Soil moisture (water-content) assessment by an airborne scatterometer: TheChernobyl disaster area and the Negev desert

Soil water content is an important component that influences meso- and micr oscale processes. The agricultural capacity of a site is directly affected by soil water content and it is especially important in a-id regions. In te mperate and humid regions, soil water content is important in determining f lood risks. Environmentally, soil water content will influence the risk of carrying pollutants through the soil. For these reasons, a scatterometer wa s developed as a remote sensor for mapping soil water content. The scattero meter is frequency modulated ruing a continuous wave. This scatterometer op erates at nadir with a wide antenna diagram of 10 degrees. Measurements wer e conducted in two environment with different implications. The first was i n the Chernobyl nuclear disaster nr-ea and the second in the Negev desert. Results show? a good correlation between soil water content and the amplitu de of the re turned signal measured by the scatterometer. Thus, the scatter ometer provides art efficient tool for mapping soil water content. The long wavelength (P-band) of lambda=68 cm makes this scatterometer more sensitiv e to soil teeter content and less affected by surface roughness than scatte rometers operating at shorter wavelengths. (C) Elsevier Science Inc., 2000.