Diabatic Heating and Cooling in the Equivalent-barotropic Atmosphere

Abstract

A BAROCLINIC atmosphere in which the wind direction does not change along the vertical, defined by the relations: is the average wind in a layer with vanishing boundary values of the vertical velocity ωp = dp/dt, has been named¹ ‘equivalent-barotropic’ because the divergence vanishes at a level n defined by: Consequently the vorticity equation, which in a consistent geostropic form can be written: takes at the level n the barotropic form: It is clear that together with the geostrophic assumption equation (1) implies that: These relations have been used² to determine an average vertical velocity field for the equivalent-barotropic atmosphere. We wish to point out here that they also imply the existence of a realistic field of diabatic heating and cooling in the equivalent-barotropic atmosphere.