On the Accuracy of the WKBJ Approximation to the Nonseparable Quasi-geostrophic Baroclinic Instability Problem

Abstract

The accuracy Of the WKBJ approximation to the nonseparable quasi-geostrophic baroclinic instability problem is investigated. By direct comparison with an effectively exact solution, we demonstrate for a particular class of frontal zones that the range of parameters for which agreement is attained is rather limited. Most importantly, the WKBJ solution is shown to be significantly in error for frontal zones representative of typical atmospheric conditions.