Near Real-Time Sea Surface Salinity from Remote Sensing Systems

The PO.DAAC is pleased to announce the release of the level 2C version 5.0 near real-time (NRT) SMAP Sea Surface Salinity (SSS) dataset from Remote Sensing Systems (RSS).

The major differences to the standard version 5.0 data product are: (1) the NRT version of the L1B SMAP antenna temperatures is used, (2) the latest 6-hourly 0.25 degree wind speed and direction are used for the ancillary wind speed and direction input, (3) the CMC SST from 2 days earlier is used for the ancillary SST input, (4) the sea-ice mask of the 3-day aggregate RSS AMSR-2 Air-Sea Essential Climate Variables (AS-ECV) data set from 2-days earlier is used for the sea-ice flag, (5) no correction for sea-ice contamination is performed, it is recommended to use only SMAP data that are classified to be within sea-ice zone 0 for open ocean scene and no sea-ice contamination.

The RSS SMAP-SSS L2C NRT V5.0 dataset and the associated technical documentation are described, discoverable, and accessible via the PO.DAAC data portal. General information regarding the SMAP mission is available from the mission website and also via PO.DAAC’s SMAP and salinity webpages.


Download data using the PODAAC Data Subscriber:

  1. Source code:
  2. Example code: podaac-data-subscriber -c SMAP_RSS_L2_SSS_NRT_V5 -d ./data/SMAP_RSS_L2_SSS_NRT_V5 --start-date 2022-07-28T00:00:00Z

Meissner, T., F.J. Wentz, and D.M. Le Vine, 2018, The Salinity Retrieval Algorithms for the NASA Aquarius Version 5 and SMAP Version 3 Releases, Remote Sensing 10, 1121, doi:10.3390/rs10071121.

Meissner, T., F. J. Wentz, A. Manaster, R. Lindsley, 2022: Remote Sensing Systems SMAP Ocean Surface Salinities [Level 2C, Level 3 Running 8-day, Level 3 Monthly], Version 5.0 validated release. Remote Sensing Systems, Santa Rosa, CA, USA. Available online at, doi: 10.5067/SMP50-2SOCS, 10.5067/SMP50-3SPCS, 10.5067/SMP50-3SMCS

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