HR: 09:30h
AN: P21E-07    [Abstracts]
TI: Synthesis of MGS Observations of the 2001 Global Dust Storm on Mars: Implications for Atmospheric Dynamics
AU: * Haberle, R M
EM: Robert.M.Haberle@nasa.gov
AF: NASA/Ames Research Center, Space Science and Astrobiology Division, Moffett Field, CA 94035 United States
AU: Noble, J
EM: noble@met.sjsu.edu
AF: San Jose State University, Dept. Meteorology, San Jose, CA 95912 United States
AU: Murphy, J R
EM: murphy@nmsu.edu
AF: New Mexico State Univ, Dept. Astronomy, Las Cruces, NM 88003 United States
AU: Bridger, A F
EM: bridger@met.sjsu.edu
AF: San Jose State University, Dept. Meteorology, San Jose, CA 95912 United States
AU: Hollingsworth, J L
EM: jeffh@humbabe.arc.nasa.gov
AF: San Jose State University, Dept. Meteorology, San Jose, CA 95912 United States
AU: Cantor, B
EM: cantor@msss.com
AF: Malin Space Science Systems, PO 910148, San Diego, CA 92191 United States
AU: Malin, M
EM: malin@msss.com
AF: Malin Space Science Systems, PO 910148, San Diego, CA 92191 United States
AU: Smith, M
EM: Michael.D.Smith@nasa.gov
AF: NASA Goddard Space Flight Center, Code 693, Greenbelt, MD 94035 United States
AB: We have combined the Mars Global Surveyor observations of the 2001 global dust storm on Mars in order to determine what components o the general circulation are involved in the onset and evolution of this storm. These observations include Mars Obiter Camera daily global weather maps, Thermal Emission Spectrometer measurements of atmospheric temperature and 9-micron dust opacity, and Mars Horizon Sensor Assembly measurements of middle atmosphere temperatures. Based on our analysis of these data, we adopt the following working hypothesis. The storm was triggered by traveling baroclinic eddies in combination with a topographically enhanced cap edge circulation in the southwest region of the Hellas basin. Westerly winds carried the dust eastward into a longitude sector where a wave -one stationary wave pattern advected the dust southward over the polar cap. As the dust reached higher altitudes in this longitude sector, the subsequent heating over a deep part of the atmosphere amplified the wave-one stationary wave exciting a possible RossbyWave train that propagated into the opposite hemisphere. Shortly after the wave-one reached its maximum amplitude, dust lifting began in the Syria-Claritas region south of Tharsis, a development possibly related to the propagating Rossby Wave train. Lifting in this region, which was the major source of atmospheric dust, may have been sustained by enhanced thermal tides augmented by upslope/downslope flows. Zonal mean westerlies and the mean meridional circulation affected the largely eastward movement of dust during storm onset, and eventual northward and global dispersion. These ideas will be tested with general circulation model simulations.
DE: 5405 Atmospheres (0343, 1060)
DE: 5445 Meteorology (3346)
SC: Planetary Sciences [P]
MN: Fall Meeting 2005