Decadal-scale variations in glacier area changes across the Southern Patagonian Icefield since the 1970s

Abstract

A combination of Landsat and ASTER satellite scenes are used to quantify changes in the areal extent of glaciers in 130 basins across the Southern Patagonian Icefield (SPI). There was extensive net overall loss, with a reduction in ice area of 542 km2 (∼4% of the SPI) between the late 1970s and 2008/2010. For glaciers measured within individual periods, average losses occurred at a rate of 3.24% decade-1 between 1976/1979 and 1984/1986, 2.04% decade-1 between 1984/1986 and 2000/2002, and 2.24% decade-1 between 2000/2002 and 2008/2010. This indicates sustained losses, but no evidence for a recent acceleration. Since the 1980s, glaciers located in the northwest part of the SPI experienced the highest mean annual loss rates at 2.9% decade-1. Mean glacier elevation provides the only significant topographic control on glacier changes for all measurement periods, and glacier losses are consistent with recent warming and changes in precipitation observed for this region.