Glaciers in the Andes in climate change:
The ice loss rates of glaciers in the Andes are among the highest in the world, and contribute about 0.05 to 0.06 mm per year to global sea-level rise. The ice masses of the Andes extend throughout different altitude ranges and climate zones, from tropical climate conditions in the north to the sub-polar climate of Tierra del Fuego at the southern tip of the continent. This leads to a highly heterogeneous morphology of glacier types, from ice caps on volcanoes and small cirque and valley glaciers in the high altitudes of the tropics and the Central Andes, to calving outlet glaciers at the ice fields of Patagonia of several tens of kilometers in length. Global climate change is also strongly affecting the Andes. As in most regions of the world, significant temperature changes have been recorded in the last century, which show distinct spatio-temporal variations. Particularly at high altitudes, there has been a rapid rise in temperature, like in the Cordillera Blanca in Peru. Consequently, a large-scale retreat of the glaciers along the Andes has been observed. Especially noteworthy are the heavy area losses at the glaciers of the Tropical Andes as well as the retreat and high mass losses of glaciers of the large Patagonian Ice Fields. Projections of the glacier evolution along the Andes assume an almost complete disappearance of the ice masses in the Tropical Andes until the end of the 21st century, significant retreat of the glaciers in the Central Andes and further high ice losses in Patagonia and Tierra del Fuego. In many tropical and semi-arid areas, glaciers pose a fundamental water resource. The loss of glaciers as a water resource, especially during the dry season and drought periods, is expected to have strong socio-economic impacts. Furthermore, glacier retreat increases the risk of so-called glacier lake outburst floods, which have already led to high casualties and economic losses in the past. Therefore, monitoring of glacier changes along the Andes is of central importance from a scientific point of view as well as a source of information for future water resource and natural hazard management.