HR: 0830h
AN: A21C-0984    [PDF]
TI: The OMI Cloud Pressure Algorithm Based on UV Measurements
AU: * Vasilkov, A P
EM: alexander_vassilkov@ssaihq.com
AF: Science Systems and Applications Inc., 10210 Greenbelt Rd, Lanham, MD 20706 United States
AU: Joiner, J
EM: joanna.joiner@nasa.gov
AF: NASA Goddard Space Flight Center, Code 916, Greenbelt, MD 20771 United States
AU: Flittner, D E
EM: david.e.flittner@nasa.gov
AF: NASA Langley Research Center, 100 NASA Rd, Hampton, VA 23681 United States
AU: Gleason, J F
EM: gleason@redwind.gsfc.nasa.gov
AF: NASA Goddard Space Flight Center, Code 916, Greenbelt, MD 20771 United States
AU: Bhartia, P K
EM: bhartia@carioca.gsfc.nasa.gov
AF: NASA Goddard Space Flight Center, Code 916, Greenbelt, MD 20771 United States
AB: The OMI cloud pressure product is deemed "mission-essential" for OMI because the product is necessary for correction of the mission-critical total ozone product. Cloud pressure can be derived from the high frequency structure of top-of-atmosphere reflectance in the UV caused by rotational Raman scattering (RRS) in the atmosphere. RRS results in filling-in of Fraunhofer lines in the backscatter UV spectra (also known as the Ring effect). The magnitude of filling-in of the Fraunhofer lines is roughly proportional to the average number of solar photon scatterings in the atmosphere above the clouds. This property of RRS is used to deduce an effective cloud pressure. The cloud pressure algorithm retrieves the effective cloud pressure and cloud fraction using a concept of the Modified Lambert Equivalent Reflectivity (MLER). The MLER concept is used for several of the OMI algorithms including the retrieval of ozone and other trace gases. Therefore, the cloud pressure algorithm is consistent with other OMI algorithms. Details of the cloud pressure algorithm are discussed including the correction for vibrational Raman scattering in the ocean that also significantly contributes to filling-in of Fraunhofer lines in the backscatter UV spectra over pixels with thin or broken clouds. Examples of retrieving cloud pressure from GOME data are presented.
DE: 0320 Cloud physics and chemistry
DE: 0360 Transmission and scattering of radiation
DE: 3360 Remote sensing
SC: Atmospheric Sciences [A]
MN: 2003 Fall Meeting