The Southern Annular Mode: Variability, trends, and climate impacts across the Southern Hemisphere
Ohio University · British Antarctic Survey
Abstract
Abstract The Southern Annular Mode (SAM) is the leading mode of extratropical Southern Hemisphere climate variability, associated with changes in the strength and position of the polar jet around Antarctica. This variability in the polar jet drives large fluctuations in the Southern Hemisphere climate, from the lower stratosphere into the troposphere, and stretching from the midlatitudes across the Southern Ocean to Antarctica. Notably, the SAM index has displayed marked positive trends in the austral summer season (stronger and poleward shifted westerlies), associated with stratospheric ozone loss. Historical reconstructions demonstrate that these recent positive SAM index values are unprecedented in the last…
Citation impact
- FWCI
- 30.51
- Percentile
- 100%
- References
- 196
Authors
2Topics & keywords
- Southern Hemisphere
- Westerlies
- Antarctic oscillation
- Climatology
- Stratosphere
- Extratropical cyclone
- Middle latitudes
- Polar vortex
- Climate action