Atmospheric River Creates Record-high Temperatures and Surface Melt in Antarctic Peninsula

NPJ Climate and Atmospheric Science, 4 December 2023

A similar atmospheric river swept intense heat and rainfall across the Antarctic Peninsula in February 2022, setting record-high surface melt compared to the previous four decades. The warm band of subtropical moisture directly hit the northwestern and northern side of the Peninsula. The eastern Peninsula then dramatically warmed as these winds flowed over the mountain range, releasing a large amount of rainfall on the way up before cresting over the peaks and creating a rush of warm air on the way down. The widespread melt impacted the Wilkins, George VI and Larsen C ice shelves. Unusually warm sea surface temperatures in the subtropical southern Pacific combined with large-scale atmospheric circulation patterns to propel the atmospheric river toward the Peninsula, triggering record-high temperatures and surface melt. Extreme events such as these more likely to occur as the climate warms, and generate widespread meltwater ponds that weaken ice shelf stability, as shown in earlier Antarctic ice shelf disintegration events on the Peninsula.

https://www.nature.com/articles/s41612-023-00529-6