Abstract: In passive microwave remote sensing of soil moisture, the tau-omega (t-?) model has often been used to provide soil moisture estimates at a spatial scale representative of the satellite footprint dimensions. For modeling simplicity, model parameters such as the single scattering albedo (?) and vegetation opacity (t) that go into the geophysical inversion process are often assumed to be independent of polarizations. Although this absence of polarization dependence can often be justified in spe…