SMAP-SSS: Near Real-Time Sea Surface Salinity from Satellite

Remote Sensing Systems' SMAP-SSS Level 2C V6.0 dataset provides validated, near real-time orbital swath data on global sea surface salinity (SSS) derived from NASA's Soil Moisture Active Passive (SMAP) satellite. The dataset includes derived SSS, uncertainty estimates, brightness temperature, wind speed and direction, and ancillary data on a 0.25-degree fixed Earth grid with approximately 70 km resolution. Data files, covering 98-minute orbits, are available in netCDF-4 format with about a 5-hour latency.

Use Cases

• Monitoring global ocean salinity patterns and freshwater input based on the 0.25-degree gridded sea surface salinity data.
• Studying ocean-atmosphere coupling and extreme weather events using the included wind speed and direction data.
• Validating and improving ocean circulation and climate models with near real-time, globally covered salinity observations.
• Assessing algorithm improvements in Version 6.0, such as bias mitigation at high northern latitudes and revised sun-glint flags.

Strengths

• Provides near real-time data with approximately 5-hour latency, enabling timely analysis.
• Offers global coverage approximately every 3 days due to SMAP's 1000km swath and near-polar orbit.
• Version 6.0 includes specific improvements like removal of early-mission biases and mitigation of look-angle and high-latitude biases.

Limitations

• Key metadata such as row count, column names, and specific license details are missing from all platform entries.
• The spatial resolution of approximately 70 km may be too coarse for studying fine-scale oceanic features.
• The dataset's provenance lists 'POCLOUD' as the organization on one platform, but 'Author' and definitive 'Organization' are unclear.

Provenance

Source

Remote Sensing Systems (RSS), sponsored by the NASA Ocean Salinity Science Team.

Collection Method

Derived from NASA's Soil Moisture Active Passive (SMAP) satellite using the NRT SMAP Salinity Retrieval Algorithm.

Time Range

Data collection began after the SMAP launch on January 31, 2015; specific end date is not provided.

Freshness

2026-04-09 22:26:10.705723

Geography

Global observations.