Abstract
There are several indications that changes in land cover have influenced the hydrological regime of various river basins. In addition, the effects of climate change on the hydrological cycle and on the runoff behaviour of river catchments have been discussed extensively in recent years. However, it is at present rather uncertain how, how much and at which spatial scale these environmental changes are likely to affect the generation of storm runoff, and consequently the flood discharges of rivers. Firstly, this paper gives an overview of the possible effects of climatic and land‐use change on storm runoff generation. Secondly, it discusses models dealing with the hydrological response to climate and land‐use variations, including both the downscaling of climate information from global circulation models and the way flood forecasting models represent land‐use conditions. Finally, two modelling studies of meso‐scale catchments in Germany are presented: the first shows the possible impacts of climate change on storm runoff production, and the second the impacts of land‐use changes. Copyright © 2002 John Wiley & Sons, Ltd.