Repeated loss of the West Antarctic Ice Sheet's Amundsen Sea sector during late Pleistocene interglacials.

Glacigenic detritus from the Amundsen Sea sector’s main outlet glaciers ceased almost entirely during all previous warm periods over the last 800,000 years, documenting drainage-basin loss.

• Why it matters: Direct ice-sheet–proximal evidence for late Pleistocene retreat has been inconclusive, limiting how confidently ocean warming can be linked to West Antarctic deglaciation and sea-level rise.
• What they did: The study analyzed clay mineral assemblages and a microfossil proxy for past ocean temperatures in West Antarctic continental margin sediments spanning the last 800,000 years.
• The result: Seawater warming coincided with the detritus shutdown and is attributed to intensified deep-water advection toward Antarctica’s Pacific margin, supporting that ocean forcing can drive major deglaciation and several-metre sea-level rise.

AI summary of the abstract · may contain errors · not medical advice · read the paper.