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JPL SMAP Level 3 CAP Sea Surface Salinity Standard Mapped Image Monthly V5.0 Validated Dataset

Metadata Updated: July 10, 2025

This is the PI-produced JPL SMAP-SSS V5.0 CAP, level 3, monthly mapped sea surface salinity (SSS) 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. JPL SMAP V5.0 SSS is based on the newly released SMAP V5 Level-1 Brightness Temperatures (TB). An enhanced calibration methodology has been applied to the brightness temperatures, which improves absolute radiometric calibration and reduces the biases between ascending and descending passes. The improved SMAP TB Level 1 TB will enhance the use of SMAP Level-1 data for other applications, such as sea surface salinity and winds. L3 monthly product file variables include: derived SSS with associated uncertainties 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. 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.

Access & Use Information

Public: This dataset is intended for public access and use. License: No license information was provided. If this work was prepared by an officer or employee of the United States government as part of that person's official duties it is considered a U.S. Government Work.

Downloads & Resources

Dates

Metadata Created Date April 11, 2025
Metadata Updated Date July 10, 2025

Metadata Source

Harvested from NASA Data.json

Additional Metadata

Resource Type Dataset
Metadata Created Date April 11, 2025
Metadata Updated Date July 10, 2025
Publisher NASA/JPL/SMAP;NASA/JPL/PODAAC
Maintainer
Identifier 10.5067/SMP50-3TMCS
Data Last Modified 2025-07-09
Category Earth Science
Public Access Level public
Bureau Code 026:00
Metadata Context https://project-open-data.cio.gov/v1.1/schema/catalog.jsonld
Schema Version https://project-open-data.cio.gov/v1.1/schema
Catalog Describedby https://project-open-data.cio.gov/v1.1/schema/catalog.json
Harvest Object Id 7b613ecd-9ab4-4bf1-9af6-86f9436ab325
Harvest Source Id 58f92550-7a01-4f00-b1b2-8dc953bd598f
Harvest Source Title NASA Data.json
Old Spatial "CARTESIAN",{"WestBoundingCoordinate":-180.0,"SouthBoundingCoordinate":-90,"EastBoundingCoordinate":180.0,"NorthBoundingCoordinate":90}
Program Code 026:000
Source Datajson Identifier True
Source Hash e97d4774994a8da3c9e99beae42b34b703aadf716a31d468009d96a0d9ea7221
Source Schema Version 1.1
Spatial

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