A modification to the Munk wind-driven ocean circulation theory

In order to fulfill the no-slip condition at the western and eastern boundaries of the ocean basin, introduced "effective wind stress", which has much larger spatial variations towards the boundaries than in the ocean interior.The effective wind stress can thus be decomposed into spatially slow-varying and fast varying components.Careful scale analysis on the classical Munk wind-driven ocean circulation theory, which consists of the interior Sverdrup flow and the western boundary current but of no eastern boundary current, shows that the wind stress curl appearing in the Sverdrup equation must have negligible spatial variations.In the present model the spatially slow-varying component of the wind stress appears in the Sverdrup equation, and the spatially fast-varying component becomes the forcing term of the boundary equations.As a result, in addition to the classical Munk solution the present model has an extra term at the western boundary which (Northern Hemisphere) increases the northward transport as well as the southward return transport, and has a term at the eastern boundary corresponding to the eastern boundary current.