A Partial Coherent Physical Model of Third and Fourth Stokes Parameters of Sastrugi Snow Surfaces over Layered Media with Rough Surface Boundary Conditions of Con- Ical Scattering Combined with Vector Ra- Diative Transfer Theory

In this paper, a partial coherent approach is used to study the third and fourth Stokes parameters in passive microwave remote sensing of Sastrugi snow surface over layered snow structures. The incoherent part of the model consists of using radiative transfer theory for the snow layers. The coherent part of the model is using numerical solutions of Maxwell equations to derive the bistatic scattering and transmission coefficients of conical scattering by sastrugi surfaces which have large heights and large slopes. We then use the rough surface boundary conditions of conical scattering from the coherent part, in the incoherent radiative transfer equations. The radiative transfer equations are then solved iteratively that includes multiple interactions between the layered structures and the rough surfaces. Simulation results indicate that large third and fourth Stokes parameters are obtained because of the coupling of large angle transmissions of the rough surfaces with the internal reflections of layered structures. The partial coherent approach also eliminates the coherent interference patterns in angular variations from multiple reflections of layer boundaries that were present in the fully coherent approach.