HR: 10:45h
AN: A12D-02    [Abstracts]
TI: Determination of Atmospheric CO2 from AIRS Spectra by the Method of Vanishing Partial Derivatives
AU: * Chahine, M T
EM: moustafa.t.chahine@jpl.nasa.gov
AF: Jet Propulsion Laboratory, 4800 Oak Grove Drive, Pasadena, CA 91109 United States
AU: Barnet, C
EM: chris.barnet@noaa.gov
AF: NOAA NESDIS, 5200 Auth Road, Camp Spring, MD 207846 United States
AU: Olsen, E T
EM: edward.t.olsen@jpl.nasa.gov
AF: Jet Propulsion Laboratory, 4800 Oak Grove Drive, Pasadena, CA 91109 United States
AU: Chen, L
EM: luke.chen@jpl.nasa.gov
AF: Jet Propulsion Laboratory, 4800 Oak Grove Drive, Pasadena, CA 91109 United States
AU: Maddy, E
EM: eric.maddy@noa.gov
AF: QSS Group, Inc., 5200 Auth Road, Camp Spring, MD 207846 United States
AB: We present a general method for the determination of minor gases in the troposphere from high spectral resolution observations. In this method, we make use of a general property of the total differential of multi-variable functions to separate the contributions of each individual minor gas. We have applied this method to derive the mixing ratio of carbon dioxide using on-orbit measurements from the Atmospheric Infrared Sounder (AIRS) currently flying on the NASA Aqua Mission. We validate our results against the aircraft observations of carbon dioxide obtained by H. Matsueda et al over the western Pacific. We show that AIRS results track Matsueda's flask measurements with an agreement of 0.43 - 1.20 ppmv. The AIRS instrument is a cross-track scanning grating spectrometer that covers the 3.7 to 15 micrometer spectral range with 2378 channels at a nominal spectral resolving power of 1200 and a 13.5 km field of view at nadir. After 3 years in space, AIRS has demonstrated a stability of 10 milli-Kelvin per year with a spectral accuracy of the center frequency of 2 parts per million. The coincidence of 'cloud-free' AIRS footprints with Matsueda observations is rare. Using the Advanced Microwave sounding Unit (AMSU) in combination with AIRS allows removing the effect of clouds and retrieval of atmospheric temperature, water vapor and minor gases can be made in the presence of cloud. This capability permits comparison between a large number of AIRS/AMSU footprints and the Matsueda measurements under the flight path of AIRS.
DE: 1855 Remote sensing (1640)
SC: Atmospheric Sciences [A]
MN: Fall Meeting 2005