Antarctic ice sheet mass loss slowdown linked to tropical ocean warming

A study published in the journal Nature reveals that the temporary slowdown in Antarctic ice sheet mass loss between 2021 and 2023 was driven by warming in the tropical warm pool, located at the intersection of the western Pacific and eastern Indian Oceans.

Researchers from the Institute of Oceanology of the Chinese Academy of Sciences and the University of California, Santa Barbara, found that this warming triggered Rossby waves. These large-scale atmospheric waves created a dipole circulation pattern, resulting in high-pressure anomalies over East Antarctica. This process redirected moisture-rich air from the Indian Ocean toward the continent via atmospheric rivers, causing increased snowfall that offset some ice loss.

While the Antarctic ice sheet lost an average of approximately 140.5 billion tons of ice annually between 2003 and 2024, the period from July 2021 to April 2023 saw a mass increase of about 695 billion tons, primarily in East Antarctica. Experts note that this phenomenon may occur only once every decade, suggesting that any observed increase in ice mass is likely temporary and does not counteract the long-term effects of global warming.