This paper presents progress toward a geophysical and biophysical information processor for synthetic aperture radar (SAR). This proce:~sor operates in a sequential fashion to first classify terrain according to structural attributes and then apply class-specific retrievals for geophysical and biophysical properties. Structural and electrical attributes control the rndar backscattering from terrain. Experimental data and theoretical results illustrate the
sensitivity of synthetic aperture radar to structural properties, such as surface roughness and canopy architecture, to soil moisture and to the aboveground biomass of vegetation and its moisture status