ATMOSPHERIC CORRECTION OF ASTER

An atmospheric correction algorithm for operational use for the high-s patial resolution, Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) is presented. The correction is a straightforward approach relying on inputs from other satellite sensors to determine t he atmospheric characteristics of the scene to be corrected. Methods f or the solar reflective and thermal infrared (TIR) are presented separ ately. The solar-reflective approach uses a lookup table (LUT) based o n output from a Gauss-Seidel iteration radiative transfer code. A meth od to handle adjacency effects is included that relies on model output , assuming a checkerboard surface. An example of a numerical simulatio n shows that the effect of a land surface on the radiance over the oce an is stronger just off the coastal zone and decreases exponentially w ith increasing distance from the land. A typical numerical simulation is performed over the Tsukuba lake area in Japan. The TIR approach rel ies on the radiative transfer code Moderate Resolution Atmospheric Rad iance and Transmittance Model (MODTRAN), The code is run for a given s et of atmospheric conditions for multiple locations in the scene for s everal representative elevations. Pixel-by-pixel radiances are then fo und using spatial interpolation, Sensitivity analysis of the methods i ndicate that the results of the atmospheric correction,will be limited by the accuracies of the input parameters.