On moist quasi-geostrophic barotropic instability.

Abstract

The instability of quasi-geostrophic internal modes in a moist model atmosphere with the presence of a purely barotropic basic flow is investigated. The author's formulation for a self-induced condensational heating is adopted in a prototype model that has a hyperbolic-tangent barotropic basic flow. It is shown that a cooperative interaction can occur between the quasi-geostrophic internal modes and the implicitly embedded convection. An application of this model is made with a basic flow of an easterly jet that has a Gaussian distribution. -from Author