NASA GRACE Project: Monthly Global Water Mass Anomalies

GRACE and GRACE-FO satellite gravity observations provide monthly grids of terrestrial water storage and ocean bottom pressure anomalies, expressed as equivalent water thickness. The data incorporates glacial isostatic adjustment and standard geophysical corrections, and is available in ASCII, netCDF, and GeoTIFF formats. Version 04 (v04) uses updated corrections and an ellipsoidal correction for Earth's shape.

Use Cases

• Modeling global groundwater depletion trends based on terrestrial water storage anomalies.
• Analyzing ocean mass changes and sea level rise from ocean bottom pressure anomaly grids.
• Monitoring large-scale hydrological extremes like droughts and floods using monthly land mass grids.
• Studying glacial isostatic adjustment and its impact on gravity field measurements.

Strengths

• Data incorporates multiple standard geophysical corrections, including geocenter, C20, C30, and glacial isostatic adjustment.
• Post-processing filters such as de-striping and spatial smoothing are applied to reduce correlated errors.
• Data is provided in multiple standard geospatial formats: ASCII, netCDF, and GeoTIFF.

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.
• Last update date is unknown; freshness unverified.

Provenance

Source

NASA GRACE and GRACE-FO satellite missions.

Collection Method

Derived from time-variable gravity observations.

Time Range

Monthly data during an unspecified timespan.

Freshness

Monthly data, but specific temporal coverage is not stated.

Geography

Global coverage.