Performance Improvements To the MISR Global Aerosol Product Algorithm

A decade of operation of the Multiangle Imaging SpectroRadiometer (MISR) on the NASA EOS Terra platform has produced a global aerosol product for that time frame that provides information on amount, absorption properties and type. An important property of the aerosol product is that its processing used a consistent, unchanging algorithm in terms of specific retrieval techniques, thresholds and aerosol model specifications. Free of algorithm modifications, the product can be studied and interpreted in a less ambiguous manner both geographically and temporally. However, various analyses have shown that some deficiencies exist which should be remedied if the product is to provide the maximum information content consistent with the multiangle, multispectral measurement approach. An extensive review of the product quality can be found at [Kahn et al., JGR doi:2010JD014601R, 2010] with additional study results being discussed in an AGU poster talk [Gaitley and Kahn, 2010]. The MISR aerosol product is currently undergoing a thorough review by the MISR project. Although not yet completed, all significant problems have been identified with proposed remedies that can be classified as basic upgrades in technique. Particular problems that are being addressed include retrieved optical depths that are biased low when the land aerosol amount is high and optical depths biased high when the ocean aerosol amount is low. Later issues to be addressed will concern the aerosol model database and selection criteria. The poster will show examples of improved performance of the provisional upgraded algorithm through a comparison of results with the current operational version. The emphasis will be on demonstrating the resolution or mitigation of the particular problems mentioned above. This work was performed at the Jet Propulsion Laboratory, California Institute of Technology under contract with the National Aeronautics and Space Administration.