SSTs and maximum temperature are observed during the El Niño and La Niña years. These study findings could facilitate planning and management of agricultural and water resources in Botswana.

  2. Is Recovery of Large-Bodied Zooplankton after Nutrient Loading Reduction Hampered by Climate Warming? A Long-Term Study of Shallow Hypertrophic Lake Søbygaard, Denmark

    Directory of Open Access Journals (Sweden)

    María Florencia Gutierrez

    2016-08-01

    Full Text Available Nutrient fluctuations and climate warming can synergistically affect trophic dynamics in lakes, resulting in enhanced symptoms of eutrophication, thereby potentially counteracting restoration measures. We performed a long-term study (23 years of zooplankton in Danish Lake Søbygaard, which is in recovery after nutrient loading reduction, but now faces the effects of climate warming. We hypothesized that the recovery of large-bodied zooplankton after nutrient loading reduction would be hampered by climate warming through indirect effects on fish size structure. We found a shift in macrozooplankton from initial dominance of Daphnia spp. towards Bosmina spp. as well as a decline in the body size of copepods and an increase in the abundance of nauplii. These changes coincided with the increase in small sized fish as a result of rising water temperature. Despite a reduction in body size, the total biomass of cladocerans increased coinciding with a diminished fish catch per unit effort (CPUE, and likely then an overall reduction in the predation on zooplankton. A cascading effect to phytoplankton was evidenced by enhanced zooplankton:phytoplankton and cladoceran:phytoplankton ratios and a decrease in Chl-a:TP and Chl-a:TN ratios. Our results indicate that climate warming, through changes in the size structure of fish community, has major effects on zooplankton size structure. In Lake Søbygaard, the decline in zooplankton size did not prevent, but modulated, the positive cascading effect on phytoplankton through an expected diminished fish CPUE related to nutrient loading reduction.

  3. Long-term changes in cognitive bias and coping response as a result of chronic unpredictable stress during adolescence.

    Science.gov (United States)

    Chaby, Lauren E; Cavigelli, Sonia A; White, Amanda; Wang, Kayllie; Braithwaite, Victoria A

    2013-01-01

    Animals that experience adverse events in early life often have life-long changes to their physiology and behavior. Long-term effects of stress during early life have been studied extensively, but less attention has been given to the consequences of negative experiences solely during the adolescent phase. Adolescence is a particularly sensitive period of life when regulation of the glucocorticoid "stress" hormone response matures and specific regions in the brain undergo considerable change. Aversive experiences during this time might, therefore, be expected to generate long-term consequences for the adult phenotype. Here we investigated the long-term effects of exposure to chronic unpredictable stress during adolescence on adult decision-making, coping response, cognitive bias, and exploratory behavior in rats. Rats exposed to chronic unpredictable stress (e.g., isolation, crowding, cage tilt) were compared to control animals that were maintained in standard, predictable conditions throughout development. Unpredictable stress during adolescence resulted in a suite of long-term behavioral and cognitive changes including a negative cognitive bias [F (1, 12) = 5.000, P chronic stress during adolescence also caused a short-term increase in boldness behaviors; in a novel object test 15 days after the last stressor, animals exposed to chronic unpredictable stress had decreased latencies to leave a familiar shelter and approach a novel object [T (1, 14) = 2.240, P = 0.04; T (1, 14) = 2.419, P = 0.03, respectively]. The results showed that stress during adolescence has long-term impacts on behavior and cognition that affect the interpretation of ambiguous stimuli, behavioral response to adverse events, and how animals make decisions.

  4. Length change of the alloys Waspaloy and Inconel 718 after long-term annealing

    International Nuclear Information System (INIS)

    Kinzel, Svenja

    2016-01-01

    Within the scope of this work the contraction behavior of Ni-based superalloy Waspaloy could in detail be referred to a combination of different microstructural changes and the results could partially be transferred to Ni-Fe-based alloy Inconel 718. Isothermal annealing of sample rods at temperatures between 450 C and 750 C induces an average relative length contraction of about -2.10"-"4. It is apparent that contraction is more pronounced for lower temperatures (-3.10"-"4 at 550 C) than for higher ones (-1.10"-"4 at 750 C). Within the first 300 hours of annealing the contraction reaches about 70-75% of the value measured after 10,000 hours. This means the major part of the effect takes place at the beginning of long term annealing but even after 10,000 hours no saturation occurs. On the basis of lattice parameter measurements it could be found that within the first 300 hours a significant lattice parameter decrease of matrix and γ"' phase emerged. Longer annealing time does not cause further lattice contraction. This sample behavior can be explained by temperature dependence of phase fractions and phase compositions. Thermodynamic calculations as well as stereological analysis of micrographs show a decrease of stable γ"'-phase content with increasing temperature. In parallel, TEM-EDS measurements and calculated phase fractions show concentration fluctuations due to the different precipitate fraction, which cause contraction of the lattice parameter. Furthermore, within the first 100 hours at temperatures up to 650 C the formation or Ni-Cr rich domains could be observed. As these domains exhibit a smaller lattice parameter than the matrix they contribute to the more pronounced contraction at lower temperatures. While XRD measurements point to the formation of Ni_3Cr, TEM-EDS measurements reveal a composition of (Ni,Co)_2Cr. Stress relief heat treatment at higher temperatures (815 C) after annealing shows that the effect of contraction is reversible. It causes an

  5. Estuaries of the Greater Everglades Ecosystem: Laboratories of Long-term Change

    Science.gov (United States)

    Wingard, G.L.; Hudley, J.W.; Marshall, F.E.

    2010-01-01

    Restoring the greater Everglades ecosystem of south Florida is arguably the largest ecosystem restoration effort to date. A critical goal is to return more natural patterns of flow through south Florida wetlands and into the estuaries, but development of realistic targets requires acknowledgement that ecosystems are constantly evolving and changing in response to a variety of natural and human-driven stressors. Examination of ecosystems over long periods of time requires analysis of sedimentary records, such as those deposited in the wetlands and estuaries of south Florida. As sediment accumulates, it preserves information about the animals and plants that lived in the environment and the physical, chemical, and climatic conditions present. One of the methods used to interpret this information is paleoecology-the study of the ecology of previously living organisms. Paleoecologic investigations of south Florida estuaries provide quantitative data on historical variability of salinity and trends that may be applied to statistical models to estimate historical freshwater flow. These data provide a unique context to estimate future ecosystem response to changes related to restoration activities and predicted changes in sea level and temperature, thus increasing the likelihood of successful and sustainable ecosystem restoration.

  6. Geosphere Stability for long-term isolation of radioactive waste. Case study for hydrological change with earthquakes and faulting

    International Nuclear Information System (INIS)

    Niwa, Masakazu

    2016-01-01

    Appropriate estimation and safety assessment for long-term changes in geological environment are essential to an improvement of reliability for geological disposal. Specifically, study on faults is important for understanding regional groundwater flow as well as an assessment as a trigger of future earthquakes. Here, possibility of changes in permeability of faulted materials induced by earthquakes was examined based on monitoring data of groundwater pressure before and after the 2011 off the Pacific coast of Tohoku Earthquake. (author)

  7. Long-term ecological data for conservation: Range change in the black-billed capercaillie (Tetrao urogalloides) in northeast China (1970s-2070s).

    Science.gov (United States)

    Yang, Li; Zhang, Chao; Chen, Minhao; Li, Jingxin; Yang, Lei; Huo, Zhaomin; Ahmad, Shahid; Luan, Xiaofeng

    2018-04-01

    Long-term ecological data can be an effective tool to help ecologists integrate future projections with historical contexts and provide unique insights into the long-term dynamics of endangered species. However, hampered by data limitations, including incomplete and spatially biased data, relatively few studies have used multidecadal datasets or have examined changes in biogeography from a historical perspective. The black-billed capercaillie ( Tetrao urogalloides ) is a large capercaillie (classified as Least Concern [LC] on the IUCN red list) that has undergone a dramatic decline in population during the late 20th century and is considered endangered. Its conservation status is pessimistic, and the species requires immediate protection. Therefore, we supplemented a historical dataset to identify changes in this bird's range and population in northeast China over the long term. The study area spanned Heilongjiang Province, Jilin Province, and the northeast corner of Inner Mongolia in northeast China. We integrated an ecological niche model (BIOMOD2) with long-term ecological data on this species to estimate the magnitude of change in distribution over time. Our results revealed a 35.25% reduction in the current distribution of this species compared to their potential distribution in the 1970s. This decline is expected to continue under climate change. For example, the future range loss was estimated to be 38.79 ± 0.22% (8.64-90.19%), and the actual state could be worse, because the baseline range of the model was greater than the real range in the 2000s, showing a 12.39% overestimation. To overcome this poor outlook, a conservation strategy should be established in sensitive areas, including the southwestern Greater Khingan Mountains and northern Lesser Khingan Mountains. Actions that should be considered include field investigations, establishing a monitor network, designing ecological corridors, and cooperating with local inhabitants, governments, and

  8. Long-Term Field Data and Climate-Habitat Models Show That Orangutan Persistence Depends on Effective Forest Management and Greenhouse Gas Mitigation

    Science.gov (United States)

    Gregory, Stephen D.; Brook, Barry W.; Goossens, Benoît; Ancrenaz, Marc; Alfred, Raymond; Ambu, Laurentius N.; Fordham, Damien A.

    2012-01-01

    Background Southeast Asian deforestation rates are among the world’s highest and threaten to drive many forest-dependent species to extinction. Climate change is expected to interact with deforestation to amplify this risk. Here we examine whether regional incentives for sustainable forest management will be effective in improving threatened mammal conservation, in isolation and when combined with global climate change mitigation. Methodology/Principal Findings Using a long time-series of orangutan nest counts for Sabah (2000–10), Malaysian Borneo, we evaluated the effect of sustainable forest management and climate change scenarios, and their interaction, on orangutan spatial abundance patterns. By linking dynamic land-cover and downscaled global climate model projections, we determine the relative influence of these factors on orangutan spatial abundance and use the resulting statistical models to identify habitat crucial for their long-term conservation. We show that land-cover change the degradation of primary forest had the greatest influence on orangutan population size. Anticipated climate change was predicted to cause reductions in abundance in currently occupied populations due to decreased habitat suitability, but also to promote population growth in western Sabah by increasing the suitability of presently unoccupied regions. Conclusions/Significance We find strong quantitative support for the Sabah government’s proposal to implement sustainable forest management in all its forest reserves during the current decade; failure to do so could result in a 40 to 80 per cent regional decline in orangutan abundance by 2100. The Sabah orangutan is just one (albeit iconic) example of a forest-dependent species that stands to benefit from sustainable forest management, which promotes conservation of existing forests. PMID:22970145

  9. Long-term changes of the glacial seismicity: case study from Spitsbergen

    Science.gov (United States)

    Gajek, Wojciech; Trojanowski, Jacek; Malinowski, Michał

    2016-04-01

    Changes in global temperature balance have proved to have a major impact on the cryosphere, and therefore withdrawing glaciers are the symbol of the warming climate. Our study focuses on year-to-year changes in glacier-generated seismicity. We have processed 7-year long continuous seismological data recorded by the HSP broadband station located in the proximity of Hansbreen glacier (Hornsund, southern Spitsbergen), obtaining seismic activity distribution between 2008 and 2014. We developed a new fuzzy logic algorithm to distinguish between glacier- and non-glacier-origin events. The algorithm takes into account the frequency of seismic signal and the energy flow in certain time interval. Our research has revealed that the number of detected glacier-origin events over last two years has doubled. Annual events distribution correlates well with temperature and precipitation curves, illustrating characteristic yearlong behaviour of glacier seismic activity. To further support our observations, we have analysed 5-year long distribution of glacier-origin tremors detected in the vicinity of the Kronebreen glacier using KBS broadband station located in Ny-Ålesund (western Spitsbergen). We observe a steady increase in the number of detected events. detected each year, however not as significant as for Hornsund dataset.

  10. Predicting the long-term durability of hemp-lime renders in inland and coastal areas using Mediterranean, Tropical and Semi-arid climatic simulations.

    Science.gov (United States)

    Arizzi, Anna; Viles, Heather; Martín-Sanchez, Inés; Cultrone, Giuseppe

    2016-01-15

    Hemp-based composites are eco-friendly building materials as they improve energy efficiency in buildings and entail low waste production and pollutant emissions during their manufacturing process. Nevertheless, the organic nature of hemp enhances the bio-receptivity of the material, with likely negative consequences for its long-term performance in the building. The main purpose of this study was to study the response at macro- and micro-scale of hemp-lime renders subjected to weathering simulations in an environmental cabinet (one year was condensed in twelve days), so as to predict their long-term durability in coastal and inland areas with Mediterranean, Tropical and Semi-arid climates, also in relation with the lime type used. The simulated climatic conditions caused almost unnoticeable mass, volume and colour changes in hemp-lime renders. No efflorescence or physical breakdown was detected in samples subjected to NaCl, because the salt mainly precipitates on the surface of samples and is washed away by the rain. Although there was no visible microbial colonisation, alkaliphilic fungi (mainly Penicillium and Aspergillus) and bacteria (mainly Bacillus and Micrococcus) were isolated in all samples. Microbial growth and diversification were higher under Tropical climate, due to heavier rainfall. The influence of the bacterial activity on the hardening of samples has also been discussed here and related with the formation and stabilisation of vaterite in hemp-lime mixes. This study has demonstrated that hemp-lime renders show good durability towards a wide range of environmental conditions and factors. However, it might be useful to take some specific preventive and maintenance measures to reduce the bio-receptivity of this material, thus ensuring a longer durability on site. Copyright © 2015 Elsevier B.V. All rights reserved.

  11. Barriers and Facilitators to Implementing a Change Initiative in Long-Term Care Using the INTERACT® Quality Improvement Program.

    Science.gov (United States)

    Tappen, Ruth M; Wolf, David G; Rahemi, Zahra; Engstrom, Gabriella; Rojido, Carolina; Shutes, Jill M; Ouslander, Joseph G

    Implementation of major organizational change initiatives presents a challenge for long-term care leadership. Implementation of the INTERACT® (Interventions to Reduce Acute Care Transfers) quality improvement program, designed to improve the management of acute changes in condition and reduce unnecessary emergency department visits and hospitalizations of nursing home residents, serves as an example to illustrate the facilitators and barriers to major change in long-term care. As part of a larger study of the impact of INTERACT® on rates of emergency department visits and hospitalizations, staff of 71 nursing homes were called monthly to follow-up on their progress and discuss successful facilitating strategies and any challenges and barriers they encountered during the yearlong implementation period. Themes related to barriers and facilitators were identified. Six major barriers to implementation were identified: the magnitude and complexity of the change (35%), instability of facility leadership (27%), competing demands (40%), stakeholder resistance (49%), scarce resources (86%), and technical problems (31%). Six facilitating strategies were also reported: organization-wide involvement (68%), leadership support (41%), use of administrative authority (14%), adequate training (66%), persistence and oversight on the part of the champion (73%), and unfolding positive results (14%). Successful introduction of a complex change such as the INTERACT® quality improvement program in a long-term care facility requires attention to the facilitators and barriers identified in this report from those at the frontline.

  12. Delineating and identifying long-term changes in the whooping crane (Grus americana) migration corridor

    Science.gov (United States)

    Pearse, Aaron T.; Rabbe, Matt; Juliusson, Lara M.; Bidwell, Mark T.; Craig-Moore, Lea; Brandt, David; Harrell, Wade C.

    2018-01-01

    Defining and identifying changes to seasonal ranges of migratory species is required for effective conservation. Historic sightings of migrating whooping cranes (Grus americana) have served as sole source of information to define a migration corridor in the Great Plains of North America (i.e., Canadian Prairies and United States Great Plains) for this endangered species. We updated this effort using past opportunistic sightings from 1942–2016 (n = 5,055) and more recent (2010–2016) location data from 58 telemetered birds (n = 4,423) to delineate migration corridors that included 50%, 75%, and 95% core areas. All migration corridors were well defined and relatively compact, with the 95% core corridor averaging 294 km wide, although it varied approximately ±40% in width from 170 km in central Texas to 407 km at the international border of the United States and Canada. Based on historic sightings and telemetry locations, we detected easterly movements in locations over time, primarily due to locations west of the median shifting east. This shift occurred from northern Oklahoma to central Saskatchewan at an average rate of 1.2 km/year (0.3–2.8 km/year). Associated with this directional shift was a decrease in distance of locations from the median in the same region averaging -0.7 km/year (-0.3–-1.3 km/year), suggesting a modest narrowing of the migration corridor. Changes in the corridor over the past 8 decades suggest that agencies and organizations interested in recovery of this species may need to modify where conservation and recovery actions occur. Whooping cranes showed apparent plasticity in their migratory behavior, which likely has been necessary for persistence of a wetland-dependent species migrating through the drought-prone Great Plains. Behavioral flexibility will be useful for whooping cranes to continue recovery in a future of uncertain climate and land use changes throughout their annual range.

  13. Long-term and seasonal Caspian Sea level change from satellite gravity and altimeter measurements

    Science.gov (United States)

    Chen, J. L.; Wilson, C. R.; Tapley, B. D.; Save, H.; Cretaux, Jean-Francois

    2017-03-01

    We examine recent Caspian Sea level change by using both satellite radar altimetry and satellite gravity data. The altimetry record for 2002-2015 shows a declining level at a rate that is approximately 20 times greater than the rate of global sea level rise. Seasonal fluctuations are also much larger than in the world oceans. With a clearly defined geographic region and dominant signal magnitude, variations in the sea level and associated mass changes provide an excellent way to compare various approaches for processing satellite gravity data. An altimeter time series derived from several successive satellite missions is compared with mass measurements inferred from Gravity Recovery and Climate Experiment (GRACE) data in the form of both spherical harmonic (SH) and mass concentration (mascon) solutions. After correcting for spatial leakage in GRACE SH estimates by constrained forward modeling and accounting for steric and terrestrial water processes, GRACE and altimeter observations are in complete agreement at seasonal and longer time scales, including linear trends. This demonstrates that removal of spatial leakage error in GRACE SH estimates is both possible and critical to improving their accuracy and spatial resolution. Excellent agreement between GRACE and altimeter estimates also provides confirmation of steric Caspian Sea level change estimates. GRACE mascon estimates (both the Jet Propulsion Laboratory (JPL) coastline resolution improvement version 2 solution and the Center for Space Research (CSR) regularized) are also affected by leakage error. After leakage corrections, both JPL and CSR mascon solutions also agree well with altimeter observations. However, accurate quantification of leakage bias in GRACE mascon solutions is a more challenging problem.

  14. Long-term structural retinal changes in patients with optic neuritis related to multiple sclerosis

    DEFF Research Database (Denmark)

    Andersen, Maria Rene; Roar, Malte; Sejbaek, Tobias

    2017-01-01

    fiber layer (RNFL) thickness (56 vs 67 μm, P=0.01). In an age- and sex-adjusted logistic regression model, lower inferior and temporal RNFL were associated with a higher risk of ON (odds ratio [OR] 1.56 [95% confidence interval {CI} 1.01-2.41] and OR 1.74 [95% CI 1.10-2.77] per 10 μm decrement in RNFL......PURPOSE: To evaluate the long-term structural and functional outcome in patients with multiple sclerosis (MS) with and without a history of optic neuritis (ON). METHODS: This was a cross-sectional study of 82 patients diagnosed with MS between 2000 and 2006 from a tertiary hospital center...

  15. Long-term structural retinal changes in patients with optic neuritis related to multiple sclerosis

    Science.gov (United States)

    Andersen, Maria Rene; Roar, Malte; Sejbaek, Tobias; Illes, Zsolt; Grauslund, Jakob

    2017-01-01

    Purpose To evaluate the long-term structural and functional outcome in patients with multiple sclerosis (MS) with and without a history of optic neuritis (ON). Methods This was a cross-sectional study of 82 patients diagnosed with MS between 2000 and 2006 from a tertiary hospital center in Denmark. Patients gave a self-reported history of ON, and functional (visual acuity and color vision) and structural (spectra domain optical coherence tomography) markers of vision were tested. Results Median age and MS duration at the time of the clinical examination were 49.9 years (range 30.7–72.6 years) and 13 years (range 9–15 years), respectively. ON was not associated with impairment of visual acuity or color vision. Twenty-three patients had a history of ON in at least one eye. Compared to non-affected patients, these had a lower inferior (109 vs 113 μm, P=0.04) and temporal retinal nerve fiber layer (RNFL) thickness (56 vs 67 μm, P=0.01). In an age- and sex-adjusted logistic regression model, lower inferior and temporal RNFL were associated with a higher risk of ON (odds ratio [OR] 1.56 [95% confidence interval {CI} 1.01–2.41] and OR 1.74 [95% CI 1.10–2.77] per 10 μm decrement in RNFL thickness, respectively). Twenty patients had a history of ON in one eye. Compared to the non-affected eye, this eye had a lower RNFL (109 vs 115 μm, P=0.04) and a higher central retinal thickness/mean RNFL ratio (2.7 vs 2.4, P=0.04). Conclusion Although patients with long-term MS and a previous history of ON did not have any functional loss of vision, structural neurodegeneration could be demonstrated in the affected eye. PMID:28860702

  16. Long-term structural retinal changes in patients with optic neuritis related to multiple sclerosis.

    Science.gov (United States)

    Andersen, Maria Rene; Roar, Malte; Sejbaek, Tobias; Illes, Zsolt; Grauslund, Jakob

    2017-01-01

    To evaluate the long-term structural and functional outcome in patients with multiple sclerosis (MS) with and without a history of optic neuritis (ON). This was a cross-sectional study of 82 patients diagnosed with MS between 2000 and 2006 from a tertiary hospital center in Denmark. Patients gave a self-reported history of ON, and functional (visual acuity and color vision) and structural (spectra domain optical coherence tomography) markers of vision were tested. Median age and MS duration at the time of the clinical examination were 49.9 years (range 30.7-72.6 years) and 13 years (range 9-15 years), respectively. ON was not associated with impai