Skip to main content

Description

This is a level 4 product on a 0.25-degree spatial and 4-day temporal grid. The product is derived from the level 2 swath data of three satellite missions: the Aquarius/SAC-D, Soil Moisture Active Passive (SMAP) and Soil Moisture and Ocean Salinity (SMOS) using Optimal Interpolation (OI) with a 7-day decorrelation time scale. The product offers a continuous record from August 28, 2011 to present by concatenating the measurements from Aquarius (September 2011 - June 2015) and SMAP (April 2015 present). ESAs SMOS data was used to fill the gap in SMAP data between June and July 2019, when the SMAP satellite was in a safe mode. The two-month overlap (April - June 2015) between Aquarius and SMAP was used to ensure consistency and continuity in data record. The product covers the global ocean, including the Arctic and Antarctic in the areas free of sea ice, but does not cover internal seas such as Mediterranean and Baltic Sea. In-situ salinity from Argo floats and moored buoys are used to derive a large-scale bias correction and to ensure consistency and accuracy of the OISSS dataset. This dataset is produced by the International Pacific Research Center (IPRC) of the University of Hawaii at Manoa in collaboration with the Remote Sensing Systems (RSS), Santa Rosa, California. More details can be found in the users guide.

Product Summary

Platforms
SMAP ,
SAC-D ,
SMOS
Instruments
SMAP L-BAND RADIOMETER ,
AQUARIUS_SCATTEROMETER
Spatial Extent

N: 90 S: -90 E: 180 W: -180

Spatial Resolution
0.25 Decimal Degrees x 0.25 Decimal Degrees
Location
GLOBAL
Coordinate System
CARTESIAN
Granule Spatial Representation
CARTESIAN
Temporal Extent
2011-08-24
Data Partner
Physical Oceanography Distributed Active Archive Center, Jet Propulsion Laboratory, NASA (NASA/JPL/PODAAC) ,
International Pacific Research Center, School of Ocean and Earth Science and Technology, University of Hawaii (UHI/SOEST/IPRC)
Concept ID
C2095055342-POCLOUD
Data State
COMPLETE
Number of Files/Granules
999
Processing Level
4
Published
Updated
Science Keywords
Salinity

Citation

Citation is critically important for dataset documentation and discovery. This dataset is openly shared, without restriction, in accordance with the EOSDIS Data Use and Citation Guidance.

Copy Citation

IPRC/SOEST, U. of H. (2021). Multi-Mission Optimally Interpolated Sea Surface Salinity 7-Day Global Dataset V1 [Data set]. NASA Physical Oceanography Distributed Active Archive Center. https://doi.org/10.5067/SMP10-4U7CS Date Accessed: 2026-04-05

Documents

Variables

The table below lists the variables contained within a single granule for this dataset. Variables often contain observed or derived geophysical measurements collected from a variety of sources, including remote sensing instruments on satellite and airborne platforms, field campaigns, in situ measurements, and model outputs. The terms variable, parameter, scientific data set, layer, and band have been used across NASA’s Earth science disciplines; however, variable is the designated nomenclature in NASA’s Common Metadata Repository (CMR). Variable metadata attributes such as Name, Description, Units, Data Type, Fill Value, Valid Range, and Scale Factor allow users to efficiently process and analyze the data. The full range of attributes may not be applicable to all variables. Additional information on variable attributes is typically available in the data, user guide, and/or other product documentation.

For questions on a specific variable, please use the Earthdata Forum.

Name Description Units Data Type Fill Value Valid Range Scale Factor Offset
latitude latitude degrees_north float N/A -90 to 90 1 N/A
longitude longitude degrees_east float N/A -180 to 180 1 N/A
sss sea surface salinity 1e-3 float -9999 0 to 45 1 N/A
sss_uncertainty estimated empirical uncertainty of multi-mission OISSS 1e-3 float -9999 0 to 45 1 N/A
time center day of a time period over which satellite Level 2 SSS data have been collected for OISSS analysis Days since 2010-12-31T00:00:00Z float N/A N/A 1 N/A
You're viewing 5 of 5