NASA-SSH: Gridded Sea Surface Height Anomaly Maps from Satellite Altimeters

NASA provides 2-D maps of sea surface height anomaly on a 0.5-degree latitude and longitude grid, produced every 7 days. The data are derived from radar altimeter satellites including TOPEX/Poseidon, the Jason series, and Sentinel-6, beginning in October 1992 and continuing to the present. Each grid incorporates 10 days of observations, spatially averaged with a 100 km Gaussian weighting and processed to avoid mixing data from distinct ocean basins.

Use Cases

• Modeling long-term sea level rise trends based on the continuous record from 1992 to present.
• Analyzing ocean circulation and mesoscale eddies based on the weekly 0.5-degree gridded anomaly maps.
• Validating ocean and climate models using the spatially averaged sea surface height observations.
• Studying basin-specific ocean dynamics using the data segregated by connected ocean basins.

Strengths

• Long-term temporal coverage from October 1992 through the present, providing over 30 years of data.
• Standardized processing from reference mission satellites ensures consistency across the time series.
• Spatial resolution on a 0.5-degree grid with a defined 100 km averaging width for data uniformity.
• Weekly update frequency with a latency of a few weeks, offering near-real-time data availability.

Limitations

• Row count and dataset size are unknown, which may limit suitability assessment for large-scale processing.
• Column-level documentation is absent; field semantics and exact data structure must be inferred after download.
• The 10-day observation window for each 7-day grid creates temporal overlap between adjacent time steps.

Provenance

Source

National Aeronautics and Space Administration (NASA)

Collection Method

Grids are created using the NASA-SSH Along-Track Sea Surface Height from Standardized Reference Missions Version 1 dataset, applying a simple Gaussian weighted spatial average.

Time Range

October 1992 through the present

Freshness

A new grid is released approximately once per week, with a latency of a few weeks. Metadata last updated 2026-03-12.

Geography

Global ocean coverage, with data segregated by ocean basins using a defined connection table.