EFFECTS OF CLIMATE-CHANGE ON WATER-RESOURCES AND RUNOFF IN AN ALPINE BASIN

The combined influence of increased temperatures and changed precipita tion on the seasonal snow cover and runoff is evaluated for the Upper Rhine Basin at Felsberg (3250 km(2), 560-3614 m a.s.l.). The runoff re gime reflects the snow accumulation in the winter half-year and snowme lt in the summer half-year. The method of predicting future runoff reg imes is based on high resolution periodical snow cover mapping by sate llites. The snow coverage is the main input variable for the snowmelt runoff model SRM-ETH (version of the Institute of Technology ETH). The model computes the present runoff and the climate-affected snow-cover ed areas, from which it computes the future runoff. Conditions of the present climate are represented by a normalized year. Snow conditions and yearly hydrographs are evaluated for the years 2030 and 2100 accor ding to the given climate scenarios for this region. Quantitative resu lts indicate the decrease of the snow accumulation on 1 April as well as the seasonal redistribution and changes of runoff. (C) 1998 John Wi ley & Sons, Ltd.