ABSTRACT
Most of the total discharge of the Rhône River at the mouth (1700 m3.s-1) originates in the Alps. Climatic models anticipate a decrease of total discharge, a marked decrease of summer discharge, an increase in winter discharge, and a decrease in ice and snow cover, inducing a change in the river fl ow regime. However, the high level of economic development in the entire watershed has triggered complex impacts on river and lake hydrosystems. These already registered changes foreshadow predicted changes and provide insights into the future of aquatic ecosystems that will suffer the impacts of warmer temperatures. An attempt was made to summarize the possible impacts on the future uses of water. Hydro and thermal power will be affected by changes in hydrological regime and reduction in the cooling capacity of the Rhône River. Also, tourism will experience a reduction of snow cover in winter; agriculture, a reduction of water availability in summer; human health will face threats of new kinds of parasites; and last, the level of fl ood risks may increase in valley bottoms following deposition of sediments and increased water levels.
