Glaciers in the Chilean central Andes (Fig. 49.1, 32°S – 41°S) have shown significant frontal retreat, area shrinkage and ice thinning in an accelerating trend during recent decades, presumably in response to atmospheric warming and reduction of precipitation. Nearly 1600 glaciers with a total ice area of ca. 1300km2 have been inventoried in the Chilean central Andes, which have experienced a total volume loss due to thinning and retreat of 46 ± 17km3 of water equivalent between 1945 and 1996 (Rivera et al., 2002), affecting water resources availability for agriculture, mining and human consumption. This region includes the most populated part of the country (33°S–36°S) and its glaciers have been recognized as a key factor in contributing to late summer runoff in many of the main river basins, especially during summers with severe drought when up to 67% of the water flow is generated by glacier meltwater (Peña & Nazarala, 1987). In spite of the importance of the regional glaciers, very limited glaciological research has been carried out since the pioneering work of Lliboutry (1956). There are still some basins without glacier inventories, especially regarding debriscovered ice, very few ice-thickness data exist (Rivera et al., 2001) and very little is known about the energy and mass balance of the glaciers (Corripio, 2002).

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