The Effects of Release of Latent Heat on the Vorticity of a Tropical Storm over Land

Abstract

The effect of the release of latent heat on the thermal vorticity of Hurricane Diane (1955) is examined when it passed over the east coast of the United States as a weakened tropical storm. A form of the thermodynamic energy equation is used as the diagnostic equation for this study. Because of uncertainty in the data, as well as incomplete physical understanding of the interaction, between synoptic and convective scales, several alternative models are used which employ different assumptions on the influence of convection and the vertical distribution of humidity and temperature. In agreement with the results of previous investigations, Diane was found to weaken after landfall as a result of the lifting of negatively buoyant air at the storm center. However, as the storm readjusted to its new environment the stability at the center again decreased. The latent heating, as represented by its horizontal Laplacian, then becomes effective in the maintenance and redevelopment of the storm.