A Mars Whole Atmosphere Climate Model: Development and Applications

Regents Of The University Of Michigan - Ann Arbor, Ann Arbor MI

Investigators

Abstract

The entire atmosphere of Mars is modeled from the surface to 300 km. The integrated approach establishes the coupled energetics, dynamics, and chemistry of the atmosphere from the ground to the exosphere. Quantification of the physical processes that couple the lower Martian atmosphere to the upper Martian atmosphere permits quantification of the impact of seasonal and solar-cycle variations of atmospheric dust-loading on the identified coupling processes, and consequently an examination of the of dust storm evolution and impact throughout the Martian atmosphere. The "Whole Atmosphere Climate Model" (WACM) general circulation code currently in use for modeling of the Earth atmosphere is adapted to the upper Martian atmosphere, and is joined to a new finite difference dynamical core originally designed for fine-mesh gridding in the earth's lower atmosphere. That lower atmosphere methodology is adapted to permit a terrain-following vertical coordinate system to accommodate the significant variations of Martian topology. Model verification and tuning is provided by Mars Global Surveyor and Mars Odyssey neutral and ion atmospheric density profiles, altitude profiles of neutral temperature, and inferred winds - so that a predictive capability of future Martian conditions is established. The adaptation of circulation models developed for the Earth atmosphere to the Martian atmosphere permits a new examination and evaluation test bed for improved physics-based model development on both planets.