10.2312/GFZ.B103-00228
Klokocnik, Jaroslav
Jaroslav
Klokocnik
https://orcid.org/0000-0003-1034-8089
Reigber, Christoph
Christoph
Reigber
https://orcid.org/0000-0001-9036-1499
Schwintzer, Peter
Peter
Schwintzer
Wagner, Carl A.
Carl A.
Wagner
Kostelecký, Jan
Jan
Kostelecký
Evaluation of pre-CHAMP gravity models GRIM5-S1 and GRIM5-C1 with Satellite Crossover Altimetry
GFZ German Research Centre for Geosciences
2000
Report
2000
en
6 MB
PDF
CC-BY 4.0
Scientific Technical Report STR; 00/22
Scientific Technical Report STR; 00/22
The new GFZ/GRGS gravity field models GRIM5-S1 and Cl, current initial
models for the CHAMP mission, have been compared with other recent models (JGM 3, EGM 96) for radial accuracy
(by means of latitude lumped coefficients) in computations on altimetry satellite orbits. The basis for accuracy
judgements are extensive (multi-year) averages of crossover sea height differences from Geosat and ERS 1/2 missions.
These data are fully independent of the data used to develop these gravity models. We tested how well these observed
differences in all the world's oceans agree with projections of the same errors from the scaled covariance matrix of
their harmonic geopotential coefficients. It was found that the tentative (model) scale factor of 5 for the formal
standard deviations of the harmonic coefficients of the new GRIM fields is justified, i.e. the accuracy estimates,
provided together with the geopotential coefficients, are realistic.