An analytical study on the barotropic energy conversion in the lower tropospheric monsoonal flow

Abstract

The mean zonal flow profile along y, for July month at different levels in the lower troposphere and at different longitudes in the Indian region, confined between two latitudinal walls is considered. The analytical function for each zonal flow profile is obtained by expressing it as a cosine Fourier series. A barotropically neutral perturbation of different functional dependency along y, and the wave structure along x is specified initially. Using non-divergent barotropic model in a Beta-plane, the barotropic energy conversion, tendency are evaluated analytically for different observed zonal flow profiles.

The study of the barotropic energy conversion tendency indicates the disturbance at levels 850 and 700 rob receives energy from zonal kinetic 'energy, the most preferred scale is around 6000 km. The barotropically growing wave moves from east to west with phase speed of about 8 m sec-l and minimum local doubling time is about 4 days.