MISR abstract
Kahn, Ralph, Pranab Banerjee, Duncan McDonald, and David J. Diner (1998). Sensitivity of multiangle imaging to aerosol optical depth and to pure-particle size distribution and composition over ocean. J. Geophys. Res., 103 (D24), 32,195-32,213.
Multiangle, multispectral remote sensing observations, such as those anticipated from the Earth Observing System (EOS) Multiangle Imaging Spectroradiometer (MISR), can significantly improve the ability to constrain aerosol properties from space. Simulations over cloud-free, calm ocean conditions were studied for pure particles with natural ranges of optical depth, particle size, and indices of refraction. According to the theoretical simulations one can retrieve column optical depth from measurements over calm ocean for all but the darkest particles, with typical size distributions and compositions, to an uncertainty of at most 0.05 or 20%, whichever is larger, even if the particle properties are poorly known. For one common particle type, soot, constraints on the optical depth over a dark ocean are very poor. The simulated measurements also allow one to distinguish spherical from nonspherical particles, to separate two to four compositional groups based on indices of refraction, and to identify three to four distinct size groups between 0.1 and 2.0 mu m characteristic radius at most latitudes. The technique is most sensitive to particle microphysical properties in the "accumulation mode" sizes, where particle scattering undergoes the transition from Rayleigh to large-particle regimes for the MISR wavelengths