Thwaites Glacier Could Contribute Twice as Much Sea-Level Rise as Previously Projected

Sea-level contribution from Thwaites Glacier doubles in an observation-constrained ice-sheet model

Thwaites Glacier is a major contributor to Antarctic mass loss and a key source of uncertainty in future sea-level rise. Ocean-driven melting at its grounding line drives rapid retreat, yet most models treat the transition between grounded and floating ice as a sharp boundary, neglecting kilometer-scale seawater intrusions that develop as the grounding line migrates and forms a grounding zone. Here, we show that actively-melting grounding zones …

Thwaites Glacier could contribute twice as much sea-level rise as previously projected

A new ice sheet model developed by glaciologists at the University of California, Irvine and NASA's Jet Propulsion Laboratory projects that the melting of Thwaites Glacier in West Antarctica will contribute up to 30 millimeters (1.2 inches) of sea level rise by 2100—twice previous estimates—even without additional climate warming.

Seawater seeping under Thwaites Glacier doubles its 2100 sea-level forecast

Warm seawater is reaching kilometres beneath Antarctica’s Thwaites Glacier, and once a computer model accounts for it, the glacier’s projected contribution to sea-level rise this century roughly doubles. The new model reaches that figure without assuming any further warming of the ocean or the air. Unlike most of its predecessors, it also reproduces what satellites have actually watched the glacier do: retreat, thin and speed up, all at once. Th…