Astrophysical fluid dynamics is my primary research interest, and my work currently centers on theoretical treatments for compressible convection in stars. The nonlinear theory using computational fluid dynamics is complemented by detailed observations of velocity fields on the Sun, from both ground-based and satellite instruments. My interests extend to helioseismology, in which the five-minute oscillations of the Sun are used as probes of velocity and temperature structures within the interior. My group seeks to understand the coupling of global-scale convection with rotation by using a series of experiments flown on the space shuttle. My nonlinear dynamical studies in geophysics include thermohaline convection in the oceans and stratified shear flows.