Field data from the Soil Moisture Active Passive Validation Experiment 2015 (SMAPVEX15) validation campaign are now available at the National Snow and Ice Data Center Distributed Active Archive Center (NSIDC DAAC).
The new data set contains in situ gravimetric and volumetric soil moisture, bulk density, and soil temperature measurements. Visit the product page for details:
SMAPVEX15 Probe-Based In Situ Soil Moisture Data, Version 1
To access all SMAP validation data and documentation, see the SMAP Validation Data web page.