The SMAP in situ soil moisture sensor testbed: Comparing in situ sensors for satellite validation

In order to validation soil moisture products from remote sensing platforms, an accurate and verified ground dataset is necessary. However, the diversity of in situ soil moisture networks makes the aggregation of available data difficult because of the difference in quality and accuracy. A testbed was initiated as part of the Soil Moisture Active Passive satellite mission to intercompare the current and emerging in situ soil moisture technologies. The testbed is located in Marena, Oklahoma, USA, in a large grass pasture. Four base stations were installed in May 2010 with more sensors to be added as they are manufactured. Included in the testbed are the new COSMOS soil moisture instruments and GPS receivers which are emerging technologies measuring soil moisture on a large scale. Regular soil moisture and vegetation sampling will be conducted to check the accuracy and representativeness of the sensors.