HR: 0800h
AN: P11A-0961    [Abstracts]
TI: A Large-Scale Atmospheric Equalization Technique for THEMIS Data
AU: * Anderson, F
EM: anderson@higp.hawaii.edu
AF: HIGP: University of Hawaii at Manoa, 1680 East West Road, Honolulu, HI 96822 United States
AU: Hamilton, V
EM: hamilton@higp.hawaii.edu
AF: HIGP: University of Hawaii at Manoa, 1680 East West Road, Honolulu, HI 96822 United States
AB: Spaceborne thermal infrared observations of Martian surface emissivity using the Mars Odyssey THEMIS instrument can offer a revealing look at the mineralogical makeup of the planet at unprecedented spatial resolution. In areas of high topographic relief, however, varying atmospheric path length makes it difficult to qualitatively or quantitatively compare spectra at different elevations. We describe a technique that normalizes the atmospheric signature across the image, minimizing the effects of path length. As expected, the amplitude of the required normalization is shown to vary seasonally, suggesting that atmospheric dust plays an important role in the extinction. A lack of this effect at 12.57$\mu$m appears to exclude water vapor or ice crystals as a major component of the phenomenon.
DE: 5409 Atmospheres--structure and dynamics
DE: 5410 Composition
DE: 5464 Remote sensing
DE: 5494 Instruments and techniques
DE: 6225 Mars
SC: Planetary Sciences [P]
MN: 2004 AGU Fall Meeting