GRACE GAC: Monthly Geopotential Coefficients from Satellite Gravity Measurements

FOR EXPERT USE ONLY. This dataset contains monthly-averaged spherical harmonic coefficients representing the Earth's non-tidal geopotential field, derived from the Gravity Recovery and Climate Experiment (GRACE) mission. The data is produced by the German Research Centre for Geosciences (GFZ) and distributed by NASA. It is generated from precise measurements of distance changes between twin spacecraft in a 500 km polar orbit, using microwave ranging and accelerometer data.

Use Cases

• Modeling large-scale mass redistribution in the Earth system based on monthly gravity field variations.
• Analyzing changes in ocean bottom pressure and atmospheric mass based on non-tidal geopotential coefficients.
• Studying long-term climate signals like ice sheet mass loss or groundwater depletion from time-variable gravity data.
• Validating and improving global oceanic and atmospheric circulation models using independent gravity-derived constraints.

Strengths

• Data originates from the precise GRACE satellite mission, which uses a microwave ranging system and accelerometers.
• Produced by the authoritative German Research Centre for Geosciences (GFZ), Release 6.0.
• Provides time-variable components of the gravity field, averaged over approximately a month.

Limitations

• Description metadata is limited; actual data quality requires manual inspection after download.
• Column-level documentation is absent; field semantics must be inferred after download.
• Row count is unknown, which may limit suitability assessment.

Provenance

Source

National Aeronautics and Space Administration (NASA), German Research Centre for Geosciences (GFZ).

Collection Method

Derived from GRACE mission measurements (microwave ranging, accelerometers, GPS, star cameras) and a non-tidal oceanic and atmospheric model.

Time Range

Data is averaged over approximately a month; specific date range is not provided.

Freshness

Last updated 2026-03-13 01:40:52.536468; freshness should be verified.

Geography

Global coverage from satellite measurements.