IMOS MODIS K490: Daily Ocean Light Attenuation Coefficient from Satellite

IMOS provides a satellite-derived dataset of the diffuse attenuation coefficient at 490nm wavelength (Kd490), which indicates how light penetrates the ocean. The data is produced from multi-spectral observations by the MODIS sensor on NASA's Aqua satellite using a semi-empirical algorithm. Production of contemporary MODIS data ceased on 2024-12-26, with users directed to VIIRS instruments for newer data.

Use Cases

• Modeling primary productivity based on light attenuation in the water column.
• Monitoring coastal water quality and turbidity changes over time.
• Studying ocean biogeochemical processes that depend on light penetration.
• Calibrating and validating ocean color algorithms for satellite data.

Strengths

• Data is derived from the well-documented MODIS sensor on NASA's Aqua satellite.
• The algorithm for deriving Kd490 is described at a specific, authoritative URL (oceancolor.gsfc.nasa.gov).
• The dataset provides a clear end date for contemporary data production (2024-12-26).

Limitations

• Column-level documentation is absent; field semantics must be inferred after download.
• Row count is unknown, which may limit suitability assessment.
• The dataset's temporal coverage is not explicitly stated beyond the production end date.

Provenance

Source

Australian Ocean Data Network (AODN) via the Integrated Marine Observing System (IMOS).

Collection Method

Satellite remote sensing using the MODIS sensor on the Aqua platform, with data processed through a semi-empirical model.

Freshness

Metadata was last updated 2026-07-10 16:13:57.659130.

Geography

Likely covers ocean areas observed by the Aqua satellite, but specific spatial coverage is not detailed.