Inventory and recent changes of small glaciers on the northeast margin of the South Patagonian Icefield, Argentina

MASIOKAS, M.H.; DELGADO, SILVIA; BERTHIER, E.; PITTE, P.; RUIZ, LUCAS; VILLALBA, RICARDO

Uspallata

Workshop; IAI CRN 2047B. Documenting Understanding and projecting changes in the hydrological cycle in the American Cordillera; 2013

IAI, IANIGLA-CONICET

Most glacier studies in southern Argentina have focused on the large outlet glaciers of the South Patagonian Icefield (SPI) and the numerous smaller neighboring glaciers have received significantly less attention. Here we present the glacier inventory of two relatively small basins that are adjacent to the northeast margin of the SPI. Glacier outlines were mapped using the only cloud-free 15-m resolution ASTER scene available for late summer, 2005 (20 February) and glacier morphometric data (hipsometry, orientation and slope) were derived from the ASTER Global Digital Elevation Model v.2. These basins contain 246 small ice masses ranging between 0.01 and 25 km2 in size and covering a total area of 187 km2 distributed between 600 and 2870 m in elevation. The glacierized area is mostly oriented towards the SE, and the transient snow line was identified at 1600 ± 160 m in 2005. Glaciers were also mapped on a recently declassified, late summer 1979 U.S. spy satellite photograph (ca. 7 m pixel resolution) from the same region. We will discuss the total areal reduction between 1979 and 2005 and assess these changes in terms of glacier size, elevation and orientation. An attempt will be made to relate the changes observed in the glacierized area with local changes in climate data. The results constitute a new addition to the ongoing National Glacier Inventory project in Argentina and have been submitted to the Global Land Ice Measurements from Space (GLIMS) database. They are the first Argentinean contribution to this international program.