Computation of oceanlike surface thermal emission and bistatic scattering with the reduced local curvature approximation

The reduced local curvature approximation of third order (RLCA3) is a recently proposed model for rough surface scattering that matches the Kirchhoff approximation as well as the first-order and second-order small perturbation methods in appropriate limits. Predictions of bistatic scattering, thermal emission, and reflected atmospheric brightnesses from the RLCA3 model are presented in this paper through a Monte Carlo simulation process. The surfaces considered are realizations of an oceanlike spectrum and contain features ranging from 64 to 0.5 electromagnetic wavelengths. Results are compared with predictions from the commonly applied "two-scale" theory of sea emission, as well as results from a previous similar study using the small slope approximation (SSA) of Voronovich. Results show a high level of agreement between RLCA3 and SSA predicted bistatic scattering patterns, but appreciable differences in predicted surface brightnesses, particularly in the third Stokes' parameter.