Dynamics of the Southern Ocean Circulation

The Southern Ocean circulation connects the ocean basins as well as the upper and deep layers of the ocean. As a result, the region has a profound influence on the global ocean circulation and climate. The Antarctic Circumpolar Current and the overturning circulation are dynamically linked through interactions between the mean flow, eddies, topography, air–sea forcing, and mixing and stirring by small- and mesoscale processes. A new dynamical paradigm is emerging that emphasizes the fully three-dimensional nature of the circulation, including the localization of meridional and vertical exchange of momentum, vorticity, and tracers by interactions between the flow and topography. Changes observed in the Southern Ocean in recent decades have implications for global climate and provide insight into the response of the Southern Ocean circulation to changes in forcing.