Big Ice

Antarctic Ice Shelf Change and Basal Melt Using ICESat, Cryosat, and Other Satellite Data

Summary

Deeply embayed ice shelves and narrower fringing ice shelves surround much of Antarctica. Recent results indicate that these ice shelves help regulate the flow of upstream glaciers and ice streams (“ice-shelf buttressing”). This investigation focuses on determining the mass balance of Antarctica’s non-Peninsula ice shelves and on improving our knowledge of the processes that control basal melt.

A major component of this investigation is determining the flow speed on all major ice shelves, which will be used to estimate melt rates. Thus far we have processed a large volume of RADARSAT data to map those ice shelves located between the Filchner-Ronne and Amery ice shelves. The high snowfall accumulation causes RADARSAT C-band image pairs to decorrelate rapidly, making it difficult or impossible to map flow velocities in the Amundsen Sea region. To overcome this limitation, we are acquiring and processing data from the ALOS L-Band PALSAR, which should yield more successful results. Once complete, we will combine these data with ice shelf thickness and rates of thickness changes to produce a comprehensive set of melt rate estimates.