Rapid Grounding Line Retreat in Key Regions of Antarctica

PNAS Earth, Atmospheric, and Planetary Sciences, 2 March 2026

Satellite radar observations from 1992-2025 show concentrated areas of rapid retreat of the “grounding line,” where where this massive ice sheet meets the ocean floor. These regions include Wilkes and George V Lands in East Antarctica; the Bellingshausen Sea, Amundsen Sea, and Getz Ice Shelf sectors of West Antarctica, and the northeast and southwest Antarctic Peninsula. The most extreme retreat occurred in West Antarctica’s Amundsen and Getz sectors, where grounding lines retreated up to 42 kilometers at Smith Glacier, 33 kilometers at Pine Island Glacier, and 26 kilometers at Thwaites Glacier. Areas experiencing the greatest retreat have deep seafloor troughs that channel warm ocean water toward grounding zones, particularly where the bed slopes downward inland; raising concerns for more rapid future ice loss. As a whole, Antarctica lost over 12,000 square kilometers of grounded ice between 1996 and 2025, with 62% of the loss occurring in West Antarctica and 28% in East Antarctica. About 77% of the Antarctic grounding line otherwise has remained stable over this period.

Paper | Summary by the European Space Agency