HR: 0800h
AN: P31A-0200    [Abstracts]
TI: Observed Dust Devil Tracks in the North Polar Region of Mars
AU: * Drake, N B
EM: ndrake@austincollege.edu
AF: Austin College, 900 North Grand Avenue, Sherman, TX 75090 United States
AU: Tamppari, L K
EM: leslie.tamppari@jpl.nasa.gov
AF: Jet Propulsion Laboratory/California Institute of Technology, 4800 Oak Grove Drive M/S 264-623, Pasadena, CA 91109 United States
AU: Baker, D
EM: dbaker@austincollege.edu
AF: Austin College, 900 North Grand Avenue, Sherman, TX 75090 United States
AB: Dust devils are low pressure, warm-core convective vortices that form at the bottom of convective plumes, lifting dust into the atmosphere. This process removes a thin layer of high-albedo dust from the Martian surface, exposing the lower-albedo surface below. This characteristic `track' can be observed in Mars Global Surveyor's (MGS) Mars Orbital Camera Narrow-Angle (MOC-NA) images. Both active dust devils and dust devil tracks have been observed on Mars. Because the Phoenix Mars mission will land between 65-72N carrying a stereo imager, pressure sensor, and upward-looking lidar, understanding dust devils and wind phenomena in this region is of interest to the Phoenix team. Until now, dust devils occurring in the northern polar latitudes (65-72N) have not been studied or documented. We have examined all 1,734 available MOC-NA images in the 65-72N latitude region and have created a database categorizing these MOC-NA images. Of the 1,734 images examined, 162 images (9.3%) contain dust devil tracks or wind streaks. We have observed that dust devils appear to occur near contrasting albedo patterns. Whether dust devils are more prevalent in such regions due to the thermodynamic properties of these regions, unique soil composition, or mere coincidence is unclear. Ongoing work consists of measuring the direction of observed dust devil tracks and wind streaks in this region. These data will indicate prevalent wind direction in each image, allowing the Phoenix team to use this information in selecting a landing site. We will present our results to date.
DE: 3329 Mesoscale meteorology
DE: 3349 Polar meteorology
DE: 5445 Meteorology (3346)
DE: 5462 Polar regions
SC: Planetary Sciences [P]
MN: Fall Meeting 2005