Abstract
<p>The backward Monte Carlo (BMC) technique was proved to be applicable for any medium of general geometry with a volume scattering function ($\beta$) possessing time reversal invariance, and the estimator was derived for the BMC simulation of the radiative transfer processes. Then the BMC technique was used to solve the radiative transfer equation (RTE) in a two-layer (Rayleigh-scattering molecules in the upper layer and strongly forward-scattering aerosols in the lower part) spherical shell atmosphere (SSA) with a Fresnel-reflecting ocean surface (smooth or rough) at its bottom. Extensive comparisons with results of other workers were made to validate the working of the source code. Finally the results were applied to the CZCS and SeaWiFS atmospheric correction algorithms to study the effects of the Earth's curvature on the performance of the algorithms. Significant curvature effects were observed for large solar zenith angles $(\theta\sb0 > 70\sp\circ)$ in the SeaWiFS application. The employment of the SSA Rayleigh scattering calculation in replacement of that computed for a plane parallel atmosphere in the standard correction algorithms improves the accuracy of the retrieval of the water-leaving reflectance $\rho\sb{\omega}.$</p>