HR: 0800h
AN: P31A-0197    [Abstracts]
TI: Thermal Characterization of proposed Phoenix Landing Sites
AU: * Titus, T N
EM: ttitus@usgs.gov
AF: U.S. Geological Survey, 2255 N. Gemini Dr., Flagstaff, AZ 86001 United States
AU: Prettyman, T H
EM: thp@lanl.gov
AF: Los Alamos National Laboratory, 1981 Camino Uva, Los Alamos, NM 87544 United States
AU: Colaprete, A
EM: tonyc@freeze.arc.nasa.gov
AF: NASA Ames Research Center, Space Science Div MC 245-3 Moffet Field, Mountain View, CA 94035 United States
AB: With recent detection from the GRS suite of instruments of a wide spread water ice table in the Mars polar regions and the impending landing of the Phoenix Lander, it is important to understand the thermo-physical properties and hydration states of both the ice table and the top layer of soil that covers the ice table. Due to the presence of a high thermal inertia ice table near the surface, the top meter of the regolith is an important heat source during the fall and early winter, causing the sublimation of CO_2 ice, and significantly reducing the net accumulation of CO_2 ice. The ice table acts as a thermal capacitor, storing heat during the summer, and releasing the heat during the polar night. In order to estimate the effect of this process on the net accumulation of seasonal CO_2, we use Mars Global Surveyor (MGS) Thermal Emission Spectrometer (TES) temperature observations immediately following the springtime disappearance of seasonal CO_2 to estimate the thermal inertia of a 2 layer model at the 3 proposed Phoenix landing sites. We then use this model to estimate the thermal contribution of the regolith to the CO_2 cycle energy balance. Comparisons to both CO_2 mass estimates from the Mars Odyssey (ODY) Neutron Spectrometer (NS) and mass estimates from Mars General Circulation Models (GCM) will be made. Estimates of the energy flux balance from TES temperature and albedo measures combined with mass estimates from the NS and heat storage estimates from this study, will be used to estimate atmospheric heat transport. These estimates of atmospheric heat transport will also be compared to the GCMs.
UR: http://www.mars-ice.org
DE: 0475 Permafrost, cryosphere, and high-latitude processes (0702, 0716)
DE: 0762 Mass balance (1218, 1223)
DE: 5422 Ices
DE: 5462 Polar regions
DE: 6225 Mars
SC: Planetary Sciences [P]
MN: Fall Meeting 2005