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Climate change: Vulnerability, impacts, and adaptations |
| [180] | Genetic shift in photoperiodic response correlated with global warming | | Bradshaw WE and Holzapfel CM. 2001 | To date, all altered patterns of seasonal interactions observed in insects, birds, amphibians, and plants associated with global warming during the latter half of the 20th century are explicable as variable expressions of plastic phenotypes. Over the last 30 years, the genetically controlled photoperiodic response of the pitcher-plant mosquito, Wyeomyia smithii, has shifted toward shorter, more southern daylengths as growing seasons have become longer. This shift is detectable over a time interval as short as five years. Faster evolutionary response has occurred in northern populations where selection is stronger and genetic variation greater than in southern populations. W. smithii represents an example of actual genetic differentiation of a seasonal trait that is consistent with an adaptive evolutionary response to recent global warming.
(2 figures, 1 table, 29 references) | | Proceedings of the National Academy of Sciences of the United States of America98(25):14509–14511 | Ecology and Evolution Program,
Department of Biology, University of Oregon, Eugene, OR 97403–1210, USA
<wyomya@aol.com> | | | [181] | Climate change impact: regional scenario | | De US. 2001 | Climate change and global warming are going to be the major issues of the 21st century. Their impacts on agriculture, water availability, and other natural resources are of serious concern. The paper briefly summarizes the existing information on global warming, past climatic anomalies and occurrence of extreme events vis-à-vis their impact on south Asia in general, and India in particular. Use of GCM models in conjunction with crop simulation models for impact assessment in agriculture are briefly touched upon. The impact on hydrosphere (in terms of water availability) and on the forests in India, are also discussed. A major shift in our policy makers paradigm is needed to make development sustainable, in the face of climate change, global warming, and sea-level rise.
(4 figures, 2 tables, 54 references) | | Mausam52(1):201–212 | India Meteorological Department,
Pune-411 005, India | | | [182] | Climate change and the resurgence of malaria in the East African highlands | | Hay SI, Cox J, Rogers DJ, Randolph SE, et al. 2001 | The public health and economic consequences of Plasmodium falciparum malaria are once again regarded as priorities for global development. There has been much speculation on whether anthropogenic climate change is exacerbating the malaria problem, especially in areas of high altitude where P. falciparum transmission is limited by low temperature. The IPCC (Intergovernmental Panel on Climate Change) has concluded that there is likely to be a net extension in the distribution of malaria and an increase in incidence within this range. The authors investigated long-term meteorological trends in four high-altitude sites in East Africa, where increases in malaria have been reported in the past two decades. Here the authors show that temperature, rainfall, vapour pressure, and the number of months suitable for P. falciparum transmission have not changed significantly during the past century or during the period of reported malaria resurgence. A high degree of temporal and spatial variation in the climate of East Africa further suggests that claimed associations between local malaria resurgence and regional changes in climate are over simplistic.
(3 figures, 3 tables, 27 references). | | Nature415(6874):905–909 | TALA Research Group,
Department of Zoology, University of Oxford, South Parks Road, Oxford OX1 3PS, UK | | | [183] | Techniques for estimating uncertainty in climate change scenarios and impact studies | | Katz RW. 2001 | In this paper, the methodology for quantifying uncertainty in global climate change studies is reviewed. The focus is on recent developments in statistics, such as hierarchical modelling and Markov chain Monte Carlo simulation techniques, that could enable more full-fledged uncertainty analyses to be performed as part of integrated assessments of climate change and its impacts. First an overview of uncertainty analysis, including its sources and how it propagates, is provided. Presently employed techniques in climate change assessments, such as sensitivity, scenario, and Monte Carlo simulation analyses, are then surveyed. Next, alternative approaches, based on more formal statistical theory (especially the Bayesian statistical paradigm), are described. Finally, some tentative recommendations on strategies for achieving the goal of more reliably quantifying uncertainty in global climate change are made. One of the main points that comes out of this review is that uncertainty analysis should not be viewed as a minor component that can be 'added on' once a model has been developed. Instead, its consideration should be an integral part of the development of any model.
(3 figures, 3 tables, 100 references) | | Climate Research20(2):167–185 | Environmental and Societal Impacts Group,
National Center for Atmospheric Research, Boulder, Colorado 80307, USA
<rwk@ucar.edu> | | | [184] | Socio-economic impacts of climate change on Indian agriculture | | Kumar KSK and Parikh J. 2001 | Analysis of the impacts of climate change on agriculture, in India, is an important exercise, as it deals with the food security of more than a billion people. This study uses an integrated modelling framework to assess the socio-economic impacts of climate change on Indian agriculture. A crop simulation model is used to estimate the yield changes under various climate change scenarios for two main cereal crops: rice and wheat. Aggregated crop yield changes are then introduced as gradually occurring supply shocks to the economy in an applied general equilibrium model, and the socio-economic impacts of climate change are assessed. The results indicate that the projected large-scale changes in the climate would lead to significant reductions in crop yields, which in turn would adversely affect agricultural production. The economic and welfare impacts, captured through changes in indicators, such as value added and calorie intake, show that climate change would place significant burden on the economy. The results also show that people in the poorer sections of the population are likely to bear a greater share of the burden imposed by climate change. Consideration of carbon fertilization effects resulted in reducing the adverse impacts to some extent. The study also discusses the role of various policies in mitigating the negative impacts of climate change.
(2 figures, 5 tables, 26 references) | | International Review for Environmental Strategies2(2):277–293 | Madras School of Economics,
Gandhi Mandapam Road, Chennai - 600 025, India
<kavik@vsnl.net> | | | [185] | Regional aspects of global climate change simulations: validation and assessment of climate response over Indian monsoon region to transient increase of greenhouse gases and sulfate aerosols | | Kumar KR and Ashrit RG. 2001 | The regional climatic impacts associated with global climatic change and their assessment are very important since agriculture, water resources, ecology etc., are all vulnerable to climatic changes on a regional scale. Coupled AOGCM (atmosphere-ocean general circulation model) simulations provide a range of scenarios, which can be used, for the assessment of impacts and development of adaptive or mitigative strategies. Validation of the models against the observations and establishing the sensitivity to climate change forcing are essential before the model projections are used for assessment of possible impacts. Moreover, model simulated climate projections are often of coarse resolution while the models used for impact assessment, (e.g. crop simulation models, or river runoff models etc.) operate on a higher spatial resolution. This spatial mismatch can be overcome by adopting an appropriate strategy of downscaling the GCM (general circulation model) output. This study examines two AOGCMs - ECHAM4/OPYC3 and HadCM2 - climate change simulations for their performance in the simulation of monsoon climate over India and the sensitivity of the simulated monsoon climate to transient changes in the atmospheric concentrations of GHG and sulphate aerosols. The results show that the two models simulate the gross features of climate over India reasonably well. However, the inter-model differences in simulations of mean characteristics, sensitivity to forcing and in the simulations of climate change suggest need for caution. Further an empirical downscaling approach is used to assess the possibility of using GCM projects for preparation of regional climate change scenario for India.
(10 figures, 1 table, 25 references) | | Mausam52(1):229–244 | Indian Institute of Tropical Meteorology,
Dr Homi Bhaba Road, Pune - 411 008, India | | | [186] | Future climate change and its impacts over small island states | | Lal M, Harasawa H, and Takahashi K. 2001 | This paper examines the response of the climate of SIS (Small Island States) to transient increases in anthropogenic radiative forcing due to increases in atmospheric concentrations of greenhouse gases and/or sulfate aerosols using the data generated in a set of numerical experiments performed with a range of coupled A-OGCMs (atmosphere-ocean global climate models). Five of the 7 models considered in our validation exercise are found to have fair skill as regards their ability to simulate the broad features of present-day observed surface climatological features over the SIS in the Indian Ocean, the Mediterranean Sea, the Atlantic Ocean, and the Pacific Ocean. The transient experiments with these models, which include the time-varying future anthropogenic radiative forcings, have been used here to develop regional projections of future climate change. An area-averaged annual mean warming of ca 2 °C or higher for the 2050s and ca 3 °C or higher for the 2080s are projected for the SIS as a consequence of increases in atmospheric concentration of greenhouse gases. In general, seasonal variations of the projected surface warming over the SIS are minimal. No significant change in diurnal temperature range is likely with an increase in surface temperatures. An increase in mean temperature would be accompanied by an increase in the frequency of extremely high temperatures. The aerosol forcing will only marginally reduce the surface warming. The models simulate only a marginal change (<10%) in annual mean rainfall over most of the SIS. During the northern hemisphere summer, however, rainfall is projected to decline (except over Pacific Ocean islands). An increase in daily rainfall intensity leading to more heavy rainfall events is also projected. The projected changes in temperature and rainfall could disrupt the terrestrial and marine ecosystems in most SIS. An integrated study of vulnerability assessment for SIS based on a better understanding of the precise magnitude of increase in surface air temperature and associated sea-level rise is warranted for developing appropriate adaptation strategies.
(10 figures, 3 tables, 48 references) | | Climate Research19(3):179–192 | Centre for Atmospheric Sciences,
Indian Institute of Technology, Hauz Khas, New Delhi -110 016, India
<lal321@hotmail.com > | | | [187] | Increasing risk of great floods in a changing climate | | Milly PCD, Wetherald RT, Dunne KA, Delworth TL. 2001 | Radiative effects of anthropogenic changes in atmospheric composition are expected to cause climatic changes, in particular an intensification of the global water cycle with a consequent increase in flood risk. But the detection of anthropogenically forced changes in flooding is difficult because of the substantial natural variability; the dependence of streamflow trends on flow regime further complicates the issue. Here the authors investigate the changes in risk of great floods - that is, floods with discharges exceeding 100-year levels from basis larger than 200 000 km2 - using both streamflow measurements and numerical simulations of the anthropogenic climate change associated with greenhouse gases and direct radiative effects of sulphate aerosols. The authors find that the frequency of great floods increased substantially during the 20th century. The recent emergence of a statistically significant positive trend in risk of great floods is consistent with results from the climate model, and the model suggests that the trend will continue.
(3 figures, 1 table, 14 references) | | Nature415(6871):514–517 | US Geological Survey,
GFDL/NOAA, PO Box 308, Princeton, New Jersey 08542, USA
<cmilly@usgs.gov> | | | [188] | Modelling the impact of climate change on rice production in India | | Rathore LS, Singh KK, Saseendran SA, Baxla AK. 2001 | The CERES-Rice crop simulation model, calibrated and validated for the varieties PR 106 in north-west India, IR 36 in central India, and Jaya in South India, is used for analysing the effect of climate change on rice productivity in the country. Plausible climate change scenario for the Indian subcontinent as expected by the middle of the next century taking into account the projected emissions of GHGs (green house gases) and sulphate aerosols, in a coupled atmosphere ocean model experiment performed at Deutsches Klimarechenzentrum, Germany, is adopted for the study. The adopted scenario represented an increase in monsoon seasonal mean surface temperature of the order of about 1.5 °C over south India and 1 °C over North-West and Central India in the decade 2040-49 with respect to the 1980s, and an increase in rainfall of the order of 2 mm per day over south India while the simulated decrease of the order about — 1 mm and — 1.5 mm over North-West and Central India respectively. The IPCC business-as-usual scenario projection of plant usable concentration of CO2 about 460 PPM (parts per million) by the middle of the next century are also used in the crop model simulation (CERES-Rice V3 Model).
(4 figures, 3 tables, 44 references) | | Mausam52(1):263–274 | National Centre for Medium Range Weather Forecasting,
Department of Science and Technology, Mausam Bhawan, Lodhi Road, New Delhi-110 003, India | |
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