Recent changes in some glaciers of the Desert Andes (29º29'S) and its relationships with climate variations

PITTE, P.; ESPIZUA, L. E.; FERRI HIDALGO, L.; GARGANTINI, H.

Corvalis, USA

Conferencia; PAGES Open Science Meeting Retrospective Views on our Planet's Future; 2009

PAGES

Climatic conditions in the Desert Andes of Argentina (22ºS-31ºS) are generally unfavorable for glacier development. In the study area located at 29º20’S, the precipitation is low (245 mm water eq/year) and the year-round sun radiation is high (0.4 kw/m²). Inventory of 3 basins covering 80 km² indicate that glaciers are small in size (less than 1.5 km²), mainly south-east orientated (restricted to sun- and wind-shaded slopes), largely covered by penitents and showing little evidences of ice motion. Glaciers are reservoir type and snowline was observed at 5100-5200 m asl in 2005. A relevant feature of the study area is the presence of rock glaciers, that develop between the observed snowline and 4150 m asl. Previous work about glacier fluctuations in the area showed that between 1959 and 2005 most clean ice glaciers experienced little areal loss, but appear to have downwasted. Monitoring of glacier changes since 2005, with high resolution satellite images, under 1 m spatial resolution, showed area loss and other enhanced ablation evidence as high as 5100 m asl. Recent glacier variations are being compared with available temperature and precipitation data to explore the dominant controls of glacier changes.