Validation of Single Scattering Approximation for an Atmospheric Correction on Satellite Data in the Visible Region

Abstract

For an atmospheric correction on satellite data, validation of single scattering approximation is examined at 0.4, 0.5, and 0.6μm, using the model atmosphere bounded by the Lambert surface. The LOWTRAN 5 model atmosphere is adopted in mid-latitude in summer. The results of single scattering approximation are compared with those of multiple scattering in homogeneous and inhomogeneous atmosheres. It was found from the computations that in a clear condition, the upward radiance in an inhomogeneous atmosphere using multiple scattering approximation method would be estimated by multiplying some empirical factors on that derived by single scattering approximation method. Furthermore, the upward radiance with single scattering approximation method considering upto four scattering modes in radiative transfer processes shows small differences in comparison with that of single scattering method considering all modes until convergence. Thus the upward radiance would simply be evaluated using the single scattering approximation method upto four modes. Whereas in a hazy condition, the above factors exhibit a strong dependence on observational nadir angles.They are affected by the surface albedo as well. Furthermore, an optical characteristics of aerosols is one of the essential factors to perform atmospheric correction. Therefore single scattering approximation method would be quite crude.