A three-dimensional theory of coastal currents and upwelling over a continental shelf

The steady circulation of a homogeneous ocean is investigated in the region where the bottom rises to meet the surface at the coast as over a continental shelf. In this region the bottom Ekman layer becomes important and carries the coastal upwelling from the shelf interior region to the surface Ekman layer. A strong longshore current is produced in the shelf boundary layer and for certain distributions of wind stress an offshore deep counter-current is formed. At a given latitude the longshore flow near the coast depends on the local wind, whereas the offshore counter-current and the net northwards transport in the shelf layer are a function of the latitudinal distribution of wind stress.