Southern Annular Mode dynamics, projections and impacts in a changing climate

A Purich; JM Arblaster; G Boschat; ZE Gillett; W Hobbs; M Jucker; EP Lim; D Udy; N Abram; E Campitelli; E Doddridge; MH England; A King; L Menviel; A Meyer; V Ortiz Guzmán; R Roy; I Rudeva; P Spence; PG Strutton; T Ziehn

Journal article

Southern Annular Mode dynamics, projections and impacts in a changing climate

A Purich, JM Arblaster, G Boschat, ZE Gillett, W Hobbs, M Jucker, EP Lim, D Udy, N Abram, E Campitelli, E Doddridge, MH England, A King, L Menviel, A Meyer, V Ortiz Guzmán, R Roy, I Rudeva, P Spence, PG Strutton Show all

Nature Reviews Earth and Environment | Published : 2026

DOI: 10.1038/s43017-025-00746-y

Abstract

The Southern Annular Mode (SAM) influences Southern Hemisphere temperature and precipitation, ocean circulation, carbon cycling and the Antarctic cryosphere. In this Review, we examine the dynamics, projections and effects of the SAM, focusing on future implications for the Southern Ocean and Antarctica. The SAM is the leading mode of atmospheric variability in the Southern Hemisphere extratropics, associated with variations in the mid-latitude westerly jet strength and position. The SAM is primarily an internally driven atmospheric process, for which anomalies dissipate in 1–2 weeks; however, sustained SAM anomalies can also be forced by stratospheric processes and tropical Pacific variabil..

View full abstract