Widespread West Antarctic Retreat Began Already in 1940s

Proceedings of the National Academy of Sciences, 26 February 2024

An extreme El Niño warming in the 1940s triggered dramatic thinning and retreat of the massive Thwaites and Pine Island glaciers in West Antarctica, sending them into a sustained period of ice loss from which they did not recover, even when cooler temperatures later ensued. This is the first study to link the retreat of these two glaciers to one relatively short warming period that pushed them both out of balance; apparently irreversibly, without the ability to recover. Notably, authors found that the entire Amundsen Sea region of the West Antarctic Ice Sheet was and remains extremely sensitive to ocean and atmospheric warming. Thwaites in particular plays a vital role in regulating West Antarctic ice stability, restraining global sea-level rise, because it functions as a gateway holding back the huge weight of the ice sheet behind it, which holds 4-7 meters total sea-level rise.

Full paper: https://www.pnas.org/doi/full/10.1073/pnas.2211711120
Plain-language News Brief: https://stories.uh.edu/2024-on-thin-ice/index.html