A DUAL-VIEW OPTIMAL ESTIMATION SCHEME FOR AEROSOL RETRIEVAL USING AATSR DATA

The differing path lengths of the forward and nadir views of the Advanced Along-Track Scanning Radiometer (AATSR) are used to separate the contributions from aerosol scattering and surface reflectance in the observed top-of-atmosphere (TOA) radiance. This poster presents an effort to extend the Oxford-RAL retrieval of Aerosols and Clouds (ORAC) scheme used by the GRAPE and GlobAEROSOL projects [1], which currently uses data from the nadir viewing geometry only, to take advantage of the dual-view capabilities AATSR offers. The new algorithm uses optimal estimation to retrieve aerosol optical depth at 550 nm, effective radius and surface albedo at 550 nm for both forward and nadir viewing geometries (with the spectral shape of the surface constrained by a model based on Cox and Munk statistics [2,3] for the sea, and MODIS data [4] for the land)