INSTITUTO ARGENTINO DE NIVOLOGIA, GLACIOLOGIA Y CIENCIAS AMBIENTALES
Unidad Ejecutora - UE
congresos y reuniones científicas
A preliminary glacier inventory for the Wet Andes between 42°S and 42°10S
LUCAS RUIZ; DARIO TROMBOTTO; RICARDO VILLALBA
Congreso; International Glaciological Coonference VICC 2010 "Ice and Climate Change": A View from the South; 2010
Abstract The study presented here describes two major tasks. First, a preliminary glacier inventory of the Wet Andes between 42°S, 72°10 W and 42°10 S, 72° W, was made. The study area is characterised by a small ice field, from which valley glaciers or hanging glaciers flow out. Similar ice fields exist further west. The inventory was compiled using one ASTER scene of 2007, following Global Land Ice Measurements from Space (GLIMS) methodology. Because of the presence of cloud cover, cast shadow parts and proglacial lakes, a manual correction of glacier boundaries was necessary. The total area covered by glaciers and/or snow patches is ~100 km2, with 103 glaciers larger than 0.1 km2 of which 50% have an area smaller than 0.5 km2. The largest glacier is the Esperanza Norte glacier which lies in Argentina with an area of 10.7 km2. Secondly, 3-dimensional glacier parameters obtained from a digital elevation model (ASTER_GDEM) in a GIS environment were compared to the horizontal area change between 1987 and 2007 in order to characterise the influence of topography in the response of glaciers to climate. The glacier extent in 1987 was obtained from Landsat TM imagery. As a preliminary result, glaciers that lost more area between 1987 and 2007 are characterised by an ablation zone of low gradient and low elevation, with most of them having developed proglacial lakes in the 20 year period. Another significant change is related to valley glaciers that now are reconstituted. This dynamic behavior has to be considered when evaluating the response of glaciers to climate.