HR: 0830h
AN: C21C-0828    [PDF]
TI: Understanding the Vertical Distribution and Exchange of $H_2O$ in the Subsurface of Mars.
AU: * Schorghofer, N
EM: norbert@gps.caltech.edu
AF: California Institute of Technology, MC 150-21, Pasadena, CA 91125 United States
AU: Aharonson, O
EM: oa@caltech.edu
AF: California Institute of Technology, MC 150-21, Pasadena, CA 91125 United States
AB: Prompted by the recent discoveries of Mars Odyssey, we aim to better understand the exchange of water vapor between the atmosphere and the subsurface and the vertical distribution of water ice and adsorbate. We model vapor transport, adsorption, and sublimation of water ice in the regolith over diurnal, seasonal, and millennial time scales. We find that in long-term equilibrium the transition to the subsurface ice table is sudden, and, as expected, the depth to the ice table can be determined from the frost point at the surface. Accumulating subsurface ice reduces the vapor transport deep into the regolith, but, eventually, ice can amass through sublimation to great depths. Physical adsorption of water onto the regolith may deplete the water vapor substantially and can lead to considerable diurnal breathing, but it has little influence on the frost point. These are examples of dynamical effects not described by standard equilibrium models.
DE: 1823 Frozen ground
DE: 5416 Glaciation
DE: 5470 Surface materials and properties
DE: 6225 Mars
SC: Cryosphere [C]
MN: 2003 Fall Meeting