"... As hydrological reservoirs, glaciers are seen by the public mainly for their contribution to , which they provide through their melting. This is admittedly of global interest and may change our planet in the long term, especially if the two ice sheets in Greenland and Antarctica are included. Somewhat less well known is the fact that glaciers are active landscape shapers and have in the past shaped not only high mountain relief but also large areas of North American and Central and Northern European lowlands. Anyone wishing to understand the formation of these glacial land surfaces cannot avoid considering the processes and effects of glacier erosion and deposition."