The Sensitivity of Multiangle Imaging to Natural Mixes of Aerosols Over Ocean

Multiangle, multispectral remote sensing observations, such as those anticipated from the Earth Observing System (EOS) Multi-angle Imaging SpectroRadiometer (MISR), can significantly improve our ability to constrain aerosol properties from space. Earlier theoretical studies explored the sensitivity of MISR to aerosol properties [Kahn et al., 1997; 19981 based on a “generic” retrieval approach; top-of-atmosphere radiances were interpreted in terms of a single, average aerosol population having unimodal size distribution and uniform composition. MISR can distinguish about a dozen groupings of particles over the natural range of physical properties: 3 sizes, 2 to 3 compositions, and spherical vs. randomly oriented nonspherical particles. This work is extended using a “climatological ” retrieval approach that asks how well MISR can distinguish among assumed, climatologically likely, external mixtures of particle types. A simplified climatology containing 5 Mixing Groups, each composed of all possible combinations of 4 particle type end-members, is abstracted from published aerosol transport model results. With the additional assumptions, the ability to distinguish among air masses containing common mixtures of atmospheric aerosols with MISR data is assessed