GOCE+ Geoexplore II

Data for download

Here, we provide various data sets from the GOCE mission (ESA) based on L2 TRF data. Please note:

GOCE Level 2 Product Data Handbook (GO-MA-HPF-GS-0110, 2014) - describes the input data used here.
Most of the data below is reduced for GRS80 up to degree 10 to get anomalous gradients. To get back a full gravitational signal from GOCE, use GRS80 grids provided below.
Data are provided in the Matlab binary format. Data in ASCII on request (sebera[AT]asu.cas.cz)

When using these data sets, please refer to: "Sebera, J., Šprlák, M., Novák, P., Bezděk, A., & Vaĺko, M. (2014). Iterative Spherical Downward Continuation Applied to Magnetic and Gravitational Data from Satellite. Surveys in Geophysics, 1-18" (here)

Before global use, see also GOCE Level 2 Product Data Handbook (p.49):
"The EGG_TRF_2_ gravity gradients should be used for local applications. Because of the use of (external) gravity field models to compute the long wavelength part of these gravity gradients, they should not be used for global gravity field analysis. Or at least the results from such an analysis should be interpreted with care."

This applies also to our grids as they are based on EGG_TRF_2 data!

GOCE-only gravitational gradients grids

Input: all GOCE L2 TRF data from November 2009 to October 2013
Resolution: 10 arc-min
Grid dimension: 997 x 2160 points
Grid area: [+83,-83] in geocentric latitude, [-180,180-1/6] in longitude
Reference radius: 6,621,830 m
Outliers: flagged data removed before interpolation on the MOS

GOCE-only gravitational gradients grids at satellite altitude

Txx Txy Txz Tyy Tyz Tzz
with noise X X X X X X
noise-free X X X X X X

GOCE-only gravitational gradients grids at near-ground altitude

Reference radius: 6,387,830 m (= 6,621,830 - 234,000)

FYI: These data sets are rather experimental - they contain edge effects (from a polar gap) at a few first northernmost and southernmost parallels!

Txx Txy Txz Tyy Tyz Tzz
noise-free X X X X X X

Gravitational gradients grids from geopotential models

Input: TIM-r5, DIR-r5, EGM2008, GRS80
Signal: anomalous (= full grav. signal reduced for even zonals of GRS80 up to degree 10)
Resolution: 10 arc-min
Grid dimension: the same as above
Grid area: the same as above
Reference radius: 6,621,830 m
Maximum degree: TIM-r5(220,280), DIR-r5(220,280,300), EGM2008(220,280,300), GRS80(10)
Ordering: load the variable Tij(1:997,1:2160,k) where k=1,2,3,4,5,6 stand for xx,xy,xz,yy,yz,zz

220 280 300 10
TIM-r5 X X - -
DIR-r5 X X X -
EGM2008 X X X -
GRS80 - - - X

GGs along the orbit with a constant altitude (MOS)

GOCE-only GGs: HERE (columns: xx yy zz xy xz yz) in [1/s2]
Flags: HERE (columns: xx yy zz xy xz yz)
Position data: HERE (columns: tGPS radius latitude longitude) in [s m deg deg]
GRS80 GGs up to 10: HERE (columns: xx yy zz xy xz yz) in [1/s2]
Altitude : 6,621,830 m

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