SMAP data sets, accessible through the NASA National Snow and Ice Data Center Distributed Active Archive Center (NSIDC DAAC), are impacted by the following change. As of Thursday, 30 January 2020, NASA Goddard Space Flight Center’s Global Modeling and Assimilation Office has implemented an upgrade to the GEOS Forward Processing (FP) system, which provides ancillary data used in generating SMAP data products. In particular, the GEOS FP soil temperature values used in the SMAP Level-2 and -3 soil moisture retrieval algorithm are somewhat different after the system upgrade, and these differences will propagate into SMAP soil moisture retrievals going forward. Changes in other GEOS FP near-surface fields that are used in SMAP processing may also result in minor changes in SMAP Level-1 brightness temperatures, Level-3 freeze-thaw products, and Level-4 soil moisture and carbon products. The SMAP Project Team has begun an assessment of the impact of the GEOS FP upgrade on the SMAP data products and will communicate the results of the assessment as soon as possible to SMAP users.
Access to the SMAP data page at the NSIDC DAAC: https://nsidc.org/data/smap