Toward a satellite-based observation of atmospheric heat source over land

Atmospheric heat source is concerned in global circulation and monsoon studies. Its accurate quantification by conventional methods needs high-quality gridded meteorological data or energy flux data, which are usually not available in most regions. In this study, we present a simple method to quantify apparent heat source over land. The required inputs are net radiation at the top of atmosphere, terrestrial water storage change, river runoff, and ground heat flux. The former two can be directly observed by satellites, the runoff is measured for major rivers in the world and is to be measured by an upcoming satellite mission, and the ground heat flux is a small term, which can be estimated by satellite remote sensing or land surface modeling. Two applications of this method demonstrate its potential in quantifying the variations of heat source over land at global and regional scales.