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Incorporating Topographic-Isostatic Information into GOCE Gravity Gradient Processing

  • Thomas Grombein
  • Kurt Seitz
  • Bernhard Heck
Chapter
Part of the Advanced Technologies in Earth Sciences book series (ATES)

Abstract

Global high-resolution digital terrain models provide precise information on the Earth’s topography, which can be used to determine the high- and mid-frequency constituents of the gravity field (topographic-isostatic signals). By using a Remove-Compute-Restore concept these signals can be incorporated into many methods of gravity field modelling. Due to the smoothing of observation signals such a procedure benefits from an improved numerical stability in the calculation process. In this paper the Rock-Water-Ice topographic-isostatic gravity field model is presented that we developed in order to generate topographic-isostatic signals which are suitable to smooth gravity gradients observed by the satellite mission GOCE. In contrast to previous approaches, this model is more sophisticated due to a three-layer decomposition of the topography and a modified Airy-Heiskanen isostatic concept. By using measured GOCE gravity gradients, the degree of smoothing is analyzed, showing a significant reduction of the standard deviation (about 30 %) and the range (about 20–40 %). Furthermore, we validate the performance of the generated topographic-isostatic signals by means of a wavelet analysis.

Keywords

Gravity Field Digital Terrain Model Gravity Gradient Spherical Harmonic Coefficient Spherical Harmonic Degree 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

Notes

Acknowledgments

This research was funded by the German Federal Ministry of Education and Research under grant number 03G0726F within the REAL GOCE project of the GEOTECHNOLOGIEN Programme. N.K. Pavlis (NGA) is acknowledged for providing the topographic data base DTM2006.0. Furthermore, the authors would like to thank X. Luo (KIT) sincerely for his great support in performing the wavelet transform and producing the wavelet spectrograms.

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Copyright information

© Springer-Verlag Berlin Heidelberg 2014

Authors and Affiliations

  1. 1.Geodetic InstituteKarlsruhe Institute of Technology (KIT)KarlsruheGermany

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