GRACE Monthly Mass Grids - Ocean EOFR

NASA/GRACE/MASS_GRIDS/OCEAN_EOFR
Dataset Availability
2002-12-31T00:00:00Z–2016-12-10T00:00:00Z
Dataset Provider
Earth Engine Snippet
ee.ImageCollection("NASA/GRACE/MASS_GRIDS/OCEAN_EOFR")
Tags
crs gfz grace gravity jpl mass nasa ocean tellus water

Description

GRACE Tellus Monthly Mass Grids provides monthly gravitational anomalies relative to a 2004-2010 time-mean baseline. The data contained in this dataset are units of "Equivalent Water Thickness" which represent the deviations of mass in terms of vertical extent of water in centimeters. See the provider's Monthly Mass Grids Overview for more details.

This dataset is a filtered version of the GRACE Tellus (GRCTellus) Ocean dataset. The 'EOFR' bottom pressure (OBP) grids are obtained by projecting the data from the regular GRC Ocean grids product onto the Empirical Orthogonal Functions (EOFs) of the Ocean Model for Circulation and Tides (OMCT). This effectively filters out signals in the GRACE data that are inconsistent with the physics and OBP variations in the OMCT ocean model.

The EOFR filtered reconstructed OBP fields agree better with radar altimetric sea surface height, reduce leakage around ice sheets and glaciers, and reduce noise in the mid latitudes where OBP variability is lower. (Chambers and Willis, 2010)

Note

  • The GRCTellus Ocean datasets are optimized to examine regional ocean bottom pressure, but NOT intended to be spatially averaged to determine global mean ocean mass.

Bands

Resolution
111320 meters

Bands

Name Units Min Max Description
lwe_thickness_csr cm -18.46* 12.29*

Equivalent liquid water thickness in centimeters calculated by CSR.

lwe_thickness_gfz cm -15.37* 14.56*

Equivalent liquid water thickness in centimeters calculated by GFZ.

lwe_thickness_jpl cm -16.59* 11.7*

Equivalent liquid water thickness in centimeters calculated by JPL.

* estimated min or max value

Image Properties

Image Properties

Name Type Description
CSR_END_TIME DOUBLE

End date in milliseconds of spherical harmonics solution from CSR.

CSR_START_TIME DOUBLE

Start date in milliseconds of spherical harmonics solution from CSR.

GFZ_END_TIME DOUBLE

End date in milliseconds of spherical harmonics solution from GFZ.

GFZ_START_TIME DOUBLE

Start date in milliseconds of spherical harmonics solution from GFZ.

JPL_END_TIME DOUBLE

End date in milliseconds of spherical harmonics solution from JPL.

JPL_START_TIME DOUBLE

Start date in milliseconds of spherical harmonics solution from JPL.

Terms of Use

Terms of Use

All NASA-produced data from the GRACE mission is made freely available for the public to use. When using any of the GRCTellus data, please add an acknowledgment: "GRACE land are available at https://grace.jpl.nasa.gov, supported by the NASA MEaSUREs Program." and cite with the citations provided.

Citations

Citations:
  • D.P. Chambers. 2012. GRACE MONTHLY OCEAN MASS GRIDS NETCDF RELEASE 5.0. Ver. 5.0. PO.DAAC, CA, USA. Dataset accessed [YYYY-MM-DD] at doi:10.5067/TEOCN-0N005.

  • Chambers, D.P. and J.A. Bonin: Evaluation of Release 05 time-variable gravity coefficients over the ocean. Ocean Science 8, 859-868, 2012. doi:10.5194/os-8-859-2012.

  • Chambers D.P. and J. K. Willis: A Global Evaluation of Ocean Bottom Pressure from GRACE, OMCT, and Steric-Corrected Altimetry. J. of Oceanic and Atmosph. Technology, vol 27, pp 1395-1402, 2010.. doi:10.1175/2010JTECHO738.1

DOIs

Explore with Earth Engine

Code Editor (JavaScript)

var dataset = ee.ImageCollection('NASA/GRACE/MASS_GRIDS/OCEAN_EOFR')
                  .filter(ee.Filter.date('2016-08-01', '2016-08-30'));
var equivalentWaterThicknessCsr = dataset.select('lwe_thickness_csr');
var equivalentWaterThicknessCsrVis = {
  min: -10.0,
  max: 10.0,
};
Map.setCenter(6.746, 46.529, 1);
Map.addLayer(
    equivalentWaterThicknessCsr, equivalentWaterThicknessCsrVis,
    'Equivalent Water Thickness CSR');
Open in Code Editor