A simple model for wind-driven ocean circulation in unbounded domains

Xinyi Meng, Esteban Gregorio Tabak

An idealized barotropic model satisfying a Stommel–type vorticity balance is formulated for wind–driven circulation in a zonally unbounded channel with spatially varying bottom drag, motivated by the Antarctic Circumpolar Current through Drake Passage. An explicit solution is obtained in the high–drag passage and a Sverdrup interior with western boundary layer is derived in the weak–drag basin; the solutions are matched by continuity of streamfunction and flux. The model provides a simple qualitative explanation for the emergence of a northward Malvinas Current branch when the Antarctic Circumpolar Current crosses the Drake Passage.