Synergistic atmosphere-ocean-ice influences have driven the 2023 all-time Antarctic sea-ice record low

Antarctic sea ice extent (SIE) reached a new record low in February 2023. We examine the evolution of the coupled ocean–atmosphere–sea ice system during the 12 months preceding the record using observations, reanalyses, and a regional ocean–sea ice coupled model (NEMO3.6–LIM3). The 2022–2023 annual cycle featured consistently low SIE throughout the year, anomalously rapid sea ice retreat in December 2022, and nearly circumpolar negative SIE anomalies in February 2023. Advection-induced positive air temperature anomalies inhibited sea-ice growth in most regions, while strong southerly winds in the Amundsen–Ross Sea associated with an anomalously deep Amundsen Sea Low (ASL) drove substantial sea-ice transport. The multiphysical processes operating in preceding seasons preconditioned the system and contributed to the spring-to-summer record low.

Jinféi Wang, François Massonnet, Hugues Goosse, Hao Luo, Antoine Barthélémy, Qinghua Yang