Most studies have not taken advantage of SAR’s sensitivity to soil moisture in
mapping geomorphic features. Extensive research since the 1970s (e.g. Ulaby, 1974)
has been performed on the applicability of both active and passive microwave radar
remote sensing systems for soil moisture characterization. Active sensors, including
spaceborne SAR, have the advantage over passive airborne sensors of being most
readily available to a wide-range of researchers and project application needs.