Regional Hydrological Impacts Of Climatic Change

This volume arises from the work of the International Geographical Union Working Group on Regional Hydrological Response to Climate Change and Global Warming under the chairmanship of Professor Changming Liu (1992-96). The book consists mostly of peer-reviewed papers delivered at the Working Group's first three scientific meetings held in Washington, D.C. (1992), Lhasa, Tibet (1993) and Moscow (1995). These have been supplemented by a few additional chapters that have been specifically commissioned in order to give a well-rounded coverage of the global and scientific aspects of the topic. As editors, we have sought to balance state-of-the-art reviews of methodology and regional research with detailed studies of specific countries and river basins. In the spirit of the IGU, we have devoted particular effort to encouraging contributions from scientists in the non-English-speaking world. These chapters provide valuable evidence of recent climatic change and predictions of future hydrological impacts from parts of the world where little detailed work has been conducted hitherto. They provide much valuable information that is new and interesting to an international audience and is otherwise very difficult or impossible to acquire. It is hoped that the present volume will be not only a record of current achievements, but also a stimulus to further hydrological research as the detail and spatial resolution of Global Climate Models improves. One notable aspect that emerges from a number of the contributions is that many, though by no means all, recent hydrological trends are in line with global warming predictions.

Examines the implications of possible climate changes and variability on both global and regional water resources.

year simulations in order to separate noise in the system from the climate change signal. Several contributing papers focused on case studies using Regional Climate Models (RCMs) linked to hydrological models, applied to the analysis of runoff under conditions of convective activity and extreme precipitation, in regions of complex topography, or stakeholder-driven investigations such as water runoff simulations in Quebec undertaken for a major utility. Thorough analyses of GCM results for the Century were reported at the Workshop, in order to illustrate the improvements in model results which have taken place in recent years, and the increasing confidence with which the models can be used for projecting climatic change in coming decades. However, there is still much room for improvement; there is also a need to address more fully the manner in which climate and impacts models (e. g. , hydrological models) can be linked, in terms of consistency and the overlap between different scales, the underlying physical assumptions, and the parameterizations used. Session 2 was devoted to the two extremes of water resources, namely floods and droughts, the focus here being to identify the climate change component in river floods. These have significant economic implications, as was shown by several scientists from Western and Central Europe. Many long time series have been studied worldwide with the aim of detection of nonstationarities, yet there is no conclusive evidence of climate-related changes in flow records, in general.

Cambridge, UK : Cambridge University Press, 1998.

This paper summarizes the methods and findings of the hydrological assessment component of the project studying likely impacts of climate change on water resources and agriculture in Africa. The first phase of the study used a version of a conceptual rainfall-runoff model called WatBal (Water Balance) applied to gridded data to simulate changes in soil moisture and runoff across the whole continent of Africa rather than to any particular catchment or water resource system. The model inputs were the climate variables of the 1961-90 climatology and physiological parameters (such as soil properties and land use) derived from global datasets for each of the 0.5 degree latitude/longitude cells across the continent. The primary model output comprised a time series (monthly time step) of simulated runoff for all the grid cells for each of the districts in the countries of interest. The second phase of the study extended the hydrology analyses to update the above hydroclimatic series to the year 2000 using updated input data. To ascertain the possible impacts of climate change within the districts being investigated this study used synthetic or GCM-based climate change scenarios as input to the WatBal model. The WatBal model was used to determine the impact of these different scenarios on runoff and actual evaporation and hence flow in the districts under study. The generated hydroclimatic series and scenario analyses were used as inputs into various Ricardian regressions in other analyses measuring likely impacts of climate change on the agricultural economies of Africa.