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An atmospheric correction algorithm over the heterogeneous surface on the emergent radiation from the top of the atmosphere is proposed. This is an atmospheric correction code for the ASTER visible channels on Terra satellite, which have a spatial resolution of 15m. Therefore, interactions of atmospheric radiation with radiation reflected by the heterogeneous surface should be accounted fox in this atmospheric correction. The surface is simulated by a checkerboard type terra-in composed of land or ocean pixels. To investigate the contribution of adjacent pixels, two additional parameters based on the diffuse transmission(a.) and reflection(B) function of the atmosphere are introduced. These parameters are independent of the surface reflection properties and thus may be used for any surf-ace. The present method was developed with reference to existing numerical results based on one-dimensional radiative transfer code. Furthermore, as vicarious calibration, skylight polarization measurements were taken by a spectro-polarimeter over the Nevada desert. The measurements indicate little absorption by aerosols in the atmosphere at wavelengths from 550nm to 700nm. Furthermore the aerosols could not be spherical particles in a poly-dispersion. (C) 2001 COSPAR. Published by Elsevier Science Ltd. All rights reserved.