GRACE NON-TIDAL ATMOSPHERE GEOPOTENTIAL COEFFICIENTS GFZ RELEASE 6.0 GAA

FOR EXPERT USE ONLY. This dataset contains estimates of geopotential field derived from the Gravity Recovery and Climate Experiment (GRACE) mission measurements and a non-tidal atmospheric model produced by the German Research Centre for Geosciences (GFZ). The data are in spherical harmonics averaged over approximately a month. The primary objective of the GRACE mission is to obtain accurate estimates of the mean and time-variable components of the gravity field variations. This objective is achieved by making continuous measurements of the change in distance between twin spacecraft, co-orbiting in about 500 km altitude, near circular, polar orbit, spaced approximately 200 km apart, using a microwave ranging system. In addition to these range change, the non-gravitional forces are measured on each satellite using a high accuracy electrostatic, room-temperature accelerometer. The satellite orientation and position (and timing) are precisely measured using twin star cameras and a GPS receiver, respectively. Spatial and temporal variations in the gravity field affect the orbits (or trajectories) of the twin spacecraft differently. These differences are manifested as changes in the distance between the spacecraft, as they orbit the Earth. This change in distance is reflected in the time-of-flight of microwave signals transmitted and received nearly simultaneously between the two spacecraft. The change in this time of fight is continuously measured by tracking the phase of the microwave carrier signals. The so called dual-one-way range change measurements can be reconstructed from these phase measurements. This range change (or its numerically derived derivatives), along with other mission and ancillary data, is subsequently analyzed to extract the parameters of an Earth gravity field model.

Data and Resources

Field Value
accessLevel public
bureauCode {026:00}
catalog_@context https://project-open-data.cio.gov/v1.1/schema/catalog.jsonld
catalog_@id https://data.nasa.gov/data.json
catalog_conformsTo https://project-open-data.cio.gov/v1.1/schema
catalog_describedBy https://project-open-data.cio.gov/v1.1/schema/catalog.json
citation GRACE. 2018-08-31. GRACE NON-TIDAL ATMOSPHERE GEOPOTENTIAL COEFFICIENTS GFZ (GAA). Version 6.0. GRACE_GAA_L2_GRAV_GFZ_RL06. JPL PO.DAAC. Archived by National Aeronautics and Space Administration, U.S. Government, GFZ. https://doi.org/10.5880/GFZ.GRACE_06_GAA. https://podaac-tools.jpl.nasa.gov/drive/files/allData/grace/docs/. GRACE, GFZ, 2018-08-31, GRACE NON-TIDAL ATMOSPHERE GEOPOTENTIAL COEFFICIENTS GFZ RELEASE 6.0 GAA, https://podaac-tools.jpl.nasa.gov/drive/files/allData/grace/docs/.
creator GRACE
graphic-preview-description Thumbnail
graphic-preview-file https://podaac.jpl.nasa.gov/Podaac/thumbnails/GRACE_GAA_L2_GRAV_GFZ_RL06.jpg
identifier C1674784944-PODAAC
issued 2018-08-06
landingPage https://doi.org/10.5880/GFZ.GRACE_06_GAA
language {en-US}
metadata_type geospatial
modified 2018-08-06
programCode {026:001}
publisher NASA/JPL/PODAAC
release-place JPL PO.DAAC
resource-type Dataset
series-name GRACE NON-TIDAL ATMOSPHERE GEOPOTENTIAL COEFFICIENTS GFZ (GAA)
source_datajson_identifier true
source_hash 3565635d6b83639566ad68a3128d67f91922edb8
source_schema_version 1.1
spatial {"type": "Polygon", "coordinates": [[[-180.0, -88.0], [180.0, -88.0], [180.0, 88.0], [-180.0, 88.0], [-180.0, -88.0]]]}
temporal 2002-04-05T00:00:00Z/2017-07-01T00:00:00Z
theme {GRACE,geospatial}
Groups
  • AmeriGEOSS
  • National Provider
  • North America
Tags
  • amerigeo
  • amerigeoss
  • ckan
  • earth-science
  • geo
  • geoss
  • gravity-gravitational-field
  • national
  • north-america
  • ocean-pressure
  • oceans
  • solid-earth
  • united-states
isopen False
license_id notspecified
license_title License not specified
maintainer Christopher Finch
maintainer_email Chris.Finch@jpl.nasa.gov
metadata_created 2025-11-20T11:48:25.111281
metadata_modified 2025-11-20T11:48:25.111286
notes FOR EXPERT USE ONLY. This dataset contains estimates of geopotential field derived from the Gravity Recovery and Climate Experiment (GRACE) mission measurements and a non-tidal atmospheric model produced by the German Research Centre for Geosciences (GFZ). The data are in spherical harmonics averaged over approximately a month. The primary objective of the GRACE mission is to obtain accurate estimates of the mean and time-variable components of the gravity field variations. This objective is achieved by making continuous measurements of the change in distance between twin spacecraft, co-orbiting in about 500 km altitude, near circular, polar orbit, spaced approximately 200 km apart, using a microwave ranging system. In addition to these range change, the non-gravitional forces are measured on each satellite using a high accuracy electrostatic, room-temperature accelerometer. The satellite orientation and position (and timing) are precisely measured using twin star cameras and a GPS receiver, respectively. Spatial and temporal variations in the gravity field affect the orbits (or trajectories) of the twin spacecraft differently. These differences are manifested as changes in the distance between the spacecraft, as they orbit the Earth. This change in distance is reflected in the time-of-flight of microwave signals transmitted and received nearly simultaneously between the two spacecraft. The change in this time of fight is continuously measured by tracking the phase of the microwave carrier signals. The so called dual-one-way range change measurements can be reconstructed from these phase measurements. This range change (or its numerically derived derivatives), along with other mission and ancillary data, is subsequently analyzed to extract the parameters of an Earth gravity field model.
num_resources 10
num_tags 13
title GRACE NON-TIDAL ATMOSPHERE GEOPOTENTIAL COEFFICIENTS GFZ RELEASE 6.0 GAA