Validation of European Gravimetric Geoid models in context of realization of EVRS system in Poland

• Main Authors: Dorota Marjańska, Tomasz Olszak, Dominik Piętka
• Format: Article
• Language: English
• Published: Polish Academy of Sciences 2019-12-01
• Series: Geodesy and Cartography
• Subjects: quasi-geoid model; height frame; height anomaly; gnss/levelling
• Online Access: http://journals.pan.pl/dlibra/publication/128461/edition/112064/content

In this study, several variants create and choose of a local quasi-geoid modelin Poland have been considered. All propositions have a source in European GravimetricGeoid models – EGG2008 and EGG2015, which are purely gravimetric models of refer-ence surface. In the course of this work, each model has been analyzed in various ways:without any corrections, by parallel shifting of residuals, by the 7-parameter conformaltransformation and by fitting residuals by 4- and 5-parameter trigonometric polynomials.Eventual corrections were based on points of national GNSS/levelling networks (EUVN,EUVN_DA, POLREF, EUREF and ASG-EUPOS eccentric points). As a final result of thisstudy, a comparison of the accuracy of selected models has been carried out by RMSEstatistics and maps showing spatial distribution of residuals and histograms. Validation hasshown that the maximum achievable accuracy of the EGG models is approximately 2 cmfor the ETRF2000 reference system and approximately 8 cm for ETRF89. In turn, fittingwith the use of different mathematical methods results in an improvement of the standarddeviation of residues to the level of 1.3–1.4 cm. The conclusions include an evaluation ofconsiderations for and against the use of models based only on EGG realizations and, onthe other hand, fitted to the points of Polish vertical network. Its usefulness is strictly con-nected with needs of the definition of up to date quasi-geoid model for the new realizationof heights system in Poland, based on EVRF2007 frame.