Abstract:

Observations of the Antarctic Ice Sheet in recent years have revealed rapid and substantial changes occurring on the ice sheet on relatively short time scales. The principal drainage systems of Amundsen Sea Sector in West Antarctic are thinning rapidly, and the pattern of thinning extends to the interior of up to 150 km. Ice Stream C has slowed down while the flow in some areas has changed direction in the Ross Sea Sector. Vast areas of the Antarctic Peninsula Ice Shelves have collapsed, resulting in the acceleration and surge of tributary glaciers. Basal melting near the grounding lines is substantially due to erosion of a warm ocean. These evidences lead to our view that the Antarctic Ice Sheet is slowly changing and homogeneous has radically altered. This finding has important consequences for the ice dynamic study, ice sheet modeling and the mass balance assessment and its response to climate forcing.