On accuracy of current geopotential models estimated through comparison of quasi-geoid models and GPS/levelling data

• Autorzy: Novak P. , Kostelecky J. , Klokocnik J.
• Konferencja: Geodetic and Geodynamic Programmes of the CEI (Central European Initiative) / Proceedings of the EGU G6 Symposium (02-07. 04. 2006 ; Vienna, Austria)
• Języki publikacji: EN

Abstrakty

EN

Gravity-dedicated satellite missions CHAMP and GRACE provide accurate data that can be inverted into geopotential coefficients forming global geopotential models (GGM). Through an estimation process, mean square errors of these coefficients can be elvaluated. In most cases, even the entire variance-covariance matrices are computed. However, these errors are only formaI and do not represent weIl the actual accuracy of estimated coefficients, thus also of various gravity field parameters synthesized from these coefficients. For this reason validation procedures for the new GGMs are being sought since the classical validation methocts reached their limits. This article discusses the validation procedure of the GGM through its comparison with idependent data estimated at selected GPS/leveIling stations over the area of Central Europe. Due to a different spectral content of height anomalies synthesized from the GGM and of those derived from combination of ellipsoidal and normal heights at selected points of the European Vertical Reference Network, the GGM-based low-frequency height anomaly is completed for a missing higth-frequency component based on high resolution and high accuracy ground gravity and elevation data. The methodology is also applied on a set of GPS/leveIling stations in the Czech Republic. In accordance with previous validation tests of GGMs based on data of crossover altimetry, obtained results indicate that the current GGMs estimated from single/dual-sateIlite data seem to have significant problems namely with low-order and degree coefficients.

Słowa kluczowe

EN

geopotential; ggm; global geopotential models; niwelacja; GPS

PL

geopotencjał; GGM; levelling; GPS

• Wydawca: Wydział Geodezji i Kartografii Politechniki Warszawskiej
• Czasopismo: Reports on Geodesy
• Rocznik: 2006
• Tom: z. 1/76
• Strony: 245--251
• Opis fizyczny: Bibliogr. 1 poz., rys., tab., wykr.

Twórcy

autor

Novak P.

autor

Kostelecky J.

autor

Klokocnik J.

• CEDR, Research Institute of Geodesy, Topography and Cartography, 250 66 Zdiby 98, Czech Republic University of Westen Bohemia, Department of Mathematics, Univetrzitni 8, 306 14 Pilsen, Czech Republic

Bibliografia

• 1. Klokočník J, Kostelecký J, Wagner CA, Schwintzer P, Förste C, Scharroo R (2005) Evaluation of the accuracy of the EIGEN-1S and 2 CHAMP-derived gravity field models by satellite crossover altimetry. Journal of Geodesy 78: 405-417.
• 2. Kostelecký J, Klokočník J, Wagner CA, Scharroo R, Gruber C, Bezdek A, Doornbos E, Novák P (2006) Degradation in accuracy of CHAMP/GRACE-only earth gravity field models. Presented at 3rd EGU Assembly Vienna, April 2006.
• 3. Kostelecký J (jr.) (2004) Elevation and gravity database GOP30x30. Internal report of the Research Institute of Geodesy, Topography and Cartography, Prague.
• 4. Molodensky MS, Eremeev VF, Yurkina MI (1960) Methods for study of the external gravitational field and figure of the Earth. Translated from Russian by the Israel Program for Scientific Translations, Office of Technical Services, Department of Commerce, Washington, D.C., 1962.
• 5. Novák P (2000) Evaluation of gravity data for the Stokes-Helmert solution to the geodetic boundary-value problem. Doctor of Philosophy dissertation, Department of Geodesy and Geomatics Engineering, University of New Brunswick, Fredericton.
• 6. Vaníček P, Kleusberg A (1987) The Canadian geoid - Stokesian approach. Manuscripta Geodaetica 12: 86-98.