GRACE-FO Level-2 Monthly Geopotential Spherical Harmonics CSR Release 6.0 (RL06)

FOR EXPERT USE ONLY. This dataset contains estimates of the total month-by-month geopotential of the Earth, derived from the Gravity Recovery and Climate Experiment Follow-On (GRACE-FO) mission measurements, produced by the Center for Space Research (CSR) at University of Texas at Austin. The data are provided in spherical harmonic coefficients, averaged over approximately a month. The primary objective of the GRACE-FO mission is to obtain accurate estimates of the mean and time-variable components of the gravity field and corresponding Earth mass change variations, such as from polar ice sheets and mountain glaciers; total water storage on land (from groundwater changes in deep aquifers to changes in soil moisture and surface water); changes in deep ocean currents; and changes within the solid Earth itself, such as postglacial rebound and the impact of major earthquakes. This objective is achieved by making continuous measurements of the change in distance between twin spacecraft, co-orbiting in about 490 km altitude, near circular, polar orbit, spaced approximately 220+/-50 km apart, using a microwave ranging system. In addition to these inter-satellite range changes, the non-gravitational forces acting on each satellite are measured using a high accuracy electrostatic accelerometer. The satellite orientation and position (and timing) are precisely measured using star cameras (with three heads per satellite) and a GPS receiver. Spatial and temporal variations in the gravity field perturb the orbits (or trajectories) of the twin spacecraft differently. These differences lead to minute changes (on the order of tens of micrometers per second) in the distance between the spacecraft as they orbit the Earth. This change in distance (or range rate) 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 geopotential coefficients of an Earth gravity field model, typically on a per-month basis.

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-FO. 2019-06-10. GRACE-FO Level-2 Monthly Geopotential Spherical Harmonics CSR. Version 6. GRACEFO_L2_CSR_MONTHLY_0060. JPL. Archived by National Aeronautics and Space Administration, U.S. Government, JPL. https://doi.org/10.5067/GFL20-MC060. https://podaac-tools.jpl.nasa.gov/drive/files/allData/gracefo/docs/. GRACE-FO, JPL, 2019-06-10, GRACE-FO Level-2 Monthly Geopotential Spherical Harmonics CSR Release 6.0 (RL06), https://podaac-tools.jpl.nasa.gov/drive/files/allData/gracefo/docs/.
creator GRACE-FO
graphic-preview-description Thumbnail
graphic-preview-file https://podaac.jpl.nasa.gov/Podaac/thumbnails/GRACEFO_L2_CSR_MONTHLY_0060.jpg
identifier C1650311550-PODAAC
issued 2017-10-04
landingPage https://doi.org/10.5067/GFL20-MC060
language {en-US}
metadata_type geospatial
modified 2017-10-04
programCode {026:001}
publisher NASA/JPL/PODAAC
release-place JPL
resource-type Dataset
series-name GRACE-FO Level-2 Monthly Geopotential Spherical Harmonics CSR
source_datajson_identifier true
source_hash e9765ae5482041c558c6e4b6fa396181438d97f0
source_schema_version 1.1
spatial {"type": "Polygon", "coordinates": [[[-180.0, -89.0], [180.0, -89.0], [180.0, 89.0], [-180.0, 89.0], [-180.0, -89.0]]]}
temporal 2018-05-22T00:00:00Z/2020-11-30T00:00:00Z
theme {GRACE-FO,geospatial}
Groups
  • AmeriGEOSS
  • National Provider
  • North America
Tags
  • amerigeo
  • amerigeoss
  • ckan
  • earth-science
  • geo
  • geoss
  • gravity-gravitational-field
  • national
  • north-america
  • solid-earth
  • united-states
isopen False
license_id notspecified
license_title License not specified
maintainer Wen-Hao Li
maintainer_email wen-hao.li@jpl.nasa.gov
metadata_created 2025-11-20T11:35:45.291998
metadata_modified 2025-11-20T11:35:45.292002
notes FOR EXPERT USE ONLY. This dataset contains estimates of the total month-by-month geopotential of the Earth, derived from the Gravity Recovery and Climate Experiment Follow-On (GRACE-FO) mission measurements, produced by the Center for Space Research (CSR) at University of Texas at Austin. The data are provided in spherical harmonic coefficients, averaged over approximately a month. The primary objective of the GRACE-FO mission is to obtain accurate estimates of the mean and time-variable components of the gravity field and corresponding Earth mass change variations, such as from polar ice sheets and mountain glaciers; total water storage on land (from groundwater changes in deep aquifers to changes in soil moisture and surface water); changes in deep ocean currents; and changes within the solid Earth itself, such as postglacial rebound and the impact of major earthquakes. This objective is achieved by making continuous measurements of the change in distance between twin spacecraft, co-orbiting in about 490 km altitude, near circular, polar orbit, spaced approximately 220+/-50 km apart, using a microwave ranging system. In addition to these inter-satellite range changes, the non-gravitational forces acting on each satellite are measured using a high accuracy electrostatic accelerometer. The satellite orientation and position (and timing) are precisely measured using star cameras (with three heads per satellite) and a GPS receiver. Spatial and temporal variations in the gravity field perturb the orbits (or trajectories) of the twin spacecraft differently. These differences lead to minute changes (on the order of tens of micrometers per second) in the distance between the spacecraft as they orbit the Earth. This change in distance (or range rate) 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 geopotential coefficients of an Earth gravity field model, typically on a per-month basis.
num_resources 10
num_tags 11
title GRACE-FO Level-2 Monthly Geopotential Spherical Harmonics CSR Release 6.0 (RL06)