Please Note: This dataset is retired, and is displayed for archive purposes only, and may not reflect the most updated information.

However, a newer version exists.
JPL SMAP Level 3 CAP Sea Surface Salinity Standard Mapped Image Monthly V5.0 Validated Dataset. DOI:

For Version History information click here >>

JPL SMAP Level 3 CAP Sea Surface Salinity Standard Mapped Image Monthly V4.0 Validated Dataset

5 Publications Cited this Dataset
Citation metrics available for years (2014-2022)
DescriptionThis is the PI-produced JPL SMAP-SSS V4.0 CAP, level 3, monthly mapped sea surface salinity product from the NASA Soil Moisture Active Passive (SMAP) observatory. It is based on the Combined Active-Passive (CAP) retrieval algorithm developed at JPL originally in the context of Aquarius/SAC-D and now extended to SMAP. Associated file variables include: derived SSS and wind speed from SMAP and ancillary surface salinity from HYCOM. SMAP data begins on April 1, 2015 and is ongoing, with a 1 month latency in processing and availability. L3 products are global in extent and gridded at 0.25degree x 0.25degree with an approximate spatial resolution of 60km. Improvements with this V4.0 dataset include: addition of estimated SSS uncertainty, improvement of TB correction for high latitudes, modification of the land correction range to 1000 km from coast, change of the ancillary wind source from NCEP GDAS to NCEP GFS resulting in signicant improvements in SSS retrievals near storms, extension of the range of SSS retrievals to 45 PSU, and SSS retrievals also for large inland seas. The SMAP satellite is in a near-polar orbit at an inclination of 98 degrees and an altitude of 685 km. It has an ascending node time of 6 pm and is sun-synchronous. With its 1000km swath, SMAP achieves global coverage in approximately 3 days, but has an exact orbit repeat cycle of 8 days. On board instruments include a highly sensitive L-band radiometer operating at 1.41GHz and an L-band 1.26GHz radar sensor providing complementary active and passive sensing capabilities. Malfunction of the SMAP scatterometer on 7 July for the surface roughness correction required for the surface salinity retrieval.
Questions related to this dataset? Contact
Please contact for more info.
Citation is critically important for dataset documentation and discovery. Please cite the data as follows, and cite the reference papers when it is appropriate.
Citation JPL Climate Oceans and Solid Earth group. 2018. JPL CAP SMAP Sea Surface Salinity Products. Ver. 4.0. PO.DAAC, CA, USA. Dataset accessed [YYYY-MM-DD] at

Download Citation

For more information see Data Citations and Acknowledgments.

Journal Reference Fore,A.G, S.H. Yueh, W. Tang, B.W. Stiles, and A.K. Hayashi (2016). Combined Active/Passive Retrievals of Ocean Vector Wind and Sea Surface Salinity With SMAP. IEEE TRANSACTIONS ON GEOSCIENCE AND REMOTE SENSING, VOL. 54, NO. 12. p.7396-7404. DOI: 10.1109/TGRS.2016.2601486