DATA
TELLUS Center of Space Research Weekly 5x5 Gravity Harmonics
Please contact us if there are any discrepancies or inaccuracies found below.
DOI
10.5067/TE5DECOE01
Short Name
TELLUS_DEG_5_COEF
Description
This dataset provides weekly values of the spherical harmonic coefficients of the gravity field complete to degree and order 5, derived from satellite laser ranging up to five geodetic satellites, computed by Minkang Cheng, John Ries and Byron Tapley (2011).
This is an experimental product; the coefficients of degree 35 are of lower quality than those of degree 1 and 2 by the nature of the tracking data. The data are provided for experienced users who wish to assess the quality of the product.
The coefficients of degree 1 and 2 have clear physical interpretations. The degree 1 coefficients represent the relative position of the geocenter (the center of mass of the Earth) relative to the center of figure (defined, in practice, by the position of laser tracking stations on the surface of the Earth). The degree 2 order zero coefficient is described at http://grace.jpl.nasa.gov/data/getdata/gravityharmonics/. The degree 2 order 1 coefficients are related to the relative position of the principal figure axis of the Earth relative to the rotational axis. In the absence of external torques, those two axes would be very close [Wahr, 1987 and 1990]. However, as a consequence of excitations due to tidal and other mass redistribution within the Earth system (dominated by seasonal variations), the two axes are not completely aligned, and the rotational axis precesses around the Earths principal figure axis (causing the approximate 435 day Chandler wobble).
Version
1
Measurement
Solid Earth
› Geodetics/Gravity
› Gravity
Processing Level
2
Coverage
Global
Northernmost Latitude
89.0
Southernmost Latitude
89.0
Westernmost Longitude
180.0
Easternmost Longitude
180.0
Time Span(s)
November 5, 1992 to
May 26, 2011
Resolution
Spatial Resolution
4000.0 km (Along) x 4000.0 km (Across)
Projection

Platform/Sensor
TOPEX/POSEIDON/LRA, GRACE/GRACE ACC, GRACE/GRACE SCA, GRACE/GRACE KBR
Project
Making Earth Science Data Records for Use in Research Environments
(MEaSUREs)
Data Provider
PO.DAAC