Drs. Glenn Flierl and Adam Showman will carry out a program of modeling the circulations on gas giant planets (both solar and extra-solar) to understand the role of rotation, internal heat sources, and heating from the star on the dynamics. They have extended the general circulation model developed at MIT to include deep spherical geometry, fully non-hydrostatic dynamics, strong density variations using the anelastic approximation, and an equation of state suitable for hydrogen and helium at high pressures. The objective is to understand thermal convection and the production of columnar zonal flow, the circulations driven by the equatorial heating and polar cooling, the role of eddies, and the interactions between the various kinds of motions. They will study both two- and three-dimensional models and relate them to previous, more idealized models and analytical theories.
The flows on gas giants remain a fascinating problem in geophysical fluid dynamics. By examining in detail convective and instability processes and the interactions between the deep and surface circulations, this research team will learn more about the ways in which these processes set the mean thermal structure and the forces which produce the prominent zonal flows.
Convection and interactions between eddies and mean flows are general features in atmospheres and oceans. Giant planets offer a laboratory for studying and modeling these processes. This kind of knowledge will be important in interpreting the new data being gathered about the extra-solar gas giants as well. Numerical models offer an approach to understanding geophysical flows, but the most difficult aspect in using them is analyzing the results and understanding the processes, including study of simplified representations. Training students and postdocs in this area is important to advance our capabilities in planetary fluid dynamics (including climate dynamics). ***
