IMOS OceanCurrent: Gridded Sea Level Anomaly and Velocity for Australasia

IMOS OceanCurrent provides gridded sea level anomaly (GSLA), gridded sea level (GSL), and surface geostrophic velocity data for the Australasian region. The data is produced by the Australian Ocean Data Network using optimal interpolation of detided, de-meaned altimeter and tide gauge estimates, combined with model output from Ocean Forecasting Australia Model version 3. The dataset includes both delayed mode and near real-time products, with analysis windows ranging from 14 to 30 days.

Use Cases

• Monitoring near real-time sea level anomalies based on the described GSLA mapping methodology.
• Analyzing surface geostrophic velocity fields derived from GSLA and model mean velocities.
• Studying long-term sea level trends using the gridded sea level (GSL) product which combines anomaly data with a model-derived mean sea level estimate.
• Validating ocean circulation models with the gridded velocity (UCUR, VCUR) and sea level data.

Strengths

• Includes both delayed mode and near real-time (NRT) data products, with NRT maps using an asymmetrical data window of -21 to +4 days.
• Data fusion integrates multiple sources: satellite altimeter observations, tide gauge estimates, and output from the Ocean Forecasting Australia Model version 3 (OFAM3).
• Spatial coverage is explicitly defined for the Australasian region.

Limitations

• Column-level documentation is absent; field semantics must be inferred after download.
• Row count and dataset size are unknown, which may limit suitability assessment.
• Freshness should be verified despite the listed last updated date of 2026-07-13.

Provenance

Source

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

Collection Method

Optimal interpolation of detided, de-meaned, inverse-barometer-adjusted altimeter and tide gauge estimates, combined with model output from OFAM3.

Freshness

Last updated 2026-07-13; includes near real-time (NRT) product with an analysis window up to 4 days after the map date.

Geography

Australasian region.