Near-surface moisture profile effects on the microwave emission of bare soils

摘要

The effects of the near- surface moisture (NSM) profile on microwave emissivity of smooth bare fields were studied using ground- based L- and X-band microwave radiometers. The results illustrate the influence of the NSM profile on microwave emissivity (volumetric soil moisture relationship of bare nonuniformly) moistened soils and the error limits when estimating the average surface moisture using a single-frequency L-band radiometer. A dual-frequency retrieval algorithm using L- and X-band radiometer data was proposed for calculating the NSM gradient.