Satellite-derived diabatic heating structure and its influence on meridional circulation and energetics of Asian summer monsoon

This study describes how satellite derived estimates of diabatic heating profiles and their space-time variations influence the meridional circulation pattern and zonal kinetic energy of the Asian summer monsoon.;It is found that the meridional stream function is not particularly sensitive to the basic state wind field, and although the magnitude of the energy conversion efficiency parameter changes according to how the mean wind structure is specified, the changes are minor relative to concomitant changes from varying the heating structure. Comparison of energy conversion efficiency parameters from the model to analogous quantities calculated from the ECMWF dataset throughout the course of the monsoon season does not indicate agreement in either the nature or magnitude of the variations. However, a change in the magnitude of the vertical heating structure in the northern edge of the domain produces variations in the domain efficiency parameter somewhat comparable to that from the ECMWF dataset.;EOF decomposition shows that the diabatic heating structures are largely determined from major cloud bands detected in the INSAT and SSM/I images. Since the dynamical model is 2-dimensional, the scale of spatial averaging for the heating structure is important in determining the magnitudes of meridional mass fluxes and the efficiency in kinetic energy conversion.;Comparison of the retrieved heating and thermal stability structures from ECMWF analyses shows consistent seasonal variation in positioning and magnitude. Comparison of vertical wind fields from the model, forced with cloud-free only radiative cooling, shows better agreement with the pattern of the vertical wind fields from the ECMWF analyses, when the cloud induced heating component is of relatively small magnitude. The agreement in the pattern of the modeled vertical wind fields produced by the total heating term, and the ECMWF wind fields is better whenever the total heating rates are strong and deep.;In conclusion, this study demonstrates that the diabatic heating structures derived from SSM/I measurements are representative of monsoon processes and capture features not revealed in the ECMWF optimal analyses. This suggests that the retrieved heating could be used for physical initialization purposes to improve global predictions.