Using Coincident MISR and AERONET data To Determine Aerosol Absorption Properties

The study of radiative forcing due to aerosol requires knowledge of aerosol absorption properties (i.e., spectral single scattering albedo). However, the determination of single scattering albedo via remote sensing can be an extremely difficult problem if the data are obtained from only a single sensor. Unless additional information is available, e.g., surface directional reflectance and aerosol particle size and amount, the retrieval problem is generally underconstrained. We investigated the use of AERONET sun photometer data in combination with coincident MISR data to provide the necessary constraits in retrieving aerosol single scattering albedo at an AERONET site. The sun photometer contributes information on aerosol amount and particle size from measurements of almucanter and principal plane sky radiance at ground level. MISR contributes multi-directional surface reflectance and top-of-atmosphere (TOA) radiance at nine distinct view angles. Together, these data sets provide the necessary boundary conditions along with sufficient aerosol information to allow a meaningful retrieval of aerosol single scattering albedo. This poster presents some results from a pilot study in which the analysis as described above was used on data obtained at a couple of select AERONET sites where significant aerosol amounts can occur, either from regional pollution events or dust storms. It is expected that the results of this and a more extensive study will be used to improve the current capability of the MISR aerosol retrieval algorithm. This work was performed at the Jet Propulsion Laboratory, California Institute of Technology under contract with the National Aeronautics and Space Administration.