FLOW OVER A LOCALIZED HEAT SOURCE

Abstract

A general theoretical model has been designed to analyze the properties of perturbations induced when air flows over an isolated warm portion of the earth's surface. The dependence of these perturbations on wind and temperature conditions of the large-scale flow as well as on the orientation of the local heat source with respect to the prevailing flow has been examined by performing two numerical integrations. The heat source is considered to be narrow (10 km) in the x-direction and infinite in the y-direction. The computations show that when the prevailing flow is strong, and normal to the heat source, the induced perturbations are weak. The surface wind over the heat source is accelerated and the wind at the leeward edge is stronger than at the windward side. Consequently, there is downward motion over the entire extent of the heat source. The corresponding results for the case when the prevailing flow is parallel to the heat source show considerably stronger induced perturbations and the heat source is characterized by upward motions.