Aspects of the baroclinic boundary layer

The Ekman-Taylor boundary layer model is solved for the case of a linear variation of the geostrophic wind with height. The two-layer model couples a Monin-Ibukhov similarity layer to an Ekman layer with a vertically constant eddy diffusivity. The presence of the thermal wind contributes both an along-isotherm and a cross-isotherm component to the boundary layer flow. The along-isotherm flow is supergeostrophic and results from the net downward transport of geostrophic momentum by the eddies. The cross-isotherm flow is toward the warm air and results from the Coriolis deflection of the geostrophic momentum-rich air aloft that has been mixed downward. The effect of the baroclinity (i.e., the thermal wind shear) on the wind field is conveniently summarized geometrically. -from Authors