Independent surface volumetric soil moisture measurements were conducted using a TDR (TRACE system-Soilmoisture Incorporation). The TDR observations were obtained at the micronet, mesonet and flux stations in and around the Little Washita watershed, a total of 51
locations corresponding approximately to a coverage of 5x5 km2 resolution. The sampling sites were geo-located using a GPS. Measurements at each location were repeated every three days (the time required to visit all locations). Out of the 51 sites, 15 of them were co-located with the gravimetric observation sites. The volumetric measurements and our TDR observations were in very good agreement (correlation coefficient of 0.93). Daily soil moisture fields over the entire watershed were generated by assuming a constant average evaporation rate between measurements at each location. Spatial interpolation was conducted based on the hydraulic conductivity of the
soils. The objective of this effort was to generate a watershed-scale view of the spatial variability of soil moisture over the lower SGP97 domain, which complements the field-scale measurements conducted by other investigators. These data will enable us to evaluate the remotely-sensed soil moisture fields using a data-set independent from that used in calibration of the retrieval algorithm.