Mathematics – Logic
Scientific paper
Sep 2009
adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=2009dps....41.5704n&link_type=abstract
American Astronomical Society, DPS meeting #41, #57.04
Mathematics
Logic
Scientific paper
The Compact Reconnaissance Imaging Spectrometer for Mars (CRISM) aboard the Mars Reconnaissance Orbiter (MRO) collects hyperspectral images from 0.362 to 3.92 μm at 6.55 nanometers/channel, and at a spatial resolution of 20 m/pixel. The 1-2.6 μm spectral range is often used to identify and map the distribution of hydrous minerals using mineralogically diagnostic bands at 1.4 μm, 1.9 μm, and 2 - 2.5 micron region. Atmospheric correction of the 2-μm CO2 band typically employs the same methodology applied to OMEGA data (Mustard et al., Nature 454, 2008): an atmospheric opacity spectrum, obtained from the ratio of spectra from the base to spectra from the peak of Olympus Mons, is rescaled for each spectrum in the observation to fit the 2-μm CO2 band, and is subsequently used to correct the data. Three important aspects are not considered in this correction: 1) absorptions due to water vapor are improperly accounted for, 2) the band-center of each channel shifts slightly with time, and 3) multiple scattering due to atmospheric aerosols is not considered. The second issue results in miss-registration of the sharp CO2 features in the 2-μm triplet, and hence poor atmospheric correction. This leads to the necessity to ratio all spectra using the spectrum of a spectrally "bland” region in each observation in order to distinguish features 1.9 μm. Here, we present an improved atmospheric correction method, which uses emission phase function (EPF) observations to correct for molecular opacity, and a discrete ordinate radiative transfer algorithm (DISORT - Stamnes et al., Appl. Opt. 27, 1988) to correct for the effects of multiple scattering. This method results in a significant improvement in the correction of the 2-μm CO2 band, allowing us to forgo the use of spectral ratios that affect the spectral shape and preclude the derivation of reflectance values in the data.
Dressing Courtney
Noe Dobrea Eldar Z.
Wolff Mike J.
No associations
LandOfFree
A New Method for Atmospheric Correction of MRO/CRISM Data. does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.
If you have personal experience with A New Method for Atmospheric Correction of MRO/CRISM Data., we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and A New Method for Atmospheric Correction of MRO/CRISM Data. will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-1333856