Tropical wave dynamics

Description

This research may be divided into the following three parts: (a) waves forced by condensation heating in the troposphere, (b) the local barotropic instability produced by a spatially varying basic flow, (c) the numerical modeling of the wave-basic flow interactine system. In the first part, the problem of the vertical structure of tropical waves generated by cumulus heating is treated for the following two cases: (1) heating is controlled by large-scale low-level convergence and (2) heating receives no feedback from large-scale motion. In the first case it is shown that waves which have a short vertical wavelength relative to the vertical scale of heating are stable, and the structure of the most unstable solution is computed. In the second case it is shown that the forcing is most efficient for the longest zonal wavelength and that the most favored vertical wavelength is about twice the vertical scale of the heating. The effect of cumulus damping on planetary-scale Kelvin-like oscillation gives solution which resembles certain observed tropical circulation.

Subjects