Ageostrophic Subsynoptic-Scale Baroclinic Instability

Abstract

The discrete-level baroclinic eigenproblem developed by Satyamurty et al., based on a Boussinesq primitive equation model, is solved by a shooting method for very high vertical resolution. It is found that the vertical resolution used by Satyamurty et al. (0.5 km) is insufficient to eliminate spurious critical layer instability. Peaks in the instability spectrum at very short wavelengths (< ? 1000 km) found by them are spurious and are not the result of ageostrophic terms.