Aspects of Tropical Meteorology: West Africa and North America

Iowa State University, Ames IA

Investigators

Abstract

The project will investigate the formation and maintenance of a key component of the tropical circulation that affects summer rainfall over continental United States: tropical storms, or hurricanes, in the Atlantic. The genesis of Atlantic hurricanes, which often make landfall over continental US, is in the African easterly waves, and the project will advance understanding of the dynamical factors controlling African easterly wave activity. The waves themselves are posited to arise from hydrodynamic instability of the African easterly jet, and Dr. Chen's research will examine the formation, maintenance, and variability of this lower tropospheric jet using the modern reanalysis data sets, which provide a wealth of information on circulation and diabatic heating. The diagnostic research will provide a new assessment of the dynamic and thermodynamic interactions involved in the formation and development of African easterly waves, building on the pioneering analyses of Carlson, Burpee, and Reed that date back a quarter century.