Antarctic Ice Sheet Gains Mass in East Antarctica Amid Unusual Tropical Warmth

International scientists using GRACE and GRACE-FO satellite gravity data reported that the Antarctic ice sheet, which had been shedding an average of 1405 billion tonnes per year from 2003 to 2024, reversed its trend from July 2021 to April 2023, gaining about 6950 billion tonnes. The increase was concentrated in East Antarctica, especially in Queen Mary Land and Wilkes Land, which together contributed roughly 68 % of the added mass.

The team links this temporary boost to an unprecedented warming of tropical sea surface temperatures that generated a Rossby wave, reshaping atmospheric flow and creating conditions for stronger low-pressure systems south of Australia and high-pressure zones along the East Antarctic coast. These changes directed more atmospheric river moisture from the Indian Ocean onto the continent, producing heavy snowfall. While East Antarctica saw this gain, some West Antarctic sectors still experienced ice loss due to basal melting and glacier discharge. The authors caution that the episode does not signal a reversal of long-term warming trends, noting that human-induced climate change likely contributed only about 9 % of the observed snowfall excess.