Wind-driven oceanic circulation
From Glossary of Meteorology
wind-driven oceanic circulation
That part of the large-scale circulation of the ocean driven by and associated with the stress (force per unit area) applied by the wind at the ocean surface.
The main principles of wind-driven ocean circulation are as follows.
- Wind stress causes transport of water in a thin Ekman surface layer
- If there is a curl to the wind stress, the Ekman layer transport will converge or diverge, causing downwelling or upwelling
- The downwelling or upwelling motions cause fluid columns to squash or stretch vertically, and this causes slow southward or northward flow due to conservation of potential vorticity.
- The southward or northward flow is determined by the Sverdrup relationship, which links the N-S transport of water with the curl of the wind stress. In order to conserve mass, the water returns to its original position via a relatively thin boundary layer adjacent to the western edge of the basin.
