One of the scientific objectives of the SGP97 is to investigate whether the retrieval algorithms for surface soil moisture developed at higher spatial resolution using truck- and aircraft-based passive microwave sensors can be extended to the coarser resolutions expected from satellite platforms. Although the core sensor for the SGP97 is the L-band Electronically Scanned Thinned Array Radiometer (ESTAR), brightness temperature data are also available from a spaceborne radiometer, the SSM/I aboard the DMSP satellite series. To use the SSM/I data to derive surface soil moisture, one will encounter some difficulties since it detects microwave radiation at frequencies higher than 10 GHz. Both atmosphere and vegetation cover will affect the accuracy of the retrieval. It is the objective of this paper to compare the surface soil moisture estimated from the SSM/I data with those retrieved from the ESTAR data using the same retrieval algorithm (Jackson, 1993). SSM/I data available during the SGP97 experiment were subset and processed. The SSM/I brightness temperature data will be corrected for the atmospheric effects before the retrival algorithm are applied. Radisonde profile data collected by the Atmospheric Radiation Measurement (ARM) Program sponsored by the U.S. Department of Energy will be used for the correction.
Jackson, T.J. (1993), "Measuring Surface Soil Moisture Using Passive Microwave Remote Sensing," Hydrological Processes, 7:139-152