The Goldsbrough–Stommel Circulation of the World Oceans

Abstract

Goldsbrough first showed how the mass flux at the ocean surface due to the difference between evaporation and precipitation could induce barotropic flow in the ocean interior through the requirement of vorticity conservation. Stommel proposed to close this circulation by adding the western boundary currents. Here, a first-otder description of the Goldsbrough-Stommel circulation for the world oceans is presented, using available climatologies. While such flows are an order of magnitude smaller than the wind-driven circulation, the interaction between the Goldsbrough-Stommel gyres and the wind-driven and thermally driven circulation determines the salinity distribution of the world oceans. Therefore, it is important to study the Goldsbrough-Stommel circulation and its interaction with motions driven by other forcings. In addition, the western boundary currents required to close the Goldsbrough interior and to satisfy interbasin mass transport can be substantial. In the Atlantic the southward western boundary current reaches two Sverdrups (Sv ≡ 106 m3 s?1) at 35°N. It is suggested that this adverse current causes a southward shift in the separation point of the Gulf Stream; a simple model indicates that the displacement is about 75 km.