Work

Inter-basin contrast in the Southern Ocean warming

Year: 2025

Type: article

Abstract: The Southern Ocean (SO) is a major contributor to global ocean heat uptake, exhibiting deep-reaching warming trends within the 35°S-55°S band. Here, we reveal a notable inter-basin contrast in the SO warming rates. Over the past six decades, the warming of the 0-700 m Atlantic-Indian sector was 40.0 ± 5.7% faster than the Pacific sector, nearly doubling at ~44°S. Ocean-only and coupled model experiments suggest that this basin-scale contrast arises from alterations in wind-driven heat redistribution rather than surface heating. Specifically, the intensification and poleward migration of westerly winds are more prominent in the Atlantic-Indian sector, leading to stronger upper-layer heat convergence. The inter-basin warming contrast is projected to persist and amplify throughout the remainder of the 21st century. This study highlights the inter-basin contrast in the past and future SO warming, with useful implications for understanding regional changes in the SO climate, ice mass, and marine ecosystems. This work highlights a sharp warming contrast within the Southern Ocean: the Atlantic-Indian sector warms faster than the Pacific due to wind-driven heat transport. The contrast is projected to persist, shaping future climate and ocean change.

Source: Nature Communications

DOI: 10.1038/s41467-025-64112-8