We consider a model, and variations about it, that explains the large-scale features of ocean gyres and that lies at the core of ocean circulation theory — the steady, forced-dissipative, homogeneous model of the ocean circulation first formulated by Stommel

Such models explain many of the zeroth-order features of the ocean, in particular the existence of gyres and the appearance of intense western boundary currents

Thermodynamic effects can effectively be eliminated by the simple device of vertical integration; the resulting equations are linear, and the only external forcing is that due to the wind stress

The resulting model then, at the price of some comprehensiveness, gives a useful picture of the wind-driven circulation of the ocean

Can you see the Gulf Stream?