Aquarius: Seasonal Ascending Rain-Flagged Sea Surface Salinity

Aquarius Level 3 data provides seasonal, rain-flagged sea surface salinity (SSS) measurements at a 1-degree spatial resolution. The dataset is derived from ascending passes of the Aquarius/SAC-D satellite, a joint NASA and CONAE mission, using a combination of three radiometers and a scatterometer for surface roughness correction. It represents version 5.0 of the processed, gridded standard mapped image product.

Use Cases

• Monitoring seasonal changes in global ocean salinity based on gridded 1-degree resolution data.
• Studying ocean surface roughness corrections using scatterometer backscatter measurements at 1.26 GHz.
• Analyzing ascending-pass-only satellite retrievals to isolate diurnal or orbital pass effects.
• Investigating freshwater input from rainfall using the rain-flagged salinity product.

Strengths

• Provides data from a dedicated satellite mission (Aquarius/SAC-D) with a described instrument configuration, including three radiometers at specific incidence angles (29°, 38°, 46°).
• Includes corrections for surface roughness via a co-located scatterometer with a 390 km swath.
• Represents a specific, versioned product (V5.0) for a defined temporal composite (Seasonal) and pass type (Ascending).

Limitations

• Critical metadata is missing: no row/record count, file size, or specific column names are provided in any source.
• Conflicting 'last updated' dates exist between platforms (2015 on NASA Earthdata vs. 2026 on Data.gov), casting doubt on data maintenance and provenance.
• Spatial resolution is coarse (1 degree), which may limit analysis of mesoscale or coastal ocean features.

Provenance

Source

National Aeronautics and Space Administration (NASA) and Comisión Nacional de Actividades Espaciales (CONAE)

Collection Method

Satellite remote sensing via the Aquarius instrument on the AQUARIUS/SAC-D platform, processed to Level 3 standard mapped images.

Freshness

2026-03-13 17:27:20.189002

Geography

Global ocean coverage with a total cross-track swath of 370 km for the radiometers.