HR: 14:40h
AN: P23C-05    [Abstracts]
TI: CO2 Clouds, CAPE and convection on Mars: Observations and General Circulation Modeling
AU: * Colaprete, A
EM: anthony.colaprete-1@nasa.gov
AF: NASA Ames Research Center, Moffett Field MS 245-3, Moutain View, CA 94035 United States
AU: Haberle, R M
EM: robert.m.haberle@nasa.gov
AF: NASA Ames Research Center, Moffett Field MS 245-3, Moutain View, CA 94035 United States
AU: Barnes, J R
EM: barnes@coas.oregonstate.edu
AF: College of Oceanic and Atmospheric Sciences, Oregon State University, Corvallis, OR 97331 United States
AB: The largest Martian climate signature is the exchange of carbon dioxide between the atmosphere and the surface, and yet the treatment of this process by climate models remains extremely approximate. It is generally believed that within the polar night a balance exists between diabatic processes, such as radiative cooling, and latent heating from condensing CO2. This assumption manifests itself in Mars General Circulation Models (MGCMs) in such a way as to never allow the atmospheric temperature to dip below the saturation temperature of CO2. However, observations from Mars Global Surveyor (MGS) Radio Science (RS) and the Thermal Emission Spectrometer (TES) have demonstrated this assumption to be, at best, approximate. RS and TES observations within the polar nights of both poles indicate substantial supersaturated regions with respect to CO2 ice. The observed temperature profiles suggest unstable regions containing significant amounts of potential convective energy. The likelihood of convective motions resulting from condensing atmospheric CO2 represents a dramatic shift in the way the Martian polar night is viewed and has important implications for understanding the Martian CO2 cycle and climate.
DE: 3346 Planetary meteorology (5445, 5739)
DE: 3349 Polar meteorology
DE: 5445 Meteorology (3346)
DE: 5739 Meteorology (3346)
SC: Planetary Sciences [P]
MN: Fall Meeting 2005