INSTITUTO ARGENTINO DE NIVOLOGIA, GLACIOLOGIA Y CIENCIAS AMBIENTALES
Unidad Ejecutora - UE
capítulos de libros
Glacier retreat in the Central Andes of Argentina
ESPIZUA, LYDIA E.; MALDONADO, GABRIELA; PITTE, PIERRE
Water Sustainabelity. A Global Perspective International Geographical Union Commission for Water Sustainability.
Hodder Education, An Hachette UK Company
Lugar: Londres; Año: 2010; p. 2 - 452
Glaciers in the Central Cordillera of the Andes in Argentina show marked retreat since the late nineteenth century (Figure 12.8). The glaciers provide 'natural regulation' for the rivers draining from the mountains. This is critical for maintaining water supply in the semi-arid regions east of the mountains, where precipitation is limited by the Andes, which act as a barrier for most of the humidity coming from the Pacific Ocean on the westerly winds. Loss of the glaciers would be a severe blow for agriculture, viticulture and many cities in the region. The fluctuations of the Las Vacas, Güssfeldt, EI Azufre and EI Peñón glaciers in Mendoza Province have been studied from the late nineteenth century to 2007, through historical records, topographic maps, aerial photographs (from 1963 and 1974). Recent images from the Landsat satellite (Figures 12.9 and 12.10), and measurements in the field using Global Positioning (GPS). Satellite remote sensing is a useful tool for studying glacier fluctuations because the areas are often inaccessible. The Las Vacas and Güssfeldt glaciers are large glaciers (between 5 and 10 km long) and EI Azufre and EI Peñón are medium-sized glaciers (between 1 and 5 km long), all flowing toward the east Figures 12.8 to 12.10 show that there is a clear, overall retreating trend from 1894/6 to 2007. The Las Vacas glacier showed a marked retreat from 1896 to 1963, and a lesser one between 1963 and 1974. The glacier advanced in 1974-2003, then remained stationary, and has retreated slightly since then. The Güssfeldt glacier retreated dramatically between 1896 and 1987, continued retreating slightly between 1987 and 1ggg and remained stationary in 2004 and 2007. Large glaciers like these give strong, smoothed signals of trends with a delay of several decades. The EI Azufre and EI Peñón glaciers also underwent a general retreat over the period (Figures 12.8 and 12.10). Both display simultaneous fluctuations with very marked retreats (1894/1897-1963 and 1990-2004), advances (1 963-1 986), and a near stationary period (1 986-1990). The glaciers advanced slightly during 2004-2007. The advance of Las Vacas, EI Azufre and EI Peñón glaciers during the 1980s and 1990s could be related with the strong ENSO events of 1982-1983, 1986-1987 and 1997-1998.