Ice loss from the Southern Patagonian Ice Field, South America, between 2000 and 2012

Abstract

A time‐series composed of 156 ASTER derived Digital Elevation Models (DEMs) and a radar‐penetration‐bias corrected version of the Shuttle Radar Topography Mission (SRTM) DEM is used to derive ice surface height and volume changes at the Southern Patagonian Ice Field (SPI) in southern South America. The observations, made between February 2000 and March 2012, indicate that the ice field is rapidly losing volume at many of the largest outlet glaciers, and in most cases thinning extends to the highest elevations of the ice field. Mass loss is occurring at a rate of −20.0 ± 1.2 Gt a−1, which, when summed with mass‐loss at the adjacent Northern Patagonian Ice Field results in a combined rate of −24.4 ± 1.4 Gt a−1, equivalent to +0.067 ± 0.004 mm a−1of sea level rise. Our decade‐long mass loss rates are substantially higher than those derived during the last three decades of the 20th century, but are in good agreement with recent GRACE observations. Our volume loss estimate is sensitive to constraints applied to the amount of thickening in the accumulation zone. New field measurements and a continued DEM time‐series will be required to refine our estimates.