Convective Parameterization in a Quasi-Geostrophic Diagnostic Model of Fronts

Abstract

The quasi-geostrophic ?-equation including a convective parameterization is solved for an idealized frontal structure. A sloping cold front is specified by a simple analytical form for the Q-vector representing constant geostrophic deformation and sheared along-front flow. Diabatic heating due to cumulus convection is parameterized as proportional to the low-level convergence in a way mathematically similar to that used in CISK models. The role of convective heating is to increase the frontogenetic tendency, particularly ahead of the frontal surface at mid-levels.