Water experts at a conference in the Alpine ski resort of Megeve, in France's Department of Haute-Savoie, warned that melting caused by global warming and the increasing use of scarce water resources to create snow artificially at ski resorts were threatening Europe's mountain glaciers. The volume of snow in the Alps has dropped over the past 20 years and half of all French glaciers are expected to vanish by the end of the century, said meteorologists. The result will be dwindling supplies of freshwater for many countries, since, explained Director-General Jean-Francois Donzier of the International Office for Water, European rivers depend heavily upon runoff.