New estimation algorithm of aerosol optical thickness from space remote sensing data and its validation

Abstract

In the atmospheric correction for space remote sensing images, the aerosol optical thickness at the satellite observation time is critically needed. In this study, we proposed a new algorithm for estimating the aerosol optical thickness from satellite image data alone. In this new algorithm, the meteorological range, V, was used as a free parameter to compute the surface albedo distribution from satellite image data. The aerosol optical thickness can be easily computed from the meteorological range. The analytical approximation method for atmospheric correction and Modtran code were also utilized in our algorithm. As for the algorithm validation, the simultaneous ground and sky measurement experiments were conducted in 1996 and 1997 with ADEOS/AVNIR and LANDSAT/TM, respectively. We found that the estimation error by the proposed algorithm is less than 0.04 in terms of aerosol optical thickness. The surface albedo distribution image computed from ADEOS/AVNIR data (taken on April 24, 1997) was also presented, by using the estimated meteorological range.