The hydraulics of local separation applied to middle layer upwelling at the exit of Shelikof Strait, northwest Gulf of Alaska
摘要
Oceanic upwelling/downwelling is generally understood from the viewpoint of ageostrophic current divergence. However, this theory does not explain the middle layer (120–200 m) upwelling around the southern coast of the Shelikof Strait exit, northwest Gulf of Alaska. Hence, the present study investigates the mechanism of this internal upwelling. An analysis of the simulation results for the climatological January mean indicates that this middle layer upwelling coexists with a barotropic geostrophic current, which crosses the iso-depth of an inclined isopycnal surface. This upsloping flow (upsloping relative to a geopotential surface) is represented by the Montgomery stream function on the isopycnal layer at