Antarctica has lost 5,000 square miles of grounded ice in 30 years

A satellite study finds Antarctica lost nearly 5,000 square miles of grounded ice from 1992 to 2025, and about 77% of the continent’s coastline showed no detectable grounding-line migration over the same period.

A new satellite analysis reports that Antarctica lost nearly 5,000 square miles (about 12,950 km²) of grounded ice between 1992 and 2025. The study maps grounding-line changes — the boundary where land-based ice begins to float — across the continent using three decades of observations. Researchers say much of the coastline remained stable, but some regions experienced notable retreat. The authors present the record as a testbed for computer models that project future sea level change. Key points: - The study reports nearly 5,000 square miles of grounded ice were lost over the 1992–2025 period. - About 77% of Antarctica’s coastline showed no detectable grounding-line migration since 1996. - Significant grounding-line retreat was observed in parts of West Antarctica, the Antarctic Peninsula, and sectors such as Getz and the Amundsen Sea. - The dataset is described as a real-world record for evaluating and validating models used to project future sea level changes; the research was published March 2 in Proceedings of the National Academy of Sciences. Summary: The observational record provides a 30-year baseline that researchers say models must reproduce to gain credibility for future sea level projections. Authors note that while much of Antarctica is currently stable, that balance may not hold indefinitely and the new record will be used to test model performance and improve understanding going forward.