HR: 0800h
AN: A41B-0033    [Abstracts]
TI: CAFS ozone column data for validation of the AURA ozone products
AU: Shetter, R
EM: shetter@ucar.edu
AF: NCAR, 1850 Table Mesa Drive, Boulder, CO 80305 United States
AU: * Petropavlovskikh, I
EM: irina.petro@noaa.gov
AF: NOAA SSRB, 325 Broadway, Boulder, CO 80305 United States
AU: Hall, S R
EM: halls@ucar.edu
AF: NCAR, 1850 Table Mesa Drive, Boulder, CO 80305 United States
AU: Froidevaux, L
A41B-0033 AF: Jet Propulsion Laboratory, MS 183-701 4800 Oak Grove Drive, Pasadena, CA 91109 United States
AU: Bhartia, P K
EM: Pawan.Bhartia@nasa.gov
AF: NASA Goddard Space Flight Center, 8800 Greenbelt Road, Greenbelt, MD 20771 United States
AU: Kroon, M
EM: Mark.Kroon@knmi.nl
AF: KNMI, P.O. Box 201, De Bilt, NL-3730 Netherlands
AB: Highly resolved UV and Visible actinic flux measurements were taken by the CCD Actinic Flux Spectrometer (CAFS) instrument (R. Shetter, NCAR) on board of the WB-57 aircraft as part of the Aura Validation Experiment (AVE) campaign in Texas in 2004. The algorithm was developed and field-tested to derive partial ozone column products from the CAFS measurements. An intensive data set of partial ozone columns measured along the tracks of the Aura satellite has been provided for the first-round satellite validation. Preliminary analysis of the CAFS measurements revealed that small corrections to the instrument-weighted solar spectrum data were required. On its second deployment in January 2005, the CAFS instrument was flown on board of the DC-8 aircraft as part of the Polar AVE campaign. Partial ozone column data above 12 km were derived under the difficult conditions of low-sun and high ozone variability. The tropospheric ozone climatology (McPeters et al, 2004) was used for the unaccounted lower part of the ozone column below the aircraft altitude. The set of combined CAFS and climatological data was successfully used for validation of the OMI total ozone column under low-sun conditions (solar zenith angle larger than 80-degrees). Prior to the third AVE campaign in June of 2005, the CAFS instrument was modified to reduce sensitivity of the measurement to the variability of scattered light over inhomogeneous background. New look-up tables were developed and CAFS measurements have been analyzed. The preliminary results suggest that the measurement has become more sensitive to the aircraft roll and pitch movements. We will present results of the OMI total ozone column validation at different atmospheric conditions including a large range of total ozone columns and solar zenith angles, multiple altitudes, and underlying surface albedo. The MLS/Aura ozone profiles have been derived for the last three AVE campaigns. The co-incidental MLS ozone profiles were integrated above the aircraft altitude and are compared against the CAFS partial ozone column data. Results of the analysis include estimates of uncertainties in the CAFS data due to its limited sensitivity to the ozone distribution above the aircraft altitude, as well as uncertainties in the MLS products due to spatial ozone variability across the satellite footprint.
DE: 0300 ATMOSPHERIC COMPOSITION AND STRUCTURE
DE: 0360 Radiation: transmission and scattering
DE: 0394 Instruments and techniques
SC: Atmospheric Sciences [A]
MN: Fall Meeting 2005