Suchergebnisse

In September 1983, IIASA and UNEP, together with the Austrian Government, gave support to an International Study Conference on The Sensitivity of Ecosystems and Society to Climatic Change, which was attended by scientists from 17 countries. The conference was divided into two parallel workshops - on climate impacts in cold and in semiarid regions. This report brings together eight papers that ultimately arose from discussions in the "cold" workshop. In most cases they report the results of preliminary experiments relating to climatic change, and represent the outcome of a piece of "pilot" research by IIASA for UNEP to test the research methodology before applying it in a wider context. Of the variety of techniques and concepts applied, two deserve mention here. The first is the mapping of impact areas by the spatial shift of isopleths or boundaries. The second is the construction of a hierarchy of climate, impact, and economic models to trace the cascade of climate impacts through biophysical, economic, and social systems. This report marks the completion of IIASA's pilot study. The full research project, funded jointly by UNEP and IIASA, is now being implemented in 12 case studies through a collaborative network of 70 scientists. Its purpose is to evaluate the impact of climatic change and variability on food production in climate-sensitive areas, and to consider appropriate policies of mitigation.

This article first introduces the correlation between volcanism and global climatic abnormalities (commonly referred to as global cooling), with particular reference to the Tambora eruption in 1815. Recent case studies in China concerning this volcanic effect and climate changes in the nineteenth century are brought in to substantialize and revise some general statements previously made about China. These case studies cover various regions, including the Yangzi Delta, Yunnan, the Jiaodong Peninsula, and the North China Sea area, and examine a wide range of topics such as floods, famines, economic recession, crop patterns (including those of New World crops), and Pacific herring catches. Finally, this article provides suggestions for future studies of the Tambora effects in China and proposes to bring climate into the specific temporal span of the decline of the Qing Empire.

ABSTRACTMuch has been written in recent years about the potential threats posed by increasing greenhouse gas concentrations. This paper summarizes the implications of global warming for hydrological processes in general and river flow characteristics in the UK in particular, emphasizing the present high degree of uncertainty. Current climate change scenarios for the UK imply that rainfall between autumn and spring will increase, and this may have beneficial implications for UK water resources. However, the effect of this increase may be outweighed by higher evapotranspiration. Average annual runoff in a catchment in southern UK may be reduced by around 5% by the middle of the next century, but this estimate is very uncertain: runoff may reduce by 30% or increase by 30%. Runoff in northern and western UK is likely to show a slight increase (but with similarly large confidence intervals). It is probable that river flows in the UK will be much more concentrated in winter than at present. The effect of a given climate change scenario on monthly flow regimes depends on the current summer water balance and on catchment geological conditions.