Collaborative Research: Models of the deep circulation of gas giants: solar heating, convection, and zonal flows

AST 0708106FlierlAST 0708698 ShowmanDr.Glenn Flierl和Adam Showman将对气态巨行星(包括太阳和太阳系外行星)的环流进行模拟，以了解自转、内部热源和恒星加热对动力学的作用。他们扩展了麻省理工学院开发的一般环流模型，包括深球形几何结构，完全非流体静力学，使用滞弹性近似的强密度变化，以及适用于高压下氢和氦的状态方程。目的是了解热对流和柱状纬向流的产生，赤道加热和极地冷却驱动的环流，涡旋的作用，以及各种运动之间的相互作用。他们将研究二维和三维模型，并将它们与以前更理想化的模型和分析理论联系起来。气体巨星上的流动仍然是地球物理流体动力学中一个引人入胜的问题。通过详细研究对流和不稳定过程以及深层和地表环流之间的相互作用，这个研究小组将更多地了解这些过程如何设定平均热结构和产生显著纬向流的力。对流以及涡流和平均流之间的相互作用是大气和海洋中的普遍特征。巨行星为研究和模拟这些过程提供了一个实验室。这类知识对于解释正在收集的有关太阳系外气体巨星的新数据也将是重要的。数值模型提供了一种理解地球物理流动的方法，但使用它们最困难的方面是分析结果和理解过程，包括研究简化表示法。对这一领域的学生和博士后进行培训对于提高我们在行星流体动力学(包括气候动力学)方面的能力很重要。

AST 0708106FlierlAST 0708698ShowmanDrs. 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 circulationmodel 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 hydrogenand helium at high pressures. The objective is to understand thermal convection and the productionof 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).***