Tropical Atmospheric Dynamics

点击翻译按钮获取中文摘要

Research under this award involves four important aspects of atmospheric motion. Although some of the research involves general processes, the focus is primarily on the tropics. (1) Using semi-geostrophic theory, the PI will calculate the large-scale atmospheric response to the passage of squall lines. The task require the identification and use of specialized numerical methods. Model results will be verified with data from a recent observational field program, Pre-STORM. (2) The Intertropical Convergence Zone (ITCZ), a band of tropical convection and major source of heat release into the atmosphere, annually migrates from the Northern Hemisphere to the Southern Hemisphere and back roughly following the solar insolation maximum and is associated with a large-scale circulation pattern known as the Hadley cell. There is a distinct asymmetry in the strength of the Hadley cell in the two hemispheres. The PI will investigate how the position and intensity of the ITCZ, interacting with the large-scale atmospheric flow, affect the Hadley circulations. (3) Many studies of tropical cyclones are limited by the assumption of axisymmetry. The PI is developing a new model for the study of tropical cyclones which will allow for asymmetric motion and will use it to study aspects of the observed banded structure of hurricanes. In addition, he is developing a general tropical cyclone model that can be run on a personal computer. This should prove to be an excellent educational as well as research tool. (4) Theoretical work aimed at developing models which are valid for highly curved flow will also be continued. The PI is an excellent theoretician and mathematician who continues to make important contributions to the field of tropical dynamics. Much of the research will be done in collaboration with a colleague in the Mathematics Department.