Impact of climate change on the discharge of the river rhine

Abstract Climate change influences the water balance of drainage basins in several ways. In a project of the International Commission for the Hydrology of the Rhine basin the possible consequences for the discharge regime of the Rhine are investigated. In the first phase of this project detailed models have been developed and applied for selected sub-basins and a simple water balance model has been developed for the whole Rhine basin. Results are presented for climate scenarios assuming an increase in temperature of about 3°C and an increase in annual precipitation. The consequences of such a climate change are largest in the Alpine part of the Rhine basin, and are also considerable in other parts of the basin and for the basin as a whole. In general the Rhine changes towards a rain-fed river. The winter discharge increases, which can have consequences for safety, and summer discharge decreases with consequences for shipping, industry, agriculture and ecology.