New evidence of glacier surges in the Central Andes of Argentina and Chile

FALASCHI, DANIEL; BOLCH, TOBIAS; LENZANO, MARÍA G.; TAKEO ; LENZANO, LUIS

PROGRESS IN PHYSICAL GEOGRAPHY

SAGE PUBLICATIONS LTD

Lugar: London; Año: 2018

0309-1333

In contrast to the large surge-type glacier clusters widely known for several mountain ranges around the world, the presence of surging glaciers in the Andes has been historically seen as marginal. Based on the analysis of 1962-2015 satellite imagery, historical aerial images DEM differencing and literature survey, we identified 21 surge-type glaciers in the Central Andes of Argentina and Chile (32° 40´ - 34° 20 S). 11 surge events and six possible surge-type glaciers are here identified and described for the first time. The estimation of annual elevation changes of these glaciers for the 2000-2011 period, which encompasses the latest surge events in the region, showed heterogeneous behavior with strongly negative to positive patterns (-1.1 ? 1.0 m yr-1). Additionally, we calculated maximum surface velocities of 3 ±1.9 m d-1 and 3.8 ±1.1 m d-1 for the Piquenes and Noreste del Cerro Alto glaciers during the latest identifiable surge events of 1985-1987 and 2003-2007. Within this glacier cluster, highly variable advance rates, dissimilar surface velocities at the surge peak and heterogeneous duration of the surge cycles were observed.