Climate change is no longer a matter of a distant future; it is already taking place all over the world, in Europe and also in Germany. Thus, an increase in the number of extreme weather events such as heat spells and floods is observed. For example, the Elbe flood in 2002 caused material damage amounting to more than 9 thousand million Euros; 18 persons lost their lives. A comparison of historical and current photographs depicting glaciers in the Alps gives evidence of their drastic shrinking during recent decades.