Improvements in High Resolution Gravity Field Modeling at GFZ

  • Th. Gruber
  • M. Anzenhofer
  • M. Rentsch
  • P. Schwintzer
Part of the International Association of Geodesy Symposia book series (IAG SYMPOSIA, volume 117)

Abstract

Global high-degree gravity field models, complete to degree 360 have been computed by two different groups. While the Ohio State University approach is based since many years on a combination of complete long wavelength normal equations with a diagonal system for the high degrees, at GFZ the block-diagonal least squares technique was used for estimation of the complete coefficient series. For the new GFZ models as well as for the new American EGM96 model, an improved strategy based on a combination of complete normals for the long wavelengths, with block-diagonals for the high frequencies was implemented. In addition some new mean gravity data for Russia, better information from altimetry over the oceans, and an improved data preparation scheme was introduced. Different new 360 gravity field solutions were computed by this scheme. Comparisons to the OSU91A model and the GFZ95A model show some improvements with respect to the previous solutions, which can be addressed nearly completely to the new estimation technique. Further studies are required for the combination of different data types (e.g gravity anomalies and geoid heights) in one solution, and for a further improvement of the modeling towards a complete and strong least squares solution for the 360 spherical harmonic series.

Preview

Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.

References

  1. Bosch W. (1993); A Rigorous Least Squares Combination of Low and High Degree Spherical Harmonics; Paper pres. at IAG General Meeting, Session 11, Part D-Problems and Results of large Scale Geoid Determination; Beijing, ChinaGoogle Scholar
  2. Feron R., De Ruijter W., Van Leeuwen P. (1996); The Mean Sea Surface Topography from Altimeter Observations of Horizontal Eddy Stress; Paper submitted to Journal of Geophysical ResearchGoogle Scholar
  3. Gruber Th., Anzenhofer M., Rentsch M. (1996); The 1995 GFZ High Resolution Gravity Model; in: Global Gravity Field and Its Temporal Variations, Proceedings of IAG Symposium No. 116; ed: Rapp, Cazenave, Nerem; Springer Verlag, Berlin.Google Scholar
  4. Lemoine F.G. (1996); Development of NASA-GSFC/DMA Geopotential Model; Paper pres. at Gravity, Geoid and Marine Geodesy Symposium, TokyoGoogle Scholar
  5. Pavlis N.K. (1988); Modeling and Estimation of a Low Degree Geopotential Model from Terrestrial Gravity Data; Ohio State University, Department of Geodetic Science and Surveying, Report No. 386, Columbus, OhioGoogle Scholar
  6. Pavlis N.K., Chan J.C., Lerch F.J. (1996); Alternative Estimation Techniques for Global High-Degree Gravity Modeling; in: Global Gravity Field and Its Temporal Variations, Proceedings of IAG Symposium No. 116; ed: Rapp, Cazenave, Nerem; Springer Verlag, Berlin.Google Scholar
  7. Rapp R.H. (1989); The Treatment of Permanent Tidal Effects in the Analysis of SatelliteAltimeter Data for Sea Surface Topography; Manuscripta Geodaetica, 14, 368–372Google Scholar
  8. Rapp R.H., Kim J.H. (1990); The Development of the July 1x1 Degree and 30’x30’Terrestrial Mean Free-Air Anomaly Data Base; Ohio State University, Department of Geodetic Science and Surveying, Report No. 403, Columbus, OhioGoogle Scholar
  9. Rapp R.H., Yi Y. (1991); The October 19901x1 Degree Mean Anomaly File including an Analysis of Gravity Information from China; Ohio State University, Department of Geodetic Science and Surveying, Internal Report, Columbus, OhioGoogle Scholar
  10. Rapp R.H., Wang Y.M., Pavlis N.K. (1991); The Ohio State 1991 Geopotential and Sea Surface Topography Harmonic Coefficient Models; Ohio State University, Department of Geodetic Science and Surveying, Report No. 410, Columbus, OhioGoogle Scholar
  11. Schwintzer P., Reigber Ch., Biancale R., Balmino G., and others (1997); Long-WavelengthGlobal Gravity Field Models: GRIM4–S4, GRIM4–C4; Journal of Geodesy, in printGoogle Scholar
  12. Wieser M., (1987); Das globale digitale Höhenmodell TUG87; Interner Bericht, Technische Universität GrazGoogle Scholar

Copyright information

© Springer-Verlag Berlin Heidelberg 1997

Authors and Affiliations

  • Th. Gruber
    • 1
  • M. Anzenhofer
    • 1
  • M. Rentsch
    • 1
  • P. Schwintzer
    • 1
  1. 1.Division 1 D-PAFGeoForschungsZentrum Potsdam (GFZ)OberpfaffenhofenGermany

Personalised recommendations