Synoptic to Seasonal Variability of Mountain Glacier surfaces in Patagonia and British Columbia/Alaska

B. Isacks, J. Ramage, S. Das		Dept. Geol. Sci., Cornell University, Ithaca, NY bli1 cornell.edu Cornell Geological Sciences
L. Smith		Dept. Geography, UCLA, Los Angeles, CA lsmith@geog.ucla.edu
R. Forster		Byrd Polar Institute, Ohio State Un., Columbus, OH forster@iceberg.mps.ohio-state.edu

Abstract

Outside of Greenland and Antarctica, the maritime, mid-latitude ice fields and glaciers of Southeast Alaska, British Columbia and Patagonia (southern Chilean/Argentine Andes) are among the world's largest and most active glacier systems in terms of mass flux. The rapid mass turnover, the respective locations in the northern and southern hemispheres, and the relative inaccessability of these areas make them particularly interesting in terms of their contributions to modern glacier recession and their reflections of global climate change. A key problem in understanding these two regions is the identification of the meteorological controls on mass balance and the changes in mass balance. The two regions offer interesting contrasts in climate regimes. While the North American areas appear to reflect typical mid-latitude seasonality in mass accumulation and ablation, the relative importance of seasonal versus synoptic weather systems in the Patagonian icefields and glaciers, subjected to the more oceanic regime of the mid-latitudinal Southern Hemisphere, remains a major question. We are addressing these problems through analyses of multi-temporal sequences of synthetic aperature radar images from the ERS-1 and ERS-2 satellites and the two SIR-C/X-SAR Shuttle missions. The SAR data is particularly effective in identifying snowmelt conditions. In conjunction with available meteorological data, we are determining the distribution of melting episodes over synoptic, seasonal and inter-annual time scales.

Keywords: mountain glaciers, glaciology, Alaska, British Columbia, Patagonia

Keywords: ESA European Space Agency - Agence spatiale europeenne, observation de la terre, earth observation, satellite remote sensing, teledetection, geophysique, altimetrie, radar, chimique atmospherique, geophysics, altimetry, radar, atmospheric chemistry