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Climate Change Scenarios (climate + change_scenario)
Selected AbstractsPerformance of High Arctic tundra plants improved during but deteriorated after exposure to a simulated extreme temperature eventGLOBAL CHANGE BIOLOGY, Issue 12 2005Fleur L. Marchand Abstract Arctic ecosystems are known to be extremely vulnerable to climate change. As the Intergovernmental Panel on Climate Change scenarios project extreme climate events to increase in frequency and severity, we exposed High Arctic tundra plots during 8 days in summer to a temperature rise of approximately 9°C, induced by infrared irradiation, followed by a recovery period. Increased plant growth rates during the heat wave, increased green cover at the end of the heat wave and higher chlorophyll concentrations of all four predominating species (Salix arctica Pall., Arctagrostis latifolia Griseb., Carex bigelowii Torr. ex Schwein and Polygonum viviparum L.) after the recovery period, indicated stimulation of vegetative growth. Improved plant performance during the heat wave was confirmed at plant level by higher leaf photochemical efficiency (Fv/Fm) and at ecosystem level by increased gross canopy photosynthesis. However, in the aftermath of the temperature extreme, the heated plants were more stressed than the unheated plants, probably because they acclimated to warmer conditions and experienced the return to (low) ambient as stressful. We also calculated the impact of the heat wave on the carbon balance of this tundra ecosystem. Below- and aboveground respiration were stimulated by the instantaneous warmer soil and canopy, respectively, outweighing the increased gross photosynthesis. As a result, during the heat wave, the heated plots were a smaller sink compared with their unheated counterparts, whereas afterwards the balance was not affected. If other High Arctic tundra ecosystems react similarly, more frequent extreme temperature events in a future climate may shift this biome towards a source. It is uncertain, however, whether these short-term effects will hold when C exchange rates acclimate to higher average temperatures. [source] Impacts of extreme winter warming in the sub-Arctic: growing season responses of dwarf shrub heathlandGLOBAL CHANGE BIOLOGY, Issue 11 2008S. BOKHORST Abstract Climate change scenarios predict an increased frequency of extreme climatic events. In Arctic regions, one of the most profound of these are extreme and sudden winter warming events in which temperatures increase rapidly to above freezing, often causing snow melt across whole landscapes and exposure of ecosystems to warm temperatures. Following warming, vegetation and soils no longer insulated below snow are then exposed to rapidly returning extreme cold. Using a new experimental facility established in sub-Arctic dwarf shrub heathland in northern Sweden, we simulated an extreme winter warming event in the field and report findings on growth, phenology and reproduction during the subsequent growing season. A 1-week long extreme winter warming event was simulated in early March using infrared heating lamps run with or without soil warming cables. Both single short events delayed bud development of Vaccinium myrtillus by up to 3 weeks in the following spring (June) and reduced flower production by more than 80%: this also led to a near-complete elimination of berry production in mid-summer. Empetrum hermaphroditum also showed delayed bud development. In contrast, Vaccinium vitis-idaea showed no delay in bud development, but instead appeared to produce a greater number of actively growing vegetative buds within plots warmed by heating lamps only. Again, there was evidence of reduced flowering and berry production in this species. While bud break was delayed, growing season measurements of growth and photosynthesis did not reveal a differential response in the warmed plants for any of the species. These results demonstrate that a single, short, extreme winter warming event can have considerable impact on bud production, phenology and reproductive effort of dominant plant species within sub-Arctic dwarf shrub heathland. Furthermore, large interspecific differences in sensitivity are seen. These findings are of considerable concern, because they suggest that repeated events may potentially impact on the biodiversity and productivity of these systems should these extreme events increase in frequency as a result of global change. Although climate change may lengthen the growing season by earlier spring snow melt, there is a profound danger for these high-latitude ecosystems if extreme, short-lived warming in winter exposes plants to initial warm temperatures, but then extreme cold for the rest of the winter. Work is ongoing to determine the longer term and wider impacts of these events. [source] Modelling the interannual variability of net ecosystem CO2 exchange at a subarctic sedge fenGLOBAL CHANGE BIOLOGY, Issue 5 2001Timothy J. Griffis Abstract This paper presents an empirical model of net ecosystem CO2 exchange (NEE) developed for a subarctic fen near Churchill, Manitoba. The model with observed data helps explain the interannual variability in growing season NEE. Five years of tower-flux data are used to test and examine the seasonal behaviour of the model simulations. Processes controlling the observed interannual variability of CO2 exchange at the fen are examined by exploring the sensitivity of the model to changes in air temperature, precipitation and leaf area index. Results indicate that the sensitivity of NEE to changing environmental controls is complex and varies interannually depending on the initial conditions of the wetland. Changes in air temperature and the timing of precipitation events have a strong influence on NEE, which is largely manifest in gross ecosystem photosynthesis (GEP). Climate change scenarios indicate that warmer air temperatures will increase carbon acquisition during wet years but may act to reduce wetland carbon storage in years that experience a large water deficit early in the growing season. Model simulations for this subarctic sedge fen indicate that carbon acquisition is greatest during wet and warm conditions. This suggests therefore that carbon accumulation was greatest at this subarctic fen during its early developmental stages when hydroclimatic conditions were relatively wet and warm at approximately 2500 years before present. [source] Climate change scenarios and models yield conflicting predictions about the future risk of an invasive species in North AmericaAGRICULTURAL AND FOREST ENTOMOLOGY, Issue 3 2010Anna M. Mika 1The pea leafminer Liriomyza huidobrensis (Blanchard) (Diptera: Agromyzidae) is an invasive species in North America and a serious economic pest on a wide variety of crops. We developed a bioclimatic envelope model (BEM) for this species and examined the envelope's potential location in North America under various future climates. 2We compared the future bioclimatic envelopes for L. huidobrensis using either simple scenarios comprising uniform changes in temperature/precipitation or climate projections from general circulation models (GCMs). Our simple scenarios were: (i) an increase of 0.1°C per degree in latitude with a 20% increase in summer precipitation and a 20% decrease in winter precipitation and (ii) an overall increase of 3°C everywhere, also with the same changes in precipitation. For GCM-modelled climate change, we used the Canadian Centre for Climate Modelling and Analysis GCM (CGCM2) and the Hadley Centre climate model (HadCM3), each in combination with two scenarios from the Special Report on Emissions Scenarios (A2 and B2). 3The BEM results using the simple scenarios were more similar to each other than to the results obtained using GCM projections. The results were also qualitatively different (i.e. spatially different and divergent) depending on which GCM-scenario combination was used. 4This modelling exercise illustrates that: (i) results using first approximation simple climate change scenarios can give predictions very different from those that use GCM-modelled climate projections (comprising a result that has worrying implications for empirical impact research) and that (ii) different GCM-models using the same scenario can give very different results (implying strong model dependency in projected biological impacts). [source] Teaching and Learning Guide for: The Geopolitics of Climate ChangeGEOGRAPHY COMPASS (ELECTRONIC), Issue 5 2008Jon Barnett Author's Introduction Climate change is a security problem in as much as the kinds of environmental changes that may result pose risks to peace and development. However, responsibilities for the causes of climate change, vulnerability to its effects, and capacity to solve the problem, are not equally distributed between countries, classes and cultures. There is no uniformity in the geopolitics of climate change, and this impedes solutions. Author Recommends 1.,Adger, W. N., et al. (eds) (2006). Fairness in adaptation to climate change. Cambridge, MA: MIT Press. A comprehensive collection of articles on the justice dimensions of adaptation to climate change. Chapters discuss potential points at which climate change becomes ,dangerous', the issue of adaptation under the United Nations Framework Convention on Climate Change (UNFCCC), the unequal outcomes of adaptation within a society, the effects of violent conflict on adaptation, the costs of adaptation, and examples from Bangladesh, Tanzania, Botswana, and Hungary. 2.,Leichenko, R., and O'Brien, K. (2008). Environmental change and globalization: double exposures. New York: Oxford University Press. This book uses examples from around the world to show the way global economic and political processes interact with environmental changes to create unequal outcomes within and across societies. A very clear demonstration of the way vulnerability to environmental change is as much driven by social processes as environmental ones, and how solutions lie within the realm of decisions about ,development' and ,environment'. 3.,Nordås, R., and Gleditsch, N. (2007). Climate conflict: common sense or nonsense? Political Geography 26 (6), pp. 627,638. doi:10.1016/j.polgeo.2007.06.003 An up-to-date, systematic and balanced review of research on the links between climate change and violent conflict. See also the other papers in this special issue of Political Geography. 4.,Parry, M., et al. (eds) (2007). Climate change 2007: impacts adaptation and vulnerability. Contribution of Working Group II to the fourth assessment report of the intergovernmental panel on climate change. Cambridge, UK: Cambridge University Press. The definitive review of all the peer-reviewed research on the way climate change may impact on places and sectors across the world. Includes chapters on ecosystems, health, human settlements, primary industries, water resources, and the major regions of the world. All chapters are available online at http://www.ipcc.ch/ipccreports/ar4-wg2.htm 5.,Salehyan, I. (2008). From climate change to conflict? No consensus yet. Journal of Peace Research 45 (3), pp. 315,326. doi:10.1177/0022343308088812 A balanced review of research on the links between climate change and conflict, with attention to existing evidence. 6.,Schwartz, P., and Randall, D. (2003). An abrupt climate change scenario and its implications for United States national security. San Francisco, CA: Global Business Network. Gives insight into how the US security policy community is framing the problem of climate change. This needs to be read critically. Available at http://www.gbn.com/ArticleDisplayServlet.srv?aid=26231 7.,German Advisory Council on Global Change. (2007). World in transition: climate change as a security risk. Berlin, Germany: WBGU. A major report from the German Advisory Council on Global Change on the risks climate changes poses to peace and stability. Needs to be read with caution. Summary and background studies are available online at http://www.wbgu.de/wbgu_jg2007_engl.html 8.,Yamin, F., and Depedge, J. (2004). The International climate change regime: a guide to rules, institutions and procedures. Cambridge, UK: Cambridge University Press. A clear and very detailed explanation of the UNFCCC's objectives, actors, history, and challenges. A must read for anyone seeking to understand the UNFCCC process, written by two scholars with practical experience in negotiations. Online Materials 1.,Environmental Change and Security Program at the Woodrow Wilson International Center for Scholars http://www.wilsoncenter.org/ecsp The major website for information about environmental security. From here, you can download many reports and studies, including the Environmental Change and Security Project Report. 2.,Global Environmental Change and Human Security Project http://www.gechs.org This website is a clearing house for work and events on environmental change and human security. 3.,Intergovernmental Panel on Climate Change (IPCC) http://www.ipcc.ch/ From this website, you can download all the chapters of all the IPCC's reports, including its comprehensive and highly influential assessment reports, the most recent of which was published in 2007. The IPCC were awarded of the Nobel Peace Prize ,for their efforts to build up and disseminate greater knowledge about man-made (sic) climate change, and to lay the foundations for the measures that are needed to counteract such change'. 4.,Tyndall Centre for Climate Change Research http://www.tyndall.ac.uk The website of a major centre for research on climate change, and probably the world's leading centre for social science based analysis of climate change. From this site, you can download many publications about mitigation of and adaptation to climate change, and about various issues in the UNFCCC. 5.,United Nations Framework Convention on Climate Change http://unfccc.int/ The website contains every major document relation to the UNFCCC and its Kyoto Protocol, including the text of the agreements, national communications, country submissions, negotiated outcomes, and background documents about most key issues. Sample Syllabus: The Geopolitics of Climate Change topics for lecture and discussion Week I: Introduction Barnett, J. (2007). The geopolitics of climate change. Geography Compass 1 (6), pp. 1361,1375. United Nations Secretary General, Kofi Annan, address to the 12th Conference of Parties to the United Nations Framework Convention on Climate Change, Nairobi, 15 November 2006. Available online at http://www.unep.org/Documents.Multilingual/Default.asp?DocumentID=495&ArticleID=5424&l=en Week II: The History and Geography of Greenhouse Gas Emissions Topic: The drivers of climate change in space and time Reading Baer, P. (2006). Adaptation: who pays whom? In: Adger, N., et al. (eds) Fairness in adaptation to climate change. Cambridge, MA: MIT Press, pp. 131,154. Boyden, S., and Dovers, S. (1992). Natural-resource consumption and its environmental impacts in the Western World: impacts of increasing per capita consumption. Ambio 21 (1), pp. 63,69. Week III: The Environmental Consequences of climate change Topic: The risks climate change poses to environmental systems Reading Intergovernmental Panel on Climate Change. (2007). Climate change 2007: climate change impacts, adaptation and vulnerability: summary for policymakers. Geneva, Switzerland: IPCC Secretariat. Watch: Al Gore. The Inconvenient Truth. Weeks IV and V: The Social Consequences of Climate Change Topic: The risks climate change poses to social systems Reading Adger, W. N. (1999). Social vulnerability to climate change and extremes in coastal Vietnam. World Development 27, pp. 249,269. Comrie, A. (2007). Climate change and human health. Geography Compass 1 (3), pp. 325,339. Leary, N., et al. (2006). For whom the bell tolls: vulnerability in a changing climate. A Synthesis from the AIACC project, AIACC Working Paper No. 21, International START Secretariat, Florida. Stern, N. (2007). Economics of climate change: the Stern review. Cambridge, UK: Cambridge University Press (Chapters 3,5). Week VI: Mitigation of Climate Change: The UNFCCC Topic: The UNFCCC and the Kyoto Protocol Reading Najam, A., Huq, S., and Sokona, Y. (2003). Climate negotiations beyond Kyoto: developing countries concerns and interests. Climate Policy 3 (3), pp. 221,231. UNFCCC Secretariat. (2005). Caring for climate: a guide to the climate change convention and the Kyoto Protocol. Bonn, Germany: UN Framework Convention on Climate Change Secretariat. Weeks VII and VIII: Adaptation to Climate Change Topic: What can be done to allow societies to adapt to avoid climate impacts? Reading Adger, N., et al. (2007). Assessment of adaptation practices, options, constraints and capacity. In: Parry, M., et al. (eds) Climate change 2007: impacts, adaptation and vulnerability. Contribution of Working Group II to the fourth assessment report of the intergovernmental panel on climate change. Cambridge, UK: Cambridge University Press, pp. 717,744. Burton, I., et al. (2002). From impacts assessment to adaptation priorities: the shaping of adaptation policy. Climate Policy 2 (2,3), pp. 145,159. Eakin, H., and Lemos, M. C. (2006). Adaptation and the state: Latin America and the challenge of capacity-building under globalization. Global Environmental Change: Human and Policy Dimensions 16 (1), pp. 7,18. Ziervogel, G., Bharwani, S., and Downing, T. (2006). Adapting to climate variability: pumpkins, people and policy. Natural Resources Forum 30, pp. 294,305. Weeks IX and X: Climate Change and Migration Topic: Will climate change force migration? Readings Gaim, K. (1997). Environmental causes and impact of refugee movements: a critique of the current debate. Disasters 21 (1), pp. 20,38. McLeman, R., and Smit, B. (2006). Migration as adaptation to climate change. Climatic Change 76 (1), pp. 31,53. Myers, N. (2002). Environmental refugees: a growing phenomenon of the 21st century. Philosophical Transactions of the Royal Society 357 (1420), pp. 609,613. Perch-Nielsen, S., Bättig, M., and Imboden, D. (2008). Exploring the link between climate change and migration. Climatic Change (online first, forthcoming); doi:10.1007/s10584-008-9416-y Weeks XI and XII: Climate Change and Violent Conflict Topic: Will Climate change cause violent conflict? Readings Barnett, J., and Adger, N. (2007). Climate change, human security and violent conflict. Political Geography 26 (6), pp. 639,655. Centre for Strategic and International Studies. (2007). The age of consequences: the foreign policy and national security implications of global climate change. Washington, DC: CSIS. Nordås, R., and Gleditsch, N. (2007). Climate conflict: common sense or nonsense? Political Geography 26 (6), pp. 627,638. Schwartz, P., and Randall, D. (2003). An abrupt climate change scenario and its implications for United States national security. San Francisco, CA: Global Business Network. [online]. Retrieved on 8 April 2007 from http://www.gbn.com/ArticleDisplayServlet.srv?aid=26231 Focus Questions 1Who is most responsible for climate change? 2Who is most vulnerable to climate change? 3Does everyone have equal power in the UNFCCC process? 4Will climate change force people to migrate? Who? 5What is the relationship between adaptation to climate change and violent conflict? [source] Genetic maladaptation of coastal Douglas-fir seedlings to future climatesGLOBAL CHANGE BIOLOGY, Issue 7 2007J. BRADLEY ST CLAIR Abstract Climates are expected to warm considerably over the next century, resulting in expectations that plant populations will not be adapted to future climates. We estimated the risk of maladaptation of current populations of coastal Douglas-fir (Pseudotsuga menziesii var. menziesii) to future climates as the proportion of nonoverlap between two normal distributions where the means and genetic variances of current and future populations are determined from genecological models derived from seedling common garden studies. The risk of maladaptation was large for most traits when compared with the risk associated with current transfers within seed zones, particularly for the more drastic climate change scenario. For example, the proportion of nonoverlap for a composite trait representing bud set, emergence, growth, and root : shoot ratio was as high as 0.90. We recommend augmenting within-population variation by mixing local populations with some proportion of populations from lower elevations and further south. Populations expected to be adapted to climates a century from now come from locations as far down in elevation as 450,1130 m and as far south in latitude as 1.8,4.9°. [source] Consequences of simultaneous elevation of carbon dioxide and temperature for plant,herbivore interactions: a metaanalysisGLOBAL CHANGE BIOLOGY, Issue 1 2006E. L. ZVEREVA Abstract The effects of elevated carbon dioxide on plant,herbivore interactions have been summarized in a number of narrative reviews and metaanalyses, while accompanying elevation of temperature has not received sufficient attention. The goal of our study is to search, by means of metaanalysis, for a general pattern in responses of herbivores, and plant characteristics important for herbivores, to simultaneous experimental increase of carbon dioxide and temperature (ECET) in comparison with both ambient conditions and responses to elevated CO2 (EC) and temperature (ET) applied separately. Our database includes 42 papers describing studies of 31 plant species and seven herbivore species. Nitrogen concentration and C/N ratio in plants decreased under both EC and ECET treatments, whereas ET had no significant effect. Concentrations of nonstructural carbohydrates and phenolics increased in EC, decreased in ET and did not change in ECET treatments, whereas terpenes did not respond to EC but increased in both ET and ECET; leaf toughness increased in both EC and ECET. Responses of defensive secondary compounds to treatments differed between woody and green tissues as well as between gymnosperm and angiosperm plants. Insect herbivore performance was adversely affected by EC, favoured by ET, and not modified by ECET. Our analysis allowed to distinguish three types of relationships between CO2 and temperature elevation: (1) responses to EC do not depend on temperature (nitrogen, C/N, leaf toughness, phenolics in angiosperm leaves), (2) responses to EC are mitigated by ET (sugars and starch, terpenes in needles of gymnosperms, insect performance) and (3) effects emerge only under ECET (nitrogen in gymnosperms, and phenolics and terpenes in woody tissues). This result indicates that conclusions of CO2 elevation studies cannot be directly extrapolated to a more realistic climate change scenario. The predicted negative effects of CO2 elevation on herbivores are likely to be mitigated by temperature increase. [source] Potential changes in the distributions of latitudinally restricted Australian butterfly species in response to climate changeGLOBAL CHANGE BIOLOGY, Issue 10 2002Linda J. Beaumont Abstract This study assessed potential changes in the distributions of Australian butterfly species in response to global warming. The bioclimatic program, BIOCLIM, was used to determine the current climatic ranges of 77 butterfly species restricted to Australia. We found that the majority of these species had fairly wide climatic ranges in comparison to other taxa, with only 8% of butterfly species having a mean annual temperature range spanning less than 3 °C. The potential changes in the distributions of 24 butterfly species under four climate change scenarios for 2050 were also modelled using BIOCLIM. Results suggested that even species with currently wide climatic ranges may still be vulnerable to climate change; under a very conservative climate change scenario (with a temperature increase of 0.8,1.4 °C by 2050) 88% of species distributions decreased, and 54% of species distributions decreased by at least 20%. Under an extreme scenario (temperature increase of 2.1,3.9 °C by 2050) 92% of species distributions decreased, and 83% of species distributions decreased by at least 50%. Furthermore, the proportion of the current range that was contained within the predicted range decreased from an average of 63% under a very conservative scenario to less than 22% under the most extreme scenario. By assessing the climatic ranges that species are currently exposed to, the extent of potential changes in distributions in response to climate change and details of their life histories, we identified species whose characteristics may make them particularly vulnerable to climate change in the future. [source] Stemwood volume increment changes in European forests due to climate change,a simulation study with the EFISCEN modelGLOBAL CHANGE BIOLOGY, Issue 4 2002Gert-Jan Nabuurs Abstract This paper presents the results of a modelling study of future net annual increment changes in stemwood of European forests owing to climate change. Seven process-based growth models were applied to 14 representative forest sites across Europe under one climate change scenario. The chosen scenario was the HadCM2 run, based on emission scenario IS92a, and resulted in an increase in mean temperature of 2.5 °C between 1990 and 2050, and an increase in annual precipitation of 5,15%. The information from those runs was incorporated in a transient way in a large-scale forest resource scenario model, EFISCEN (European forest information scenario). European scale forest resource projections were made for 28 countries covering 131.7 million ha of forest under two management scenarios for the period until 2050. The results showed that net annual increments in stemwood of European forests under climate change will further increase with an additional 0.9 m3 ha,1 y,1 in 2030 compared to the ongoing increase under a current climate scenario, i.e. an extra 18% increase. After 2030 the extra increment increase is reduced to 0.79 m3 ha,1 y,1 in 2050. Under climate change, absolute net annual increments will increase from the present 4.95, on average for Europe, to 5.93 m3 ha,1 y,1 in 2025. After 2025, increments in all scenarios start to decline owing to ageing of the forest and the high growing stocks being reached. The results of the present study are surrounded by large uncertainties. These uncertainties are caused by unknown emissions in the future, unknown extent of climate change, uncertainty in process-based models, uncertainty in inventory data, and uncertainty in inventory projection. Although the results are thus not conclusive, climate change may lead to extra felling opportunities in European forests of 87 million m3y,1. Because Europe's forests are intensively managed already, management may adapt to climate change relatively easily. However, this study also indicates that climate change may lead to a faster build-up of growing stocks. That may create a less stable forest resource in terms of risks to storm damage. [source] Modelling runoff from highly glacierized alpine drainage basins in a changing climateHYDROLOGICAL PROCESSES, Issue 19 2008Matthias Huss Abstract The future runoff from three highly glacierized alpine catchments is assessed for the period 2007,2100 using a glacio-hydrological model including the change in glacier coverage. We apply scenarios for the seasonal change in temperature and precipitation derived from regional climate models. Glacier surface mass balance and runoff are calculated in daily time-steps using a distributed temperature-index melt and accumulation model. Model components account for changes in glacier extent and surface elevation, evaporation and runoff routing. The model is calibrated and validated using decadal ice volume changes derived from four digital elevation models (DEMs) between 1962 and 2006, and monthly runoff measured at a gauging station (1979,2006). Annual runoff from the drainage basins shows an initial increase which is due to the release of water from glacial storage. After some decades, depending on catchment characteristics and the applied climate change scenario, runoff stabilizes and then drops below the current level. In all climate projections, the glacier area shrinks dramatically. There is an increase in runoff during spring and early summer, whereas the runoff in July and August decreases significantly. This study highlights the impact of glaciers and their future changes on runoff from high alpine drainage basins. Copyright © 2008 John Wiley & Sons, Ltd. [source] CLIMATE CHANGE IMPACTS ON WATER RESOURCES OF THE TSENGWEN CREEK WATERSHED IN TAIWAN,JOURNAL OF THE AMERICAN WATER RESOURCES ASSOCIATION, Issue 1 2001Ching-pin Tung ABSTRACT: This study presents a methodology to evaluate the vulnerability of water resources in the Tsengwen creek watershed, Taiwan. Tsengwen reservoir, located in the Tsengwen creek watershed, is a multipurpose reservoir with a primary function to supply water for the ChiaNan Irrigation District. A simulation procedure was developed to evaluate the impacts of climate change on the water resources system. The simulation procedure includes a streamflow model, a weather generation model, a sequent peak algorithm, and a risk assessment process. Three climate change scenarios were constructed based on the predictions of three General Circulation Models (CCCM, GFDL, and GISS). The impacts of climate change on streamflows were simulated, and, for each climate change scenario, the agricultural water demand was adjusted based on the change of potential evapotranspiration. Simulation results indicated that the climate change may increase the annual and seasonal streamflows in the Tsengwen creek watershed. The increase in streamflows during wet periods may result in serious flooding. In addition, despite the increase in streamflows, the risk of water deficit may still increase from between 4 and 7 percent to between 7 and 13 percent due to higher agricultural water demand. The simulation results suggest that the reservoir capacity may need to be expanded. In response to the climate change, four strategies are suggested: (1) strengthen flood mitigation measures, (2) enhance drought protection strategies, (3) develop new water resources technology, and (4) educate the public. [source] Probability distributions, vulnerability and sensitivity in Fagus crenata forests following predicted climate changes in JapanJOURNAL OF VEGETATION SCIENCE, Issue 5 2004Tetsuya Matsui Question: How much is the probability distribution of Fagus crenata forests predicted to change under a climate change scenario by the 2090s, and what are the potential impacts on these forests? What are the main factors inducing such changes? Location: The major islands of Japan. Methods: A predictive distribution model was developed with four climatic factors (summer precipitation, PRS; winter precipitation, PRW; minimum temperature of the coldest month, TMC; and warmth index, WI) and five non-climatic factors (topography, surface geology, soil, slope aspect and inclination). A climate change scenario was applied to the model. Results: Areas with high probability (> 0.5) were predicted to decrease by 91%, retreating from the southwest, shrinking in central regions, and expanding northeastwards beyond their current northern limits. A vulnerability index (the reciprocal of the predicted probability) suggests that Kyushu, Shikoku, the Pacific Ocean side of Honshu and southwest Hokkaido will have high numbers of many vulnerable F. crenata forests. The forests with high negative sensitivity indices (the difference between simulated probabilities of occurrence under current and predicted climates) mainly occur in southwest Hokkaido and the Sea of Japan side of northern Honshu. Conclusion: F. crenata forest distributions may retreat from some islands due to a high WI. The predicted northeastward shift in northern Hokkaido is associated with increased TMC and PRS. High vulnerability and negative sensitivity of the forests in southern Hokkaido are due to increased WI. [source] Weather, climate, and farmers: an overviewMETEOROLOGICAL APPLICATIONS, Issue S1 2006Roger C. Stone Abstract Challenges in linking meteorological and climatological information with a wide range of farming decisions are addressed in this paper. In particular, while a considerable amount of weather and climate information is now available for farmers, some types of information under development or already operational, particularly climate forecasting, formation, may be ill-suited for use by farmers for their decision-making. Case studies show it is particularly important for those key farm decisions that are amenable to weather and climate information to be identified clearly so that weather and climate information can be better tailored to suit farming decisions. A participatory approach provides farmers with ownership of the processes associated with development of weather and climate information and facilitates advances in linking climate and weather information and forecasts to farm decisions. Decision-support systems provide useful output when used with farmer discussion groups. Developing appropriate interdisciplinary systems to connect climate, weather, and agronomic information, especially including forecasting systems, with farm management is needed if uptake of weather and climate information by farmers is to be successful. Provision of output of climate change scenario and trend information to aid long-term strategic farm management decisions needs to be considered, especially in regions where more vulnerable farming zones exist. Copyright © 2006 Royal Meteorological Society [source] The geography of climate change: implications for conservation biogeographyDIVERSITY AND DISTRIBUTIONS, Issue 3 2010D. D. Ackerly Abstract Aim, Climate change poses significant threats to biodiversity, including impacts on species distributions, abundance and ecological interactions. At a landscape scale, these impacts, and biotic responses such as adaptation and migration, will be mediated by spatial heterogeneity in climate and climate change. We examine several aspects of the geography of climate change and their significance for biodiversity conservation. Location, California and Nevada, USA. Methods, Using current climate surfaces (PRISM) and two scenarios of future climate (A1b, 2070,2099, warmer-drier and warmer-wetter), we mapped disappearing, declining, expanding and novel climates, and the velocity and direction of climate change in California and Nevada. We also examined fine-scale spatial heterogeneity in protected areas of the San Francisco Bay Area in relation to reserve size, topographic complexity and distance from the ocean. Results, Under the two climate change scenarios, current climates across most of California and Nevada will shrink greatly in extent, and the climates of the highest peaks will disappear from this region. Expanding and novel climates are projected for the Central Valley. Current temperature isoclines are projected to move up to 4.9 km year,1 in flatter regions, but substantially slower in mountainous areas because of steep local topoclimate gradients. In the San Francisco Bay Area, climate diversity within currently protected areas increases with reserve size and proximity to the ocean (the latter because of strong coastal climate gradients). However, by 2100 of almost 500 protected areas (>100 ha), only eight of the largest are projected to experience temperatures within their currently observed range. Topoclimate variability will further increase the range of conditions experienced and needs to be incorporated in future analyses. Main Conclusions, Spatial heterogeneity in climate, from mesoclimate to topoclimate scales, represents an important spatial buffer in response to climate change, and merits increased attention in conservation planning. [source] Predicting the impact of climate change on Australia's most endangered snake, Hoplocephalus bungaroidesDIVERSITY AND DISTRIBUTIONS, Issue 1 2010Trent D. Penman Abstract Aim, To predict how the bioclimatic envelope of the broad-headed snake (BHS) (Hoplocephalus bungaroides) may be redistributed under future climate warming scenarios. Location, South-eastern New South Wales, Australia. Methods, We used 159 independent locations for the species and 35 climatic variables to model the bioclimatic envelope for the BHS using two modelling approaches , Bioclim and Maxent. Predictions were made under current climatic conditions and we also predicted the species distribution under low and high climate change scenarios for 2030 and 2070. Results, Broad-headed snakes currently encompass their entire bioclimatic envelope. Both modelling approaches predict that suitable climate space for BHS will be lost to varying degrees under both climate warming scenarios, and under the worst case, only 14% of known snake populations may persist. Main conclusions, Areas of higher elevation within the current range will be most important for persistence of this species because they will remain relatively moist and cool even under climate change and will match the current climate envelope. Conservation efforts should focus on areas where suitable climate space may persist under climate warming scenarios. Long-term monitoring programs should be established both in these areas and where populations are predicted to become extirpated, so that we can accurately determine changes in the distribution of this species throughout its range. [source] Effects of temperature and sediment properties on benthic CO2 production in an oligotrophic boreal lakeFRESHWATER BIOLOGY, Issue 8 2010IRINA BERGSTRÖM Summary 1. Temperature and many other physical and chemical factors affecting CO2 production in lake sediments vary significantly both seasonally and spatially. The effects of temperature and sediment properties on benthic CO2 production were studied in in situ and in vitro experiments in the boreal oligotrophic Lake Pääjärvi, southern Finland. 2. In in situ experiments, temperature of the water overlying the shallow littoral sediment varied seasonally between 0.5 and 15.7 °C, but in deep water (,20 m) the range was only 1.1,6.6 °C. The same exponential model (r2 = 0.70) described the temperature dependence at 1.2, 10 and 20 m depths. At 2.5 and 5 m depths, however, the slopes of the two regression models (r2 = 0.94) were identical but the intercept values were different. Sediment properties (wet, dry, mineral and organic mass) varied seasonally and with depth, but they did not explain a significantly larger proportion of variation in the CO2 output rate than temperature. 3. In in vitro experiments, there was a clear and uniform exponential dependence of CO2 production on temperature, with a 2.7-fold increase per 10 °C temperature rise. The temperature response (slope of regression) was always the same, but the basic value of CO2 production (intercept) varied, indicating that other factors also contributed to the benthic CO2 output rate. 4. The annual CO2 production of the sediment in Lake Pääjärvi averaged 62 g CO2 m,2, the shallow littoral at 0,3 m depth releasing 114 g CO2 m,2 and deep profundal (>15 m) 30 g CO2 m,2. On the whole lake basis, the shallow littoral at 0,3 m depth accounted for 53% and the sediment area in contact with the summer epilimnion (down to a depth c. 10 m) 75% of the estimated total annual CO2 output of the lake sediment, respectively. Of the annual production, 83% was released during the spring and summer. 5. Using the temperature-CO2 production equations and climate change scenarios we estimated that climatic warming might increase littoral benthic CO2 production in summer by nearly 30% from the period 1961,90 to the period 2071,2100. [source] A model for predicting the emergence of dragonflies in a changing climateFRESHWATER BIOLOGY, Issue 9 2008OTTO RICHTER Summary 1. Precise models for the phenology of different species are essential for predicting the potential effects of any temporal mismatch of life cycles with environmental parameters under different climate change scenarios. Here we investigated the effects of ambient water temperature on the onset and synchrony of emergence for a widespread European riverine dragonfly, Gomphus vulgatissimus. 2. Long-term field data on the annual emergence from two rivers in northern Germany, and additional data from a laboratory experiment with different temperature regimes, were used to develop a model that predicted the onset of emergence by using mainly the temperature sum (degree days) as a parameter. 3. Model predictions of the onset of emergence fitted the observations well and could be transferred between localities. This was particularly so when weighting early winter temperature data by using a day length and a temperature-response function, implying potential additional control mechanisms for the onset of emergence. 4. We simulated effects of different winter temperature regimes on the emergence curves in order to predict the effects of climate change. These indicated an acceleration of emergence by 6,7 days per 1 °C temperature increase, which is corroborated by the laboratory data and is in the upper range of data published for other dragonflies. [source] Use of tree rings to study the effect of climate change on trembling aspen in QuébecGLOBAL CHANGE BIOLOGY, Issue 7 2010MARIE-PIERRE LAPOINTE-GARANT Abstract In this paper, we present a new approach, based on a mixed model procedure, to quantify the tree-ring-based growth-climate relationship of trembling aspen along a latitudinal gradient from 46 to 54 °N in eastern Canada. This approach allows breaking down the growth response into general intersite and local climatic responses, and analyzing variations of absolute ring width as well as interannual variations in tree growth. The final model also integrates nonclimatic variables such as soil characteristics and the occurrence of insect outbreaks into the growth predictions. Tree level random effects on growth were important as intercepts but were nonsignificant for the climatic variables, indicating that a single climate,growth relationship was justified in our case. The response of tree growth to climate showed, however, a strong dependence on the spatial scale at which the analysis was performed. Intersite variations in tree growth were mostly dependent on variations in the thermal heat sum, a variable that showed low interannual and high intersite variation. When variation for a single site was analyzed, other variables showed up to be important while the heat sum was unimportant. Finally, future growth under six different climate change scenarios was simulated in order to study the potential impact of climate change. Results suggest only moderate growth increases in the northern portion of the gradient and a growth decrease in the southern portion under future climatic conditions. [source] Spatial scale affects bioclimate model projections of climate change impacts on mountain plantsGLOBAL CHANGE BIOLOGY, Issue 5 2008MANDAR R. TRIVEDI Abstract Plant species have responded to recent increases in global temperatures by shifting their geographical ranges poleward and to higher altitudes. Bioclimate models project future range contractions of montane species as suitable climate space shifts uphill. The species,climate relationships underlying such models are calibrated using data at either ,macro' scales (coarse resolution, e.g. 50 km × 50 km, and large spatial extent) or ,local' scales (fine resolution, e.g. 50 m × 50 m, and small spatial extent), but the two approaches have not been compared. This study projected macro (European) and local models for vascular plants at a mountain range in Scotland, UK, under low (+1.7 °C) and high (+3.3 °C) climate change scenarios for the 2080s. Depending on scenario, the local models projected that seven or eight out of 10 focal montane species would lose all suitable climate space at the site. However, the European models projected such a loss for only one species. The cause of this divergence was investigated by cross-scale comparisons of estimated temperatures at montane species' warm range edges. The results indicate that European models overestimated species' thermal tolerances because the input coarse resolution climate data were biased against the cold, high-altitude habitats of montane plants. Although tests at other mountain ranges are required, these results indicate that recent large-scale modelling studies may have overestimated montane species' ability to cope with increasing temperatures, thereby underestimating the potential impacts of climate change. Furthermore, the results suggest that montane species persistence in microclimatic refugia might not be as widespread as previously speculated. [source] Voltinism flexibility of a riverine dragonfly along thermal gradientsGLOBAL CHANGE BIOLOGY, Issue 3 2008ERIK BRAUNE Abstract Potential effects of future warming should be reflected in life history patterns of aquatic organisms observed in warmer climates or in habitats that are different in ambient temperature. In the special case of the dragonfly Gomphus vulgatissimus (L.) (Odonata: Gomphidae) previous research suggests that voltinism decreases from south to north. We analysed data on voltinism from 11 sample sites along a latitudinal gradient from about 44°N to 53°N, comprising small streams to medium-sized rivers. Furthermore, to simulate different conditions and to allow projections for future climate change scenarios, we developed a population dynamic model based on a projection matrix approach. The parameters of the model are dependent on temperature and day length. Our field results indicate a decrease in voltinism along the latitudinal gradient from southern to northern Europe and a corresponding increase of voltinism with higher temperatures. An increase in voltinism with width of the running water implies an effect of varying habitat temperature. Under the impact of global warming, our model predicts an increased development speed, particularly in the northern part of the latitudinal gradient, an extension of the northern range limit and changes in phenology of G. vulgatissimus, leading to an extension of the flight season in certain regions along the gradient. [source] Use and misuse of the IUCN Red List Criteria in projecting climate change impacts on biodiversityGLOBAL CHANGE BIOLOGY, Issue 11 2006H. RESIT AKÇAKAYA Abstract Recent attempts at projecting climate change impacts on biodiversity have used the IUCN Red List Criteria to obtain estimates of extinction rates based on projected range shifts. In these studies, the Criteria are often misapplied, potentially introducing substantial bias and uncertainty. These misapplications include arbitrary changes to temporal and spatial scales; confusion of the spatial variables; and assume a linear relationship between abundance and range area. Using the IUCN Red List Criteria to identify which species are threatened by climate change presents special problems and uncertainties, especially for shorter-lived species. Responses of most species to future climate change are not understood well enough to estimate extinction risks based solely on climate change scenarios and projections of shifts and/or reductions in range areas. One way to further such understanding would be to analyze the interactions among habitat shifts, landscape structure and demography for a number of species, using a combination of models. Evaluating the patterns in the results might allow the development of guidelines for assigning species to threat categories, based on a combination of life history parameters, characteristics of the landscapes in which they live, and projected range changes. [source] Potential changes in the distributions of latitudinally restricted Australian butterfly species in response to climate changeGLOBAL CHANGE BIOLOGY, Issue 10 2002Linda J. Beaumont Abstract This study assessed potential changes in the distributions of Australian butterfly species in response to global warming. The bioclimatic program, BIOCLIM, was used to determine the current climatic ranges of 77 butterfly species restricted to Australia. We found that the majority of these species had fairly wide climatic ranges in comparison to other taxa, with only 8% of butterfly species having a mean annual temperature range spanning less than 3 °C. The potential changes in the distributions of 24 butterfly species under four climate change scenarios for 2050 were also modelled using BIOCLIM. Results suggested that even species with currently wide climatic ranges may still be vulnerable to climate change; under a very conservative climate change scenario (with a temperature increase of 0.8,1.4 °C by 2050) 88% of species distributions decreased, and 54% of species distributions decreased by at least 20%. Under an extreme scenario (temperature increase of 2.1,3.9 °C by 2050) 92% of species distributions decreased, and 83% of species distributions decreased by at least 50%. Furthermore, the proportion of the current range that was contained within the predicted range decreased from an average of 63% under a very conservative scenario to less than 22% under the most extreme scenario. By assessing the climatic ranges that species are currently exposed to, the extent of potential changes in distributions in response to climate change and details of their life histories, we identified species whose characteristics may make them particularly vulnerable to climate change in the future. [source] Marine range shifts and species introductions: comparative spread rates and community impactsGLOBAL ECOLOGY, Issue 3 2010Cascade J. B. Sorte ABSTRACT Aim, Shifts in species ranges are a predicted and realized effect of global climate change; however, few studies have addressed the rates and consequence of such shifts, particularly in marine systems. Given ecological similarities between shifting and introduced species, we examined how our understanding of range shifts may be informed by the more established study of non-native species introductions. Location, Marine systems world-wide. Methods, Database and citation searches were used to identify 129 marine species experiencing range shifts and to determine spread rates and impacts on recipient communities. Analyses of spread rates were based on studies for which post-establishment spread was reported in linear distance. The sizes of the effects of community impacts of shifting species were compared with those of functionally similar introduced species having ecologically similar impacts. Results, Our review and meta-analyses revealed that: (1) 75% of the range shifts found through the database search were in the poleward direction, consistent with climate change scenarios, (2) spread rates of range shifts were lower than those of introductions, (3) shifting species spread over an order of magnitude faster in marine than in terrestrial systems, and (4) directions of community effects were largely negative and magnitudes were often similar for shifters and introduced species; however, this comparison was limited by few data for range-shifting species. Main conclusions, Although marine range shifts are likely to proceed more slowly than marine introductions, the community-level effects could be as great, and in the same direction, as those of introduced species. Because it is well-established that introduced species are a primary threat to global biodiversity, it follows that, just like introductions, range shifts have the potential to seriously affect biological systems. In addition, given that ranges shift faster in marine than terrestrial environments, marine communities might be affected faster than terrestrial ones as species shift with climate change. Regardless of habitat, consideration of range shifts in the context of invasion biology can improve our understanding of what to expect from climate change-driven shifts as well as provide tools for formal assessment of risks to community structure and function. [source] Applying climatically associated species pools to the modelling of compositional change in tropical montane forestsGLOBAL ECOLOGY, Issue 2 2008Duncan J. Golicher ABSTRACT Aim, Predictive species distribution modelling is a useful tool for extracting the maximum amount of information from biological collections and floristic inventories. However, in many tropical regions records are only available from a small number of sites. This can limit the application of predictive modelling, particularly in the case of rare and endangered species. We aim to address this problem by developing a methodology for defining and mapping species pools associated with climatic variables in order to investigate potential species turnover and regional species loss under climate change scenarios combined with anthropogenic disturbance. Location, The study covered an area of 6800 km2 in the highlands of Chiapas, southern Mexico. Methods, We derived climatically associated species pools from floristic inventory data using multivariate analysis combined with spatially explicit discriminant analysis. We then produced predictive maps of the distribution of tree species pools using data derived from 451 inventory plots. After validating the predictive power of potential distributions against an independent historical data set consisting of 3105 botanical collections, we investigated potential changes in the distribution of tree species resulting from forest disturbance and climate change. Results, Two species pools, associated with moist and cool climatic conditions, were identified as being particularly threatened by both climate change and ongoing anthropogenic disturbance. A change in climate consistent with low-emission scenarios of general circulation models was shown to be sufficient to cause major changes in equilibrium forest composition within 50 years. The same species pools were also found to be suffering the fastest current rates of deforestation and internal forest disturbance. Disturbance and deforestation, in combination with climate change, threaten the regional distributions of five tree species listed as endangered by the IUCN. These include the endemic species Magnolia sharpii Miranda and Wimmeria montana Lundell. Eleven vulnerable species and 34 species requiring late successional conditions for their regeneration could also be threatened. Main conclusions, Climatically associated species pools can be derived from floristic inventory data available for tropical regions using methods based on multivariate analysis even when data limitations prevent effective application of individual species modelling. Potential consequences of climate change and anthropogenic disturbance on the species diversity of montane tropical forests in our study region are clearly demonstrated by the method. [source] Effects of drought on contrasting insect and plant species in the UK in the mid-1990sGLOBAL ECOLOGY, Issue 1 2002M. D. Morecroft Abstract Aim We examined the effects of drought in the summer of 1995 and the subsequent year on contrasting species of plants, moths, butterflies and ground beetles. We tested whether population increases were associated with: (a) species of warm environments (b) species of dry environments (c) species with rapid reproduction (d) species with high rates of dispersal. Location The study was conducted at Environmental Change Network (ECN) sites throughout Great Britain and Northern Ireland. Methods Climate monitoring, recording of plant species in permanent plots, transect walking for butterflies, light trapping for moths and pitfall trapping for carabid beetles were used. Results There was an overall increase in the number of species recorded in permanent vegetation plots between 1994 and 1996, principally among the annual and biennial vascular plants, probably as a result of gap colonization in grasslands. Most butterfly and moth species increased between 1994 and 1995. Among the butterflies, a southern distribution and high mobility were associated with species tending to increase throughout the period 1994,96, whereas declining species tended to have a northern distribution. A similar number of carabid beetle species increased as decreased in the period 1994,96; decreasing species tended to be associated with lower temperatures and wetter soils. Conclusions Current climate change scenarios indicate that the incidence of droughts in the United Kingdom will increase. A series of dry, hot summers could lead to a rapid change in the population of some species although others, including many plants, may be more resilient. This may lead to complex changes in ecosystems and needs to be considered in planning conservation strategies. [source] IHMS,Integrated Hydrological Modelling System.HYDROLOGICAL PROCESSES, Issue 19 2010Part 2. Abstract The integrated hydrological modelling system, IHMS, has been described in detail in Part 1 of this paper. The system comprises three models: Distributed Catchment Scale Model (DiCaSM), MODFLOW (v96 and v2000) and SWI. The DiCaSM simulates different components of the unsaturated zone water balance, including groundwater recharge. The recharge output from DiCaSM is used as input to the saturated zone model MODFLOW, which subsequently calculates groundwater flows and head distributions. The main objectives of this paper are: (1) to show the way more accurate predictions of groundwater levels in two Cyprus catchments can be obtained using improved estimates of groundwater recharge from the catchment water balance, and (2) to demonstrate the interface utility that simulates communication between unsaturated and saturated zone models and allows the transmission of data between the two models at the required spatial and temporal scales. The linked models can be used to predict the impact of future climate change on surface and groundwater resources and to estimate the future water supply shortfall in the island up to 2050. The DiCaSM unsaturated zone model was successfully calibrated and validated against stream flows with reasonable values for goodness of fit as shown by the Nash-Sutcliffe criterion. Groundwater recharge obtained from the successful tests was applied at various spatial and temporal scales to the Kouris and Akrotiri catchments in Cyprus. These recharge values produced good estimates of groundwater levels in both catchments. Once calibrated, the model was run using a number of possible future climate change scenarios. The results showed that by 2050, groundwater and surface water supplies would decrease by 35% and 24% for Kouris and 20% and 17% for Akrotiri, respectively. The gap between water supply and demand showed a linear increase with time. The results suggest that IHMS can be used as an effective tool for water authorities and decision makers to help balance demand and supply on the island. Copyright © 2010 John Wiley & Sons, Ltd. [source] Assessing the results of scenarios of climate and land use changes on the hydrology of an Italian catchment: modelling studyHYDROLOGICAL PROCESSES, Issue 19 2010Daniela R. D'Agostino Abstract Hydrological models are recognized as valid scientific tools to study water quantity and quality and provide support for the integrated management and planning of water resources at different scales. In common with many catchments in the Mediterranean, the study catchment has many problems such as the increasing gap between water demand and supply, water quality deterioration, scarcity of available data, lack of measurements and specific information. The application of hydrological models to investigate hydrological processes in this type of catchments is of particular relevance for water planning strategies to address the possible impact of climate and land use changes on water resources. The distributed catchment scale model (DiCaSM) was selected to study the impact of climate and land use changes on the hydrological cycle and the water balance components in the Apulia region, southern Italy, specifically in the Candelaro catchment (1780 km2). The results obtained from this investigation proved the ability of DiCaSM to quantify the different components of the catchment water balance and to successfully simulate the stream flows. In addition, the model was run with the climate change scenarios for southern Italy, i.e. reduced winter rainfall by 5,10%, reduced summer rainfall by 15,20%, winter temperature rise by 1·25,1·5 °C and summer temperature rise by 1·5,1·75 °C. The results indicated that by 2050, groundwater recharge in the Candelaro catchment would decrease by 21,31% and stream flows by 16,23%. The model results also showed that the projected durum wheat yield up to 2050 is likely to decrease between 2·2% and 10·4% due to the future reduction in rainfall and increase in temperature. In the current study, the reliability of the DiCaSM was assessed when applied to the Candelaro catchment; those parameters that may cause uncertainty in model output were investigated using a generalized likelihood uncertainty estimation (GLUE) methodology. The results showed that DiCaSM provided a small level of uncertainty and subsequently, a higher confidence level. Copyright © 2010 John Wiley & Sons, Ltd. [source] Validation of hydrological models for climate scenario simulation: the case of Saguenay watershed in QuebecHYDROLOGICAL PROCESSES, Issue 23 2007Yonas B. Dibike Abstract This paper presents the results of an investigation into the problems associated with using downscaled meteorological data for hydrological simulations of climate scenarios. The influence of both the hydrological models and the meteorological inputs driving these models on climate scenario simulation studies are investigated. A regression-based statistical tool (SDSM) is used to downscale the daily precipitation and temperature data based on climate predictors derived from the Canadian global climate model (CGCM1), and two types of hydrological model, namely the physically based watershed model WatFlood and the lumped-conceptual modelling system HBV-96, are used to simulate the flow regimes in the major rivers of the Saguenay watershed in Quebec. The models are validated with meteorological inputs from both the historical records and the statistically downscaled outputs. Although the two hydrological models demonstrated satisfactory performances in simulating stream flows in most of the rivers when provided with historic precipitation and temperature records, both performed less well and responded differently when provided with downscaled precipitation and temperature data. By demonstrating the problems in accurately simulating river flows based on downscaled data for the current climate, we discuss the difficulties associated with downscaling and hydrological models used in estimating the possible hydrological impact of climate change scenarios. Copyright © 2007 John Wiley & Sons, Ltd. [source] A review of climate risk information for adaptation and development planningINTERNATIONAL JOURNAL OF CLIMATOLOGY, Issue 9 2009R. L. Wilby Abstract Although the use of climate scenarios for impact assessment has grown steadily since the 1990s, uptake of such information for adaptation is lagging by nearly a decade in terms of scientific output. Nonetheless, integration of climate risk information in development planning is now a priority for donor agencies because of the need to prepare for climate change impacts across different sectors and countries. This urgency stems from concerns that progress made against Millennium Development Goals (MDGs) could be threatened by anthropogenic climate change beyond 2015. Up to this time the human signal, though detectable and growing, will be a relatively small component of climate variability and change. This implies the need for a twin-track approach: on the one hand, vulnerability assessments of social and economic strategies for coping with present climate extremes and variability, and, on the other hand, development of climate forecast tools and scenarios to evaluate sector-specific, incremental changes in risk over the next few decades. This review starts by describing the climate outlook for the next couple of decades and the implications for adaptation assessments. We then review ways in which climate risk information is already being used in adaptation assessments and evaluate the strengths and weaknesses of three groups of techniques. Next we identify knowledge gaps and opportunities for improving the production and uptake of climate risk information for the 2020s. We assert that climate change scenarios can meet some, but not all, of the needs of adaptation planning. Even then, the choice of scenario technique must be matched to the intended application, taking into account local constraints of time, resources, human capacity and supporting infrastructure. We also show that much greater attention should be given to improving and critiquing models used for climate impact assessment, as standard practice. Finally, we highlight the over-arching need for the scientific community to provide more information and guidance on adapting to the risks of climate variability and change over nearer time horizons (i.e. the 2020s). Although the focus of the review is on information provision and uptake in developing regions, it is clear that many developed countries are facing the same challenges. Copyright © 2009 Royal Meteorological Society [source] Statistical downscaling of extremes of daily precipitation and temperature and construction of their future scenariosINTERNATIONAL JOURNAL OF CLIMATOLOGY, Issue 5 2008Yeshewatesfa Hundecha Abstract Two statistical downscaling methods have been tested in terms of their ability to construct indices of extremes of daily precipitation and temperatures from large-scale atmospheric variables with the aim of developing a tool for the construction of future scenarios of the extremes. One of the methods implements an approach for constructing seasonal indices of extremes of precipitation and temperature from seasonal measures of large-scale variables, while the other method implements a stochastic model for generating daily series of precipitation and temperature whose parameters are conditioned on large-scale circulation patterns. While both models generally tend to perform fairly well in reproducing indices of precipitation in winter, their performance for the summer season is not attractive. For indices of temperature, the performance of both models is better than the corresponding performance for indices of precipitation and the seasonal variation in performance is less prominent. The models were applied to construct scenarios of the extremes for the end of the 21st century using predictor sets simulated by the Hadley Centre GCM (HadAM3P) forced by two of the special report on emission scenarios (SRES) emission scenarios. Both models project an increase in both the mean daily minimum and mean daily maximum temperatures for future climate change scenarios in all seasons. The summer increase is accompanied by an increase in the inter-annual variability of the temperatures. On the other hand, they show consistency in the direction of the projected changes in indices of precipitation only in winter, where they projected an increase in both the magnitude and frequency of extremes as well as the mean precipitation. The disparity in the changes simulated by the two models revealed the existence of considerable inter-model uncertainty in predicting changes for future climate. Copyright © 2007 Royal Meteorological Society [source] | |||||||||||||||||||||||||||||||||||||