Milankovitch Forcing Of Equilibrium Ground-Ice On Mars.
O. Aharonson1 , E. Vos, Dept. Of Earth & Planetary Sciences, Weizmann Institute Of Science, Rehovot, Israel
(Oded.Aharonson@Weizmann.Ac.Il), 1 Also At: Planetary Science Institute, Tucson, Arizona, Usa., N. Schorghofer,
Planetary Science Institute, Tucson, Arizona, Usa., F. Forget, Laboratoire De Meteorologie Dynamique/Ipsl, Sorbonne Universite, Ens, Psl Research University, Ecole Polytechnique, Cnrs, Paris, France.

Summary
Exchangeable Ice Deposits Are Present Today On Mars
In Polar Caps And As Shallow Subsurface Mid-Latitude
Ground-Ice. Geologic Evidence Indicates These Reservoirs Waxed And Waned In The Past In Concert With The
Emplacement And Loss Of Equatorial Glaciers. Here We
Use A Climate Model [1], To Determine The Distribution Of
The Mid-Latitude Ground Ice Deposits Assumed To Be In Diffusive Vapor Equilibrium With The Atmosphere, At Present
And Under Past Orbital Configurations. The Ground-Ice
And Its Distribution Have Profound Consequences For Various Aspects Of Mars Climate, Not Only Playing A Central
Role In The Water Cycle, But Also Determining The Seasonal
Duration Of Co2 Stability At The Surface. The Model Predictions For The Extent Of The Equilibrium Ice-Table In
The Past Are Successful In Matching The Latitudinal Distribution Of Terrain Softening Geologic Features Previously
Mapped [2, 3, 4] And Exposures Of Sub-Surface Ice In
Recently Formed Craters [5].