SMOS v724 Third Mission Reprocessing: Brightness Temperature Quality and Stability

The European Space Agency (ESA) has recently published the Soil Moisture and Ocean Salinity Mission (SMOS) third mission reprocessing data, which include the changes in calibration and image reconstruction that have been made to the Level 1 Operational Processor (L1OP) version v724 during the past few years. The new L1 processor incorporates several improvements to the calibration and image reconstruction algorithms. The present article proposes a new methodology used by the SMOS team to evaluate the quality and stability of the L1 data. This is done by comparison with an ocean forward model over a well-known, sea-surface salinity stable, region. The L1 reprocessed radiometry accuracy and stability are studied in detail. The results presented here confirm the improvement on data quality expected for the new baseline algorithm. Furthermore, the remaining biases and open points are described and analyzed, establishing the basis for their improvement in following reprocessing campaigns.