HR: 1340h
AN: A23A-0877    [Abstracts]
TI: Validation of the OMI multi-wavelength aerosol product
AU: * Braak, R
EM: braak@knmi.nl
AF: KNMI, PO Box 201, De Bilt, 3730 AE, Netherlands
AU: Veihelmann, B
EM: veihelma@knmi.nl
AF: KNMI, PO Box 201, De Bilt, 3730 AE, Netherlands
AU: Veefkind, P
EM: veefkind@knmi.nl
AF: KNMI, PO Box 201, De Bilt, 3730 AE, Netherlands
AU: Torres, O
EM: torres@qhearts.gsfc.nasa.gov
AF: Joint Center for Earth Systems Technology, University of Maryland, Baltimore County, Baltimore, MD 21250, United States
AU: Torres, O
EM: torres@qhearts.gsfc.nasa.gov
AF: NASA Goddard Space Flight Center, Mail Code 613.3, Greenbelt, MD 20771, United States
AU: Levelt, P
EM: levelt@knmi.nl
AF: KNMI, PO Box 201, De Bilt, 3730 AE, Netherlands
AB: One of the science goals of the Ozone Monitoring Instrument (OMI) on board of EOS-Aura is to help answer the question "What is the role of aerosols in climate change?" To this end, properties such as the aerosol UV absorbing index and, for cloud-free scenes, aerosol optical thickness are derived from the near-ultraviolet and visible spectra that are measured by OMI. The application of ultraviolet spectra is especially useful since in that wavelength range, retrievals are less sensitive to surface albedo assumptions and the presence of aerosols may be quantified even above or within clouds. One of the OMI aerosol products makes use of the multi-wavelength algorithm. This algorithm extends the wavelength range employed by the proven TOMS algorithm to visible wavelengths including the 477-nm absorption band of the O₂-O₂ collision complex that is sensitive to aerosol altitude. This product has been provisionally released and is currently being validated. In this presentation, results of comparisons, both qualitative and quantitative, with AERONET ground-based observations will be shown, as well as results of comparisons with other satellite sensors, especially those on A-Train satellites, such as MODIS and PARASOL. The pixel-wise correlation between OMI and A-Train sensors, varies from good to relatively poor, depending on the region and the prevalent aerosol type. Comparisons with ground-based observations point out problematic areas over land and give clues for further improvement of the algorithm and its cloud-screening procedure. Over oceans, quantitative comparisons with Aqua/MODIS and PARASOL are very good. Monthly regional averages generally show the same seasonal trends as similar observations from MODIS and MISR and prove the worth of the OMI multi-wavelength aerosol algorithm.
DE: 0305 Aerosols and particles (0345, 4801, 4906)
DE: 3311 Clouds and aerosols
DE: 3360 Remote sensing
SC: Atmospheric Sciences [A]
MN: 2007 Fall Meeting