Climate change

About: Climate change is a research topic. Over the lifetime, 99222 publications have been published within this topic receiving 3572006 citations.

Extinction debt of high-mountain plants under twenty-first-century climate change

Abstract: Quantitative estimates of the range loss of mountain plants under climate change have so far mostly relied on static geographical projections of species’ habitat shifts 1‐3 . Here, we use a hybrid model 4 that combines such projections with simulations of demography and seed dispersal to forecast the climate-driven spatio-temporal dynamics of 150 highmountain plant species across the European Alps. This model predicts average range size reductions of 44‐50% by the end of the twenty-first century, which is similar to projections from the most ‘optimistic’ static model (49%). However, the hybrid model also indicates that population dynamics will lag behind climatic trends and that an average of 40% of the range still occupied at the end of the twenty-first century will have become climatically unsuitable for the respective species, creating an extinction debt 5,6 . Alarmingly, species endemic to the Alps seem to face the highest range losses. These results caution against optimistic conclusions from moderate range size reductions observed during the twenty-first century as they are likely to belie more severe longer-term effects of climate warming on mountain plants. Many plant and animal species have already been shifting their ranges in response to the past century’s climatic trends 79 . In mountains, owing to the altitudinal temperature gradient, species should primarily move upslope under warming, as has indeed been frequently documented during the recent decades 10,11 as well as in the palaeorecord 12,13 . As mountains usually have conical shapes, upslope movement inevitably results in range loss and may even lead to ‘mountain-top extinctions’ 14 in extreme cases. However, previous predictions of the magnitude of such range and biodiversity losses during the twenty-first century have been criticized 4,15 for relying on static ‘niche-based’ modelling approaches 16 , which disregard several processes crucial to range

Will U.S. Agriculture Really Benefit from Global Warming? Accounting for Irrigation in the Hedonic Approach

Abstract: Will U.S. Agriculture Really Benefit from Global Warming? Accounting for Irrigation in the Hedonic Approach. Wolfram Schlenker, W. Michael Hanemann, and Anthony C. Fisher ∗ There has been a lively debate about the potential impact of global climate change on U.S. agriculture. Most of the early agro-economic studies predict large damages (see, for example, Richard M. Adams, 1989; Harry M. Kaiser et al., 1993; and Adams et al., 1995). In an innovative paper Robert Mendelsohn, William D. Nordhaus and Daigee Shaw (1994) - hereafter MNS - propose a new approach: using the variation in temperature and precipitation across U.S. counties to estimate a reduced form hedonic equation with the value of farmland as the dependent variable. A change in temperature and/or precipitation is then associated with a change in farmland value which can be interpreted as the impact of climate change. Adams et al. (1998) characterize the hedonic approach as a spatial analogue approach, and acknowledge that ”the strength of the spatial analogue approach is that structural changes and farm responses are implicit in the analysis, freeing the analyst from the burden of estimating the effects of climate change on particular region-specific crops and farmer responses.” On the other hand, one of the potential disadvantages of the hedonic approach is that it is a partial equilibrium analysis, i.e., agricultural prices are assumed to remain constant. 1 While year-to-year fluctuations in annual weather conditions certainly have the potential to impact current commodity prices, especially for crops produced only in a relatively localized area, (such as citrus fruits which are grown mainly in California and Florida), changes in long-run weather patterns (i.e., changes in climate) might have a smaller effect on commodity prices because of the greater potential for economic adaptation, particularly shifts in growing regions. 2 The hedonic approach as implemented by MNS predicts that existing agricultural land on average might be more productive and hence result in benefits for U.S. farmers. 3 The hedonic approach has received considerable attention in our judgment in part because the conclusions are at variance with those of some other studies

Climate Change and Human Health. Risks and Responses

Abstract: In 1996 a group of health researchers organized by WHO, the World Meteo-rological Organization (WMO), and the United Nations Environment Programme (UNEP) published the first comprehensive assessment of climate change and human health (1). Climate change and human health: risks and responses updates this work — and opens new pathways through which to exam-ine the consequences the future climate may hold for the ecological systems that underpin our health. As the rates of warming, CO

Heavier summer downpours with climate change revealed by weather forecast resolution model

Abstract: Changes in precipitation extremes are occurring under climate change, but how they will manifest on sub-daily timescales is uncertain. This study used a high-resolution model, typically used for weather forecasting, to simulate hourly rainfall in the UK in the year 2100. The results confirmed previous findings of winter rainfall intensification and found that short-duration rainfall intensified in summer, increasing the risk of flash flooding.