WorldWideScience

Sample records for climate variability impacts

  1. Climate Impact of Solar Variability

    Science.gov (United States)

    Schatten, Kenneth H. (Editor); Arking, Albert (Editor)

    1990-01-01

    The conference on The Climate Impact of Solar Variability, was held at Goddard Space Flight Center from April 24 to 27, 1990. In recent years they developed a renewed interest in the potential effects of increasing greenhouse gases on climate. Carbon dioxide, methane, nitrous oxide, and the chlorofluorocarbons have been increasing at rates that could significantly change climate. There is considerable uncertainty over the magnitude of this anthropogenic change. The climate system is very complex, with feedback processes that are not fully understood. Moreover, there are two sources of natural climate variability (volcanic aerosols and solar variability) added to the anthropogenic changes which may confuse our interpretation of the observed temperature record. Thus, if we could understand the climatic impact of the natural variability, it would aid our interpretation and understanding of man-made climate changes.

  2. Impacts of Climate Change and Climate Variability on Hydrological Regimes

    Science.gov (United States)

    van Dam, Jan C.

    2003-10-01

    Water is going to be one of the key, if not the most critical, environmental issues in the twenty-first century because of the escalation in socio-economic pressures on the environment in general. Any future climate change or climate variability will only accentuate such pressures. This volume initially follows the perspective of the Intergovernmental Panel on Climate Change (IPCC) to infer possible changes in hydrological regimes and water quality based on the outputs from various scenarios of General Circulation Models (GCMs). In subsequent chapters, the possible effects of climate change on the hydrology of each of the continents is examined. The book concludes with an overview of hydrological models for use in the evaluation of the impacts of climate change. It will provide a valuable guide for environmental planners and policy-makers, and will also be of use to all students and researchers interested in the possible effects of climate change.

  3. Impact of climate variability on tropospheric ozone

    International Nuclear Information System (INIS)

    A simulation with the climate-chemistry model (CCM) E39/C is presented, which covers both the troposphere and stratosphere dynamics and chemistry during the period 1960 to 1999. Although the CCM, by its nature, is not exactly representing observed day-by-day meteorology, there is an overall model's tendency to correctly reproduce the variability pattern due to an inclusion of realistic external forcings, like observed sea surface temperatures (e.g. El Nino), major volcanic eruption, solar cycle, concentrations of greenhouse gases, and Quasi-Biennial Oscillation. Additionally, climate-chemistry interactions are included, like the impact of ozone, methane, and other species on radiation and dynamics, and the impact of dynamics on emissions (lightning). However, a number of important feedbacks are not yet included (e.g. feedbacks related to biogenic emissions and emissions due to biomass burning). The results show a good representation of the evolution of the stratospheric ozone layer, including the ozone hole, which plays an important role for the simulation of natural variability of tropospheric ozone. Anthropogenic NOx emissions are included with a step-wise linear trend for each sector, but no interannual variability is included. The application of a number of diagnostics (e.g. marked ozone tracers) allows the separation of the impact of various processes/emissions on tropospheric ozone and shows that the simulated Northern Hemisphere tropospheric ozone budget is not only dominated by nitrogen oxide emissions and other ozone pre-cursors, but also by changes of the stratospheric ozone budget and its flux into the troposphere, which tends to reduce the simulated positive trend in tropospheric ozone due to emissions from industry and traffic during the late 80s and early 90s. For tropical regions the variability in ozone is dominated by variability in lightning (related to ENSO) and stratosphere-troposphere exchange (related to Northern Hemisphere Stratospheric

  4. Impact of climate variability on tropospheric ozone

    International Nuclear Information System (INIS)

    A simulation with the climate-chemistry model (CCM) E39/C is presented, which covers both the troposphere and stratosphere dynamics and chemistry during the period 1960 to 1999. Although the CCM, by its nature, is not exactly representing observed day-by-day meteorology, there is an overall model's tendency to correctly reproduce the variability pattern due to an inclusion of realistic external forcings, like observed sea surface temperatures (e.g. El Nino), major volcanic eruption, solar cycle, concentrations of greenhouse gases, and Quasi-Biennial Oscillation. Additionally, climate-chemistry interactions are included, like the impact of ozone, methane, and other species on radiation and dynamics, and the impact of dynamics on emissions (lightning). However, a number of important feedbacks are not yet included (e.g. feedbacks related to biogenic emissions and emissions due to biomass burning). The results show a good representation of the evolution of the stratospheric ozone layer, including the ozone hole, which plays an important role for the simulation of natural variability of tropospheric ozone. Anthropogenic NO x emissions are included with a step-wise linear trend for each sector, but no interannual variability is included. The application of a number of diagnostics (e.g. marked ozone tracers) allows the separation of the impact of various processes/emissions on tropospheric ozone and shows that the simulated Northern Hemisphere tropospheric ozone budget is not only dominated by nitrogen oxide emissions and other ozone pre-cursors, but also by changes of the stratospheric ozone budget and its flux into the troposphere, which tends to reduce the simulated positive trend in tropospheric ozone due to emissions from industry and traffic during the late 80s and early 90s. For tropical regions the variability in ozone is dominated by variability in lightning (related to ENSO) and stratosphere-troposphere exchange (related to Northern Hemisphere Stratospheric

  5. Impact of climate variability on vector-borne disease transmission

    Science.gov (United States)

    We will discuss the impact of climate variability on vector borne diseases and demonstrate that global climate teleconnections can be used to anticipate and forecast, in the case of Rift Valley fever, epidemics and epizootics. In this context we will examine significant worldwide weather anomalies t...

  6. Impact of Holocene climate variability on Arctic vegetation

    Science.gov (United States)

    Gajewski, K.

    2015-10-01

    This paper summarizes current knowledge about the postglacial history of the vegetation of the Canadian Arctic Archipelago (CAA) and Greenland. Available pollen data were used to understand the initial migration of taxa across the Arctic, how the plant biodiversity responded to Holocene climate variability, and how past climate variability affected primary production of the vegetation. Current evidence suggests that most of the flora arrived in the area during the Holocene from Europe or refugia south or west of the region immediately after local deglaciation, indicating rapid dispersal of propagules to the region from distant sources. There is some evidence of shrub species arriving later in Greenland, but it is not clear if this is dispersal limited or a response to past climates. Subsequent climate variability had little effect on biodiversity across the CAA, with some evidence of local extinctions in areas of Greenland in the late Holocene. The most significant impact of climate changes is on vegetation density and/or plant production.

  7. A hybrid approach to incorporating climate change and variability into climate scenario for impact assessments

    OpenAIRE

    Gebretsadik, Yohannes; Strzepek, Kenneth; Schlosser, C. Adam

    2014-01-01

    Traditional 'delta-change' approach of scenario generation for climate change impact assessment to water resources strongly depends on the selected base-case observed historical climate conditions that the climate shocks are to be super-imposed. This method disregards the combined effect of climate change and the inherent hydro-climatological variability in the system. Here we demonstrated a hybrid uncertainty approach in which uncertainties in historical climate variability are combined with...

  8. POTENTIAL IMPACTS OF CLIMATIC VARIABILITY ON INDIAN HIMALAYAN REGION

    Directory of Open Access Journals (Sweden)

    Kavita Tariyal

    2014-12-01

    Full Text Available The Himalayan region represents enormous variability of climates, hydrological and ecological systems, plus a diversity of cultures and communities. It is an essentiality to the ecological security of the Indian landmass, through providing forest cover, feeding recurrent rivers that are the source of potable water, irrigation, and hydropower, conserving biodiversity, providing a rich foundation for high value agriculture, and spectacular landscapes for sustainable tourism. Increasing concentration of greenhouse gases in the troposphere and the consequential global warming is posing a great environmental threat to water and food security at universal level. Change in climate may affect exposures to air pollutants by affecting weather, anthropogenic emissions, and by changing the distribution and types of airborne allergens. This potential variability in climate will have a serious impact on several ecosystem services, such as cleaning water and removing carbon from the atmosphere. Various services of ecosystems viz. land and water resources, agriculture, biodiversity will experience a wide range of stresses together with pests and pathogens, invasive species, atmospheric pollution, acute events, wildfires and floods. Direct stresses posed due to climate change may get intensified through high temperatures, reduced water availability, and altered frequency of extreme events and severe storms. Climate change will potentially make a threat on the availability of, and access to, water resources. The Himalayan ecosystem is vulnerable to the impacts and consequences of a changes on account of natural causes, b climate change resulting from human-induced emissions and c developmental paradigms of the modern society. Adaptation factors in the element of ‘sustainability’ into development initiatives and provides for additional measures and resources to safeguard environmental gains against climate impacts.

  9. Modelling impact of climate variability on rainfed groundnut

    OpenAIRE

    Gadgil, Sulochana; Rao, Seshagiri PR; Sridhar, S.

    1999-01-01

    We present here a heuristic model for the indirect impact of climate variability via the triggering of pests/diseases/weeds for rainfed groundnut over the Anantapur region. A simple hydrological model is used to determine the soil moisture for the rainfall pattern, in any given year. The criteria for determining when specific farming operations, such as ploughing and sowing, are performed are defined in terms of the soil moisture, on the basis of the farming practices in the region. With the ...

  10. Current climate variability and future climate change: Estimated growth and poverty impacts for Zambia

    OpenAIRE

    Thurlow, James; Zhu, Tingju; Diao, Xinshen

    2011-01-01

    Economy-wide and hydrological-crop models are combined to estimate and compare the economic impacts of current climate variability and future anthropogenic climate change in Zambia. Accounting for uncertainty, simulation results indicate that, on average, current variability reduces gross domestic product by four percent over a ten-year period and pulls over two percent of the population below the poverty line. Socio-economic impacts are much larger during major drought years, thus underscori...

  11. Climate variability, climate changes and their impact on water cycles

    International Nuclear Information System (INIS)

    Water availability in Pakistan particularly depends upon both summer and winter rainfall in plains and snowfall over the mountains. Climatically being located in subtropical region, the major amount of rainfall is in monsoon season, which extends from July, to September. Incidentally the deficient or surplus rainfall years are dependent upon intensity of Monsoon current. The same Monsoon current is also responsible for rainfall over the catchment area of eastern rivers i.e. Sutlej, Ravi, Chenab. These catchments are located across the border of eastern rivers. Westerly wave component is another aspect, responsible for rainfall in Jhelum and Indus River though some times Monsoon depressions penetrate up to Jhelum and give heavy rainfall along the route over the Eastern rivers causing the net surplus water availability. The rainfall pattern determines the agriculture output and the crops to be sown along with the area determination. This is particularly dictated by the different regimes of the Monsoon rainfall to mitigate both the surplus and deficient water availability, comprehensive study of statistical data indicates future reservoir/dam location, its construction, and a shift in crops pattern and water utility in commensurate with Climatological dictates in this region of south Asia. (Author)

  12. Climate variability and climate change

    International Nuclear Information System (INIS)

    Changes of variability with climate change are likely to have a substantial impact on vegetation and society, rivaling the importance of changes in the mean values themselves. A variety of paleoclimate and future climate simulations performed with the GISS global climate model is used to assess how the variabilities of temperature and precipitation are altered as climate warms or cools. In general, as climate warms, temperature variability decreases due to reductions in the latitudinal temperature gradient and precipitation variability increases together with the intensity of the hydrologic cycle. If future climate projections are accurate, the reduction in temperature variability will be minimized by the rapid change in mean temperatures, but the hydrologic variability will be amplified by increased evapotranspiration. Greater hydrologic variability would appear to pose a potentially severe problem for the next century. 19 refs.; 3 figs.; 2 tabs

  13. Climate variability and climate change

    International Nuclear Information System (INIS)

    Changes of variability with climate change are likely to have a substantial impact on vegetation and society, rivaling the importance of changes in the mean values themselves. A variety of paleoclimate and future climate simulations performed with the GISS global climate model is used to assess how the variabilities of temperature and precipitation are altered as climate warms or cools. In general, as climate warms, temperature variability decreases due to reductions in the latitudinal temperature gradient and precipitation variability increases together with the intensity of the hydrologic cycle. If future climate projections are accurate, the reduction in temperature variability will be minimized by the rapid change in mean temperatures, but the hydrologic variability will be amplified by increased evapotranspiration. Greater hydrologic variability would appear to pose a potentially severe problem for the next century

  14. Impacts of forced and unforced climate variability on extreme floods using a large climate ensemble

    Science.gov (United States)

    Martel, Jean-Luc; Brissette, François; Chen, Jie

    2016-04-01

    Frequency analysis has been widely used for the inference of flood magnitude and rainfall intensity required in engineering design. However, this inference is based on the concept of stationarity. How accurate is it when taking into account climate variability (i.e. both internal- and externally-forced variabilities)? Even in the absence of human-induced climate change, the short temporal horizon of the historical records renders this task extremely difficult to accomplish. To overcome this situation, large ensembles of simulations from a single climate model can be used to assess the impact of climate variability on precipitation and streamflow extremes. Thus, the objective of this project is to determine the reliability of return period estimates using the CanESM2 large ensemble. The spring flood annual maxima metric over snowmelt-dominated watersheds was selected to take into account the limits of global circulation models to properly simulate convective precipitation. The GR4J hydrological model coupled with the CemaNeige snow model was selected and calibrated using gridded observation datasets on snowmelt-dominated watersheds in Quebec, Canada. Using the hydrological model, streamflows were simulated using bias corrected precipitation and temperature data from the 50 members of CanESM2. Flood frequency analyses on the spring flood annual maxima were then computed using the Gumbel distribution with a 90% confidence interval. The 20-year return period estimates were then compared to assess the impact of natural climate variability over the 1971-2000 return period. To assess the impact of global warming, this methodology was then repeated for three time slices: reference period (1971-2000), near future (2036-2065) and far future (2071-2100). Over the reference period results indicate that the relative error between the return period estimates of two members can be up to 25%. Regarding the near future and far future periods, natural climate variability of extreme

  15. Climate Variability Impacts on Watershed Nutrient Delivery and Reservoir Production

    Science.gov (United States)

    White, J. D.; Prochnow, S. J.; Zygo, L. M.; Byars, B. W.

    2005-05-01

    Reservoirs in agricultural dominated watersheds tend to exhibit pulse-system behavior especially if located in climates dominated by summer convective precipitation inputs. Concentration and bulk mass of nutrient and sediment inputs into reservoir systems vary in terms of timing and magnitude of delivery from watershed sources to reservoirs under these climate conditions. Reservoir management often focuses on long-term average inputs without considering short and long-term impacts of variation in loading. In this study we modeled a watershed-reservoir system to assess how climate variability affects reservoir primary production through shifts in external loading and internal recycling of limiting nutrients. The Bosque watershed encompasses 423,824 ha in central Texas which delivers water to Lake Waco, a 2900 ha reservoir that is the primary water source for the city of Waco and surrounding areas. Utilizing the Soil Water Assessment Tool for the watershed and river simulations and the CE-Qual-2e model for the reservoir, hydrologic and nutrient dynamics were simulated for a 10 year period encompassing two ENSO cycles. The models were calibrated based on point measurement of water quality attributes for a two year time period. Results indicated that watershed delivery of nutrients was affected by the presence and density of small flood-control structure in the watershed. However, considerable nitrogen and phosphorus loadings were derived from soils in the upper watershed which have had long-term waste-application from concentrated animal feeding operations. During El Niño years, nutrient and sediment loads increased by 3 times above non-El Niño years. The simulated response within the reservoir to these nutrient and sediment loads had both direct and indirect. Productivity evaluated from chlorophyll a and algal biomass increased under El Niño conditions, however species composition shifts were found with an increase in cyanobacteria dominance. In non-El Niño years

  16. Impact of Climate Change and Variability on Crop Productivity

    Science.gov (United States)

    Jain, A. K.; Song, Y.

    2012-12-01

    Climate change, in terms of increasing levels of CO2, change in temperature and precipitation pattern, is directly influencing crop production through biophysical and phenology effects. At the same time crop production will also influence thermal energy and water exchange between land surface and atmosphere, and thus impact regional and global climate at long term time scale. Therefore, to satisfy the growing need of food production and realize sustainable agriculture under climate change, it is necessary to understand the complex interaction between crop productivity and climate change. While many research studies have been carried out on this area, there are still some unanswered key questions: How will changes in climate (temperature and precipitation) and atmospheric CO2 affect the regional crop yields for each crop types? Will there be a positive, negative, or insignificant interaction between crop yields and climate change? In which climate region(s) will the interaction be most pronounced? How rain-fed crop production will influence water balance between land surface and atmosphere, and thus its production potential? A land surface model with dynamic simulation of crop component (ISAM) has been developed and applied to address these questions. The ISAM model is a process-based, biogeophysical and biogeochemical model, which calculates dynamic crop growth processes as well as carbon, nitrogen, water and energy exchanges between soil, crop-system and atmosphere. The crop-system considered in current version of the ISAM includes corn and soybean. This study will specifically focus on the agricultural regions in the US. The potential productivity of these crops will be assessed under the various atmospheric CO2 and climate change conditions. This study will help to quantify the impact of various environmental factors on row crops and to better understand the spatial and temporal dynamics of crop yields under different climate change conditions.

  17. Impacts of climate change and variability on European agriculture

    DEFF Research Database (Denmark)

    Orlandini, Simone; Nejedlik, Pavol; Eitzinger, Josef;

    2008-01-01

    risk assessment and foreseen impacts on agriculture. The work will be carried out by respective Working Groups. This paper presents the results of the analysis of the first phase of inventory activity. Specific questionnaires were disseminated among COST 734 countries to collect information on climate...

  18. Climate variability impact assessment on the flood risk in Slovenia

    OpenAIRE

    Šraj, Mojca; Menih, Matevž; Bezak, Nejc

    2016-01-01

    Assessment of climate change or climate variability is a significant topic in most geophysical disciplines. In this study, the flood frequency approach was selected to analyze changes in flood series. Discharge data from 55 gaging stations in Slovenia were used. The annual maximum method was applied to define the samples. The data sets were divided into 30-year periods based on a 10-year moving window. For each part of the data-set, the flood frequency analysis was performed. Changes in the e...

  19. Climate variability impacts on rice crop production in pakistan

    International Nuclear Information System (INIS)

    The climate variability has affected the agriculture production all over the globe. This concern has motivated important changes in the field of research during the last decade. Climate changes are believed to have declining effects towards crop production in Pakistan. This study carries an empirical investigation of the effects of climate change on rice crop of Pakistan by employing Vector Auto Regression (VAR) model. Annual seasonal data of the climatic variables from 1980 to 2013 has been used. Results confirmed that rising mean maximum temperature would lead to reduction in rice production while increase in mean minimum temperature would be advantageous towards rice production. Variation in mean minimum temperature brought about seven percent increase in rice productivity as shown by Variance Decomposition. Mean precipitation and mean temperature would increase rice production but simulations scenarios for 2030 confirmed that much increase in rainfall and mean temperature in long run will negatively affect rice production in future. It is therefore important to follow adequate policy action to safeguard crop productions from disastrous effects. Development of varieties resistant to high temperatures as well as droughts will definitely enhance resilience of rice crop in Pakistan. (author)

  20. POTENTIAL IMPACTS OF CLIMATIC VARIABILITY ON INDIAN HIMALAYAN REGION

    OpenAIRE

    Kavita Tariyal; Dhanesh Mohan Bartwal

    2014-01-01

    The Himalayan region represents enormous variability of climates, hydrological and ecological systems, plus a diversity of cultures and communities. It is an essentiality to the ecological security of the Indian landmass, through providing forest cover, feeding recurrent rivers that are the source of potable water, irrigation, and hydropower, conserving biodiversity, providing a rich foundation for high value agriculture, and spectacular landscapes for sustainable tourism. Increasing concentr...

  1. Adapting to the impacts of climate change and variability

    International Nuclear Information System (INIS)

    A workshop was held to encourage awareness of the climate change impact issues and build collaboration among the Great Lakes/St. Lawrence basin (GLSLB) research, resource management, and policy-making community; to identify research opportunities to address the issues of water management, ecosystem health, human health, and land use and management; and to recommend directions and priority areas for future studies to develop an integrated climate impact assessment for the GLSLB. Presentations at the workshop were on topics including an overview of the GLSLB Project, the impacts of climate change on water supply and demand, and impacts on water quality, fisheries, wetlands, agriculture, shoreline management, and human health. Panel sessions were also convened to discuss information requirements that would assist in decision- and policy-making and to address the concept of integration. Working groups on water management, ecosystem health, land use and management, and human health were formed and made recommendations. A synthesis is presented of the reports from and recommendations of the four working groups as well as extended abstracts of the plenary presentations. A separate abstract has been prepared for one of the presentations from this workshop

  2. Australia: Climate-Ecosystem Variability and Impacts on Disease

    Science.gov (United States)

    Gustafson, K. C.; Diabate, M.; Anyamba, A.

    2012-12-01

    Climate variability in Australia is largely driven by an atmospheric phenomenon called the Southern Oscillation (SO), which involves a see-saw like behavior between low and high pressure systems within the equatorial Pacific regions. The interaction of SO with abnormally high sea surface temperatures (SSTs) - El Niño - or abnormally low SSTs - La Niña ("anti-El Niño") - creates extreme drought or extreme flooding respectively throughout the Australian continent. These El Niño-Southern Oscillation (ENSO) events have significant impacts on Australia's landscape, ecosystems, agriculture production, and, as this report show, human health. The teleconnection between ENSO and human health is straight forward but not obvious. During La Niña years, when ENSO events are characterized by increased rainfall and consequential flooding, Australia's tropical, warm climate in addition to an associated increase in vegetation growth from the increased rainfall creates an ideal habitat for mosquito population increase. Certain species of Australian mosquitoes [Culux annulirostris] are carriers of Murray Valley Encephalitis (MVE) virus which is a rare but potentially fatal infection that attacks neurological and muscular functioning. It is hypothesized that a widespread increase in vegetation indicates an expansion of ideal mosquito production habitats and will translate to an increased risk of MVE contraction. The objective of this research is to show if a correlation exists between the ENSO-driven climate- and consequential ecosystem- changes and MVE outbreaks throughout Australia. To do so, this study makes use of the Moderate Resolution Imaging Spectroradiometer (MODIS) sensor operating on NASA's Terra satellite to obtain monthly Normalized Difference Vegetation Index (NDVI) data. It is assumed in this research that an anomalous increase in NDVI values - indicative of vegetation growth - occurs as a result of increased rainfall. Due to Australia's tropical positioning and

  3. Impacts of Austrian Climate Variability on Honey Bee Mortality

    Science.gov (United States)

    Switanek, Matt; Brodschneider, Robert; Crailsheim, Karl; Truhetz, Heimo

    2015-04-01

    Global food production, as it is today, is not possible without pollinators such as the honey bee. It is therefore alarming that honey bee populations across the world have seen increased mortality rates in the last few decades. The challenges facing the honey bee calls into question the future of our food supply. Beside various infectious diseases, Varroa destructor is one of the main culprits leading to increased rates of honey bee mortality. Varroa destructor is a parasitic mite which strongly depends on honey bee brood for reproduction and can wipe out entire colonies. However, climate variability may also importantly influence honey bee breeding cycles and bee mortality rates. Persistent weather events affects vegetation and hence foraging possibilities for honey bees. This study first defines critical statistical relationships between key climate indicators (e.g., precipitation and temperature) and bee mortality rates across Austria, using 6 consecutive years of data. Next, these leading indicators, as they vary in space and time, are used to build a statistical model to predict bee mortality rates and the respective number of colonies affected. Using leave-one-out cross validation, the model reduces the Root Mean Square Error (RMSE) by 21% with respect to predictions made with the mean mortality rate and the number of colonies. Furthermore, a Monte Carlo test is used to establish that the model's predictions are statistically significant at the 99.9% confidence level. These results highlight the influence of climate variables on honey bee populations, although variability in climate, by itself, cannot fully explain colony losses. This study was funded by the Austrian project 'Zukunft Biene'.

  4. Climate variability: Possible changes with climate change and impacts on crop yields

    International Nuclear Information System (INIS)

    A pilot study was carried out of the sensitivity of the CERES wheat model, a deterministic crop-climate model, to changes in the interannual variability of temperature and precipitation. The study was designed to determine the effect of changed temperature variance on the mean and variance of the simulated yields, to compare the effect with the effect of mean temperature changes, and to determine the interacting effects of changes in mean and variance of temperature. The CERES model was applied to 29 cropping years (1952-1980), using three different soil types and two different management practices (fully irrigated and dryland). The coefficients of variation of the yields for irrigated and dryland conditions are plotted against variance change. It was found that in both management systems, the yield response is usually greater to increases rather than decreases in variance. The combined effect of mean and variance temperature changes are most striking under irrigated conditions, with a dramatic decrease in yield variability in the high mean climate change scenario with decreased temperature variance. This suggests that the variability decrease might mitigate the effect of a mean increase in temperature. This result is not found with the dryland case, where decreased temperature variability has little impact on yield variability. 12 refs., 4 figs

  5. Future climate variability impacts on potential erosion and soil organic carbon in European croplands

    OpenAIRE

    Van der Velde, M.; Balkovič, J.; Beer, C.; Khabarov, N.; M. Kuhnert; Obersteiner, M.; Skalský, R.; Xiong, W; Smith, P

    2014-01-01

    We investigate the impact of future climate variability on the potential vulnerability of soils to erosion and the consequences for soil organic carbon (SOC) in European croplands. Soil erosion is an important carbon flux not characterized in Earth System Models. We use a~European implementation of EPIC, driven by reference climate data (CNTRL), and climate data with reduced variability (REDVAR). Whether erosion regimes will change across European cropland d...

  6. Future climate variability impacts on potential erosion and soil organic carbon in European croplands

    Directory of Open Access Journals (Sweden)

    M. van der Velde

    2014-01-01

    Full Text Available We investigate the impact of future climate variability on the potential vulnerability of soils to erosion and the consequences for soil organic carbon (SOC in European croplands. Soil erosion is an important carbon flux not characterized in Earth System Models. We use a~European implementation of EPIC, driven by reference climate data (CNTRL, and climate data with reduced variability (REDVAR. Whether erosion regimes will change across European cropland depends on the spatial conjunction of expected changes in climate variability and physiographic conditions conducive to erosion. We isolated the effect of erosion by performing simulations with and without erosion. Median CNTRL and REDVAR erosion rates equalled 14.4 and 9.1 ton ha−1, and 19.1 and 9.7, for 1981–2010 and 2071–2100, respectively. The total amount of carbon lost from European cropland due to erosion was estimated at 769 Tg C for 1981–2010 (from a total storage of 6197 Tg C without erosion under CNTRL climate. Climate trend impacts reduce the European cropland SOC stock by 578 Tg C without – and by 683 Tg C with erosion, from 1981 to 2100. Climate variability compounds these impacts and decreases the stock by an estimated 170 Tg without erosion and by 314 Tg C with erosion, by the end of the century. Future climate variability and erosion will thus compound impacts on SOC stocks arising from gradual climate change alone.

  7. Assessing the impact of climate variability and human activities on streamflow variation

    OpenAIRE

    Chang, J.; Zhang, H.; Wang, Y.; Zhu, Y

    2015-01-01

    Water resources in river systems have been changing under the impact of both climate variability and human activities. Assessing the respective impact on decadal streamflow variation is important for water resource management. By using an elasticity-based method and calibrated TOPMODEL and VIC hydrological models, we quantitatively isolated the relative contributions that human activities and climate variability made to decadal streamflow changes in Jinghe basin, located in ...

  8. Assessing the impact of climate variability and human activity to streamflow variation

    OpenAIRE

    Chang, J.; Zhang, H.; Wang, Y.; Zhu, Y

    2015-01-01

    Water resources in river systems have been changing under the impacts of both climate variability and human activities. Assessing the respective impacts on decadal streamflow variation is important for water resources management. By using an elasticity-based method, calibrated TOPMODEL and VIC hydrologic models, we have quantitatively isolated the relative contributions that human activity and climate variability made to decadal streamflow changes in Jinhe b...

  9. Assessing the impact of climate variability and human activities on streamflow variation

    OpenAIRE

    Chang, Jianxia; Zhang, Hongxue; Wang, Yimin; Zhu, Yuelu

    2016-01-01

    Water resources in river systems have been changing under the impact of both climate variability and human activities. Assessing the respective impact on decadal streamflow variation is important for water resource management. By using an elasticity-based method and calibrated TOPMODEL and VIC hydrological models, we quantitatively isolated the relative contributions that human activities and climate variability made to decadal streamflow changes in the Jinghe basin, located...

  10. Impacts of Interannual Climate Variability on Agricultural and Marine Ecosystems

    Science.gov (United States)

    Cane, M. A.; Zebiak, S.; Kaplan, A.; Chen, D.

    2001-01-01

    The El Nino - Southern Oscillation (ENSO) is the dominant mode of global interannual climate variability, and seems to be the only mode for which current prediction methods are more skillful than climatology or persistence. The Zebiak and Cane intermediate coupled ocean-atmosphere model has been in use for ENSO prediction for more than a decade, with notable success. However, the sole dependence of its original initialization scheme and the improved initialization on wind fields derived from merchant ship observations proved to be a liability during 1997/1998 El Nino event: the deficiencies of wind observations prevented the oceanic component of the model from reaching the realistic state during the year prior to the event, and the forecast failed. Our work on the project was concentrated on the use of satellite data for improving various stages of ENSO prediction technology: model initialization, bias correction, and data assimilation. Close collaboration with other teams of the IDS project was maintained throughout.

  11. Climate Variability and Impact at NASA's Marshal Space Flight Center

    Science.gov (United States)

    Smoot, James L.; Jedlovec, Gary; Williams, Brett

    2013-01-01

    Climate analysis for the Southeast U. S. has indicated that inland regions have experienced an average temperature increase of 2F since 1970. This trend is generally characterized by warmer winters with an indication of increased precipitation in the Fall season. Extended periods of limited rainfall in the Spring and Summer periods have had greater areal coverage and, at other times the number of precipitation events has been increasing. Climate model projections for the next 10-70 years indicate warmer temperatures for the Southeast U.S., particularly in the Spring and Summer, with some indication of more extremes in temperature and precipitation as shown in the table below. The realization of these types of regional climate changes in the form of extended heat waves and droughts and their subsequent stress on facilities, infrastructure, and workforce could have substantial impact on the activities and functions of NASA's Marshall Space Flight Center (MSFC) in Huntsville, Alabama. This presentation will present the results of an examination of the 100 year temperature and precipitation record for MSFC. Local warming has cause an increase in daily maximum and minimum temperatures by nearly 3F, with a substantial increase in the number of maximum temperatures exceeding 90F and a decrease in the number of days with minimum temperatures below freezing. These trends have substantial impact of the number of heating / cooling degree days for the area. Yearly precipitation totals are inversely correlated with the change in mean temperature and the frequency of heavy rain events has remain consistent with the changes in yearly totals. An extended heat wave index was developed which shows an increase in frequency of heat waves over the last 35 years and a subsequent reduction in precipitation during the heat waves. This trend will contribute to more intense drought conditions over the northern Alabama region, increasing the potential of destructive wildfires in and around

  12. Economic perspectives on the impact of climate variability and change: A summary report

    International Nuclear Information System (INIS)

    A summary is presented of a collection of papers on the economic methodologies applicable to studies of the impact of global climate variability and change. The research was sponsored by the Canadian Climate program and was conducted as part of a project investigating the potential impacts on various sectors of the Canadian economy of climate warming due to the greenhouse effect. Topics of the papers include microeconomic analysis, benefit/cost analysis, input-output analysis, policy options regarding water levels in the Great Lakes, the scenario approach to assessing socio-economic sensitivities to climate change in the agri-food sector, and analysis of weather impacts. Several analytical tools are seen to be readily applicable to economic analyses of the effects of climate change, and issues of future water supply and demand are seen as central to climate impact assessment, and of particular concern to Canada

  13. Impact of spatial-temporal variations of climatic variables onsummer maize yield in North China Plain

    OpenAIRE

    Wu, D.; Yu, Q.; Wang, E; Hengsdijk, H.

    2008-01-01

    Summer maize (Zea mays L.) is one of the dominant crops in the North China Plain (NCP). Itsgrowth is greatly influenced by the spatial-temporal variation of climatic variables, especially solar radiation, temperature and rainfall. The WOFOST (version 7.1) model was applied to evaluate the impact of climatic variability on summer maize yields using historical meteorological data from 1961to 2000. The model was calibrated and validated using data from field experiments conducted duringthe perio...

  14. Assessing climate impacts

    OpenAIRE

    Wohl, Ellen E.; Roger S. Pulwarty; Zhang, Jian Yun

    2000-01-01

    Assessing climate impacts involves identifying sources and characteristics of climate variability, and mitigating potential negative impacts of that variability. Associated research focuses on climate driving mechanisms, biosphere–hydrosphere responses and mediation, and human responses. Examples of climate impacts come from 1998 flooding in the Yangtze River Basin and hurricanes in the Caribbean and Central America. Although we have limited understanding of the fu...

  15. Assessment of Impacts of Climate Variability on Crop Yield over the Terai Region of Nepal

    Science.gov (United States)

    Subedi, S.; Acharya, A.

    2015-12-01

    Agricultural sector in Nepal which alone contributes about 42 % of the total GDP have a huge influence on national economy. This sector is very much susceptible to climate change. This study is emphasized on Terai region (situated at an altitude of 60m to 300m) of Nepal which investigates the impacts of climate variability on various stages of cropping (paddy) periods such as transplant, maturity and harvest. The climate variables namely temperature and rainfall are used to explore the relationship between climate and paddy yields based on 30 years of historical observed data. Observed monthly rainfall and temperature data are collected from the department of hydrology and meteorology, and paddy yield data are collected from the Ministry of Agricultural Development. A correlation analysis will be carried out between the backward difference filtered climate parameters and the backward difference filtered rice yield. This study will also analyze average monthly and annual rainfall, and, min, max and mean temperature during the period of 1981-2010 based on 15 synoptic stations of Nepal. This study will visualize rainfall and temperature distribution over Nepal, and also evaluate the effect of change in rainfall and temperature in the paddy yield. While evaluating the impacts of climate on crop yield, this study will not consider the impact of irrigation in crop yield. The major results, climate distribution and its local/regional impacts on agriculture, could be utilized by planners, decision makers, and climate and agricultural scientists as a basis in formulating/implementing future plans, policies and projects.

  16. A modelling methodology for assessing the impact of climate variability and climatic change on hydroelectric generation

    International Nuclear Information System (INIS)

    A new methodology relating basic climatic variables to hydroelectric generation was developed. The methodology can be implemented in large or small basins with any number of hydro plants. The method was applied to the Sacramento, Eel and Russian river basins in northern California where more than 100 hydroelectric plants are located. The final model predicts the availability of hydroelectric generation for the entire basin provided present and near past climate conditions, with about 90% accuracy. The results can be used for water management purposes or for analyzing the effect of climate variability on hydrogeneration availability in the basin. A wide range of results can be obtained depending on the climate change scenario used. (Author)

  17. The impact of climate variability and change on economic growth and poverty in Zambia:

    OpenAIRE

    Thurlow, James; Zhu, Tingju; DIAO, Xinshen

    2009-01-01

    "We combined a hydro-crop model with a dynamic general equilibrium (DCGE) model to assess the impacts of climate variability and change on economic growth and poverty reduction in Zambia. The hydro-crop model is first used to estimate the impact of climate variability on crop yields over the past three decades and such analysis is done at the crop level for each of Zambia's five agroecological zones, supported by the identification of zonal-level extreme weather events using a drought index a...

  18. Assessing the impact of climate variability and human activity to streamflow variation

    Directory of Open Access Journals (Sweden)

    J. Chang

    2015-06-01

    Full Text Available Water resources in river systems have been changing under the impacts of both climate variability and human activities. Assessing the respective impacts on decadal streamflow variation is important for water resources management. By using an elasticity-based method, calibrated TOPMODEL and VIC hydrologic models, we have quantitatively isolated the relative contributions that human activity and climate variability made to decadal streamflow changes in Jinhe basin located in northwest of China. This is an important watershed of Shaanxi Province that supplies drinking water for a population of over 6 million. The results from the three methods show that both human activity and climatic differences can have major effects on catchment streamflow, and the estimates of climate variability impacts from the hydrological models are similar to those from the elasticity-based method. Compared with the baseline period of 1960–1970, streamflow greatly decreased during 2001–2010. The change impacts of human activity and climate variability in 2001–2010 were about 83.5 and 16.5% of the total reduction respectively when averaged over the three methods. The maximum contribution value of human activity was appeared in 1981–1990 due to the effects of soil and water conservation measures and irrigation water withdrawal, which was 95, 112.5 and 92.4% from TOPMODEL, VIC model and elasticity-based method respectively. The maximum value of the aridity index (E0/P was 1.91 appeared in 1991–2000. Compared with 1960–1970 baseline period, climate variability made the greatest contributions reduction in 1991–2000, which was 47.4, 43.9 and 29.9% from TOPMODEL, VIC model and elasticity-based method respectively. We emphasized various source of errors and uncertainties that may occurre in the hydrological model (parameter and structural uncertainty and elasticity-based method (model parameter in climate change impact studies.

  19. Assessing the impact of climate variability and human activity to streamflow variation

    Science.gov (United States)

    Chang, J.; Zhang, H.; Wang, Y.; Zhu, Y.

    2015-06-01

    Water resources in river systems have been changing under the impacts of both climate variability and human activities. Assessing the respective impacts on decadal streamflow variation is important for water resources management. By using an elasticity-based method, calibrated TOPMODEL and VIC hydrologic models, we have quantitatively isolated the relative contributions that human activity and climate variability made to decadal streamflow changes in Jinhe basin located in northwest of China. This is an important watershed of Shaanxi Province that supplies drinking water for a population of over 6 million. The results from the three methods show that both human activity and climatic differences can have major effects on catchment streamflow, and the estimates of climate variability impacts from the hydrological models are similar to those from the elasticity-based method. Compared with the baseline period of 1960-1970, streamflow greatly decreased during 2001-2010. The change impacts of human activity and climate variability in 2001-2010 were about 83.5 and 16.5% of the total reduction respectively when averaged over the three methods. The maximum contribution value of human activity was appeared in 1981-1990 due to the effects of soil and water conservation measures and irrigation water withdrawal, which was 95, 112.5 and 92.4% from TOPMODEL, VIC model and elasticity-based method respectively. The maximum value of the aridity index (E0/P) was 1.91 appeared in 1991-2000. Compared with 1960-1970 baseline period, climate variability made the greatest contributions reduction in 1991-2000, which was 47.4, 43.9 and 29.9% from TOPMODEL, VIC model and elasticity-based method respectively. We emphasized various source of errors and uncertainties that may occurre in the hydrological model (parameter and structural uncertainty) and elasticity-based method (model parameter) in climate change impact studies.

  20. Impacts of Climate Trends and Variability on Livestock Production in Brazil

    Science.gov (United States)

    Cohn, A.; Munger, J.; Gibbs, H.

    2015-12-01

    Cattle systems of Brazil are of major economic and environmental importance. They occupy ¼ of the land surface of the country, account for over 15 billion USD of annual revenue through the sale of beef, leather, and milk, are closely associated with deforestation, and have been projected to substantially grow in the coming decades. Sustainable intensification of production in the sector could help to limit environmental harm from increased production, but productivity growth could be inhibited by climate change. Gauging the potential future impacts of climate change on the Brazilian livestock sector can be aided by examining past evidence of the link between climate and cattle production and productivity. We use statistical techniques to investigate the contribution of climate variability and climate change to variability in cattle system output in Brazil's municipalities over the period 1974 to 2013. We find significant impacts of both temperature and precipitation variability and temperature trends on municipality-level exports and the production of both milk and beef. Pasture productivity, represented by a vegetation index, also varies significantly with climate shocks. In some regions, losses from exposure to climate trends were of comparable magnitude to technology and/or market-driven productivity gains over the study period.

  1. Improving plot- and regional-scale crop models for simulating impacts of climate variability and extremes

    Science.gov (United States)

    Tao, F.; Rötter, R.

    2013-12-01

    Many studies on global climate report that climate variability is increasing with more frequent and intense extreme events1. There are quite large uncertainties from both the plot- and regional-scale models in simulating impacts of climate variability and extremes on crop development, growth and productivity2,3. One key to reducing the uncertainties is better exploitation of experimental data to eliminate crop model deficiencies and develop better algorithms that more adequately capture the impacts of extreme events, such as high temperature and drought, on crop performance4,5. In the present study, in a first step, the inter-annual variability in wheat yield and climate from 1971 to 2012 in Finland was investigated. Using statistical approaches the impacts of climate variability and extremes on wheat growth and productivity were quantified. In a second step, a plot-scale model, WOFOST6, and a regional-scale crop model, MCWLA7, were calibrated and validated, and applied to simulate wheat growth and yield variability from 1971-2012. Next, the estimated impacts of high temperature stress, cold damage, and drought stress on crop growth and productivity based on the statistical approaches, and on crop simulation models WOFOST and MCWLA were compared. Then, the impact mechanisms of climate extremes on crop growth and productivity in the WOFOST model and MCWLA model were identified, and subsequently, the various algorithm and impact functions were fitted against the long-term crop trial data. Finally, the impact mechanisms, algorithms and functions in WOFOST model and MCWLA model were improved to better simulate the impacts of climate variability and extremes, particularly high temperature stress, cold damage and drought stress for location-specific and large area climate impact assessments. Our studies provide a good example of how to improve, in parallel, the plot- and regional-scale models for simulating impacts of climate variability and extremes, as needed for

  2. Human Health Impacts of and Public Health Adaptation to Climate Variability and Change

    Science.gov (United States)

    Ebi, K. L.

    2007-12-01

    Weather and climate are among the factors that determine the geographic range and incidence of several major causes of ill health, including undernutrition, diarrheal diseases and other conditions due to unsafe water and lack of basic sanitation, and malaria. The Human Health chapter in the Fourth Assessment Report of the Intergovernmental Panel on Climate Change concluded that climate change has begun to negatively affect human health, and that projected climate change will increase the risks of climate-sensitive health outcomes, particularly in lower-income populations, predominantly within tropical/subtropical countries. Those at greatest risk include the urban poor, older adults, children, traditional societies, subsistence farmers, and coastal populations, particularly in low income countries. The cause-and-effect chain from climate change to changing patterns of health determinants and outcomes is complex and includes socioeconomic, institutional, and other factors. The severity of future impacts will be determined by changes in climate as well as by concurrent changes in nonclimatic factors and by the adaptation measures implemented to reduce negative impacts. Public health has a long history of effectively intervening to reduce risks to the health of individuals and communities. Lessons learned from more than 150 years of research and intervention can provide insights to guide the design and implementation of effective and efficient interventions to reduce the current and projected impacts of climate variability and change.

  3. Potential Impacts of Land-Use on Climate Variability and Extremes

    Institute of Scientific and Technical Information of China (English)

    Huqiang ZHANG; LI Yaohui; GAO Xuejie

    2009-01-01

    This study aims at exploring potential impacts of land-use vegetation change (LUC) on regional climate variability and extremes.Results from a pair of Australian Bureau of Meteorology Research Centre (BMRC)climate model 54-yr (1949-2002) integrations have been analysed.In the model experiments,two vegetation datasets are used,with one representing current vegetation coverage in China and the other approximating its potential coverage without human intervention.The model results show potential impacts of LUC on climate variability and extremes.There are statistically significant changes of surface interannual climate variability simulated by the model.Using different vegetation datasets,significant changes in correlation coefficients between tropical Pacific Nifio3.4 SST and precipitation and surface temperature over East Asia are identified,which indicate that changes in vegetation coverage may alter ENSO impacts on regional climate variability.Because of the lack of slowly varying surface processes when forests are removed and less rainfall is received following LUC,the ENSO signal simulated by the model becomes stronger.Results furthermore show that land-use could modulate characteristics of decadal variations in this region.When using current vegetation coverage,the model gives better simulation of observed climate variations in the region than the case using potential vegetation coverage.In addition,results suggest that land-use could be a potential factor contributing to the prolonged drought in central-west China.Changes in local climate extremes,including precipitation and surface temperature maxima and minima,are also identified.Overall,this study has illustrated the importance of further investigation of such important issues in future land-use studies.

  4. Recent variability of the solar spectral irradiance and its impact on climate modelling

    CERN Document Server

    Ermolli, I; de Wit, T Dudok; Krivova, N A; Tourpali, K; Weber, M; Unruh, Y C; Gray, L; Langematz, U; Pilewskie, P; Rozanov, E; Schmutz, W; Shapiro, A; Solanki, S K; Woods, T N

    2013-01-01

    The lack of long and reliable time series of solar spectral irradiance (SSI) measurements makes an accurate quantification of solar contributions to recent climate change difficult. Whereas earlier SSI observations and models provided a qualitatively consistent picture of the SSI variability, recent measurements by the SORCE satellite suggest a significantly stronger variability in the ultraviolet (UV) spectral range and changes in the visible and near-infrared (NIR) bands in anti-phase with the solar cycle. A number of recent chemistry-climate model (CCM) simulations have shown that this might have significant implications on the Earth's atmosphere. Motivated by these results, we summarize here our current knowledge of SSI variability and its impact on Earth's climate. We present a detailed overview of existing SSI measurements and provide thorough comparison of models available to date. SSI changes influence the Earth's atmosphere, both directly, through changes in shortwave (SW) heating and therefore, temp...

  5. Impacts of Present and Future Climate Variability On Agriculture and Forestry in the Humid and Sub-Humid Tropics

    International Nuclear Information System (INIS)

    Although there are different results from different studies, most assessments indicate that climate variability would have negative effects on agriculture and forestry in the humid and sub-humid tropics. Cereal crop yields would decrease generally with even minimal increases in temperature. For commercial crops, extreme events such as cyclones, droughts and floods lead to larger damages than only changes of mean climate. Impacts of climate variability on livestock mainly include two aspects; impacts on animals such as increase of heat and disease stress-related death, and impacts on pasture. As to forestry, climate variability would have negative as well as some positive impacts on forests of humid and sub-humid tropics. However, in most tropical regions, the impacts of human activities such as deforestation will be more important than climate variability and climate change in determining natural forest cover

  6. Assessing Portuguese Guadiana Basin water management impacts under climate change and paleoclimate variability

    Science.gov (United States)

    Maia, Rodrigo; Oliveira, Bruno; Ramos, Vanessa; Brekke, Levi

    2014-05-01

    The water balance in each reservoir and the subsequent, related, water resource management decisions are, presently, highly information dependent and are therefore often limited to a reactive response (even if aimed towards preventing future issues regarding the water system). Taking advantage of the availability of scenarios for climate projections, it is now possible to estimate the likely future evolution of climate which represents an important stepping stone towards proactive, adaptative, water resource management. The purpose of the present study was to assess the potential effects of climate change in terms of temperature, precipitation, runoff and water availability/scarcity for application in water resource management decisions. The analysis here presented was applied to the Portuguese portion of the Guadiana River Basin, using a combination of observed climate and runoff data and the results of the Global Climate Models. The Guadiana River Basin was represented by its reservoirs on the Portuguese portion of the basin and, for the future period, an estimated value of the inflows originating in the Spanish part of the Basin. The change in climate was determined in terms of relative and absolute variations of climate (precipitation and temperature) and hydrology (runoff and water balance related information). Apart from the previously referred data, an hydrological model and a water management model were applied so as to obtain an extended range of data regarding runoff generation (calibrated to observed data) and water balance in the reservoirs (considering the climate change impacts in the inflows, outflows and water consumption). The water management model was defined in order to represent the reservoirs interaction including upstream to downstream discharges and water transfers. Under the present climate change context, decision-makers and stakeholders are ever more vulnerable to the uncertainties of climate. Projected climate in the Guadiana basin

  7. Impacts of Climate Variability on Latin American Small-scale Fisheries

    Directory of Open Access Journals (Sweden)

    Omar Defeo

    2013-12-01

    Full Text Available Small-scale fisheries (SSFs are social-ecological systems that play a critical role in terms of food security and poverty alleviation in Latin America. These fisheries are increasingly threatened by anthropogenic and climatic drivers acting at multiple scales. We review the effects of climate variability on Latin American SSFs, and discuss the combined effects of two additional human drivers: globalization of markets and governance. We show drastic long-term and large-scale effects of climate variability, e.g., sea surface temperature anomalies, wind intensity, sea level, and climatic indices, on SSFs. These variables, acting in concert with economic drivers, have exacerbated stock depletion rates in Latin American SSFs. The impact of these drivers varied according to the life cycle and latitudinal distribution of the target species, the characteristics of the oceanographic systems, and the inherent features of the social systems. Our review highlights the urgent need to improve management and governance systems to promote resilience as a way to cope with the increasing uncertainty about the impacts of climate and globalization of markets on Latin American SSFs.

  8. Tools for Assessing the Impacts of Climate Variability and Change on Wildfire Regimes in Forests

    Directory of Open Access Journals (Sweden)

    Hety Herawati

    2015-04-01

    Full Text Available Fire is an intrinsic element of many forest ecosystems; it shapes their ecological processes, determines species composition and influences landscape structure. However, wildfires may: have undesirable effects on biodiversity and vegetation coverage; produce carbon emissions to the atmosphere; release smoke affecting human health; and cause loss of lives and property. There have been increasing concerns about the potential impacts of climate variability and change on forest fires. Climate change can alter factors that influence the occurrence of fire ignitions, fuel availability and fuel flammability. This review paper aims to identify tools and methods used for gathering information about the impacts of climate variability and change on forest fires, forest fuels and the probability of fires. Tools to assess the impacts of climate variability and change on forest fires include: remote sensing, dynamic global vegetation and landscape models, integrated fire-vegetation models, fire danger rating systems, empirical models and fire behavior models. This review outlines each tool in terms of its characteristics, spatial and temporal resolution, limitations and applicability of the results. To enhance and improve tool performance, each must be continuously tested in all types of forest ecosystems.

  9. Assessing the impact of climate variability and human activities on streamflow variation

    Science.gov (United States)

    Chang, Jianxia; Zhang, Hongxue; Wang, Yimin; Zhu, Yuelu

    2016-04-01

    Water resources in river systems have been changing under the impact of both climate variability and human activities. Assessing the respective impact on decadal streamflow variation is important for water resource management. By using an elasticity-based method and calibrated TOPMODEL and VIC hydrological models, we quantitatively isolated the relative contributions that human activities and climate variability made to decadal streamflow changes in the Jinghe basin, located in the northwest of China. This is an important watershed of the Shaanxi province that supplies drinking water for a population of over 6 million people. The results showed that the maximum value of the moisture index (E0/P) was 1.91 and appeared in 1991-2000, and the decreased speed of streamflow was higher since 1990 compared with 1960-1990. The average annual streamflow from 1990 to 2010 was reduced by 26.96 % compared with the multiyear average value (from 1960 to 2010). The estimates of the impacts of climate variability and human activities on streamflow decreases from the hydrological models were similar to those from the elasticity-based method. The maximum contribution value of human activities was 99 % when averaged over the three methods, and appeared in 1981-1990 due to the effects of soil and water conservation measures and irrigation water withdrawal. Climate variability made the greatest contribution to streamflow reduction in 1991-2000, the values of which was 40.4 %. We emphasized various source of errors and uncertainties that may occur in the hydrological model (parameter and structural uncertainty) and elasticity-based method (model parameter) in climate change impact studies.

  10. [Environmental pollution, climate variability and climate change: a review of health impacts on the Peruvian population].

    Science.gov (United States)

    Gonzales, Gustavo F; Zevallos, Alisson; Gonzales-Castañeda, Cynthia; Nuñez, Denisse; Gastañaga, Carmen; Cabezas, César; Naeher, Luke; Levy, Karen; Steenland, Kyle

    2014-01-01

    This article is a review of the pollution of water, air and the effect of climate change on the health of the Peruvian population. A major air pollutant is particulate matter less than 2.5 μ (PM 2.5). In Lima, 2,300 premature deaths annually are attributable to this pollutant. Another problem is household air pollution by using stoves burning biomass fuels, where excessive indoor exposure to PM 2.5 inside the household is responsible for approximately 3,000 annual premature deaths among adults, with another unknown number of deaths among children due to respiratory infections. Water pollution is caused by sewage discharges into rivers, minerals (arsenic) from various sources, and failure of water treatment plants. In Peru, climate change may impact the frequency and severity of El Niño Southern Oscillation (ENSO), which has been associated with an increase in cases of diseases such as cholera, malaria and dengue. Climate change increases the temperature and can extend the areas affected by vector-borne diseases, have impact on the availability of water and contamination of the air. In conclusion, Peru is going through a transition of environmental risk factors, where traditional and modern risks coexist and infectious and chronic problems remain, some of which are associated with problems of pollution of water and air. PMID:25418656

  11. Evaluating the variability in surface water reservoir planning characteristics during climate change impacts assessment

    Science.gov (United States)

    Soundharajan, Bankaru-Swamy; Adeloye, Adebayo J.; Remesan, Renji

    2016-07-01

    This study employed a Monte-Carlo simulation approach to characterise the uncertainties in climate change induced variations in storage requirements and performance (reliability (time- and volume-based), resilience, vulnerability and sustainability) of surface water reservoirs. Using a calibrated rainfall-runoff (R-R) model, the baseline runoff scenario was first simulated. The R-R inputs (rainfall and temperature) were then perturbed using plausible delta-changes to produce simulated climate change runoff scenarios. Stochastic models of the runoff were developed and used to generate ensembles of both the current and climate-change-perturbed future runoff scenarios. The resulting runoff ensembles were used to force simulation models of the behaviour of the reservoir to produce 'populations' of required reservoir storage capacity to meet demands, and the performance. Comparing these parameters between the current and the perturbed provided the population of climate change effects which was then analysed to determine the variability in the impacts. The methodology was applied to the Pong reservoir on the Beas River in northern India. The reservoir serves irrigation and hydropower needs and the hydrology of the catchment is highly influenced by Himalayan seasonal snow and glaciers, and Monsoon rainfall, both of which are predicted to change due to climate change. The results show that required reservoir capacity is highly variable with a coefficient of variation (CV) as high as 0.3 as the future climate becomes drier. Of the performance indices, the vulnerability recorded the highest variability (CV up to 0.5) while the volume-based reliability was the least variable. Such variabilities or uncertainties will, no doubt, complicate the development of climate change adaptation measures; however, knowledge of their sheer magnitudes as obtained in this study will help in the formulation of appropriate policy and technical interventions for sustaining and possibly enhancing

  12. Impact of bushfire and climate variability on streamflow from forested catchments in southeast Australia

    Directory of Open Access Journals (Sweden)

    Y. Zhou

    2013-04-01

    Full Text Available Most of the surface water for natural environmental and human water uses in southeast Australia is sourced from forested catchments located in the higher rainfall areas. Water yield of these catchments is mainly affected by climatic conditions, but it is also greatly affected by vegetation cover change. Bushfires are a major natural disturbance in forested catchments and potentially modify the water yield of the catchments through changes to evapotranspiration (ET, interception and soil moisture storage. This paper quantifies the impacts of bushfire and climate variability on streamflow from three southeast Australian catchments where Ash Wednesday bushfires occurred in February 1983. The hydrological models used here include AWRA-L, Xinanjiang and GR4J. The three models are first calibrated against streamflow data from the pre-bushfire period and they are used to simulate runoff for the post-bushfire period with the calibrated parameters. The difference between the observed and model simulated runoff for the post-bushfire period provides an estimate of the impact of bushfire on streamflow. The hydrological modelling results for the three catchments indicate that there is a substantial increase in streamflow in the first 15 yr after the 1983 bushfires. The increase in streamflow is attributed to initial decreases in ET and interception resulting from the fires, followed by logging activity. After 15 yr, streamflow dynamics are more heavily influenced by climate effects, although some impact from fire and logging regeneration may still occur. It is shown that hydrological models provide reasonable consistent estimates of forest disturbance and climate impacts on streamflow for the three catchments. The results might be used by forest managers to understand the relationship between forest disturbance and climate variability impacts on water yield in the context of climate change.

  13. COST 734-CLIVAGRI: Impacts of Climate change and Variability on European Agriculture

    Science.gov (United States)

    Orlandini, S.; Nejedlik, P.; Eitzinger, J.; Alexandrov, V.; Toulios, L.; Kajfez Bogataj, L.; Calanca, P.; Trnka, M.; Olesen, J. E.

    2009-09-01

    COST is an intergovernmental framework for European Cooperation in Science and Technology, funded by its member countries through the EU Framework Programme. The objective of COST is to coordinate, integrate and synthesise results from ongoing national research within and between COST member countries to add value to research investment. COST Actions aim to deliver scientific syntheses and analyses of best available practice to aid problem identification, risk assessment, public utilities and policy development. During 2006, COST Action 734 (CLIVAGRI-Impacts of Climate Change and Variability on European Agriculture) was launched thanks to the coordinated activity of 15 EU countries. The main objective of the Action is the evaluation of possible impacts from climate change and variability on agriculture and the assessment of critical thresholds for various European areas (COST 734 MoU. www.cost.esf.org). Secondary objectives are: the collection and review of existing agroclimatic indices and simulation models, to assess hazard impacts on various European agricultural areas relating hazards to climatic conditions; building climate scenarios for the next few decades; the definition of harmonised criteria to evaluate the impacts of climate change and variability on agriculture; the definition of warning systems guidelines. Four working groups, with the integration of remote sensing sub working group 2.1 were created to address these aims: WG1 - Agroclimatic indices and simulation models WG2 - Evaluation of the current trends of agroclimatic indices and simulation model outputs describing agricultural impacts and hazard levels WG3 - Development and assessment of future regional and local scenarios of agroclimatic conditions WG4 - Risk assessment and foreseen impacts on agriculture The activity of WGs has been structured like a matrix, presenting on the rows the methods of analysis and on the columns the phenomena and the hazards. Each intersection point describes the

  14. Impacts of Present and Future Climate Variability on Agriculture and Forestry in the Temperate Regions. Europe

    International Nuclear Information System (INIS)

    Agriculture and forestry will be particularly sensitive to changes in mean climate and climate variability in the northern and southern regions of Europe. Agriculture may be positively affected by climate change in the northern areas through the introduction of new crop species and varieties, higher crop production and expansion of suitable areas for crop cultivation. The disadvantages may be determined by an increase in need for plant protection, risk of nutrient leaching and accelerated breakdown of soil organic matter. In the southern areas the benefits of the projected climate change will be limited, while the disadvantages will be predominant. The increased water use efficiency caused by increasing CO2 will compensate for some of the negative effects of increasing water limitation and extreme weather events, but lower harvestable yields, higher yield variability and reduction in suitable areas of traditional crops are expected for these areas. Forestry in the Mediterranean region may be mainly affected by increases in drought and forest fires. In northern Europe, the increased precipitation is expected to be large enough to compensate for the increased evapotranspiration. On the other hand, however, increased precipitation, cloudiness and rain days and the reduced duration of snow cover and soil frost may negatively affect forest work and timber logging determining lower profitability of forest production and a decrease in recreational possibilities. Adaptation management strategies should be introduced, as effective tools, to reduce the negative impacts of climate change on agricultural and forestry sectors

  15. Climate variability and vulnerability to climate change: a review

    OpenAIRE

    Thornton, Philip K.; Polly J Ericksen; Herrero, Mario; Challinor, Andrew J.

    2014-01-01

    The focus of the great majority of climate change impact studies is on changes in mean climate. In terms of climate model output, these changes are more robust than changes in climate variability. By concentrating on changes in climate means, the full impacts of climate change on biological and human systems are probably being seriously underestimated. Here, we briefly review the possible impacts of changes in climate variability and the frequency of extreme events on biological and food syst...

  16. Assessing the Impact of Climate Variability on Cropland Productivity in the Canadian Prairies Using Time Series MODIS FAPAR

    OpenAIRE

    Taifeng Dong; Jiangui Liu; Jiali Shang; Budong Qian; Ted Huffman; Yinsuo Zhang; Catherine Champagne; Bahram Daneshfar

    2016-01-01

    Cropland productivity is impacted by climate. Knowledge on spatial-temporal patterns of the impacts at the regional scale is extremely important for improving crop management under limiting climatic factors. The aim of this study was to investigate the effects of climate variability on cropland productivity in the Canadian Prairies between 2000 and 2013 based on time series of MODIS (Moderate Resolution Imaging Spectroradiometer) FAPAR (Fraction of Absorbed Photosynthetically Active Radiation...

  17. Evaluating Impact of Land Use Changes and Climate Variability on Economic Efficiency of Farming in Transboundary Watershed of Timor Island

    OpenAIRE

    Werenfridus Taena; Lala M. Kolopaking; Bambang Juanda; Baba Barus; Rizaldi Boer

    2016-01-01

    Indonesia and Timor-Leste development of border regions in Timor Island has brought land use changes, and when combined with climate variability it may cause flooding, drought, and impact of economic efficiency of farm crop. The research aimed to analyze: (i) the effect of land use changes and climate variability on the floods and drought on the Tono Watershed, (ii) the impact of flood, drought and production factors in yield and the economic efficiency of food crop farming. The analysis appl...

  18. Assessing the Impact of Climatic Variability and Change on Maize Production in the Midwestern USA

    Science.gov (United States)

    Andresen, J.; Jain, A. K.; Niyogi, D. S.; Alagarswamy, G.; Biehl, L.; Delamater, P.; Doering, O.; Elias, A.; Elmore, R.; Gramig, B.; Hart, C.; Kellner, O.; Liu, X.; Mohankumar, E.; Prokopy, L. S.; Song, C.; Todey, D.; Widhalm, M.

    2013-12-01

    Weather and climate remain among the most important uncontrollable factors in agricultural production systems. In this study, three process-based crop simulation models were used to identify the impacts of climate on the production of maize in the Midwestern U.S.A. during the past century. The 12-state region is a key global production area, responsible for more than 80% of U.S. domestic and 25% of total global production. The study is a part of the Useful to Useable (U2U) Project, a USDA NIFA-sponsored project seeking to improve the resilience and profitability of farming operations in the region amid climate variability and change. Three process-based crop simulation models were used in the study: CERES-Maize (DSSAT, Hoogenboom et al., 2012), the Hybrid-Maize model (Yang et al., 2004), and the Integrated Science Assessment Model (ISAM, Song et al., 2013). Model validation was carried out with individual plot and county observations. The models were run with 4 to 50 km spatial resolution gridded weather data for representative soils and cultivars, 1981-2012, to examine spatial and temporal yield variability within the region. We also examined the influence of different crop models and spatial scales on regional scale yield estimation, as well as a yield gap analysis between observed and attainable yields. An additional study was carried out with the CERES-Maize model at 18 individual site locations 1901-2012 to examine longer term historical trends. For all simulations, all input variables were held constant in order to isolate the impacts of climate. In general, the model estimates were in good agreement with observed yields, especially in central sections of the region. Regionally, low precipitation and soil moisture stress were chief limitations to simulated crop yields. The study suggests that at least part of the observed yield increases in the region during recent decades have occurred as the result of wetter, less stressful growing season weather conditions.

  19. Impacts of Changing Climate on Agricultural Variability: Implications for Smallholder Farmers in India

    Science.gov (United States)

    Mondal, P.; Jain, M.; DeFries, R. S.; Galford, G. L.; Small, C.

    2013-12-01

    Agriculture is the largest employment sector in India, where food productivity, and thus food security, is highly dependent on seasonal rainfall and temperature. Projected increase in temperature, along with less frequent but intense rainfall events, will have a negative impact on crop productivity in India in the coming decades. These changes, along with continued ground water depletion, could have serious implications for Indian smallholder farmers, who are among some of the most vulnerable communities to climatic and economic changes. Hence baseline information on agricultural sensitivity to climate variability is important for strategies and policies that promote adaptation to climate variability. This study examines how cropping patterns in different agro-ecological zones in India respond to variations in precipitation and temperature. We specifically examine: a) which climate variables most influence crop cover for monsoon and winter crops? and b) how does the sensitivity of crop cover to climate variability vary in different agro-ecological regions with diverse socio-economic factors? We use remote sensing data (2000-01 - 2012-13) for cropping patterns (developed using MODIS satellite data), climate parameters (derived from MODIS and TRMM satellite data) and agricultural census data. We initially assessed the importance of these climate variables in two agro-ecoregions: a predominantly groundwater irrigated, cash crop region in western India, and a region in central India primarily comprised of rain-fed or surface water irrigated subsistence crops. Seasonal crop cover anomaly varied between -25% and 25% of the 13-year mean in these two regions. Predominantly climate-dependent region in central India showed high anomalies up to 200% of the 13-year crop cover mean, especially during winter season. Winter daytime mean temperature is overwhelmingly the most important climate variable for winter crops irrespective of the varied biophysical and socio

  20. Climate variability and change in Ethiopia : exploring impacts and adaptation options for cereal production

    NARCIS (Netherlands)

    Kassie, B.T.

    2014-01-01

    Key words: Climate change, Adaptation, Crop modelling, Uncertainty, Maize (Zea mays), Central Rift Valley. Smallholder farmers in Ethiopia have been facing severe climate related hazards, in particular highly variable rainfall and severe droughts that negativelyaffect their livelihoods.Anticipated

  1. Assessing the impact of climate variability and change on crop production in the Midwestern USA

    Science.gov (United States)

    Wang, R.; Bowling, L. C.; Cherkauer, K. A.

    2013-12-01

    Interannual variability of crop yield in the Midwestern USA is closely related to extremes in spring and summer moisture conditions. For example, extensive summer drought in 2012 caused a 28% reduction in corn yield relative to early season predictions. In contrast, saturated soil conditions in spring 2013 have led to delayed planting and poor stand development. Therefore, when applying physically-based models to predict crop yield, soil moisture dynamics and physiological stresses must be correctly represented, especially under future climate scenarios where spring and summer moisture are projected to increase and decrease, respectively, over much of the Midwest. The overall objective of this research is to explore and improve the ability of an existing ecohydrology model (SWAT 2009) to simulate corn yield with respect to current and future climate and soil moisture variability. The model is first evaluated for four field scale sites in Iowa, Illinois and Ohio. Soil moisture is calibrated based on 5-6 years of layer specific data to ensure a realistic soil water representation either in dry or wet conditions. Then the calibrated model is used to evaluate the effects of climate variability on crop yield between 1991 and 2010. Finally, the model is run with down-scaled and bias-corrected CMIP5 data from three GCMs (CCSM4, GFDL-esm2m, MIROC5) and four emissions scenarios (RC2.6, RCP4.5, RCP6.0 and RCP8.5). Soil moisture, physiological stresses and crop yield predictions for two future periods (2031-2050, 2071-2090) are compared with the baseline period (1991-2010) to quantify climate change impacts on crop yield due to excess/deficit moisture.

  2. Present and Historical Climate Variability and its Ecological Impact on Vegetation in South West England

    Science.gov (United States)

    (Sasha) Kosanic, Aleksandra; Harrison, Stephan; Anderson, Karen; Turkington, Thea

    2014-05-01

    West Cornwall is the most south westerly part of the United Kingdom with a strong maritime climate. This study analyses the earliest archived instrumental meteorological records collected in West Cornwall (SW England). Records were obtained from the Met Office archive (Camborne 1957-2010; Culdrose 1985-2011), Trengwainton Garden (1940-2010), and from the Royal Cornwall Polytechnic Society, data for Falmouth (1880-1952) and Helston (1843-1888). Homogeneity tests were used (Levene and Brown-Forsythe tests) to exclude any trends not related to climate variability. The data exhibit trends in annual mean and maximum temperatures over the timescales analysed, and show a general temperature increase in the 20th and 21st century. Annual and seasonal temperature changes are found to vary locally with strongly positive trends in autumn, spring and summer seasons. Trends in precipitation are positive only for the 19th century and only for one station. Correlation with the North Atlantic Oscillation (NAO) index shows negative results for precipitation data. However correlation with the NAO index is positive with temperature, especially in the winter season. Return period analysis showed a decrease in intensity and frequency of extreme precipitation events in the post-1975 period (Camborne and Trengwainton Garden stations). Climate change in the 20th century, and future continued warming is likely to have major implications on biodiversity in this region. The second part of this research analyses changes in the geographical distribution of plant species over West Cornwall using herbarium and current vegetation records. Also we examine whether Ellenberg values could be used as an environmental change indicator. This research will clearly contribute to a better identification of the climate change impact in West Cornwall, but will also benefit policy developing strategies to identify areas at risk of climate impacts at the regional and local scale.

  3. Recent variability of the solar spectral irradiance and its impact on climate modelling

    Directory of Open Access Journals (Sweden)

    I. Ermolli

    2012-09-01

    Full Text Available During periods of high solar activity, the Earth receives ≈ 0.1% higher total solar irradiance (TSI than during low activity periods. Variations of the solar spectral irradiance (SSI however, can be larger, with relative changes of 1 to 20% observed in the ultraviolet (UV band, and in excess of 100% in the soft X-ray range. SSI changes influence the Earth's atmosphere, both directly, through changes in shortwave (SW heating and therefore, temperature and ozone distributions in the stratosphere, and indirectly, through dynamical feedbacks. Lack of long and reliable time series of SSI measurements makes the accurate quantification of solar contributions to recent climate change difficult. In particular, the most recent SSI measurements show a larger variability in the UV spectral range and anomalous changes in the visible and near-infrared (NIR bands with respect to those from earlier observations and from models. A number of recent studies based on chemistry-climate model (CCM simulations discuss the effects and implications of these new SSI measurements on the Earth's atmosphere, which may depart from current expectations.

    This paper summarises our current knowledge of SSI variability and its impact on Earth's climate. An interdisciplinary analysis of the topic is given. New comparisons and discussions are presented on the SSI measurements and models available to date, and on the response of the Earth's atmosphere and climate to SSI changes in CCM simulations. In particular, the solar induced differences in atmospheric radiative heating, temperature, ozone, mean zonal winds, and surface signals are investigated in recent simulations using atmospheric models forced with the current lower and upper boundaries of SSI solar cycle estimated variations from the NRLSSI model data and from SORCE/SIM measurements, respectively. Additionally, the reliability of available data is discussed and additional coordinated CCM experiments are proposed.

  4. Climate change and climate variability impacts on rainfed agricultural activities and possible adaptation measures. A Mexican case study

    Energy Technology Data Exchange (ETDEWEB)

    Conde, C.; Ferrer, R. [Centro de Ciencias de la Atmosfera, Universidad Nacional Autonoma de Mexico Circuito Exterior, Mexico, D.F. (Mexico)]. E-mail: e-mail: conde@servidor.unam.mx; Orozco, S. [Escuela de Agrobiologia, Universidad Autonoma de Tlaxcala, Tlaxcala (Mexico)

    2006-07-15

    Climate extreme events (such as those associated to strong El Nino events) highly affect Mexican agriculture, since more than sixty percent of it is rainfed. The basic crop cultivated is maize, which is still the main source of nutrients for a large portion of the rural population in the country. Within the project Capacity Building for Stage II Adaptation to Climate Change in Central America, Mexico and Cuba, we analyze the strategies developed by maize producers in the central region of the country to cope with climatic adverse events. Impact on rainfed maize due to climate variability and climate change conditions are studied using a crop simulation model. Several adaptation measures can be evaluated using that model. However, the effect of other stressors must be considered in an assessment of the adaptive capacity of small farmers to climate variability and change. Key stakeholders' involvement in the region helped us to decide which of the adaptive measures could be viable under the current conditions and under future climatic conditions. The construction of greenhouses, the use of compost, and dripping irrigation, were some of the techniques selected with the participation of the stakeholders. The enthusiastic responses to these measures allow us to consider that they can prevail in the future, under climate change conditions. However, the adaptation to climate change includes -besides the stated techniques- the generation of the capacities to cope with climatic adverse events, that is, to enhance the adaptive capacities to climate change among the key stakeholders. [Spanish] Los eventos climaticos extremos (como los asociados con eventos fuertes de El Nino) afectan de manera importante a la agricultura mexicana, ya que mas del sesenta por ciento de ella es de temporal, esto es, depende fundamentalmente de una buena temporada de lluvias para producir. El cultivo que se siembra es basicamente maiz, que todavia es la principal fuente de nutrientes para

  5. Impact of Climate Variability on the Hydrogeochemistry of Ecologically Important Prairie Wetlands and Lakes

    Science.gov (United States)

    Goldhaber, M. B.; Mills, C. T.; Mushet, D. M.; Stricker, C. A.; Rover, J.

    2015-12-01

    The Prairie Pothole region encompasses 715,000 km2 of the north central US and south central Canada and contains millions of small wetlands and lakes. It sustains large populations of shore birds and migratory waterfowl. PPR ecology is influenced by wetland geochemistry, which can range dramatically over short distances (≤ 200m) from dilute Ca2+-HCO3- to saline Na+-Mg2+-SO42- compositions. These compositional differences result, in part, from long-term critical zone processes in upland areas coupled to groundwater inflow, but they are also influenced by climate. Climate impacts on the geochemistry of 167 wetlands/lakes from a 9700 km2 area of North Dakota (USA) were studied. The chemical composition of these wetlands was determined in the early 1970's during slightly dry climatic conditions and again in 2012-2013, a period of exceptional precipitation. Dilution dominated wetland geochemical trends. Concentrations of Cl-, Na+, K+, and Mg2+ generally decreased in 2012-2013 compared to earlier data. In contrast Ca2+ increased, and SO42- change was variable. The processes driving these modifications were evaluated using inverse (mass balance based) geochemical modeling. The decrease in the largely inert ion, Na+ by rainwater addition was used to approximate the net dilution factor of the wetlands which ranged to >9. This volume increase was associated with large expansions of wetland area determined from time-series Landsat data. Introducing dissolution of authigenic CaCO3, a known constituent of wetland sediments, matched the observed Ca2+ increase. Addition of SO42--enriched groundwater (composition determined from well analyses) was required to model wetlands with increased SO42-. Those wetlands with increased SO42- had more negative δ34SSO4 values, a result consistent with a previously established isotopically light marine pyrite source for groundwater SO42-. Understanding the evolution of wetland chemistry may aid in assessing future climatic impacts to the PPR.

  6. Impacts of Present and Future Climate Change and Climate Variability on Agriculture in the Temperate Regions. North America

    International Nuclear Information System (INIS)

    The potential impact of climate variability and climate change on agricultural production in the United States and Canada varies generally by latitude. Largest reductions are projected in southern crop areas due to increased temperatures and reduced water availability. A longer growing season and projected increases in CO2 may enhance crop yields in northern growing areas. Major factors in these scenarios analyzes are increased drought tendencies and more extreme weather events, both of which are detrimental to agriculture. Increasing competition for water between agriculture and non-agricultural users also focuses attention on water management issues. Agriculture also has impact on the greenhouse gas balance. Forests and soils are natural sinks for CO2. Removal of forests and changes in land use, associated with the conversion from rural to urban domains, alters these natural sinks. Agricultural livestock and rice cultivation are leading contributors to methane emission into the atmosphere. The application of fertilizers is also a significant contributor to nitrous oxide emission into the atmosphere. Thus, efficient management strategies in agriculture can play an important role in managing the sources and sinks of greenhouse gases. Forest and land management can be effective tools in mitigating the greenhouse effect

  7. Research on the Natural Variability of Climate and the Impact of Anthropogenic Forcing on Climate

    Science.gov (United States)

    Stone, Peter H.

    2005-01-01

    The paper, "Latitude-dependent vertical mixing and the tropical thermocline in a global OGCM", was revised and published in Geophysical Research Letters. It treats the new GISS mixing scheme which includes the latitudinal dependence of the interior ocean turbulence field reported by Gregg, Sanford & Winkel. When implemented in the 3x3 degree NCAR CSMl OGCM [NCOMl] the new mixing scheme produces an improved, sharper equatorial thermoclines in both the Atlantic and the Pacific while simultaneously maintaining the realistic meridional overturning and northward heat transports found already with the previous GISS scheme. Also the paper "Diagnostics of the oceanic thermohaline circulation in a coupled climate model" describing earlier work on the grany was published.

  8. NDVI as a tool for measuring impact of climate variability upon vegetation

    Science.gov (United States)

    Delitala, Alessandro M. S.; Vizzari, Marco; Capece, Paolo; Fiori, Michele; Mannu, Giovanna Maria; Pacicco, Ciro Luca; Pinna Nossai, Roberto

    2010-05-01

    Land-atmosphere interactive processes are useful to understand impacts of year by year climate variability and to highlight possible trends, since the status of the natural vegetation cover is strongly controlled by climate factors. The so-called NDVI (Normalized Difference Vegetation Index), derived from the red and the near infrared channels of NOAA satellite, is a reliable indicator applicable to the analysis of photosynthetic biomass variations in vegetated areas. NDVI images, derived on a monthly basis by maximum composite value technique, can become a useful tool to monitor the dynamics of vegetation and to determine the maximum level of vegetation greenness observed over every year. Interannual variability of precipitation is likely to have a significant impact on the greenness of vegetation cover, since rainy seasons are expected to stimulate a much richer plants development than drier ones. The present poster intends to outline a research, jointly carried by ARPAS (the Regional Environmental Protection Agency of Sardinia) and the 'Department of Man and Territory' of the University of Perugia, that aimed to correlate the year by year variability of hydrological variables (precipitation and soil water content) and the maximum annual NDVI over the island of Sardinia. In order to do that, the authors defined four test areas, extending from 235 km2 to 1015 km2. Test areas were chosen in order to be mostly covered by natural vegetations, according to CORINE land-cover. Over such areas surface measures by ARPAS stations were compared against annual maximum NDVI index from 1998 to 2008, focusing on the so-called 'rainy season' that in Sardinia ranges from October to April. Precipitation for the selected areas was measured with the network of ground stations of ARPAS. Evapotranspiration was estimated by means of Hargreaves-Samani method applied to data from the above stations. Finally, estimation of the soil moisture content was carried out by means of a daily time

  9. Monitoring Crop Yield in USA Using a Satellite-Based Climate-Variability Impact Index

    Science.gov (United States)

    Zhang, Ping; Anderson, Bruce; Tan, Bin; Barlow, Mathew; Myneni, Ranga

    2011-01-01

    A quantitative index is applied to monitor crop growth and predict agricultural yield in continental USA. The Climate-Variability Impact Index (CVII), defined as the monthly contribution to overall anomalies in growth during a given year, is derived from 1-km MODIS Leaf Area Index. The growing-season integrated CVII can provide an estimate of the fractional change in overall growth during a given year. In turn these estimates can provide fine-scale and aggregated information on yield for various crops. Trained from historical records of crop production, a statistical model is used to produce crop yield during the growing season based upon the strong positive relationship between crop yield and the CVII. By examining the model prediction as a function of time, it is possible to determine when the in-season predictive capability plateaus and which months provide the greatest predictive capacity.

  10. Impacts of Climate Variability and Change on (Marine) Animals: Physiological Underpinnings and Evolutionary Consequences.

    Science.gov (United States)

    Pörtner, Hans O; Gutt, Julian

    2016-07-01

    variability throughout earth's history have influenced animal evolution and co-defined their success or failure from a bio-energetic point of view. Deepening such understanding may further reduce uncertainty about projected impacts of anthropogenic climate variability and change on the distribution, productivity and last not least, survival of aquatic and terrestrial species. PMID:27371560

  11. Hydrological Impacts of Land Use Change and Climate Variability in the Headwater Region of the Heihe River Basin, Northwest China

    Science.gov (United States)

    Zhang, Ling; Nan, Zhuotong; Xu, Yi; Li, Shuo

    2016-01-01

    Land use change and climate variability are two key factors impacting watershed hydrology, which is strongly related to the availability of water resources and the sustainability of local ecosystems. This study assessed separate and combined hydrological impacts of land use change and climate variability in the headwater region of a typical arid inland river basin, known as the Heihe River Basin, northwest China, in the recent past (1995–2014) and near future (2015–2024), by combining two land use models (i.e., Markov chain model and Dyna-CLUE) with a hydrological model (i.e., SWAT). The potential impacts in the near future were explored using projected land use patterns and hypothetical climate scenarios established on the basis of analyzing long-term climatic observations. Land use changes in the recent past are dominated by the expansion of grassland and a decrease in farmland; meanwhile the climate develops with a wetting and warming trend. Land use changes in this period induce slight reductions in surface runoff, groundwater discharge and streamflow whereas climate changes produce pronounced increases in them. The joint hydrological impacts are similar to those solely induced by climate changes. Spatially, both the effects of land use change and climate variability vary with the sub-basin. The influences of land use changes are more identifiable in some sub-basins, compared with the basin-wide impacts. In the near future, climate changes tend to affect the hydrological regimes much more prominently than land use changes, leading to significant increases in all hydrological components. Nevertheless, the role of land use change should not be overlooked, especially if the climate becomes drier in the future, as in this case it may magnify the hydrological responses. PMID:27348224

  12. Distinguishing the impacts of human activities and climate variability on runoff and sediment load change based on paired periods with similar weather conditions

    NARCIS (Netherlands)

    Wang, Fei; Hessel, Rudi; Mu, Xingmin; Maroulis, Jerry; Zhao, Guangju; Geissen, Violette; Ritsema, Coen

    2015-01-01

    Runoff and sediment loads from river basin are largely affected by the interplay of climate variability and human activities within the basin. However, distinguishing the impacts of climate variability and human activities would vastly improve our knowledge of water resources, climate variability

  13. Climate variability and human impact in South America during the last 2000 years: synthesis and perspectives from pollen records

    Science.gov (United States)

    Flantua, S. G. A.; Hooghiemstra, H.; Vuille, M.; Behling, H.; Carson, J. F.; Gosling, W. D.; Hoyos, I.; Ledru, M. P.; Montoya, E.; Mayle, F.; Maldonado, A.; Rull, V.; Tonello, M. S.; Whitney, B. S.; González-Arango, C.

    2016-02-01

    An improved understanding of present-day climate variability and change relies on high-quality data sets from the past 2 millennia. Global efforts to model regional climate modes are in the process of being validated against, and integrated with, records of past vegetation change. For South America, however, the full potential of vegetation records for evaluating and improving climate models has hitherto not been sufficiently acknowledged due to an absence of information on the spatial and temporal coverage of study sites. This paper therefore serves as a guide to high-quality pollen records that capture environmental variability during the last 2 millennia. We identify 60 vegetation (pollen) records from across South America which satisfy geochronological requirements set out for climate modelling, and we discuss their sensitivity to the spatial signature of climate modes throughout the continent. Diverse patterns of vegetation response to climate change are observed, with more similar patterns of change in the lowlands and varying intensity and direction of responses in the highlands. Pollen records display local-scale responses to climate modes; thus, it is necessary to understand how vegetation-climate interactions might diverge under variable settings. We provide a qualitative translation from pollen metrics to climate variables. Additionally, pollen is an excellent indicator of human impact through time. We discuss evidence for human land use in pollen records and provide an overview considered useful for archaeological hypothesis testing and important in distinguishing natural from anthropogenically driven vegetation change. We stress the need for the palynological community to be more familiar with climate variability patterns to correctly attribute the potential causes of observed vegetation dynamics. This manuscript forms part of the wider LOng-Term multi-proxy climate REconstructions and Dynamics in South America - 2k initiative that provides the ideal

  14. Revealing The Impact Of Climate Variability On The Wind Resource Using Data Mining Techniques

    Science.gov (United States)

    Clifton, A.; Lundquist, J. K.

    2011-12-01

    Wind turbines harvest energy from the wind. Winds at heights where industrial-scale turbines operate, up to 200 m above ground, experience a complex interaction between the atmosphere and the Earth's surface. Previous studies for a variety of locations have shown that the wind resource varies over time. In some locations, this variability can be related to large-scale climate oscillations as revealed in climate indices such as the El-Nino-Southern Oscillation (ENSO). These indices can be used to quantify climate change in the past, and can also be extracted from models of future climate. Understanding the correlation between climate indices and wind resources therefore allows us to understand how climate change may influence wind energy production. We present a new methodology for assessing relevant climate modes of oscillation at a given site in order to quantify future wind resource variability. We demonstrate the method on a 14-year record of 10-minute averaged wind speed and wind direction data from several levels of an 80m tower at the National Renewable Energy Laboratory (NREL) National Wind Technology Center near Boulder, Colorado. Data mining techniques (based on k-means clustering) identify 4 major groups of wind speed and direction. After removing annual means, each cluster was compared to a series of climate indices, including the Arctic Oscillation (AO) and Multivariate ENSO Index (MEI). Statistically significant relationships emerge between individual clusters and climate indices. At this location, this result is consistent with the MEI's relationship with other meteorological parameters, such as precipitation, in the Rocky Mountain Region. The presentation will illustrate these relationships between wind resource at this location and other relevant climate indices, and suggest how these relationships can provide a foundation for quantifying the potential future variability of wind energy production at this site and others.

  15. Recent variability of the solar spectral irradiance and its impact on climate modelling

    Directory of Open Access Journals (Sweden)

    I. Ermolli

    2013-04-01

    Full Text Available The lack of long and reliable time series of solar spectral irradiance (SSI measurements makes an accurate quantification of solar contributions to recent climate change difficult. Whereas earlier SSI observations and models provided a qualitatively consistent picture of the SSI variability, recent measurements by the SORCE (SOlar Radiation and Climate Experiment satellite suggest a significantly stronger variability in the ultraviolet (UV spectral range and changes in the visible and near-infrared (NIR bands in anti-phase with the solar cycle. A number of recent chemistry-climate model (CCM simulations have shown that this might have significant implications on the Earth's atmosphere. Motivated by these results, we summarize here our current knowledge of SSI variability and its impact on Earth's climate. We present a detailed overview of existing SSI measurements and provide thorough comparison of models available to date. SSI changes influence the Earth's atmosphere, both directly, through changes in shortwave (SW heating and therefore, temperature and ozone distributions in the stratosphere, and indirectly, through dynamical feedbacks. We investigate these direct and indirect effects using several state-of-the art CCM simulations forced with measured and modelled SSI changes. A unique asset of this study is the use of a common comprehensive approach for an issue that is usually addressed separately by different communities. We show that the SORCE measurements are difficult to reconcile with earlier observations and with SSI models. Of the five SSI models discussed here, specifically NRLSSI (Naval Research Laboratory Solar Spectral Irradiance, SATIRE-S (Spectral And Total Irradiance REconstructions for the Satellite era, COSI (COde for Solar Irradiance, SRPM (Solar Radiation Physical Modelling, and OAR (Osservatorio Astronomico di Roma, only one shows a behaviour of the UV and visible irradiance qualitatively resembling that of the recent

  16. Impacts of climate variability and extreme events on the terrestrial carbon cycle of the Amazon basin

    Science.gov (United States)

    Harper, A. B.; Cox, P.; Wiltshire, A.; Friedlingstein, P.; Jones, C. D.; Mercado, L.; Groenendijk, M.; Sitch, S.

    2013-12-01

    , biomass, and photosynthesis. Simulated fluxes of net ecosystem exchange, sensible and latent heat fluxes were closest to FLUXNET observations when the model was run with optimized physiological parameters, deep roots, and a relaxed soil moisture stress function. We also compared seasonality of modelled photosynthesis to that implied from measurements of sun-induced chlorophyll fluorescence from the GOSAT satellite, and found good agreement. This gives us confidence in using the model to assess impacts of climate variability. Over the past several decades, the largest fluxes of CO2 from the biosphere to the atmosphere occurred during years of extreme drought: for example during 1987, 1998, and 2010. We analyse the driving factors behind these fluxes to assess climate sensitivity of the Amazon rainforest. The relationship between terrestrial carbon fluxes and sea surface temperatures in the Atlantic and Pacific Oceans are explored as the largest source of the variability, which can help in predicting future sensitivity of the forest.

  17. Ocean impact on decadal Atlantic climate variability revealed by sea-level observations

    OpenAIRE

    McCarthy, Gerard D.; Haigh, Ivan D.; Hirschi, Joël J.-M.; Grist, Jeremy P.; Smeed, David A.

    2015-01-01

    Decadal variability is a notable feature of the Atlantic Ocean and the climate of the regions it influences. Prominently, this is manifested in the Atlantic Multidecadal Oscillation (AMO) in sea surface temperatures. Positive (negative) phases of the AMO coincide with warmer (colder) North Atlantic sea surface temperatures. The AMO is linked with decadal climate fluctuations, such as Indian and Sahel rainfall1, European summer precipitation2, Atlantic hurricanes3 and variations in global temp...

  18. The health impacts of climate change and variability in developing countries

    Energy Technology Data Exchange (ETDEWEB)

    Menne, B. [WHO European Centre for Environment and Health, Rome (Italy). Global Change and Health; Kunzil, N. [Institute for Social and Preventive Medicine University, Los Angeles, CA (United States). Basel and Keck School of Medicine; Bertollini, R. [WHO Regional Office for Europe, Copenhagen (Denmark). Technical Support Div.

    2002-07-01

    Health is a focus reflecting the combined impacts of climate change on the physical environment, ecosystems, the economic environment and society. Long-term changes in the world's climate may affect many requisites of good health - sufficient food, safe and adequate drinking water and secure dwelling. The current large-scale social and environmental changes mean that we must assign a much higher priority to population health in the policy debate on climate change. Climate change will affect human health and wellbeing through a variety of mechanisms. Climate change can adversely impact on the availability of fresh water supply and the efficiency of local sewerage systems. It is also likely to affect food security. Cereal yields are expected to increase at high and mid latitudes but decrease at lower latitudes. Changes in food production are likely to significantly affect health in Africa. In addition, the distribution and seasonal transmission of several vector-borne infectious diseases (such as malaria and dengue) may be affected by climate change. Altered distribution of some vector species may be among the early signals of climate change. A change in the world climate could increase the frequency and severity of extreme weather events. The impacts on health of natural disasters are considerable - the number of people killed, injured or made homeless from such causes is increasingly alarming. The vulnerability of people living in risk-prone areas is an important contributor to disaster casualties and damage. An increase in heatwaves (and possibly air pollution) will be a problem in urban areas, where excess mortality and morbidity is currently observed during hot weather episodes. We can assume that climate change will affect the most vulnerable in developing countries. These might be socio-economic deprived populations, people who lack access to a health care system, technology and communication, as well as immuno compromised persons. The health community

  19. NPOESS, Essential Climates Variables and Climate Change

    Science.gov (United States)

    Forsythe-Newell, S. P.; Bates, J. J.; Barkstrom, B. R.; Privette, J. L.; Kearns, E. J.

    2008-12-01

    Advancement in understanding, predicting and mitigating against climate change implies collaboration, close monitoring of Essential Climate Variable (ECV)s through development of Climate Data Record (CDR)s and effective action with specific thematic focus on human and environmental impacts. Towards this end, NCDC's Scientific Data Stewardship (SDS) Program Office developed Climate Long-term Information and Observation system (CLIO) for satellite data identification, characterization and use interrogation. This "proof-of-concept" online tool provides the ability to visualize global CDR information gaps and overlaps with options to temporally zoom-in from satellite instruments to climate products, data sets, data set versions and files. CLIO provides an intuitive one-stop web site that displays past, current and planned launches of environmental satellites in conjunction with associated imagery and detailed information. This tool is also capable of accepting and displaying Web-based input from Subject Matter Expert (SME)s providing a global to sub-regional scale perspective of all ECV's and their impacts upon climate studies. SME's can access and interact with temporal data from the past and present, or for future planning of products, datasets/dataset versions, instruments, platforms and networks. CLIO offers quantifiable prioritization of ECV/CDR impacts that effectively deal with climate change issues, their associated impacts upon climate, and this offers an intuitively objective collaboration and consensus building tool. NCDC's latest tool empowers decision makers and the scientific community to rapidly identify weaknesses and strengths in climate change monitoring strategies and significantly enhances climate change collaboration and awareness.

  20. Impact of climatic change on ocean carbon fluxes. Role of the decadal variability

    International Nuclear Information System (INIS)

    Since the industrial revolution, oceans have absorbed roughly one quarter of the anthropogenic emissions of CO2, slowing down climate change. The evolution of the ocean carbon sink, paralleled to the anthropogenic CO2 emissions, is ruled by the CO2 as well as climate. Influence of atmospheric CO2 in the recent evolution of the ocean carbon sink is well understood whilst this is not the case for the climate's one. Indeed, some authors claim that the recent variations of the ocean CO2 sink can be attributed to climate change, whereas some others suggest that these latter are controlled by a decadal variability, which is poorly understood. In this thesis, we address question relative to the role of the decadal variability of the ocean carbon fluxes through the mean of numerical modeling. On one hand, we have demonstrated that ocean carbon fluxes exhibit decadal fluctuations within the high latitudes oceans. These fluctuations displays modes of 10 to 50-year long which account for 20 to 40% of the year-to-year variability. Thanks to Detection and Attribution methods applied to RECCAP project's reconstructions (1960-2005), we have then assessed whether the occurrence of fluctuations at decadal time scale could hamper the detection of the climate contribution to the recent evolution of ocean carbon fluxes. We have shown that the climate contribution is indeed not detected in the high latitude oceans due to the presence of decadal mode of variability. In the low latitude oceans instead, the weaker fluctuations of ocean carbon fluxes at decadal time scale favor the detection of climate influence in the recent variations of the CO2 fluxes. (author)

  1. Temporal Structures of the North Atlantic Oscillation and Its Impact on the Regional Climate Variability

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    In this study, the temporal structure of the variation of North Atlantic Oscillation (NAO) and its impact on regional climate variability are analyzed using various datasets. The results show that blocking formations in the Atlantic region are sensitive to the phase of the NAO. Sixty-seven percent more winter blocking days are observed during the negative phase compared to the positive phase of the NAO. The average length of blocking during the negative phase is about 11 days, which is nearly twice as long as the 6-day length observed during the positive phase of the NAO. The NAO-related differences in blocking frequency and persistence are associated with changes in the distribution of the surface air temperature anomaly, which, to a large extent, is determined by the phase of the NAO. The distribution of regional cloud amount is also sensitive to the phase of the NAO. For the negative phase, the cloud amounts are significant, positive anomalies in the convective zone in the Tropics and much less cloudiness in the mid latitudes. But for the positive phase of the NAO, the cloud amount is much higher in the mid-latitude storm track region. In the whole Atlantic region, the cloud amount shows a decrease with the increase of surface air temperature. These results suggest that there may be a negative feedback between the cloud amount and the surface air temperature in the Atlantic region.

  2. Climate Variability and Its Impact on Forest Hydrology on South Carolina Coastal Plain, USA

    Directory of Open Access Journals (Sweden)

    Carl C. Trettin

    2011-08-01

    Full Text Available Understanding the changes in hydrology of coastal forested wetlands induced by climate change is fundamental for developing strategies to sustain their functions and services. This study examined 60 years of climatic observations and 30 years of hydrological data, collected at the Santee Experimental Forest (SEF in coastal South Carolina. We also applied a physically-based, distributed hydrological model (MIKE SHE to better understand the hydrological responses to the observed climate variability. The results from both observation and simulation for the paired forested watershed systems indicated that the forest hydrology was highly susceptible to change due to climate change. The stream flow and water table depth was substantially altered with a change in precipitation. Both flow and water table level decreased with a rise in temperature. The results also showed that hurricanes substantially influenced the forest hydrological patterns for a short time period (several years as a result of forest damage.

  3. Climate variability and human impact on the environment in South America during the last 2000 years: synthesis and perspectives

    Science.gov (United States)

    Flantua, S. G. A.; Hooghiemstra, H.; Vuille, M.; Behling, H.; Carson, J. F.; Gosling, W. D.; Hoyos, I.; Ledru, M. P.; Montoya, E.; Mayle, F.; Maldonado, A.; Rull, V.; Tonello, M. S.; Whitney, B. S.; González-Arango, C.

    2015-07-01

    An improved understanding of present-day climate variability and change relies on high-quality data sets from the past two millennia. Global efforts to reconstruct regional climate modes are in the process of validating and integrating paleo-proxies. For South America, however, the full potential of vegetation records for evaluating and improving climate models has hitherto not been sufficiently acknowledged due to its unknown spatial and temporal coverage. This paper therefore serves as a guide to high-quality pollen records that capture environmental variability during the last two millennia. We identify the pollen records with the required temporal characteristics for PAGES-2 ka climate modelling and we discuss their sensitivity to the spatial signature of climate modes throughout the continent. Diverse patterns of vegetation response to climate change are observed, with more similar patterns of change in the lowlands and varying intensity and direction of responses in the highlands. Pollen records display local scale responses to climate modes, thus it is necessary to understand how vegetation-climate interactions might diverge under variable settings. Additionally, pollen is an excellent indicator of human impact through time. Evidence for human land use in pollen records is useful for archaeological hypothesis testing and important in distinguishing natural from anthropogenically driven vegetation change. We stress the need for the palynological community to be more familiar with climate variability patterns to correctly attribute the potential causes of observed vegetation dynamics. The LOTRED-SA-2 k initiative provides the ideal framework for the integration of the various paleoclimatic sub-disciplines and paleo-science, thereby jumpstarting and fostering multi-disciplinary research into environmental change on centennial and millennial time scales.

  4. Climate variability and human impact on the environment in South America during the last 2000 years: synthesis and perspectives

    Directory of Open Access Journals (Sweden)

    S. G. A. Flantua

    2015-07-01

    Full Text Available An improved understanding of present-day climate variability and change relies on high-quality data sets from the past two millennia. Global efforts to reconstruct regional climate modes are in the process of validating and integrating paleo-proxies. For South America, however, the full potential of vegetation records for evaluating and improving climate models has hitherto not been sufficiently acknowledged due to its unknown spatial and temporal coverage. This paper therefore serves as a guide to high-quality pollen records that capture environmental variability during the last two millennia. We identify the pollen records with the required temporal characteristics for PAGES-2 ka climate modelling and we discuss their sensitivity to the spatial signature of climate modes throughout the continent. Diverse patterns of vegetation response to climate change are observed, with more similar patterns of change in the lowlands and varying intensity and direction of responses in the highlands. Pollen records display local scale responses to climate modes, thus it is necessary to understand how vegetation-climate interactions might diverge under variable settings. Additionally, pollen is an excellent indicator of human impact through time. Evidence for human land use in pollen records is useful for archaeological hypothesis testing and important in distinguishing natural from anthropogenically driven vegetation change. We stress the need for the palynological community to be more familiar with climate variability patterns to correctly attribute the potential causes of observed vegetation dynamics. The LOTRED-SA-2 k initiative provides the ideal framework for the integration of the various paleoclimatic sub-disciplines and paleo-science, thereby jumpstarting and fostering multi-disciplinary research into environmental change on centennial and millennial time scales.

  5. From water to bioethanol: The impact of climate variability on the water footprint

    Science.gov (United States)

    Dalla Marta, Anna; Mancini, Marco; Natali, Francesca; Orlando, Francesca; Orlandini, Simone

    2012-06-01

    SummaryDuring recent years, the opportunity to use energy crops for the production of biofuels aroused many interest by virtue of the potential reduction of green house gasses emissions associated to their large-scale use. Nevertheless, many studies highlight that the substitution of fossil fuels with biofuels from energy crops can lead up to serious problems related to the pressure on water resources. The present research had the aim to investigate the relations existing between biofuels production and the pressure on water resources, and how these relations are affected by climate variability. To this aim, the water footprint of maize cultivation in Tuscany (central Italy) was computed and its trend was analyzed during the last 55 years in relation to climate variability with particular attention to precipitations. The results demonstrated that the WF was affected by climate variability mainly through the effect of climate on the crop cycle. The total WF decreased over time but an increase of the blue component was found due to the change in precipitation patterns and to the rise of temperatures. Concerning the gray WF, despite a decrease in the last 55-years period mainly due to precipitation decrease, there was a reduction in N uptake by the crop and an accumulation of nitrate into the soil.

  6. Impact of climate variability on runoff in the north-central United States

    Science.gov (United States)

    Ryberg, Karen R.; Lin, Wei; Vecchia, Aldo V.

    2014-01-01

    Large changes in runoff in the north-central United States have occurred during the past century, with larger floods and increases in runoff tending to occur from the 1970s to the present. The attribution of these changes is a subject of much interest. Long-term precipitation, temperature, and streamflow records were used to compare changes in precipitation and potential evapotranspiration (PET) to changes in runoff within 25 stream basins. The basins studied were organized into four groups, each one representing basins similar in topography, climate, and historic patterns of runoff. Precipitation, PET, and runoff data were adjusted for near-decadal scale variability to examine longer-term changes. A nonlinear water-balance analysis shows that changes in precipitation and PET explain the majority of multidecadal spatial/temporal variability of runoff and flood magnitudes, with precipitation being the dominant driver. Historical changes in climate and runoff in the region appear to be more consistent with complex transient shifts in seasonal climatic conditions than with gradual climate change. A portion of the unexplained variability likely stems from land-use change.

  7. Timing of climate variability and grassland productivity

    OpenAIRE

    Craine, Joseph M.; Nippert, Jesse B.; Andrew J Elmore; Skibbe, Adam M.; Hutchinson, Stacy L.; Brunsell, Nathaniel A.

    2012-01-01

    Future climates are forecast to include greater precipitation variability and more frequent heat waves, but the degree to which the timing of climate variability impacts ecosystems is uncertain. In a temperate, humid grassland, we examined the seasonal impacts of climate variability on 27 y of grass productivity. Drought and high-intensity precipitation reduced grass productivity only during a 110-d period, whereas high temperatures reduced productivity only during 25 d in July. The effects o...

  8. Impact of climate variability and anthropogenic activity on streamflow in the Three Rivers Headwater Region, Tibetan Plateau, China

    Science.gov (United States)

    Jiang, Chong; Li, Daiqing; Gao, Yanni; Liu, Wenfeng; Zhang, Linbo

    2016-05-01

    Under the impacts of climate variability and human activities, there is violent fluctuation for streamflow in the large basins in China. Therefore, it is crucial to separate the impacts of climate variability and human activities on streamflow fluctuation for better water resources planning and management. In this study, the Three Rivers Headwater Region (TRHR) was chosen as the study area. Long-term hydrological data for the TRHR were collected in order to investigate the changes in annual runoff during the period of 1956-2012. The nonparametric Mann-Kendall test, moving t test, Pettitt test, Mann-Kendall-Sneyers test, and the cumulative anomaly curve were used to identify trends and change points in the hydro-meteorological variables. Change point in runoff was identified in the three basins, which respectively occurred around the years 1989 and 1993, dividing the long-term runoff series into a natural period and a human-induced period. Then, the hydrologic sensitivity analysis method was employed to evaluate the effects of climate variability and human activities on mean annual runoff for the human-induced period based on precipitation and potential evapotranspiration. In the human-induced period, climate variability was the main factor that increased (reduced) runoff in LRB and YARB (YRB) with contribution of more than 90 %, while the increasing (decreasing) percentage due to human activities only accounted for less than 10 %, showing that runoff in the TRHR is more sensitive to climate variability than human activities. The intra-annual distribution of runoff shifted gradually from a double peak pattern to a single peak pattern, which was mainly influenced by atmospheric circulation in the summer and autumn. The inter-annual variation in runoff was jointly controlled by the East Asian monsoon, the westerly, and Tibetan Plateau monsoons.

  9. Impacts of Multi-Scale Solar Activity on Climate.Part Ⅱ: Dominant Timescales in Decadal-Centennial Climate Variability

    Institute of Scientific and Technical Information of China (English)

    Hengyi WENG

    2012-01-01

    Part Ⅱ of this study detects the dominant decadal-centennial timescales in four SST indices up to the 2010/2011 winter and tries to relate them to the observed 11-yr and 88-yr solar activity with the sunspot number up to Solar Cycle 24.To explore plausible solar origins of the observed decadal-centennial timescales in the SSTs and climate variability in general,we design a simple one-dimensional dynamical system forced by an annual cycle modulated by a small-amplitude single- or multi-scale “solar activity.” Results suggest that nonlinear harmonic and subharmonic resonance of the system to the forcing and period-doubling bifurcations are responsible for the dominant timescales in the system,including the 60-yr timescale that dominates the Atlantic Multidecadal Oscillation.The dominant timescales in the forced system depend on the system's parameter setting.Scale enhancement among the dominant response timescales may result in dramatic amplifications over a few decades and extreme values of the time series on various timescales.Three possible energy sources for such amplifications and extremes are proposed.Dynamical model results suggest that solar activity may play an important yet not well recognized role in the observed decadal-centennial climate variability.The atmospheric dynamical amplifying mechanism shown in Part Ⅰ and the nonlinear resonant and bifurcation mechanisms shown in Part Ⅱ help us to understand the solar source of the multi-scale climate change in the 20th century and the fact that different solar influenced dominant timescales for recurrent climate extremes for a given region or a parameter setting.Part Ⅱ also indicates that solar influences on climate cannot be linearly compared with non-cyclic or sporadic thermal forcings because they cannot exert their influences on climate in the same way as the sun does.

  10. Climate Variability Program

    Science.gov (United States)

    Halpern, David (Editor)

    2002-01-01

    The Annual Report of the Climate Variability Program briefly describes research activities of Principal Investigators who are funded by NASA's Earth Science Enterprise Research Division. The report is focused on the year 2001. Utilization of satellite observations is a singularity of research on climate science and technology at JPL (Jet Propulsion Laboratory). Research at JPL has two foci: generate new knowledge and develop new technology.

  11. An analysis of the impacts of climatic variability and hydrology on the coastal fisheries, Engraulis encrasicolus and Sepia officinalis, of Portugal

    OpenAIRE

    Ullah, Hadayet; Leitao, F.; Baptista, Vânia; Chícharo, Luís

    2012-01-01

    The notion that climate change may impact coastal fish production suggests a need to understand how climatic variables may influence fish catches at different time scales. Evidence suggests that the effect of climatic variability and fishing effort on landed catches (as proxy of fish abundance) may vary at the regional scale. This study aims to assess the sensibility of two commercial species with a short life cycle (Engraulis encrasicolus and Sepia officinalis) to climatic and fisheries effe...

  12. Potential impacts of climate variability on dengue hemorrhagic fever in Honduras, 2010.

    Science.gov (United States)

    Zambrano, L I; Sevilla, C; Reyes-García, S Z; Sierra, M; Kafati, R; Rodriguez-Morales, A J; Mattar, S

    2012-12-01

    Climate change and variability are affecting human health and disease direct or indirectly through many mechanisms. Dengue is one of those diseases that is strongly influenced by climate variability; however its study in Central America has been poorly approached. In this study, we assessed potential associations between macroclimatic and microclimatic variation and dengue hemorrhagic fever (DHF) cases in the main hospital of Honduras during 2010. In this year, 3,353 cases of DHF were reported in the Hospital Escuela, Tegucigalpa. Climatic periods marked a difference of 158% in the mean incidence of cases, from El Niño weeks (-99% of cases below the mean incidence) to La Niña months (+59% of cases above it) (p<0.01). Linear regression showed significantly higher dengue incidence with lower values of Oceanic Niño Index (p=0.0097), higher rain probability (p=0.0149), accumulated rain (p=0.0443) and higher relative humidity (p=0.0292). At a multiple linear regression model using those variables, ONI values shown to be the most important and significant factor found to be associated with the monthly occurrence of DHF cases (r²=0.649; βstandardized=-0.836; p=0.01). As has been shown herein, climate variability is an important element influencing the dengue epidemiology in Honduras. However, it is necessary to extend these studies in this and other countries in the Central America region, because these models can be applied for surveillance as well as for prediction of dengue. PMID:23202593

  13. Assessing potential impacts of climate change and variability on the Great Lakes-St. Lawrence Basin: A binational approach

    International Nuclear Information System (INIS)

    The potential impacts of climate change and variability on the Great Lakes environment are serious and complex. The Great Lakes-St. Lawrence Basin is home to 42.5 million US and Canadian citizens and is the industrial and commercial heartland of both nations. The region is rich in human and natural resources, with diverse economic activities and substantial infrastructure which would be affected by major shifts in climate. For example, water level changes could affect wetland distribution and functioning; reductions in streamflow would alter assimilative capacities while warmer water temperatures would influence spring and fall turnover and incidence of anoxia. A binational program has been initiated to conduct interdisciplinary, integrated impact assessments for the Great Lakes-St. Lawrence River Basin. The goal of this program is to undertake interdisciplinary, integrated studies to improve the understanding of the complex interactions between climate, the environment, and socioeconomic systems in order to develop informed regional adaptation responses

  14. Climate change impact on the roles of temperature and precipitation in western U.S. snowpack variability

    Science.gov (United States)

    Scalzitti, Jason; Strong, Courtenay; Kochanski, Adam

    2016-05-01

    We employ dynamical downscaling and pseudo global warming methodologies to evaluate climate change impact on the roles of temperature and precipitation in spring snowpack (S) variability across the western United States (U.S.). The negative correlation between S and temperature weakens linearly with elevation, whereas the correlation between S and precipitation increases asymptotically with elevation. The curvilinear relationship in the latter case was not visible in prior studies because of the observation networks' limited range. In our historical validation, there is a range of threshold elevations (1580-2181 m) across six mountainous regions, above which precipitation is the main driver of snowpack variability and below which temperature is the main driver. Under a moderate end-of-century climate change scenario, these thresholds increase by 191 to 432 m. These rising thresholds indicate increasing spatial and elevational vulnerability of western U.S. spring snowpack along with associated impacts to hydrologic and ecologic systems.

  15. A modelling framework to project future climate change impacts on streamflow variability and extremes in the West River, China

    Science.gov (United States)

    Fei, Y.; Yeou-Koung, T.; Liliang, R.

    2014-09-01

    In this study, a hydrological modelling framework was introduced to assess the climate change impacts on future river flow in the West River basin, China, especially on streamflow variability and extremes. The modelling framework includes a delta-change method with the quantile-mapping technique to construct future climate forcings on the basis of observed meteorological data and the downscaled climate model outputs. This method is able to retain the signals of extreme weather events, as projected by climate models, in the constructed future forcing scenarios. Fed with the historical and future forcing data, a large-scale hydrologic model (the Variable Infiltration Capacity model, VIC) was executed for streamflow simulations and projections at daily time scales. A bootstrapping resample approach was used as an indirect alternative to test the equality of means, standard deviations and the coefficients of variation for the baseline and future streamflow time series, and to assess the future changes in flood return levels. The West River basin case study confirms that the introduced modelling framework is an efficient effective tool to quantify streamflow variability and extremes in response to future climate change.

  16. Changing mechanism of global water scarcity events: Impacts of socioeconomic changes and inter-annual hydro-climatic variability

    OpenAIRE

    Veldkamp, T.I.E.; Wada, Y.; Moel, de, H.; Kummu, M.S.; Eisner, S.; J. C. J. H. Aerts; Ward, P J

    2015-01-01

    79%) of the yearly changes in global water scarcity, whilst only after six to ten years, socioeconomic developments become the largest driver of change. Moreover, our results showed that the growth in the relative contribution of socioeconomic developments to changing water scarcity conditions stabilizes towards 2000 and that the impacts of hydro-climatic variability remain significantly important. The findings presented in this paper could be of use for water managers and policy makers copin...

  17. Climate variability and change

    International Nuclear Information System (INIS)

    When Australia's climate should not be definite barrier to the population reaching 30 million by 2050, it is recognised that our climate has limited the development of the nation over the past 200 years. Indeed in 1911, based on a comparison of the climate and development between the US and Australia. Griffith Taylor predicted that Australia's population would be 19 million at the end of the 20th century, which is a pretty good 90-year forecast. The climate constraint is not only due to much of the country being semi-arid with an annual rainfall below 400 millimetres, but also due to the large year-to-year variability of rainfall across the country

  18. Current Climate Variability & Change

    Science.gov (United States)

    Diem, J.; Criswell, B.; Elliott, W. C.

    2013-12-01

    Current Climate Variability & Change is the ninth among a suite of ten interconnected, sequential labs that address all 39 climate-literacy concepts in the U.S. Global Change Research Program's Climate Literacy: The Essential Principles of Climate Sciences. The labs are as follows: Solar Radiation & Seasons, Stratospheric Ozone, The Troposphere, The Carbon Cycle, Global Surface Temperature, Glacial-Interglacial Cycles, Temperature Changes over the Past Millennium, Climates & Ecosystems, Current Climate Variability & Change, and Future Climate Change. All are inquiry-based, on-line products designed in a way that enables students to construct their own knowledge of a topic. Questions representative of various levels of Webb's depth of knowledge are embedded in each lab. In addition to the embedded questions, each lab has three or four essential questions related to the driving questions for the lab suite. These essential questions are presented as statements at the beginning of the material to represent the lab objectives, and then are asked at the end as questions to function as a summative assessment. For example, the Current Climate Variability & Change is built around these essential questions: (1) What has happened to the global temperature at the Earth's surface, in the middle troposphere, and in the lower stratosphere over the past several decades?; (2) What is the most likely cause of the changes in global temperature over the past several decades and what evidence is there that this is the cause?; and (3) What have been some of the clearly defined effects of the change in global temperature on the atmosphere and other spheres of the Earth system? An introductory Prezi allows the instructor to assess students' prior knowledge in relation to these questions, while also providing 'hooks' to pique their interest related to the topic. The lab begins by presenting examples of and key differences between climate variability (e.g., Mt. Pinatubo eruption) and

  19. Assessment of climate change impacts on rainfall using large scale climate variables and downscaling models – A case study

    Indian Academy of Sciences (India)

    Azadeh Ahmadi; Ali Moridi; Elham Kakaei Lafdani; Ghasem Kianpisheh

    2014-10-01

    Many of the applied techniques in water resources management can be directly or indirectly influenced by hydro-climatology predictions. In recent decades, utilizing the large scale climate variables as predictors of hydrological phenomena and downscaling numerical weather ensemble forecasts has revolutionized the long-lead predictions. In this study, two types of rainfall prediction models are developed to predict the rainfall of the Zayandehrood dam basin located in the central part of Iran. The first seasonal model is based on large scale climate signals data around the world. In order to determine the inputs of the seasonal rainfall prediction model, the correlation coefficient analysis and the new Gamma Test (GT) method are utilized. Comparison of modelling results shows that the Gamma test method improves the Nash–Sutcliffe efficiency coefficient of modelling performance as 8% and 10% for dry and wet seasons, respectively. In this study, Support Vector Machine (SVM) model for predicting rainfall in the region has been used and its results are compared with the benchmark models such as K-nearest neighbours (KNN) and Artificial Neural Network (ANN). The results show better performance of the SVM model at testing stage. In the second model, statistical downscaling model (SDSM) as a popular downscaling tool has been used. In this model, using the outputs from GCM, the rainfall of Zayandehrood dam is projected under two climate change scenarios. Most effective variables have been identified among 26 predictor variables. Comparison of the results of the two models shows that the developed SVM model has lesser errors in monthly rainfall estimation. The results show that the rainfall in the future wet periods are more than historical values and it is lower than historical values in the dry periods. The highest monthly uncertainty of future rainfall occurs in March and the lowest in July.

  20. Potential impacts of a future Grand Solar Minimum on decadal regional climate change and interannual hemispherical climate variability

    Science.gov (United States)

    Spiegl, Tobias; Langematz, Ulrike

    2016-04-01

    The political, technical and socio-economic developments of the next decades will determine the magnitude of 21st century climate change, since they are inextricably linked to future anthropogenic greenhouse gas emissions. To assess the range of uncertainty that is related to these developments, it is common to assume different emission scenarios for 21st climate projections. While the uncertainties associated with the anthropogenic greenhouse gas forcing have been studied intensely, the contribution of natural climate drivers (particularly solar variability) to recent and future climate change are subject of intense debate. The past 1,000 years featured at least 5 excursions (lasting 60-100 years) of exceptionally low solar activity, induced by a weak magnetic field of the Sun, so called Grand Solar Minima. While the global temperature response to such a decrease in solar activity is assumed to be rather small, nonlinear mechanisms in the climate system might amplify the regional temperature signal. This hypothesis is supported by the last Grand Solar Minimum (the Maunder Minimum, 1645-1715) which coincides with the Little Ice Age, an epoch which is characterized by severe cold and hardship over Europe, North America and Asia. The long-lasting minimum of Solar Cycle 23 as well as the overall weak maximum of Cycle 24 reveal the possibility for a return to Grand Solar Minimum conditions within the next decades. The quantification of the implications of such a projected decrease in solar forcing is of ultimate importance, given the on-going public discussion of the role of carbon dioxide emissions for global warming, and the possible role a cooling due to decreasing solar activity could be ascribed to. Since there is still no clear consensus about the actual strength of the Maunder Minimum, we used 3 acknowledged solar reconstruction datasets that show significant differences in both, total solar irradiance (TSI) and spectral irradiance (SSI) to simulate a future

  1. Impact of climate variability on N and C flux within the life cycle of biofuels produced from crop residues

    Science.gov (United States)

    Pourhashem, G.; Block, P. J.; Adler, P. R.; Spatari, S.

    2013-12-01

    Biofuels from agricultural feedstocks (lignocellulose) are under development to meet national policy objectives for producing domestic renewable fuels. Using crop residues such as corn stover as feedstock for biofuel production can minimize the risks associated with food market disruption; however, it demands managing residue removal to minimize soil carbon loss, erosion, and to ensure nutrient replacement. Emissions of nitrous oxide and changes to soil organic carbon (SOC) are subject to variability in time due to local climate conditions and cultivation practices. Our objective is to investigate the effect of climate inputs (precipitation and temperature) on biogeochemical greenhouse gas (GHG) emissions (N2O and SOC expressed as CO2) within the life cycle of biofuels produced from agricultural residues. Specifically, we investigate the impact of local climate variability on soil carbon and nitrogen fluxes over a 20-year biorefinery lifetime where biomass residue is used for lignocellulosic ethanol production. We investigate two cases studied previously (Pourhashem et al, 2013) where the fermentable sugars in the agricultural residue are converted to ethanol (biofuel) and the lignin byproduct is used in one of two ways: 1) power co-generation; or 2) application to land as a carbon/nutrient-rich amendment to soil. In the second case SOC losses are mitigated through returning the lignin component to land while the need for fertilizer addition is also eliminated, however in both cases N2O and SOC are subject to variability due to variable climate conditions. We used the biogeochemical model DayCent to predict soil carbon and nitrogen fluxes considering soil characteristics, tillage practices and local climate (e.g. temperature and rainfall). We address the impact of climate variability on the soil carbon and nitrogen fluxes by implementing a statistical bootstrap resampling method based on a historic data set (1980 to 2000). The ensuing probabilistic outputs from the

  2. Impacts of Climate Variability on Non-native Plant Invasion in the Western U.S.

    Science.gov (United States)

    Bradley, B. A.

    2006-12-01

    Plant invasions are changing ecosystem structure and function throughout the United States. In many areas of the west, invasive species such as tamarisk (Tamarix spp.), cheatgrass (Bromus tectorum), and yellow starthistle (Centaurea solstitialis) dominate landscapes. Expansion of these species is occurring at a staggering rate, and invasion rates may change in the future as native ecosystems become more or less susceptible to invasion because of changes in climate. For example, evidence suggests that some plant invaders are favored under increased ambient CO2 levels, potentially leading to increased invasion with continued greenhouse gas emissions. In this work, I predict how western invasive plant species may also be affected by changes in climate variability. According to IPCC reports, rising ocean temperatures may change the frequency and intensity of El Niño events, potentially resulting in wetter El Niño years and/or more extreme and lengthier drought. In semi-arid systems, changing frequency or magnitude of extreme weather events may further shift the competitive balance between native and invasive species. For example, cheatgrass and yellow starthistle, both annual invaders, display high inter-annual variability in response to water availability. As a result, plants are larger and produce more seeds than native competitors during extreme wet years. This phenological response is so strong in cheatgrass communities that it can be observed in regional satellite records. Further, dense cheatgrass growth leads to a secondary feedback in the form of wildfire; higher density cheatgrass increases fire frequency in shrublands and enables further cheatgrass colonization. In this work, I synthesize knowledge of invasive plant phenological response under different climate conditions, drawing on information gathered through geographical mapping efforts at state or regional levels by university and agency researchers. Using the ranges of climate tolerance from current

  3. Spatial variability in growth-increment chronologies of long-lived freshwater mussels: Implications for climate impacts and reconstructions

    Science.gov (United States)

    Black, Bryan A.; Dunham, Jason B.; Blundon, Brett W.; Raggon, Mark F.; Zima, Daniela

    2010-01-01

    Estimates of historical variability in river ecosystems are often lacking, but long-lived freshwater mussels could provide unique opportunities to understand past conditions in these environments. We applied dendrochronology techniques to quantify historical variability in growth-increment widths in valves (shells) of western pearlshell freshwater mussels (Margaritifera falcata). A total of 3 growth-increment chronologies, spanning 19 to 26 y in length, were developed. Growth was highly synchronous among individuals within each site, and to a lesser extent, chronologies were synchronous among sites. All 3 chronologies negatively related to instrumental records of stream discharge, while correlations with measures of water temperature were consistently positive but weaker. A reconstruction of stream discharge was performed using linear regressions based on a mussel growth chronology and the regional Palmer Drought Severity Index (PDSI). Models based on mussel growth and PDSI yielded similar coefficients of prediction (R2Pred) of 0.73 and 0.77, respectively, for predicting out-ofsample observations. From an ecological perspective, we found that mussel chronologies provided a rich source of information for understanding climate impacts. Responses of mussels to changes in climate and stream ecosystems can be very site- and process-specific, underscoring the complex nature of biotic responses to climate change and the need to understand both regional and local processes in projecting climate impacts on freshwater species.

  4. Simulation of the Impact of Climate Variability on Malaria Transmission in the Sahel

    Science.gov (United States)

    Bomblies, A.; Eltahir, E.; Duchemin, J.

    2007-12-01

    A coupled hydrology and entomology model for simulation of malaria transmission and malaria transmitting mosquito population dynamics is presented. Model development and validation is done using field data and observations collected at Banizoumbou and Zindarou, Niger spanning three wet seasons, from 2005 through 2007. The primary model objective is the accurate determination of climate variability effects on village scale malaria transmission. Malaria transmission dependence on climate variables is highly nonlinear and complex. Temperature and humidity affect mosquito longevity, temperature controls parasite development rates in the mosquito as well as subadult mosquito development rates, and precipitation determines the formation and persistence of adequate breeding pools. Moreover, unsaturated zone hydrology influences overland flow, and climate controlled evapotranspiration rates and root zone uptake therefore also influence breeding pool formation. High resolution distributed hydrologic simulation allows representation of the small-scale ephemeral pools that constitute the primary habitat of Anopheles gambiae mosquitoes, the dominant malaria vectors in the Niger Sahel. Remotely sensed soil type, vegetation type, and microtopography rasters are used to assign the distributed parameter fields for simulation of the land surface hydrologic response to precipitation and runoff generation. Predicted runoff from each cell flows overland and into topographic depressions, with explicit representation of infiltration and evapotranspiration. The model's entomology component interacts with simulated pools. Subadult (aquatic stage) mosquito breeding is simulated in the pools, and water temperature dependent stage advancement rates regulate adult mosquito emergence into the model domain. Once emerged, adult mosquitoes are tracked as independent individual agents that interact with their immediate environment. Attributes relevant to malaria transmission such as gonotrophic

  5. Application of Remote Sensing to Assess the Impact of Short Term Climate Variability on Coastal Sedimentation

    Science.gov (United States)

    Menzel, W. Paul; Huh, Oscar K.; Walker, Nan

    2004-01-01

    The purpose of this joint University of Wisconsin (UW) and Louisiana State University (LSU) project has been to relate short term climate variation to response in the coastal zone of Louisiana in an attempt to better understand how the coastal zone is shaped by climate variation. Climate variation in this case largely refers to variation in surface wind conditions that affect wave action and water currents in the coastal zone. The primary region of focus was the Atchafalaya Bay and surrounding bays in the central coastal region of Louisiana. Suspended solids in the water column show response to wind systems both in quantity (through resuspension) and in the pattern of dispersement or transport. Wind systems associated with cold fronts are influenced by short term climate variation. Wind energy was used as the primary signature of climate variation in this study because winds are a significant influence on sediment transport in the micro-tidal Gilf of Mexico coastal zone. Using case studies, the project has been able to investigate the influence of short term climate variation on sediment transport. Wind energy data, collected daily for National Weather Service (NWS) stations at Lake Charles and New Orleans, LA, were used as an indicator of short term climate variation influence on seasonal time scales. A goal was to relate wind energy to coastal impact through sediment transport. This goal was partially accomplished by combining remote sensing and wind energy data. Daily high resolution remote sensing observations are needed to monitor the complex coastal zone environment, where winds, tides, and water level all interact to influence sediment transport. The NASA Earth Observing System (EOS) era brings hope for documenting and revealing response of the complex coastal transport mosaic through regular high spatial resolution observations from the Moderate resolution Imaging Spectrometer (MODIS) instrument. MODIS observations were sampled in this project for

  6. A Variable Resolution Gcm Simulation of The Impact of Future Land-use Changes On African Climate

    Science.gov (United States)

    Maynard, K.; Royer, J. F.; Chauvin, F.

    Simulations with atmospheric general circulation models (GCM) have generally shown a significant impact of large-scale anthropogenic changes in land cover, on the regional surface climate, particularly for the case of massive tropical deforesta- tion. However these simulations have usually been performed with idealized land- surface changes, and with horizontal resolutions of several hundred kilometers, which does not allow to represent in detail the geographical variations of the land surface processes and their possible feedbacks. To achieve a higher spatial resolution over a selected region, a variable resolution version of the ARPEGE-Climat model, with a zooming technique based on a conformal transformation of the sphere, has been ap- plied to time-slice simulations allowing to reach a resolution of about 100 km over Africa. For the validation of the model a control simulation for the current climate has been performed using a new vegetation database based on satellite data. A time-slice simulation for the middle of the 21-rst century has been performed using the SST anomaly patterns from a coupled atmosphere-ocean transient climate simulation per- formed with a lower resolution version of the ARPEGE-Climat under the conditions of the SRES-B2 scenario of IPCC. In order to specify realistic land cover changes the results of the integrated impact assessment model IMAGE 2.2 from RIVM (Bilthoven) have been used to compute land surface properties on a 0.5 grid over the conti- nents. The impact on the African monsoon of the expected land surface changes in a greenhouse-warmed climate simulated by the high resolution GCM will be illustrated and discussed in this presentation.

  7. Variability of the North Atlantic summer storm track: mechanisms and impacts on European climate

    International Nuclear Information System (INIS)

    The summertime variability of the extratropical storm track over the Atlantic sector and its links to European climate have been analysed for the period 1948–2011 using observations and reanalyses. The main results are as follows. (1) The dominant mode of the summer storm track density variability is characterized by a meridional shift of the storm track between two distinct paths and is related to a bimodal distribution in the climatology for this region. It is also closely related to the Summer North Atlantic Oscillation (SNAO). (2) A southward shift is associated with a downstream extension of the storm track and a decrease in blocking frequency over the UK and northwestern Europe. (3) The southward shift is associated with enhanced precipitation over the UK and northwestern Europe and decreased precipitation over southern Europe (contrary to the behaviour in winter). (4) There are strong ocean–atmosphere interactions related to the dominant mode of storm track variability. The atmosphere forces the ocean through anomalous surface fluxes and Ekman currents, but there is also some evidence consistent with an ocean influence on the atmosphere, and that coupled ocean–atmosphere feedbacks might play a role. The ocean influence on the atmosphere may be particularly important on decadal timescales, related to the Atlantic Multidecadal Oscillation (AMO). (letter)

  8. Solar Irradiance Variability and Its Impacts on the Earth Climate System

    Science.gov (United States)

    Harder, J. W.; Woods, T. N.

    The Sun plays a vital role in the evolution of the climates of terrestrial planets. Observations of the solar spectrum are now routinely made that span the wavelength range from the X-ray portion of the spectrum (5 nm) into the infrared to about 2400 nm. Over this very broad wavelength range, accounting for about 97% of the total solar irradiance, the intensity varies by more than 6 orders of magnitude, requiring a suite of very different and innovative instruments to determine both the spectral irradiance and its variability. The origins of solar variability are strongly linked to surface magnetic field changes, and analysis of solar images and magnetograms show that the intensity of emitted radiation from solar surface features in active regions has a very strong wavelength and magnetic field strength dependence. These magnetic fields produce observable solar surface features such as sunspots, faculae, and network structures that contribute in different ways to the radiated output. Semi-empirical models of solar spectral irradiance are able to capture much of the Sun's output, but this topic remains an active area of research. Studies of solar structures in both high spectral and spatial resolution are refining this understanding. Advances in Earth observation systems and high-quality three-dimensional chemical climate models provide a sound methodology to study the mechanisms of the interaction between Earth's atmosphere and the incoming solar radiation. Energetic photons have a profound effect on the chemistry and dynamics of the thermosphere and ionosphere, and these processes are now well represented in upper atmospheric models. In the middle and lower atmosphere the effects of solar variability enter the climate system through two nonexclusive pathways referred to as the top-down and bottom-up mechanisms. The top-down mechanism proceeds through the alteration of the photochemical rates that establish the middle atmospheric temperature structure and

  9. The impact of climate change on the drought variability over Australia

    Science.gov (United States)

    Kirono, D. G. C.; Hennessy, K.; Mpelasoka, F.; Bathols, J.; Kent, D.

    2009-04-01

    Drought has significant environmental and socio-economic impacts in Australia. Government assistance for drought events is guided by the current National Drought Policy (NDP). The Commonwealth Government provides support to farmers and rural communities under the Exceptional Circumstances (EC) arrangements and other drought programs, while state and territory governments also participate in the NDP and provide support measures of their own. To be classified as an EC event, the event must be rare, that is must not have occurred more than once on average in every 20-25 years. Given the likely increase in the area of the world affected by droughts in future due to climate change (IPCC, 2007), this paper presents assessments on how climate change may affect the concept of a one in 20-25 year event into the future for Australia. As droughts can be experienced and defined in different ways, many drought indices are available to monitor and to assess drought conditions. Commonly, these indices are categorised into four types: meteorological, hydrological, agricultural, and socio-economic. The meteorological drought indices are more widely used because they require data that are readily available and that they are relatively easy to calculate. However, meteorological drought indices based on rainfall alone fail to include the important contribution of evaporation. Here, the assessment is made using outputs of 13 global climate models (GCMs) and a meteorological drought index called the Reconnaissance Drought Index (RDI). It incorporates the aggregated deficits between the rainfall and the evaporative demand of the atmosphere. If the RDI were the sole trigger for EC declarations, then the mean projections indicate that more declarations would be likely in the future. As a comparison, results from an assessment based on other measures (temperature, rainfall, and soil wetness) will also be presented. IPCC, 2007: Climate Change 2007 - The physical Science Basis. Contribution

  10. Assessing the impact of climate variability on catchment water balance and vegetation cover

    Directory of Open Access Journals (Sweden)

    X. Xu

    2011-06-01

    Full Text Available Understanding the interactions among climate, vegetation cover and the water cycle lies at the heart of the study of watershed ecohydrology. Recently, considerable attention is being paid to the effect of climate variability (e.g., precipitation and temperature on catchment water balance and also associated vegetation cover. In this paper, we investigate the general pattern of long-term water balance and vegetation cover (as reflected in fPAR among 193 study catchments in Australia through statistical analysis. We then employ the elasticity analysis approach for quantifying the effects of climate variability on hydrologic partitioning (including total runoff, surface and subsurface runoff and on vegetation cover (including total, woody and non-woody vegetation cover. Based on the results of statistical analysis, we conclude that annual runoff (R, evapotranspiration (E and runoff coefficient (R/P all increase with vegetation cover for catchments in which woody vegetation is dominant and annual precipitation is relatively high. Annual evapotranspiration (E is mainly controlled by water availability rather than energy availability for catchments in relatively dry climates in which non-woody vegetation is dominant. The ratio of subsurface runoff to total runoff (Rg/R also increases with woody vegetation cover. Through the elasticity analysis of catchment runoff, it is shown that precipitation (P in the current year is the most important factor affecting the change in annual total runoff (R, surface runoff (Rs and subsurface runoff (Rg. The significance of other controlling factors is in the order of the annual precipitation in the previous year (P−1 and P−2, which represent the net effect of soil moisture, and the annual mean temperature (T in the current year. Change of P by +1 % causes a +3

  11. Ocean impact on decadal Atlantic climate variability revealed by sea-level observations

    Science.gov (United States)

    McCarthy, Gerard D.; Haigh, Ivan D.; Hirschi, Joël J.-M.; Grist, Jeremy P.; Smeed, David A.

    2015-05-01

    Decadal variability is a notable feature of the Atlantic Ocean and the climate of the regions it influences. Prominently, this is manifested in the Atlantic Multidecadal Oscillation (AMO) in sea surface temperatures. Positive (negative) phases of the AMO coincide with warmer (colder) North Atlantic sea surface temperatures. The AMO is linked with decadal climate fluctuations, such as Indian and Sahel rainfall, European summer precipitation, Atlantic hurricanes and variations in global temperatures. It is widely believed that ocean circulation drives the phase changes of the AMO by controlling ocean heat content. However, there are no direct observations of ocean circulation of sufficient length to support this, leading to questions about whether the AMO is controlled from another source. Here we provide observational evidence of the widely hypothesized link between ocean circulation and the AMO. We take a new approach, using sea level along the east coast of the United States to estimate ocean circulation on decadal timescales. We show that ocean circulation responds to the first mode of Atlantic atmospheric forcing, the North Atlantic Oscillation, through circulation changes between the subtropical and subpolar gyres--the intergyre region. These circulation changes affect the decadal evolution of North Atlantic heat content and, consequently, the phases of the AMO. The Atlantic overturning circulation is declining and the AMO is moving to a negative phase. This may offer a brief respite from the persistent rise of global temperatures, but in the coupled system we describe, there are compensating effects. In this case, the negative AMO is associated with a continued acceleration of sea-level rise along the northeast coast of the United States.

  12. Changes in atmospheric variability in a glacial climate and the impacts on proxy data: a model intercomparison

    Directory of Open Access Journals (Sweden)

    F. S. R. Pausata

    2009-09-01

    Full Text Available Using four different climate models, we investigate sea level pressure variability in the extratropical North Atlantic in the preindustrial climate (1750 AD and at the Last Glacial Maximum (LGM, 21 kyrs before present in order to understand how changes in atmospheric circulation can affect signals recorded in climate proxies.

    In general, the models exhibit a significant reduction in interannual variance of sea level pressure at the LGM compared to pre-industrial simulations and this reduction is concentrated in winter. For the preindustrial climate, all models feature a similar leading mode of sea level pressure variability that resembles the leading mode of variability in the instrumental record: the North Atlantic Oscillation (NAO. In contrast, the leading mode of sea level pressure variability at the LGM is model dependent, but in each model different from that in the preindustrial climate. In each model, the leading (NAO-like mode of variability explains a smaller fraction of the variance and also less absolute variance at the LGM than in the preindustrial climate.

    The models show that the relationship between atmospheric variability and surface climate (temperature and precipitation variability change in different climates. Results are model-specific, but indicate that proxy signals at the LGM may be misinterpreted if changes in the spatial pattern and seasonality of surface climate variability are not taken into account.

  13. Assessing the impact of climate variability on catchment water balance and vegetation cover

    Directory of Open Access Journals (Sweden)

    X. Xu

    2012-01-01

    Full Text Available Understanding the interactions among climate, vegetation cover and the water cycle lies at the heart of the study of watershed ecohydrology. Recently, considerable attention is being paid to the effect of climate variability on catchment water balance and also associated vegetation cover. In this paper, we investigate the general pattern of long-term water balance and vegetation cover (as reflected by fPAR among 193 study catchments in Australia through statistical analysis. We then employ the elasticity analysis approach for quantifying the effects of climate variability on hydrologic partitioning (including total, surface and subsurface runoff and on vegetation cover (including total, woody and non-woody vegetation cover. Based on the results of statistical analysis, we conclude that annual runoff (R, evapotranspiration (E and runoff coefficient (R/P increase with vegetation cover for catchments in which woody vegetation is dominant and annual precipitation is relatively high. Control of water available on annual evapotranspiration in non-woody dominated catchments is relatively stronger compared to woody dominated ones. The ratio of subsurface runoff to total runoff (Rg/R also increases with woody vegetation cover. Through the elasticity analysis of catchment runoff, it is shown that precipitation (P in current year is the most important factor affecting the change in annual total runoff (R, surface runoff (Rs and subsurface runoff (Rg. The significance of other controlling factors is in the order of annual precipitation in previous years (P−1 and P−2, which represents the net effect of soil moisture and annual mean temperature (T in current year. Change of P by +1% causes a +3.35% change of R, a +3.47% change of Rs and a +2.89% change of

  14. Evaluating Impact of Land Use Changes and Climate Variability on Economic Efficiency of Farming in Transboundary Watershed of Timor Island

    Directory of Open Access Journals (Sweden)

    Werenfridus Taena

    2016-07-01

    Full Text Available Indonesia and Timor-Leste development of border regions in Timor Island has brought land use changes, and when combined with climate variability it may cause flooding, drought, and impact of economic efficiency of farm crop. The research aimed to analyze: (i the effect of land use changes and climate variability on the floods and drought on the Tono Watershed, (ii the impact of flood, drought and production factors in yield and the economic efficiency of food crop farming. The analysis applied logit method for flood and drought. Frontier analysis to evaluate economic efficiency of farming. Logit analysis showed that the increase in the monthly rainfall and mix dryland farming, along with the decrease of forestry and paddy fields increase the flooding on Tono Watershed. The result further suggested by this analysis showed drought has caused by the increase of mix dryland farming and monthly temperature, and decrease of monthly rainfall. This led to a reduction in yield and economic efficiency of farm crops. Frontier analysis confirms the low economic efficiency of farming, whereas monoculture farming was 0.36 (affected by floods and drought and multicrop farming was 0.30 (affected by drought which is far from the efficiency standard ≥ 0.8.

  15. Impacts of human activities and climate variability on green and blue water flows in the Heihe River Basin in Northwest China

    OpenAIRE

    C. Zang; J. Liu; JIANG, L.; Gerten, D.

    2013-01-01

    Human activities and climate factors both affect the availability of water resources and the sustainability of water management. Especially in already dry regions, water has become more and more scarce with increasing requirements from growing population, economic development and diet shifts. Although progress has been made in understanding variability of runoff, the impacts of climate variability and human activities on flows of both green water (actual eva...

  16. Impacts of human activities and climate variability on green and blue water flows in the Heihe River Basin in Northwest China

    OpenAIRE

    C. Zang; J. Liu; JIANG, L.; Gerten, D.

    2013-01-01

    Human activities and climate factors both affect the availability of water resources and the sustainability of water management. Especially in already dry regions, water has become more and more scarce with increasing requirements from growing population, economic development and diet shifts. Although progress has been made in understanding variability of runoff, the impacts of climate variability and human activities on flows of both green water (actual evapotranspiration) and blue wa...

  17. Effects of seasonal climatic variability on several toxic contaminants in urban lakes: Implications for the impacts of climate change

    Institute of Scientific and Technical Information of China (English)

    Qiong Wu; Xinghui Xia; Xinli Mou; Baotong Zhu; Pujun Zhao; Haiyang Dong

    2014-01-01

    Climate change is supposed to have influences on water quality and ecosystem.However,only few studies have assessed the effect of climate change on environmental toxic contaminants in urban lakes.In this research,response of several toxic contaminants in twelve urban lakes in Beijing,China,to the seasonal variations in climatic factors was studied.Fluorides,volatile phenols,arsenic,selenium,and other water quality parameters were analyzed monthly from 2009 to 2012.Multivariate statistical methods including principle component analysis,cluster analysis,and multiple regression analysis were performed to study the relationship between contaminants and climatic factors including temperature,precipitation,wind speed,and sunshine duration.Fluoride and arsenic concentrations in most urban lakes exhibited a significant positive correlation with temperature/precipitation,which is mainly caused by rainfall induced diffuse pollution.A negative correlation was observed between volatile phenols and temperature/precipitation,and this could be explained by their enhanced volatilization and biodegradation rates caused by higher temperature.Selenium did not show a significant response to climatic factor variations,which was attributed to low selenium contents in the lakes and soils.Moreover,the response degrees of contaminants to climatic variations differ among lakes with different contamination levels.On average,temperature/precipitation contributed to 8%,15%,and 12% of the variations in volatile phenols,arsenic,and fluorides,respectively.Beijing is undergoing increased temperature and heavy rainfall frequency during the past five decades.This study suggests that water quality related to fluoride and arsenic concentrations of most urban lakes in Beijing is becoming worse under this climate change trend.

  18. Changes in atmospheric variability in a glacial climate and the impacts on proxy data: a model intercomparison

    Directory of Open Access Journals (Sweden)

    F. S. R. Pausata

    2009-03-01

    Full Text Available We investigate sea level pressure variability in the extratropical North Atlantic in the preindustrial climate (1750 A.D. and at the Last Glacial Maximum (LGM, 21 kyr before present using four climate models. In general, the models exhibit a significant reduction in interannual variance of sea level pressure during the LGM compared to pre-industrial simulations and this reduction is concentrated in winter.

    For the preindustrial climate, all the models feature a similar leading mode (EOF of sea level pressure variability that is also similar to the leading mode of variability in the instrumental record: the North Atlantic Oscillation (NAO. In contrast, the leading mode of sea level pressure variability during the LGM is model dependent, but in each model different from that in the preindustrial climate. In each model, the leading (NAO-like mode of variability explains a smaller fraction of the variance and also less absolute variance in the LGM than in the preindustrial. The leading (NAO-like mode of sea level pressure variability is shifted southward in the LGM simulations relative to the preindustrial simulations.

    Finally, we correlate the leading mode of sea level pressure variability with surface temperature and precipitation within each model and for the two time periods. In the preindustrial climate, the leading mode of sea level pressure variability is similar from model to model and the temperature and precipitation correlation patterns are also similar. In contrast, since the models find different dominant modes of sea level pressure variability for the LGM climate, they also disagree on the associated patterns of temperature and precipitation variability. Assuming stationarity of the relationship between surface climate and the leading mode of sea level pressure variability could lead to a misinterpretation of signals recorded in proxy data.

  19. Revealing the Impact of Climate Variability on the Wind Resource Using Data Mining Techniques (Poster)

    Energy Technology Data Exchange (ETDEWEB)

    Clifton, A.; Lundquist, J.

    2011-12-01

    A data mining technique called 'k-means clustering' can be used to group winds at the NWTC into 4 major clusters. The frequency of some winds in the clusters is correlated with regional pressure gradients and climate indices. The technique could also be applied to wind resource assessment and selecting scenarios for flow modeling.

  20. Impact of bushfire and climate variability on streamflow from forested catchments in southeast Australia

    OpenAIRE

    Zhou, Y.; Zhang, Y.; Vaze, J.; Lane, P; Xu, S.

    2013-01-01

    Most of the surface water for natural environmental and human water uses in southeast Australia is sourced from forested catchments located in the higher rainfall areas. Water yield of these catchments is mainly affected by climatic conditions, but it is also greatly affected by vegetation cover change. Bushfires are a major natural disturbance in forested catchments and potentially modify the water yield of the catchments through changes to evapotranspirat...

  1. Economic Analysis of Climate Variability Impact on Malaria Prevalence: The Case of Ghana

    OpenAIRE

    Akpalu, Wisdom; Codjoe, Samuel

    2013-01-01

    A number of studies exist on the relationship between climatic factors and malaria prevalence. However, due to scarcity of data, most of the studies are based on biophysical experiments and do not control for socioeconomic covariates. This research, which uses data on Ghana, contributes to the thin literature that addresses this limitation. We found that humidity and rainfall predict malaria prevalence. Furthermore, our results suggest that malaria prevalence increases with rainfall, the prop...

  2. Climate variability and change

    CERN Document Server

    Grassl, H

    1998-01-01

    Many factors influence climate. The present knowledge concerning the climate relevance of earth orbital parameters, solar luminosity, volcanoes, internal interactions, and human activities will be reported as well as the vulnerability of emission scenarios for given stabilization goals for greenhouse gas concentrations and the main points of the Kyoto Protocol

  3. Climate impacts on the structures of the North Pacific air-sea CO2 flux variability

    Directory of Open Access Journals (Sweden)

    Y. Nojiri

    2011-05-01

    Full Text Available Some dominant spatial and temporal structures of the North Pacific air-sea CO2 fluxes in response to the Pacific Decadal Oscillation (PDO are identified in four data products from four independent sources: an assimilated CO2 flux product, two forward model solutions, and a gridded pCO2 dataset constructed with a neural network approach. The interannual variability of CO2 flux is found to be an order of magnitude weaker compared to the seasonal cycle of CO2 flux in the North Pacific. A statistical approach is employed to quantify the signal-to-noise ratio in the reconstructed dataset to delineate the representativity errors. The dominant variability with a signal-to-noise ratio above one is identified and its correlations with PDO are examined. A tentative four-box structure in the North Pacific air-sea CO2 flux variability linked to PDO emerges in which two positively correlated boxes are oriented in the northwest and southeast directions and contrarily, the negatively correlated boxes are oriented in the northeast and southwest directions. This pattern is verified with the CO2 and pCO2 from four products and its relations to the interannual El Niño-Southern Oscillation (ENSO and lower-frequency PDO are separately identified. A combined EOF analysis between air-sea CO2 flux and key variables representing ocean-atmosphere interactions is carried out to elicit robust oscillations in the North Pacific CO2 flux in response to the PDO. The proposed spatial and temporal structures of the North Pacific CO2 fluxes are insightful since they separate the secular trends of the surface ocean carbon from the interannual variability. The regional characterization of the North Pacific in terms of PDO and CO2 flux variability is also instructive for determining the homogeneous oceanic domains for the Regional Carbon Cycle and Assessment Processes (RECCAP.

  4. Impact of Holocene climate variability on lacustrine records and human settlements in South Greenland

    Science.gov (United States)

    Guillemot, T.; Bichet, V.; Simonneau, A.; Rius, D.; Massa, C.; Gauthier, E.; Richard, H.; Magny, M.

    2015-11-01

    Due to its sensitivity to climate changes, south Greenland is a particularly suitable area to study past global climate changes and their influence on locale Human settlements. A paleohydrological investigation was therefore carried out on two river-fed lakes: Lake Qallimiut and Little Kangerluluup, both located close to the Labrador Sea in the historic farming center of Greenland. Two sediment cores (QAL-2011 and LKG-2011), spanning the last four millennia, were retrieved and showed similar thin laminae, described by high magnetic susceptibility and density, high titanium and TOC / TN atomic ratio, and coarse grain size. They are also characterized either by inverse grading followed by normal grading or by normal grading only and a prevalence of red amorphous particles and lignocellulosic fragments, typical of flood deposits. Flood events showed similar trend in both records: they mainly occurred during cooler and wetter periods characterized by weaker Greenlandic paleo-temperatures, substantial glacier advances, and a high precipitation on the Greenlandic Ice Sheet and North Atlantic ice-rafting events. They can therefore be interpreted as a result of ice and snow-melting episodes. They occurred especially during rapid climate changes (RCC) such as the Middle to Late Holocene transition around 2250 BC, the Sub-boreal/Sub-atlantic transition around 700 BC and the Little Ice Age (LIA) between AD 1300 and AD 1900, separated by cycles of 1500 years and driven by solar forcing. These global RCC revealed by QAL-2011 and LKG-2011 flood events may have influenced Human settlements in south Greenland, especially the paleo-Eskimo cultures and the Norse settlement, and have been mainly responsible for their demise.

  5. Spatio-Temporal Impacts of Biofuel Production and Climate Variability on Water Quantity and Quality in Upper Mississippi River Basin

    OpenAIRE

    Debjani Deb; Pushpa Tuppad; Prasad Daggupati; Raghavan Srinivasan; Deepa Varma

    2015-01-01

    Impact of climate change on the water resources of the United States exposes the vulnerability of feedstock-specific mandated fuel targets to extreme weather conditions that could become more frequent and intensify in the future. Consequently, a sustainable biofuel policy should consider: (a) how climate change would alter both water supply and demand; and (b) in turn, how related changes in water availability will impact the production of biofuel crops; and (c) the environmental implications...

  6. Methodological principles for the evaluation of impact of the variability and the climatic change in the human health, a statistical focus

    International Nuclear Information System (INIS)

    Signal detection of climate variability or change and the evaluation of its specific effects, requires an understanding of the variations in the observed data, which describe the natural climate variability and change signals. It is also necessary to understand the complex interactions that make up the climate system. In the present work, an unusual methodological approach is taken to evaluate the effects and impacts of climate variability and change on the behaviour of different diseases, on the basis of practical experience of its application in four countries of the Caribbean, Central and South America: Cuba, Panama, Bolivia and Paraguay. For the determination of the climate signal change multivariate analysis techniques (empirical orthogonal functions) were used, combined with robust methods of time series decomposition (decomposition by median). They allowed us to describe the changes observed in the seasonal patterns of climate and epidemiological diseases for the period 1991-1999, with respect to the period 1961-1990. These results were used to build an autoregressive model with non-constant variance, with a climate index based on the signals obtained from the decompositions, which enters the model as an exogenous variable in order to make projections of the diseases

  7. Solar Variability and Planetary Climates

    CERN Document Server

    Calisesi, Y; Gray, L; Langen, J; Lockwood, M

    2007-01-01

    Variations in solar activity, as revealed by variations in the number of sunspots, have been observed since ancient times. To what extent changes in the solar output may affect planetary climates, though, remains today more than ever a subject of controversy. In 2000, the SSSI volume on Solar Variability and Climate reviewed the to-date understanding of the physics of solar variability and of the associated climate response. The present volume on Solar Variability and Planetary Climates provides an overview of recent advances in this field, with particular focus at the Earth's middle and lower atmosphere. The book structure mirrors that of the ISSI workshop held in Bern in June 2005, the collection of invited workshop contributions and of complementary introductory papers synthesizing the current understanding in key research areas such as middle atmospheric processes, stratosphere-troposphere dynamical coupling, tropospheric aerosols chemistry, solar storm influences, solar variability physics, and terrestri...

  8. Mirador - Climate Variability and Change

    Data.gov (United States)

    National Aeronautics and Space Administration — Earth Science data access made simple. NASA's role in climate variability study is centered around providing the global scale observational data sets on oceans and...

  9. Impacts of climate variability on the runoff in the South Eastern part of Bulgaria

    International Nuclear Information System (INIS)

    The basic climatic factors, which affect the river runoff, are atmospheric precipitation and temperature. On the basis of the set of data from some hydro-meteorological gauging stations with more than 45 years observations have been studied the effect of meteorological conditions on runoff in the southeastern region of Bulgaria. The change of the temperature, precipitation and runoff over the southeastern Bulgarian catchments are investigated and analyzed. During the application of several statistical tests was found that there are changes in the runoff, which are not caused by the man's activity. The features in the variations of above mentioned hydro-meteorological elements and their inherent trends are determined. The results of this study show that the runoff decreases considerably all over the studied region in the last years. An attempt to find a cause of the changes was done. The significant tendency to gradual reduction of runoff in the region is due to considerably decrease of the precipitation all over the Balkans. The study shows that high temperatures and low precipitation conduct to drought in the region and appears unsuitable conditions for the river runoff feeding and development of plants. (Author)

  10. Climate change or variable weather

    DEFF Research Database (Denmark)

    Baron, Nina; Kjerulf Petersen, Lars

    2015-01-01

    understand homeowners’ perception of climate change and local flood risk. Ingold argues that those perceptions are shaped by people’s experiences with and connections to their local landscape. People experience the local variability of the weather, and not global climate change as presented in statistical...

  11. The potential impacts of climate variability and change on air pollution-related health effects in the United States.

    OpenAIRE

    Bernard, S. M.; Samet, J M; Grambsch, A; Ebi, K L; Romieu, I

    2001-01-01

    Climate change may affect exposures to air pollutants by affecting weather, anthropogenic emissions, and biogenic emissions and by changing the distribution and types of airborne allergens. Local temperature, precipitation, clouds, atmospheric water vapor, wind speed, and wind direction influence atmospheric chemical processes, and interactions occur between local and global-scale environments. If the climate becomes warmer and more variable, air quality is likely to be affected. However, the...

  12. Sunflower yield and climatic variables

    OpenAIRE

    González J.; Mancuso N.; Ludueña P.

    2013-01-01

    A group of hybrids with higher oil yield was selected from the comparative yield trials carried out in the EEA Pergamino, during seasons 2004-2005, 2005-2006 and 2006-07. The objective was to study the associations between seed yield, oil content, oil yield and climatic variables obtained from two methods: stepwise and principal component analysis. Both methods arrived at similar results confirming the associations between yield and climatic variables. Posi...

  13. Land-Cover Phenologies and Their Relation to Climatic Variables in an Anthropogenically Impacted Mediterranean Coastal Area

    Directory of Open Access Journals (Sweden)

    Encarni I. Hernández

    2010-03-01

    Full Text Available Mediterranean coastal areas are experiencing rapid land cover change caused by human-induced land degradation and extreme climatic events. Vegetation index time series provide a useful way to monitor vegetation phenological variations. This study quantitatively describes Enhanced Vegetation Index (EVI temporal changes for Mediterranean land-covers from the perspective of vegetation phenology and its relation with climate. A time series from 2001 to 2007 of the MODIS Enhanced Vegetation Index 16-day composite (MOD13Q1 was analyzed to extract anomalies (by calculating z-scores and frequency domain components (by the Fourier Transform. Vegetation phenology analyses were developed for diverse land-covers for an area in south Alicante (Spain providing a useful way to analyze and understand the phenology associated to those land-covers. Time series of climatic variables were also analyzed through anomaly detection techniques and the Fourier Transform. Correlations between EVI time series and climatic variables were computed. Temperature, rainfall and radiation were significantly correlated with almost all land-cover classes for the harmonic analysis amplitude term. However, vegetation phenology was not correlated with climatic variables for the harmonic analysis phase term suggesting a delay between climatic variations and vegetation response.

  14. Impacts of human activities and climate variability on green and blue water flows in the Heihe River Basin in Northwest China

    Science.gov (United States)

    Zang, C.; Liu, J.; Jiang, L.; Gerten, D.

    2013-07-01

    Human activities and climate factors both affect the availability of water resources and the sustainability of water management. Especially in already dry regions, water has become more and more scarce with increasing requirements from growing population, economic development and diet shifts. Although progress has been made in understanding variability of runoff, the impacts of climate variability and human activities on flows of both green water (actual evapotranspiration) and blue water (discharge accumulated in the river network) remain less well understood. We study the spatial patterns of blue and green water flows and the impacts on them of human activities and climate variability as simulated by the Soil and Water Assessment Tool (SWAT) for an inland Heihe river basin located in Northwest China. The results show that total green and blue water flow increased from 1980 to 2005, mainly as a result of climate variability (upward precipitation trends). Direct human activities did not significantly change the total green and blue water flow. However, land use change led to a transformation of 206 million m3 from green to blue water flow, while farmland irrigation expansion resulted in a transformation of 66 million m3 from blue to green water flow. The synchronous climate variability caused an increase of green water flow by 469 million m3 and an increase of blue water flow by 146 million m3 at the river basin level, while the geographical distribution showed an uneven change even with reductions of water flows in western sub-basins at midstream. The results are helpful to benchmark the water resources in the context of global change in the inland river basins in China. This study also provides a general approach to investigate the impacts of historical human activities and climate variability on green and blue water flows at the river basin level.

  15. Impacts of human activities and climate variability on green and blue water flows in the Heihe River Basin in Northwest China

    Directory of Open Access Journals (Sweden)

    C. Zang

    2013-07-01

    Full Text Available Human activities and climate factors both affect the availability of water resources and the sustainability of water management. Especially in already dry regions, water has become more and more scarce with increasing requirements from growing population, economic development and diet shifts. Although progress has been made in understanding variability of runoff, the impacts of climate variability and human activities on flows of both green water (actual evapotranspiration and blue water (discharge accumulated in the river network remain less well understood. We study the spatial patterns of blue and green water flows and the impacts on them of human activities and climate variability as simulated by the Soil and Water Assessment Tool (SWAT for an inland Heihe river basin located in Northwest China. The results show that total green and blue water flow increased from 1980 to 2005, mainly as a result of climate variability (upward precipitation trends. Direct human activities did not significantly change the total green and blue water flow. However, land use change led to a transformation of 206 million m3 from green to blue water flow, while farmland irrigation expansion resulted in a transformation of 66 million m3 from blue to green water flow. The synchronous climate variability caused an increase of green water flow by 469 million m3 and an increase of blue water flow by 146 million m3 at the river basin level, while the geographical distribution showed an uneven change even with reductions of water flows in western sub-basins at midstream. The results are helpful to benchmark the water resources in the context of global change in the inland river basins in China. This study also provides a general approach to investigate the impacts of historical human activities and climate variability on green and blue water flows at the river basin level.

  16. The Med-CORDEX initiative: towards fully coupled Regional Climate System Models to study the Mediterranean climate variability, change and impact

    Science.gov (United States)

    Somot, S.; Ruti, P.

    2012-04-01

    The Mediterranean region is considered as particularly vulnerable to climate variability and change (Giorgi, 2006; IPCC, 2007), in particular, to changes in its regional water cycle. This climate vulnerability is a key issue for the 500 million inhabitants living in the 30 Mediterranean countries. In addition, the Mediterranean basin is a good case study for climate regionalization. It is indeed surrounded by various and complex topography channelling regional winds (Mistral, Tramontane, Bora, Etesian, Sirocco) than defined local climate. Many small-size islands limit the low-level air flow and its coastline is particularly complex. Strong land-sea contrast, land-atmosphere feedback, intense air-sea coupling and aerosol-radiation interaction are also among the regional characteristics to take into account when dealing with the Mediterranean climate modeling. What is true for the Mediterranean climate is also true for the Mediterranean Sea that show complex bathymetry including narrow and shallow straits, a strong eddy activity and various distinct and interacting water masses. For all these reasons, the Mediterranean area has been chosen as a CORDEX sub-domain (MED) leading to the Med-CORDEX initiative endorsed by Med-CLIVAR and HyMeX. In addition to the core CORDEX framework (Atmosphere-RCM, 50 km, ERA-Interim, RCP4.5, RCP8.5), two more tiers have been defined for Med-CORDEX. The first one would like to assess the added-value of higher-resolution RCMs pushing the horizontal resolution up to 10 km. The second one will serve to test new regional climate modeling tools called Regional Climate System Models (RCSM) including a high-resolution and coupled representation of all the physical components of the regional climate system: atmosphere, land surface, vegetation, surface hydrology, rivers and ocean. In addition, the Med-CORDEX initiative is strongly coordinated with the HyMeX program that plans large field campaigns within the area of interest, development of new

  17. Processes Understanding of Decadal Climate Variability

    Science.gov (United States)

    Prömmel, Kerstin; Cubasch, Ulrich

    2016-04-01

    The realistic representation of decadal climate variability in the models is essential for the quality of decadal climate predictions. Therefore, the understanding of those processes leading to decadal climate variability needs to be improved. Several of these processes are already included in climate models but their importance has not yet completely been clarified. The simulation of other processes requires sometimes a higher resolution of the model or an extension by additional subsystems. This is addressed within one module of the German research program "MiKlip II - Decadal Climate Predictions" (http://www.fona-miklip.de/en/) with a focus on the following processes. Stratospheric processes and their impact on the troposphere are analysed regarding the climate response to aerosol perturbations caused by volcanic eruptions and the stratospheric decadal variability due to solar forcing, climate change and ozone recovery. To account for the interaction between changing ozone concentrations and climate a computationally efficient ozone chemistry module is developed and implemented in the MiKlip prediction system. The ocean variability and air-sea interaction are analysed with a special focus on the reduction of the North Atlantic cold bias. In addition, the predictability of the oceanic carbon uptake with a special emphasis on the underlying mechanism is investigated. This addresses a combination of physical, biological and chemical processes.

  18. Mediterranean climate modelling: variability and climate change scenarios

    International Nuclear Information System (INIS)

    Air-sea fluxes, open-sea deep convection and cyclo-genesis are studied in the Mediterranean with the development of a regional coupled model (AORCM). It accurately simulates these processes and their climate variabilities are quantified and studied. The regional coupling shows a significant impact on the number of winter intense cyclo-genesis as well as on associated air-sea fluxes and precipitation. A lower inter-annual variability than in non-coupled models is simulated for fluxes and deep convection. The feedbacks driving this variability are understood. The climate change response is then analysed for the 21. century with the non-coupled models: cyclo-genesis decreases, associated precipitation increases in spring and autumn and decreases in summer. Moreover, a warming and salting of the Mediterranean as well as a strong weakening of its thermohaline circulation occur. This study also concludes with the necessity of using AORCMs to assess climate change impacts on the Mediterranean. (author)

  19. Impact of Climate Variability on Prevalence of Urinary Schistosomiasis over Sunyani in the Transition Belt of Ghana

    Science.gov (United States)

    Tay, S. K.; Amekudzi, L. K.; Tagoe, G.

    2012-04-01

    A study has been conducted to determine the impact of climate variability on Schistosoma haematobium infection among patients and school children in Sunyani between 2006 and 2009. Urine samples from the subjects were collected and examined in the laboratory using the filtration technique for the detection and quantification of Schistosomiasis haematobium eggs. The prevalence rate of urinary schistosomiasis at the Sunyani Regional Hospital for 2006, 2007, 2008 and 2009 were found to be 0.24%, 0.55%, 0.55% and 0.75% respectively while that for Methodist Junior High School in 2008 and 2009 were 60.1% and 60.3% respectively. A decrease in the relative humidity and average annual rainfall were identified as factors contributory to the increase in urinary Schistosomiasis prevalence rate. The temperature values obtained throughout the study period did not have any significant effect on the prevalence rate. The temperature values, however, were those that enhanced cercarial incubation (15-35˚C) with a resultant increase in shedding of cercariae leading to more infections among water contacts. The infection rate due to stream Amama was 20.1%, while that due to river Tano was 36.6%. The highest risk group was children aged 15-19 years. Praziquantel was administered to treat the infection, producing a cure rate of 93%. Recognition of urinary Schistosomiasis as a public health problem in Ghana is the main challenge to prevention and control of the disease.

  20. Human activity and climate variability impacts on sediment discharge and runoff in the Yellow River of China

    Science.gov (United States)

    He, Yi; Wang, Fei; Mu, Xingmin; Guo, Lanqin; Gao, Peng; Zhao, Guangju

    2016-04-01

    We analyze the variability of sediment discharge and runoff in the Hekou-Longmen segment in the middle reaches of the Yellow River, China. Our analysis is based on Normalized Difference Vegetation Index (NDVI), sediment discharge, runoff, and monthly meteorological data (1961-2010). The climate conditions are controlled via monthly regional average precipitation and potential evapotranspiration (ET0) that are calculated with the Penman-Monteith method. Data regarding water and soil conservation infrastructure and their effects were investigated as causal factors of runoff and sediment discharge changes. The results indicated the following conclusions: (1) The sediment concentration, sediment discharge, and annual runoff, varied considerably during the study period and all of these factors exhibited larger coefficients of variation than ET0 and precipitation. (2) Sediment discharge, annual runoff, and sediment concentration significantly declined over the study period in a linear fashion. This was accompanied by an increase in ET0 and decline in precipitation that were not significant. (3) Within paired years with similar precipitation and potential evapotranspiration conditions (SPEC), all pairs showed a decline in runoff, sediment discharge, and sediment concentration. (4) Human impacts in this region were markedly high as indicated by NDVI, and soil and water measurements, and especially the soil and water conservation infrastructure resulting in an approximately 312 Mt year-1 of sediment deposition during 1960-1999.

  1. Climate Trends and Impacts in China

    OpenAIRE

    Sall, Chris

    2013-01-01

    This discussion paper summarizes observed and projected trends in extreme weather events, present-day climate variability, and future climate change and their impacts on China's different regions. Findings are presented from China's national assessment report on climate change (2007) and second national assessment report on climate change (2011) as well as other studies by Chinese and inte...

  2. Assessing the impact of climate variability and climate change on runoff in West Africa: The case of Senegal and Nakambe River basins

    OpenAIRE

    Karambiri, H.; García Galiano, S.G.; J. D. Giraldo; Yacouba, H.; Ibrahim, B; Barbier, B.; Polcher, J.

    2011-01-01

    West Africa and its people are very vulnerable to climate variability and changes. Increasing the knowledge of plausible trends of rainfall dry spell lengths (DSL) in the rainy season, and of runoff, enables the assessment of vulnerability and adaptive capacity of the system. These predictions are crucial from a water management and policy perspective. The analyses based on regional climate models (RCMs) and observed datasets exhibit non-stationary behavior and an increase of DSL. Our results...

  3. Spatio-Temporal Impacts of Biofuel Production and Climate Variability on Water Quantity and Quality in Upper Mississippi River Basin

    Directory of Open Access Journals (Sweden)

    Debjani Deb

    2015-06-01

    Full Text Available Impact of climate change on the water resources of the United States exposes the vulnerability of feedstock-specific mandated fuel targets to extreme weather conditions that could become more frequent and intensify in the future. Consequently, a sustainable biofuel policy should consider: (a how climate change would alter both water supply and demand; and (b in turn, how related changes in water availability will impact the production of biofuel crops; and (c the environmental implications of large scale biofuel productions. Understanding the role of biofuels in the water cycle is the key to understanding many of the environmental impacts of biofuels. Therefore, the focus of this study is to model the rarely explored interactions between land use, climate change, water resources and the environment in future biofuel production systems. Results from this study will help explore the impacts of the US biofuel policy and climate change on water and agricultural resources. We used the Soil and Water Assessment Tool (SWAT to analyze the water quantity and quality consequences of land use and land management related changes in cropping conditions (e.g., more use of marginal lands, greater residue harvest, increased yields, plus management practices due to biofuel crops to meet the Renewable Fuel Standard target on water quality and quantity.

  4. Climate Impacts on Human Health

    Science.gov (United States)

    ... Climate Change Impacts Human Health Impacts Human Health Climate Impacts on Human Health Climate Impacts on Alaska On This Page Temperature-Related ... very old) are especially vulnerable to health impacts. Climate Change Affects Human Health In 2016, the U.S. ...

  5. Solar variability, weather, and climate

    Science.gov (United States)

    1982-01-01

    Advances in the understanding of possible effects of solar variations on weather and climate are most likely to emerge by addressing the subject in terms of fundamental physical principles of atmospheric sciences and solar-terrestrial physis. The limits of variability of solar inputs to the atmosphere and the depth in the atmosphere to which these variations have significant effects are determined.

  6. Climate change - the impacts

    International Nuclear Information System (INIS)

    This special dossier about the impacts of climate change is made of 6 contributions dealing with: the mitigation of climate effects and how to deal with them (Bertrand Reysset); how to dare and transmit (Laurent Billes-Garabedian); littoral risks, the Pas-de-Calais example (Julien Henique); extreme meteorological events and health impacts (Mathilde Pascal, Philippe Pirard, Yvon Motreff); Biodiversity and climate: the janus of global change (Robert Barbault, Jacques Weber); adapting agriculture to dryness and temperatures (Philippe Gate); Paris and the future heats of the year 2100 (Jean-Luc Salagnac, Julien Desplat, Raphaelle Kounkou-Arnaud)

  7. Climate Change and Variability in Ghana: Stocktaking

    Directory of Open Access Journals (Sweden)

    Felix A. Asante

    2014-12-01

    Full Text Available This paper provides a holistic literature review of climate change and variability in Ghana by examining the impact and projections of climate change and variability in various sectors (agricultural, health and energy and its implication on ecology, land use, poverty and welfare. The findings suggest that there is a projected high temperature and low rainfall in the years 2020, 2050 and 2080, and desertification is estimated to be proceeding at a rate of 20,000 hectares per annum. Sea-surface temperatures will increase in Ghana’s waters and this will have drastic effects on fishery. There will be a reduction in the suitability of weather within the current cocoa-growing areas in Ghana by 2050 and an increase evapotranspiration of the cocoa trees. Furthermore, rice and rooted crops (especially cassava production are expected to be low. Hydropower generation is also at risk and there will be an increase in the incidence rate of measles, diarrheal cases, guinea worm infestation, malaria, cholera, cerebro-spinal meningitis and other water related diseases due to the current climate projections and variability. These negative impacts of climate change and variability worsens the plight of the poor, who are mostly women and children.

  8. Impact of socio-economic trends and climate variability on the occurrence and severity of blue water shortage and stress events at the global scale

    Science.gov (United States)

    Veldkamp, Ted I. E.; Wada, Yoshihide; de Moel, Hans; Kummu, Matti; Aerts, Jeroen C. J. H.; Ward, Philip J.

    2014-05-01

    Changes in available fresh water resources (i.e. water in rivers, lakes, and reservoirs), together with changes in water use, force our society to adapt continuously to drought and water scarcity conditions. The inadequate amount of fresh water is recognized as one of the most important global risks for the near future. Whilst several studies assess the role of long term climate change and socio-economic trends on global blue water availability and scarcity events, the impact of climate variability is less well understood. Taking into account inter-annual climate variability, however, is important as it may offset other factors of change (e.g. socio-economic development, long term climate change) at the regional scale, impacting the efficiency of adaptation strategies. The tailoring of adaptation strategies to specific regions requires also more insights in the specific character of water scarcity events, being solely demand (sector-specific)- or population-driven, or driven by both. Only few studies, however, have executed such assessment and a global analysis distinguishing water use sector- and climate variability-specific water scarcity events is lacking. In this contribution, we evaluate the impact of socio-economic trends and inter-annual climate variability on the occurrence and severity of blue water scarcity events. This is done at the global scale over the time period 1960-2000, while distinguishing two main types of scarcity: apparent, demand-driven, water stress and real, population-driven, water shortage. Subsequently, demand-driven water stress was broken down into water stress being solely irrigation-, economy-, or population-driven, or driven by all the causes. The results indicate that both socio-economic trends and climate variability impact the frequency and severity of water shortage and stress events. The results differ significantly regionally, both in sign (+/-) and in relative contribution. Furthermore, the results show a spatial

  9. Impact of subgrid-scale radiative heating variability on the stratocumulus-to-trade cumulus transition in climate models

    Energy Technology Data Exchange (ETDEWEB)

    Xiao, Heng; Gustafson, William I.; Wang, Hailong

    2014-04-29

    Subgrid-scale interactions between turbulence and radiation are potentially important for accurately reproducing marine low clouds in climate models. To better understand the impact of these interactions, the Weather Research and Forecasting (WRF) model is configured for large eddy simulation (LES) to study the stratocumulus-to-trade cumulus (Sc-to-Cu) transition. Using the GEWEX Atmospheric System Studies (GASS) composite Lagrangian transition case and the Atlantic Trade Wind Experiment (ATEX) case, it is shown that the lack of subgrid-scale turbulence-radiation interaction, as is the case in current generation climate models, accelerates the Sc-to-Cu transition. Our analysis suggests that in cloud-topped boundary layers subgrid-scale turbulence-radiation interactions contribute to stronger production of temperature variance, which in turn leads to stronger buoyancy production of turbulent kinetic energy and helps to maintain the Sc cover.

  10. Impact of Climate Variables on Revenue of Major Food Crops in Ghana : Ricardian Cross-Sectional Analysis

    OpenAIRE

    Issahaku, Zakaria Amidu; Maharjan, Keshav Lall

    2013-01-01

    This study analyzes the impact of climate on net revenues of five major food crops in Ghana using 2005 national survey data. A multinomial logit regression is used to correct for crop selection bias in estimation of net revenue per hectare. Results of a multinomial logit regression show that farmers are likely to switch from the cultivation of maize, sorghum and rice to cassava and yam with marginal warming. Marginal increase in rainfall prompts farmers to switch from cassava and yam to the c...

  11. Tropical deforestation and climate variability

    Energy Technology Data Exchange (ETDEWEB)

    Voldoire, A.; Royer, J.F. [CNRM/GMGEC/UDC, Meteo-France, 42 Avenue G. Coriolis, 31057, Toulouse Cedex 1 (France)

    2004-07-01

    A new tropical deforestation experiment has been performed, with the ARPEGE-Climat atmospheric global circulation model associated with the ISBA land surface scheme. Simulations are forced with observed monthly mean sea surface temperatures and thus inter-annual variability of the ocean system is taken into account. The local mean response to deforestation over Amazonia and Africa is relatively weak compared with most published studies and compensation effects are particularly important. However, a large increase in daily maximum temperatures is obtained during the dry season when soil water stress dominates. The analysis of daily variability shows that the distributions of daily minimum and maximum temperatures are noticeably modified with an increase in extreme temperatures. Daily precipitation amounts also indicate a weakening of the convective activity. Conditions for the onset of convection are less frequently gathered, particularly over southern Amazonia and western equatorial Africa. At the same time, the intensity of convective events is reduced, especially over equatorial deforested regions. The inter-annual variability is also enhanced. For instance, El Nino events generally induce a large drying over northern Amazonia, which is well reproduced in the control simulation. In the deforested experiment, a positive feedback effect leads to a strong intensification of this drying and a subsequent increase in surface temperature. The change in variability as a response to deforestation can be more crucial than the change of the mean climate since more intense extremes could be more detrimental for agriculture than an increase in mean temperatures. (orig.)

  12. Climate Variability over India and Bangladesh from the Perturbed UK Met Office Hadley Model: Impacts on Flow and Nutrient Fluxes in the Ganges Delta System

    Science.gov (United States)

    Whitehead, P. G.; Caesar, J.; Crossman, J.; Barbour, E.; Ledesma, J.; Futter, M. N.

    2015-12-01

    A semi-distributed flow and water quality model (INCA- Integrated Catchments Model) has been set up for the whole of the Ganges- Brahmaputra- Meghna (GBM) River system in India and Bangladesh. These massive rivers transport large fluxes of water and nutrients into the Bay of Bengal via the GBM Delta system in Bangladesh. Future climate change will impact these fluxes with changing rainfall, temperature, evapotranspiration and soil moisture deficits being altered in the catchment systems. In this study the INCA model has been used to assess potential impacts of climate change using the UK Met Office Hadley Centre GCM model linked to a regionally coupled model of South East Asia, covering India and Bangladesh. The Hadley Centre model has been pururbed by varying the parameters in the model to generate 17 realisations of future climates. Some of these reflect expected change but others capture the more extreme potential behaviour of future climate conditions. The 17 realisations have been used to drive the INCA Flow and Nitrogen model inorder to generate downstream times series of hydrology and nitrate- nitrogen. The variability of the climates on these fluxes are investigated and and their likley impact on the Bay of Begal Delta considered. Results indicate a slight shift in the monsoon season with increased wet season flows and increased temperatures which alter nutrient fluxes. Societal Importance to Stakeholders The GBM Delta supports one of the most densely populated regions of people living in poverty, who rely on ecosystem services provided by the Delta for survival. These ecosystem services are dependent upon fluxes of water and nutrients. Freshwater for urban, agriculture, and aquaculture requirements are essential to livelihoods. Nutrient loads stimulate estuarine ecosystems, supporting fishing stocks, which contribute significantly the economy of Bangladesh. Thus the societal importance of upstream climate driven change change in Bangladesh are very

  13. Spatial variability and potential impacts of climate change on flood and debris flow hazard zone mapping and implications for risk management

    Directory of Open Access Journals (Sweden)

    H. Staffler

    2008-06-01

    Full Text Available The main goals of this study were to identify the alpine torrent catchments that are sensitive to climatic changes and to assess the robustness of the methods for the elaboration of flood and debris flow hazard zone maps to specific effects of climate changes. In this study, a procedure for the identification and localization of torrent catchments in which the climate scenarios will modify the hazard situation was developed. In two case studies, the impacts of a potential increase of precipitation intensities to the delimited hazard zones were studied.

    The identification and localization of the torrent and river catchments, where unfavourable changes in the hazard situation occur, could eliminate speculative and unnecessary measures against the impacts of climate changes like a general enlargement of hazard zones or a general over dimensioning of protection structures for the whole territory. The results showed a high spatial variability of the sensitivity of catchments to climate changes. In sensitive catchments, the sediment management in alpine torrents will meet future challenges due to a higher rate for sediment removal from retention basins. The case studies showed a remarkable increase of the areas affected by floods and debris flow when considering possible future precipitation intensities in hazard mapping. But, the calculated increase in extent of future hazard zones lay within the uncertainty of the methods used today for the delimitation of the hazard zones. Thus, the consideration of the uncertainties laying in the methods for the elaboration of hazard zone maps in the torrent and river catchments sensitive to climate changes would provide a useful instrument for the consideration of potential future climate conditions. The study demonstrated that weak points in protection structures in future will become more important in risk management activities.

  14. Natural climate variability inferred from cosmogenic isotopes and other geophysical data and its impact on human activity

    International Nuclear Information System (INIS)

    The way how natural climate changes may have influenced anthropological development is discussed. The main characteristics of solar variability are reviewed: (1) as measured in detail over recent decades by instruments on-board artificial satellites; (2) as recorded in historical documents on the time-scale of centuries; and (3) as inferred on millennial time-scales from archived records of the cosmogenically generated isotopes 14C and 10Be. The older, proxy data comprise temperature changes reconstructed from tree ring studies and environmental changes deduced from multi-disciplinary studies of lake sediments. The effects of changes in ocean circulation and the sporadic influence of volcanic activity are also considered briefly. (author)

  15. Variability of contrail formation conditions and the implications for policies to reduce the climate impacts of aviation

    International Nuclear Information System (INIS)

    This paper describes an approach to balance the climate benefits of contrail reduction against the penalties incurred when cruise altitudes are restricted. Altitude restrictions are targeted by selecting, for each 6-h period, the altitude that provides the greatest reduction in contrail for the lowest increase in carbon dioxide emission. Calculations are for western Europe. This paper discusses the variability in contrail formation conditions in the region and presents contrail reductions and carbon dioxide emission increases obtained with this optimised approach, which compare favourably with fixed altitude restrictions. A new method is also developed to estimate contrail fractions within three-dimensional grids. Conclusions discuss potential operational issues associated with a varying altitude restriction policy. (Author)

  16. CITYZEN climate impact studies

    Energy Technology Data Exchange (ETDEWEB)

    Schutz, Martin (ed.)

    2011-07-01

    We have estimated the impact of climate change on the chemical composition of the troposphere due to changes in climate from current climate (2000-2010) looking 40 years ahead (2040-2050). The climate projection has been made by the ECHAM5 model and was followed by chemistry-transport modelling using a global model, Oslo CTM2 (Isaksen et al., 2005; Srvde et al., 2008), and a regional model, EMEP. In this report we focus on carbon monoxide (CO) and surface ozone (O3) which are measures of primary and secondary air pollution. In parallel we have estimated the change in the same air pollutants resulting from changes in emissions over the same time period. (orig.)

  17. Economic impacts of climate change

    OpenAIRE

    Tol, Richard S.J.

    2015-01-01

    Climate change will probably have a limited impact on the economy and human welfare in the 21st century. The initial impacts of climate change may well be positive. In the long run, the negative impacts dominate the positive ones. Negative impacts will be substantially greater in poorer, hotter, and lower-lying countries. Poverty reduction complements greenhouse gas emissions reduction as a means to reduce climate change impacts. Climate change may affect the growth rate of the economy and ma...

  18. The impacts of future climate and carbon dioxide changes on the average and variability of US maize yields under two emission scenarios

    International Nuclear Information System (INIS)

    The United States is the largest producer of maize in the world, a crop for which demand continues to rise rapidly. Past studies have projected that climate change will negatively impact mean maize yields in this region, while at the same time increasing yield variability. However, some have questioned the accuracy of these projections because they are often based on indirect measures of soil moisture, have failed to explicitly capture the potential interactions between temperature and soil moisture availability, and often omit the beneficial effects of elevated carbon dioxide (CO2) on transpiration efficiency. Here we use a new detailed dataset on field-level yields in Iowa, Indiana, and Illinois, along with fine-resolution daily weather data and moisture reconstructions, to evaluate the combined effects of moisture and heat on maize yields in the region. Projected climate change scenarios over this region from a suite of CMIP5 models are then used to assess future impacts and the differences between two contrasting emissions scenarios (RCP 4.5 and RCP 8.5). We show that (i) statistical models which explicitly account for interactions between heat and moisture, which have not been represented in previous empirical models, lead to significant model improvement and significantly higher projected yield variability under warming and drying trends than when accounting for each factor independently; (ii) inclusion of the benefits of elevated CO2 significantly reduces impacts, particularly for yield variability; and (iii) net damages from climate change and CO2 become larger for the higher emission scenario in the latter half of the 21st century, and significantly so by the end of century. (paper)

  19. Effect of climate change on seasonal monsoon in Asia and its impact on the variability of monsoon rainfall in Southeast Asia

    Institute of Scientific and Technical Information of China (English)

    Yen Yi Loo; Lawal Billa; Ajit Singh

    2015-01-01

    Global warming and climate change is one of the most extensively researched and discussed topical issues affecting the environment. Although there are enough historical evidence to support the theory that climate change is a natural phenomenon, many research scientists are widely in agreement that the increase in temperature in the 20th century is anthropologically related. The associated effects are the variability of rainfall and cyclonic patterns that are being observed globally. In Southeast Asia the link between global warming and the seasonal atmospheric flow during the monsoon seasons shows varying degree of fuzziness. This study investigates the impact of climate change on the seasonality of monsoon Asia and its effect on the variability of monsoon rainfall in Southeast Asia. The comparison of decadal variation of precipitation and temperature anomalies before the 1970s found general increases which were mostly varying. But beyond the 1970s, global precipitation anomalous showed increases that almost corresponded with increases in global temperature anomalies for the same period. There are frequent changes and a shift westward of the Indian summer monsoon. Although precipitation is observed to be 70%below normal levels, in some areas the topography affects the intensity of rainfall. These shifting phenomenon of other monsoon season in the region are impacting on the variability of rainfall and the onset of monsoons in Southeast Asia and is predicted to delay for 15 days the onset of the monsoon in the future. The variability of monsoon rainfall in the SEA region is observed to be decadal and the frequency and intensity of intermittent flooding of some areas during the monsoon season have serious consequences on the human, financial, infrastructure and food security of the region.

  20. Impacts of climate change and climate variability on the competitiveness of wheat and beef cattle production in Emerald, north-east Australia.

    Science.gov (United States)

    Howden, S M; McKeon, G M; Meinke, H; Entel, M; Flood, N

    2001-09-01

    Emerald, north-east Queensland, is at the northern margin of the wheat cropping region of Australia. The Emerald region was previously used predominantly for grazing beef cattle; however, cropping has developed in importance over the past 30 years. We use historical climate records (1890-1998) to simulate and compare wheat yields, grass production and live-weight gain (LWG) over time. The cropping expansion from the 1970s to the early 1990s has occurred in a unique period in the 108-year record with the highest average wheat yields, lowest wheat yield variability and the greatest relative productivity of wheat production against grass production. If this window of opportunity is a result of long-term climate variability, then cropping is likely to decline in the region as conditions return to those experienced earlier in the record. If this increase is related to climate change, then cropping is likely to persist in the region with productivity maintained at current levels particularly through the yield-enhancing effects of increased atmospheric CO2 concentrations. However, this persistence will be influenced by the frequencies of El Niño conditions that may increase with global warming. The high relative productivities experienced over the past few decades have probably biased producers' expectations, and applications for drought support need to take into account the longer-term perspective provided by this analysis. Nevertheless, the last 6 years have the lowest simulated mean LWG production on the record. The identification of poor production periods depended on the production element being addressed and the timescale involved. PMID:11697663

  1. Estimation of Land Surface Temperature for the Quantitative Analysis of Land Cover of Lower Areas of Sindh to Assess the Impacts of Climate Variability

    Science.gov (United States)

    Qaisar, Maha

    2016-07-01

    Due to the present land use practices and climate variability, drastic shifts in regional climate and land covers are easily seen and their future reduction and gain are too well predicted. Therefore, there is an increasing need for data on land-cover changes at narrow and broad spatial scales. In this study, a remote sensing-based technique for land-cover-change analysis is applied to the lower Sindh areas for the last decade. Landsat satellite products were analyzed on an alternate yearly basis, from 1990 to 2016. Then Land-cover-change magnitudes were measured and mapped for alternate years. Land Surface Temperature (LST) is one of the critical elements in the natural phenomena of surface energy and water balance at local and global extent. However, LST was computed by using Landsat thermal bands via brightness temperature and a vegetation index. Normalized difference vegetation index (NDVI) was interpreted and maps were achieved. LST reflected NDVI patterns with complexity of vegetation patterns. Along with this, Object Based Image Analysis (OBIA) was done for classifying 5 major classes of water, vegetation, urban, marshy lands and barren lands with significant map layouts. Pakistan Meteorological Department provided the climate data in which rainfall, temperature and air temperature are included. Once the LST and OBIA are performed, overlay analysis was done to correlate the results of LST with OBIA and LST with meteorological data to ascertain the changes in land covers due to increasing centigrade of LST. However, satellite derived LST was also correlated with climate data for environmental analysis and to estimate Land Surface Temperature for assessing the inverse impacts of climate variability. This study's results demonstrate the land-cover changes in Lower Areas of Sindh including the Indus Delta mostly involve variations in land-cover conditions due to inter-annual climatic variability and temporary shifts in seasonality. However it is too concluded

  2. Impact of Late Holocene climate variability and anthropogenic activities on Biscayne Bay (Florida, U.S.A.): evidence from diatoms

    Science.gov (United States)

    Wachnicka, Anna; Gaiser, Evelyn; Wingard, Lynn; Briceño, Henry; Harlem, Peter

    2013-01-01

    Shallow marine ecosystems are experiencing significant environmental alterations as a result of changing climate and increasing human activities along coasts. Intensive urbanization of the southeast Florida coast and intensification of climate change over the last few centuries changed the character of coastal ecosystems in the semi-enclosed Biscayne Bay, Florida. In order to develop management policies for the Bay, it is vital to obtain reliable scientific evidence of past ecological conditions. The long-term records of subfossil diatoms obtained from No Name Bank and Featherbed Bank in the Central Biscayne Bay, and from the Card Sound Bank in the neighboring Card Sound, were used to study the magnitude of the environmental change caused by climate variability and water management over the last ~ 600 yr. Analyses of these records revealed that the major shifts in the diatom assemblage structures at No Name Bank occurred in 1956, at Featherbed Bank in 1966, and at Card Sound Bank in 1957. Smaller magnitude shifts were also recorded at Featherbed Bank in 1893, 1942, 1974 and 1983. Most of these changes coincided with severe drought periods that developed during the cold phases of El Niño Southern Oscillation (ENSO), Atlantic Multidecadal Oscillation (AMO) and Pacific Decadal Oscillation (PDO), or when AMO was in warm phase and PDO was in the cold phase. Only the 1983 change coincided with an unusually wet period that developed during the warm phases of ENSO and PDO. Quantitative reconstructions of salinity using the weighted averaging partial least squares (WA-PLS) diatom-based salinity model revealed a gradual increase in salinity at the three coring locations over the last ~ 600 yr, which was primarily caused by continuously rising sea level and in the last several decades also by the reduction of the amount of freshwater inflow from the mainland. Concentration of sediment total nitrogen (TN), total phosphorus (TP) and total organic carbon (TOC) increased in the

  3. Marine reserves help preserve genetic diversity after impacts derived from climate variability: Lessons from the pink abalone in Baja California

    Directory of Open Access Journals (Sweden)

    Adrián Munguía-Vega

    2015-07-01

    Full Text Available Genetic diversity is crucial for the adaptation of exploited species like the pink abalone (Haliotis corrugata, faced with threats from climate change, overfishing and impacts associated with aquaculture production. While marine reserves are commonly used to mitigate risks to marine populations, the duration, size, location and larval connectivity needed for a reserve to help conserve genetic resources is still poorly understood. Here, we examine the effects of fishing, reserves, and restocking on the genetic diversity of 10 populations from central Baja California, Mexico, and Southern California, USA. We demonstrate that each population shows characteristic genetic signatures according to recent management decisions. We found high allelic diversity, particularly rare alleles, a larger effective population size and a lack of a recent genetic bottleneck in pink abalones within a small (0.8 km2, recently established (5 years reserve in Baja California, compared to other fished sites after a climatic bottleneck. Higher diversity may result from the presence of older animals in the reserve. Due to its location, the reserve may also act as an important hub connecting distant populations via larval dispersal. In contrast, a population from California showed genetic isolation, loss of allelic diversity and high relatedness, consistent with the collapse of fisheries in the 1990s and their lack of recovery thereafter. In addition, a fished area in Baja California with a history of restocking for over a decade showed an increase in frequency of related individuals and high genetic differentiation from nearby sites that were consistent with the production of larvae from a few adults in the laboratory. A network of strategically placed small marine reserves that considers ocean circulation patterns could help to maintain genetic diversity and connectivity of exploited populations.

  4. Climate impacts on Flanders' fields

    Science.gov (United States)

    Gobin, Anne

    2010-05-01

    During the past decade Belgium has experienced more monthly extremes than in any other decade since observations started in 1833. According to Global Circulation Model predictions, the frequency and magnitude of extreme weather events are likely to increase with climate change. Not only the frequency and magnitude of meteorological events but also their timing in relation to crop development and the physical environment will determine their impact. The implications of extreme weather events are demonstrated for the year with the lowest yields in the past decade for winter wheat (2001), winter barley (2003), potatoes (2006) and sugar beet (1998) in the agricultural regions of Flanders. Water stress, both drought and flooding, and heat stress seem the major factors that influence arable yields in Flanders. The unfavourable weather conditions during the growth season may be further aggravated by the physical environment. A bad year for one arable crop is not necessarily a bad year for another arable crop such that diversification within one farm may be a good strategy to cope with weather variability. Based on analysis of historical yield and weather data, a process-based dynamic vegetation model was designed to integrate the effects of crop management, weather and physical environment on crop growth. The model operates at a regional scale commensurate with regional climate models and capable of both capturing weather and climate variability impacts. Pronounced yield losses mainly due to water shortages and heat stress occur for all climate change scenarios, to a lesser extent in the case of winter cereals on loam soils. Root crops such as potatoes and sugar beet will experience increased drought stress particularly when the probability rises that sensitive crop development stages coincide with dry spells. This may be aggravated when wet springs cause water logging in the field and delay planting dates. Despite lower summer precipitation predictions for the future

  5. Prioritizing Global Observations Along Essential Climate Variables

    Science.gov (United States)

    Bojinski, Stephan; Richter, Carolin

    2010-12-01

    The Global Climate Observing System (GCOS) Secretariat, housed within the World Meteorological Organization, released in August 2010 updated guidance for priority actions worldwide in support of observations of GCOS Essential Climate Variables (ECVs). This guidance states that full achievement of the recommendations in the 2010 Implementation Plan for the Global Observing System for Climate in Support of the UNFCCC (http://www.wmo.int/pages/prog/gcos/Publications/gcos­138.pdf) is required to ensure that countries are able to understand and predict climate change and its impacts and manage their response throughout the 21st century and beyond. GCOS is sponsored by the United Nations and the International Council for Science (ICSU) and is an internationally coordinated network of observing systems and a program of activities that support and improve the network, which is designed to meet evolving national and international requirements for climate observations. One of the main objectives of GCOS is to sustain observations into the future to allow evaluation of how climate is changing, so that informed decisions can be made on prevention, mitigation, and adaptation strategies. GCOS priorities are based on the belief that observations are crucial to supporting the research needed to refine understanding of the climate system and its changes, to initialize predictions on time scales out to decades, and to develop the models used to make these predictions and longer­term scenario-based projections. Observations are also needed to assess social and economic vulnerabilities and to support related actions needed across a broad range of societal sectors by underpinning emerging climate services.

  6. Impacts of Climate Change on Brazilian Agriculture

    OpenAIRE

    Assad, Eduardo; Pinto, Hilton S.; Nassar, Andre; Harfuch, Leila; Freitas, Saulo; Farinelli, Barbara; Lundell, Mark; Erick C.M. Fernandes

    2013-01-01

    This report evaluates the requirements for an assessment of climate change impacts on agriculture to guide policy makers on investment priorities and phasing. Because agriculture is vital for national food security and is a strong contributor to Brazil's GDP growth, there is growing concern that Brazilian agriculture is increasingly vulnerable to climate variability and change. To meet nat...

  7. Temporal variability of particulate organic carbon in the lower Changjiang (Yangtze River) in the post-Three Gorges Dam period: Links to anthropogenic and climate impacts

    Science.gov (United States)

    Wu, Ying; Bao, Hongyan; Yu, Hao; Zhang, Jing; Kattner, Gerhard

    2015-11-01

    Suspended particles from the lower Changjiang were collected monthly from 2003 to 2011, which corresponds to the three construction periods of the Three Gorges Dam. Organic carbon (%OC), organic carbon to total nitrogen molar ratio, stable carbon isotope, and terrestrial biomarkers were examined. Rating curve studies were applied for the temporal trend analysis. The composition of particulate lignin phenols exhibited clear annual and periodic variations but only minor seasonal changes. Lignin phenol ratios (vanillyl/syringyl and cinnamyl/vanillyl) indicated that the terrigenous organic matter (OM) was primarily composed of woody and nonwoody tissue derived from angiosperm plants. The low-lignin phenol yields (Λ8) in combination with higher acid to aldehyde ratios reflected a substantial contribution from soil OM to the particle samples or modifications during river transport. The temporal shift of the lignin phenol vegetation index with the sediment load during the flood seasons revealed particulate organic matter (POM) erosion from soils and the impact of hydrodynamic processes. The dam operations affected the seasonal variability of terrigenous OM fluxes, although the covariation of lignin and sediment loads with discharged water implies that unseasonal extreme conditions and climate change most likely had larger influences, because decreases in the sediment load and lignin flux alter the structure and composition of particulate OM (POM) on interannual time scales, indicating that they may be driven by climate variability. The modification of the composition and structure of POM will have significant impacts on regional carbon cycles and marine ecosystems.

  8. Impacts of Present and Future Climate Variability and Change on Agriculture and Forestry in the Arid and Semi-Arid Tropics

    International Nuclear Information System (INIS)

    The arid and semi-arid regions account for approximately 30% of the world total area and are inhabited by approximately 20% of the total world population. Issues of present and future climate variability and change on agriculture and forestry in the arid and semi-arid tropics of the world were examined and discussion under each of these issues had been presented separately for Asia, Africa and Latin America. Several countries in tropical Asia have reported increasing surface temperature trends in recent decades. Although, there is no definite trend discernible in the long-term mean for precipitation for the tropical Asian region, many countries have shown a decreasing trend in rainfall in the past three decades. African rainfall has changed substantially over the last 60 yr and a number of theoretical, modelling and empirical analyses have suggested that noticeable changes in the frequency and intensity of extreme events, including floods may occur when there are only small changes in climate. Climate in Latin America is affected by the El Nino-southern oscillation (ENSO) phases and there is a close relationship between the increase and decrease of rainfall depending upon the warm or cold phases of the phenomenon. Over land regions of Asia, the projected area-averaged annual mean warming is likely to be 1.6 ± 0.2C in the 2020s, 3.1 ± 0.3C in the 2050s, and 4.6 ± 0.4C in the 2080s and the models show high uncertainty in projections of future winter and summer precipitation. Future annual warming across Africa is projected to range from 0.2C per decade to more than 0.5C per decade, while future changes in mean seasonal rainfall in Africa are less well defined. In Latin America, projections indicate a slight increase in temperature and changes in precipitation. Impacts of climate variability and changes are discussed with suitable examples. Agricultural productivity in tropical Asia is sensitive not only to temperature increases, but also to changes in the nature

  9. Advances in Understanding Decadal Climate Variability

    Science.gov (United States)

    Busalacchi, Antonio J.

    1999-01-01

    Recently, a joint Brazil-France-U.S. program, known as PIRATA (Pilot Research moored Array in the Tropical Atlantic), was proposed to begin the deployment of moored measurement platforms in the tropical Atlantic in order to enhance the existing observational data base and subsequent understanding of the processes by which the ocean and atmosphere couple in key regions of the tropical Atlantic Ocean. Empirical studies have suggested that there are strong relationships between tropical Atlantic upper ocean variability, SST, ocean-atmosphere coupling and regional climate variability. During the early 1980's a coordinated set of surface wind, subsurface thermal structure, and subsurface current observations were obtained as part of the U.S.-France SEQUAL-FOCAL process experiment designed to observe the seasonal response of the tropical Atlantic Ocean to surface forcing. Since that time, however, the observational data base for the tropical Atlantic Ocean has disintegrated to a few ship-tracks measuring ocean temperatures and a small collection of tide gauge stations measuring sea level. A more comprehensive set of observations, modeling and empirical studies is now in order to make progress on understanding the regional climate variability. The proposed PIRATA program will use mooring platforms similar to the tropical Pacific Ocean TAO array to measure surface fluxes of momentum and heat and the corresponding changes in the upper ocean thermal structure. It is anticipated that the oceanic data from this monitoring array will also be used in a predictive mode for initialization studies of regional coupled climate models. Of particular interest are zonal and meridional modes of ocean-atmosphere variability within the tropical Atlantic basin that have significant impacts on the regional climate of the bordering continents.

  10. Seasonal Variability of Wind Climate in Hungary

    OpenAIRE

    PÉLINÉ NÉMETH, Csilla; RADICS, Kornélia; Bartholy, Judit

    2011-01-01

    One of the most important effects of climate variability and climate change may comefrom changes in the intensity and frequency of climatic extremes. Responding to the need of newclimatologic analyses, complex wind field research was carried out to study and provide reliableinformation about the state and variability of wind climate in Hungary. First of all, special attentionwas paid on creation of a high quality, homogeneous data series. The research is based on 36-yearlong(1975–2010) wind d...

  11. Impact of severe climate variability on lion home range and movement patterns in the Amboseli ecosystem, Kenya

    Directory of Open Access Journals (Sweden)

    J.H. Tuqa

    2014-12-01

    Full Text Available In this study, we were interested in understanding if droughts influence the home range of predators such as lions, and if it does, in what ways the droughts influenced lions to adjust their home range, in response to prey availability. We monitored movements of ten lions fitted with GPS-GSM collars in order to analyze their home range and movement patterns over a six year period (2007–2012. We assessed the impact of a severe drought on the lion home range and movement patterns in the Amboseli ecosystem. There was a strong positive correlation between the home range size and distance moved in 24 h before and during the drought (2007–2009, while after the drought there was a significant negative correlation. A weak positive correlation was evident between the lion home range and rainfall amounts (2010–2012. The male and female home ranges varied over the study period. The home range size and movement patterns coincided with permanent swamps and areas of high prey density inside the protected area. Over the course of the dry season and following the drought, the ranges initially shrank and then expanded in response to decreasing prey densities. The lions spent considerable time outside the park boundaries, particularly after severe the drought. We conclude that under conditions of fragmented habitats, severe climate conditions create new challenges for lion conservation due to effects on prey availability and subsequent influences on carnivore species ranging patterns. Stochastic weather patterns can force wide-ranging species beyond current reserve boundaries, into areas where there will be greater conflicts with humans.

  12. Interactions of Mean Climate Change and Climate Variability on Food Security Extremes

    Science.gov (United States)

    Ruane, Alexander C.; McDermid, Sonali; Mavromatis, Theodoros; Hudson, Nicholas; Morales, Monica; Simmons, John; Prabodha, Agalawatte; Ahmad, Ashfaq; Ahmad, Shakeel; Ahuja, Laj R.

    2015-01-01

    Recognizing that climate change will affect agricultural systems both through mean changes and through shifts in climate variability and associated extreme events, we present preliminary analyses of climate impacts from a network of 1137 crop modeling sites contributed to the AgMIP Coordinated Climate-Crop Modeling Project (C3MP). At each site sensitivity tests were run according to a common protocol, which enables the fitting of crop model emulators across a range of carbon dioxide, temperature, and water (CTW) changes. C3MP can elucidate several aspects of these changes and quantify crop responses across a wide diversity of farming systems. Here we test the hypothesis that climate change and variability interact in three main ways. First, mean climate changes can affect yields across an entire time period. Second, extreme events (when they do occur) may be more sensitive to climate changes than a year with normal climate. Third, mean climate changes can alter the likelihood of climate extremes, leading to more frequent seasons with anomalies outside of the expected conditions for which management was designed. In this way, shifts in climate variability can result in an increase or reduction of mean yield, as extreme climate events tend to have lower yield than years with normal climate.C3MP maize simulations across 126 farms reveal a clear indication and quantification (as response functions) of mean climate impacts on mean yield and clearly show that mean climate changes will directly affect the variability of yield. Yield reductions from increased climate variability are not as clear as crop models tend to be less sensitive to dangers on the cool and wet extremes of climate variability, likely underestimating losses from water-logging, floods, and frosts.

  13. Impacts of long- and short-term climate variability on terrestrial biogenic emissions and their influence on the remote tropical troposphere

    Science.gov (United States)

    Monks, S. A.; Arnold, S.; Guenther, A. B.; Emmons, L. K.; Carpenter, L.; Read, K.

    2013-12-01

    Terrestrial vegetation emits a wide range of biogenic volatile organic compounds (BVOC) into the atmosphere (~1150 TgC/yr), which accounts for ~90% of total VOC surface emissions. Emissions of BVOC are largely dependent on environmental factors such as sunlight and temperature, which makes them sensitive to both long-term and short-term changes in the climate system. ENSO is well-known to have global impacts on temperature and precipitation, and therefore has the potential to impact regional BVOC emissions on inter-annual time-scales. In addition to this, increased global mean temperatures and atmospheric carbon dioxide (CO2) concentrations over the past few decades may also have affected BVOC emissions. Once in the atmosphere, these compounds have the ability to influence global and regional atmospheric chemistry and climate through impacts on the hydroxyl radical, ozone, particulate matter and methane lifetime. We use the NCAR Community Land Model (CLM) coupled to the Model of Emissions of Gases and Aerosols from Nature (MEGANv2) to investigate both long-term changes and inter-annual variability of BVOC emissions over a 50-year period at regional and global spatial-scales. This is done by considering the impacts of increasing temperatures and CO2 concentrations on long-term emissions of BVOC separately, in addition to using the Multivariate ENSO Index (MEI) to investigate the regional response in emissions due to natural ENSO variability. Global composites of ENSO-positive and ENSO-negative phase emissions are then used to drive global atmospheric chemistry simulations using the NCAR Community Earth System Model (CESM). Through comparisons with 6 years of measurements from the Cape Verde observatory in the tropical Atlantic Ocean, we explore the role of inter-annual variability in terrestrial biogenic emissions in controlling the observed variability in methanol, acetone and acetaldehyde in the remote tropical atmosphere. By accounting for inter-annual changes in

  14. Societal Vulnerability to Climate Change and Variability

    International Nuclear Information System (INIS)

    Institutions in many wealthy industrialised countries are robust and their societies appear to be relatively well insulated against the impacts of climate variability, economic problems elsewhere and so on. However, many countries are not in this position, and there is a growing group of humanity which is not benefiting from the apparent global adaptive trends. Worst case scenarios reinforce the impact of this uneven distribution of adaptive capacity, both between and within countries. Nevertheless, at the broad global scale human societies are strongly adaptive and not threatened by climate change for many decades. At the local level the picture is quite different and the survival of some populations at their present locations is in doubt. In the absence of abatement, the longer term outlook is highly uncertain. Adaptation research needs to begin with an understanding of social and economic vulnerability. It requires a different approach to the traditional IPCC impacts assessment, as human behaviour, institutional capacity and culture are more important than biophysical impacts. This is consistent with the intellectual history of the IPCC which has gradually embraced an increasing range of disciplines. 32 refs

  15. Detecting the long-term impacts from climate variability and increasing water consumption on runoff in the Krishna river basin (India

    Directory of Open Access Journals (Sweden)

    L. M. Bouwer

    2006-01-01

    Full Text Available Variations in climate, land-use and water consumption can have profound effects on river runoff. There is an increasing demand to study these factors at the regional to river basin-scale since these effects will particularly affect water resources management at this level. This paper presents a method that can help to differentiate between the effects of man-made hydrological developments and climate variability (including both natural variability and anthropogenic climate change at the basin scale. We show and explain the relation between climate, water consumption and changes in runoff for the Krishna river basin in central India. River runoff variability due to observed climate variability and increased water consumption for irrigation and hydropower is simulated for the last 100 years (1901–2000 using the STREAM water balance model. Annual runoff under climate variability is shown to vary only by about 14–34 millimetres (6–15%. It appears that reservoir construction after 1960 and increasing water consumption has caused a persistent decrease in annual river runoff of up to approximately 123 mm (61%. Variation in runoff under climate variability only would have decreased over the period under study, but we estimate that increasing water consumption has caused runoff variability that is three times higher.

  16. Impact of climate variability on terrestrial environment in Western Europe between 45 and 9 kyr cal. BP: vegetation dynamics recorded by the Bergsee Lake (Black Forest, Germany).

    Science.gov (United States)

    Duprat-Oualid, Fanny; Begeot, Carole; Rius, Damien; Millet, Laurent; Magny, Michel

    2016-04-01

    changes at millennial/pluri-millennial scale. The well-known afforestation of the Late-Glacial interstadial and the Holocene (with pine and hazel-dominated forests respectively) are recorded. Our results also reveal a three-phase sequence in the Last-Glacial. The persistence of very cold conditions between 24 and 30 kyr cal. BP favored a drastic steppe grassland. In contrast, trees proportion increased during the two other periods (14.7-24 and 30-45 kyr cal. BP) in correlation with a relative favorable climate. Second, the respons of vegetation to centennial scale climatic events is characterized by the successive rapid establishment of two different landscapes. GS are dominated by steppic taxa (Artemisia, Helianthemum), whereas more or less complete ecological successions Juniperus-Betula-Pinus seem to occur for most GIs when edaphic conditions became more favorable. Therefore, we suggest a global forcing defined by the strong impact of the climate variability on vegetation changes. We also propose the contribution of local characteristics (latitude, topography) which favored flora migration and long distance pollen inputs from refuge areas. Heiri O., Koinig K.A., Spötl C., Barrett S, Brauer A., Drescher-Schneider R., Gaar D., Ivy-Ochs S., Kerschner H., Luetscher M., Moran A., Nicolussi K., Preusser F., Schmidt R., Schoeneich P., Schwörer C., Sprafke T., Terhorst B., Tinner W. -2014- "Palaeoclimate records 60-8 ka in the Austrian and Swiss Alps and their forelands", Quaternary Science Review, 106 : 186-205.

  17. Impact of climate, vegetation, soil and crop management variables on multi-year ISBA-A-gs simulations of evapotranspiration over a Mediterranean crop site

    Directory of Open Access Journals (Sweden)

    S. Garrigues

    2015-02-01

    Full Text Available Generic land surface models are generally driven by large-scale forcing datasets to describe the climate, the surface characteristics (soil texture, vegetation dynamic and the cropland management (irrigation. This paper investigates the errors in these forcing variables and their impacts on the evapotranspiration (ET simulated from the Interactions between Soil, Biosphere, and Atmosphere (ISBA-A-gs land surface model over a 12 year Mediterranean crop succession. We evaluate the forcing datasets used in the standard implementation of ISBA over France where the model is driven by the SAFRAN high spatial resolution atmospheric reanalysis, the Leaf Area Index (LAI cycles derived from the Ecoclimap-II land surface parameter database and the soil texture derived from the French soil database. For climate, we focus on the radiations and rainfall variables and we test additional datasets which includes the ERA-Interim low spatial resolution reanalysis, the Global Precipitation Climatology Centre dataset (GPCC and the MeteoSat Second Generation (MSG satellite estimate of downwelling shortwave radiations. The methodology consists in comparing the simulation achieved using large-scale forcing datasets with the simulation achieved using local observations for each forcing variable. The relative impacts of the forcing variables on simulated ET are compared with each other and with the model uncertainties triggered by errors in soil parameters. LAI and the lack of irrigation in the simulation generate the largest mean deviations in ET between the large-scale and the local-scale simulations (equivalent to 24 and 19 months of ET over 12 yr. The climate induces smaller mean deviations equivalent to 7–8 months of ET over 12 yr. The soil texture has the lowest impact (equivalent to 3 months of ET. However, the impact of errors in the forcing variables is smaller than the impact triggered by errors in the soil parameters (equivalent to 27 months of ET. The

  18. Variability of the earth's climate

    International Nuclear Information System (INIS)

    In this paper, the global evolution of the Earth's climate since the Precambrian is described and the reconstruction of the last major oscillations generally referred to as the last climatic cycles which occurred during the Quarternary is presented: isotope geochemistry, micropaleontological transfer functions; ice volume and sea level, temperatures, deep water circulation of the last climatic cycle

  19. Multi-Wheat-Model Ensemble Responses to Interannual Climate Variability

    Science.gov (United States)

    Ruane, Alex C.; Hudson, Nicholas I.; Asseng, Senthold; Camarrano, Davide; Ewert, Frank; Martre, Pierre; Boote, Kenneth J.; Thorburn, Peter J.; Aggarwal, Pramod K.; Angulo, Carlos

    2016-01-01

    We compare 27 wheat models' yield responses to interannual climate variability, analyzed at locations in Argentina, Australia, India, and The Netherlands as part of the Agricultural Model Intercomparison and Improvement Project (AgMIP) Wheat Pilot. Each model simulated 1981e2010 grain yield, and we evaluate results against the interannual variability of growing season temperature, precipitation, and solar radiation. The amount of information used for calibration has only a minor effect on most models' climate response, and even small multi-model ensembles prove beneficial. Wheat model clusters reveal common characteristics of yield response to climate; however models rarely share the same cluster at all four sites indicating substantial independence. Only a weak relationship (R2 0.24) was found between the models' sensitivities to interannual temperature variability and their response to long-termwarming, suggesting that additional processes differentiate climate change impacts from observed climate variability analogs and motivating continuing analysis and model development efforts.

  20. Future Climate Variability and Watershed Response in Southern California

    OpenAIRE

    Lopez, Sonya Rita

    2012-01-01

    The current work focuses on assessing the impacts of future climate variability on water resources in southern California. Specifically, this dissertation work includes: (1) developing archetypal watersheds and climate scenarios to obtain regional changes to hydrology and sediment transport and (2) developing a statistical downscaling approach that considers regional climate heterogeneity (commonly neglected in downscaling methods) and using this data to drive hydrologic models. The archetypa...

  1. Tropical North Africa hydro climate variability

    International Nuclear Information System (INIS)

    NCEP/NCAR data are used to study the modulating circulations of the hydro climate of tropical North Africa. Wavelet analysis is used to identify modes of variability of stream flows within the region. Ocean-atmosphere circulation composites are considered to unravel the mechanisms for swing of stream flows. The one of the main finding of the study reveals that hydro climate variability swings within ENSO and decadal timescale. Pacific and Atlantic sea surface temperatures control the hydro climate mode of variability. Associated to Pacific sea surface temperature, the Atlantic Walker Circulation modulates the hydro climate swing of tropical North Africa. The detail result will be discussed.(Author)

  2. Climate variability and change: a perspective from the oceania region

    Science.gov (United States)

    Beer, Tom

    2014-12-01

    This brief review identifies seven key science questions in relation to climate variability and change and examines recent research within the Australian and Pacific context: 1. How do the key processes controlling climate variability and predictability operate? 2. What are the nature and causes of regional climate anomalies, past variations in regional climate and extreme weather events and how will they change in the future? 3. How can we provide improved seasonal-to-interannual climate predictions? 4. What are the best projection methods? 5. What are the sea-level changes now and in the future; and how will these impact the coasts? 6. How to have significant benefits on climate service delivery and environmental management? 7. What are the best methods for assessing climate change risks, vulnerability and adaptation options?

  3. Climate variability and climate change in Mexico: A review

    OpenAIRE

    E. JÁUREGUI

    1997-01-01

    A review of research on climate variability, fluctuations and climate change in Mexico is presented. Earlier approaches include different time scales from paleoclimatic to historical and instrumental. The nature and causes of variability in Mexico have been attributed to large-scale southward/northward shifts of the mid-latitude major circulation and more recently to the ENSO cycle. Global greenhouse warming has become a major environmental issue and has spawned a large number of climate-chan...

  4. Climatic change and impacts: a general introduction

    International Nuclear Information System (INIS)

    These proceedings are divided into six parts containing 29 technical papers. 1. An Overview of the Climatic System, 2. Past climate Changes, 3. Climate Processes and Climate Modelling, 4. Greenhouse Gas Induced Climate Change, 5. Climatic Impacts, 6. STUDENTS' PAPERS

  5. CLIMATE CHANGE, VARIABILITY AND SUSTAINABLE AGRICULTURE IN ZIMBABWE'S RURAL COMMUNITIES

    Directory of Open Access Journals (Sweden)

    Gukurume Simbarashe

    2013-02-01

    Full Text Available This article explores the impact of climate change and variability on agricultural productivity in the communal area of Bikita. The article further examines the adaptation and mitigation strategies devised by farmers to deal with the vagaries of climate change and variability. The sustainability of these is also interrogated in this article. This study juxtaposed qualitative and quantitative methodologies albeit with more bias on the former. A total of 40 farmers were sampled for unstructured interviews and focus group discussions. This article argues that the adverse impacts of climate change and variability are felt heavily by the poor communal farmers who are directly dependent on agriculture for livelihood. From the study, some of the widely reported signs of climate variability in Bikita included late and unpredictable rains, high temperatures (heat waves, successive drought, shortening rainfall seasons and seasonal changes in the timing of rainfall. The paper argues that climate change has compounded the vulnerability of peasant farmers in the drought - prone district of Bikita plunging them into food insecurity and abject poverty. It emerged in the study that some of effects of climate variability felt by communal farmers in Bikita included failure of crops, death of livestock and low crop yields, all of which have led to declining agricultural productivity. Findings in this study however established that communal farmers have not been passive victims of the vagaries of climate change and variability. They have rationally responded to it through various adaptation and mitigation strategies both individually and collectively.

  6. Climate variability and Port wine quality

    Science.gov (United States)

    Gouveia, Celia; Liberato, Margarida L. R.; Trigo, Ricardo M.; Dacamara, Carlos

    2010-05-01

    ), suggesting that this type of analysis may be used in developing a tool that may help anticipating a vintage year, based on already available seasonal climate outlooks. Célia Gouveia and Ricardo M. Trigo. "Influence of climate variability on wheat production in Portugal". GeoENV2006- 6th International Conference on Geostatistics for Environmental Applications, Rhodes, October, 25-27, 2006 Miranda, P.M.A., F. Coelho, A. R. Tomé, M. A Valente., A. Carvalho, C. Pires, H. O. Pires, V. C. Cabrinha and C. Ramalho (2002) "20th Century Portuguese Climate and Climate Scenarios", in Santos, F.D., K Forbes and R. Moita (eds) Climate Change in Portugal: Scenarios, Impacts and Adptation Measures", 27-83. Gradiva

  7. Food Price Volatility and Decadal Climate Variability

    Science.gov (United States)

    Brown, M. E.

    2013-12-01

    The agriculture system is under pressure to increase production every year as global population expands and more people move from a diet mostly made up of grains, to one with more meat, dairy and processed foods. Weather shocks and large changes in international commodity prices in the last decade have increased pressure on local food prices. This paper will review several studies that link climate variability as measured with satellite remote sensing to food price dynamics in 36 developing countries where local monthly food price data is available. The focus of the research is to understand how weather and climate, as measured by variations in the growing season using satellite remote sensing, has affected agricultural production, food prices and access to food in agricultural societies. Economies are vulnerable to extreme weather at multiple levels. Subsistence small holders who hold livestock and consume much of the food they produce are vulnerable to food production variability. The broader society, however, is also vulnerable to extreme weather because of the secondary effects on market functioning, resource availability, and large-scale impacts on employment in trading, trucking and wage labor that are caused by weather-related shocks. Food price variability captures many of these broad impacts and can be used to diagnose weather-related vulnerability across multiple sectors. The paper will trace these connections using market-level data and analysis. The context of the analysis is the humanitarian aid community, using the guidance of the USAID Famine Early Warning Systems Network and the United Nation's World Food Program in their response to food security crises. These organizations have worked over the past three decades to provide baseline information on food production through satellite remote sensing data and agricultural yield models, as well as assessments of food access through a food price database. Econometric models and spatial analysis are used

  8. Life in the Frequency Domain: the Biological Impacts of Changes in Climate Variability at Multiple Time Scales.

    Science.gov (United States)

    Dillon, Michael E; Woods, H Arthur; Wang, George; Fey, Samuel B; Vasseur, David A; Telemeco, Rory S; Marshall, Katie; Pincebourde, Sylvain

    2016-07-01

    Over the last few decades, biologists have made substantial progress in understanding relationships between changing climates and organism performance. Much of this work has focused on temperature because it is the best kept of climatic records, in many locations it is predicted to keep rising into the future, and it has profound effects on the physiology, performance, and ecology of organisms, especially ectothermic organisms which make up the vast majority of life on Earth. Nevertheless, much of the existing literature on temperature-organism interactions relies on mean temperatures. In reality, most organisms do not directly experience mean temperatures; rather, they experience variation in temperature over many time scales, from seconds to years. We propose to shift the focus more directly on patterns of temperature variation, rather than on means per se, and present a framework both for analyzing temporal patterns of temperature variation and for incorporating those patterns into predictions about organismal biology. In particular, we advocate using the Fourier transform to decompose temperature time series into their component sinusoids, thus allowing transformations between the time and frequency domains. This approach provides (1) standardized ways of visualizing the contributions that different frequencies make to total temporal variation; (2) the ability to assess how patterns of temperature variation have changed over the past half century and may change into the future; and (3) clear approaches to manipulating temporal time series to ask "what if" questions about the potential effects of future climates. We first summarize global patterns of change in temperature variation over the past 40 years; we find meaningful changes in variation at the half day to yearly times scales. We then demonstrate the utility of the Fourier framework by exploring how power added to different frequencies alters the overall incidence of long-term waves of high and low

  9. Climatic impact of volcanic eruptions

    Science.gov (United States)

    Rampino, Michael R.

    1991-01-01

    Studies have attempted to 'isolate' the volcanic signal in noisy temperature data. This assumes that it is possible to isolate a distinct volcanic signal in a record that may have a combination of forcings (ENSO, solar variability, random fluctuations, volcanism) that all interact. The key to discovering the greatest effects of volcanoes on short-term climate may be to concentrate on temperatures in regions where the effects of aerosol clouds may be amplified by perturbed atmospheric circulation patterns. This is especially true in subpolar and midlatitude areas affected by changes in the position of the polar front. Such climatic perturbation can be detected in proxy evidence such as decrease in tree-ring widths and frost rings, changes in the treeline, weather anomalies, severity of sea-ice in polar and subpolar regions, and poor grain yields and crop failures. In low latitudes, sudden temperature drops were correlated with the passage overhead of the volcanic dust cloud (Stothers, 1984). For some eruptions, such as Tambora, 1815, these kinds of proxy and anectdotal information were summarized in great detail in a number of papers and books (e.g., Post, 1978; Stothers, 1984; Stommel and Stommel, 1986; C. R. Harrington, in press). These studies lead to the general conclusion that regional effects on climate, sometimes quite severe, may be the major impact of large historical volcanic aerosol clouds.

  10. Assessing Climate Change Impacts: Agriculture

    OpenAIRE

    Bosello, Francesco; Zhang, Jian

    2005-01-01

    The economy-wide implications of climate change on agricultural sectors in 2050 are estimated using a static computable general equilibrium model. Peculiar to this exercise is the coupling of the economic model with a climatic model forecasting temperature increase in the relevant year and with a crop-growth model estimating climate change impact on cereal productivity. The main results of the study point out on the one hand the limited influence of climate change on world food supply and wel...

  11. Assessing the Biophysical Impact and Financial Viability of Soil Management Technologies Under Variable Climate in Cabo Verde Drylands

    NARCIS (Netherlands)

    Baptista, Isaurinda; Irvine, Brian; Fleskens, Luuk; Geissen, Violette; Ritsema, Coen

    2016-01-01

    Field trials have demonstrated the potential of soil conservation technologies but have also shown significant spatial-temporal yield variability. This study considers the Pan-European Soil Erosion Risk Assessment - Desertification Mitigation Cost-Effectiveness modelling approach to capture a gre

  12. THE VARIABILITY OF RAINFALL REGIME, INDUCED BY CLIMATE CHANGES, IN DOLJ COUNTY AND IT IMPACT ON THE ENVIRONMENT

    Directory of Open Access Journals (Sweden)

    MIREA ADRIAN

    2016-03-01

    Full Text Available Climate change is now widely recognized as an actual fact: temperatures are rising, rainfall patterns are changing, glaciers and snow melts, and average global sea level rises. We expect these changes to continue and extreme weather conditions that lead to risks like floods and droughts to become more frequent and increase their intensity. Drought and phenomena associated with it, namely aridization (lowering excessive groundwater level and desertification (reduced area of ground covered by vegetation and a considerable depletion and soil erosion represents, after pollution, the second largest problem facing humanity, currently affecting all regions of the globe. In Dolj County, the area between Calafat-Poiana Mare-Sadova-Bechet- Dăbuleni and the Danube, covering about 104 600 hectares, represents the most typical aspect of semi-arid zone with accents of aridity and even desertification in Romania, the phenomenon being favored by the presence of sandy soils. In Dolj County, there may be seen an important manifestation of climate change on the rainfall regime: increasing linear trend especially in the northern part of the county compared to the extreme south of the country, where atmospheric circulation interaction with local relief conditions,often causes diminishing rainfall.

  13. Impact of climate, vegetation, soil and crop management variables on multi-year ISBA-A-gs simulations of evapotranspiration over a Mediterranean crop site

    Science.gov (United States)

    Garrigues, S.; Olioso, A.; Carrer, D.; Decharme, B.; Calvet, J.-C.; Martin, E.; Moulin, S.; Marloie, O.

    2015-10-01

    Generic land surface models are generally driven by large-scale data sets to describe the climate, the soil properties, the vegetation dynamic and the cropland management (irrigation). This paper investigates the uncertainties in these drivers and their impacts on the evapotranspiration (ET) simulated from the Interactions between Soil, Biosphere, and Atmosphere (ISBA-A-gs) land surface model over a 12-year Mediterranean crop succession. We evaluate the forcing data sets used in the standard implementation of ISBA over France where the model is driven by the SAFRAN (Système d'Analyse Fournissant des Renseignements Adaptés à la Nivologie) high spatial resolution atmospheric reanalysis, the leaf area index (LAI) time courses derived from the ECOCLIMAP-II land surface parameter database and the soil texture derived from the French soil database. For climate, we focus on the radiations and rainfall variables and we test additional data sets which include the ERA-Interim (ERA-I) low spatial resolution reanalysis, the Global Precipitation Climatology Centre data set (GPCC) and the MeteoSat Second Generation (MSG) satellite estimate of downwelling shortwave radiations. The evaluation of the drivers indicates very low bias in daily downwelling shortwave radiation for ERA-I (2.5 W m-2) compared to the negative biases found for SAFRAN (-10 W m-2) and the MSG satellite (-12 W m-2). Both SAFRAN and ERA-I underestimate downwelling longwave radiations by -12 and -16 W m-2, respectively. The SAFRAN and ERA-I/GPCC rainfall are slightly biased at daily and longer timescales (1 and 0.5 % of the mean rainfall measurement). The SAFRAN rainfall is more precise than the ERA-I/GPCC estimate which shows larger inter-annual variability in yearly rainfall error (up to 100 mm). The ECOCLIMAP-II LAI climatology does not properly resolve Mediterranean crop phenology and underestimates the bare soil period which leads to an overall overestimation of LAI over the crop succession. The

  14. Impacts of Stream Flow and Climate Variability on Native and Invasive Woody Species in a Riparian Ecosystem of a Semi-Arid Region of the Great Plains, USA

    Science.gov (United States)

    Skolaut, K.; Awada, T.; Cherubini, P.; Schapaugh, A.

    2012-12-01

    Riparian ecosystems support diverse plant communities that exert direct and indirect biological, physical and chemical influence on, and are influenced by, adjacent water through both above and below-ground interactions. Historically, riparian areas of the northern Great Plains, US have been dominated by the native Populus deltoides (eastern cottonwood). This species relies on regular floods for regeneration and groundwater access for success. Over the past sixty years, changes in flow management and agricultural practices, coupled with climate variability and drought have altered stream flow and caused a dramatic decline in stream water yields and levels of groundwater. These and other biotic and biotic factors have promoted the expansion of the upland native woody species Juniperus virginiana (eastern redcedar), and the invasion of the non-native (introduced) Elaeagnus angustifolia (Russian olive) into riparian ecosystems. This invasion has further altered the water balance in the system and exasperated the problem of water scarcity with negative feedback on ecosystem services and growth of native woody species. The ability of P. deltoides to re-establish and grow is of concern for natural resource managers. Tree ring analysis of annual growth rates were used to determine 1) the responses P. deltoides and invasive J. virginiana and E. angustifulia to climate variability and stream flow regulation, and 2) the impacts of the two invasive species on the growth of native P. deltoides. Results show a dependency of growth for P. deltoides on the previous year summer temperature, and a less significant correlation to annual stream flow. J. virginiana showed the highest correlation to annual stream flow, as well as some dependency on the previous growing season precipitation. While the growth of both P. deltoides and J. virginiana displayed greater dependence on climatic factors, E. angustifolia displayed the lowest mean basal area growth and deviation from the growth. E

  15. Data Requirements for Developing Adaptations to Climate Variability and Change

    International Nuclear Information System (INIS)

    An extensive foundation of high quality data and information on the climate and on the biological, environmental and social systems affected by climate is required in order to understand the climate impact processes involved, to develop new adaptation practices, and to subsequently implement these practices. Experience of the impacts of current and past variability of climate and sea level is a prime source of information. Many practices are in use to reduce climate impacts, for example in engineering design, agricultural risk management and climate prediction services, though their roles as adaptations to climate change are not widely appreciated. While there are good data sets on some factors and in some regions, in many cases the databases are inadequate and there are few data sets on adaptation-specific quantities such as vulnerability, resilience and adaptation effectiveness. Current international action under the United Nations Framework Convention on Climate Change (UNFCCC) pays little attention to adaptation and its information requirements. Furthermore there are trends toward reduced data gathering and to restrictions on access to data sets, especially arising from cost and commercialisation pressures. To effectively respond to the changes in climate that are now inevitable, governments will need to more clearly identify adaptation as a central feature of climate change policy and make a renewed shared commitment to collecting and freely exchanging the necessary data. 12 refs

  16. Selection of climate change scenario data for impact modelling

    DEFF Research Database (Denmark)

    Sloth Madsen, M; Fox Maule, C; MacKellar, N;

    2012-01-01

    illustrates how the projected climate change signal of important variables as temperature, precipitation and relative humidity depends on the choice of the climate model. Using climate change projections from at least two different climate models is recommended to account for model uncertainty. To make...... the climate projections suitable for impact analysis at the local scale a weather generator approach was adopted. As the weather generator did not treat all the necessary variables, an ad-hoc statistical method was developed to synthesise realistic values of missing variables. The method is presented...... in this paper, applied to relative humidity, but it could be adopted to other variables if needed....

  17. Climate-mediated spatiotemporal variability in terrestrial productivity across Europe

    OpenAIRE

    Wu, X; F. Babst; Ciais, P.,; Frank, D.; Reichstein, M.; Wattenbach, M.; C. Zang; Mahecha, M. D.

    2014-01-01

    Quantifying the interannual variability (IAV) of the terrestrial ecosystem productivity and its sensitivity to climate is crucial for improving carbon budget predictions. In this context it is necessary to disentangle the influence of climate from impacts of other mechanisms underlying the spatiotemporal patterns of IAV of the ecosystem productivity. In this study we investigated the spatiotemporal patterns of IAV of historical observations of European crop yields in tandem ...

  18. Schneider lecture: From climate change impacts to climate change risks

    Science.gov (United States)

    Field, C. B.

    2014-12-01

    Steve Schneider was a strong proponent of considering the entire range of possible climate-change outcomes. He wrote and spoke frequently about the importance of low probability/high consequence outcomes as well as most likely outcomes. He worked tirelessly on communicating the risks from overlapping stressors. Technical and conceptual issues have made it difficult for Steve's vision to reach maturity in mainstream climate-change research, but the picture is changing rapidly. The concept of climate-change risk, considering both probability and consequence, is central to the recently completed IPCC Fifth Assessment Report, and the concept frames much of the discussion about future research agendas. Framing climate change as a challenge in managing risks is important for five core reasons. First, conceptualizing the issue as being about probabilities builds a bridge between current climate variability and future climate change. Second, a formulation based on risks highlights the fact that climate impacts occur primarily in extremes. For historical variability and future impacts, the real concern is the conditions under which things break and systems fail, namely, in the extremes. Third, framing the challenge as one of managing risks puts a strong emphasis on exploring the full range of possible outcomes, including low-probability, high/consequence outcomes. Fourth, explaining climate change as a problem in managing risks links climate change to a wide range of sophisticated risk management tools and strategies that underpin much of modern society. Fifth, the concept of climate change as a challenge in managing risks helps cement the understanding that climate change is a threat multiplier, adding new dimensions and complexity to existing and emerging problems. Framing climate change as a challenge in managing risks creates an important but difficult agenda for research. The emphasis needs to shift from most likely outcomes to most risky outcomes, considering the full

  19. Climatic Variability In Tropical Countries

    Science.gov (United States)

    Seneviratne, L. W.

    2003-04-01

    Introduction Droughts in tropical countries are proved as periodic and its occurrence is shown remarkable in 9.25 year cycles as explained by the author. These cycles exist as soon or late around the central point. In the tropical regions monsoons or trade winds has a definite origin and pattern of advancing towards land mass. Ocean evaporation is the main source of rain clouds, which is drifted on to low vapour pressure zones. In the drought situation low vapour pressure zones are reduced and high vapour pressure zones are increased. Evaporation is reduced and incident solar radiation (insolation) is relatively reduced. Wind effect needed to form a cloud is low. Dry wind is passing along the land mass. Most rainy lands are subjected to prolonged droughts and hence cultivation is affected. Drought impacts create severe losses to irrigation projects. Civilization is affected by lack of food production. Lack of drinking water entirely eliminates the living animals and creatures. Eco system slowly changes to dried jungles and abandoned skeletons. Tropical conditions Sri Lanka experienced drought in 2001. Hambanthota District suffered for entire year 2000 with low rainfall. This area is not in line with monsoons and mountain ranges are not available to form dynamic cooling of air. So as the Puttalam and Mannar Districts Rainfall is very low in these areas. Drought continued for 2001 and half of 2002 in the main land. Hambanthota District is still continuing with low rainfall. The central mountains are well placed to bring monsoon rains. This position is not purely effective to form sufficient precipitation in drought years. The reason is highly stable atmosphere in this region. Due to global warming of 1deg C in 60 years and high carbon dioxide gas creating high density in low atmospheres, evaporation and rainmaking has a general reduction. It is identified by the author that the common plane episode of Moon and Earth, which occurs in 9.25 years is creating stable

  20. The Social Impact of Climate

    Science.gov (United States)

    Hsiang, S. M.

    2013-12-01

    Managing climate change requires that we understand the social value of climate-related decisions. Rational decision-making demands that we weigh the potential benefits of climate-related investments against their costs. To date, it has been challenging to quantify the relative social benefit of living under different climatic conditions, so policy debates tend to focus on investment costs without considering their benefits. Here I will discuss challenges and advances in the measurement of climate's impact on society. By linking data and methods across physical and social sciences, we are beginning to understand when, where, and how climatic conditions have a causal impact on human wellbeing. I will present examples from this burgeoning interdisciplinary field that quantify the effect of temperature on macroeconomic performance, the effects of climate on human conflict, and the long-term health and economic impact of tropical cyclones. Each of these examples provide new insight into previously unknown benefits of various climate management strategies. I conclude by describing new efforts to systematically gather and compare findings from across the research community to support informed and rational climate management decisions.

  1. Climatic variability and human impact during the last 2000 years in western Mesoamerica: evidence of late Classic (AD 600-900) and Little Ice Age drought events

    Science.gov (United States)

    Rodríguez-Ramírez, A.; Caballero, M.; Roy, P.; Ortega, B.; Vázquez-Castro, G.; Lozano-García, S.

    2015-09-01

    We present results of analysis of biological (diatoms and ostracodes) and non-biological (Ti, Ca / Ti, total inorganic carbon, magnetic susceptibility) variables from an 8.8 m long, high-resolution (~ 20 yr sample-1) laminated sediment sequence from Lake Santa María del Oro (SMO), western Mexico. This lake lies at a sensitive location between the dry climates of northern Mexico, under the influence of the North Pacific subtropical high-pressure cell and the moister climates of central Mexico, under the influence of the seasonal migration of the intertropical convergence zone and the North American monsoon (NAM). The sequence covers the last 2000 years and provides evidence of two periods of human impact in the catchment, shown by increases in the diatom Achnanthidium minutissimum. The first from AD 100 to 400 (Early Classic) is related to the shaft and chamber tombs cultural tradition in western Mexico, and the second is related to Post-Classic occupation from AD 1100 to 1300. Both periods correspond to relatively wet conditions. Three dry intervals are identified from increased carbonate and the presence of ostracodes and aerophilous Eolimna minima. The first, from AD 500 to 1000 (most intense during the late Classic, from AD 600 to 800), correlates with the end of the shaft and chamber tradition in western Mexico after ca. AD 600. This late Classic dry period is the most important climatic signal in the Mesoamerican region during the last 2000 years, and has been recorded at several sites from Yucatan to the Pacific coast. In the Yucatan area, this dry interval has been related with the demise of the Maya culture at the end of the Classic (AD 850 to 950). The last two dry events (AD 1400 to 1550 and 1690 to 1770) correspond with the onset of, and the late, Little Ice Age, and follow largely the Spörer and Maunder minima in solar radiation. The first of these intervals (AD 1400 to 1550) shows the most intense signal over western Mexico; however this pattern is

  2. Human Responses to Climate Variability: The Case of South Africa

    Science.gov (United States)

    Oppenheimer, M.; Licker, R.; Mastrorillo, M.; Bohra-Mishra, P.; Estes, L. D.; Cai, R.

    2014-12-01

    Climate variability has been associated with a range of societal and individual outcomes including migration, violent conflict, changes in labor productivity, and health impacts. Some of these may be direct responses to changes in mean temperature or precipitation or extreme events, such as displacement of human populations by tropical cyclones. Others may be mediated by a variety of biological, social, or ecological factors such as migration in response to long-term changes in crops yields. Research is beginning to elucidate and distinguish the many channels through which climate variability may influence human behavior (ranging from the individual to the collective, societal level) in order to better understand how to improve resilience in the face of current variability as well as future climate change. Using a variety of data sets from South Africa, we show how climate variability has influenced internal (within country) migration in recent history. We focus on South Africa as it is a country with high levels of internal migration and dramatic temperature and precipitation changes projected for the 21st century. High poverty rates and significant levels of rain-fed, smallholder agriculture leave large portions of South Africa's population base vulnerable to future climate change. In this study, we utilize two complementary statistical models - one micro-level model, driven by individual and household level survey data, and one macro-level model, driven by national census statistics. In both models, we consider the effect of climate on migration both directly (with gridded climate reanalysis data) and indirectly (with agricultural production statistics). With our historical analyses of climate variability, we gain insights into how the migration decisions of South Africans may be influenced by future climate change. We also offer perspective on the utility of micro and macro level approaches in the study of climate change and human migration.

  3. 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

  4. Randomness and Earth climate variability

    CERN Document Server

    Levinshtein, Michael E; Dmitriev, Alexander P; Shmakov, Pavel M

    2015-01-01

    Paleo-Sciences including palaeoclimatology and palaeoecology have accumulated numerous records related to climatic changes. The researchers have usually tried to identify periodic and quasi-periodic processes in these paleoscientific records. In this paper, we show that this analysis is incomplete. As follows from our results, random processes, namely processes with a single-time-constant (noise with a Lorentzian noise spectrum), play a very important and, perhaps, a decisive role in numerous natural phenomena. For several of very important natural phenomena the characteristic time constants are very similar and equal to (5-8)x10^3 years. However, this value is not universal. For example, the spectral density fluctuations of the atmospheric radiocarbon 14C are characterized by a Lorentzian with time constant 300 years. The frequency dependence of spectral density fluctuations for benthic 18O records contains two Lorentzians with time constans 8000 years and > 105 years.

  5. Vulnerability of sandy coasts to climate variability

    OpenAIRE

    Idier, Deborah; Castelle, Bruno; Poumadère, Marc.; Balouin, Yann; Bohn Bertoldo, Raquel; Bouchette, Fréderic; Boulahya, Faiza; Brivois, Olivier; Calvete Manrique, Daniel; Capo, Sylvain; Certain, Raphael; Charles, Elodie; Chateauminois, Eric; Delvallée, Etienne; Falqués Serra, Albert

    2013-01-01

    The main objective of the VULSACO (VULnerability of SAndy COasts to climate change and anthropic pressure) project was to investigate present day and potential future vulnerability of sandy coasts at the 2030 horizon, i.e. on a time scale related to climate variability. The method, based on a multidisciplinary approach bringing together geologists, geographers, physicists, social psychologists, engineers and stakeholders, was structured around 4 axes: field data analysis; numerical modelling;...

  6. Human activity and climate variability project: annual report 2001

    International Nuclear Information System (INIS)

    Knowledge of the state of the Australian environment, including natural climate variability, prior to colonial settlement is vital if we are to define and understand the impact of over two hundred years of post-industrial human activity on our landscape. ANSTO, in conjunction with university partners, is leading a major research effort to provide natural archives of human activity and climate variability over the last 500 years in Australia, utilising a variety of techniques, including lead-210 and radiocarbon dating and analyses of proxy indicators (such as microfossils) as well as direct evidence (such as trace elements) of human activity and climate variability. The other major project objectives were to contribute to the understanding of the impact of human induced and natural aerosols in the East Asian region on climate through analysis and sourcing of fine particles and characterisation of air samples using radon concentrations and to contribute to the improvement of land surface parameterisation schemes and investigate the potential to use stable isotopes to improve global climate models and thus improve our understanding of future climate

  7. Farmers' Perceptions of Climate Variability and Factors Influencing Adaptation: Evidence from Anhui and Jiangsu, China

    Science.gov (United States)

    Kibue, Grace Wanjiru; Liu, Xiaoyu; Zheng, Jufeng; zhang, Xuhui; Pan, Genxing; Li, Lianqing; Han, Xiaojun

    2016-05-01

    Impacts of climate variability and climate change are on the rise in China posing great threat to agriculture and rural livelihoods. Consequently, China is undertaking research to find solutions of confronting climate change and variability. However, most studies of climate change and variability in China largely fail to address farmers' perceptions of climate variability and adaptation. Yet, without an understanding of farmers' perceptions, strategies are unlikely to be effective. We conducted questionnaire surveys of farmers in two farming regions, Yifeng, Jiangsu and Qinxi, Anhui achieving 280 and 293 responses, respectively. Additionally, we used climatological data to corroborate the farmers' perceptions of climate variability. We found that farmers' were aware of climate variability such that were consistent with climate records. However, perceived impacts of climate variability differed between the two regions and were influenced by farmers' characteristics. In addition, the vast majorities of farmers were yet to make adjustments in their farming practices as a result of numerous challenges. These challenges included socioeconomic and socio-cultural barriers. Results of logit modeling showed that farmers are more likely to adapt to climate variability if contact with extension services, frequency of seeking information, household heads' education, and climate variability perceptions are improved. These results suggest the need for policy makers to understand farmers' perceptions of climate variability and change in order to formulate policies that foster adaptation, and ultimately protect China's agricultural assets.

  8. Climate variability and climate change vulnerability and adaptation. Workshop summary

    International Nuclear Information System (INIS)

    Representatives from fifteen countries met in Prague, Czech Republic, on September 11-15, 1995, to share results from the analysis of vulnerability and adaptation to global climate change. The workshop focused on the issues of global climate change and its impacts on various sectors of a national economy. The U.N. Framework Convention on Climate Change (FCCC), which has been signed by more than 150 governments worldwide, calls on signatory parties to develop and communicate measures they are implementing to respond to global climate change. An analysis of a country's vulnerability to changes in the climate helps it identify suitable adaptation measures. These analyses are designed to determine the extent of the impacts of global climate change on sensitive sectors such as agricultural crops, forests, grasslands and livestock, water resources, and coastal areas. Once it is determined how vulnerable a country may be to climate change, it is possible to identify adaptation measures for ameliorating some or all of the effects.The objectives of the vulnerability and adaptation workshop were to: The objectives of the vulnerability and adaptation workshop were to: Provide an opportunity for countries to describe their study results; Encourage countries to learn from the experience of the more complete assessments and adjust their studies accordingly; Identify issues and analyses that require further investigation; and Summarize results and experiences for governmental and intergovernmental organizations

  9. Permafrozen temperature regime affected by climate variability

    International Nuclear Information System (INIS)

    The paper reports on the numerical-analytical solution for the problem of periodically constant heat exchange in permafrost. There are no initial conditions and the task at issue is based upon the soil conductive heat exchange simulation. In addition, at thawing or freezing, the parameters of water/ice transition, geothermal temperature gradient and the snow cover impact upon the soil heat transition to outer ground have also been taken into account. This solution is governed by the following characteristics: annual air temperature change; winter precipitation accumulation; thermo-physical soil properties either in thawed or in frozen state. Considering the adduced solution the following parameters can be determined: the soil temperature at zero year amplitude level; the frost penetration lower boundary depth; and others. The calculated data are presented and compared with the results of previous field tests. The influence of the quantitative characteristics, such as variable climate and winter precipitation accumulation, upon the soil temperature pattern will be shown; in particular, the frost penetration lower boundary depth is varied by yearly average temperature increase or decrease. The regions where one-two degree yearly average temperature increases result in total permafrost disappearance have been located

  10. Potential future impacts of climatic change on the Great Plains

    International Nuclear Information System (INIS)

    A synopsis is provided of approaches to impact studies in the Great Plains, findings from studies of future impacts are summarized, and opportunities for enhancing understanding of future impacts are discussed. Potential impacts of climate change on agriculture, water resources, forestry, recreation/tourism, and energy are summarized. Impact analyses need to look more rigorously at variability in climate, the probabilities of various climatic conditions, and the sensitivity of social and economic activities to climatic variability. Most economic impact studies have assumed no adaptive behavior on the part of economic decision makers. Credible impact assessments require an improved understanding of the sensitivity and adaptability of sectors to climatic conditions, particularly variability. The energy sector in the Great Plains region is likely to be more sensitive to political developments in the Middle East than to climatic variability and change. Speculation and analysis of climate impacts have focused on supply conditions and demands, yet the sector is more keenly sensitive to policy implications of climatic change, such as the potential for fossil fuel taxes or other legislative or pricing constraints. 28 refs

  11. Expected impacts of climate change on extreme climate events

    International Nuclear Information System (INIS)

    An overview of the expected change of climate extremes during this century due to greenhouse gases and aerosol anthropogenic emissions is presented. The most commonly used methodologies rely on the dynamical or statistical down-scaling of climate projections, performed with coupled atmosphere-ocean general circulation models. Either of dynamical or of statistical type, down-scaling methods present strengths and weaknesses, but neither their validation on present climate conditions, nor their potential ability to project the impact of climate change on extreme event statistics allows one to give a specific advantage to one of the two types. The results synthesized in the last IPCC report and more recent studies underline a convergence for a very likely increase in heat wave episodes over land surfaces, linked to the mean warming and the increase in temperature variability. In addition, the number of days of frost should decrease and the growing season length should increase. The projected increase in heavy precipitation events appears also as very likely over most areas and also seems linked to a change in the shape of the precipitation intensity distribution. The global trends for drought duration are less consistent between models and down-scaling methodologies, due to their regional variability. The change of wind-related extremes is also regionally dependent, and associated to a poleward displacement of the mid-latitude storm tracks. The specific study of extreme events over France reveals the high sensitivity of some statistics of climate extremes at the decadal time scale as a consequence of regional climate internal variability. (authors)

  12. An Agenda for Climate Impacts Science

    Science.gov (United States)

    Kaye, J. A.

    2009-12-01

    The report Global Change Impacts in the United States released by the US Global Change Research Program in June 2009 identifies a number of areas in which inadequate information or understanding hampers our ability to estimate likely future climate change and its impacts. In this section of the report, the focus is on those areas of climate science that could contribute most towards advancing our knowledge of climate change impacts and those aspects of climate change responsible for these impacts in order to continue to guide decision making. The Report identifies the six most important gaps in knowledge and offers some thoughts on how to address those gaps: 1. Expand our understanding of climate change impacts. There is a clear need to increase understanding of how ecosystems, social and economic systems, human health, and the built environment will be affected by climate change in the context of other stresses. 2. Refine ability to project climate change, including extreme events, at local scales. While climate change is a global issue, it has a great deal of regional variability. There is an indisputable need to improve understanding of climate system effects at these smaller scales, because these are often the scales of decision-making in society. This includes advances in modeling capability and observations needed to address local scales and high-impact extreme events. 3. Expand capacity to provide decision makers and the public with relevant information on climate change and its impacts. Significant potential exists in the US to create more comprehensive measurement, archive, and data-access systems that could provide great benefit to society, which requires defining needed information, gathering it, expanding capacity to deliver it, and improving tools by which decision makers use it to best advantage. 4. Improve understanding of thresholds likely to lead to abrupt changes in climate or ecosystems. Potential areas of research include thresholds that could

  13. Climate Change Impacts and Risks for Animal Health in Asia

    OpenAIRE

    Forman, S.; Hungerford, N.; Yamakawa, M; Yanase, T.; Tsai, H J; Joo, Y.S.; Yang, D. K.; Nha, J. J.

    2008-01-01

    The threat of climate change and global warming is now recognised worldwide and some alarming manifestations of change have occurred. The Asian continent, because of its size and diversity, may be affected significantly by the consequences of climate change, and its new status as a 'hub' of livestock production gives it an important role in mitigating possible impacts of climate variability on animal health. Animal health may be affected by climate change in four ways: heat-related diseases a...

  14. Quantifying the sources of uncertainty in upper air climate variables

    Science.gov (United States)

    Eghdamirad, Sajjad; Johnson, Fiona; Woldemeskel, Fitsum; Sharma, Ashish

    2016-04-01

    Future estimates of precipitation and streamflow are of utmost interest in hydrological climate change impact assessments. Just as important as the estimate itself, is the variance around the ensemble mean of the projections, this variance being defined as uncertainty in the context of this study. This uncertainty in the hydrological variables of interest is affected by uncertainty in upper air climate variables which are used in statistical downscaling of precipitation or streamflow. Here the extent of uncertainty in upper air climate variables has been assessed for a selection of commonly used atmospheric variables for downscaling, namely, geopotential height and its difference in the north-south direction, specific humidity, and eastward and northward wind speeds. Generally, in statistical downscaling, no consideration is usually given to the uncertainty of different individual variables, which can result in biases in future climate simulations. The approach of quantifying uncertainty presented here has the potential to enable modelers to better formulate downscaling approaches, leading to more accurate characterization of future precipitation and its associated uncertainty. Based on the spread of multiple-model outputs, an uncertainty measure called square root of error variance has been used to quantify the contribution of different sources of uncertainty (i.e., models, scenarios, and ensembles) in monthly future climate projections in the 21st century at the 500 hPa and 850 hPa pressure levels. It has been shown that the different climate variables and levels of the atmosphere have distinct patterns in terms of their total future uncertainty and the contributions from the three sources. Scenario and model uncertainties in general contribute reasonably evenly to total uncertainty, with smaller contributions from the initial condition ensembles.

  15. Impact of change in climate and policy from 1988 to 2007 on environmental and microbial variables at the time series station Boknis Eck, Baltic Sea

    Directory of Open Access Journals (Sweden)

    H.-G. Hoppe

    2012-12-01

    Full Text Available Phytoplankton and bacteria are sensitive indicators of environmental change. The temporal development of these key organisms was monitored from 1988 to the end of 2007 at the time series station Boknis Eck in the Western Baltic Sea. This period was characterized by the adaption of the Baltic Sea ecosystem to changes in the environmental conditions caused by the collapse and conversion of the political system in the Southern and Eastern Border States, accompanied by the general effects of global climate change. Measured variables were chlorophyll, primary production, bacteria number, -biomass and -production, glucose turnover rate, macro-nutrients, pH, temperature and salinity. Negative trends with time were recorded for chlorophyll, the bacterial variables, nitrate, ammonia, phosphate, silicate, oxygen and salinity while temperature, pH, and the ratio between bacteria numbers and chlorophyll increased. The strongest reductions with time occurred for the annual maximum values, e.g. for chlorophyll during the spring bloom or for nitrate during winter, while the annual minimum values remained more stable. In deep water above sediment the negative trends of oxygen, nitrate, phosphate and bacterial variables as well as the positive trend of temperature were similar to those in the surface while the trends of salinity, ammonia and silicate were opposite to those in the surface. Decreasing oxygen even in the surface layer was of particular interest because it suggested enhanced recycling of nutrients from the deep hypoxic zones to the surface by vertical mixing. In the long run all variables correlated positively with temperature, except chlorophyll and salinity. Salinity correlated negatively with all bacterial variables as well as precipitation and positively with chlorophyll. Surprisingly, bacterial variables did not correlate with chlorophyll which may be inherent with the time lag between the peaks of phytoplankton and bacteria during spring

  16. 2500 Years of European Climate Variability and Human Susceptibility

    Science.gov (United States)

    Büntgen, Ulf; Tegel, Willy; Nicolussi, Kurt; McCormick, Michael; Frank, David; Trouet, Valerie; Kaplan, Jed O.; Herzig, Franz; Heussner, Karl-Uwe; Wanner, Heinz; Luterbacher, Jürg; Esper, Jan

    2011-02-01

    Climate variations influenced the agricultural productivity, health risk, and conflict level of preindustrial societies. Discrimination between environmental and anthropogenic impacts on past civilizations, however, remains difficult because of the paucity of high-resolution paleoclimatic evidence. We present tree ring-based reconstructions of central European summer precipitation and temperature variability over the past 2500 years. Recent warming is unprecedented, but modern hydroclimatic variations may have at times been exceeded in magnitude and duration. Wet and warm summers occurred during periods of Roman and medieval prosperity. Increased climate variability from ~250 to 600 C.E. coincided with the demise of the western Roman Empire and the turmoil of the Migration Period. Such historical data may provide a basis for counteracting the recent political and fiscal reluctance to mitigate projected climate change.

  17. Climate change impacts and adaptations

    DEFF Research Database (Denmark)

    Arndt, Channing; Tarp, Finn

    2015-01-01

    inseparability of the development and climate agendas, and the rate of assimilation of climate and development information in key institutions. They are drawn from the Development Under Climate Change (DUCC) project carried out by UNU-WIDER of which the countries of the Greater Zambeze Valley formed a part......In this article, we assert that developing countries are much better prepared to undertake negotiations at the Conference of the Parties in Paris (CoP21) as compared to CoP15 in Copenhagen. An important element of this is the accumulation of knowledge with respect to the implications of climate...... change and the ongoing internalization thereof by key institutions in developing countries. The articles in this special issue set forth a set of technical contributions to this improved understanding. We also summarize five major lessons related to uncertainty, extreme events, timing of impacts, the...

  18. Impact of Climate Change on Riverbank Erosion

    Directory of Open Access Journals (Sweden)

    Most. Nazneen Aktar

    2014-04-01

    Full Text Available Bangladesh is one of the most climate vulnerable countries in the world. This country is highly vulnerable to climate change because of a number of hydro-geological and socio-economic factors such as geographical location, topography, extreme climate variability, high population density, poverty incidence and dependency of agriculture on climate. Presently this country has been experiencing different hydro-meteorological disastrous events that have never been experienced before. Along with other natural disasters, floods are expected to be impacted by climate change in the future. Since floods are always associated with riverbank erosion, it is essential to assess the impact of climate change on bank erosion. Riverbank erosion is also a serious hazard that directly or indirectly causes the suffering of millions of people. Beyond that, most of the old cities and important infrastructures in this country are situated on riverbanks since once upon a time waterway transportation was the main mode of travel. Moreover, people like to reside near rivers because of their dependency on river water for irrigation purposes. So a major part of the total population of this country lives near riverbanks, which frequently makes them victims of riverbank erosion. The major rivers, the Jamuna, the Ganges and the Padma, annually erode thousand hectares of floodplain land and damage or destroy infrastructures. Consequently, this natural disaster has become a major social hazard. This study aims to find out the relationship between floods and bank erosion; and hence the impact of climate changes on riverbank erosion. Since there is no record on riverbank erosion, this study attempts to measure it with the help of satellite images. It has been found in this study that climate change will play a significant role in riverbank erosion. On an average, the riverbank erosion along the major three rivers will be increased by 13% by 2050 and it will be increased by 18% by

  19. Impact of change in climate and policy from 1988 to 2007 on environmental and microbial variables at the time series station Boknis Eck, Baltic Sea

    Directory of Open Access Journals (Sweden)

    H.-G. Hoppe

    2013-07-01

    Full Text Available Phytoplankton and bacteria are sensitive indicators of environmental change. The temporal development of these key organisms was monitored from 1988 to the end of 2007 at the time series station Boknis Eck in the western Baltic Sea. This period was characterized by the adaption of the Baltic Sea ecosystem to changes in the environmental conditions caused by the conversion of the political system in the southern and eastern border states, accompanied by the general effects of global climate change. Measured variables were chlorophyll, primary production, bacteria number, -biomass and -production, glucose turnover rate, macro-nutrients, pH, temperature and salinity. Negative trends with time were recorded for chlorophyll, bacteria number, bacterial biomass and bacterial production, nitrate, ammonia, phosphate, silicate, oxygen and salinity while temperature, pH, and the ratio between bacteria numbers and chlorophyll increased. Strongest reductions with time occurred for the annual maximum values, e.g. for chlorophyll during the spring bloom or for nitrate during winter, while the annual minimum values remained more stable. In deep water above sediment the negative trends of oxygen, nitrate, phosphate and bacterial variables as well as the positive trend of temperature were similar to those in the surface while the trends of salinity, ammonia and silicate were opposite to those in the surface. Decreasing oxygen, even in the surface layer, was of particular interest because it suggested enhanced recycling of nutrients from the deep hypoxic zones to the surface by vertical mixing. The long-term seasonal patterns of all variables correlated positively with temperature, except chlorophyll and salinity. Salinity correlated negatively with all bacterial variables (as well as precipitation and positively with chlorophyll. Surprisingly, bacterial variables did not correlate with chlorophyll, which may be inherent with the time lag between the peaks of

  20. Space-time structure of climate variability

    Science.gov (United States)

    Laepple, Thomas; Reschke, Maria; Huybers, Peter; Rehfeld, Kira

    2016-04-01

    The spatial scale of climate variability is closely linked to the temporal scale. Whereas fast variations such as weather are regional, glacial-interglacial cycles appear to be globally coherent. Quantifying the relationship between local and large-scale climate variations is essential for mapping the extent of past climate changes. Larger spatial scales of climate variations on longer time scales are expected if one views the atmosphere and oceans as primarily diffusive with respect to heat. On the other hand, the interaction of a dynamical system with spatially variable boundary conditions --- for example: topography, gradients in insolation, and variations in rotational effects --- will lead to spatially heterogeneous structures that are largely independent of time scale. It has been argued that the increase in spatial scales continues across all time scales [Mitchell, 1976], but up to now, the space-time structure of variations beyond the decadal scale is basically unexplored. Here, we attempt to estimate the spatial extent of temperature changes up to millennial time-scales using instrumental observations, paleo-observations and climate model simulations. Although instrumental and climate model data show an increase in spatial scale towards slower variations, paleo-proxy data, if interpreted as temperature signals, lead to ambiguous results. An analysis of a global Holocene stack [Marcott et al., 2013], for example, suggests a jump towards more localized patterns when leaving the instrumental time scale. Localization contradicts physical expectations and may instead reflect the presence of various types of noise. Turning the problem around, and imposing a consistent space-time structure across instruments and proxy records allows us to constrain the interpretation of the climate signal in proxy records. In the case of the Holocene stack, preliminary results suggest that the time-uncertainty on the Holocene records would have to be much larger than published in

  1. Tufted puffin reproduction reveals ocean climate variability

    OpenAIRE

    Gjerdrum, Carina; Vallée, Anne M. J.; St. Clair, Colleen Cassady; Bertram, Douglas F.; John L. Ryder; Blackburn, Gwylim S.

    2003-01-01

    Anomalously warm sea-surface temperatures (SSTs) are associated with interannual and decadal variability as well as with long-term climate changes indicative of global warming. Such oscillations could precipitate changes in a variety of oceanic processes to affect marine species worldwide. As global temperatures continue to rise, it will be critically important to be able to predict the effects of such changes on species' abundance, distribution, and ecological relatio...

  2. Smallholder agriculture in India and adaptation to current and future climate variability and climate change

    Science.gov (United States)

    Murari, K. K.; Jayaraman, T.

    2014-12-01

    Modeling studies have indicated that global warming, in many regions, will increase the exposure of major crops to rainfall and temperature stress, leading to lower crop yields. Climate variability alone has a potential to decrease yield to an extent comparable to or greater than yield reductions expected due to rising temperature. For India, where agriculture is important, both in terms of food security as well as a source of livelihoods to a majority of its population, climate variability and climate change are subjects of serious concern. There is however a need to distinguish the impact of current climate variability and climate change on Indian agriculture, especially in relation to their socioeconomic impact. This differentiation is difficult to determine due to the secular trend of increasing production and yield of the past several decades. The current research in this aspect is in an initial stage and requires a multi-disciplinary effort. In this study, we assess the potential differential impacts of environmental stress and shock across different socioeconomic strata of the rural population, using village level survey data. The survey data from eight selected villages, based on the Project on Agrarian Relations in India conducted by the Foundation for Agrarian Studies, indicated that income from crop production of the top 20 households (based on the extent of operational land holding, employment of hired labour and asset holdings) is a multiple of the mean income of the village. In sharp contrast, the income of the bottom 20 households is a fraction of the mean and sometimes negative, indicating a net loss from crop production. The considerable differentials in output and incomes suggest that small and marginal farmers are far more susceptible to climate variability and climate change than the other sections. Climate change is effectively an immediate threat to small and marginal farmers, which is driven essentially by socioeconomic conditions. The impact

  3. Sensitivity of global terrestrial ecosystems to climate variability.

    Science.gov (United States)

    Seddon, Alistair W R; Macias-Fauria, Marc; Long, Peter R; Benz, David; Willis, Kathy J

    2016-03-10

    The identification of properties that contribute to the persistence and resilience of ecosystems despite climate change constitutes a research priority of global relevance. Here we present a novel, empirical approach to assess the relative sensitivity of ecosystems to climate variability, one property of resilience that builds on theoretical modelling work recognizing that systems closer to critical thresholds respond more sensitively to external perturbations. We develop a new metric, the vegetation sensitivity index, that identifies areas sensitive to climate variability over the past 14 years. The metric uses time series data derived from the moderate-resolution imaging spectroradiometer (MODIS) enhanced vegetation index, and three climatic variables that drive vegetation productivity (air temperature, water availability and cloud cover). Underlying the analysis is an autoregressive modelling approach used to identify climate drivers of vegetation productivity on monthly timescales, in addition to regions with memory effects and reduced response rates to external forcing. We find ecologically sensitive regions with amplified responses to climate variability in the Arctic tundra, parts of the boreal forest belt, the tropical rainforest, alpine regions worldwide, steppe and prairie regions of central Asia and North and South America, the Caatinga deciduous forest in eastern South America, and eastern areas of Australia. Our study provides a quantitative methodology for assessing the relative response rate of ecosystems--be they natural or with a strong anthropogenic signature--to environmental variability, which is the first step towards addressing why some regions appear to be more sensitive than others, and what impact this has on the resilience of ecosystem service provision and human well-being. PMID:26886790

  4. Sensitivity of global terrestrial ecosystems to climate variability

    Science.gov (United States)

    Seddon, Alistair W. R.; Macias-Fauria, Marc; Long, Peter R.; Benz, David; Willis, Kathy J.

    2016-03-01

    The identification of properties that contribute to the persistence and resilience of ecosystems despite climate change constitutes a research priority of global relevance. Here we present a novel, empirical approach to assess the relative sensitivity of ecosystems to climate variability, one property of resilience that builds on theoretical modelling work recognizing that systems closer to critical thresholds respond more sensitively to external perturbations. We develop a new metric, the vegetation sensitivity index, that identifies areas sensitive to climate variability over the past 14 years. The metric uses time series data derived from the moderate-resolution imaging spectroradiometer (MODIS) enhanced vegetation index, and three climatic variables that drive vegetation productivity (air temperature, water availability and cloud cover). Underlying the analysis is an autoregressive modelling approach used to identify climate drivers of vegetation productivity on monthly timescales, in addition to regions with memory effects and reduced response rates to external forcing. We find ecologically sensitive regions with amplified responses to climate variability in the Arctic tundra, parts of the boreal forest belt, the tropical rainforest, alpine regions worldwide, steppe and prairie regions of central Asia and North and South America, the Caatinga deciduous forest in eastern South America, and eastern areas of Australia. Our study provides a quantitative methodology for assessing the relative response rate of ecosystems—be they natural or with a strong anthropogenic signature—to environmental variability, which is the first step towards addressing why some regions appear to be more sensitive than others, and what impact this has on the resilience of ecosystem service provision and human well-being.

  5. ClimateImpactsOnline: A web platform for regional climate impacts

    Science.gov (United States)

    Nocke, Thomas

    2013-04-01

    Climate change is widely known but there is often uncertainty about the specific effects. One of the key tasks is - beyond discussing climate change and its impacts in specialist groups - to present these to a wider audience. In that respect, decision-makers in the public sector as well as directly affected professional groups require to obtain easy-to-understand information. These groups are not made up of specialist scientists. This gives rise to two challenges: (1) the complex information must be presented such that it is commonly understood, and (2) access to the information must be easy. Interested parties do not have time to familiarize themselves over a lengthy period, but rather want to immediately work with the information. Beside providing climate information globally, regional information become of increasing interest for local decision making regarding awareness building and adaptation options. In addition, current web portals mainly focus on climate information, considering climate impacts on different sectors only implicitly. As solution, Potsdam Institute for Climate Impact Research and WetterOnline have jointly developed an Internet portal that is easy to use, groups together interesting information about climate impacts and offers it in a directly usable form. This new web portal ClimateImpactsOnline.com provides detailed information, combining multiple sectors for the test case of Germany. For this region, numerous individual studies on climate change have been prepared by various institutions. These studies differ in terms of their aim, region and time period of interest. Thus, the goal of ClimateImpactsOnline.com is to present a synthesized view on regional impacts of global climate change on hydrology, agriculture, forest, energy, tourism and health sector. The climate and impact variables are available on a decadal time resolution for the period from 1901-2100, combining observed data and future projections. Detailed information are presented

  6. Solar Variability in the Context of Other Climate Forcing Mechanisms

    Science.gov (United States)

    Hansen, James E.

    1999-01-01

    I compare and contrast climate forcings due to solar variability with climate forcings due to other mechanisms of climate change, interpretation of the role of the sun in climate change depends upon climate sensitivity and upon the net forcing by other climate change mechanisms. Among the potential indirect climate forcings due to solar variability, only that due to solar cycle induced ozone changes has been well quantified. There is evidence that the sun has been a significant player in past climate change on decadal to century time scales, and that it has the potential to contribute to climate change in the 21st century.

  7. Effects of climate change and variability on population dynamics in a long-lived shorebird

    NARCIS (Netherlands)

    van de Pol, Martijn; Vindenes, Yngvild; Saether, Bernt-Erik; Engen, Steinar; Ens, Bruno J.; Oosterbeek, Kees; Tinbergen, Joost M.

    2010-01-01

    Climate change affects both the mean and variability of climatic variables, but their relative impact on the dynamics of populations is still largely unexplored. Based on a long-term study of the demography of a declining Eurasian Oystercatcher (Haematopus ostralegus) population, we quantify the eff

  8. Modelling climate control on cropland and grassland development using phenologically tuned variables

    DEFF Research Database (Denmark)

    Horion, Stéphanie Marie Anne F; Tychon, Bernard; Cornet, Yves

    2010-01-01

    Many studies already investigated the impact of climate change and climate variability on vegetation at global and continental scales. Using time series of remote sensing and climate data, Nemani et al. (2003) analyzed trends in Net Primary Production in relation with changes in climate and showed...... that, between 1982 and 1999, primary productivity increased by 6% globally in response to climate change. This study also stressed the need to take into account the spatial variability of climatic constraints to plant growth when analyzing the climate change impact on vegetation. Others authors...... described different phenomenon linked with climate change such as increases of seasonal NDVI amplitude and growing season duration in the Northern high latitude or changes in circumpolar photosynthetic activities. Understanding the interactions between climate and vegetation is also a key issue in our Ph...

  9. Simulation of climate variability and anthropogenic climate change

    International Nuclear Information System (INIS)

    The climatic changes in the last century were discussed and focus was on the questions: 1) What are the causes of the rapid climate fluctuations and 2) Is the global warming, which is observed during the last century, caused by natural or anthropogenic effects. It is concluded that an understanding of climate based on the interpretation of observational data only is not feasible, unless supported by an adequate theoretical interpretation. The capabilities of climatic models were discussed and the importance of incorporating 1) calculations of the internal variability of the atmosphere when forced from an ocean with prescribed sea surface temperature as well as for a system consisting of an atmosphere and a mixed ocean of limited depth, 2) a fully coupled atmospheric and ocean model and finally, 3) a fully coupled system including transiently changing greenhouse gases and aerosols. A short summation of the results is presented. The pronounced warming during the last century is not reproduced under the assumption of constant forcing and pollution emissions have to be incorporated into the models in order to bring the simulated data in agreement with observations

  10. Climate variability and Great Plains agriculture

    International Nuclear Information System (INIS)

    The ways in which inhabitants of the Great Plains, including Indians, early settlers, and 20th century farmers, have adapted to climate changes on the Great Plains are explored. The climate of the Great Plains, because of its variability and extremes, can be very stressful to plants, animals and people. It is suggested that agriculture and society on the Great Plains have, during the last century, become less vulnerable to the stresses imposed by climate. Opinions as to the sustainability of agriculture on the Great Plains vary substantially. Lockeretz (1981) suggests that large scale, high cost technologies have stressed farmers by creating surpluses and by requiring large investments. Opie (1989) sees irrigation as a climate substitute, however he stresses that the Ogallala aquifer must inevitably become depleted. Deborah and Frank Popper (1987) believe that farming on the Plains is unsustainable, and destruction of shelterbelts, out-migration of the rural population and environmental problems will lead to total collapse. With global warming, water in the Great Plains is expected to become scarcer, and although improvements in irrigation efficiency may slow depletion of the Ogallala aquifer, ultimately the acreage under irrigation must decrease to levels that can be sustained by natural recharge and reliable surface flows. 23 refs., 2 figs

  11. Climatic Impact of Volcanic Eruptions

    Directory of Open Access Journals (Sweden)

    Gregory A. Zielinski

    2002-01-01

    Full Text Available Volcanic eruptions have the potential to force global climate, provided they are explosive enough to emit at least 1–5 megaton of sulfur gases into the stratosphere. The sulfuric acid produced during oxidation of these gases will both absorb and reflect incoming solar radiation, thus warming the stratosphere and cooling the Earth’s surface. Maximum global cooling on the order of 0.2–0.3°C, using instrumental temperature records, occurs in the first 2 years after the eruption, with lesser cooling possibly up to the 4th year. Equatorial eruptions are able to affect global climate, whereas mid- to high-latitude events will impact the hemisphere of origin. However, regional responses may differ, including the possibility of winter warming following certain eruptions. Also, El Niño warming may override the cooling induced by volcanic activity. Evaluation of different style eruptions as well as of multiple eruptions closely spaced in time beyond the instrumental record is attained through the analysis of ice-core, tree-ring, and geologic records. Using these data in conjunction with climate proxy data indicates that multiple eruptions may force climate on decadal time scales, as appears to have occurred during the Little Ice Age (i.e., roughly AD 1400s–1800s. The Toba mega-eruption of ~75,000 years ago may have injected extremely large amounts of material into the stratosphere that remained aloft for up to about 7 years. This scenario could lead to the initiation of feedback mechanisms within the climate system, such as cooling of sea-surface temperatures. These interacting mechanisms following a mega-eruption may cool climate on centennial time scales.

  12. Impact of Climate change on Milk production of Murrah buffaloes

    OpenAIRE

    A. Ashutosh; Gupta, S.K.; Kumar, A.(State University of New York at Buffalo, Buffalo, USA); Singh, S. V.; Upadhyay, R. C.

    2010-01-01

    Global warming is likely to impact productivity of buffaloes due to their sensitivity to temperature changes. Air temperature, humidity, wind velocity and solar radiation are the main climate variables that affect buffalo production in tropical climate. In the present study sensitivity of lactating Murrah buffaloes to sudden temperature (Tmax, Tmin) change and THI have been analyzed from milk production and climatic records (1994-2004) of Karnal. Algorithms were developed and validated on lac...

  13. Climate variability and sedimentation of a hydropower reservoir

    International Nuclear Information System (INIS)

    As part of the relicensing of a large Hydroelectric Project in the central Appalachians, large scale watershed and reservoir sedimentation models were developed to forecast potential sedimentation scenarios. The GIS based watershed model was spatially explicit and calibrated to long term observed data. Potential socio/economic development scenarios were used to construct future watershed land cover scenarios. Climatic variability and potential change analysis were used to identify future climate regimes and shifts in precipitation and temperature patterns. Permutations of these development and climate changes were forecasted over 50 years and used to develop sediment yield regimes to the project reservoir. Extensive field work and reservoir survey, including current and wave instrumentation, were used to characterize the project watershed, rivers and reservoir hydrodynamics. A fully 3 dimensional hydrodynamic reservoir sedimentation model was developed for the project and calibrated to observed data. Hydrologic and sedimentation results from watershed forecasting provided boundary conditions for reservoir inputs. The calibrated reservoir model was then used to forecast changes in reservoir sedimentation and storage capacity under different future climate scenarios. Results indicated unique zones of advancing sediment deltas and temporary storage areas. Forecasted changes in reservoir bathymetry and sedimentation patterns were also developed for the various climate change scenarios. The warmer and wetter scenario produced sedimentation impacts similar to extensive development under no climate change. The results of these analyses are being used to develop collaborative watershed and soil conservation partnerships to reduce future soil losses and reservoir sedimentation from projected development. (author)

  14. Climate change and climate variability: personal motivation for adaptation and mitigation

    Directory of Open Access Journals (Sweden)

    Ploubidis George B

    2011-05-01

    Full Text Available Abstract Background Global climate change impacts on human and natural systems are predicted to be severe, far reaching, and to affect the most physically and economically vulnerable disproportionately. Society can respond to these threats through two strategies: mitigation and adaptation. Industry, commerce, and government play indispensable roles in these actions but so do individuals, if they are receptive to behavior change. We explored whether the health frame can be used as a context to motivate behavioral reductions of greenhouse gas emissions and adaptation measures. Methods In 2008, we conducted a cross-sectional survey in the United States using random digit dialing. Personal relevance of climate change from health threats was explored with the Health Belief Model (HBM as a conceptual frame and analyzed through logistic regressions and path analysis. Results Of 771 individuals surveyed, 81% (n = 622 acknowledged that climate change was occurring, and were aware of the associated ecologic and human health risks. Respondents reported reduced energy consumption if they believed climate change could affect their way of life (perceived susceptibility, Odds Ratio (OR = 2.4 (95% Confidence Interval (CI: 1.4 - 4.0, endanger their life (perceived severity, OR = 1.9 (95% CI: 1.1 - 3.1, or saw serious barriers to protecting themselves from climate change, OR = 2.1 (95% CI: 1.2 - 3.5. Perceived susceptibility had the strongest effect on reduced energy consumption, either directly or indirectly via perceived severity. Those that reported having the necessary information to prepare for climate change impacts were more likely to have an emergency kit OR = 2.1 (95% CI: 1.4 - 3.1 or plan, OR = 2.2 (95% CI: 1.5 -3.2 for their household, but also saw serious barriers to protecting themselves from climate change or climate variability, either by having an emergency kit OR = 1.6 (95% CI: 1.1 - 2.4 or an emergency plan OR = 1.5 (95%CI: 1.0 - 2

  15. Climate Changea Impacts and Adaptation Strategies in Kenya

    Institute of Scientific and Technical Information of China (English)

    Patrick Mwendwa; Richard A. Giliba

    2012-01-01

    To determine the climate changes that are due to natural variability and those due to human activities is quite challenging, just like delineating the impacts. Moreover, it is equally difficult to ascertain the adaptive strategies for coping with the climate chang- es and in particular for developing countries like Kenya. While climate change is a global phenomenon, the impacts are more or less specific to local areas such as observed in Kenyan case. There- fore climate change impacts adaptation strategies are appropriately applicable to a given local perspective. The study investigated the main indicators of climate change and effective adaptive strategies that can be employed in Kenya. Based on online questionnaire survey, the study established unpredictable rainfall patterns as the major indicator of climate change in the country, while water harvesting and change of cropping methods are the best adaptive strategies.

  16. Does internal climate variability overwhelm climate change signals in streamflow? The upper Po and Rhone basin case studies

    Energy Technology Data Exchange (ETDEWEB)

    Fatichi, S., E-mail: simone.fatichi@ifu.baug.ethz.ch; Rimkus, S.; Burlando, P.; Bordoy, R.

    2014-09-15

    Projections of climate change effects in streamflow are increasingly required to plan water management strategies. These projections are however largely uncertain due to the spread among climate model realizations, internal climate variability, and difficulties in transferring climate model results at the spatial and temporal scales required by catchment hydrology. A combination of a stochastic downscaling methodology and distributed hydrological modeling was used in the ACQWA project to provide projections of future streamflow (up to year 2050) for the upper Po and Rhone basins, respectively located in northern Italy and south-western Switzerland. Results suggest that internal (stochastic) climate variability is a fundamental source of uncertainty, typically comparable or larger than the projected climate change signal. Therefore, climate change effects in streamflow mean, frequency, and seasonality can be masked by natural climatic fluctuations in large parts of the analyzed regions. An exception to the overwhelming role of stochastic variability is represented by high elevation catchments fed by glaciers where streamflow is expected to be considerably reduced due to glacier retreat, with consequences appreciable in the main downstream rivers in August and September. Simulations also identify regions (west upper Rhone and Toce, Ticino river basins) where a strong precipitation increase in the February to April period projects streamflow beyond the range of natural climate variability during the melting season. This study emphasizes the importance of including internal climate variability in climate change analyses, especially when compared to the limited uncertainty that would be accounted for by few deterministic projections. The presented results could be useful in guiding more specific impact studies, although design or management decisions should be better based on reliability and vulnerability criteria as suggested by recent literature. - Highlights:

  17. Does internal climate variability overwhelm climate change signals in streamflow? The upper Po and Rhone basin case studies

    International Nuclear Information System (INIS)

    Projections of climate change effects in streamflow are increasingly required to plan water management strategies. These projections are however largely uncertain due to the spread among climate model realizations, internal climate variability, and difficulties in transferring climate model results at the spatial and temporal scales required by catchment hydrology. A combination of a stochastic downscaling methodology and distributed hydrological modeling was used in the ACQWA project to provide projections of future streamflow (up to year 2050) for the upper Po and Rhone basins, respectively located in northern Italy and south-western Switzerland. Results suggest that internal (stochastic) climate variability is a fundamental source of uncertainty, typically comparable or larger than the projected climate change signal. Therefore, climate change effects in streamflow mean, frequency, and seasonality can be masked by natural climatic fluctuations in large parts of the analyzed regions. An exception to the overwhelming role of stochastic variability is represented by high elevation catchments fed by glaciers where streamflow is expected to be considerably reduced due to glacier retreat, with consequences appreciable in the main downstream rivers in August and September. Simulations also identify regions (west upper Rhone and Toce, Ticino river basins) where a strong precipitation increase in the February to April period projects streamflow beyond the range of natural climate variability during the melting season. This study emphasizes the importance of including internal climate variability in climate change analyses, especially when compared to the limited uncertainty that would be accounted for by few deterministic projections. The presented results could be useful in guiding more specific impact studies, although design or management decisions should be better based on reliability and vulnerability criteria as suggested by recent literature. - Highlights:

  18. Impacts of climate change on electricity network business

    International Nuclear Information System (INIS)

    Climate has a significant impact on the electricity network business. The electricity network is under the weather pressure all the time and it is planned and constructed to withstand normal climatic stresses. The electricity network that has been planned and constructed now, is expected to be in operation next 40 years. If climatic stresses change in this period, it can cause significant impacts on electricity network business. If the impacts of climate change are figured out in advance, it is possible to mitigate negative points of climate change and exploit the positive points. In this paper the impact of climate change on electricity network business is presented. The results are based on RCAO climate model scenarios. The climate predictions were composed to the period 2016. 2045. The period 1960.1990 was used as a control period. The climate predictions were composed for precipitation, temperature, hoarfrost, thunder, ground frost and wind. The impacts of the change of the climate variables on electricity network business were estimated from technical and economical points of view. The estimation was based on the change predictions of the climate variables. It is expected that climate change will cause more damages than benefits on the electricity network business. The increase of the number of network faults will be the most significant and demanding disadvantage caused by climate change. If networks are not improved to be more resistant for faults, then thunder, heavy snow and wind cause more damages especially to overhead lines in medium voltage network. Increasing precipitation and decreasing amount of ground frost weaken the strength of soil. The construction work will be more difficult with the present vehicles because wet and unfrozen ground can not carry heavy vehicles. As a consequence of increasing temperature, the demand of heating energy will decrease and the demand of cooling energy will increase. This is significant for the electricity

  19. Climate Variability and its Possible Interactions with Water Resources in Central Africa

    OpenAIRE

    Aretouyap Zakari; Njandjock Nouck Philippe; Bisso Dieudonne; Nouayou Robert; Lengue Beatrice; Lepatio Tchieg Alain

    2014-01-01

    The rainfall and temperature variations would produce crucial impacts on water quantity and quality. The Intergovernmental Panel on Climate Change in its fourth report already predicted an eventual warming of 2°C in 2050 for so-called “optimistic” and “median” scenarios. The main objectives of this study were (1) To evaluate the climate variability and its impacts on the water resources in the Central Africa area, (2) To forecast the variability trend for t...

  20. Methodologies for assessing socio-economic impacts of climate change

    International Nuclear Information System (INIS)

    Much of the studies on climate change impacts have focused on physical and biological impacts, yet a knowledge of the social and economic impacts of climate change is likely to have a greater impact on the public and on policymakers. A conventional assessment of the impacts of climate change begins with scenarios of future climate, commonly derived from global climate models translated to a regional scale. Estimates of biophysical conditions provided by such scenarios provide a basis for analyses of human impacts, usually considered sector by sector. The scenario approach, although having considerable merit and appeal, has some noteworthy limitations. It encourages consideration of only a small set of scenarios, requires bold assumptions to be made about adjustments in human systems, provides little direct analysis of sensitivities of human social and economic systems to climate perturbations, and usually invokes the assumption that all factors other than climate are stable and have no synergistic effects on human systems. Conventional studies concentrate on average climate, yet climate is inherently variable. A common response to this situation is to propose further development of climate models, but this is not a sufficient or necessary condition for good and useful assessments of impacts on human activities. Different approaches to socioeconomic impact analysis are needed, and approaches should be considered that include identification of sensitivities in a social or ecological system, identification of critical threshold levels or critical speeds of change in variables, and exploration of alternative methodologies such as process studies, spatial and temporal analogues, and socio-economic systems modelling. 5 refs., 3 figs

  1. Impact of synoptic weather patterns and inter-decadal climate variability on air quality in the North China Plain during 1980-2013

    Science.gov (United States)

    Zhang, Yang; Ding, Aijun; Mao, Huiting; Nie, Wei; Zhou, Derong; Liu, Lixia; Huang, Xin; Fu, Congbin

    2016-01-01

    Potential relationships between air quality, synoptic weather patterns, and the East Asian Monsoon (EAM) over the North China Plain (NCP) were examined during the time period of 1980-2013 using a weather typing technique and ground-based air pollution index (API) data from three cities: Beijing, Tianjin and Shijiazhuang. Using the Kirchhofer method, circulation patterns during the 34-yr study period were classified into 5 categories, which were further used to understand the quantitative relationship between weather and air quality in NCP. The highest API values were associated with a stagnant weather condition when wide-spread stable conditions controlled most part of NCP, while westerly and southerly wind flowed over the northern and eastern part of this region, resulting in both the regional transport and local build-up of air pollutants. Under the continuous control of this weather pattern, API values were found to increase at a rate of 8.5 per day on average. Based on the qualitative and quantitative analysis, a significant correlation was found between the strength of EAM and inter-annual variability of frequencies of the weather patterns. The strengthening of summer/winter monsoon could increase the frequency of occurrence of cyclone/anticyclone related weather patterns. Time series of climate-induced variability in API over the 34 years were reconstructed based on the quantitative relationship between API and predominant weather patterns during 2001-2010. Significant connections between EAM and reconstructed API were found on both the inter-annual and inter-decadal scales. In winter and summer, strengthening/weakening of EAM, which was generally associated with the change of the representative circulation patterns, could improve/worsen air quality in this region.

  2. Climatic variability and human impact during the last 2000 years in western Mesoamerica: evidences of late Classic and Little Ice Age drought events

    Directory of Open Access Journals (Sweden)

    A. Rodríguez-Ramírez

    2015-05-01

    Full Text Available Results are presented from biological (diatoms and ostracodes and non-biological (Ti, Ca/Ti, total inorganic carbon, magnetic susceptibility proxy analyses from an 8.8 m long laminated, high resolution (~20 yr sample−1 sediment sequence from lake Santa María del Oro (SMO, in western Mexico. This lake is at a sensitive location between the dry climates of northern Mexico, under the influence of the north Pacific High Pressure Subtropical Cell and the moister climates of central Mexico, under the influence of the seasonal migration of the Intertropical Convergence Zone and the North American Monsoon (NAM. The sequence covers that last 2000 years and gives evidence of two periods of human impact in the lake, shown by increases in Achnanthidium minutissimum, the first related with the Shaft and Chamber Tombs Cultural Tradition from 100 BC to AD 300 and a second late Postclassic occupation from AD 1100 to 1300. Both periods correspond to relatively wet conditions. The sequence also gives evidence of three dry intervals with high carbonates, ostracodes and aerophilous Eolimna minima concentrations. The first, from AD 500 to 1000 (most intense from AD 600 to 800, correlates with the end of the Shaft and Chamber Tradition after ca. AD 600. This late Classic dry period is the most important climatic signal for the Mesoamerican region during the last 2000 years, as it has been recorded at several sites from Yucatan to the Pacific coast. In the Yucatan area this dry interval has been related with the demise of the Maya culture between AD 850 and 950. The last two dry events correspond with the onset and late Little Ice Age (1400 to 1550 and 1690 to 1770, and follow the Spörer and Maunder minima in solar radiation. The first of these intervals (1400–1550 shows the most intense signal over western Mexico, however this pattern changes at other sites. Dry/wet intervals in the SMO record are related with lower/higher intensity of the NAM over this region.

  3. Can climate variability contribute to the ``missing'' CO2 sink?

    Science.gov (United States)

    Dai, Aiguo; Fung, Inez Y.

    1993-09-01

    The contemporary carbon budget for the atmosphere requires a large "missing" carbon sink to balance anthropogenic carbon inputs. We investigated climatic effects on carbon exchanges between the atmosphere and the undisturbed biosphere and assessed the possible contribution of climate variability to the carbon sink. Empirical models and global temperature and precipitation data sets were used in the study. It was found that climate perturbations during 1940-1988 caused considerable variations in plant productivity and soil respiration. The different sensitivities of the fluxes to climate perturbations led to a significant carbon accumulation in the biosphere. The cumulative carbon sink for the period 1950-1984 (˜20±5 GtC or 1012 kg C) was predominantly located in mid-latitudes in the northern hemisphere (30°-60°N) and could amount to half of the missing CO2 sink as derived from deconvolution analyses. Our results indicate that climate variations have unequal impacts on biospheric carbon fluxes from different ecosystems and imply that caution must be exercised in generalizing in situ observations to the globe.

  4. An attempt to assess the energy related climate variability

    Energy Technology Data Exchange (ETDEWEB)

    Iotova, A. [Bulgarian Academy of Sciences, Sofia (Bulgaria). National Inst. of Meteorology and Hydrology

    1995-12-31

    A lot of efforts are directed now to study the interactions between energy and climate because of their significant importance for our planet. Globally, energy related emissions of Greenhouse Gases (GHGs) contribute for atmospheric warming. On regional level, where it is more difficult to determine concrete direction of climate variability and change, the role of energy remains considerable being not so direct as in the case of emissions` impact. Still there is essential necessity for further analyses and assessments of energy related climate variations and change in order to understand better and to quantify the energy - climate relations. In the presentation an attempt is made to develop approach for assessment of energy related climate variations on regional level. For this purpose, data and results from the research within Bulgarian Case Study (BCS) in the DECADES Inter-Agency Project framework are used. Considering the complex nature of the examined interconnections and the medium stage of the Study`s realisation, at the moment the approach can be presented in conceptual form. Correspondingly, the obtained results are illustrative and preliminary

  5. Climate variability of the tropical Andes since the late Pleistocene

    Directory of Open Access Journals (Sweden)

    A. Bräuning

    2009-10-01

    Full Text Available Available proxy records witnessing palaeoclimate of the tropical Andes are comparably scarce. Major implications of palaeoclimate development in the humid and arid parts of the Andes are briefly summarized. The long-term behaviour of ENSO has general significance for the climatic history of the Andes due to its impact on regional circulation patterns and precipitation regimes, therefore ENSO history derived from non-Andean palaeo-records is highlighted. Methodological constraints of the chronological precision and the palaeoclimatic interpretation of records derived from different natural archives, such as glacier sediments and ice cores, lake sediments and palaeo-wetlands, pollen profiles and tree rings are addressed and complementary results concerning former climatic conditions are discussed in terms of possible implications of former atmospheric circulation patterns and main climatic forcing factors. During the last years, increasing tree-ring information is getting available from the tropical Andes, providing high-resolution climate-sensitive records covering the past centuries for the study of climate variability.

  6. The effects of solar variability on climate

    International Nuclear Information System (INIS)

    It has been hypothesized for at least a century that some of the observed variance in global temperature records arises from variations in solar output. Theories of solar-variability effects on climate could not be tested directly prior to satellite measurements because uncertainties in ground-based measurements of solar irradiance were larger than the solar variations themselves. Measurements by the Active Cavity Radiometer (ACRIM) onboard the Solar Max satellite and by the Earth Radiation Budget (ERB) instrument onboard Nimbus 6 are now available which indicate solar-constant variations are positively correlated with solar activity over an 11-yr solar cycle, and are of order ± 1.0 W m-2 relative to a mean solar constant of S0 = 1,367 W m-2, ΔS/S0 ∼ ± 0.07%. For a typical climate sensitivity parameter of β = S0 ∂T/∂S ∼ 100 C, the corresponding variations in radiative equilibrium temperature at the Earth's surface are ΔTe ∼ ± 0.07 C. The realized temperature variations from solar forcing, ΔT, can be significantly smaller because of thermal damping by the ocean. The author considers effects of solar variability on the observed and projected history of the global temperature record in light of this data using an upwelling-diffusion ocean model to assess the effect of ocean thermal inertia on the thermal response. The response to harmonic variations of the 11-yr sunspot cycle is of order ΔT ∼ ± 0.02 C, though the coupling between response and forcing is stronger for long-term variations in the envelope of the solar cycle which more nearly match the thermal response time of the deep ocean

  7. Methods for assessment of climate variability and climate changes in different time-space scales

    International Nuclear Information System (INIS)

    Main problem of hydrology and design support for water projects connects with modern climate change and its impact on hydrological characteristics as observed as well as designed. There are three main stages of this problem: - how to extract a climate variability and climate change from complex hydrological records; - how to assess the contribution of climate change and its significance for the point and area; - how to use the detected climate change for computation of design hydrological characteristics. Design hydrological characteristic is the main generalized information, which is used for water management and design support. First step of a research is a choice of hydrological characteristic, which can be as a traditional one (annual runoff for assessment of water resources, maxima, minima runoff, etc) as well as a new one, which characterizes an intra-annual function or intra-annual runoff distribution. For this aim a linear model has been developed which has two coefficients connected with an amplitude and level (initial conditions) of seasonal function and one parameter, which characterizes an intensity of synoptic and macro-synoptic fluctuations inside a year. Effective statistical methods have been developed for a separation of climate variability and climate change and extraction of homogeneous components of three time scales from observed long-term time series: intra annual, decadal and centural. The first two are connected with climate variability and the last (centural) with climate change. Efficiency of new methods of decomposition and smoothing has been estimated by stochastic modeling and well as on the synthetic examples. For an assessment of contribution and statistical significance of modern climate change components statistical criteria and methods have been used. Next step has been connected with a generalization of the results of detected climate changes over the area and spatial modeling. For determination of homogeneous region with the same

  8. Disaster management, climate change and variability and social resilience

    OpenAIRE

    O'Brien, Geoff

    2008-01-01

    Disaster Management, Climate Change and Variability and Social Resilience Abstract Accelerated climate change and increasing climate variability caused by increasing anthropogenic greenhouse gas emissions is the single largest threat to the international goals of sustainable development, the Millennium Development Goals (MDGs) and disaster risk reduction. Global discourses recognise the need for effective and sustainable responses to produced climate risks. The risk types likely to occur are ...

  9. Climate variation explains a third of global crop yield variability

    OpenAIRE

    Ray, Deepak K.; James S Gerber; MacDonald, Graham K.; West, Paul C.

    2015-01-01

    Many studies have examined the role of mean climate change in agriculture, but an understanding of the influence of inter-annual climate variations on crop yields in different regions remains elusive. We use detailed crop statistics time series for ~13,500 political units to examine how recent climate variability led to variations in maize, rice, wheat and soybean crop yields worldwide. While some areas show no significant influence of climate variability, in substantial areas of the global b...

  10. Sea-Level climate variability in the Mediterranean Sea

    OpenAIRE

    Bonaduce, Antonio

    2012-01-01

    Sea-level variability is characterized by multiple interacting factors described in the Fourth Assessment Report (Bindoff et al., 2007) of the Intergovernmental Panel on Climate Change (IPCC) that act over wide spectra of temporal and spatial scales. In Church et al. (2010) sea-level variability and changes are defined as manifestations of climate variability and change. The European Environmental Agency (EEA) defines sea level as one of most important indicators for monitoring climate chan...

  11. Climate change impacts on US agriculture and forestry: benefits of global climate stabilization

    Science.gov (United States)

    Beach, Robert H.; Cai, Yongxia; Thomson, Allison; Zhang, Xuesong; Jones, Russell; McCarl, Bruce A.; Crimmins, Allison; Martinich, Jeremy; Cole, Jefferson; Ohrel, Sara; DeAngelo, Benjamin; McFarland, James; Strzepek, Kenneth; Boehlert, Brent

    2015-09-01

    Increasing atmospheric carbon dioxide levels, higher temperatures, altered precipitation patterns, and other climate change impacts have already begun to affect US agriculture and forestry, with impacts expected to become more substantial in the future. There have been numerous studies of climate change impacts on agriculture or forestry, but relatively little research examining the long-term net impacts of a stabilization scenario relative to a case with unabated climate change. We provide an analysis of the potential benefits of global climate change mitigation for US agriculture and forestry through 2100, accounting for landowner decisions regarding land use, crop mix, and management practices. The analytic approach involves a combination of climate models, a crop process model (EPIC), a dynamic vegetation model used for forests (MC1), and an economic model of the US forestry and agricultural sector (FASOM-GHG). We find substantial impacts on productivity, commodity markets, and consumer and producer welfare for the stabilization scenario relative to unabated climate change, though the magnitude and direction of impacts vary across regions and commodities. Although there is variability in welfare impacts across climate simulations, we find positive net benefits from stabilization in all cases, with cumulative impacts ranging from 32.7 billion to 54.5 billion over the period 2015-2100. Our estimates contribute to the literature on potential benefits of GHG mitigation and can help inform policy decisions weighing alternative mitigation and adaptation actions.

  12. Climate change impacts on US agriculture and forestry: benefits of global climate stabilization

    Energy Technology Data Exchange (ETDEWEB)

    Beach, Robert H.; Cai, Yongxia; Thomson, Allison M.; Zhang, Xuesong; Jones, Russ; McCarl, Bruce A.; Crimmins, Allison; Martinich, Jeremy; Cole, Jefferson; Ohrel, Sara; DeAngelo, B. J.; McFarland, Jim; Strzepek, K.; Boehlert, Brent

    2015-09-01

    Increasing atmospheric carbon dioxide levels, higher temperatures, altered precipitation patterns, and other climate change impacts have already begun to affect US agriculture and forestry, with impacts expected to become more substantial in the future. There have been numerous studies of climate change impacts on agriculture or forestry, but relatively little research examining the long-term net impacts of a stabilization scenario relative to a case with unabated climate change. We provide an analysis of the potential benefits of global climate change mitigation for US agriculture and forestry through 2100, accounting for landowner decisions regarding land use, crop mix, and management practices. The analytic approach involves a combination of climate models, a crop process model (EPIC), a dynamic vegetation model used for forests (MC1), and an economic model of the US forestry and agricultural sector (FASOM-GHG). We find substantial impacts on productivity, commodity markets, and consumer and producer welfare for the stabilization scenario relative to unabated climate change, though the magnitude and direction of impacts vary across regions and commodities. Although there is variability in welfare impacts across climate simulations, we find positive net benefits from stabilization in all cases, with cumulative impacts ranging from $32.7 billion to $54.5 billion over the period 2015-2100. Our estimates contribute to the literature on potential benefits of GHG mitigation and can help inform policy decisions weighing alternative mitigation and adaptation actions.

  13. Climate Change and Climate Variability in the Latin American Region

    Science.gov (United States)

    Magrin, G. O.; Gay Garcia, C.; Cruz Choque, D.; Gimenez-Sal, J. C.; Moreno, A. R.; Nagy, G. J.; Nobre, C.; Villamizar, A.

    2007-05-01

    Over the past three decades LA was subjected to several climate-related impacts due to increased El Niño occurrences. Two extremely intense episodes of El Niño and other increased climate extremes happened during this period contributing greatly to augment the vulnerability of human systems to natural disasters. In addition to weather and climate, the main drivers of the increased vulnerability are demographic pressure, unregulated urban growth, poverty and rural migration, low investment in infrastructure and services, and problems in inter-sector coordination. As well, increases in temperature and increases/decreases in precipitation observed during the last part of 20th century have yet led to intensification of glaciers melting, increases in floods/droughts and forest fires frequency, increases in morbidity and mortality, increases in plant diseases incidence; lost of biodiversity, reduction in dairy cattle production, and problems with hydropower generation, highly affecting LA human system. For the end of the 21st century, the projected mean warming for LA ranges from 1 to 7.5ºC and the frequency of weather and climate extremes could increase. Additionally, deforestation is projected to continue leading to a reduction of 25 percent in Amazonia forest in 2020 and 40 percent in 2050. Soybeans planted area in South America could increase by 55 percent by 2020 enhancing aridity/desertification in many of the already water- stressed regions. By 2050 LA population is likely to be 50 percent larger than in 2000, and migration from the country sides to the cities will continue. In the near future, these predicted changes are very likely to severely affect a number of ecosystems and sectors distribution; b) Disappearing most tropical glaciers; c) Reducing water availability and hydropower generation; d) Increasing desertification and aridity; e) Severely affecting people, resources and economic activities in coastal areas; f) Increasing crop's pests and diseases

  14. Impacts of Climate Change on Brazilian Agriculture : Refocusing Impact Assessments to 2050

    OpenAIRE

    World Bank, (WB)

    2010-01-01

    This report evaluates the requirements for an assessment of climate change impacts on agriculture to guide policy makers on investment priorities and phasing. Because agriculture is vital for national food security and is a strong contributor to Brazil's GDP growth, there is growing concern that Brazilian agriculture is increasingly vulnerable to climate variability and change. To meet nat...

  15. Linking the uncertainty of low frequency variability in tropical forcing in regional climate change

    Energy Technology Data Exchange (ETDEWEB)

    Forest, Chris E. [The Pennsylvania State University; Barsugli, Joseph J. [Cooperative Institute for Research in Environmental Sciences (CIRES) at the University of Colorado at Boulder and NOAA Earth Systems Research Laboratory; Li, Wei [The Pennsylvania State University

    2015-02-20

    The project utilizes multiple atmospheric general circulation models (AGCMs) to examine the regional climate sensitivity to tropical sea surface temperature forcing through a series of ensemble experiments. The overall goal for this work is to use the global teleconnection operator (GTO) as a metric to assess the impact of model structural differences on the uncertainties in regional climate variability.

  16. Saharan dust, climate variability, and asthma in Grenada, the Caribbean

    Science.gov (United States)

    Akpinar-Elci, Muge; Martin, Francis E.; Behr, Joshua G.; Diaz, Rafael

    2015-11-01

    Saharan dust is transported across the Atlantic and interacts with the Caribbean seasonal climatic conditions, becoming respirable and contributing to asthma presentments at the emergency department. This study investigated the relationships among dust, climatic variables, and asthma-related visits to the emergency room in Grenada. All asthma visits to the emergency room ( n = 4411) over 5 years (2001-2005) were compared to the dust cover and climatic variables for the corresponding period. Variation in asthma was associated with change in dust concentration ( R 2 = 0.036, p asthma was positively correlated with rainfall ( R 2 = 0.055, p asthma visits were inversely related to mean sea level pressure ( R 2 = 0.123, p = 0.006) and positively correlated with relative humidity ( R 2 = 0.593, p = 0.85). Saharan dust in conjunction with seasonal humidity allows for inhalable particulate matter that exacerbates asthma among residents in the Caribbean island of Grenada. These findings contribute evidence suggesting a broader public health impact from Saharan dust. Thus, this research may inform strategic planning of resource allocation among the Caribbean public health agencies.

  17. Climate Variability and Phytoplankton in the Pacific Ocean

    Science.gov (United States)

    Rousseaux, Cecile

    2012-01-01

    The effect of climate variability on phytoplankton communities was assessed for the tropical and sub-tropical Pacific Ocean between 1998 and 2005 using an established biogeochemical assimilation model. The phytoplankton communities exhibited wide range of responses to climate variability, from radical shifts in the Equatorial Pacific, to changes of only a couple of phytoplankton groups in the North Central Pacific, to no significant changes in the South Pacific. In the Equatorial Pacific, climate variability dominated the variability of phytoplankton. Here, nitrate, chlorophyll and all but one of the 4 phytoplankton types (diatoms, cyanobacteria and coccolithophores) were strongly correlated (pclimate variability can play in ocean biology.

  18. Incorporating climate change trends to near future variability of crop yields in Iberia Peninsula

    Science.gov (United States)

    Capa-Morocho, Mirian; Baethgen, Walter E.; Fernandes, Kátia; Rodríguez-Fonseca, Belén; Ruiz-Ramos, Margarita

    2016-04-01

    In this study, we analyze the effects of near future climate variability on cropping systems in Iberian Peninsula (IP). For this purpose, we generated climate sequences that simulate realistic variability on annual to decadal time scales. The sequences incorporate nonlinear climate change trends, using statistical methods and and an ensemble of global climate models from the Coupled Model Intercomparison Project (CMIP5). Then, the climate sequences are temporal downscaled into daily weather data and used as inputs to crop models. As case study, we evaluate the impacts of plausible future climate scenarios on rain-fed wheat yield two agricultural locations in IP. We adapted the method by Greene et al., (2012 and 2015) for informing climate projections for the coming decades with a combination of seasonal to interannual and anthropogenically forced climate change information for accounting the Near-term Climate Change. Long-term data containing solar radiation, maximum and minimum temperature and rainfall are needed to apply this method. The climate variability observed was decomposed into long-range trend, decadal and interannual variability to understand the relative importance of each time scale. The interannual variability was modeled based on the observational records. The results of this study may have important implications on public and private sectors to analyze the probabilistic projections of impacts and agronomic adaptations of near future climate variability in Iberian Peninsula. This study has been funded by MACSUR project from FACCE-JPI. References Greene, A.M., Goddard, L., Gonzalez, P.L., Ines, A.V. and Chryssanthacopoulos, J., 2015.A climate generator for agricultural planning in southeastern South America.Agricultural and Forest Meteorology, 203: 217-228. Greene, A.M., Hellmuth, M. and Lumsden, T., 2012. Stochastic decadal climate simulations for the Berg and Breede water management areas, western Cape province, South Africa. Water Resources

  19. Climate variability and sedimentation of a hydropower reservoir

    International Nuclear Information System (INIS)

    This presentation discussed a large-scale watershed and reservoir sedimentation model developed to predict potential sedimentation scenarios for a large hydroelectric power project located in the central Appalachians. The geographic information system (GIS) watershed model was calibrated using observed long-term meteorological and hydrological data. Potential development scenarios were then used to construct future watershed land cover scenarios. Future climate change regimes and precipitation and temperature pattern shifts were identified using climatic variability and potential change analyses. Results of the study were then forecast for a period of 50 years and used to develop sediment yield regimes for the project's reservoir. The model was validated using reservoir and fields studies for watershed, river, and reservoir hydrodynamics. The resulting 3-D hydrological sedimentation model was then used to forecast changes in river sedimentation and storage capacity under various future climate scenarios. Results of the study showed the development of unique zones of advancing sediment deltas and temporary storage areas. Warmer and wetter scenarios produced sedimentation impacts similar to scenarios without climatic change. It was concluded that results of the analyses will be used to help reduce future soil losses in the reservoir. tabs., figs

  20. Putting climate impact estimates to work: the empirical approach of the American Climate Prospectus

    Science.gov (United States)

    Jina, A.; Hsiang, S. M.; Kopp, R. E., III; Rasmussen, D.; Rising, J.

    2014-12-01

    The American Climate Prospectus (ACP), the technical analysis underlying the Risky Business project, quantitatively assesses climate risks posed to the United States' economy in a number of sectors [1]. Four of these - crop yield, crime, labor productivity, and mortality - draw upon research which identifies social impacts using contemporary variability in climate. We first identify a group of rigorous studies that use climate variability to identify responses to temperature and precipitation, while controlling for unobserved differences between locations. To incorporate multiple studies from a single sector, we employ a meta-analytical approach that draws on Bayesian methods commonly used in medical research and previously implemented in [2]. We generate a series of aggregate response functions for each sector using this meta-analytical method. We combine response functions with downscaled physical climate projections to estimate climate impacts out to the end of the century, incorporating uncertainty from statistical estimates, weather, climate models, and different emissions scenarios. Incorporating multiple studies in a single estimation framework allows us to directly compare impacts across the economy. We find that increased mortality has the largest effect on the US economy, followed by costs associated with decreased labor productivity. Agricultural losses and increases in crime contribute lesser but nonetheless substantial costs, and agriculture, notably, shows many areas benefitting from projected climate changes. The ACP also presents results throughout the 21stcentury. The dynamics of each of the impact categories differs, with, for example, mortality showing little change until the end of the century, but crime showing a monotonic increase from the present day. The ACP approach can expand to include new findings in current sectors, new sectors, and new geographical areas of interest. It represents an analytical framework that can incorporate empirical

  1. Climatic history - answers on the variability of weather and climate?

    International Nuclear Information System (INIS)

    The paper is concerned with various aspects of climatic history. Emphasis is on the spectrum of data and methods used in historical climatology. The following section is devoted to an outline of the short- and long-range climatic changes since 1500 A.D. that show how much the climate has varied in space and time. It is pointed out that climatic extremes have been an ever-recurrent phenomenon throughout history. (orig.)

  2. Hydro-climatic variability over the Andes of Colombia associated with ENSO: a review of climatic processes and their impact on one of the Earth's most important biodiversity hotspots

    Energy Technology Data Exchange (ETDEWEB)

    Poveda, German; Alvarez, Diana M. [Universidad Nacional de Colombia, School of Geosciences and Environment, Medellin (Colombia); Rueda, Oscar A. [Universidad Nacional de Colombia, School of Geosciences and Environment, Medellin (Colombia); Grupo HTM, Medellin (Colombia)

    2011-06-15

    The hydro-climatic variability of the Colombian Andes associated with El Nino-Southern Oscillation (ENSO) is reviewed using records of rainfall, river discharges, soil moisture, and a vegetation index (NDVI) as a surrogate for evapotranspiration. Anomalies in the components of the surface water balance during both phases of ENSO are quantified in terms of their sign, timing, and magnitude. During El Nino (La Nina), the region experiences negative (positive) anomalies in rainfall, river discharges (average and extremes), soil moisture, and NDVI. ENSO's effects are phase-locked to the seasonal cycle, being stronger during December-February, and weaker during March-May. Besides, rainfall and river discharges anomalies show that the ENSO signal exhibits a westerly wave-like propagation, being stronger (weaker) and earlier (later) over the western (eastern) Andes. Soil moisture anomalies are land-cover type dependant, but overall they are enhanced by ENSO, showing very low values during El Nino (mainly during dry seasons), but saturation values during La Nina. A suite of large-scale and regional mechanisms cooperating at the ocean-atmosphere-land system are reviewed to explaining the identified hydro-climatic anomalies. This review contributes to an understanding of the hydro-climatic framework of a region identified as the most critical hotspot for biodiversity on Earth, and constitutes a wake-up call for scientists and policy-makers alike, to take actions and mobilize resources and minds to prevent the further destruction of the region's valuable hydrologic and biodiversity resources and ecosystems. It also sheds lights towards the implementation of strategies and adaptation plans to coping with threats from global environmental change. (orig.)

  3. Hydro-climatic variability over the Andes of Colombia associated with ENSO: a review of climatic processes and their impact on one of the Earth's most important biodiversity hotspots

    Science.gov (United States)

    Poveda, Germán; Álvarez, Diana M.; Rueda, Óscar A.

    2011-06-01

    The hydro-climatic variability of the Colombian Andes associated with El Niño-Southern Oscillation (ENSO) is reviewed using records of rainfall, river discharges, soil moisture, and a vegetation index (NDVI) as a surrogate for evapotranspiration. Anomalies in the components of the surface water balance during both phases of ENSO are quantified in terms of their sign, timing, and magnitude. During El Niño (La Niña), the region experiences negative (positive) anomalies in rainfall, river discharges (average and extremes), soil moisture, and NDVI. ENSO's effects are phase-locked to the seasonal cycle, being stronger during December-February, and weaker during March-May. Besides, rainfall and river discharges anomalies show that the ENSO signal exhibits a westerly wave-like propagation, being stronger (weaker) and earlier (later) over the western (eastern) Andes. Soil moisture anomalies are land-cover type dependant, but overall they are enhanced by ENSO, showing very low values during El Niño (mainly during dry seasons), but saturation values during La Niña. A suite of large-scale and regional mechanisms cooperating at the ocean-atmosphere-land system are reviewed to explaining the identified hydro-climatic anomalies. This review contributes to an understanding of the hydro-climatic framework of a region identified as the most critical hotspot for biodiversity on Earth, and constitutes a wake-up call for scientists and policy-makers alike, to take actions and mobilize resources and minds to prevent the further destruction of the region's valuable hydrologic and biodiversity resources and ecosystems. It also sheds lights towards the implementation of strategies and adaptation plans to coping with threats from global environmental change.

  4. The economic impact of climate change on Kenyan crop agriculture : a ricardian approach

    OpenAIRE

    Kabubo-Mariara, Jane; Karanja, Fredrick K

    2007-01-01

    This paper measures the economic impact of climate on crops in Kenya. The analysis is based on cross-sectional climate, hydrological, soil, and household level data for a sample of 816 households, and uses a seasonal Ricardian model. Estimated marginal impacts of climate variables suggest that global warming is harmful for agricultural productivity and that changes in temperature are much ...

  5. The Economic Impact of Climate Change

    OpenAIRE

    TOL, Richard S.J.

    2008-01-01

    I review the literature on the economic impacts of climate change, an externality that is unprecedentedly large, complex, and uncertain. Only 14 estimates of the total damage cost of climate change have been published, a research effort that is in sharp contrast to the urgency of the public debate and the proposed expenditure on greenhouse gas emission reduction. These estimates show that climate change initially improves economic welfare. However, these benefits are sunk. Impacts would be pr...

  6. Transport impacts on atmosphere and climate: Aviation

    OpenAIRE

    Lee, D. S.; G. Pitari; V. Grewe; Gierens, K.; Penner, J. E.; A. Petzold; Prather, M. J.; Schumann, U.; Bais, A.; T. Berntsen; Iachetti, D; Lim, L. L.; Sausen, R.

    2010-01-01

    Aviation alters the composition of the atmosphere globally and can thus drive climate change and ozone depletion. The last major international assessment of these impacts was made by the Intergovernmental Panel on Climate Change (IPCC) in 1999. Here, a comprehensive updated assessment of aviation is provided. Scientific advances since the 1999 assessment have reduced key uncertainties, sharpening the quantitative evaluation, yet the basic conclusions remain the same. The climate impact of avi...

  7. Understanding climate variability and change in the Altiplano

    OpenAIRE

    Seth, Anji

    2007-01-01

    This presentation addresses climate variability in the climate change models for 20th and 21st centuries for the Altiplano Region. The models appear to simulate this mechanism in the present, but respond quite differently in 21st century climate. This poses a question: Is this related to LTRA-4 (Practices and Strategies for Vulnerable Agro-Ecosystems)

  8. The value of seasonal forecasting and crop mix adaptation to climate variability for agriculture under climate change

    Science.gov (United States)

    Choi, H. S.; Schneider, U.; Schmid, E.; Held, H.

    2012-04-01

    Changes to climate variability and frequency of extreme weather events are expected to impose damages to the agricultural sector. Seasonal forecasting and long range prediction skills have received attention as an option to adapt to climate change because seasonal climate and yield predictions could improve farmers' management decisions. The value of seasonal forecasting skill is assessed with a crop mix adaptation option in Spain where drought conditions are prevalent. Yield impacts of climate are simulated for six crops (wheat, barely, cotton, potato, corn and rice) with the EPIC (Environmental Policy Integrated Climate) model. Daily weather data over the period 1961 to 1990 are used and are generated by the regional climate model REMO as reference period for climate projection. Climate information and its consequent yield variability information are given to the stochastic agricultural sector model to calculate the value of climate information in the agricultural market. Expected consumers' market surplus and producers' revenue is compared with and without employing climate forecast information. We find that seasonal forecasting benefits not only consumers but also producers if the latter adopt a strategic crop mix. This mix differs from historical crop mixes by having higher shares of crops which fare relatively well under climate change. The corresponding value of information is highly sensitive to farmers' crop mix choices.

  9. Sensitivity of water scarcity events to ENSO driven climate variability at the global scale

    OpenAIRE

    T. I. E. Veldkamp; Eisner, S.; Wada, Y.; J. C. J. H. Aerts; P. J. Ward

    2015-01-01

    Globally, freshwater shortage is one of the most important risks for society. Changing hydro-climatic and socioeconomic conditions have aggravated water scarcity over the past decades. A wide range of studies show that water scarcity will intensify in the future, as a result of both increased consumptive water use and in some regions climate change However, less attention has been paid to the impacts of climate variability on water scarcit...

  10. Possible Impacts of Climate Change on Mediterranean Irrigated Farming Systems

    OpenAIRE

    Dono, Gabriele; Cortignani, Raffaele; Doro, Luca; Ledda, Luigi; Roggero, PierPaolo; Giraldo, Luca; Severini, Simone

    2011-01-01

    In the agricultural sector, climate change (CC) affects multiple weather variables at different stages of crop cycles. CC may influence the mean level or affect the distribution of events (e.g., rainfall, temperature). This work evaluates the economic impact of CC-related changes in multiple climatic components, and the resulting uncertainty. For this purpose, a three-stage discrete stochastic programming model is used to represents farm sector of an irrigated area of Italy and to examine the...

  11. Climate impact from peat utilisation in Sweden

    International Nuclear Information System (INIS)

    The climate impact from the use of peat for energy production in Sweden has been evaluated in terms of contribution to atmospheric radiative forcing. This was done by attempting to answer the question 'What will be the climate impact if one would use 1 m2 of mire for peat extraction during 20 years?'. Two different methods of after-treatment were studied: afforestation and restoration of wetland. The climate impact from a peatland - wetland energy scenario and a peatland - forestry energy scenario was compared to the climate impact from coal, natural gas and forest residues. Sensitivity analyses were performed to evaluate which parameters that are important to take into consideration in order to minimize the climate impact from peat utilisation

  12. Detection of trends in surface ozone in the presence of climate variability

    Science.gov (United States)

    Barnes, Elizabeth A.; Fiore, Arlene M.; Horowitz, Larry W.

    2016-05-01

    Trends in trace atmospheric constituents can be driven not also by trends in their (precursor) emissions but also by trends in meteorology. Here we use ground-level ozone as an example to highlight the extent to which unforced, low-frequency climate variability can drive multidecadal trends. Using output from six experiments of the Geophysical Fluid Dynamics Laboratory chemistry-climate model (CM3), we demonstrate that 20 year trends in surface ozone driven by climate variability alone can be as large as those forced by changes in ozone precursor emissions or by anthropogenic climate change. We highlight regions and seasons where surface ozone is strongly influenced by climate variability and thus where a given forced trend may be more difficult to detect. A corollary is that this approach identifies regions and seasons of low variability, where measurement sites may be most effectively deployed to detect a particular trend driven by changing precursor emissions. We find that the representative concentration pathways 4.5 (RCP4.5) and RCP8.5 forced surface ozone trends in most locations emerge over background variability during the first half of the 21st century. Ozone trends are found to respond mostly to changes in emissions of ozone precursors and unforced climate variability, with a comparatively small impact from anthropogenic climate change. Thus, attempts to attribute observed trends to regional emissions changes require consideration of internal climate variability, particularly for short record lengths and small forced trends.

  13. Assessing the likely impacts of climate change on infrastructure

    International Nuclear Information System (INIS)

    Full text: In 2005, the Victorian Government contracted CSIRO, Maunsell Australia and Phillips Fox to undertake an overview assessment of the likely impacts of climate change on the State's infrastructure, establish the categories of infrastructure most at risk and outline opportunities for adaptation responses. The Government released the assessment in May 2007. Climate change poses a significant risk to infrastructure and its owners, managers and long-term operators. The work was undertaken on the basis that it should not be assumed that future climate and its impacts will simply be an extension of what has been experienced in the past. Major infrastructure items have long useful life spans (20-100 years). A bridge built today is expected to still be in use in tens, if not hundreds, of years. This means that recognition of likely climate change impacts and appropriate adaptation measures should occur now. Recognition of the risks associated with climate change is a valuable first step towards better planning of new infrastructure investments and reducing potential damage to existing infrastructure.lnfrastructure types examined were water, power, telecommunications, transport and buildings. The climate change projections used in this report are based on CSIRO climate modelling, supported by findings from the Intergovernmental Panel on Climate Change. Climatic and other variables considered were temperature, rainfall, available moisture, humidity, winds, fire-weather frequency and intensity, solar radiation levels and sea-level rise. For each climate change variable identified, we described a worst-case impact for low and high climate change projections for the years 2030 and 2070. The assessment was made on the basis of 'business as usual' with no adaptation responses to climate change. The report also details the current governance structures associated with each infrastructure type. Overall, the report assessed the likely impact of climate change on

  14. Wildlife as biological indicators for assessing impacts of climate change

    International Nuclear Information System (INIS)

    Estimates of the impacts of climate change on wildlife are necessarily constrained by knowledge of the effects of climate on wildlife. A review is presented of the better-known impacts of climate on wildlife, examining their utility as ecological indicators. The most obvious feature of any species is its geographic distribution, or range. Climate may affect distribution indirectly through effects on habitat, directly through physiological effects, or most probably, through both. Impacts can include changes in distribution of habitat, changes in distribution of species, and changes in migration routes. Direct effects of climate include timing and success of breeding, timing and success of migration, winter survival, and extreme events. Distribution changes are powerful integrators of ecosystem-level events, but poor indicators of particular changes. Changes in the timing of migration, and the phenology of breeding, are more directly determined by weather events and hence will be better indicators of changing climate. Detailed knowledge of effects of climate on timing and success of breeding is available for only a few species, and has not been carefully synthesized with a view to using such variables as climatic indicators. Temperature maxima and minima, frost-free and degree days, and estimates of precipitation on finer scales, both temporal and geographic, are needed to predict the effects of climate change on wildlife. 48 refs

  15. The impact of climate change on hydro-electricity generation

    International Nuclear Information System (INIS)

    Hydropower is the leading source of electrical production in many countries. It is a clean and renewable source and certainly will continue to play an important role in the future energy supply. However, the effects of climate change on this valuable resource remain questionable. In order to identify the potential initiatives that the hydropower industry may undertake, it is important to determine the current state of knowledge of the impacts of climate change on hydrological variables at regional and local scales. Usually, the following steps are taken. First, general circulation models (GCMs) are used to simulate future climate under assumed greenhouse gas emission scenarios. Then, different techniques (statistical downscaling/regional climate models) are applied to downscale the GCM outputs to the appropriate scales of hydrological models. Finally, hydrologic models are employed to simulate the effects of climate change at regional and local scales. Outputs from these models serve as inputs to water management models that give more details about hydropower production. In the present study, realized by OURANOS upon the request of CEATI, a critical review of the methods used to determine impact of climate change on water resources and hydropower generation is carried out. The major results from recent studies worldwide are reported and future scientific actions to better understand climate change impacts on the hydrological regime are identified. The study is expected to provide direction for the hydropower industry to mitigate the impacts of climate change. (author)

  16. Present and Future Modes of Low Frequency Climate Variability

    Energy Technology Data Exchange (ETDEWEB)

    Cane, Mark A.

    2014-02-20

    This project addressed area (1) of the FOA, “Interaction of Climate Change and Low Frequency Modes of Natural Climate Variability”. Our overarching objective is to detect, describe and understand the changes in low frequency variability between model simulations of the preindustrial climate and simulations of a doubled CO2 climate. The deliverables are a set of papers providing a dynamical characterization of interannual, decadal, and multidecadal variability in coupled models with attention to the changes in this low frequency variability between pre-industrial concentrations of greenhouse gases and a doubling of atmospheric concentrations of CO2. The principle mode of analysis, singular vector decomposition, is designed to advance our physical, mechanistic understanding. This study will include external natural variability due to solar and volcanic aerosol variations as well as variability internal to the climate system. An important byproduct is a set of analysis tools for estimating global singular vector structures from the archived output of model simulations.

  17. An empirical economic assessment of impacts of climate change on agriculture in Zambia

    OpenAIRE

    Jain, Suman

    2007-01-01

    This report assesses the economic impacts of climate change on agriculture in Zambia, using the Ricardian method. A multiple linear regression model with net revenue per hectare as response variable has been fitted with climate, hydrological, soil, and socioeconomic variables as explanatory variables. There is one main cropping season in Zambia, lasting from November to April. Crop product...

  18. Predicting the Impacts of Climate Change on Central American Agriculture

    Science.gov (United States)

    Winter, J. M.; Ruane, A. C.; Rosenzweig, C.

    2011-12-01

    Agriculture is a vital component of Central America's economy. Poor crop yields and harvest reliability can produce food insecurity, malnutrition, and conflict. Regional climate models (RCMs) and agricultural models have the potential to greatly enhance the efficiency of Central American agriculture and water resources management under both current and future climates. A series of numerical experiments was conducted using Regional Climate Model Version 3 (RegCM3) and the Weather Research and Forecasting Model (WRF) to evaluate the ability of RCMs to reproduce the current climate of Central America and assess changes in temperature and precipitation under multiple future climate scenarios. Control simulations were thoroughly compared to a variety of observational datasets, including local weather station data, gridded meteorological data, and high-resolution satellite-based precipitation products. Future climate simulations were analyzed for both mean shifts in climate and changes in climate variability, including extreme events (droughts, heat waves, floods). To explore the impacts of changing climate on maize, bean, and rice yields in Central America, RCM output was used to force the Decision Support System for Agrotechnology Transfer Model (DSSAT). These results were synthesized to create climate change impacts predictions for Central American agriculture that explicitly account for evolving distributions of precipitation and temperature extremes.

  19. Climate Change Impacts on the Mediterranean Coastal Zones

    International Nuclear Information System (INIS)

    The main objective of this paper is to highlight the potential impacts of changes in climatic conditions and in related variables, which could affect coastal areas, as well as to identify potential response measures which could reduce the vulnerability of coastal systems and enhance their adaptability. Attention will be focused on the Mediterranean basin which is in the climate change context, a zone of great interest and of recent concern at the world scale by some features: strong ocean-atmosphere-land interactions; contrast between the small size of the sea and its significant role in the global climate system; possibility to use it at a scaled down model for the monitoring of environmental and climate evolution; critical environmental conditions of some areas and high human pressure; and strong geographical, socio-economic and climatic contrasts. The first section provides an introduction to the climate change issue, the past trends and the projections of future climate at the global scale. The second section presents the main features of the Mediterranean basin and some relevant regional projections of future climatic variables. The third section focuses on the main likely impacts on the Mediterranean coasts. Different coastal systems - such as islands, deltas, estuaries, coastal wetlands and coastal cities - and different climate change impacts - such as inundation, increased flooding, salinisation, salt water intrusion, desertification, and increased erosion - are addressed in this section. Finally the last section brings some conclusions and identify some strategies of adaptations and directions for future research aimed at improving our ability to predict and assess the local impacts of climate change in the region

  20. Disease in a more variable and unpredictable climate

    Science.gov (United States)

    McMahon, T. A.; Raffel, T.; Rohr, J. R.; Halstead, N.; Venesky, M.; Romansic, J.

    2014-12-01

    Global climate change is shifting the dynamics of infectious diseases of humans and wildlife with potential adverse consequences for disease control. Despite this, the role of global climate change in the decline of biodiversity and the emergence of infectious diseases remains controversial. Climate change is expected to increase climate variability in addition to increasing mean temperatures, making climate less predictable. However, few empirical or theoretical studies have considered the effects of climate variability or predictability on disease, despite it being likely that hosts and parasites will have differential responses to climatic shifts. Here we present a theoretical framework for how temperature variation and its predictability influence disease risk by affecting host and parasite acclimation responses. Laboratory experiments and field data on disease-associated frog declines in Latin America support this framework and provide evidence that unpredictable temperature fluctuations, on both monthly and diurnal timescales, decrease frog resistance to the pathogenic chytrid fungus Batrachochytrium dendrobatidis (Bd). Furthermore, the pattern of temperature-dependent growth of the fungus on frogs was inconsistent with the pattern of Bd growth in culture, emphasizing the importance of accounting for the host-parasite interaction when predicting climate-dependent disease dynamics. Consistent with our laboratory experiments, increased regional temperature variability associated with global El Niño climatic events was the best predictor of widespread amphibian losses in the genus Atelopus. Thus, incorporating the effects of small-scale temporal variability in climate can greatly improve our ability to predict the effects of climate change on disease.

  1. A novel bias correction methodology for climate impact simulations

    Directory of Open Access Journals (Sweden)

    S. Sippel

    2015-10-01

    Full Text Available Understanding, quantifying and attributing the impacts of extreme weather and climate events in the terrestrial biosphere is crucial for societal adaptation in a changing climate. However, climate model simulations generated for this purpose typically exhibit biases in their output that hinders any straightforward assessment of impacts. To overcome this issue, various bias correction strategies are routinely used to alleviate climate model deficiencies most of which have been criticized for physical inconsistency and the non-preservation of the multivariate correlation structure. In this study, we introduce a novel, resampling-based bias correction scheme that fully preserves the physical consistency and multivariate correlation structure of the model output. This procedure strongly improves the representation of climatic extremes and variability in a large regional climate model ensemble (HadRM3P, climateprediction.net/weatherathome, which is illustrated for summer extremes in temperature and rainfall over Central Europe. Moreover, we simulate biosphere–atmosphere fluxes of carbon and water using a terrestrial ecosystem model (LPJmL driven by the bias corrected climate forcing. The resampling-based bias correction yields strongly improved statistical distributions of carbon and water fluxes, including the extremes. Our results thus highlight the importance to carefully consider statistical moments beyond the mean for climate impact simulations. In conclusion, the present study introduces an approach to alleviate climate model biases in a physically consistent way and demonstrates that this yields strongly improved simulations of climate extremes and associated impacts in the terrestrial biosphere. A wider uptake of our methodology by the climate and impact modelling community therefore seems desirable for accurately quantifying past, current and future extremes.

  2. Mediterranean climate modelling: variability and climate change scenarios; Modelisation climatique du Bassin mediterraneen: variabilite et scenarios de changement climatique

    Energy Technology Data Exchange (ETDEWEB)

    Somot, S

    2005-12-15

    Air-sea fluxes, open-sea deep convection and cyclo-genesis are studied in the Mediterranean with the development of a regional coupled model (AORCM). It accurately simulates these processes and their climate variabilities are quantified and studied. The regional coupling shows a significant impact on the number of winter intense cyclo-genesis as well as on associated air-sea fluxes and precipitation. A lower inter-annual variability than in non-coupled models is simulated for fluxes and deep convection. The feedbacks driving this variability are understood. The climate change response is then analysed for the 21. century with the non-coupled models: cyclo-genesis decreases, associated precipitation increases in spring and autumn and decreases in summer. Moreover, a warming and salting of the Mediterranean as well as a strong weakening of its thermohaline circulation occur. This study also concludes with the necessity of using AORCMs to assess climate change impacts on the Mediterranean. (author)

  3. Environmental impact of climate change in pakistan

    International Nuclear Information System (INIS)

    Climate change results in the increase or decrease in temperature and rainfall. These have significant impact on environment - impinge agricultural crop yields, affect human health, cause changes to forests and other ecosystems, and even impact our energy supply. Climate change is a global phenomenon and its impact can be observed on Pakistan's economy and environment. This paper contains details concerning the climate change and environmental impacts. It takes into account current and projected key vulnerabilities, prospects for adaptation, and the relationships between climate change mitigation and environment. The purpose of the study is to devise national policies and incentive systems combined with national level capacity-building programs to encourage demand-oriented conservation technologies. Recommendations are also made to abate the climate change related issues in country. (author)

  4. Adaptation to Climate Change and Climate Variability: Do It Now or Wait and See?

    OpenAIRE

    Narita, Daiju; Quaas, Martin F.

    2012-01-01

    As growing attention is paid to climate change adaptation as an actual policy issue, the significant meaning of climate variability in adaptation decisions is beginning to be recognized. By using a real option framework for adaptation in agricultural production, we shed light on how climate change and climate variability affect individuals' (farmers') investment decisions with regard to adaptation (switching from rainfed to irrigated farming). The option value delays adaptation easily for sev...

  5. Impacts, risks, and governance of climate engineering

    Directory of Open Access Journals (Sweden)

    Zhe Liu

    2015-09-01

    Full Text Available Climate engineering is a potential alternative method to curb global warming, and this discipline has garnered considerable attention from the international scientific community including the Chinese scientists. This manuscript provides an overview of several aspects of climate engineering, including its definition, its potential impacts and risk, and its governance status. The overall conclusion is that China is not yet ready to implement climate engineering. However, it is important for China to continue conducting research on climate engineering, particularly with respect to its feasible application within China, its potential social, economic, and environmental impacts, and possible international governance structures and governing principles, with regard to both experimentation and implementation.

  6. Impacts, risks, and governance of climate engineering

    Institute of Scientific and Technical Information of China (English)

    LIU Zhe; CHEN Ying

    2015-01-01

    Climate engineering is a potential alternative method to curb global warming, and this discipline has garnered considerable attention from the international scientific community including the Chinese scientists. This manuscript provides an overview of several aspects of climate engi-neering, including its definition, its potential impacts and risk, and its governance status. The overall conclusion is that China is not yet ready to implement climate engineering. However, it is important for China to continue conducting research on climate engineering, particularly with respect to its feasible application within China, its potential social, economic, and environmental impacts, and possible international governance structures and governing principles, with regard to both experimentation and implementation.

  7. Distributional Aspects of Climate Change Impacts

    International Nuclear Information System (INIS)

    This paper gives a brief review about the state of knowledge on the distributional aspects of climate change impacts. The paper is largely limited to the distribution of impacts between countries (in Section 2). Although there are virtually no estimates reported in the literature, the distribution of impacts within countries is also important. Impact estimates for different sectors (agriculture, health, sea level rise) provides little guidance for estimating differential impacts within countries. It is even harder to find estimates based on social classes. The paper restricts itself to equity about the consequences of climate change. Equity issues about the consequences of emission reduction are ignored here, but should of course be part of a policy analysis. Equity issues about procedures for decision making are also ignored. The paper is organised as follows. Section 2 reviews recent estimates of the regional impacts of climate change. Section 3 discusses alternative ways of aggregating regional impact estimates. Section 4 focusses on the vulnerability of the poor to climate change impacts, both with respect to exposure as well as to their limited capacity for adaptation. Section 5 discusses the impacts of economic development and other dynamic changes on vulnerability. The paper abstains from a discussion of aggregating climate change impacts over time, partly because the literature on that is too substantial to be reviewed here, and partly because, under virtually all scenarios, the current generation is the poorest and therefore particularly worthy in equity considerations. In Section 6 we present salient conclusions

  8. Spatial distribution analysis on climatic variables in northeast China

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    Information ecology is a new research area of modern ecology.Here describes spatial distribution analysis methods of four sorts of climatic variables, i.e. temperature, precipitation, relative humidity and sunshine fraction on Northeast China. First,Digital terrain models was built with large-scale maps and vector data. Then trend surface analysis and interpolation method were used to analyze the spatial distribution of these four kinds of climatic variables at three temporal scale: (1) monthly data; (2)mean monthly data of thirty years, and (3) mean annual data of thirty years. Ecological information system were used for graphics analysis on the spatial distribution of these climate variables.

  9. Climatic variability and cooperation in rangeland management: a case study from Niger

    OpenAIRE

    McCarthy, Nancy; Vanderlinden, Jean-Paul

    2002-01-01

    In this paper, we develop an empirical model of an agro-pastoral system subject to high climatic risk to test the impact of rainfall variability on livestock densities, land allocation patterns and herd mobility observed at the community level. Also, because grazing land is a common-pool resource, we determine the impact of cooperation on these decision variables. To capture different abilities of communities to manage these externalities, we construct indices comprised of factors considered ...

  10. The Role of Low-Level Jets in Regional Climate Variability and Change

    Science.gov (United States)

    Weaver, S. J.

    2015-12-01

    Low Level Jets are ubiquitous features of the global climate system. These "rivers of air" in the lower atmosphere act as a scale transfer mechanism, bridging the larger scale climate variability and change to regionally focused impacts. During the boreal spring and summer, the North American low-level jet (NALLJ) transports copious amounts of momentum, heat, and moisture into central and eastern United States, with significant impacts on regional hydroclimate variability (drought and pluvial), extreme events (tornadic activity), ecology (jellyfish and bird migration), atmospheric constituent transport (ozone), and energy development (wind power). Given the interdisciplinary importance of the NALLJ, its mean state and variability on seasonal to multidecadal timescales will be discussed in a simple framework to stimulate cross-disciplinary thought and discussion with regard to warm season regional climate variability and change.

  11. The ocean's role in climate variability

    Institute of Scientific and Technical Information of China (English)

    CHEN Dake

    2008-01-01

    Because of its vast volume and heat capacity, the ocean contains most of the memory of the earth's ocean - atmosphere coupled system. It has been suggested that the ocean may delay global warming by absorbing large amounts of heat, that it may cause ab- rupt climate change due to its disrupted thermohaline circulation, and that it may set the time-scales for various climate oscilla- tions. Although the slow pace and persistence of oceanic variations give hope to long-range prediction, there still exist large uncer- tainties in climate predictability. Presently available observations and models are generally inadequate for studying and predicting long-term climate changes. However, some short-term fluctuations such as ENSO have been well studied and shown to be highly predictable even with simplified models.

  12. The Dynamics of Ocean Climate Variability.

    Science.gov (United States)

    White, Warren B.; Haney, Robert L.

    1978-01-01

    Halfway through a five-year experimental program designed to test classical concepts of ocean/atmosphere climate dynamics, researchers are finding that the theories may conflict with new data on disturbances in the ocean thermal structure. (Author BB)

  13. Climate change impact on wetland forest plants of SNR Zasavica

    Directory of Open Access Journals (Sweden)

    Čavlović Dragana

    2012-01-01

    Full Text Available Wetlands are among the most vulnerable habitats on the planet. Very complex forest ecosystems are also parts of wetlands. Research and analysis of forest vegetation elements, leads to a conclusion about ecological conditions of wetlands. The aim of the paper is detail forest vegetation study, and analyzing the impact of climate changes on wetland forest vegetations of the strict protection area at the SNR Zasavica Ramsar site. Field research was carried out by using Braun-Blanquet’s Zurich-Montpelier school method. Phytogeographical elements and life forms of plants were determined subsequently, in order to get indicator values of wetland plants. Coupled Regional Climate Model (CRCM, EBU-POM was used for the climate simulations. Exact climatic variables for the site were determined by downscaling method. Climatic variables reference values were taken for the period of 1961-1990, and climate change simulations for the period 2071-2100 (A1B and A2. Indicator values of forest plants taken into consideration were humidity and temperature; therefore, ecological optimums were determined in scales of humidity and temperature. Regional Climate Model shows that there will be a long and intensive dry period in the future, with high temperatures from April till October. Continental winter will be more humid, with higher precipitation, especially in February. Based on the analysis of results it was concluded that wetlands are transitional habitats, also very variable and therefore vulnerable to changes. The changes may lead to the extinction of some plant species.

  14. The Poverty Impacts of Climate Change

    OpenAIRE

    Skoufias, Emmanuel; Rabassa, Mariano; Olivieri, Sergio; Brahmbhatt, Milan

    2011-01-01

    Over the last century, the world has seen a sustained decline in the proportion of people living in poverty. However, there is an increasing concern that climate change could slow or possibly even reverse poverty reduction progress. Given the complexities involved in analyzing climate change impacts on poverty, different approaches can be helpful; this note surveys the results of recent re...

  15. Analysis of inter-variable relations in regional climate model output

    Science.gov (United States)

    Wilcke, Renate; Chandler, Richard

    2015-04-01

    The topic of physical consistency and inter-variable relations of climate model output, in particular when applying statistical downscaling and bias correction to single variables, is widely discussed in the climate impact modelling and climate impact communities. Many situations require the consideration of several climate variables simultaneously, as a result of which it is also necessary to check that the inter-variable dependence structure is simulated realistically by the RCMs. Given that it is common practice to bias-adjust RCM outputs so as to improve their properties with respect to the distribution of variables taken individually, it is also of interest to determine whether inter-variable relationships are affected by empirical bias adjustment procedures such as quantile mapping, that are applied separately to each variable. A pragmatic reason to look at this is, if bias-adjusted outputs are to be used in impacts studies, it is necessary to check that the inter-variable relationships are realistic. A more fundamental reason is, that RCMs are physically based and, before bias correction, their outputs should therefore ideally be physically consistent. However, an empirical bias adjustment procedure has the potential to break the physical consistency, thereby removing one of the strongest justifications for using RCMs in the first place. Based on these considerations, the study aims to answer two questions. The first is to assess the inter-variable relationships in a suite of RCM outputs in more detail than has previously been attempted, by examining conditional probability densities instead of correlations. The second is to quantify the extent to which these conditional densities are distorted by an empirical bias adjustment procedure. The results can be used both to evaluate the ability of current RCMs (bias-adjusted or not) to provide useful information for climate change impact assessments; and also to determine the viability of quantile mapping as a

  16. Distributional aspects of climate change impacts

    Energy Technology Data Exchange (ETDEWEB)

    Tol, R.S.J. [Hamburg University (Germany). Centre for Marine and Climate Research; Vrije Universiteit, Amsterdam (Netherlands). Institute for Environmental Studies; Carnegie Mellon University, Pittsburgh, PA (United States). Center for Integrated Study of the Human Dimensions of Global Change; Downing, T.E. [Stockholm Environment Institute, Oxford (United Kingdom); Kuik, O.J. [Vrije Universiteit, Amsterdam (Netherlands). Institute for Environmental Studies; Smith, J.B. [Stratus Consulting Inc., Boulder, CO (United States)

    2004-10-01

    Climate change is likely to impact more severely on the poorer people of the world, because they are more exposed to the weather, because they are closer to the biophysical and experience limits of climate, and because their adaptive capacity is lower. Estimates of aggregated impacts necessarily make assumptions on the relative importance of sectors, countries and periods; we propose to make these assumption explicit. We introduce a Gini coefficient for climate change impacts, which shows the distribution of impacts is very skewed in the near future and will deteriorate for more than a century before becoming more egalitarian. Vulnerability to climate change depends on more than per capita income alone, so that the geographical pattern of vulnerability is complex, and the relationship between vulnerability and development non-linear and non-monotonous. (author)

  17. Selecting downscaled climate projections for water resource impacts and adaptation

    Science.gov (United States)

    Vidal, Jean-Philippe; Hingray, Benoît

    2015-04-01

    Increasingly large ensembles of global and regional climate projections are being produced and delivered to the climate impact community. However, such an enormous amount of information can hardly been dealt with by some impact models due to computational constraints. Strategies for transparently selecting climate projections are therefore urgently needed for informing small-scale impact and adaptation studies and preventing potential pitfalls in interpreting ensemble results from impact models. This work proposes results from a selection approach implemented for an integrated water resource impact and adaptation study in the Durance river basin (Southern French Alps). A large ensemble of 3000 daily transient gridded climate projections was made available for this study. It was built from different runs of 4 ENSEMBLES Stream2 GCMs, statistically downscaled by 3 probabilistic methods based on the K-nearest neighbours resampling approach (Lafaysse et al., 2014). The selection approach considered here exemplifies one of the multiple possible approaches described in a framework for identifying tailored subsets of climate projections for impact and adaptation studies proposed by Vidal & Hingray (2014). It was chosen based on the specificities of both the study objectives and the characteristics of the projection dataset. This selection approach aims at propagating as far as possible the relative contributions of the four different sources of uncertainties considered, namely GCM structure, large-scale natural variability, structure of the downscaling method, and catchment-scale natural variability. Moreover, it took the form of a hierarchical structure to deal with the specific constraints of several types of impact models (hydrological models, irrigation demand models and reservoir management models). The implemented 3-layer selection approach is therefore mainly based on conditioned Latin Hypercube sampling (Christierson et al., 2012). The choice of conditioning

  18. Social and economic impacts of climate.

    Science.gov (United States)

    Carleton, Tamma A; Hsiang, Solomon M

    2016-09-01

    For centuries, thinkers have considered whether and how climatic conditions-such as temperature, rainfall, and violent storms-influence the nature of societies and the performance of economies. A multidisciplinary renaissance of quantitative empirical research is illuminating important linkages in the coupled climate-human system. We highlight key methodological innovations and results describing effects of climate on health, economics, conflict, migration, and demographics. Because of persistent "adaptation gaps," current climate conditions continue to play a substantial role in shaping modern society, and future climate changes will likely have additional impact. For example, we compute that temperature depresses current U.S. maize yields by ~48%, warming since 1980 elevated conflict risk in Africa by ~11%, and future warming may slow global economic growth rates by ~0.28 percentage points per year. In general, we estimate that the economic and social burden of current climates tends to be comparable in magnitude to the additional projected impact caused by future anthropogenic climate changes. Overall, findings from this literature point to climate as an important influence on the historical evolution of the global economy, they should inform how we respond to modern climatic conditions, and they can guide how we predict the consequences of future climate changes. PMID:27609899

  19. Fisheries: climate change impacts and adaptation

    International Nuclear Information System (INIS)

    The report entitled Climate Change Impacts and Adaptation : A Canadian Perspective, presents a summary of research regarding the impacts of climate change on key sectors over the past five years as it relates to Canada. This chapter on fisheries focuses on the impact of climate change on Canada's marine and freshwater fisheries, and the role of adaptation in reducing the vulnerability of the sector. Canadian fisheries encompass the Atlantic, Pacific and Arctic oceans as well as freshwater systems. Fish health, productivity and distribution is strongly influenced by climatic factors such as air and water temperature, precipitation and wind. Most fish species have a distinct set of environmental conditions for optimal growth and survival. If the conditions change in response to changing climate, the fish may be affected. Some of the impacts include reduced growth, increased competition, a shift in species distribution, greater susceptibility to disease, and altered ecosystem function. Studies show that in some areas, fisheries may already be experiencing the effect of climate change. Recommendations were suggested on how to deal with the impacts associated with climate change in sensitive environments. It was noted that actions taken in the fisheries sector will have implications for the water resources, transportation, tourism and human health sectors. 103 refs., 2 tabs., 6 figs

  20. Glacier response to North Atlantic climate variability during the Holocene

    Directory of Open Access Journals (Sweden)

    N. L. Balascio

    2015-05-01

    Full Text Available Small glaciers and ice caps respond rapidly to climate variations and records of their past extent provide information on the natural envelope of past climate variability. Millennial-scale trends in Holocene glacier size are well documented and correspond with changes in Northern Hemisphere summer insolation. However, there is only sparse and fragmentary evidence for higher frequency variations in glacier size because in many Northern Hemisphere regions glacier advances of the past few hundred years were the most extensive and destroyed the geomorphic evidence of ice growth and retreat during the past several thousand years. Thus, most glacier records have been of limited use for investigating centennial scale climate forcing and feedback mechanisms. Here we report a continuous record of glacier activity for the last 9.5 ka from southeast Greenland, derived from high-resolution measurements on a proglacial lake sediment sequence. Physical and geochemical parameters show that the glaciers responded to previously documented Northern Hemisphere climatic excursions, including the "8.2 ka" cooling event, the Holocene Thermal Maximum, Neoglacial cooling, and 20th Century warming. In addition, the sediments indicate centennial-scale oscillations in glacier size during the late Holocene. Beginning at 4.1 ka, a series of abrupt glacier advances occurred, each lasting ~100 years and followed by a period of retreat, that were superimposed on a gradual trend toward larger glacier size. Thus, while declining summer insolation caused long-term cooling and glacier expansions during the late Holocene, climate system dynamics resulted in repeated episodes of glacier expansion and retreat on multi-decadal to centennial timescales. These episodes coincided with ice rafting events in the North Atlantic Ocean and periods of regional ice cap expansion, which confirms their regional significance and indicates that considerable glacier activity on these timescales is a

  1. Effect of Flux Adjustments on Temperature Variability in Climate Models

    International Nuclear Information System (INIS)

    It has been suggested that ''flux adjustments'' in climate models suppress simulated temperature variability. If true, this might invalidate the conclusion that at least some of observed temperature increases since 1860 are anthropogenic, since this conclusion is based in part on estimates of natural temperature variability derived from flux-adjusted models. We assess variability of surface air temperatures in 17 simulations of internal temperature variability submitted to the Coupled Model Intercomparison Project. By comparing variability in flux-adjusted vs. non-flux adjusted simulations, we find no evidence that flux adjustments suppress temperature variability in climate models; other, largely unknown, factors are much more important in determining simulated temperature variability. Therefore the conclusion that at least some of observed temperature increases are anthropogenic cannot be questioned on the grounds that it is based in part on results of flux-adjusted models. Also, reducing or eliminating flux adjustments would probably do little to improve simulations of temperature variability

  2. Climate Change Impacts on Migration in the Vulnerable Countries

    Science.gov (United States)

    An, Nazan; Incealtin, Gamze; Kurnaz, M. Levent; Şengün Ucal, Meltem

    2014-05-01

    This work focuses on the economic, demographic and environmental drivers of migration related with the sustainable development in underdeveloped and developed countries, which are the most vulnerable to the climate change impacts through the Climate-Development Modeling including climate modeling and panel logit data analysis. We have studied some countries namely Bangladesh, Netherlands, Morocco, Malaysia, Ethiopia and Bolivia. We have analyzed these countries according to their economic, demographic and environmental indicators related with the determinants of migration, and we tried to indicate that their conditions differ according to all these factors concerning with the climate change impacts. This modeling covers some explanatory variables, which have the relationship with the migration, including GDP per capita, population, temperature and precipitation, which indicate the seasonal differences according to the years, the occurrence of natural hazards over the years, coastal location of countries, permanent cropland areas and fish capture which represents the amount of capturing over the years. We analyzed that whether there is a relationship between the migration and these explanatory variables. In order to achieve sustainable development by preventing or decreasing environmental migration due to climate change impacts or related other factors, these countries need to maintain economic, social, political, demographic, and in particular environmental performance. There are some significant risks stemming from climate change, which is not under control. When the economic and environmental conditions are considered, we have to regard climate change to be the more destructive force for those who are less defensible against all of these risks and impacts of uncontrolled climate change. This work was supported by the BU Research Fund under the project number 6990. One of the authors (MLK) was partially supported by Mercator-IPC Fellowship Program.

  3. Welfare impacts of climate change

    NARCIS (Netherlands)

    Hof, Andries F.

    2015-01-01

    Climate change can affect well-being in poor economies more than previously shown if its effect on economic growth, and not only on current production, is considered. But this result does not necessarily suggest greater mitigation efforts are required.

  4. ADAPTATION TO VARIABILITY AND CLIMATE CHANGE: INTERSECTIONS WITH RISK MANAGEMENET

    OpenAIRE

    MAURICIO QUINTERO-ANGEL; PAULINA ALDUNCE; YESID CARVAJAL-ESCOBAR

    2012-01-01

    Given the increase in the frequency of extreme hydro-meteorological events associated with climate variability and/or climate change, and to the increased vulnerability of human societies before those hazards, a higher interest in reducing greenhouse gases by the scientific community appears. This article highlights the importance of adaptation for disaster risk reduction associated with the weather, the climate and their intersections with risk management. It is concluded that adaptation ...

  5. 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 us

  6. Strong increases in flood frequency and discharge of the River Meuse over the late Holocene: impacts of long-term anthropogenic land use change and climate variability

    Directory of Open Access Journals (Sweden)

    P. J. Ward

    2007-08-01

    Full Text Available In recent years the frequency of high-flow events on the Meuse (northwest Europe has been relatively great, and flooding has become a major research theme. To date, research has focused on observed discharge records of the last century and simulations of the coming century. However, it is difficult to delineate changes caused by human activities (land use change and greenhouse gas emissions and natural fluctuations on these timescales. To address this problem we coupled a climate model (ECBilt-CLIO-VECODE and a hydrological model (STREAM to simulate daily Meuse discharge in two time-slices: 4000–3000 BP (natural situation, and 1000–2000 AD (includes anthropogenic influence. For 4000–3000 BP the basin is assumed to be almost fully forested; for 1000–2000 AD we reconstructed land use based on historical sources. For 1000–2000 AD the simulated mean annual discharge (260.9 m³ s−1 is significantly higher than for 4000–3000 BP (244.8 m³ s−1, and the frequency of large high-flow events (discharge >3000 m³ s−1 is higher (recurrence time decreases from 77 to 65 years. On a millennial timescale almost all of this increase can be ascribed to land use changes (especially deforestation; the effects of climatic change are insignificant. For the 20th Century, the simulated mean discharge (270.0 m³ s−1 is higher than in any other century studied, and is ca. 2.5% higher than in the 19th Century (despite an increase in evapotranspiration. Furthermore, the recurrence time of large high-flow events is almost twice as short as under natural conditions (recurrence time decreases from 77 to 40 years. On this timescale climate change (strong increase in annual and winter precipitation overwhelmed land use change as the dominant forcing mechanism.

  7. Climate change variability and Andean agriculture: The context

    OpenAIRE

    Valdivia, Corinne

    2008-01-01

    A presentation by Valdivia from lessons learned in the SANREM CRSP and past research to frame the two day workshop. First session of the workshop: I. Climate Change Variability and Andean Agriculture: The Context Lessons learned from SANREM CRSP on adapting to climate change. LTRA-4 (Practices and Strategies for Vulnerable Agro-Ecosystems)

  8. Adaptation to Climate Variability and Change. Methodological Issues

    International Nuclear Information System (INIS)

    The Intergovernmental Panel on Climate Change (IPCC) convened a Workshop on Adaptation to Climate Variability and Change in Costa Rica in 1998 that involved more than 200 expects and incorporated views from many research communities. This paper summarizes the recommendations from the Workshop and profiles the contributions to the advancement of methodologies for adaptation science. 25 refs

  9. Cropping frequency and area response to climate variability can exceed yield response

    Science.gov (United States)

    Cohn, Avery S.; Vanwey, Leah K.; Spera, Stephanie A.; Mustard, John F.

    2016-06-01

    The sensitivity of agricultural output to climate change has often been estimated by modelling crop yields under climate change scenarios or with statistical analysis of the impacts of year-to-year climatic variability on crop yields. However, the area of cropland and the number of crops harvested per growing season (cropping frequency) both also affect agricultural output and both also show sensitivity to climate variability and change. We model the change in agricultural output associated with the response of crop yield, crop frequency and crop area to year-to-year climate variability in Mato Grosso (MT), Brazil, a key agricultural region. Roughly 70% of the change in agricultural output caused by climate was determined by changes in frequency and/or changes in area. Hot and wet conditions were associated with the largest losses and cool and dry conditions with the largest gains. All frequency and area effects had the same sign as total effects, but this was not always the case for yield effects. A focus on yields alone may therefore bias assessments of the vulnerability of agriculture to climate change. Efforts to reduce climate impacts to agriculture should seek to limit production losses not only from crop yield, but also from changes in cropland area and cropping frequency.

  10. Evaluating historical simulations of CMIP5 GCMs for key climatic variables in Zhejiang Province, China

    Science.gov (United States)

    Xuan, Weidong; Ma, Chong; Kang, Lili; Gu, Haiting; Pan, Suli; Xu, Yue-Ping

    2015-12-01

    Assessing the regional impact of climate change on agriculture, hydrology, and forests is vital for sustainable management. Trustworthy projections of climate change are needed to support these assessments. In this paper, 18 global climate models (GCMs) from the fifth phase of the Coupled Model Intercomparison Project (CMIP5) are evaluated for their ability to simulate regional climate change in Zhejiang Province, Southeast China. Simple graphical approaches and three indices are used to evaluate the performance of six key climatic variables during simulations from 1971 to 2000. These variables include maximum and minimum air temperature, precipitation, wind speed, solar radiation, and relative humidity. These variables are of great importance to researchers and decision makers in climate change impact studies and developing adaptation strategies. This study found that most GCMs failed to reproduce the observed spatial patterns, due to insufficient resolution. However, the seasonal variations of the six variables are simulated well by most GCMs. Maximum and minimum air temperatures are simulated well on monthly, seasonal, and yearly scales. Solar radiation is reasonably simulated on monthly, seasonal, and yearly scales. Compared to air temperature and solar radiation, it was found that precipitation, wind speed, and relative humidity can only be simulated well at seasonal and yearly scales. Wind speed was the variable with the poorest simulation results across all GCMs.

  11. Contrasting climate variability and meteorological drought with perceived drought and climate change in northern Ethiopia

    OpenAIRE

    Meze-Hausken, Elisabeth

    2004-01-01

    The rationale of this paper is to investigate peoples’ perception of climate variability, climate change and drought frequency and compare it with measurements of rainfall variability and anomalies in northern Ethiopia. Statistical analysis of rainfall chronologies was performed and contrasted with qualitative data collected through a survey and questionnaires. Fieldwork studies showed that local authorities, farmers and pastoralists perceived regional climate to have changed d...

  12. Utilizing Satellite Precipitation Products to Understand the Link Between Climate Variability and Malaria

    Science.gov (United States)

    Maggioni, V.; Mousam, A.; Delamater, P. L.; Cash, B. A.; Quispe, A.

    2015-12-01

    Malaria is a public health threat to people globally leading to 198 million cases and 584,000 deaths annually. Outbreaks of vector borne diseases such as malaria can be significantly impacted by climate variables such as precipitation. For example, an increase in rainfall has the potential to create pools of water that can serve as breeding locations for mosquitos. Peru is a country that is currently controlling malaria, but has not been able to completely eliminate the disease. Despite the various initiatives in order to control malaria - including regional efforts to improve surveillance, early detection, prompt treatment, and vector management - malaria cases in Peru have risen between 2011 and 2014. The purpose of this study is to test the hypothesis that climate variability plays a fundamental role in malaria occurrence over a 12-year period (2003-2014) in Peru. When analyzing climate variability, it is important to obtain high-quality, high-resolution data for a time series long enough to draw conclusion about how climate variables have been and are changing. Remote sensing is a powerful tool for measuring and monitoring climate variables continuously in time and space. A widely used satellite-based precipitation product, the Tropical Rainfall Measuring Mission (TRMM) Multi-satellite Precipitation Analysis (TMPA), available globally since 1998, was used to obtain 3-hourly data with a spatial resolution of 0.25° x 0.25°. The precipitation data was linked to weekly (2003-2014) malaria cases collected by health centers and available at a district level all over Peru to investigate the relationship between precipitation and the seasonal and annual variations in malaria incidence. Further studies will incorporate additional climate variables such as temperature, humidity, soil moisture, and surface pressure from remote sensing data products and climate models. Ultimately, this research will help us to understand if climate variability impacts malaria incidence

  13. Advances in Research on South Pacific Sea Temperature Anomaly and Its Impact on Climate Variability%南太平洋海温异常及其气候影响的研究进展

    Institute of Scientific and Technical Information of China (English)

    李刚; 李崇银; 谭言科; 白涛

    2013-01-01

      随着海温观测资料的增多和资料同化技术的发展,南太平洋海温资料质量有了显著提高,这使得南太平洋逐渐成为科学家在研究海气相互作用及影响气候变化的因子时所关注的重点区域。文章系统地介绍了国内外对南太平洋海温(表层和次表层海温)异常变化特征的研究,涉及南太平洋海温异常年际和年代际变化的主要模态及特征,南太平洋海温异常与El Niño–Southern Oscillation、南极环状模的关系,以及南太平洋海温异常变化对大气环流和天气气候的影响(包括南太平洋对南美、东亚及中国地区天气气候的影响)等。在回顾已有研究成果的基础上,提出了一些需要深入研究解决的主要问题,以期引起大家对南太平洋海温异常变化研究的关注,促进对南太平洋海温异常及其气候影响的研究和深刻认识。%With an increasing number of ocean observations and the development of data assimilation models, the quality of the sea temperature data for the South Pacific has improved greatly. Therefore, many studies of large-scale extratropical ocean–atmosphere interaction and its impact on climate variability have focused on the South Pacific. This review introduces systematic studies of the characteristics of the variability of the South Pacific sea temperature (surface and subsurface sea temperature) anomaly, including the interannual and interdecadal variation in the leading mode, the characteristics of the South Pacific, and the relationships among the South Pacific sea temperature anomaly, El Niño–Southern Oscillation, and Southern Annular Mode. It also considers the impact of the South Pacific sea temperature anomalies on the atmospheric circulation and the impact of the South Pacific on the weather and climate in South America, eastern Asia, and China. On the basis of a review of former studies, important questions that require further

  14. Modeling key processes causing climate change and variability

    Energy Technology Data Exchange (ETDEWEB)

    Henriksson, S.

    2013-09-01

    Greenhouse gas warming, internal climate variability and aerosol climate effects are studied and the importance to understand these key processes and being able to separate their influence on the climate is discussed. Aerosol-climate model ECHAM5-HAM and the COSMOS millennium model consisting of atmospheric, ocean and carbon cycle and land-use models are applied and results compared to measurements. Topics at focus are climate sensitivity, quasiperiodic variability with a period of 50-80 years and variability at other timescales, climate effects due to aerosols over India and climate effects of northern hemisphere mid- and high-latitude volcanic eruptions. The main findings of this work are (1) pointing out the remaining challenges in reducing climate sensitivity uncertainty from observational evidence, (2) estimates for the amplitude of a 50-80 year quasiperiodic oscillation in global mean temperature ranging from 0.03 K to 0.17 K and for its phase progression as well as the synchronising effect of external forcing, (3) identifying a power law shape S(f) {proportional_to} f-{alpha} for the spectrum of global mean temperature with {alpha} {approx} 0.8 between multidecadal and El Nino timescales with a smaller exponent in modelled climate without external forcing, (4) separating aerosol properties and climate effects in India by season and location (5) the more efficient dispersion of secondary sulfate aerosols than primary carbonaceous aerosols in the simulations, (6) an increase in monsoon rainfall in northern India due to aerosol light absorption and a probably larger decrease due to aerosol dimming effects and (7) an estimate of mean maximum cooling of 0.19 K due to larger northern hemisphere mid- and high-latitude volcanic eruptions. The results could be applied or useful in better isolating the human-caused climate change signal, in studying the processes further and in more detail, in decadal climate prediction, in model evaluation and in emission policy

  15. Assessing risks of climate variability and climate change for Indonesian rice agriculture.

    Science.gov (United States)

    Naylor, Rosamond L; Battisti, David S; Vimont, Daniel J; Falcon, Walter P; Burke, Marshall B

    2007-05-01

    El Niño events typically lead to delayed rainfall and decreased rice planting in Indonesia's main rice-growing regions, thus prolonging the hungry season and increasing the risk of annual rice deficits. Here we use a risk assessment framework to examine the potential impact of El Niño events and natural variability on rice agriculture in 2050 under conditions of climate change, with a focus on two main rice-producing areas: Java and Bali. We select a 30-day delay in monsoon onset as a threshold beyond which significant impact on the country's rice economy is likely to occur. To project the future probability of monsoon delay and changes in the annual cycle of rainfall, we use output from the Intergovernmental Panel on Climate Change AR4 suite of climate models, forced by increasing greenhouse gases, and scale it to the regional level by using empirical downscaling models. Our results reveal a marked increase in the probability of a 30-day delay in monsoon onset in 2050, as a result of changes in the mean climate, from 9-18% today (depending on the region) to 30-40% at the upper tail of the distribution. Predictions of the annual cycle of precipitation suggest an increase in precipitation later in the crop year (April-June) of approximately 10% but a substantial decrease (up to 75% at the tail) in precipitation later in the dry season (July-September). These results indicate a need for adaptation strategies in Indonesian rice agriculture, including increased investments in water storage, drought-tolerant crops, crop diversification, and early warning systems. PMID:17483453

  16. Free event: Impacts of climate change research

    OpenAIRE

    Blog Admin, Impact of Social Sciences,

    2012-01-01

    Impacts of Climate Change Research, a free, half-day conference hosted by the LSE’s Public Policy Group/Impact of Social Sciences project and Imperial College London, will be held on Monday, 21st May, at the London School of Economics and Political Science.

  17. Representation of spatial and temporal variability of daily wind speed and of intense wind events over the Mediterranean Sea using dynamical downscaling: impact of the regional climate model configuration

    Directory of Open Access Journals (Sweden)

    M. Herrmann

    2011-07-01

    Full Text Available Atmospheric datasets coming from long term reanalyzes of low spatial resolution are used for different purposes. Wind over the sea is, for example, a major ingredient of oceanic simulations. However, the shortcomings of those datasets prevent them from being used without an adequate corrective preliminary treatment. Using a regional climate model (RCM to perform a dynamical downscaling of those large scale reanalyzes is one of the methods used in order to produce fields that realistically reproduce atmospheric chronology and where those shortcomings are corrected. Here we assess the influence of the configuration of the RCM used in this framework on the representation of wind speed spatial and temporal variability and intense wind events on a daily timescale. Our RCM is ALADIN-Climate, the reanalysis is ERA-40, and the studied area is the Mediterranean Sea.

    First, the dynamical downscaling significantly reduces the underestimation of daily wind speed, in average by 9 % over the whole Mediterranean. This underestimation has been corrected both globally and locally, and for the whole wind speed spectrum. The correction is the strongest for periods and regions of strong winds. The representation of spatial variability has also been significantly improved. On the other hand, the temporal correlation between the downscaled field and the observations decreases all the more that one moves eastwards, i.e. further from the atmospheric flux entry. Nonetheless, it remains ~0.7, the downscaled dataset reproduces therefore satisfactorily the real chronology.

    Second, the influence of the choice of the RCM configuration has an influence one order of magnitude smaller than the improvement induced by the initial downscaling. The use of spectral nudging or of a smaller domain helps to improve the realism of the temporal chronology. Increasing the resolution very locally (both spatially and temporally improves the representation of spatial

  18. Impacts of climate change in the Netherlands

    International Nuclear Information System (INIS)

    The main conclusion of the study on the title subject is that the impacts of climatic change in the Netherlands are still limited. However, the impacts will be stronger in the next decades and will be even problematic at the end of this century. In this book an overview is given of probable changes in the climate for the Netherlands, danger for flooding in specific areas of the Netherlands, changes of the nature, impacts for agriculture, tourism and recreation, and industry and businesses, and risks for public health

  19. Women's role in adapting to climate change and variability

    Science.gov (United States)

    Carvajal-Escobar, Y.; Quintero-Angel, M.; García-Vargas, M.

    2008-04-01

    Given that women are engaged in more climate-related change activities than what is recognized and valued in the community, this article highlights their important role in the adaptation and search for safer communities, which leads them to understand better the causes and consequences of changes in climatic conditions. It is concluded that women have important knowledge and skills for orienting the adaptation processes, a product of their roles in society (productive, reproductive and community); and the importance of gender equity in these processes is recognized. The relationship among climate change, climate variability and the accomplishment of the Millennium Development Goals is considered.

  20. Water management to cope with and adapt to climate variability and change.

    Science.gov (United States)

    Hamdy, A.; Trisorio-Liuzzi, G.

    2009-04-01

    In many parts of the world, variability in climatic conditions is already resulting in major impacts. These impacts are wide ranging and the link to water management problems is obvious and profound. The know-how and the available information undoubtedly indicate that climate change will lead to an intensification of the global hydrological cycle and can have major impacts on regional water resources, affecting both ground and surface water supply for sectorial water uses and, in particular, the irrigation field imposing notable negative effects on food security and poverty alleviation programs in most arid and semi-arid developing countries. At the United Nations Millennium Summit, in September 2000, world leaders adopted the Millennium Development Declaration. From this declaration, the IWRM was recognised as the key concept the water sector should be using for water related development and measures and, hence, for achieving the water related MDG's. However, the potential impacts of climate change and increasing climate variability are not sufficiently addressed in the IWRM plans. Indeed, only a very limited IWRM national plans have been prepared, coping with climate variability and changes. This is mainly due to the lack of operational instruments to deal with climate change and climate variability issues. This is particularly true in developing countries where the financial, human and ecological impacts are potentially greatest and where water resources may be already highly stressed, but the capacity to cope and adapt is weakest. Climate change has now brought realities including mainly rising temperatures and increasing frequency of floods and droughts that present new challenges to be addressed by the IWRM practice. There are already several regional and international initiatives underway that focus on various aspects of water resources management those to be linked with climate changes and vulnerability issues. This is the way where the water resources

  1. Water governance: learning by developing adaptive capacity to incorporate climate variability and change.

    Science.gov (United States)

    Kashyap, A

    2004-01-01

    There is increasing evidence that global climate variability and change is affecting the quality and availability of water supplies. Integrated water resources development, use, and management strategies, represent an effective approach to achieve sustainable development of water resources in a changing environment with competing demands. It is also a key to achieving the Millennium Development Goals. It is critical that integrated water management strategies must incorporate the impacts of climate variability and change to reduce vulnerability of the poor, strengthen sustainable livelihoods and support national sustainable development. UNDP's strategy focuses on developing adaptation in the water governance sector as an entry point within the framework of poverty reduction and national sustainable development. This strategy aims to strengthen the capacity of governments and civil society organizations to have access to early warning systems, ability to assess the impact of climate variability and change on integrated water resources management, and developing adaptation intervention through hands-on learning by undertaking pilot activities. PMID:15195430

  2. Quality Assurance for Essential Climate Variables

    Science.gov (United States)

    Folkert Boersma, K.; Muller, Jan-Peter

    2015-04-01

    Satellite data are of central interest to the QA4ECV project. Satellites have revolutionized the Earth's observation system of climate change and air quality over the past three decades, providing continuous data for the entire Earth. However, many users of these data are lost in the fog as to the quality of these satellite data. Because of this, the European Union expressed in its 2013 FP7 Space Research Call a need for reliable, traceable, and understandable quality information on satellite data records that could serve as a blueprint contribution to a future Copernicus Climate Change Service. The potential of satellite data to benefit climate change and air quality services is too great to be ignored. QA4ECV therefore bridges the gap between end-users of satellite data and the satellite data products. We are developing an internationally acceptable Quality Assurance (QA) framework that provides understandable and traceable quality information for satellite data used in climate and air quality services. Such a framework should deliver the historically linked long-term data sets that users need, in a format that they can readily use. QA4ECV has approached more than 150 users and suppliers of satellite data to collect their needs and expectations. The project will use their response as a guideline for developing user-friendly tools to obtain information on the completeness, accuracy, and fitness-for-purpose of the satellite datasets. QA4ECV collaborates with 4 joint FP7 Space projects in reaching out to scientists, policy makers, and other end-users of satellite data to improve understanding of the special challenges -and also opportunities- of working with satellite data for climate and air quality purposes. As a demonstration of its capacity, QA4ECV will generate multi-decadal climate data records for 3 atmospheric ECV precursors (nitrogen dioxide, formaldehyde, and carbon monoxide) and 3 land ECVs (albedo, leaf area index and absorbed photosynthetically active

  3. 500 years of regional forest growth variability and links to climatic extreme events in Europe

    OpenAIRE

    Babst, Flurin; Carrer, Marco; Poulter, Benjamin; Urbinati, Carlo; Neuwirth, Burkhard; Frank, David

    2012-01-01

    Climatic extreme events strongly affect forest growth and thus significantly influence the inter-annual terrestrial carbon balance. As we are facing an increase in frequency and intensity of climate extremes, extensive empirical archives are required to assess continental scale impacts of temperature and precipitation anomalies. Here we divide a tree-ring network of approximately 1000 sites into fifteen groups of similar high-frequency growth variability to reconstruct regional positive and n...

  4. Future Warming Patterns Linked to Today’s Climate Variability

    Science.gov (United States)

    Dai, Aiguo

    2016-01-01

    The reliability of model projections of greenhouse gas (GHG)-induced future climate change is often assessed based on models’ ability to simulate the current climate, but there has been little evidence that connects the two. In fact, this practice has been questioned because the GHG-induced future climate change may involve additional physical processes that are not important for the current climate. Here I show that the spatial patterns of the GHG-induced future warming in the 21st century is highly correlated with the patterns of the year-to-year variations of surface air temperature for today’s climate, with areas of larger variations during 1950-1979 having more GHG-induced warming in the 21st century in all climate models. Such a relationship also exists in other climate fields such as atmospheric water vapor, and it is evident in observed temperatures from 1950-2010. The results suggest that many physical processes may work similarly in producing the year-to-year climate variations in the current climate and the GHG-induced long-term changes in the 21st century in models and in the real world. They support the notion that models that simulate present-day climate variability better are likely to make more reliable predictions of future climate change.

  5. Future Warming Patterns Linked to Today's Climate Variability.

    Science.gov (United States)

    Dai, Aiguo

    2016-01-01

    The reliability of model projections of greenhouse gas (GHG)-induced future climate change is often assessed based on models' ability to simulate the current climate, but there has been little evidence that connects the two. In fact, this practice has been questioned because the GHG-induced future climate change may involve additional physical processes that are not important for the current climate. Here I show that the spatial patterns of the GHG-induced future warming in the 21(st) century is highly correlated with the patterns of the year-to-year variations of surface air temperature for today's climate, with areas of larger variations during 1950-1979 having more GHG-induced warming in the 21(st) century in all climate models. Such a relationship also exists in other climate fields such as atmospheric water vapor, and it is evident in observed temperatures from 1950-2010. The results suggest that many physical processes may work similarly in producing the year-to-year climate variations in the current climate and the GHG-induced long-term changes in the 21(st) century in models and in the real world. They support the notion that models that simulate present-day climate variability better are likely to make more reliable predictions of future climate change. PMID:26750759

  6. Impact of land levelling on soil moisture and runoff variability in vineyards under different rainfall distributions in a Mediterranean climate and its influence on crop productivity

    Science.gov (United States)

    Ramos, M. C.; Martínez-Casasnovas, J. A.

    2006-04-01

    This paper deals with the effects of land levelling on soil hydrological properties and spatial variability of soil moisture at different depths in bare vineyard fields under different rainfall distributions over the year. The research was carried out in a levelled vineyard in the Penedès region (NE Spain), which is representative of the land management practices in that area. Twelve locations were instrumented in the selected plot to control soil moisture periodically at different depths (0-20, 20-40, 40-60 cm, using a TDR tube probe), and runoff (using Gerlach collectors located at the same positions) during the period April 2002-March 2004. Rainfalls were recorded at one-minute intervals in the experimental field using a pluviometer linked to a data-logger. The vine yield and its relationship with the rainfall distribution over the year was evaluated in this levelled vineyard vs. a less transformed vineyard. The land levelling works carried out in the plot before the establishment of the vineyard led to major differences in soil depth (ranging from 50 to 110 cm) and in soil layer characteristics along and across the plot. This helps to generate different soil moisture conditions at the same depth at different positions of the plot. The areas located at the top of the plot showed soil moisture conditions in the surface layer that were up to 5% lower than down slope, although with high variability across the plot. Soil moisture in the whole profile depends on the intensity of rainfall more than total rainfall. At high intensities, soil moisture increases only occur in the surface layer, but no significant increases are observed in deeper layers, where vines have most of their roots. On the other hand, under low intensity rainfalls the soil water content increases in the whole profile. Levelled plots showed a yield reduction in comparison with those undergoing less transformation, which was exacerbated by a very irregular rainfall distribution: for a similar total

  7. Different responses of Ross River virus to climate variability between coastline and inland cities in Queensland, Australia

    OpenAIRE

    Tong, S; Hu, W

    2002-01-01

    Aims: To examine the potential impact of climate variability on the transmission of Ross River virus (RRv) infection, and to assess the difference in the potential predictors of RRv incidence in coastline and inland regions, Queensland, Australia.

  8. Climate change impacts: an Ontario perspective

    International Nuclear Information System (INIS)

    Significant changes in the climate system which are likely to affect biophysical, social and economic systems in various ways, were discussed. Trends in greenhouse gas levels show that during the 20. century, human activity has changed the make-up of the atmosphere and its greenhouse effect properties. A pilot study on the impacts of climate change identified changes in the water regime such as declines in net basin supply, lake levels and outflows, as important concerns. These changes would have impacts on water quality, wetlands, municipal water supply, hydroelectric power generation, commercial shipping, tourism and recreation, and to a lesser extent, on food productions. Climate impact assessments suggest that world conditions will change significantly as a result. Those with less resources are likely to be most affected by climate change, and the impacts on other regions of the world will be more significant to Ontario than the direct impacts on Ontario itself. In an effort to keep pace with global changes, Ontario will have to limit emissions, conduct research in innovative technology and develop greater awareness of the risk of climate change. refs., tabs., figs

  9. A Decision Analysis Tool for Climate Impacts, Adaptations, and Vulnerabilities

    Energy Technology Data Exchange (ETDEWEB)

    Omitaomu, Olufemi A [ORNL; Parish, Esther S [ORNL; Nugent, Philip J [ORNL

    2016-01-01

    Climate change related extreme events (such as flooding, storms, and drought) are already impacting millions of people globally at a cost of billions of dollars annually. Hence, there are urgent needs for urban areas to develop adaptation strategies that will alleviate the impacts of these extreme events. However, lack of appropriate decision support tools that match local applications is limiting local planning efforts. In this paper, we present a quantitative analysis and optimization system with customized decision support modules built on geographic information system (GIS) platform to bridge this gap. This platform is called Urban Climate Adaptation Tool (Urban-CAT). For all Urban-CAT models, we divide a city into a grid with tens of thousands of cells; then compute a list of metrics for each cell from the GIS data. These metrics are used as independent variables to predict climate impacts, compute vulnerability score, and evaluate adaptation options. Overall, the Urban-CAT system has three layers: data layer (that contains spatial data, socio-economic and environmental data, and analytic data), middle layer (that handles data processing, model management, and GIS operation), and application layer (that provides climate impacts forecast, adaptation optimization, and site evaluation). The Urban-CAT platform can guide city and county governments in identifying and planning for effective climate change adaptation strategies.

  10. Do bioclimate variables improve performance of climate envelope models?

    Science.gov (United States)

    Watling, James I.; Romañach, Stephanie S.; Bucklin, David N.; Speroterra, Carolina; Brandt, Laura A.; Pearlstine, Leonard G.; Mazzotti, Frank J.

    2012-01-01

    Climate envelope models are widely used to forecast potential effects of climate change on species distributions. A key issue in climate envelope modeling is the selection of predictor variables that most directly influence species. To determine whether model performance and spatial predictions were related to the selection of predictor variables, we compared models using bioclimate variables with models constructed from monthly climate data for twelve terrestrial vertebrate species in the southeastern USA using two different algorithms (random forests or generalized linear models), and two model selection techniques (using uncorrelated predictors or a subset of user-defined biologically relevant predictor variables). There were no differences in performance between models created with bioclimate or monthly variables, but one metric of model performance was significantly greater using the random forest algorithm compared with generalized linear models. Spatial predictions between maps using bioclimate and monthly variables were very consistent using the random forest algorithm with uncorrelated predictors, whereas we observed greater variability in predictions using generalized linear models.

  11. Assessing Climate Change Impacts on Global Hydropower

    OpenAIRE

    Aanund Killingtveit; Byman Hamududu

    2012-01-01

    Currently, hydropower accounts for close to 16% of the world’s total power supply and is the world’s most dominant (86%) source of renewable electrical energy. The key resource for hydropower generation is runoff, which is dependent on precipitation. The future global climate is uncertain and thus poses some risk for the hydropower generation sector. The crucial question and challenge then is what will be the impact of climate change on global hydropower generation and what are the resulting ...

  12. Transport impacts on atmosphere and climate: Metrics

    OpenAIRE

    J. S. Fuglestvedt; K. P. Shine; Berntsen, T.; Cook, J; Lee, D. S.; Stenke, A.; Skeie, R; Velders, G.J.M.; Waitz, I. A.

    2010-01-01

    The transport sector emits a wide variety of gases and aerosols, with distinctly different characteristics which influence climate directly and indirectly via chemical and physical processes. Tools that allow these emissions to be placed on some kind of common scale in terms of their impact on climate have a number of possible uses such as: in agreements and emission trading schemes; when considering potential trade-offs between changes in emissions resulting from technological or operational...

  13. Climate Change Impacts on Czech Agriculture

    Czech Academy of Sciences Publication Activity Database

    Žalud, Z.; Trnka, M.; Hlavinka, P.; Dubrovský, Martin; Svobodová, E.; Semerádová, D.; Bartošová, L.; Balek, J.; Eitzinger, J.; Možný, M.

    Rijeka: InTech, 2011 - (Blanco, J.; Kheradmand, H.), s. 251-278 ISBN 978-953-307-411-5 R&D Projects: GA AV ČR IAA300420806 Institutional research plan: CEZ:AV0Z30420517 Keywords : climate change * agriculture Subject RIV: DG - Athmosphere Sciences, Meteorology http://www.intechopen.com/articles/show/title/ climate - change -impacts-on-czech-agriculture

  14. Climate Change Impacts on Czech Agriculture

    Czech Academy of Sciences Publication Activity Database

    Žalud, Zdeněk; Trnka, Miroslav; Hlavinka, Petr; Dubrovský, Martin; Svobodová, Eva; Semerádová, Daniela; Bartošová, Lenka; Balek, J.; Eitzinger, Josef; Možný, M.

    Rijeka: InTech, 2011 - (Blanco, J.; Kheradmand, H.), s. 251-277 ISBN 978-953-307-411-5 R&D Projects: GA MŠk(CZ) ED1.1.00/02.0073 Institutional research plan: CEZ:AV0Z60870520 Keywords : climate change * agriculture Subject RIV: EH - Ecology, Behaviour http://www.intechopen.com/articles/show/title/ climate - change -impacts-on-czech-agriculture

  15. Taking the pulse of mountains: Ecosystem responses to climatic variability

    Science.gov (United States)

    Fagre, D.B.; Peterson, D.L.; Hessl, A.E.

    2003-01-01

    An integrated program of ecosystem modeling and field studies in the mountains of the Pacific Northwest (U.S.A.) has quantified many of the ecological processes affected by climatic variability. Paleoecological and contemporary ecological data in forest ecosystems provided model parameterization and validation at broad spatial and temporal scales for tree growth, tree regeneration and treeline movement. For subalpine tree species, winter precipitation has a strong negative correlation with growth; this relationship is stronger at higher elevations and west-side sites (which have more precipitation). Temperature affects tree growth at some locations with respect to length of growing season (spring) and severity of drought at drier sites (summer). Furthermore, variable but predictable climate-growth relationships across elevation gradients suggest that tree species respond differently to climate at different locations, making a uniform response of these species to future climatic change unlikely. Multi-decadal variability in climate also affects ecosystem processes. Mountain hemlock growth at high-elevation sites is negatively correlated with winter snow depth and positively correlated with the winter Pacific Decadal Oscillation (PDO) index. At low elevations, the reverse is true. Glacier mass balance and fire severity are also linked to PDO. Rapid establishment of trees in subalpine ecosystems during this century is increasing forest cover and reducing meadow cover at many subalpine locations in the western U.S.A. and precipitation (snow depth) is a critical variable regulating conifer expansion. Lastly, modeling potential future ecosystem conditions suggests that increased climatic variability will result in increasing forest fire size and frequency, and reduced net primary productivity in drier, east-side forest ecosystems. As additional empirical data and modeling output become available, we will improve our ability to predict the effects of climatic change

  16. Estimating Non-Market Impacts of Climate Change and Climate Policy

    International Nuclear Information System (INIS)

    A number of studies over the past few decades have attempted to estimate the potential impacts of climate change and climate policy. For reasons related to, inter alia, our incomplete understanding of the workings of many natural and social systems, the tremendous spatial and temporal variability in these systems, and the long time frames over which the issue of climate change will play out, there are large degrees of uncertainty in these estimates. Some of the most rancorous debates, however, have focused on those studies that have attempted to place economic values on these impacts. This should not be surprising as the outcomes of these studies have played an important role in the debates over climate policy. Rightly or wrongly, the estimates presented in these studies are often held up against similar estimates of the costs of mitigating against climate change. The process of economic valuation of environmental and social issues is still relatively young, much less its application to the potential impacts of climate change and climate policy. Issues such as climate change push existing techniques to their limits, and possibly beyond. Among the topics that have raised the most concern are the choice of the proper baseline against which to make comparisons, the treatment of uncertainty in human and natural systems, incomplete accounting, the actual valuation of specific impacts, and the aggregation of impacts over time and across widely differing societies. Some of the more recent studies have tried to address these issues, albeit not always satisfactorily. One aspect that makes the economic valuation of environmental and social issues difficult is that it requires addressing impacts that are not typically associated with economic markets, so called nonmarket impacts. In addition to not being traded in markets, many of these impacts affect goods and services that have the characteristic of being public goods, i.e. it is not possible to restrict their use to a

  17. Deglacial climate variability in central Florida, USA

    Science.gov (United States)

    Willard, D.A.; Bernhardt, C.E.; Brooks, G.R.; Cronin, T. M.; Edgar, T.; Larson, R.

    2007-01-01

    Pollen and ostracode evidence from lacustrine sediments underlying modern Tampa Bay, Florida, document frequent and abrupt climatic and hydrological events superimposed on deglacial warming in the subtropics. Radiocarbon chronology on well-preserved mollusk shells and pollen residue from core MD02-2579 documents continuous sedimentation in a variety of non-marine habitats in a karst-controlled basin from 20 ka to 11.5 ka. During the last glacial maximum (LGM), much drier and cooler-than-modern conditions are indicated by pollen assemblages enriched in Chenopodiaceae and Carya, with rare Pinus (Pinus pollen increased to 20–40% during the warming of the initial deglaciation (∼ 17.2 ka), reaching near modern abundance (60–80%) during warmer, moister climates of the Bølling/Allerød interval (14.7–12.9 ka). Within the Bølling/Allerød, centennial-scale dry events corresponding to the Older Dryas and Intra-Allerød Cold Period indicate rapid vegetation response (

  18. Quantifying the Uncertainties of Aerosol Indirect Effects and Impacts on Decadal-Scale Climate Variability in NCAR CAM5 and CESM1

    Energy Technology Data Exchange (ETDEWEB)

    Park, Sungsu

    2014-12-12

    The main goal of this project is to systematically quantify the major uncertainties of aerosol indirect effects due to the treatment of moist turbulent processes that drive aerosol activation, cloud macrophysics and microphysics in response to anthropogenic aerosol perturbations using the CAM5/CESM1. To achieve this goal, the P.I. hired a postdoctoral research scientist (Dr. Anna Fitch) who started her work from the Nov.1st.2012. In order to achieve the project goal, the first task that the Postdoc. and the P.I. did was to quantify the role of subgrid vertical velocity variance on the activation and nucleation of cloud liquid droplets and ice crystals and its impact on the aerosol indirect effect in CAM5. First, we analyzed various LES cases (from dry stable to cloud-topped PBL) to check whether this isotropic turbulence assumption used in CAM5 is really valid. It turned out that this isotropic turbulence assumption is not universally valid. Consequently, from the analysis of LES, we derived an empirical formulation relaxing the isotropic turbulence assumption used for the CAM5 aerosol activation and ice nucleation, and implemented the empirical formulation into CAM5/CESM1, and tested in the single-column and global simulation modes, and examined how it changed aerosol indirect effects in the CAM5/CESM1. These results were reported in the poster section in the 18th Annual CESM workshop held in Breckenridge, CO during Jun.17-20.2013. While we derived an empirical formulation from the analysis of couple of LES from the first task, the general applicability of that empirical formulation was questionable, because it was obtained from the limited number of LES simulations. The second task we did was to derive a more fundamental analytical formulation relating vertical velocity variance to TKE using other information starting from basic physical principles. This was a somewhat challenging subject, but if this could be done in a successful way, it could be directly

  19. CLIMATE CHANGE IMPACTS ON WATER RESOURCES

    Directory of Open Access Journals (Sweden)

    T.M. CORNEA

    2011-03-01

    Full Text Available Climate change impacts on water resources – The most recent scientific assessment by the Intergovernmental Panel on Climate Change (IPCC [6] concludes that, since the late 19th century, anthropogenic induced emissions of greenhouse gases have contributed to an increase in global surface temperatures of about 0.3 to 0.6o C. Based on the IPCC’s scenario of future greenhouse gas emissions and aerosols a further increase of 2o C is expected by the year 2100. Plants, animals, natural and managed ecosystems, and human settlements are susceptible to variations in the storage, fluxes, and quality of water and sensitive to climate change. From urban and agricultural water supplies to flood management and aquatic ecosystem protection, global warming is affecting all aspects of water resource management. Rising temperatures, loss of snowpack, escalating size and frequency of flood events, and rising sea levels are just some of the impacts of climate change that have broad implications for the management of water resources. With robust scientific evidence showing that human-induced climate change is occurring, it is critical to understand how water quantity and quality might be affected. The purpose of this paper is to highlight the environmental risks caused by climate anomalies on water resources, to examine the negative impacts of a greenhouse warming on the supply and demand for water and the resulting socio-economic implications.

  20. Planning for Production of Freshwater Fish Fry in a Variable Climate in Northern Thailand

    Science.gov (United States)

    Uppanunchai, Anuwat; Apirumanekul, Chusit; Lebel, Louis

    2015-10-01

    Provision of adequate numbers of quality fish fry is often a key constraint on aquaculture development. The management of climate-related risks in hatchery and nursery management operations has not received much attention, but is likely to be a key element of successful adaptation to climate change in the aquaculture sector. This study explored the sensitivities and vulnerability of freshwater fish fry production in 15 government hatcheries across Northern Thailand to climate variability and evaluated the robustness of the proposed adaptation measures. This study found that hatcheries have to consider several factors when planning production, including: taking into account farmer demand; production capacity of the hatchery; availability of water resources; local climate and other area factors; and, individual species requirements. Nile tilapia is the most commonly cultured species of freshwater fish. Most fry production is done in the wet season, as cold spells and drought conditions disrupt hatchery production and reduce fish farm demand in the dry season. In the wet season, some hatcheries are impacted by floods. Using a set of scenarios to capture major uncertainties and variability in climate, this study suggests a couple of strategies that should help make hatchery operations more climate change resilient, in particular: improving hatchery operations and management to deal better with risks under current climate variability; improving monitoring and information systems so that emerging climate-related risks are known sooner and understood better; and, research and development on alternative species, breeding programs, improving water management and other features of hatchery operations.

  1. Climate Change Impact Assessment of Food- and Waterborne Diseases.

    Science.gov (United States)

    Semenza, Jan C; Herbst, Susanne; Rechenburg, Andrea; Suk, Jonathan E; Höser, Christoph; Schreiber, Christiane; Kistemann, Thomas

    2012-04-01

    The PubMed and ScienceDirect bibliographic databases were searched for the period of 1998-2009 to evaluate the impact of climatic and environmental determinants on food- and waterborne diseases. The authors assessed 1,642 short and concise sentences (key facts), which were extracted from 722 relevant articles and stored in a climate change knowledge base. Key facts pertaining to temperature, precipitation, water, and food for 6 selected pathogens were scrutinized, evaluated, and compiled according to exposure pathways. These key facts (corresponding to approximately 50,000 words) were mapped to 275 terminology terms identified in the literature, which generated 6,341 connections. These relationships were plotted on semantic network maps to examine the interconnections between variables. The risk of campylobacteriosis is associated with mean weekly temperatures, although this link is shown more strongly in the literature relating to salmonellosis. Irregular and severe rain events are associated with Cryptosporidium sp. outbreaks, while noncholera Vibrio sp. displays increased growth rates in coastal waters during hot summers. In contrast, for Norovirus and Listeria sp. the association with climatic variables was relatively weak, but much stronger for food determinants. Electronic data mining to assess the impact of climate change on food- and waterborne diseases assured a methodical appraisal of the field. This climate change knowledge base can support national climate change vulnerability, impact, and adaptation assessments and facilitate the management of future threats from infectious diseases. In the light of diminishing resources for public health this approach can help balance different climate change adaptation options. PMID:24808720

  2. Vegetation response to climate variability in India from 2001 to 2010

    Science.gov (United States)

    Hashimoto, H.; Milesi, C.; Wang, W.; Ganguly, S.; Michaelis, A.; Nemani, R.

    2011-12-01

    Food supply in India is a critical issue in sustaining a large population, and more accurate predictability of agricultural productivity is necessary for policy makers. After the Green revolution, the productivity in India has increased dramatically, but the leveling-off of the productivity was expected in the near future. Decreasing of ground water was already observed and some climate models predict a higher frequency of drought in the 21st century. For a better understanding of vegetation response to climate change, we analyzed the satellite images of India from 2001 to 2010. MODIS satellite imagery shows high spatial variability in vegetation indices in response to climate variability. In this study we scrutinize the cause and mechanism of the spatial variability in vegetation growth in India. First, we tried to find the corresponding climate variability from re-analysis data (MERRA and NCEP-NCAR reanalysis data) and satellite imagery such as TRMM, GIMMS, and MODIS, as well as interpolated climate observation data (CRU). Although the precipitation variability due to ENSO has the strongest impact on vegetation growth, the other climate variability, such as shortwave radiation, also perturbed the vegetation response to climate changes. Second, we proved our hypothesis explaining the vegetation growth trend by running the Terrestrial Observation and Prediction System (TOPS) model. The model results were compared with satellite images and showed reasonable spatial pattern of net primary production to explain the observed vegetation growth variability to climate change. Those results can contribute to a more profound understanding of the mechanism of vegetation growth in India toward future prediction in food supply.

  3. High frequency variability in recent climate and the North Atlantic Oscillation

    Czech Academy of Sciences Publication Activity Database

    Bodri, L.; Čermák, Vladimír

    2003-01-01

    Roč. 74, 1/2 (2003), s. 33-40. ISSN 0177-798X R&D Projects: GA AV ČR IAA3012005 Institutional research plan: CEZ:AV0Z3012916 Keywords : North Atlantic Oscillation * recent climate * temperature variability Subject RIV: DC - Siesmology, Volcanology, Earth Structure Impact factor: 1.147, year: 2003

  4. THE EFFECTS OF CLIMATIC VARIABLES AND CROP AREA ON MAIZE YIELD AND VARIABILITY IN GHANA

    Directory of Open Access Journals (Sweden)

    Henry De-Graft Acquah

    2012-10-01

    Full Text Available Climate change tends to have negative effects on crop yield through its influence on crop production. Understanding the relationship between climatic variables and crop area on the mean and variance of crop yield will facilitate development of appropriate policies to cope with climate change. This paper examines the effects of climatic variables and crop area on the mean and variance of maize yield in Ghana. The Just and Pope stochastic production function using the Cobb-Douglas functional form was employed. The results show that average maize yield is positively related to crop area and negatively related to rainfall and temperature. Furthermore, increase in crop area and temperature will enlarge maize yield variability while rainfall increase will decrease the variability in maize yield.

  5. Projecting the Hydrologic Impacts of Climate Change on Montane Wetlands

    Science.gov (United States)

    Hamlet, Alan F.; Palen, Wendy J.; Lawler, Joshua J.; Halabisky, Meghan

    2015-01-01

    Wetlands are globally important ecosystems that provide critical services for natural communities and human society. Montane wetland ecosystems are expected to be among the most sensitive to changing climate, as their persistence depends on factors directly influenced by climate (e.g. precipitation, snowpack, evaporation). Despite their importance and climate sensitivity, wetlands tend to be understudied due to a lack of tools and data relative to what is available for other ecosystem types. Here, we develop and demonstrate a new method for projecting climate-induced hydrologic changes in montane wetlands. Using observed wetland water levels and soil moisture simulated by the physically based Variable Infiltration Capacity (VIC) hydrologic model, we developed site-specific regression models relating soil moisture to observed wetland water levels to simulate the hydrologic behavior of four types of montane wetlands (ephemeral, intermediate, perennial, permanent wetlands) in the U. S. Pacific Northwest. The hybrid models captured observed wetland dynamics in many cases, though were less robust in others. We then used these models to a) hindcast historical wetland behavior in response to observed climate variability (1916–2010 or later) and classify wetland types, and b) project the impacts of climate change on montane wetlands using global climate model scenarios for the 2040s and 2080s (A1B emissions scenario). These future projections show that climate-induced changes to key driving variables (reduced snowpack, higher evapotranspiration, extended summer drought) will result in earlier and faster drawdown in Pacific Northwest montane wetlands, leading to systematic reductions in water levels, shortened wetland hydroperiods, and increased probability of drying. Intermediate hydroperiod wetlands are projected to experience the greatest changes. For the 2080s scenario, widespread conversion of intermediate wetlands to fast-drying ephemeral wetlands will likely reduce

  6. Projecting the Hydrologic Impacts of Climate Change on Montane Wetlands.

    Science.gov (United States)

    Lee, Se-Yeun; Ryan, Maureen E; Hamlet, Alan F; Palen, Wendy J; Lawler, Joshua J; Halabisky, Meghan

    2015-01-01

    Wetlands are globally important ecosystems that provide critical services for natural communities and human society. Montane wetland ecosystems are expected to be among the most sensitive to changing climate, as their persistence depends on factors directly influenced by climate (e.g. precipitation, snowpack, evaporation). Despite their importance and climate sensitivity, wetlands tend to be understudied due to a lack of tools and data relative to what is available for other ecosystem types. Here, we develop and demonstrate a new method for projecting climate-induced hydrologic changes in montane wetlands. Using observed wetland water levels and soil moisture simulated by the physically based Variable Infiltration Capacity (VIC) hydrologic model, we developed site-specific regression models relating soil moisture to observed wetland water levels to simulate the hydrologic behavior of four types of montane wetlands (ephemeral, intermediate, perennial, permanent wetlands) in the U. S. Pacific Northwest. The hybrid models captured observed wetland dynamics in many cases, though were less robust in others. We then used these models to a) hindcast historical wetland behavior in response to observed climate variability (1916-2010 or later) and classify wetland types, and b) project the impacts of climate change on montane wetlands using global climate model scenarios for the 2040s and 2080s (A1B emissions scenario). These future projections show that climate-induced changes to key driving variables (reduced snowpack, higher evapotranspiration, extended summer drought) will result in earlier and faster drawdown in Pacific Northwest montane wetlands, leading to systematic reductions in water levels, shortened wetland hydroperiods, and increased probability of drying. Intermediate hydroperiod wetlands are projected to experience the greatest changes. For the 2080s scenario, widespread conversion of intermediate wetlands to fast-drying ephemeral wetlands will likely reduce

  7. Regional climate impacts of a possible future grand solar minimum

    OpenAIRE

    Ineson, Sarah; Maycock, Amanda C.; Gray, Lesley J; Scaife, Adam A.; Dunstone, Nick J.; Harder, Jerald W.; Knight, Jeff R.; Lockwood, Mike; Manners, James C; Wood, Richard A.

    2015-01-01

    Any reduction in global mean near-surface temperature due to a future decline in solar activity is likely to be a small fraction of projected anthropogenic warming. However, variability in ultraviolet solar irradiance is linked to modulation of the Arctic and North Atlantic Oscillations, suggesting the potential for larger regional surface climate effects. Here, we explore possible impacts through two experiments designed to bracket uncertainty in ultraviolet irradiance in a scenario in which...

  8. Polar forcing of natural variability of the atmospheric climate

    International Nuclear Information System (INIS)

    A comparative analysis of the latitudinal distribution of the climatic variability of different characteristics of the upper atmospheric state and heat balance constituents from data of climatic archives reveals the features of the variability forcing in the direction of the North Pole. The polar forcing of the variability of thermodynamic atmospheric parameters (temperature, pressure, geopotential) is shown to be formed by the fluctuations of meridional air exchange. Intercorrelated analytical expressions are obtained for root-mean-square deviations of average zonal values of the parameters, indicating the effect of polar forcing in the observed variability. The effect of polar forcing of air temperature variability is simulated and its dependence on albedo changes and the Greenhouse effect is considered by means of the energy-balance zonal atmospheric model

  9. Climate variability according to triple saros gravity cycles

    CERN Document Server

    Livingston, William R

    2013-01-01

    I describe a climate model which corresponds directly to eclipse cycles. The theory is based upon a similarity between the 54 year triple saros eclipse period and the periodicity of drought. I argue that eclipse shadows are an indication of gravity cycles, and that variable lunar gravitation is the most significant aspect of the eclipse process. I reinforce the idea that lunar gravitational forcing has a profound effect on the water vapor in Earth's atmosphere, and can affect the density and location of clouds. I explore the possibility that decadal variability of ocean surface levels may be explained by triple saros gravity cycles. I point out that lunar gravitation was excluded from the most significant climate report of 2007, and that climate data contradictions have been overlooked by researchers. I focus on the value of data that has not been aggregated into global averages. I touch upon the history of global warming, and I offer predictions based upon 54 year climate periodicity.

  10. Climate challenge 2012: growth and climate change - Socio-economical impacts of climate change. Conference proceedings

    International Nuclear Information System (INIS)

    The contributions of this conference session proposed comments and discussion on the relationship between climate change and 'green' growth, on the status of scientific knowledge on climate change (from global to local), on the way to perform carbon print assessment and to decide which actions to implement, on the costs and opportunity of impacts of climate change, on the economy of adaptation, on the benefits and costs of the adaptation policy, and on impacts of climate change on employment in quantitative terms and in terms of profession types

  11. Human activity and climate variability project - annual report 2002

    International Nuclear Information System (INIS)

    Work is well underway on identifying the spatial and temporal extent, direction and range of trace element transport across Tasmania through analysis of lake sediments; A follow up investigation of sedimentation and pollution in the Nattai River catchment following the devastating 2001 bushfires in the region has been completed; The project has been extended to include investigations of evidence of human impacts in the highly sensitive and ecologically important Great Lakes of coastal NSW. This has involved the expansion of our collaboration to include Geoscience Australia; Contributions have been made to the IGBP HITE project. Further contributions will be made as the evidence gathered is drawn together and interpreted; Over the coming year, focus will be placed on completion of the investigation of the extent of aerial transport of trace elements across Tasmania over the last 200 years as well as evidence for human activity and impacts on the Great Lakes region of NSW. Further investigation of potential climate signals from sites in northern Australia will also be made. The first 12 months of data for all ACE-Asia radon and fine particle sites is now available with preliminary analyses performed; The seasonal variability of background radon concentration at each of the radon monitoring sites has been characterised for the available data; Major components related to industrial pollution and soil sources in China have been identified and quantified; Regional and seasonal variations and trends in aerosol constituents have been measured and compared across more than 2.8Mk2 of sampling area; The Hok Tsui and Kosan detectors were visited for general maintenance and recalibration; A grant application to the APN has been submitted in support of regional inventory analyses based on radon time series; Progress on the processing and interpretation of radon data was presented at the Cape Grim Science Meeting (6-7 February 2002) and the 7th Biennial SPERA Conference on

  12. U.S. Global Climate Change Impacts Report, Adaptation

    Science.gov (United States)

    Pulwarty, R.

    2009-12-01

    Adaptation measures improve our ability to cope with or avoid harmful climate impacts and take advantage of beneficial ones, now and as climate varies and changes. Adaptation and mitigation are necessary elements of an effective response to climate change. Adaptation options also have the potential to moderate harmful impacts of current and future climate variability and change. The Global Climate Change Impacts Report identifies examples of adaptation-related actions currently being pursued in various sectors and regions to address climate change, as well as other environmental problems that could be exacerbated by climate change such as urban air pollution and heat waves. Some adaptation options that are currently being pursued in various regions and sectors to deal with climate change and/or other environmental issues are identified in this report. A range of adaptation responses can be employed to reduce risks through redesign or relocation of infrastructure, sustainability of ecosystem services, increased redundancy of critical social services, and operational improvements. Adapting to climate change is an evolutionary process and requires both analytic and deliberative decision support. Many of the climate change impacts described in the report have economic consequences. A significant part of these consequences flow through public and private insurance markets, which essentially aggregate and distribute society's risk. However, in most cases, there is currently insufficient robust information to evaluate the practicality, efficiency, effectiveness, costs, or benefits of adaptation measures, highlighting a need for research. Adaptation planning efforts such as that being conducted in New York City and the Colorado River will be described. Climate will be continually changing, moving at a relatively rapid rate, outside the range to which society has adapted in the past. The precise amounts and timing of these changes will not be known with certainty. The

  13. Multi-wheat-model ensemble responses to interannual climatic variability

    DEFF Research Database (Denmark)

    Ruane, A C; Hudson, N I; Asseng, S;

    2016-01-01

    common characteristics of yield response to climate; however models rarely share the same cluster at all four sites indicating substantial independence. Only a weak relationship (R2 ≤ 0.24) was found between the models' sensitivities to interannual temperature variability and their response to long......We compare 27 wheat models' yield responses to interannual climate variability, analyzed at locations in Argentina, Australia, India, and The Netherlands as part of the Agricultural Model Intercomparison and Improvement Project (AgMIP) Wheat Pilot. Each model simulated 1981–2010 grain yield, and we...... evaluate results against the interannual variability of growing season temperature, precipitation, and solar radiation. The amount of information used for calibration has only a minor effect on most models' climate response, and even small multi-model ensembles prove beneficial. Wheat model clusters reveal...

  14. Adaptation to climate change and variability in Canadian water resources

    International Nuclear Information System (INIS)

    A survey is presented of topics and issues related to the adaptation to climate change in Canadian water resources. These resources are seen as especially sensitive to changes in variability in climate and hydrology. Based on current knowledge of global warming, significant changes in climate and hydrology are plausible within a time period that is significant for water resource management. Global warming will tend to exacerbate existing water resources problems in the southern Prairies and the Great Lakes. The Prairies can expect increased drought during summer, and the Great Lakes can expect a decline in mean lake levels to historic lows. Measures for adapting to climate change include traditional practices (supply management), which stress system reliability. They provide some adaptation to climate change but are limited in their ability to respond to rapid change. Nontraditional and non-management measures stress flexibility and resilience. These measures also address other concerns and can be implemented immediately, before the effects of climate change are evident. Water resources managers require methods of assessing the vulnerability of water resources systems to climate change to help identify when and where adaptive measures should be applied. Adaptation to climate change requires ongoing observation and interpretation of climate, hydrology, and related environmental processes. 29 refs., 1 fig., 3 tabs

  15. Local Perceptions of Climate Variability and Change in Tropical Forests of Papua, Indonesia

    Directory of Open Access Journals (Sweden)

    Manuel Boissière

    2013-12-01

    Full Text Available People everywhere experience changes and events that impact their lives. Knowing how they perceive, react, and adapt to climatic changes and events is helpful in developing strategies to support adaptation to climate change. Mamberamo in Papua, Indonesia, is a sparsely populated watershed of 7.8 million hectares possessing rich tropical forests. Our study compares scientific and traditional ecological knowledge (TEK on climate, and analyzes how local people in Mamberamo perceive and react to climatic variations. We compared meteorological data for the region with local views gathered through focus group discussions and interviews in six villages. We explored the local significance of seasonality, climate variability, and climate change. Mamberamo is subject to strikingly low levels of climatic variation; nonetheless local people highlighted certain problematic climate-related events such as floods and droughts. As our results illustrate, the implications vary markedly among villages. People currently consider climate variation to have little impact on their livelihoods when contrasted with other factors, e.g., logging, mining, infrastructure development, and political decentralization. Nonetheless, increased salinity of water supplies, crop loss due to floods, and reduced hunting success are concerns in specific villages. To gain local engagement, adaptation strategies should initially focus on factors that local people already judge important. Based on our results we demonstrate that TEK, and an assessment of local needs and concerns, provide practical insights for the development and promotion of locally relevant adaptation strategies. These insights offer a foundation for further engagement.

  16. Decadal climate variability in the eastern Caribbean

    Science.gov (United States)

    Jury, Mark R.; Gouirand, Isabelle

    2011-11-01

    Rainfall variability in the eastern Caribbean during the 20th century is analyzed using principal component analysis and singular value decomposition. In contrast to earlier studies that used seasonal data, here we employ continuous signal processing. The leading mode is a decadal oscillation related to third and fourth modes of sea level pressure (SLP) and sea surface temperatures (SST) which together identify three zones of action in the Atlantic: 35°N-20°N, 20°N-5°N, and 5°N-20°S. The ability of the ECHAM4.5 model to simulate this signal is investigated. Its decadal variability is also represented through lower-order SLP and SST modes that comprise an Atlantic tripole pattern with lower pressure east of the Caribbean. Composite analysis of high and low phases of the decadal mode reflects a cool east Pacific and a more active Atlantic Intertropical Convergence Zone during boreal summer, conditions that favor the intensification of African easterly waves. The decadal signal has strengthened since 1970, yet the three centers of action in Atlantic SST are relatively unsynchronized.

  17. Climate Informed Economic Instruments to Enhance Urban Water Supply Resilience to Hydroclimatological Variability and Change

    Science.gov (United States)

    Brown, C.; Carriquiry, M.; Souza Filho, F. A.

    2006-12-01

    Hydroclimatological variability presents acute challenges to urban water supply providers. The impact is often most severe in developing nations where hydrologic and climate variability can be very high, water demand is unmet and increasing, and the financial resources to mitigate the social effects of that variability are limited. Furthermore, existing urban water systems face a reduced solution space, constrained by competing and conflicting interests, such as irrigation demand, recreation and hydropower production, and new (relative to system design) demands to satisfy environmental flow requirements. These constraints magnify the impacts of hydroclimatic variability and increase the vulnerability of urban areas to climate change. The high economic and social costs of structural responses to hydrologic variability, such as groundwater utilization and the construction or expansion of dams, create a need for innovative alternatives. Advances in hydrologic and climate forecasting, and the increasing sophistication and acceptance of incentive-based mechanisms for achieving economically efficient water allocation offer potential for improving the resilience of existing water systems to the challenge of variable supply. This presentation will explore the performance of a system of climate informed economic instruments designed to facilitate the reduction of hydroclimatologic variability-induced impacts on water-sensitive stakeholders. The system is comprised of bulk water option contracts between urban water suppliers and agricultural users and insurance indexed on reservoir inflows designed to cover the financial needs of the water supplier in situations where the option is likely to be exercised. Contract and insurance parameters are linked to forecasts and the evolution of seasonal precipitation and streamflow and designed for financial and political viability. A simulation of system performance is presented based on ongoing work in Metro Manila, Philippines. The

  18. Climatic variables and malaria incidence in Dehradun, Uttaranchal, India

    Directory of Open Access Journals (Sweden)

    N. Pemola Devi ; R.K. Jauhari

    2006-03-01

    Full Text Available Background & objectives: Mosquito-borne diseases particularly malaria and Japanese encephalitis(JE are becoming most dreaded health problems in Dehradun district. Keeping in view that theclimatic factors particularly temperature and rainfall may alter the distribution of vector species–increasing or decreasing the ranges, depending on weather conditions that are favourable orunfavourable for mosquito breeding, it is aimed to find out the effect of climatic factors on malariaincidence with particular emphasis to capture the essential events as a result of climatic variability.Methods: Mosquito sampling and identification was done using WHO entomological methods andfollow-up of recognised keys and catalogues. Data on malaria incidence and meteorologicalinformation were gathered in a collaborative study with the District Malaria Office, and the ForestResearch Institute, Dehradun respectively. Pearson’s correlation analysis was applied for establishingrelationship between climate variables and malaria transmission.Results: Higher positive correlation of association was found between monthly parasite incidenceand climatic variables (temperature, rainfall and humidity. However, highest significant correlationwas found between rainfall and malaria incidence (r = 0.718, p < 0.0001 when the data were staggeredto allow a lag of one-month.Interpretation & conclusion: Climatic variables that predict the presence or absence of malaria arelikely to be the best suited for forecasting the distribution of this disease at the edges of its range

  19. Vegetation Interaction Enhances Interdecadal Climate Variability in the Sahel

    Science.gov (United States)

    Zeng, Ning; Neelin, J. David; Lau, William K.-M.

    1999-01-01

    The role of naturally varying vegetation in influencing the climate variability in the Sahel is explored in a coupled atmosphere-land-vegetation model. The Sahel rainfall variability is influenced by sea surface temperature (SST) variations in the oceans. Land-surface feedback is found to increase this variability both on interannual and interdecadal time scales. Interactive vegetation enhances the interdecadal variation significantly, but can reduce year to year variability due to a phase lag introduced by the relatively slow vegetation adjustment time. Variations in vegetation accompany the changes in rainfall, in particular, the multi-decadal drying trend from the 1950s to the 80s.

  20. Modeling Surgery: A New Way Toward Understanding Earth Climate Variability

    Institute of Scientific and Technical Information of China (English)

    WU Lixin; LIU Zhengyu; Robert Gallimore; Michael Notaro; Robert Jacob

    2005-01-01

    A new modeling concept, referred to as Modeling Surgery, has been recently developed at University of Wisconsin-Madison. It is specifically designed to diagnose coupled feedbacks between different climate components as well as climatic teleconnections within a specific component through systematically modifying the coupling configurations and teleconnective pathways. It thus provides a powerful means for identifying the causes and mechanisms of low-frequency variability in the Earth's climate system. In this paper, we will give a short review of our recent progress in this new area.

  1. Mediterranean climate variability during the Holocene

    Directory of Open Access Journals (Sweden)

    J.S.L. CASFORD

    2012-12-01

    Full Text Available We present a study on four high sedimentation-rate marine cores with suppressed bioturbation effects, recovered along the northern margin of the eastern Mediterranean. We demonstrate that this region, central to the development of modern civilisation, was substantially affected throughout the Holocene by a distinct cycle of cooling events on the order of 2o C. In the best-preserved cases the onset of these events appears particularly abrupt, within less than a century. The cooling events typically lasted several centuries, and there are compelling indications that they were associated with increased aridity in the Levantine/NE African sector (Rossignol-Strick, 1995; 1998; Alley et al., 1997; Hassan, 1986; 1996; 1997a,b; McKim Malville et al., 1998. Several of these episodes appear coincident with cultural reorganisations, with indigenous developments (eg. cattle domestication, new technologies and population migrations and fusion of peoples and ideas (Hassan, 1986; 1996; 1997a,b; McKim Malville, 1998. We infer that climatic events of a likely high-latitude origin (O’Brien et al., 1995; Bond et al., 1997; Mayewski et al., 1997; Alley et al., 1997 caused cooling and aridity in and around the eastern Mediterranean via a direct atmospheric link, and therefore played an important role in the development of modern civilisation.

  2. Climate change or variable weather: Rethinking Danish homeowners' perceptions of floods and climate

    DEFF Research Database (Denmark)

    Baron, Nina; Petersen, Lars Kjerulf

    2015-01-01

    understand homeowners’ perception of climate change and local flood risk. Ingold argues that those perceptions are shaped by people’s experiences with and connections to their local landscape. People experience the local variability of the weather, and not global climate change as presented in statistical...... approaches gives new insights as to why people living in flood-prone areas are not very concerned about climate change....

  3. Effects of interannual climate variability on tropical tree cover

    Science.gov (United States)

    Holmgren, Milena; Hirota, Marina; van Nes, Egbert H.; Scheffer, Marten

    2013-08-01

    Climatic warming is substantially intensifying the global water cycle and is projected to increase rainfall variability. Using satellite data, we show that higher climatic variability is associated with reduced tree cover in the wet tropics globally. In contrast, interannual variability in rainfall can have neutral or even positive effects on tree cover in the dry tropics. In South America, tree cover in dry lands is higher in areas with high year-to-year variability in rainfall. This is consistent with evidence from case studies suggesting that in these areas rare wet episodes are essential for opening windows of opportunity where massive tree recruitment can overwhelm disturbance effects, allowing the establishment of extensive woodlands. In Australia, wet extremes have similar effects, but the net effect of rainfall variability is overwhelmed by negative effects of extreme dry years. In Africa, effects of rainfall variability are neutral for dry lands. It is most likely that differences in herbivore communities and fire regimes contribute to regulating tree expansion during wet extremes. Our results illustrate that increasing climatic variability may affect ecosystem services in contrasting, and sometimes surprising, ways. Expansion of dry tropical tree cover during extreme wet events may decrease grassland productivity but enhance carbon sequestration, soil nutrient retention and biodiversity.

  4. The Impact of Solar Variability on Climate

    Science.gov (United States)

    Haigh

    1996-05-17

    A general circulation model that simulated changes in solar irradiance and stratospheric ozone was used to investigate the response of the atmosphere to the 11-year solar activity cycle. At solar maximum, a warming of the summer stratosphere was found to strengthen easterly winds, which penetrated into the equatorial upper troposphere, causing poleward shifts in the positions of the subtropical westerly jets, broadening of the tropical Hadley circulations, and poleward shifts of the storm tracks. These effects are similar to, although generally smaller in magnitude than, those observed in nature. A simulation in which only solar irradiance was changed showed a much weaker response. PMID:8662582

  5. Natural climate variability in a coupled model

    International Nuclear Information System (INIS)

    Multi-century simulations with a simplified coupled ocean-atmosphere model are described. These simulations reveal an impressive range of variability on decadal and longer time scales, in addition to the dominant interannual el Nino/Southern Oscillation signal that the model originally was designed to simulate. Based on a very large sample of century-long simulations, it is nonetheless possible to identify distinct model parameter sensitivities that are described here in terms of selected indices. Preliminary experiments motivated by general circulation model results for increasing greenhouse gases suggest a definite sensitivity to model global warming. While these results are not definitive, they strongly suggest that coupled air-sea dynamics figure prominently in global change and must be included in models for reliable predictions

  6. Implications of Climate Variability and Change for Smallholder Crop Production in Different Areas of Zimbabwe

    Directory of Open Access Journals (Sweden)

    K. Musiyiwa

    2014-08-01

    Full Text Available Sustainable food production in the rain-fed smallholder sector of Zimbabwe is imperative in current and future climates given the increasing proportion and role of the sector in food security. Backgrounds of the smallholder sector include low resource bases, declining soil productivity, climate variability and increasing human population. Impacts of climatic and non-climatic variables on crop production vary in different Agro-Ecological Regions (AERs. The study identifies the main climatic opportunities and constraints for sustainable rain-fed smallholder crop production systems in current and future climates. Estimated changes in rainfall and temperature by 2050 are not likely to negatively impact crop production in smallholder areas in AER I, increases in temperature may have negative impacts for most of AER III and IV. Most of AER V is likely to become unsuitable for sustainable maize production. Overall projections indicate increased differences in agricultural potential between smallholder farmers in AER I compared to those in AER II and III as well as those in AER IV and V and different management options. Proposed adaptation and coping strategies in AER I and some in AER II include intensification of agriculture and optimization of both C3 and C4 crop production while in AER III to V adoption of stress tolerant crops for family subsistence may be imperative.

  7. Grazing and climatic variability in Sajama National Park, Bolivia

    Directory of Open Access Journals (Sweden)

    Yager, K.

    2008-12-01

    Full Text Available Sajama National Park, the first protected area in Bolivia, includes five indigenous communities with a primary production base of pastoralism. The semi-arid region of the Central Andes is one of the most extreme areas of human occupation at 4200 meters altitude and affected by high climatic variability. This paper studies the relations between climate variability, resilience, biodiversity of pastures and pastoral production in Sajama National Park. We present a botanical study of palatable pasture herbs between two years, one humid (2006 and the other dry (2007. Thirty vascular plants were recorded. The number of species and the cover of iro (Festuca ortophylla peak in areas of intermediate disturbance; areas that are at a medium distance from camelid corrals. On the other hand, the cover of ephemeral plants between tussocks increases in high disturbance areas. This is interpreted as a result of the tradeoff between the damage of grazing and the benefit of the fertilization produced by the herding animals. The local people clearly perceive strong impacts of climate change, combined with changes in management and human pressures. The social dynamics and production management, combined with climate warming, water reduction, and the increasing variability of surface water regimes create potential risks for the local sustainability of pastoralism.

    El Parque Nacional Sajama, la primer área protegida de Bolivia, incluye a cinco comunidades indígenas con una base de producción principalmente de ganadería. Esta región semi-árida de los Andes Centrales es una de las áreas más extremas de ocupación humana a 4200 metros de altura y es afectada por una alta variabilidad climática. Este trabajo considera las relaciones entre la variabilidad climática, resiliencia, biodiversidad de pastos y la producción ganadera en el Parque Nacional Sajama. Presentamos un estudio botánico de las comunidades de hierbas palatables a lo largo de dos a

  8. Selecting representative climate models for climate change impact studies : An advanced envelope-based selection approach

    NARCIS (Netherlands)

    Lutz, Arthur F.; ter Maat, Herbert W.; Biemans, Hester; Shrestha, Arun B.; Wester, Philippus; Immerzeel, Walter W.

    2016-01-01

    Climate change impact studies depend on projections of future climate provided by climate models. The number of climate models is large and increasing, yet limitations in computational capacity make it necessary to compromise the number of climate models that can be included in a climate change impa

  9. Choosing and using climate change scenarios for ecological-impact assessments and conservation decisions

    Science.gov (United States)

    Amy K. Snover; Nathan J. Mantua; Littell, Jeremy; Michael A. Alexander; Michelle M. McClure; Janet Nye

    2013-01-01

    Increased concern over climate change is demonstrated by the many efforts to assess climate effects and develop adaptation strategies. Scientists, resource managers, and decision makers are increasingly expected to use climate information, but they struggle with its uncertainty. With the current proliferation of climate simulations and downscaling methods, scientifically credible strategies for selecting a subset for analysis and decision making are needed. Drawing on a rich literature in climate science and impact assessment and on experience working with natural resource scientists and decision makers, we devised guidelines for choosing climate-change scenarios for ecological impact assessment that recognize irreducible uncertainty in climate projections and address common misconceptions about this uncertainty. This approach involves identifying primary local climate drivers by climate sensitivity of the biological system of interest; determining appropriate sources of information for future changes in those drivers; considering how well processes controlling local climate are spatially resolved; and selecting scenarios based on considering observed emission trends, relative importance of natural climate variability, and risk tolerance and time horizon of the associated decision. The most appropriate scenarios for a particular analysis will not necessarily be the most appropriate for another due to differences in local climate drivers, biophysical linkages to climate, decision characteristics, and how well a model simulates the climate parameters and processes of interest. Given these complexities, we recommend interaction among climate scientists, natural and physical scientists, and decision makers throughout the process of choosing and using climate-change scenarios for ecological impact assessment.

  10. Impact of Wave Dragon on Wave Climate

    DEFF Research Database (Denmark)

    Andersen, Thomas Lykke; Tedd, James; Kramer, Morten;

    This report is an advisory paper for use in determining the wave dragon effects on hydrography, by considering the effect on the wave climate in the region of a wave dragon. This is to be used in the impact assessment for the Wave Dragon pre-commercial demonstrator....

  11. Climate impacts of Australian land cover change

    Science.gov (United States)

    Lawrence, P. J.

    2004-05-01

    Australian land cover has been dramatically altered since European settlement primarily for agricultural utilization, with native vegetation widely replaced or modified for cropping and intensive animal production. While there have been numerous investigations into the regional and near surface climate impacts of Australian land cover change, these investigation have not included the climate impacts of larger-scale changes in atmospheric circulation and their associated feedbacks, or the impacts of longer-term soil moisture feedbacks. In this research the CSIRO General Circulation Model (GCM) was used to investigate the climate impacts of Australian land cover change, with larger-scale and longer-term feedbacks. To avoid the common problem of overstating the magnitude and spatial extent of changes in land surface conditions prescribed in land cover change experiments, the current Australian land surface properties were described from finer-scale, satellite derived land cover datasets, with land surface conditions extrapolating from remnant native vegetation to pre-clearing extents to recreate the pre-clearing land surface properties. Aggregation rules were applied to the fine-scale data to generate the land surface parameters of the GCM, ensuring the equivalent sub-grid heterogeneity and land surface biogeophysics were captured in both the current and pre-clearing land surface parameters. The differences in climate simulated in the pre-clearing and current experiments were analyzed for changes in Australian continental and regional climate to assess the modeled climate impacts of Australian land cover change. The changes in modeled climate were compared to observed changes in Australian precipitation over the last 50 and 100 years to assess whether modeled results could be detected in the historical record. The differences in climate simulation also were analyzed at the global scale to assess the impacts of local changes on larger scale circulation and climate at

  12. Climatic impacts of anthropogenic aerosols

    Energy Technology Data Exchange (ETDEWEB)

    Iversen, T. [Oslo Univ. (Norway)

    1996-03-01

    This paper was read at the workshop ``The Norwegian Climate and Ozone Research Programme`` held on 11-12 March 1996. Anthropogenic production of aerosols is mainly connected with combustion of fossil fuel. Measured by particulate mass, the anthropogenic sulphate production is the dominating source of aerosols in the Northern Hemisphere. Particles emitted in mechanical processes, fly ash etc. are less important because of their shorter atmospheric residence time. Possible climatological effects of anthropogenic aerosols are usually classified in two groups: direct and indirect. Direct effects are alterations of the radiative heating budget due to the aerosol particles in clear air. Indirect effects involve the interaction between particles and cloud processes. A simplified one-layer radiation model gave cooling in the most polluted mid-latitude areas and heating due to soot absorption in the Arctic. This differential trend in heating rates may have significant effects on atmospheric meridional circulations, which is important for the atmosphere as a thermodynamic system. Recently the description of sulphur chemistry in the hemispheric scale dispersion model has been improved and will be used in a model for Mie scattering and absorption

  13. Climate Change Impacts on Turkish Vegetation

    Science.gov (United States)

    Forrest, Matthew; Dönmez, Cenk; Çilek, Ahmet; Akif Erdogan, Mehmet; Buontempo, Carlo; Hickler, Thomas

    2014-05-01

    The Mediterranean has been identified as a potentially vulnerable hotspot under climate change. In Turkey, climate change projections consistently predict large temperature rises over the 21st century. With 9% of GDP and 25% of employment coming from agriculture, climate change has the potential to significantly affect both the Turkish economy and living standards. Relatively little work has been undertaken to estimate the effects and risks of climate change in Turkey, and many European studies cover do not include the whole of Turkey in their domain and so are of limited use for policy-makers. The Dynamic Global Vegetation Model LPJ-GUESS was parametrised to represent Turkish vegetation. Climate forcings were derived by interpolating meteorological data from over 600 stations from 1975-2010 to a 1km resolution. Soil depth and soil texture data from field measurements were also interpolated to a 1km grid. The model was benchmarked against vegetation type and remotely sensed biomass and tree cover data. Future climate conditions were calculated using the outputs from a set of regional model simulations. In particular the HadRM3P regional climate model was used to downscale five members of a perturbed physics ensemble of global climate projections obtained using HadCM3 general circulation model and the SRES A1B scenario. A delta change factor approach was then used in conjunction with the observed climate data to assess the impact on vegetation structure and ecological processes to the year 2100 using LPJ-GUESS. The resulting changes to productivity, vegetation structure and hydrology are discussed. Eventually these results will be combined with complementary studies concerning wildfire and erosion to produce a risk map for informing policy-makers.

  14. Climate impacts of the ECLIPSE future emissions mitigation scenario

    Science.gov (United States)

    Baker, Laura; Collins, Bill; Olivie, Dirk; Cherian, Ribu; Quaas, Johannes; Myhre, Gunnar; Hodnebrog, Oivind; Skeie, Ragnhild

    2016-04-01

    We investigate the possible near-term climate benefits from mitigating aerosols, ozone and methane. The ECLIPSE (Evaluating the Climate and Air Quality Impacts of Short-Lived Pollutants) project developed a realistic emissions inventory based on current legislation for 2005-2050 (CLE), and a corresponding mitigation scenario designed to be beneficial for both air quality and short-term climate impact (MIT). We determine the climate impacts of the MIT scenario, focussing on the period 2040-2050. Four climate models with interactive chemistry and aerosols (HadGEM, NorESM, CESM-CAM4 and ECHAM-HAM) are used to provide multi-model ensembles of both atmosphere-only and coupled atmosphere-ocean simulations, to separate the effective radiative forcing (ERF) and the climate response. The ERFs are derived from the atmosphere-only simulations. In all models the MIT scenario leads to a negative global ERF which is driven mainly by methane emissions reductions. There is variability between models in the relative importance of methane and aerosol emissions reductions, and in the sign of ERF response to aerosol emissions reductions. The climate response to MIT is derived from the coupled simulations. In all models, MIT results in a decrease in the global mean temperature compared to CLE, with a model mean decrease of 0.22°C. The temperature decrease is seen most strongly in the Northern Hemisphere and is particularly strong in the Arctic. The ensembles of coupled-ocean simulations have therefore enabled us to identify a robust cooling signal from the air quality mitigation scenarios, which can be attributed to the different species using the ERFs.

  15. Impact of climate change and agriculture adaptation

    International Nuclear Information System (INIS)

    The author outlines and discusses the various impacts climate change can have on agriculture, notably due to the increase of CO2 and other greenhouse gases in the atmosphere, to temperature increase, to the modification of rainfalls, and therefore to differences in evaporation, drainage, run-off, cloud cover. He notably discusses the impact in terms of photosynthesis, of crop production in tempered or tropical regions. He also discusses the impact of extreme events (notably frost), comments how recent evolutions noticed by farmers could prefigure the future. He addresses the issue of adaptation which could mean a change of local practices or a displacement of activities

  16. 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

  17. Climate variability in West Greenland during the past 1500 years

    DEFF Research Database (Denmark)

    dos Santos Ribeiro, Sofia Isabel; Moros, Matthias; Ellegaard, Marianne;

    2012-01-01

    document late-Holocene climate variability in West Greenland as inferred from a marine sediment record from the outer Disko Bay. Organic-walled dinoflagellate cysts and other palynomorphs were used to reconstruct environmental changes in the area through the last c. 1500 years at 30–40 years resolution....... Sea ice cover and primary productivity were identified as the two main factors driving dinoflagellate cyst community changes through time. Our data provide evidence for an opposite climate trend in West Greenland relative to the NE Atlantic region from c. AD 500 to 1050. For the same period, sea......Ribeiro, S., Moros, M., Ellegaard, M. & Kuijpers, A. 2012 (January): Climate variability in West Greenland during the past 1500 years: evidence from a high-resolution marine palynological record from Disko Bay. Boreas, Vol. 41, pp. 68–83. 10.1111/j.1502-3885.2011.00216.x. ISSN 0300-9483. Here we...

  18. Revealing Relationships among Relevant Climate Variables with Information Theory

    CERN Document Server

    Knuth, Kevin H; Curry, Charles T; Huyser, Karen A; Wheeler, Kevin R; Rossow, William B

    2013-01-01

    A primary objective of the NASA Earth-Sun Exploration Technology Office is to understand the observed Earth climate variability, thus enabling the determination and prediction of the climate's response to both natural and human-induced forcing. We are currently developing a suite of computational tools that will allow researchers to calculate, from data, a variety of information-theoretic quantities such as mutual information, which can be used to identify relationships among climate variables, and transfer entropy, which indicates the possibility of causal interactions. Our tools estimate these quantities along with their associated error bars, the latter of which is critical for describing the degree of uncertainty in the estimates. This work is based upon optimal binning techniques that we have developed for piecewise-constant, histogram-style models of the underlying density functions. Two useful side benefits have already been discovered. The first allows a researcher to determine whether there exist suf...

  19. Global climate models’ bias in surface temperature trends and variability

    International Nuclear Information System (INIS)

    The Earth has warmed in the last century with the most rapid warming occurring near the surface in the Arctic. This Arctic amplification occurs partly because the extra heat is trapped in a thin layer of air near the surface due to the persistent stable-stratification found in this region. The amount of warming depends upon the extent of turbulent mixing in the atmosphere, which is described by the depth of the atmospheric boundary layer (ABL). Global climate models (GCMs) tend to over-estimate the depth of stably-stratified ABLs, and here we show that GCM biases in the ABL depth are strongly correlated with biases in the surface temperature variability. This highlights the need for a better description of the stably-stratified ABL in GCMs in order to constrain the current uncertainty in climate variability and projections of climate change in the surface layer. (letter)

  20. Relationship between ozon changes and solar variability through climate observation

    International Nuclear Information System (INIS)

    A number of photo model studies of the earth's atmosphere have raised the possibility that atmospheric O3 concentrations may be altered significantly by antropogenic sources of trace chemical species and by solar variability. The possible climatic effect of such O3, perturbations, as they are understood currently, are reviewed. A change in tropospheric O3 can influence the tropospheric climate directly through its effect on tropospheric radiative heating, where as stratospheric O3 change exerts its influence on the tropospheric climate through radiative and dynamical coupling mechanics. Changes in both tropospheric and stratospheric O3 are considered and model result are described for their effects on: surface temperature, surface tropospheric radiative heating, and vertical and latitudinal temperature gradients within the stratosphere. The solar variability effects on stratospheric temperature gradients and on radiative dissipation rates are discussed

  1. Regional climate model simulations indicate limited climatic impacts by operational and planned European wind farms.

    Science.gov (United States)

    Vautard, Robert; Thais, Françoise; Tobin, Isabelle; Bréon, François-Marie; Devezeaux de Lavergne, Jean-Guy; Colette, Augustin; Yiou, Pascal; Ruti, Paolo Michele

    2014-01-01

    The rapid development of wind energy has raised concerns about environmental impacts. Temperature changes are found in the vicinity of wind farms and previous simulations have suggested that large-scale wind farms could alter regional climate. However, assessments of the effects of realistic wind power development scenarios at the scale of a continent are missing. Here we simulate the impacts of current and near-future wind energy production according to European Union energy and climate policies. We use a regional climate model describing the interactions between turbines and the atmosphere, and find limited impacts. A statistically significant signal is only found in winter, with changes within ±0.3 °C and within 0-5% for precipitation. It results from the combination of local wind farm effects and changes due to a weak, but robust, anticyclonic-induced circulation over Europe. However, the impacts remain much weaker than the natural climate interannual variability and changes expected from greenhouse gas emissions. PMID:24518587

  2. Uncertainty in soil data can outweigh climate impact signals in global crop yield simulations

    Science.gov (United States)

    Folberth, Christian; Skalský, Rastislav; Moltchanova, Elena; Balkovič, Juraj; Azevedo, Ligia B.; Obersteiner, Michael; van der Velde, Marijn

    2016-06-01

    Global gridded crop models (GGCMs) are increasingly used for agro-environmental assessments and estimates of climate change impacts on food production. Recently, the influence of climate data and weather variability on GGCM outcomes has come under detailed scrutiny, unlike the influence of soil data. Here we compare yield variability caused by the soil type selected for GGCM simulations to weather-induced yield variability. Without fertilizer application, soil-type-related yield variability generally outweighs the simulated inter-annual variability in yield due to weather. Increasing applications of fertilizer and irrigation reduce this variability until it is practically negligible. Importantly, estimated climate change effects on yield can be either negative or positive depending on the chosen soil type. Soils thus have the capacity to either buffer or amplify these impacts. Our findings call for improvements in soil data available for crop modelling and more explicit accounting for soil variability in GGCM simulations.

  3. Simple emission metrics for climate impacts

    Directory of Open Access Journals (Sweden)

    B. Aamaas

    2013-06-01

    Full Text Available In the context of climate change, emissions of different species (e.g., carbon dioxide and methane are not directly comparable since they have different radiative efficiencies and lifetimes. Since comparisons via detailed climate models are computationally expensive and complex, emission metrics were developed to allow a simple and straightforward comparison of the estimated climate impacts of emissions of different species. Emission metrics are not unique and variety of different emission metrics has been proposed, with key choices being the climate impacts and time horizon to use for comparisons. In this paper, we present analytical expressions and describe how to calculate common emission metrics for different species. We include the climate metrics radiative forcing, integrated radiative forcing, temperature change and integrated temperature change in both absolute form and normalised to a reference gas. We consider pulse emissions, sustained emissions and emission scenarios. The species are separated into three types: CO2 which has a complex decay over time, species with a simple exponential decay, and ozone precursors (NOx, CO, VOC which indirectly effect climate via various chemical interactions. We also discuss deriving Impulse Response Functions, radiative efficiency, regional dependencies, consistency within and between metrics and uncertainties. We perform various applications to highlight key applications of emission metrics, which show that emissions of CO2 are important regardless of what metric and time horizon is used, but that the importance of short lived climate forcers varies greatly depending on the metric choices made. Further, the ranking of countries by emissions changes very little with different metrics despite large differences in metric values, except for the shortest time horizons (GWP20.

  4. Adaptation to climate change and climate variability:The importance of understanding agriculture as performance

    NARCIS (Netherlands)

    Crane, T.A.; Roncoli, C.; Hoogenboom, G.

    2011-01-01

    Most climate change studies that address potential impacts and potential adaptation strategies are largely based on modelling technologies. While models are useful for visualizing potential future outcomes and evaluating options for potential adaptation, they do not adequately represent and integrat

  5. Response of closed basin lakes to interannual climate variability

    Science.gov (United States)

    Huybers, Kathleen; Rupper, Summer; Roe, Gerard H.

    2016-06-01

    Lakes are key indicators of a region's hydrological cycle, directly reflecting the basin-wide balance between precipitation and evaporation. Lake-level records are therefore valuable repositories of climate history. However, the interpretation of such records is not necessarily straightforward. Lakes act as integrators of the year-to-year fluctuations in precipitation and evaporation that occur even in a constant climate. Therefore lake levels can exhibit natural, unforced fluctuations that persist on timescales of decades or more. This behavior is important to account for when distinguishing between true climate change and interannual variability as the cause of past lake-level fluctuations. We demonstrate the operation of this general principle for the particular case-study of the Great Salt Lake, which has long historical lake-level and climatological records. We employ both full water-balance and linear models. Both models capture the timing and size of the lake's historical variations. We then model the lake's response to much longer synthetic time series of precipitation and evaporation calibrated to the observations, and compare the magnitude and frequency of the modeled response to the Great Salt Lake's historical record. We find that interannual climate variability alone can explain much of the decadal-to-centennial variations in the lake-level record. Further, analytic solutions to the linear model capture much of the full model's behavior, but fail to predict the most extreme lake-level variations. We then apply the models to other lake geometries, and evaluate how the timing and amplitude of a lake-level response differs with climatic and geometric setting. A lake's response to a true climatic shift can only be understood in the context of these expected persistent lake-level variations. On the basis of these results, we speculate that lake response to interannual climate variability may play an important part in explaining much of Holocene lake

  6. Are we overestimating the effect of large-scale indices of climate variability in floods and droughts in Europe?

    Science.gov (United States)

    Guimarães Nobre, Gabriela; Aerts, Jeroen; Ward, Philip J.

    2016-04-01

    Large-scale climate oscillation is known to influence local and regional climate, and has the potential to trigger flood and drought hazards. Therefore, atmospheric indices of climate oscillation such as ENSO, NAO and AO are often associated with an increase in the burden of natural disasters, and frequently fuel societal distress. Since climate variability is responsible for a great amount of variability in hydro- climatological events, it also influences the (medium term-) forecastability of local weather conditions and extreme events. This study will examine a range of a large-scale indices of climate variability during their neutral and informed phases (either positive and negative) aiming at answering the following research questions: Has climate oscillation increased the frequency of flood and drought disasters in Europe between 1980 and 2014? Are climate informed years linked to a higher number of hydrological and climatological extreme events? Is there a change in flood and drought impacts between different phases? For the analysis, different indices of climate oscillation (ENSO, NAO and AO) will be applied in order to verify whether there is predominant climate oscillation acting in both pan European floods and droughts , and their effect on flood damages and crop productivity, respectively. Using event specific disaster losses data, hydrological and climate information, and crop yield data, we expect to understand how large the influence is of large-scale indices of climate variability in natural hazards, and to perceive the harm or benefit of climate oscillation in the agricultural sector and the damages from floods to urban areas. Through the comprehension of the relationship between large scale climate variability and pan European flood damages and drought related agricultural impact, this study reflects on how this information could be potentially applied to improve flood and drought management by coupling such finds with seasonal forecasting of

  7. The impacts of climate change in Aquitaine

    International Nuclear Information System (INIS)

    This article presents a book which addresses the impacts of climate change in the Aquitaine region by 2030-2050 in order to prepare the adaptation of the main economic sectors. Several fields are addressed: agriculture and wine-growing, forestry, estuaries, coasts and sea resources. The book examines two aspects of climate change due to greenhouse gas emissions: mitigation and adaptation. Two scenarios are studied: a global temperature increase of 2 degrees, and a global temperature increase between 4 and 5 degrees. As examples of this study, this article gives an overview of these issues of mitigation and adaptation in four domains: forests, wine-growing, air quality, and health

  8. Climatic impact of aircraft induced ozone changes

    Energy Technology Data Exchange (ETDEWEB)

    Sausen, R.; Feneberg, B.; Ponater, M. [Deutsche Forschungs- und Versuchsanstalt fuer Luft- und Raumfahrt e.V., Oberpfaffenhofen (Germany). Inst. fuer Physik der Atmosphaere

    1997-12-31

    The effect of aircraft induced ozone changes on the global climate is studied by means of the general circulation model ECHAM4. The zonal mean temperature signal is considered. In order to estimate the statistical significance of the climatic impact a multivariate statistical test hierarchy combined with the fingerprint method has been applied. Sensitivity experiments show a significant coherent temperature response pattern in the northern extra-tropics for mid-latitude summer conditions. It consists of a tropospheric warming of about 0.2 K with a corresponding stratospheric cooling of the same magnitude. (author) 16 refs.

  9. CLIMATE CHANGE IMPACTS ON WATER RESOURCES

    OpenAIRE

    T.M. CORNEA; Dima, M.; Roca, D.

    2011-01-01

    Climate change impacts on water resources – The most recent scientific assessment by the Intergovernmental Panel on Climate Change (IPCC) [6] concludes that, since the late 19th century, anthropogenic induced emissions of greenhouse gases have contributed to an increase in global surface temperatures of about 0.3 to 0.6o C. Based on the IPCC’s scenario of future greenhouse gas emissions and aerosols a further increase of 2o C is expected by the year 2100. Plants, animals, natural and managed ...

  10. Climate Impacts of the Paris Agreement

    Science.gov (United States)

    Sokolov, Andrei; Paltsev, Sergey; Chen, Henry; Monier, Erwan

    2016-04-01

    The UN agreement signed during the recent COP21 meeting in Paris defines policies which supposed to be implemented by different countries to reduce their anthropogenic greenhouse gas (GHG) emissions. Those agreed policies, however, only cover the period up to 2030 and they do not specify actions after 2030. As a result, projections of the long-term climate impact of the Paris agreement produced by different research groups differ significantly because they make different assumptions about the policies after 2030. In this study we estimate possible impacts using the MIT Integrated Global System Model, which consists of the human activity model, Economic Projection and Policy Analysis (EPPA) model, and a climate model of intermediate complexity, the MIT Earth System Model (MESM). In addition to the "no climate policy" scenario, we consider a scenario that incorporates the emissions targets proposed by the international community to address the challenges of climate change based on the submissions to the COP21 process. For the post-2030 period we create several variations: a) no additional climate policy after 2030, but the proposed cuts are extended to 2100; b) reductions in emissions and emission intensities after 2030 at the same rate as in the 2020-2030 period; 3) in addition to the conditions in the previous no country increases its GHG emissions after 2050. Based on the emission scenarios, we simulate possible future climate changes. Our analysis shows that, for the climate parameters corresponding to the median strength of the climate system response to anthropogenic forcing, the Paris Agreement can reduce the global mean surface air temperature (SAT) in 2100 between 0.63 and 1.07oC relative to "no climate policy" case. At the same time, due to a large inertia of climate system, in 2050 the SAT reduced only by about 0.12oC under all three scenarios. Under all three variants of an extension of the Paris Agreement an increase in the SAT relative to an 1861

  11. Coping Strategies to Deal with Environmental Variability and Extreme Climatic Events in the Peruvian Anchovy Fishery

    Directory of Open Access Journals (Sweden)

    Marilú Bouchon

    2011-06-01

    Full Text Available The Peruvian anchovy fishery is the largest worldwide in terms of catches. The fishery started during the mid 1950s, and since then it has been highly dependent on natural stock fluctuations, due to the sensitivity of anchovy stocks to ocean-climate variability. The main driver of anchovy stock variability is the El Niño Southern Oscillation (ENSO, and three extreme ENSO warm events were recorded in 1972–1973, 1983–1984 and 1997–1998. This study investigates the evolution of coping strategies developed by the anchovy fisheries to deal with climate variability and extreme ENSO events. Results showed eight coping strategies to reduce impacts on the fishery. These included: decentralized installation of anchovy processing factories; simultaneous ownership of fishing fleet and processing factories; use of low-cost unloading facilities; opportunistic utilization of invading fish populations; low cost intensive monitoring; rapid flexible management; reduction of fishmeal price uncertainty through controlled production based on market demand; and decoupling of fishmeal prices from those of other protein-rich feed substitutes like soybean. This research shows that there are concrete lessons to be learned from successful adaptations to cope with climate change-related extreme climatic events that impact the supply of natural resources. The lessons can contribute to improved policies for coping with climate change in the commercial fishery sector.

  12. To what extent is climate change detection at the local scale 'clouded' by internal variability?

    Science.gov (United States)

    Aalbers, Emma; Lenderink, Geert; van Meijgaard, Erik; van den Hurk, Bart

    2016-04-01

    Internal variability, i.e. the natural variability of the climate system, has been shown to be an important source of uncertainty in climate change projections of mean and (especially) extreme climate events, next to model uncertainty and uncertainty in projections of greenhouse gas emissions. To quantify the internal variability and get a robust estimate of the forced climate change response, large ensembles of climate model simulations of the same model provide essential information. For global climate models (GCMs) a number of these single model ensembles are indeed available. So far however, the size of single model ensembles for regional climate models (RCMs) has been limited to only a few members, relatively short periods or small modeling domains. Here, we use a 16 member ensemble generated with the RCM KNMI-RACMO2 driven by the GCM EC-EARTH. The initial atmospheric state of EC-EARTH was perturbed in 1850, after which each member was run until 2100 assuming the historical emission scenario until 2005 and the RCP8.5 emission scenario from 2006 onwards. Each of the EC-EARTH members was then downscaled on a 12-km resolved domain covering Western Europe including the Alps for the period 1950-2100. For this ensemble we show the climate change signal, the noise due to internal variability and the signal-to-noise ratio, and how these depend on parameter, season, location and projection period. Using an aggregated spatial probability perspective similar to Fischer et al. (2013) we also examine whether spatially aggregated responses yield more robust changes and earlier detection times of climate change. This information is particularly relevant when the output of RCMs is applied in impact studies. Firstly, with this information we can identify which of the two - internal variability or climate change - is more important for a certain timescale, requiring potentially different coping strategies. Secondly, the internal variability can be a cause for the discrepancy

  13. Mechanisms of change in ENSO-induced tropical Pacific rainfall variability in a warming climate

    Science.gov (United States)

    Huang, Ping; Xie, Shang-Ping

    2015-12-01

    El Niño/Southern Oscillation (ENSO) is a mode of natural variability that has considerable impacts on global climate and ecosystems, through rainfall variability in the tropical Pacific and atmospheric teleconnections. In response to global warming, ENSO-driven rainfall variability is projected to intensify over the central-eastern Pacific but weaken over the western Pacific, whereas ENSO-related sea surface temperature variability is projected to decrease. Here, we explore the mechanisms that lead to changes in ENSO-driven rainfall variability in the tropical Pacific in response to global warming, with the help of a moisture budget decomposition for simulations from eighteen state-of-the-art climate models. We identify two opposing mechanisms that approximately offset each other: the increase in mean-state moisture content associated with surface warming strengthens ENSO-related rainfall anomalies, whereas the projected reduction in ENSO-related variability of sea surface temperatures suppresses rainfall. Two additional effects--spatially non-uniform changes in background sea surface temperatures and structural changes in sea surface temperature related to ENSO--both enhance central-eastern Pacific rainfall variability while dampening variability in the western Pacific, in nearly equal amounts. Our decomposition method may be generalized to investigate how rainfall variability would change owing to nonlinear interactions between background sea surface temperatures and their variability.

  14. Climate change impacts and risks for animal health in Asia.

    Science.gov (United States)

    Forman, S; Hungerford, N; Yamakawa, M; Yanase, T; Tsai, H-J; Joo, Y-S; Yang, D-K; Nha, J-J

    2008-08-01

    The threat of climate change and global warming is now recognised worldwide and some alarming manifestations of change have occurred. The Asian continent, because of its size and diversity, may be affected significantly by the consequences of climate change, and its new status as a 'hub' of livestock production gives it an important role in mitigating possible impacts of climate variability on animal health. Animal health may be affected by climate change in four ways: heat-related diseases and stress, extreme weather events, adaptation of animal production systems to new environments, and emergence or re-emergence of infectious diseases, especially vector-borne diseases critically dependent on environmental and climatic conditions. To face these new menaces, the need for strong and efficient Veterinary Services is irrefutable, combined with good coordination of public health services, as many emerging human diseases are zoonoses. Asian developing countries have acute weaknesses in their Veterinary Services, which jeopardises the global surveillance network essential for early detection of hazards. Indeed, international cooperation within and outside Asia is vital to mitigating the risks of climate change to animal health in Asia. PMID:18819679

  15. Effects of climate variability on global scale flood risk

    Science.gov (United States)

    Ward, P.; Dettinger, M. D.; Kummu, M.; Jongman, B.; Sperna Weiland, F.; Winsemius, H.

    2013-12-01

    In this contribution we demonstrate the influence of climate variability on flood risk. Globally, flooding is one of the worst natural hazards in terms of economic damages; Munich Re estimates global losses in the last decade to be in excess of $240 billion. As a result, scientifically sound estimates of flood risk at the largest scales are increasingly needed by industry (including multinational companies and the insurance industry) and policy communities. Several assessments of global scale flood risk under current and conditions have recently become available, and this year has seen the first studies assessing how flood risk may change in the future due to global change. However, the influence of climate variability on flood risk has as yet hardly been studied, despite the fact that: (a) in other fields (drought, hurricane damage, food production) this variability is as important for policy and practice as long term change; and (b) climate variability has a strong influence in peak riverflows around the world. To address this issue, this contribution illustrates the influence of ENSO-driven climate variability on flood risk, at both the globally aggregated scale and the scale of countries and large river basins. Although it exerts significant and widespread influences on flood peak discharges in many parts of the world, we show that ENSO does not have a statistically significant influence on flood risk once aggregated to global totals. At the scale of individual countries, though, strong relationships exist over large parts of the Earth's surface. For example, we find particularly strong anomalies of flood risk in El Niño or La Niña years (compared to all years) in southern Africa, parts of western Africa, Australia, parts of Central Eurasia (especially for El Niño), the western USA (especially for La Niña), and parts of South America. These findings have large implications for both decadal climate-risk projections and long-term future climate change

  16. The importance of including variability in climate change projections used for adaptation

    Science.gov (United States)

    Sexton, David M. H.; Harris, Glen R.

    2015-10-01

    Our understanding of mankind’s influence on the climate is largely based on computer simulations. Model output is typically averaged over several decades so that the anthropogenic climate change signal stands out from the largely unpredictable `noise’ of climate variability. Similar averaging periods (30-year) are used for regional climate projections to inform adaptation. According to two such projections, UKCIP02 (ref. ) and UKCP09 (ref. ), the UK will experience `hotter drier summers and warmer wetter winters’ in the future. This message is about a typical rather than any individual future season, and these projections should not be compared directly to observed weather as this neglects the sizeable contribution from year-to-year climate variability. Therefore, despite the apparent contradiction with the messages, it is a fallacy to suggest the recent cold UK winters like 2009/2010 disprove human-made climate change. Nevertheless, such claims understandably cause public confusion and doubt. Here we include year-to-year variability to provide projections for individual seasons. This approach has two advantages. First, it allows fair comparisons with recent weather events, for instance showing that recent cold winters are within projected ranges. Second, it allows the projections to be expressed in terms of the extreme hot, cold, wet or dry seasons that impact society, providing a better idea of adaptation needs.

  17. Regional climate impacts of a possible future grand solar minimum.

    Science.gov (United States)

    Ineson, Sarah; Maycock, Amanda C; Gray, Lesley J; Scaife, Adam A; Dunstone, Nick J; Harder, Jerald W; Knight, Jeff R; Lockwood, Mike; Manners, James C; Wood, Richard A

    2015-01-01

    Any reduction in global mean near-surface temperature due to a future decline in solar activity is likely to be a small fraction of projected anthropogenic warming. However, variability in ultraviolet solar irradiance is linked to modulation of the Arctic and North Atlantic Oscillations, suggesting the potential for larger regional surface climate effects. Here, we explore possible impacts through two experiments designed to bracket uncertainty in ultraviolet irradiance in a scenario in which future solar activity decreases to Maunder Minimum-like conditions by 2050. Both experiments show regional structure in the wintertime response, resembling the North Atlantic Oscillation, with enhanced relative cooling over northern Eurasia and the eastern United States. For a high-end decline in solar ultraviolet irradiance, the impact on winter northern European surface temperatures over the late twenty-first century could be a significant fraction of the difference in climate change between plausible AR5 scenarios of greenhouse gas concentrations. PMID:26102364

  18. Climate-induced interannual variability of marine primary and export production in three global coupled climate carbon cycle models

    Directory of Open Access Journals (Sweden)

    B. Schneider

    2008-04-01

    Full Text Available Fully coupled climate carbon cycle models are sophisticated tools that are used to predict future climate change and its impact on the land and ocean carbon cycles. These models should be able to adequately represent natural variability, requiring model validation by observations. The present study focuses on the ocean carbon cycle component, in particular the spatial and temporal variability in net primary productivity (PP and export production (EP of particulate organic carbon (POC. Results from three coupled climate carbon cycle models (IPSL, MPIM, NCAR are compared with observation-based estimates derived from satellite measurements of ocean colour and results from inverse modelling (data assimilation. Satellite observations of ocean colour have shown that temporal variability of PP on the global scale is largely dominated by the permanently stratified, low-latitude ocean (Behrenfeld et al., 2006 with stronger stratification (higher sea surface temperature; SST being associated with negative PP anomalies. Results from all three coupled models confirm the role of the low-latitude, permanently stratified ocean for anomalies in globally integrated PP, but only one model (IPSL also reproduces the inverse relationship between stratification (SST and PP. An adequate representation of iron and macronutrient co-limitation of phytoplankton growth in the tropical ocean has shown to be the crucial mechanism determining the capability of the models to reproduce observed interactions between climate and PP.

  19. Can adaptation to climate variability and change be combined with mitigation of emissions at the local level?

    OpenAIRE

    Neupane, Bijaya

    2013-01-01

    This research investigated how community forest user groups at two sites in Nepal adapt with local weather events and climate variability, and the major factors that affected adaptive capacity of local people. Besides, this research identified to what extent the community forests could help in managing climate variability that impact on sustainable livelihood by improving the adaptive capacity of local people. This study also quantified the total above ground carbon sequestrated by two commun...

  20. Climate dynamics and fluid mechanics: Natural variability and related uncertainties

    CERN Document Server

    Ghil, Michael; Simonnet, Eric; 10.1016/j.physd.2008.03.036

    2010-01-01

    The purpose of this review-and-research paper is twofold: (i) to review the role played in climate dynamics by fluid-dynamical models; and (ii) to contribute to the understanding and reduction of the uncertainties in future climate-change projections. To illustrate the first point, we focus on the large-scale, wind-driven flow of the mid-latitude oceans which contribute in a crucial way to Earth's climate, and to changes therein. We study the low-frequency variability (LFV) of the wind-driven, double-gyre circulation in mid-latitude ocean basins, via the bifurcation sequence that leads from steady states through periodic solutions and on to the chaotic, irregular flows documented in the observations. This sequence involves local, pitchfork and Hopf bifurcations, as well as global, homoclinic ones. The natural climate variability induced by the LFV of the ocean circulation is but one of the causes of uncertainties in climate projections. Another major cause of such uncertainties could reside in the structural ...

  1. Mid-Holocene regional reorganization of climate variability

    Directory of Open Access Journals (Sweden)

    K. W. Wirtz

    2009-01-01

    Full Text Available We integrate 130 globally distributed proxy time series to refine the understanding of climate variability during the Holocene. Cyclic anomalies and temporal trends in periodicity from the Lower to the Upper Holocene are extracted by combining Lomb-Scargle Fourier-transformed spectra with bootstrapping. Results were cross-checked by counting events in the time series. Main outcomes are: First, the propensity of the climate system to fluctuations is a region specific property. Many records of adjacent sites reveal a similar change in variability although they belong to different proxy types (e.g., δ18O, lithic composition. Secondly, at most sites, irreversible change occured in the Mid-Holocene. We suggest that altered ocean circulation together with slightly modified coupling intensity between regional climate subsystems around the 5.5 kyr BP event (termination of the African Humid Period were responsible for the shift. Fluctuations especially intensified along a pan-American corridor. This may have led to an unequal crisis probability for early human civilizations in the Old and New World. Our study did not produce evidence for millennial scale cyclicity in some solar activity proxies for the Upper Holocene, nor for a privileged role of the prominent 250, 550, 900 and 1450 yr cycles. This lack of global periodicities corroborates the regional character of climate variability.

  2. Sensitivity of Climate Change Detection and Attribution to the Characterization of Internal Climate Variability

    KAUST Repository

    Imbers, Jara

    2014-05-01

    The Intergovernmental Panel on Climate Change\\'s (IPCC) "very likely" statement that anthropogenic emissions are affecting climate is based on a statistical detection and attribution methodology that strongly depends on the characterization of internal climate variability. In this paper, the authors test the robustness of this statement in the case of global mean surface air temperature, under different representations of such variability. The contributions of the different natural and anthropogenic forcings to the global mean surface air temperature response are computed using a box diffusion model. Representations of internal climate variability are explored using simple stochastic models that nevertheless span a representative range of plausible temporal autocorrelation structures, including the short-memory first-order autoregressive [AR(1)] process and the long-memory fractionally differencing process. The authors find that, independently of the representation chosen, the greenhouse gas signal remains statistically significant under the detection model employed in this paper. The results support the robustness of the IPCC detection and attribution statement for global mean temperature change under different characterizations of internal variability, but they also suggest that a wider variety of robustness tests, other than simple comparisons of residual variance, should be performed when dealing with other climate variables and/or different spatial scales. © 2014 American Meteorological Society.

  3. The role of internal climate variability for interpreting climate change scenarios

    Science.gov (United States)

    Maraun, Douglas

    2013-04-01

    When communicating information on climate change, the use of multi-model ensembles has been advocated to sample uncertainties over a range as wide as possible. To meet the demand for easily accessible results, the ensemble is often summarised by its multi-model mean signal. In rare cases, additional uncertainty measures are given to avoid loosing all information on the ensemble spread, e.g., the highest and lowest projected values. Such approaches, however, disregard the fundamentally different nature of the different types of uncertainties and might cause wrong interpretations and subsequently wrong decisions for adaptation. Whereas scenario and climate model uncertainties are of epistemic nature, i.e., caused by an in principle reducible lack of knowledge, uncertainties due to internal climate variability are aleatory, i.e., inherently stochastic and irreducible. As wisely stated in the proverb "climate is what you expect, weather is what you get", a specific region will experience one stochastic realisation of the climate system, but never exactly the expected climate change signal as given by a multi model mean. Depending on the meteorological variable, region and lead time, the signal might be strong or weak compared to the stochastic component. In cases of a low signal-to-noise ratio, even if the climate change signal is a well defined trend, no trends or even opposite trends might be experienced. Here I propose to use the time of emergence (TOE) to quantify and communicate when climate change trends will exceed the internal variability. The TOE provides a useful measure for end users to assess the time horizon for implementing adaptation measures. Furthermore, internal variability is scale dependent - the more local the scale, the stronger the influence of internal climate variability. Thus investigating the TOE as a function of spatial scale could help to assess the required spatial scale for implementing adaptation measures. I exemplify this proposal with

  4. Gulf Coast hurricane activity and climate variability during the last half of the Holocene

    Science.gov (United States)

    Lane, P.; Donnelly, J. P.

    2011-12-01

    The dominant timescales of variability in a 4500-year sediment-based storm chronology from the northeastern Gulf of Mexico are identified, and relationships between storm frequency and climate are explored. Changes in the frequency of large storm surge deposits in the record likely represent variability in the intensity distribution of hurricanes impacting the site during the late Holocene. Significant variability at approximately 200 and 1000-year timescales that was detected in the storm record is shared by numerous Holocene climate records including reconstructions of Loop Current penetration into the Gulf of Mexico. Intense storm landfalls were most frequent around 3.7 ka, between 2.7 and 2.4 ka, and around 0.7 ka when foraminiferal proxies of mixed layer depth indicate a more permanent residence of the Loop Current within the northeastern Gulf. Migrations of the Loop Current would exercise control over regional hurricane activity by changing the thermal structure of the upper ocean and influencing the role of storm-induced upwelling on hurricane intensification. Other factors that influenced regional and Atlantic basin-wide hurricane activity include the El Niño/Southern Oscillation and the position of the Inter-Tropical Convergence Zone. Many authors have suggested that bicentennial and millennial-scale climate variability may have been driven ultimately by changes in solar irradiance. Thus, low-frequency variability in Atlantic hurricane activity may be an expression of the climate system's response to exogenous forcing.

  5. Variable climatic conditions dominate recent phytoplankton dynamics in Chesapeake Bay

    Science.gov (United States)

    Harding, Lawrence W., Jr.; Mallonee, Michael E.; Perry, Elgin S.; Miller, W. David; Adolf, Jason E.; Gallegos, Charles L.; Paerl, Hans W.

    2016-03-01

    Variable climatic conditions strongly influence phytoplankton dynamics in estuaries globally. Our study area is Chesapeake Bay, a highly productive ecosystem providing natural resources, transportation, and recreation for nearly 16 million people inhabiting a 165,000-km2 watershed. Since World War II, nutrient over-enrichment has led to multiple ecosystem impairments caused by increased phytoplankton biomass as chlorophyll-a (chl-a). Doubled nitrogen (N) loadings from 1945–1980 led to increased chl-a, reduced water clarity, and low dissolved oxygen (DO), while decreased N loadings from 1981–2012 suggest modest improvement. The recent 30+ years are characterized by high inter-annual variability of chl-a, coinciding with irregular dry and wet periods, complicating the detection of long-term trends. Here, we synthesize time-series data for historical and recent N loadings (TN, NO2 + NO3), chl-a, floral composition, and net primary productivity (NPP) to distinguish secular changes caused by nutrient over-enrichment from spatio-temporal variability imposed by climatic conditions. Wet years showed higher chl-a, higher diatom abundance, and increased NPP, while dry years showed lower chl-a, lower diatom abundance, and decreased NPP. Our findings support a conceptual model wherein variable climatic conditions dominate recent phytoplankton dynamics against a backdrop of nutrient over-enrichment, emphasizing the need to separate these effects to gauge progress toward improving water quality in estuaries.

  6. Impact of climate change on building structures

    Czech Academy of Sciences Publication Activity Database

    Drdácký, Miloš

    Bari : EDIPUGLIA, 2010 - (Lefebre, R.; Sabbioni, C.), s. 139-153 ISBN 978-88-7228-601-2 R&D Projects: GA ČR(CZ) GA103/09/2067 Grant ostatní: evropská komise(XE) 6th FP EC CHEF -044251 Institutional research plan: CEZ:AV0Z20710524 Keywords : climate change impact * weathering * vulnerability of buildings Subject RIV: AL - Art, Architecture, Cultural Heritage

  7. Expected impacts of climate change on extreme climate events; Impacts du changement climatique sur les evenements climatiques extremes

    Energy Technology Data Exchange (ETDEWEB)

    Planton, S.; Deque, M.; Chauvin, F. [Meteo-France, Centre National de Recherches Meteorologiques/groupe d' Etude de l' Atmosphere Meteorologique (CNRM/GAME), 31 - Toulouse (France); Terray, L. [Centre Europeen de Recherches Avancees en Calcul Scientifique, 31 - Toulouse (France)

    2008-09-15

    An overview of the expected change of climate extremes during this century due to greenhouse gases and aerosol anthropogenic emissions is presented. The most commonly used methodologies rely on the dynamical or statistical down-scaling of climate projections, performed with coupled atmosphere-ocean general circulation models. Either of dynamical or of statistical type, down-scaling methods present strengths and weaknesses, but neither their validation on present climate conditions, nor their potential ability to project the impact of climate change on extreme event statistics allows one to give a specific advantage to one of the two types. The results synthesized in the last IPCC report and more recent studies underline a convergence for a very likely increase in heat wave episodes over land surfaces, linked to the mean warming and the increase in temperature variability. In addition, the number of days of frost should decrease and the growing season length should increase. The projected increase in heavy precipitation events appears also as very likely over most areas and also seems linked to a change in the shape of the precipitation intensity distribution. The global trends for drought duration are less consistent between models and down-scaling methodologies, due to their regional variability. The change of wind-related extremes is also regionally dependent, and associated to a poleward displacement of the mid-latitude storm tracks. The specific study of extreme events over France reveals the high sensitivity of some statistics of climate extremes at the decadal time scale as a consequence of regional climate internal variability. (authors)

  8. Sensitivity of annual and seasonal reference crop evapotranspiration to principal climatic variables

    Indian Academy of Sciences (India)

    G T Patle; D K Singh

    2015-06-01

    Reference evapotranspiration (ET0) represents the evaporative demand of the atmosphere and depends on climatic parameters such as radiation, air temperature, humidity, and wind speed. Relative role of climatic parameter of ET0 varies from one climate to another and within the climate, and depends on the location and time. Sensitivity analysis was conducted and sensitivity coefficients were determined to evaluate the impact of principal climatic parameters on ET0 in Karnal district of India. Mean monthly ET0 and yearly ET0 from 1981 to 2011 were estimated from FAO-56 Penman–Monteith equation using the daily climate data collected from Central Soil Salinity Research Institute, Karnal. Results showed that seasonal and annual ET0 were most sensitive to maximum temperature followed by sunshine hours. However, wind speed, relative humidity, and minimum temperature had varying effect on mean ET0. After maximum temperature and sunshine hours, ET0 was more sensitive to wind speed followed by relative humidity and minimum temperature in summer. In monsoon, after maximum temperature and sunshine hours, ET0 was more sensitive to minimum temperature followed by relative humidity and wind speed. However, in winter, after maximum temperature and sunshine hours, ET0 was more sensitive to relative humidity followed by wind speed and minimum temperature. The study suggests that the climate variability would affect reference ET0; however, its impact on ET0 would be different for different parameters.

  9. Sensitivity of annual and seasonal reference crop evapotranspiration to principal climatic variables

    Science.gov (United States)

    Patle, G. T.; Singh, D. K.

    2015-06-01

    Reference evapotranspiration (ET0) represents the evaporative demand of the atmosphere and depends on climatic parameters such as radiation, air temperature, humidity, and wind speed. Relative role of climatic parameter of ET0 varies from one climate to another and within the climate, and depends on the location and time. Sensitivity analysis was conducted and sensitivity coefficients were determined to evaluate the impact of principal climatic parameters on ET0 in Karnal district of India. Mean monthly ET0 and yearly ET0 from 1981 to 2011 were estimated from FAO-56 Penman-Monteith equation using the daily climate data collected from Central Soil Salinity Research Institute, Karnal. Results showed that seasonal and annual ET0 were most sensitive to maximum temperature followed by sunshine hours. However, wind speed, relative humidity, and minimum temperature had varying effect on mean ET0. After maximum temperature and sunshine hours, ET0 was more sensitive to wind speed followed by relative humidity and minimum temperature in summer. In monsoon, after maximum temperature and sunshine hours, ET0 was more sensitive to minimum temperature followed by relative humidity and wind speed. However, in winter, after maximum temperature and sunshine hours, ET0 was more sensitive to relative humidity followed by wind speed and minimum temperature. The study suggests that the climate variability would affect reference ET0; however, its impact on ET0 would be different for different parameters.

  10. ENSO Variability at Vanuatu during the Medieval Climate Anomaly

    Science.gov (United States)

    Hereid, K. A.; Quinn, T. M.; Taylor, F. W.; Edwards, R.; Cheng, H.; Shen, C.

    2011-12-01

    The Medieval Climate Anomaly (MCA; ~1050 - 1250 CE) is a period of warm temperatures in the Northern Hemisphere high latitudes caused by enhanced solar forcing. The tropical response to this forcing is variable; sediment records from the tropical Pacific indicate warm conditions in the western tropics and cooler temperatures in the east during this interval, paired with precipitation changes that suggest a northward migration of the Intertropical Convergence Zone. Speleothem records and western Pacific sediment cores match this migration with a strengthened Asian monsoon, indicating a substantial reorganization in hydrology. However, the effect of these changes in zonal and meridional circulation patterns on the El Niño-Southern Oscillation (ENSO), the dominant mode of global interannual climate variability, is unclear. Conflicting hypotheses arise due to datasets that are too short to be representative of multidecadal ENSO variability trends, cannot identify individual ENSO events due to lower than annual resolution, or are located in remote, teleconnected regions. We present a suite of monthly resolved geochemical records from fossil Porites corals at Vanuatu (Tasmaloum, Espiritu Santo), a location whose climate is strongly influenced by variations in ENSO and the South Pacific Convergence Zone (SPCZ). Our proxy coral records of sea surface temperature (SST) and sea surface salinity (SSS) variations provide multidecadal- to centennial-scale windows into ENSO variability and mean climate state from ~600 - 1250 CE in the deep tropics. Preliminary results, based on coral Sr/Ca variations during a portion of the MCA, suggest that SST was cooler than modern at Vanuatu, with similar levels of total variability. Additional data acquisition and future work will focus on assessing potential ENSO event frequency and magnitude changes during the MCA in the deep tropics.

  11. Northern hemisphere winter atmospheric climate: modes of natural variability and climate change

    Science.gov (United States)

    Keeley, Sarah P. E.; Collins, Matthew; Thorpe, Alan J.

    2008-08-01

    Under anthropogenic climate change it is possible that the increased radiative forcing and associated changes in mean climate may affect the “dynamical equilibrium” of the climate system; leading to a change in the relative dominance of different modes of natural variability, the characteristics of their patterns or their behavior in the time domain. Here we use multi-century integrations of version three of the Hadley Centre atmosphere model coupled to a mixed layer ocean to examine potential changes in atmosphere-surface ocean modes of variability. After first evaluating the simulated modes of Northern Hemisphere winter surface temperature and geopotential height against observations, we examine their behavior under an idealized equilibrium doubling of atmospheric CO2. We find no significant changes in the order of dominance, the spatial patterns or the associated time series of the modes. Having established that the dynamic equilibrium is preserved in the model on doubling of CO2, we go on to examine the temperature pattern of mean climate change in terms of the modes of variability; the motivation being that the pattern of change might be explicable in terms of changes in the amount of time the system resides in a particular mode. In addition, if the two are closely related, we might be able to assess the relative credibility of different spatial patterns of climate change from different models (or model versions) by assessing their representation of variability. Significant shifts do appear to occur in the mean position of residence when examining a truncated set of the leading order modes. However, on examining the complete spectrum of modes, it is found that the mean climate change pattern is close to orthogonal to all of the modes and the large shifts are a manifestation of this orthogonality. The results suggest that care should be exercised in using a truncated set of variability EOFs to evaluate climate change signals.

  12. Climate Change Impacts in a Colombian Andean Tropical Basin

    Science.gov (United States)

    Ocampo, O. L.; Vélez, J. J.; Londoño, A.

    2012-12-01

    Climate change and climate variability have a large impact on water resources. Developing regions have less capacity to prepare for, respond to, and recover from climate-related hazards and effects, and then, populations may be disproportionately affected. In Colombia, the geographical location and the marked irregularity in the terrain, give as a result, a complex climate. These factors have contributed to the water supply of the territory. Unfortunately, the visualization of abundant and inexhaustible water resources created a great disregard for them. Besides, the water supply is not distributed uniformly across the country, and then there is water-deficit in some areas as Andean Region, where the largest population and the main development centers are located. In recent decades, water conflicts have emerged locally and regionally, which have generated a crisis in the allocation mechanisms and have improved the understanding of the water situation in Colombia. The Second National Communication to CCMNU alerts on possible future consequences of climate change and the need for regional studies for understanding climate change impacts on the fragile ecosystems of high mountains as paramos and fog forest, which are water production regulators. Colombian water resources are greatly affected by changes in rainfall patterns influenced by El Niño and La Niña. The recent disasters in the 2010-2011 rainy seasons have caught the attention of not only the authorities but from the scientific community to explore strategies to improve water management by tracking, anticipating and responding to climate variability and climate change. Whereas sound water management is built upon long-term, the country is undertaking a pilot exercise for the integrated management of water resources, five Basins are selected, among them, is the Chinchiná River Basin; this Andean tropical Basin is located on the western slopes at the central range in the Andes between 4°48 and 5°12 N

  13. Shift of biome patterns due to simulated climate variability and climate change

    International Nuclear Information System (INIS)

    The variability of simulated equilibrium-response patterns of biomes caused by simulated climate variability and climate shift is analysed. This investigation is based on various realisations of simulated present-day climate and climate shift. It has been found that the difference between biomes computed from three 10-year climatologies and from the corresponding 30-year climatology, simulated by the Hamburg climate model at T21 resolution, amounts to approximately 6% of the total land area, Antarctica excluded. This difference is mainly due to differences in annual moisture availability and winter temperatures. When intercomparing biomes from the 10-year climatologies a 10% difference is seen, but there is no unique difference pattern. In contrast to the interdecadal variability, the shift of conditions favorable for biomes due to a shift in climate in the next 100 years, caused by an increase in sea-surface temperatures and atmospheric CO2, reveals a unique trend pattern. It turns out that the strongest and most significant signal is the north-east shift of conditions for boreal biomes. This signal is caused by an increase of annual temperature sums as well as mean temperatures of the coldest and warmest months. Trends in annual moisture availability are of secondary importance globally. Regionally, a decrease in water availability affects biomes in Central and East Europe and an increase of water availability leads to a potential increase in tropical rain forest. In total, all differences amount to roughly 30% of the total land surface, Antarctica excluded. (orig./KW)

  14. A simulation of the economic and environmental impact of variable rate nitrogen application

    DEFF Research Database (Denmark)

    Pedersen, Søren Marcus; Pedersen, Jørgen Lindgaard

    2003-01-01

    the field. However, findings from this also indicate that changing climatic conditions have a significant impact on yield response from variable nitrogen application. The study also establishes that site-specific N-application seems to have a positive but also small impact on nitrate leaching in...

  15. Population variability complicates the accurate detection of climate change responses.

    Science.gov (United States)

    McCain, Christy; Szewczyk, Tim; Bracy Knight, Kevin

    2016-06-01

    The rush to assess species' responses to anthropogenic climate change (CC) has underestimated the importance of interannual population variability (PV). Researchers assume sampling rigor alone will lead to an accurate detection of response regardless of the underlying population fluctuations of the species under consideration. Using population simulations across a realistic, empirically based gradient in PV, we show that moderate to high PV can lead to opposite and biased conclusions about CC responses. Between pre- and post-CC sampling bouts of modeled populations as in resurvey studies, there is: (i) A 50% probability of erroneously detecting the opposite trend in population abundance change and nearly zero probability of detecting no change. (ii) Across multiple years of sampling, it is nearly impossible to accurately detect any directional shift in population sizes with even moderate PV. (iii) There is up to 50% probability of detecting a population extirpation when the species is present, but in very low natural abundances. (iv) Under scenarios of moderate to high PV across a species' range or at the range edges, there is a bias toward erroneous detection of range shifts or contractions. Essentially, the frequency and magnitude of population peaks and troughs greatly impact the accuracy of our CC response measurements. Species with moderate to high PV (many small vertebrates, invertebrates, and annual plants) may be inaccurate 'canaries in the coal mine' for CC without pertinent demographic analyses and additional repeat sampling. Variation in PV may explain some idiosyncrasies in CC responses detected so far and urgently needs more careful consideration in design and analysis of CC responses. PMID:26725404

  16. The Impact of Climate Change on Tourism in Spain

    OpenAIRE

    Hein, Lars

    2007-01-01

    The tourism sector will be particularly affected by climate change, but there have been few studies specifying the impacts of climate change on tourism for a certain country. This paper considers the impacts of climate change on tourism in Spain. Tourism is a key economic sector in Spain, and it is strongly weather dependent. The paper analyses how the suitability of the Spanish climate for tourism will change, and how this will affect tourism flows to Spain. The suitability of the climate fo...

  17. Climate change impacts on the temperature of recharge water in a temporate climate

    Science.gov (United States)

    Murdock, E. A.

    2015-12-01

    Groundwater outflows into headwater streams play an important role in controlling local stream temperature and maintaining habitat for cool and cold water fisheries. Because of the ecological and economic importance of these fisheries, there is significant concern about the impacts of climate change on these habitats. Many studies of stream temperature changes under climate change assume that groundwater outflows will vary with long-term mean air temperature, perhaps with a temporal lag to account for the relatively slow rate of heat diffusion through soils. This assumption, however, ignores the fact that climate change will also impact the temporal patterns of recharge in some regions. In Southern Wisconsin, much of the annual recharge comes from the spring snowmelt event, as a large amount of meltwater is released onto saturated soils with little to no active transpiration. Using the Simultaneous Heat and Water (SHAW) model populated with climate date from the North American Regional Climate Change Assessment Program (NARCCAP), we show that the temperature of water passing below the rooting zone in a simulated corn planting in Southern Wisconsin will change significantly less than the air temperature by midcentury. This finding highlights the importance of understanding the variability of heat flow mechanisms in the subsurface while assessing climate change impacts on surface water resources. In landscapes such as Wisconsin's driftless area, where deep aquifers feed numerous localized headwater streams, meltwater-driven recharge may provide a buffer against rising air temperatures for some time into the future. Fully understanding this dynamic will allow for targeted conservation efforts in those streams that are likely to show higher than average resilience to rising temperatures, but which remain vulnerable to development, stormwater runoff, agricultural pollution and other ecological threats. In a world with dwindling coldwater resources, identifying and

  18. Evidence of multidecadal climate variability in the Gulf of Mexico

    Science.gov (United States)

    Poore, Richard Z.; Brock, John C.

    2011-01-01

    The northern Gulf of Mexico coastal region is vulnerable to a variety of natural hazards, many of which are linked to climate and climate variability. Hurricanes, which are one such climate-related hazard, are a major recurring problem, and the active hurricane seasons of 2004 and 2005 raised interest in better understanding the controls and risks of hurricanes. Examination of historical records reveals intervals of alternating low and high hurricane activity that appear to be related to changes in average sea-surface temperature in the North Atlantic Ocean. Analyses of instrumental temperature records from the North Atlantic show decadal-scale oscillations of slightly higher versus slightly lower average temperature extending back in time for over 100 years. This oscillation is known as the Atlantic Multidecadal Oscillation (AMO).

  19. Rainfall variability and extremes over southern Africa: Assessment of a climate model to reproduce daily extremes

    Science.gov (United States)

    Williams, C. J. R.; Kniveton, D. R.; Layberry, R.

    2009-04-01

    It is increasingly accepted that that any possible climate change will not only have an influence on mean climate but may also significantly alter climatic variability. A change in the distribution and magnitude of extreme rainfall events (associated with changing variability), such as droughts or flooding, may have a far greater impact on human and natural systems than a changing mean. This issue is of particular importance for environmentally vulnerable regions such as southern Africa. The subcontinent is considered especially vulnerable to and ill-equipped (in terms of adaptation) for extreme events, due to a number of factors including extensive poverty, famine, disease and political instability. Rainfall variability and the identification of rainfall extremes is a function of scale, so high spatial and temporal resolution data are preferred to identify extreme events and accurately predict future variability. The majority of previous climate model verification studies have compared model output with observational data at monthly timescales. In this research, the assessment of ability of a state of the art climate model to simulate climate at daily timescales is carried out using satellite derived rainfall data from the Microwave Infra-Red Algorithm (MIRA). This dataset covers the period from 1993-2002 and the whole of southern Africa at a spatial resolution of 0.1 degree longitude/latitude. The ability of a climate model to simulate current climate provides some indication of how much confidence can be applied to its future predictions. In this paper, simulations of current climate from the UK Meteorological Office Hadley Centre's climate model, in both regional and global mode, are firstly compared to the MIRA dataset at daily timescales. This concentrates primarily on the ability of the model to simulate the spatial and temporal patterns of rainfall variability over southern Africa. Secondly, the ability of the model to reproduce daily rainfall extremes will

  20. Tropical cloud feedbacks and natural variability of climate

    Science.gov (United States)

    Miller, R. L.; Del Genio, A. D.

    1994-01-01

    Simulations of natural variability by two general circulation models (GCMs) are examined. One GCM is a sector model, allowing relatively rapid integration without simplification of the model physics, which would potentially exclude mechanisms of variability. Two mechanisms are found in which tropical surface temperature and sea surface temperature (SST) vary on interannual and longer timescales. Both are related to changes in cloud cover that modulate SST through the surface radiative flux. Over the equatorial ocean, SST and surface temperature vary on an interannual timescale, which is determined by the magnitude of the associated cloud cover anomalies. Over the subtropical ocean, variations in low cloud cover drive SST variations. In the sector model, the variability has no preferred timescale, but instead is characterized by a 'red' spectrum with increasing power at longer periods. In the terrestrial GCM, SST variability associated with low cloud anomalies has a decadal timescale and is the dominant form of global temperature variability. Both GCMs are coupled to a mixed layer ocean model, where dynamical heat transports are prescribed, thus filtering out El Nino-Southern Oscillation (ENSO) and thermohaline circulation variability. The occurrence of variability in the absence of dynamical ocean feedbacks suggests that climatic variability on long timescales can arise from atmospheric processes alone.

  1. Predicting Climate Change Impacts to the Canadian Boreal Forest

    Directory of Open Access Journals (Sweden)

    Trisalyn A. Nelson

    2014-03-01

    Full Text Available Climate change is expected to alter temperature, precipitation, and seasonality with potentially acute impacts on Canada’s boreal. In this research we predicted future spatial distributions of biodiversity in Canada’s boreal for 2020, 2050, and 2080 using indirect indicators derived from remote sensing and based on vegetation productivity. Vegetation productivity indices, representing annual amounts and variability of greenness, have been shown to relate to tree and wildlife richness in Canada’s boreal. Relationships between historical satellite-derived productivity and climate data were applied to modelled scenarios of future climate to predict and map potential future vegetation productivity for 592 regions across Canada. Results indicated that the pattern of vegetation productivity will become more homogenous, particularly west of Hudson Bay. We expect climate change to impact biodiversity along north/south gradients and by 2080 vegetation distributions will be dominated by processes of seasonality in the north and a combination of cumulative greenness and minimum cover in the south. The Hudson Plains, which host the world’s largest and most contiguous wetland, are predicted to experience less seasonality and more greenness. The spatial distribution of predicted trends in vegetation productivity was emphasized over absolute values, in order to support regional biodiversity assessments and conservation planning.

  2. Sensitivity of water scarcity events to ENSO-driven climate variability at the global scale

    Science.gov (United States)

    Veldkamp, T. I. E.; Eisner, S.; Wada, Y.; Aerts, J. C. J. H.; Ward, P. J.

    2015-10-01

    Globally, freshwater shortage is one of the most dangerous risks for society. Changing hydro-climatic and socioeconomic conditions have aggravated water scarcity over the past decades. A wide range of studies show that water scarcity will intensify in the future, as a result of both increased consumptive water use and, in some regions, climate change. Although it is well-known that El Niño-Southern Oscillation (ENSO) affects patterns of precipitation and drought at global and regional scales, little attention has yet been paid to the impacts of climate variability on water scarcity conditions, despite its importance for adaptation planning. Therefore, we present the first global-scale sensitivity assessment of water scarcity to ENSO, the most dominant signal of climate variability. We show that over the time period 1961-2010, both water availability and water scarcity conditions are significantly correlated with ENSO-driven climate variability over a large proportion of the global land area (> 28.1 %); an area inhabited by more than 31.4 % of the global population. We also found, however, that climate variability alone is often not enough to trigger the actual incidence of water scarcity events. The sensitivity of a region to water scarcity events, expressed in terms of land area or population exposed, is determined by both hydro-climatic and socioeconomic conditions. Currently, the population actually impacted by water scarcity events consists of 39.6 % (CTA: consumption-to-availability ratio) and 41.1 % (WCI: water crowding index) of the global population, whilst only 11.4 % (CTA) and 15.9 % (WCI) of the global population is at the same time living in areas sensitive to ENSO-driven climate variability. These results are contrasted, however, by differences in growth rates found under changing socioeconomic conditions, which are relatively high in regions exposed to water scarcity events. Given the correlations found between ENSO and water availability and

  3. Sensitivity of Water Scarcity Events to ENSO-Driven Climate Variability at the Global Scale

    Science.gov (United States)

    Veldkamp, T. I. E.; Eisner, S.; Wada, Y.; Aerts, J. C. J. H.; Ward, P. J.

    2015-01-01

    Globally, freshwater shortage is one of the most dangerous risks for society. Changing hydro-climatic and socioeconomic conditions have aggravated water scarcity over the past decades. A wide range of studies show that water scarcity will intensify in the future, as a result of both increased consumptive water use and, in some regions, climate change. Although it is well-known that El Niño- Southern Oscillation (ENSO) affects patterns of precipitation and drought at global and regional scales, little attention has yet been paid to the impacts of climate variability on water scarcity conditions, despite its importance for adaptation planning. Therefore, we present the first global-scale sensitivity assessment of water scarcity to ENSO, the most dominant signal of climate variability. We show that over the time period 1961-2010, both water availability and water scarcity conditions are significantly correlated with ENSO-driven climate variability over a large proportion of the global land area (> 28.1 %); an area inhabited by more than 31.4% of the global population. We also found, however, that climate variability alone is often not enough to trigger the actual incidence of water scarcity events. The sensitivity of a region to water scarcity events, expressed in terms of land area or population exposed, is determined by both hydro-climatic and socioeconomic conditions. Currently, the population actually impacted by water scarcity events consists of 39.6% (CTA: consumption-to-availability ratio) and 41.1% (WCI: water crowding index) of the global population, whilst only 11.4% (CTA) and 15.9% (WCI) of the global population is at the same time living in areas sensitive to ENSO-driven climate variability. These results are contrasted, however, by differences in growth rates found under changing socioeconomic conditions, which are relatively high in regions exposed to water scarcity events. Given the correlations found between ENSO and water availability and scarcity

  4. Integrated Climate Change Impacts Assessment in California

    Science.gov (United States)

    Cayan, D. R.; Franco, G.; Meyer, R.; Anderson, M.; Bromirski, P. D.

    2014-12-01

    This paper summarizes lessons learned from an ongoing series of climate change assessments for California, conducted by the scientific community and State and local agencies. A series of three Assessments have considered vulnerability and adaptation issues for both managed and natural systems. California's vulnerability is many faceted, arising because of an exceptionally drought prone climate, open coast and large estuary exposure to sea level rise, sensitive ecosystems and complex human footprint and economy. Key elements of the assessments have been a common set of climate and sea-level rise scenarios, based upon IPCC GCM simulations. Regionalized and localized output from GCM projections was provided to research teams investigating water supply, agriculture, coastal resources, ecosystem services, forestry, public health, and energy demand and hydropower generation. The assessment results are helping to investigate the broad range of uncertainty that is inherent in climate projections, and users are becoming better equipped to process an envelope of potential climate and impacts. Some projections suggest that without changes in California's present fresh-water delivery system, serious water shortages would take place, but that technical solutions are possible. Under a warmer climate, wildfire vulnerability is heightened markedly in some areas--estimated increases in burned area by the end of the 21st Century exceed 100% of the historical area burned in much of the forested areas of Northern California Along California coast and estuaries, projected rise in mean sea level will accelerate flooding occurrences, prompting the need for better education and preparedness. Many policymakers and agency personnel in California are factoring in results from the assessments and recognize the need for a sustained assessment process. An ongoing challenge, of course, is to achieve more engagement with a broader community of decision makers, and notably with the private sector.

  5. Influence of solar and cosmic-ray variability on climate

    CERN Document Server

    Badruddin,; Singh, M

    2013-01-01

    We analyze solar, geomagnetic and cosmic ray flux data along with rainfall and temperature data for almost five solar cycles. We provide evidence of significant influence of solar variability on climate. Specifically, we demonstrate association between lower (higher) rainfall and higher (lower) temperatures with increasing (decreasing) solar activity and decreasing (increasing) cosmic ray intensities. We propose a plausible scenario that accounts the results of our analysis.

  6. Monofractal nature of air temperature signals reveals their climate variability

    CERN Document Server

    Deliège, Adrien

    2014-01-01

    We use the discrete "wavelet transform microscope" to show that the surface air temperature signals of weather stations selected in Europe are monofractal. This study reveals that the information obtained in this way are richer than previous works studying long range correlations in meteorological stations. The approach presented here allows to bind the H\\"older exponents with the climate variability. We also establish that such a link does not exist with methods previously carried out.

  7. Climate change and its impacts on crop production: A case study in Khotang district of Nepal

    OpenAIRE

    Dhakal, Kabindra

    2014-01-01

    This research was carried out to study climate change and its impacts on major crops production in Khotang district of Nepal. The effect of climate variables on crops yield and farmers` respond to climate change in the last eight to ten years were studied and analyzed. Monthly precipitation data in Aiselukharka, Kuruleghat, Khotangbajar and Diktel; and monthly minimum and maximum air temperatures data in Okhaldhunga, Chainpur East and Udayapur Gadhi available from the Department of Hydrology ...

  8. Impacts of Climate Change on Public Health in India: Future Research Directions

    OpenAIRE

    Bush, Kathleen F.; Luber, George; Kotha, S Rani; R. S. Dhaliwal; Kapil, Vikas; Pascual, Mercedes; Brown, Daniel G.; Frumkin, Howard; R.C. Dhiman; Hess, Jeremy; Wilson, Mark L; Balakrishnan, Kalpana; Eisenberg, Joseph; Kaur, Tanvir; Rood, Richard

    2011-01-01

    Background Climate change and associated increases in climate variability will likely further exacerbate global health disparities. More research is needed, particularly in developing countries, to accurately predict the anticipated impacts and inform effective interventions. Objectives Building on the information presented at the 2009 Joint Indo–U.S. Workshop on Climate Change and Health in Goa, India, we reviewed relevant literature and data, addressed gaps in knowledge, and identified prio...

  9. A Europe-South America network for climate change assessment and impact studies

    OpenAIRE

    Boulanger, Jean-Philippe; Brasseur, G.; Carril, A. F.; M. Castro; Dégallier, Nicolas; Ereno, C.; Le Treut, H.; Marengo, J.A.; Menendez, C. G.; Nunez, M. N.; Penalba, O. C.; Rolla, A. L.; Rusticucci, M.; R. Terra

    2010-01-01

    The goal of the CLARIS project was to build an integrated European-South American network dedicated to promote common research strategies to observe and predict climate changes and their consequent socio-economic impacts taking into account the climate and societal peculiarities of South America. Reaching that goal placed the present network as a privileged advisor to contribute to the design of adaptation strategies in a region strongly affected by and dependent on climate variability (e. g....

  10. Climate Change Impacts on Water Supply and Demand in Rheraya Watershed (Morocco), with Potential Adaptation Strategies

    OpenAIRE

    Rochdane, Saloua; Reichert, Barbara; Messouli, Mohammed; Babqiqi, Abdelaziz; Khebiza, Mohammed Yacoubi

    2012-01-01

    Rheraya watershed already suffers from the impacts of climate variability and will be further affected by climate change. Severe water shortages and extremely fragile ecological conditions necessitate careful attention to water resources management. The aim of this study is to analyze Rheraya’s future water situation under different scenarios of socio-economic development and climate change until 2100. The Water Evaluation and Planning System model (WEAP) has been applied to estimate the curr...

  11. Sustainability analysis of bioenergy based land use change under climate change and variability

    Science.gov (United States)

    Raj, C.; Chaubey, I.; Brouder, S. M.; Bowling, L. C.; Cherkauer, K. A.; Frankenberger, J.; Goforth, R. R.; Gramig, B. M.; Volenec, J. J.

    2014-12-01

    Sustainability analyses of futuristic plausible land use and climate change scenarios are critical in making watershed-scale decisions for simultaneous improvement of food, energy and water management. Bioenergy production targets for the US are anticipated to impact farming practices through the introduction of fast growing and high yielding perennial grasses/trees, and use of crop residues as bioenergy feedstocks. These land use/land management changes raise concern over potential environmental impacts of bioenergy crop production scenarios, both in terms of water availability and water quality; impacts that may be exacerbated by climate variability and change. The objective of the study was to assess environmental, economic and biodiversity sustainability of plausible bioenergy scenarios for two watersheds in Midwest US under changing climate scenarios. The study considers fourteen sustainability indicators under nine climate change scenarios from World Climate Research Programme's (WCRP's) Coupled Model Intercomparison Project phase 3 (CMIP3). The distributed hydrological model SWAT (Soil and Water Assessment Tool) was used to simulate perennial bioenergy crops such as Miscanthus and switchgrass, and corn stover removal at various removal rates and their impacts on hydrology and water quality. Species Distribution Models (SDMs) developed to evaluate stream fish response to hydrology and water quality changes associated with land use change were used to quantify biodiversity sustainability of various bioenergy scenarios. The watershed-scale sustainability analysis was done in the St. Joseph River watershed located in Indiana, Michigan, and Ohio; and the Wildcat Creek watershed, located in Indiana. The results indicate streamflow reduction at watershed outlet with increased evapotranspiration demands for high-yielding perennial grasses. Bioenergy crops in general improved in-stream water quality compared to conventional cropping systems (maize-soybean). Water

  12. Towards multi-resolution global climate modeling with ECHAM6-FESOM. Part II: climate variability

    Science.gov (United States)

    Rackow, T.; Goessling, H. F.; Jung, T.; Sidorenko, D.; Semmler, T.; Barbi, D.; Handorf, D.

    2016-06-01

    This study forms part II of two papers describing ECHAM6-FESOM, a newly established global climate model with a unique multi-resolution sea ice-ocean component. While part I deals with the model description and the mean climate state, here we examine the internal climate variability of the model under constant present-day (1990) conditions. We (1) assess the internal variations in the model in terms of objective variability performance indices, (2) analyze variations in global mean surface temperature and put them in context to variations in the observed record, with particular emphasis on the recent warming slowdown, (3) analyze and validate the most common atmospheric and oceanic variability patterns, (4) diagnose the potential predictability of various climate indices, and (5) put the multi-resolution approach to the test by comparing two setups that differ only in oceanic resolution in the equatorial belt, where one ocean mesh keeps the coarse ~1° resolution applied in the adjacent open-ocean regions and the other mesh is gradually refined to ~0.25°. Objective variability performance indices show that, in the considered setups, ECHAM6-FESOM performs overall favourably compared to five well-established climate models. Internal variations of the global mean surface temperature in the model are consistent with observed fluctuations and suggest that the recent warming slowdown can be explained as a once-in-one-hundred-years event caused by internal climate variability; periods of strong cooling in the model (`hiatus' analogs) are mainly associated with ENSO-related variability and to a lesser degree also to PDO shifts, with the AMO playing a minor role. Common atmospheric and oceanic variability patterns are simulated largely consistent with their real counterparts. Typical deficits also found in other models at similar resolutions remain, in particular too weak non-seasonal variability of SSTs over large parts of the ocean and episodic periods of almost absent

  13. The climate4impact portal: bridging the CMIP5 data infrastructure to impact users

    Science.gov (United States)

    Plieger, Maarten; Som de Cerff, Wim; Page, Christian; Hutjes, Ronald; de Jong, Fokke; Bärring, Lars; Sjökvist, Elin

    2013-04-01

    conjunction with several external websites and systems. The climate4impact portal uses X509 based short lived credentials, generated on behalf of the user with a MyProxy service. Single Sign-on (SSO) is used to make these websites and systems work together. - Discovery: Facetted search based on e.g. variable name, model and institute using the ESG search services. A catalog browser allows for browsing through CMIP5 and other climate model data catalogues (e.g. ESSENCE, EOBS, UNIDATA). - Download: Directly from ESG nodes and other THREDDS catalogs - Visualization: Visualize any data directly using ADAGUC dynamic Web Map Services. - Transformation: Transform your data into other formats, perform basic calculations and extractions using OCG Web Processing Services The current portal is a Prototype. It is built to explore state-of-art technologies to provide improved access to climate model data. The prototype will be evaluated and is the basis for development of an operational service. The portal and services provided will be sustained and supported during the development of these operational services (2013-2016) in the second phase of the FP7 IS-ENES project, ISENES2.

  14. Impacts of climate change on water resources in southern Africa: A review

    Science.gov (United States)

    Kusangaya, Samuel; Warburton, Michele L.; Archer van Garderen, Emma; Jewitt, Graham P. W.

    The Intergovernmental Panel on Climate Change concluded that there is consensus that the increase of atmospheric greenhouse gases will result in climate change which will cause the sea level to rise, increased frequency of extreme climatic events including intense storms, heavy rainfall events and droughts. This will increase the frequency of climate-related hazards, causing loss of life, social disruption and economic hardships. There is less consensus on the magnitude of change of climatic variables, but several studies have shown that climate change will impact on the availability and demand for water resources. In southern Africa, climate change is likely to affect nearly every aspect of human well-being, from agricultural productivity and energy use to flood control, municipal and industrial water supply to wildlife management, since the region is characterised by highly spatial and temporally variable rainfall and, in some cases, scarce water resources. Vulnerability is exacerbated by the region's low adaptive capacity, widespread poverty and low technology uptake. This paper reviews the potential impacts of climate change on water resources in southern Africa. The outcomes of this review include highlighting studies on detected climate changes particularly focusing on temperature and rainfall. Additionally, the impacts of climate change are highlighted, and respective studies on hydrological responses to climate change are examined. The review also discusses the challenges in climate change impact analysis, which inevitably represents existing research and knowledge gaps. Finally the paper concludes by outlining possible research areas in the realm of climate change impacts on water resources, particularly knowledge gaps in uncertainty analysis for both climate change and hydrological modelling.

  15. Characterizing climate predictability and model response variability from multiple initial condition and multi-model ensembles

    CERN Document Server

    Kumar, Devashish

    2016-01-01

    Climate models are thought to solve boundary value problems unlike numerical weather prediction, which is an initial value problem. However, climate internal variability (CIV) is thought to be relatively important at near-term (0-30 year) prediction horizons, especially at higher resolutions. The recent availability of significant numbers of multi-model (MME) and multi-initial condition (MICE) ensembles allows for the first time a direct sensitivity analysis of CIV versus model response variability (MRV). Understanding the relative agreement and variability of MME and MICE ensembles for multiple regions, resolutions, and projection horizons is critical for focusing model improvements, diagnostics, and prognosis, as well as impacts, adaptation, and vulnerability studies. Here we find that CIV (MICE agreement) is lower (higher) than MRV (MME agreement) across all spatial resolutions and projection time horizons for both temperature and precipitation. However, CIV dominates MRV over higher latitudes generally an...

  16. Contribution of geodiversity, climate and spatial variables for biodiversity across a gradient of human influence

    Science.gov (United States)

    Tukiainen, Helena; Alahuhta, Janne; Ala-Hulkko, Terhi; Field, Richard; Lampinen, Raino; Hjort, Jan

    2016-04-01

    Implementation of geodiversity may provide new perspectives for nature conservation. The relation between geodiversity and biodiversity has been established in recent studies but remains underexplored in environments with high human pressure. In this study, we explored the effect of geodiversity (i.e. geological, hydrological and geomorphological diversity), climate and spatial variables on biodiversity (vascular plant species richness) in environments with different human impact. The study area ranged trough the boreal vegetation zone in Finland and included altogether 1401 1-km2 grid cells from urban, rural and natural environments. The contribution of environmental variable groups for species diversity in different environments was statistically analyzed with variation partitioning method. According to the results, the contribution of geodiversity decreased and the contribution of climate and spatial variables increased as the land use became more human-induced. Hence, the connection between geodiversity and species richness was most pronounced in natural state environments.

  17. An Integrated Hydro-Economic Model for Economy-Wide Climate Change Impact Assessment for Zambia

    Science.gov (United States)

    Zhu, T.; Thurlow, J.; Diao, X.

    2008-12-01

    Zambia is a landlocked country in Southern Africa, with a total population of about 11 million and a total area of about 752 thousand square kilometers. Agriculture in the country depends heavily on rainfall as the majority of cultivated land is rain-fed. Significant rainfall variability has been a huge challenge for the country to keep a sustainable agricultural growth, which is an important condition for the country to meet the United Nations Millennium Development Goals. The situation is expected to become even more complex as climate change would impose additional impacts on rainwater availability and crop water requirements, among other changes. To understand the impacts of climate variability and change on agricultural production and national economy, a soil hydrology model and a crop water production model are developed to simulate actual crop water uses and yield losses under water stress which provide annual shocks for a recursive dynamic computational general equilibrium (CGE) model developed for Zambia. Observed meteorological data of the past three decades are used in the integrated hydro-economic model for climate variability impact analysis, and as baseline climatology for climate change impact assessment together with several GCM-based climate change scenarios that cover a broad range of climate projections. We found that climate variability can explain a significant portion of the annual variations of agricultural production and GDP of Zambia in the past. Hidden beneath climate variability, climate change is found to have modest impacts on agriculture and national economy of Zambia around 2025 but the impacts would be pronounced in the far future if appropriate adaptations are not implemented. Policy recommendations are provided based on scenario analysis.

  18. The Climate Variability & Predictability (CVP) Program at NOAA - DYNAMO Recent Project Advancements

    Science.gov (United States)

    Lucas, S. E.; Todd, J. F.; Higgins, W.

    2013-12-01

    The Climate Variability & Predictability (CVP) Program supports research aimed at providing process-level understanding of the climate system through observation, modeling, analysis, and field studies. This vital knowledge is needed to improve climate models and predictions so that scientists can better anticipate the impacts of future climate variability and change. To achieve its mission, the CVP Program supports research carried out at NOAA and other federal laboratories, NOAA Cooperative Institutes, and academic institutions. The Program also coordinates its sponsored projects with major national and international scientific bodies including the World Climate Research Programme (WCRP), the International Geosphere-Biosphere Programme (IGBP), and the U.S. Global Change Research Program (USGCRP). The CVP program sits within the Earth System Science (ESS) Division at NOAA's Climate Program Office. Dynamics of the Madden-Julian Oscillation (DYNAMO): The Indian Ocean is one of Earth's most sensitive regions because the interactions between ocean and atmosphere there have a discernable effect on global climate patterns. The tropical weather that brews in that region can move eastward along the equator and reverberate around the globe, shaping weather and climate in far-off places. The vehicle for this variability is a phenomenon called the Madden-Julian Oscillation, or MJO. The MJO, which originates over the Indian Ocean roughly every 30 to 90 days, is known to influence the Asian and Australian monsoons. It can also enhance hurricane activity in the northeast Pacific and Gulf of Mexico, trigger torrential rainfall along the west coast of North America, and affect the onset of El Niño. CVP-funded scientists participated in the DYNAMO field campaign in 2011-12. Results from this international campaign are expected to improve researcher's insights into this influential phenomenon. A better understanding of the processes governing MJO is an essential step toward

  19. Climate Variability, Andean Livelihood Strategies, Development and Adaptation in the Andean Region

    Science.gov (United States)

    Valdivia, C.; Quiroz, R.; Zorogastua, P.; Baigorrea, G.

    2002-05-01

    Development programs in the Andes have failed to recognize climate variability as an element that is crucial to the adoption of new alternatives. Dairy, potatoes, improved sheep, forages are all part of the history of development in this region. A combination of climate variability, changes in the economy, the political environment, and land tenure reform shape rural livelihoods and welfare. Diversification, linking to markets, and networking are some elements that contribute to the resilience of families in the Andes. Strategies change, are flexible, and may incorporate non-agricultural activities. While some farmers are able to improve their welfare through the life cycle, others become poorer. Climate variability increases the vulnerability of some groups; in other cases, because of diversification and assets, households build economic portfolios that are more resilient to the elements. The many projects provide insights into how in the long run households improve their environment, hinting at mechanisms to adapt to climate change. In order to understand changing composition of portfolios in future scenarios of spatial heterogeneous areas such as mountains (Andes), estimates of models predicting climate change at a global scale are not useful because their resolution. Therefore, downscaling tools are useful. Spatial heterogeneity is assessed through agroecozoning. Both production and the impact on some environmental indicators are simulated through process-based models, for the Ilave-Huenque watershed in Peru that help in discussing scenarios of adaptation.

  20. Making the best of climatic variability: options for upgrading rainfed farming in water scarce regions.

    Science.gov (United States)

    Rockström, J

    2004-01-01

    Coping with climatic variability for livelihood security is part of everyday life for rural communities in semi-arid and dry sub-humid savannas. Water scarcity caused by rainfall fluctuations is common, causing meteorological droughts and dry spells. However, this paper indicates, based on experiences in sub-Saharan Africa and India, that the social impact on rural societies of climatically induced droughts is exaggerated. Instead, water scarcity causing food deficits is more often caused by management induced droughts and dry spells. A conceptual framework to distinguish between manageable and unmanageable droughts is presented. It is suggested that climatic droughts require focus on social resilience building instead of land and water resource management. Focus is then set on the manageable part of climatic variability, namely the almost annual occurrence of dry spells, short 2-4 week periods of no rainfall, affecting farmer yields. On-farm experiences in savannas of sub-Saharan Africa of water harvesting systems for dry spell mitigation are presented. It is shown that bridging dry spells combined with soil fertility management can double and even triple on-farm yield levels. Combined with innovative systems to ensure maximum plant water availability and water uptake capacity, through adoption of soil fertility improvement and conservation tillage systems, there is a clear opportunity to upgrade rainfed farming systems in vulnerable savanna environments, through appropriate local management of climatic variability. PMID:15195432

  1. Participative research on use of enhanced climate variability information within agribusiness

    OpenAIRE

    Brennan, Lisa E.; Carberry, Peter S.; Hochman, Zvi

    2001-01-01

    Climate variability impacts significantly on the agricultural service sector, affecting the operations and policies of agribusiness suppliers, banking and insurance companies. For example, bank lending policy and agribusiness advice was likely affected by recent El Niño drought events. Through consultation with agribusiness suppliers, banks and insurance companies, it is clear that their business operations and policies could benefit substantially from access to enhanced processes for dealing...

  2. Modelling studies on soil-mediated response to acid deposition and climate variability

    OpenAIRE

    Holmberg, Maria

    2003-01-01

    The impact of acidifying atmospheric precipitation and climate variability on forest soil was studied using three approaches: (i) dynamic process-oriented modelling, (ii) static vulnerability assessment, and (iii) non-linear response pattern identification. The dynamic soil acidification model MIDAS is presented, with applications at the plot and catchment scale in Norway, Sweden and Finland, which show that growing vegetation contributes to soil acidification and which illustrate that the re...

  3. Responses of Montane Forest to Climate Variability in the Central Himalayas of Nepal

    Directory of Open Access Journals (Sweden)

    Janardan Mainali

    2015-02-01

    Full Text Available Climate changes are having dramatic ecological impacts in mid- to high-latitude mountain ranges where growth conditions are limited by climatic variables such as duration of growing season, moisture, and ambient temperature. We document patterns of forest vegetative response for 5 major alpine forest communities to current climate variability in the central Himalayas of Nepal to provide a baseline for assessment of future changes, as well as offer some insight into the trajectory of these changes over time. We used mean monthly surface air temperature and rainfall and the monthly averaged normalized difference vegetation index (NDVI to compare relative vegetation productivity among forest types and in relation to both climatic variables. Because changes in temperature and precipitation are directly manifested as changes in phenology, we examined current vegetative responses to climate variability in an effort to determine which climate variable is most critical for different alpine forest types. Our results show that correlations differ according to vegetation type and confirm that both precipitation and temperature affect monthly NDVI values, though more significant correlations were found with temperature data. The temperature response was more consistent because at the maximum increased temperatures, there was still an ongoing increase in vegetative vigor. This indicates that temperature is still the major limiting factor for plant growth at higher-elevation sites. This part of the Himalayas has abundant moisture, and some forest types are already saturated in terms of growth in relation to precipitation. Clear increases in productivity are documented on the upper treeline ecotones, and these systems are likely to continue to have increasing growth rates.

  4. Transport impacts on atmosphere and climate: Aviation

    Science.gov (United States)

    Lee, D. S.; Pitari, G.; Grewe, V.; Gierens, K.; Penner, J. E.; Petzold, A.; Prather, M. J.; Schumann, U.; Bais, A.; Berntsen, T.; Iachetti, D.; Lim, L. L.; Sausen, R.

    2010-12-01

    Aviation alters the composition of the atmosphere globally and can thus drive climate change and ozone depletion. The last major international assessment of these impacts was made by the Intergovernmental Panel on Climate Change (IPCC) in 1999. Here, a comprehensive updated assessment of aviation is provided. Scientific advances since the 1999 assessment have reduced key uncertainties, sharpening the quantitative evaluation, yet the basic conclusions remain the same. The climate impact of aviation is driven by long-term impacts from CO 2 emissions and shorter-term impacts from non-CO 2 emissions and effects, which include the emissions of water vapour, particles and nitrogen oxides (NO x). The present-day radiative forcing from aviation (2005) is estimated to be 55 mW m -2 (excluding cirrus cloud enhancement), which represents some 3.5% (range 1.3-10%, 90% likelihood range) of current anthropogenic forcing, or 78 mW m -2 including cirrus cloud enhancement, representing 4.9% of current forcing (range 2-14%, 90% likelihood range). According to two SRES-compatible scenarios, future forcings may increase by factors of 3-4 over 2000 levels, in 2050. The effects of aviation emissions of CO 2 on global mean surface temperature last for many hundreds of years (in common with other sources), whilst its non-CO 2 effects on temperature last for decades. Much progress has been made in the last ten years on characterizing emissions, although major uncertainties remain over the nature of particles. Emissions of NO x result in production of ozone, a climate warming gas, and the reduction of ambient methane (a cooling effect) although the overall balance is warming, based upon current understanding. These NO x emissions from current subsonic aviation do not appear to deplete stratospheric ozone. Despite the progress made on modelling aviation's impacts on tropospheric chemistry, there remains a significant spread in model results. The knowledge of aviation's impacts on cloudiness

  5. Uncertainty and sensitivity analysis of the retrieved essential climate variables from remotely sensed observations

    Science.gov (United States)

    Djepa, Vera; Badii, Atta

    2016-04-01

    The sensitivity of weather and climate system to sea ice thickness (SIT), Sea Ice Draft (SID) and Snow Depth (SD) in the Arctic is recognized from various studies. Decrease in SIT will affect atmospheric circulation, temperature, precipitation and wind speed in the Arctic and beyond. Ice thermodynamics and dynamic properties depend strongly on sea Ice Density (ID) and SD. SIT, SID, ID and SD are sensitive to environmental changes in the Polar region and impact the climate system. For accurate forecast of climate change, sea ice mass balance, ocean circulation and sea- atmosphere interactions it is required to have long term records of SIT, SID, SD and ID with errors and uncertainty analyses. The SID, SIT, ID and freeboard (F) have been retrieved from Radar Altimeter (RA) (on board ENVISAT) and IceBridge Laser Altimeter (LA) and validated, using over 10 years -collocated observations of SID and SD in the Arctic, provided from the European Space Agency (ESA CCI sea ice ECV project). Improved algorithms to retrieve SIT from LA and RA have been derived, applying statistical analysis. The snow depth is obtained from AMSR-E/Aqua and NASA IceBridge Snow Depth radar. The sea ice properties of pancake ice have been retrieved from ENVISAT/Synthetic Aperture Radar (ASAR). The uncertainties of the retrieved climate variables have been analysed and the impact of snow depth and sea ice density on retrieved SIT has been estimated. The sensitivity analysis illustrates the impact of uncertainties of input climate variables (ID and SD) on accuracy of the retrieved output variables (SIT and SID). The developed methodology of uncertainty and sensitivity analysis is essential for assessment of the impact of environmental variables on climate change and better understanding of the relationship between input and output variables. The uncertainty analysis quantifies the uncertainties of the model results and the sensitivity analysis evaluates the contribution of each input variable to

  6. Global warming and climate change in Amazonia: Climate-vegetation feedback and impacts on water resources

    Science.gov (United States)

    Marengo, José; Nobre, Carlos A.; Betts, Richard A.; Cox, Peter M.; Sampaio, Gilvan; Salazar, Luis

    This chapter constitutes an updated review of long-term climate variability and change in the Amazon region, based on observational data spanning more than 50 years of records and on climate-change modeling studies. We start with the early experiments on Amazon deforestation in the late 1970s, and the evolution of these experiments to the latest studies on greenhouse gases emission scenarios and land use changes until the end of the twenty-first century. The "Amazon dieback" simulated by the HadCM3 model occurs after a "tipping point" of CO2 concentration and warming. Experiments on Amazon deforestation and change of climate suggest that once a critical deforestation threshold (or tipping point) of 40-50% forest loss is reached in eastern Amazonia, climate would change in a way which is dangerous for the remaining forest. This may favor a collapse of the tropical forest, with a substitution of the forest by savanna-type vegetation. The concept of "dangerous climate change," as a climate change, which induces positive feedback, which accelerate the change, is strongly linked to the occurrence of tipping points, and it can be explained as the presence of feedback between climate change and the carbon cycle, particularly involving a weakening of the current terrestrial carbon sink and a possible reversal from a sink (as in present climate) to a source by the year 2050. We must, therefore, currently consider the drying simulated by the Hadley Centre model(s) as having a finite probability under global warming, with a potentially enormous impact, but with some degree of uncertainty.

  7. How weather impacts the forced climate response

    Energy Technology Data Exchange (ETDEWEB)

    Kirtman, Ben P. [University of Miami, Division of Meteorology and Physical Oceanography, Rosenstiel School for Atmospheric and Marine Science, Miami, FL (United States); Center for Ocean-Land-Atmosphere Studies, Calverton, MD (United States); Schneider, Edwin K.; Straus, David M. [George Mason University, Department of Atmospheric, Oceanic and Earth Sciences, Fairfax, VA (United States); Center for Ocean-Land-Atmosphere Studies, Calverton, MD (United States); Min, Dughong; Burgman, Robert [University of Miami, Division of Meteorology and Physical Oceanography, Rosenstiel School for Atmospheric and Marine Science, Miami, FL (United States)

    2011-12-15

    The new interactive ensemble modeling strategy is used to diagnose how noise due to internal atmospheric dynamics impacts the forced climate response during the twentieth century (i.e., 1870-1999). The interactive ensemble uses multiple realizations of the atmospheric component model coupled to a single realization of the land, ocean and ice component models in order to reduce the noise due to internal atmospheric dynamics in the flux exchange at the interface of the component models. A control ensemble of so-called climate of the twentieth century simulations of the Community Climate Simulation Model version 3 (CCSM3) are compared with a similar simulation with the interactive ensemble version of CCSM3. Despite substantial differences in the overall mean climate, the global mean trends in surface temperature, 500 mb geopotential and precipitation are largely indistinguishable between the control ensemble and the interactive ensemble. Large differences in the forced response; however, are detected particularly in the surface temperature of the North Atlantic. Associated with the forced North Atlantic surface temperature differences are local differences in the forced precipitation and a substantial remote rainfall response in the deep tropical Pacific. We also introduce a simple variance analysis to separately compare the variance due to noise and the forced response. We find that the noise variance is decreased when external forcing is included. In terms of the forced variance, we find that the interactive ensemble increases this variance relative to the control. (orig.)

  8. Climate Change Impacts on Marine Ecosystems

    Science.gov (United States)

    Doney, Scott C.; Ruckelshaus, Mary; Emmett Duffy, J.; Barry, James P.; Chan, Francis; English, Chad A.; Galindo, Heather M.; Grebmeier, Jacqueline M.; Hollowed, Anne B.; Knowlton, Nancy; Polovina, Jeffrey; Rabalais, Nancy N.; Sydeman, William J.; Talley, Lynne D.

    2012-01-01

    In marine ecosystems, rising atmospheric CO2 and climate change are associated with concurrent shifts in temperature, circulation, stratification, nutrient input, oxygen content, and ocean acidification, with potentially wide-ranging biological effects. Population-level shifts are occurring because of physiological intolerance to new environments, altered dispersal patterns, and changes in species interactions. Together with local climate-driven invasion and extinction, these processes result in altered community structure and diversity, including possible emergence of novel ecosystems. Impacts are particularly striking for the poles and the tropics, because of the sensitivity of polar ecosystems to sea-ice retreat and poleward species migrations as well as the sensitivity of coral-algal symbiosis to minor increases in temperature. Midlatitude upwelling systems, like the California Current, exhibit strong linkages between climate and species distributions, phenology, and demography. Aggregated effects may modify energy and material flows as well as biogeochemical cycles, eventually impacting the overall ecosystem functioning and services upon which people and societies depend.

  9. Climate change impact on available water resources obtained using multiple global climate and hydrology models

    OpenAIRE

    Hagemann, S.; Chen, Cui; Clark, D.B.; S. Folwell; Gosling, S.; Haddeland, I.; Hanasaki, N.; J. Heinke; F. Ludwig

    2012-01-01

    Climate change is expected to alter the hydrological cycle resulting in large-scale impacts on water availability. However, future climate change impact assessments are highly uncertain. For the first time, multiple global climate (three) and hydrological 5 models (eight) were used to systematically assess the hydrological response to climate change and project the future state of global water resources. The results show a large spread in projected changes in water resources within the climat...

  10. Mapping climate change impact on vegetation and the associated uncertainties in the Euro-Mediterranean area

    Science.gov (United States)

    Laanaia, Nabil; Calvet, Jean-Christophe; Carrer, Dominique; Séférian, Roland

    2016-04-01

    Crops, grasslands and forests in the Euro-Mediterranean area are already affected by the climate change impacts and will be even more in the future. The knowledge of the extent of these impacts will allow the implementation of adaptation strategies of agriculture and forestry to climate change. The aim of this study is to explore the potential implications of climate change and characterize significant future vegetation trends and their uncertainties. The ISBA (Interactions between Soil, Biosphere, and Atmosphere), land surface model is developed by Meteo-France for meteorological, hydrological and climatic applications. In this study, ISBA is forced by the atmospheric variables produced by different climate models. We use an ensemble of four climate models, following the RCP8.5 scenario, to drive the ISBA model. The simulations cover 114 year from 1986 to 2099. Two time horizons 2029-2058 (near future) and 2070-2099 (distant future) are compared to the 1988-2017 period. The ISBA model is used to provide several simulations of plant growth and carbon storage. Four vegetation types (rainfed straw cereals and grasslands, broadleaf and coniferous forests) are considered. The leaf area index simulations are used to determine phenology variables (leaf onset, leaf offset). A statistical analysis is used to quantify the impact of climate change and to show whether the future trends are significant or not. The uncertainties related to these trends are characterized. A spatial classification method is used to map the spatial variability of the impact of climate change.

  11. Demonstrating the climate4impact portal: bridging the CMIP5 data infrastructure to impact users

    Science.gov (United States)

    Plieger, Maarten; Som de Cerff, Wim; Page, Christian; Hutjes, Ronald; de Jong, Fokke; Bärring, Lars; Sjökvist, Elin

    2013-04-01

    Together with seven other partners (CERFACS, CNRS-IPSL, SMHI, INHGA, CMCC, WUR, MF-CNRM), KNMI is involved in the FP7 project IS-ENES (http://is.enes.org), which supports the European climate modeling infrastructure, in the work package 'Bridging Climate Research Data and the Needs of the Impact Community'. The aim of this work package is to enhance the use of climate model data and to enhance the interaction with climate effect/impact communities. The portal is based on 17 impact use cases from 5 different European countries, and is evaluated by a user panel consisting of use case owners. As the climate impact community is very broad, the focus is mainly on the scientific impact community. This work has resulted in a prototype portal, the ENES portal interface for climate impact communities, that can be visited at www.climate4impact.eu. The portal is connected to all Earth System Grid Federation (ESGF) nodes containing global climate model data (GCM data) from the fifth phase of the Coupled Model Intercomparison Project (CMIP5) and later from the Coordinated Regional Climate Downscaling Experiment (CORDEX). This global network of all major climate model data centers offers services for data description, discovery and download. The climate4impact portal connects to these services and offers a user interface for searching, visualizing and downloading global climate model data and more. During the project, the content management system Drupal was used to enable partners to contribute on the documentation section. The following topics will be demonstrated: - Security: Login using OpenID for access to the ESG data nodes. The ESG works in conjunction with several external websites and systems. The climate4impact portal uses X509 based short lived credentials, generated on behalf of the user with a MyProxy service. Single Sign-on (SSO) is used to make these websites and systems work together. - Discovery: Facetted search based on e.g. variable name, model and institute

  12. Assessment of Human Health Vulnerability to Climate Variability and Change in Cuba

    OpenAIRE

    Bultó, Paulo Lázaro Ortíz; Rodríguez, Antonio Pérez; Valencia, Alina Rivero; Vega, Nicolás León; Gonzalez, Manuel Díaz; Carrera, Alina Pérez

    2006-01-01

    In this study we assessed the potential effects of climate variability and change on population health in Cuba. We describe the climate of Cuba as well as the patterns of climate-sensitive diseases of primary concern, particularly dengue fever. Analyses of the associations between climatic anomalies and disease patterns highlight current vulnerability to climate variability. We describe current adaptations, including the application of climate predictions to prevent disease outbreaks. Finally...

  13. Assessment of a climate model to reproduce rainfall variability and extremes over Southern Africa

    Science.gov (United States)

    Williams, C. J. R.; Kniveton, D. R.; Layberry, R.

    2010-01-01

    It is increasingly accepted that any possible climate change will not only have an influence on mean climate but may also significantly alter climatic variability. A change in the distribution and magnitude of extreme rainfall events (associated with changing variability), such as droughts or flooding, may have a far greater impact on human and natural systems than a changing mean. This issue is of particular importance for environmentally vulnerable regions such as southern Africa. The sub-continent is considered especially vulnerable to and ill-equipped (in terms of adaptation) for extreme events, due to a number of factors including extensive poverty, famine, disease and political instability. Rainfall variability and the identification of rainfall extremes is a function of scale, so high spatial and temporal resolution data are preferred to identify extreme events and accurately predict future variability. The majority of previous climate model verification studies have compared model output with observational data at monthly timescales. In this research, the assessment of ability of a state of the art climate model to simulate climate at daily timescales is carried out using satellite-derived rainfall data from the Microwave Infrared Rainfall Algorithm (MIRA). This dataset covers the period from 1993 to 2002 and the whole of southern Africa at a spatial resolution of 0.1° longitude/latitude. This paper concentrates primarily on the ability of the model to simulate the spatial and temporal patterns of present-day rainfall variability over southern Africa and is not intended to discuss possible future changes in climate as these have been documented elsewhere. Simulations of current climate from the UK Meteorological Office Hadley Centre's climate model, in both regional and global mode, are firstly compared to the MIRA dataset at daily timescales. Secondly, the ability of the model to reproduce daily rainfall extremes is assessed, again by a comparison with

  14. Climate Variability and Household Adaptation Strategies in Southern Ethiopia

    Directory of Open Access Journals (Sweden)

    Wassie Berhanu

    2015-05-01

    Full Text Available This paper examines the determinants and implied economic impacts of climate change adaptation strategies in the context of traditional pastoralism. It is based on econometric analysis of survey data generated from household level interviews in southern Ethiopian rangelands. Pastoralists’ perception of climate change in the region is found to be very consistent with the actually recorded trends of increased temperature and the evident secular declines in precipitation. Not only long-term declines, trends in the region’s rainfall also appear to have taken a shift towards the direction of more unpredictability. Pastoralist adaptation response strategies broadly involve adjustments in pastoral practices and shifts to non-pastoral livelihoods. Results of the estimated models confirm that pastoral mobility is still quite essential in the present context of climate-induced household vulnerabilities. Increased mobility and diversification of pastoral herd portfolios in favor of a drought-tolerant species (camel are found to be positively associated with pastoral household net income. A policy stance that ignores the detrimental impacts of the currently pervasive private rangeland enclosures or intends to hasten pastoralist sedentarization in the area is simply untenable in the present context of climate-induced risks and pastoral livelihood vulnerability.

  15. Tajikistan - Economic and Distributional Impact of Climate Change

    OpenAIRE

    Heltberg, Rasmus; Reva, Anna; Zaidi, Salman

    2012-01-01

    Tajikistan is highly vulnerable to the adverse impacts of global climate change, as it already suffers from low agricultural productivity, water stress, and high losses from disasters. Public awareness of the multiple consequences of climate change is high, with possible impacts on health, natural disasters, and agriculture of greatest public concern. Climate change can potentially deepen ...

  16. Delivering CMIP5-based climate scenarios for impact assessments in Europe

    Science.gov (United States)

    Semenov, Mikhail

    2014-05-01

    Local-scale climate scenarios are required as input to impact models for assessment of climate change impacts. These scenarios incorporate changes in climatic variability as well as extreme events which are particularly important when used in conjunctions with process-based non-linear impact models. ELPIS is a repository of climate scenarios for Europe, which is based on the LARS-WG weather generator and future climate projections. Recently, projections from 18 global climate models (GCMs) from the CMIP5 multi-model ensembles used in the latest IPCC AR5 were incorporated into ELPIS. In ELPIS, the site parameters for climatic variables for the baseline period, 1980-2010, were estimated by LARS-WG from the European Crop Growth Monitoring System (CGMS) daily weather which were interpolated from observed sites over 25-km grid in Europe. Using change-factors derived from GCMs, LARS-WG perturbed site distributions for the baseline climate to generate local-scale daily weather for the future under RCP4.5 and RCP8.5 concentration pathways. The ability of LARS-WG to reproduce daily weather time series for 1980-2010 was assessed using statistical tests. Baseline site parameters, derived from CGMS, were validated against independent dataset obtained from the ECA&D archive. ELPIS represents a unique resource for impact assessments of climate change in Europe.

  17. Uncertainties in projecting climate-change impacts in marine ecosystems

    DEFF Research Database (Denmark)

    Payne, Mark; Barange, Manuel; Cheung, William W. L.;

    2016-01-01

    Projections of the impacts of climate change on marine ecosystems are a key prerequisite for the planning of adaptation strategies, yet they are inevitably associated with uncertainty. Identifying, quantifying, and communicating this uncertainty is key to both evaluating the risk associated with a...... projection and building confidence in its robustness. We review how uncertainties in such projections are handled in marine science. We employ an approach developed in climate modelling by breaking uncertainty down into (i) structural (model) uncertainty, (ii) initialization and internal variability...... uncertainty is rarely treated explicitly and reducing this type of uncertainty may deliver gains on the seasonal-to-decadal time-scale.Weconclude that all parts of marine science could benefit from a greater exchange of ideas, particularly concerning such a universal problem such as the treatment of...

  18. The climate4impact portal: bridging CMIP5 data to impact users

    Science.gov (United States)

    Som de Cerff, Wim; Plieger, Maarten; Page, Christian; Hutjes, Ronald; de Jong, Fokke; Barring, Lars; Sjökvist, Elin

    2013-04-01

    Together with seven other partners (CERFACS, CNRS-IPSL, SMHI, INHGA, CMCC, WUR, MF-CNRM), KNMI is involved in the FP7 project IS-ENES (http://is.enes.org), which supports the European climate modeling infrastructure, in the work package 'Bridging Climate Research Data and the Needs of the Impact Community'. The aim of this work package is to enhance the use of climate model data and to enhance the interaction with climate effect/impact communities. The portal is based on 17 impact use cases from 5 different European countries, and is evaluated by a user panel consisting of use case owners. As the climate impact community is very broad, the focus is mainly on the scientific impact community. This work has resulted in a prototype portal, the ENES portal interface for climate impact communities, that can be visited at www.climate4impact.eu. The portal is connected to all Earth System Grid Federation (ESGF) nodes containing global climate model data (GCM data) from the fifth phase of the Coupled Model Intercomparison Project (CMIP5) and later from the Coordinated Regional Climate Downscaling Experiment (CORDEX). This global network of all major climate model data centers offers services for data description, discovery and download. The climate4impact portal connects to these services and offers a user interface for searching, visualizing and downloading global climate model data and more. A challenging task was to describe the available model data and how it can be used. The portal tries to inform users about possible caveats when using model data. All impact use cases are described in the documentation section, using highlighted keywords pointing to detailed information in the glossary. The current portal is a Prototype. It is built to explore state-of-art technologies to provide improved access to climate model data. The prototype will be evaluated and is the basis for development of an operational service. The portal and services provided will be sustained and

  19. What's happening out there? (Climatic change impacts)

    International Nuclear Information System (INIS)

    This article briefly comments on some stumbling-blocks to climatic change modelling accuracy - in assessments of the greenhouse effect, 25% (missing link) of atmospheric carbon dioxide absorption is still unaccounted for; 1989 World Bank estimates of the Amazon rain forest deforestation rate have since proven to be inaccurate; there are difficulties in assessing the movement of the earth's crust relative to variations in sea level; and different studies vary in results relative to global temperature measurement and trend assessment. The need for an assessment of the economic impacts of increased atmospheric concentrations of carbon dioxide is also pointed out

  20. Amazonia: Burning and global climate impacts

    International Nuclear Information System (INIS)

    In recent years, humans have been playing a major role in reducing the natural forest cover in the tropics through different forms of slash and burn. The most serious destruction, it is said, is occurring in the Amazon, which is the largest expanse of tropical forest remaining on the planet. This chapter reviews briefly the causes and the extent of Amazonian deforestation and focuses on its global and local climate impacts. In addition, the effects of loss of diversity and need to preserve Indian cultures and societies are briefly discussed

  1. On the climatic impact of contrails

    Energy Technology Data Exchange (ETDEWEB)

    Strauss, B.; Meerkoetter, R.; Wissinger, B.; Wendling, P. [Deutsche Forschungs- und Versuchsanstalt fuer Luft- und Raumfahrt e.V., Oberpfaffenhofen (Germany). Inst. fuer Physik der Atmosphaere

    1997-12-31

    The impact of contrail induced cirrus clouds on regional climate is estimated for atmospheric conditions of Southern Germany that are typical for the months of July and October. This is done by the use of a regionalized one-dimensional radiative convective model (RCM). The influence of an increased ice cloud cover is studied by comparing RCM results using averaged climatological values of cloudiness with those of a case with modified cloudiness. It turns out that a 10% increase in ice cloud cover leads to a surface temperature increase of 1.4 K and 1.2 K for the months of July and October, respectively. (author) 14 refs.

  2. Assessing Regional Scale Variability in Extreme Value Statistics Under Altered Climate Scenarios

    Energy Technology Data Exchange (ETDEWEB)

    Brunsell, Nathaniel [University of Kansas; Mechem, David [University of Kansas; Ma, Chunsheng [Wichita State University

    2015-02-20

    Recent studies have suggested that low-frequency modes of climate variability can significantly influence regional climate. The climatology associated with extreme events has been shown to be particularly sensitive. This has profound implications for droughts, heat waves, and food production. We propose to examine regional climate simulations conducted over the continental United States by applying a recently developed technique which combines wavelet multi–resolution analysis with information theory metrics. This research is motivated by two fundamental questions concerning the spatial and temporal structure of extreme events. These questions are 1) what temporal scales of the extreme value distributions are most sensitive to alteration by low-frequency climate forcings and 2) what is the nature of the spatial structure of variation in these timescales? The primary objective is to assess to what extent information theory metrics can be useful in characterizing the nature of extreme weather phenomena. Specifically, we hypothesize that (1) changes in the nature of extreme events will impact the temporal probability density functions and that information theory metrics will be sensitive these changes and (2) via a wavelet multi–resolution analysis, we will be able to characterize the relative contribution of different timescales on the stochastic nature of extreme events. In order to address these hypotheses, we propose a unique combination of an established regional climate modeling approach and advanced statistical techniques to assess the effects of low-frequency modes on climate extremes over North America. The behavior of climate extremes in RCM simulations for the 20th century will be compared with statistics calculated from the United States Historical Climatology Network (USHCN) and simulations from the North American Regional Climate Change Assessment Program (NARCCAP). This effort will serve to establish the baseline behavior of climate extremes, the

  3. Future projection of Indian summer monsoon variability under climate change scenario: An assessment from CMIP5 climate models

    Science.gov (United States)

    Sharmila, S.; Joseph, S.; Sahai, A. K.; Abhilash, S.; Chattopadhyay, R.

    2015-01-01

    In this study, the impact of enhanced anthropogenic greenhouse gas emissions on the possible future changes in different aspects of daily-to-interannual variability of Indian summer monsoon (ISM) is systematically assessed using 20 coupled models participated in the Coupled Model Inter-comparison Project Phase 5. The historical (1951-1999) and future (2051-2099) simulations under the strongest Representative Concentration Pathway have been analyzed for this purpose. A few reliable models are selected based on their competence in simulating the basic features of present-climate ISM variability. The robust and consistent projections across the selected models suggest substantial changes in the ISM variability by the end of 21st century indicating strong sensitivity of ISM to global warming. On the seasonal scale, the all-India summer monsoon mean rainfall is likely to increase moderately in future, primarily governed by enhanced thermodynamic conditions due to atmospheric warming, but slightly offset by weakened large scale monsoon circulation. It is projected that the rainfall magnitude will increase over core monsoon zone in future climate, along with lengthening of the season due to late withdrawal. On interannual timescales, it is speculated that severity and frequency of both strong monsoon (SM) and weak monsoon (WM) might increase noticeably in future climate. Substantial changes in the daily variability of ISM are also projected, which are largely associated with the increase in heavy rainfall events and decrease in both low rain-rate and number of wet days during future monsoon. On the subseasonal scale, the model projections depict considerable amplification of higher frequency (below 30 day mode) components; although the dominant northward propagating 30-70 day mode of monsoon intraseasonal oscillations may not change appreciably in a warmer climate. It is speculated that the enhanced high frequency mode of monsoon ISOs due to increased GHG induced warming

  4. Conceptual Model of Climate Change Impacts at LANL

    Energy Technology Data Exchange (ETDEWEB)

    Dewart, Jean Marie [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2016-05-17

    Goal 9 of the LANL FY15 Site Sustainability Plan (LANL 2014a) addresses Climate Change Adaptation. As part of Goal 9, the plan reviews many of the individual programs the Laboratory has initiated over the past 20 years to address climate change impacts to LANL (e.g. Wildland Fire Management Plan, Forest Management Plan, etc.). However, at that time, LANL did not yet have a comprehensive approach to climate change adaptation. To fill this gap, the FY15 Work Plan for the LANL Long Term Strategy for Environmental Stewardship and Sustainability (LANL 2015) included a goal of (1) establishing a comprehensive conceptual model of climate change impacts at LANL and (2) establishing specific climate change indices to measure climate change and impacts at Los Alamos. Establishing a conceptual model of climate change impacts will demonstrate that the Laboratory is addressing climate change impacts in a comprehensive manner. This paper fulfills the requirement of goal 1. The establishment of specific indices of climate change at Los Alamos (goal 2), will improve our ability to determine climate change vulnerabilities and assess risk. Future work will include prioritizing risks, evaluating options/technologies/costs, and where appropriate, taking actions. To develop a comprehensive conceptual model of climate change impacts, we selected the framework provided in the National Oceanic and Atmospheric Administration (NOAA) Climate Resilience Toolkit (http://toolkit.climate.gov/).

  5. Climate SPHINX: High-resolution present-day and future climate simulations with an improved representation of small-scale variability

    Science.gov (United States)

    Davini, Paolo; von Hardenberg, Jost; Corti, Susanna; Subramanian, Aneesh; Weisheimer, Antje; Christensen, Hannah; Juricke, Stephan; Palmer, Tim

    2016-04-01

    The PRACE Climate SPHINX project investigates the sensitivity of climate simulations to model resolution and stochastic parameterization. The EC-Earth Earth-System Model is used to explore the impact of stochastic physics in 30-years climate integrations as a function of model resolution (from 80km up to 16km for the atmosphere). The experiments include more than 70 simulations in both a historical scenario (1979-2008) and a climate change projection (2039-2068), using RCP8.5 CMIP5 forcing. A total amount of 20 million core hours will be used at end of the project (March 2016) and about 150 TBytes of post-processed data will be available to the climate community. Preliminary results show a clear improvement in the representation of climate variability over the Euro-Atlantic following resolution increase. More specifically, the well-known atmospheric blocking negative bias over Europe is definitely resolved. High resolution runs also show improved fidelity in representation of tropical variability - such as the MJO and its propagation - over the low resolution simulations. It is shown that including stochastic parameterization in the low resolution runs help to improve some of the aspects of the MJO propagation further. These findings show the importance of representing the impact of small scale processes on the large scale climate variability either explicitly (with high resolution simulations) or stochastically (in low resolution simulations).

  6. Intraseasonal and Interannual Variability of Mars Present Climate

    Science.gov (United States)

    Hollingsworth, Jeffery L.; Bridger, Alison F. C.; Haberle, Robert M.

    1996-01-01

    This is a Final Report for a Joint Research Interchange (JRI) between NASA Ames Research Center and San Jose State University, Department of Meteorology. The focus of this JRI has been to investigate the nature of intraseasonal and interannual variability of Mars'present climate. We have applied a three-dimensional climate model based on the full hydrostatic primitive equations to determine the spatial, but primarily, the temporal structures of the planet's large-scale circulation as it evolves during a given seasonal advance, and, over multi-annual cycles. The particular climate model applies simplified physical parameterizations and is computationally efficient. It could thus easily be integrated in a perpetual season or advancing season configuration, as well as over many Mars years. We have assessed both high and low-frequency components of the circulation (i.e., motions having periods of Omicron(2-10 days) or greater than Omicron(10 days), respectively). Results from this investigation have explored the basic issue whether Mars' climate system is naturally 'chaotic' associated with nonlinear interactions of the large-scale circulation-regardless of any allowance for year-to-year variations in external forcing mechanisms. Titles of papers presented at scientific conferences and a manuscript to be submitted to the scientific literature are provided. An overview of a areas for further investigation is also presented.

  7. Developing a National Climate Indicators System to Track Climate Changes, Impacts, Vulnerabilities, and Preparedness

    Science.gov (United States)

    Kenney, M. A.; Janetos, A. C.; Arndt, D.; Chen, R. S.; Pouyat, R.; Anderson, S. M.

    2013-12-01

    The National Climate Assessment (NCA) is being conducted under the auspices of the U.S. Global Change Research Program (USGCRP), pursuant to the Global Change Research Act of 1990, Section 106, which requires a report to Congress every 4 years. Part of the vision, which is now under development, for the sustained National Climate Assessment (NCA) process is a system of physical, ecological, and societal indicators that communicate key aspects of the physical climate, climate impacts, vulnerabilities, and preparedness for the purpose of informing both decision makers and the public with scientifically valid information that is useful to inform decision-making processes such as the development and implementation of climate adaptation strategies in a particular sector or region. These indicators will be tracked as a part of ongoing assessment activities, with adjustments as necessary to adapt to changing conditions and understanding. The indicators will be reviewed and updated so that the system adapts to new information. The NCA indicator system is not intended to serve as a vehicle for documenting rigorous cause and effect relationships. It is reasonable, however, for it to serve as a guide to those factors that affect the evolution of variability and change in the climate system, the resources and sectors of concern that are affected by it, and how society chooses to respond. Different components of the end-to-end climate issue serve as categories within which to organize an end-to-end system of indicators: Greenhouse Gas Emissions and Sinks, Atmospheric Composition, Physical Climate Variability and Change, Sectors and Resources of Concern, and Adaptation and Mitigation Responses. This framing has several advantages. It can be used to identify the different components of the end-to-end climate issue that both decision-makers and researchers are interested in. It is independent of scale, and therefore allows the indicators themselves to be described at spatial

  8. Developing a System of National Climate Assessment Indicators to Track Climate Change Impacts, Vulnerabilities, and Preparedness

    Science.gov (United States)

    Janetos, A. C.; Kenney, M. A.; Chen, R. S.; Arndt, D.

    2012-12-01

    The National Climate Assessment (NCA) is being conducted under the auspices of the U.S. Global Change Research Program (USGCRP), pursuant to the Global Change Research Act of 1990, Section 106, which requires a report to Congress every 4 years (http://globalchange.gov/what-we-do/assessment/). Part of the vision for the sustained National Climate Assessment (NCA) process is a system of physical, ecological, and societal indicators that communicate key aspects of the physical climate, climate impacts, vulnerabilities, and preparedness for the purpose of informing both decision makers and the public with scientifically valid information that is useful to inform decision-making processes such as the development and implementation of climate adaptation strategies in a particular sector or region. These indicators will be tracked as a part of ongoing assessment activities, with adjustments as necessary to adapt to changing conditions and understanding. The indicators will be reviewed and updated so that the system adapts to new information. The NCA indicator system is not intended to serve as a vehicle for documenting rigorous cause and effect relationships. It is reasonable, however, for it to serve as a guide to those factors that affect the evolution of variability and change in the climate system, the resources and sectors o