Evaluation of Quasi-Geoid Model Based on Astrogeodetic Measurements: Case of Latvia

Journal of Applied Geodesy 2021
Katerīna Runde, Reiner Jäger, Ansis Zariņš, Jānis Balodis, Inese Vārna, Gunārs Silabriedis

Since the development of GNSS techniques, the determination of a precise quasi-geoid model has become even more actual. In terms of this project the staff of the Institute of Geodesy and Geoinformatics (GGI) has developed a new quasi-geoid model based on DFHRS (Digital Finite-element Height Reference Surface) approach additionally using astrogeodetic measurements – vertical deflections (VD), which can be observed by a Digital zenith camera. This paper evaluates a quasi-geoid model results based on vertical deflections, as a study area using the territory of Latvia: the standard deviation of the solution is equal to 0.006 m with observation residuals after the adjustment of minimum and maximum differences −0.012 and 0.012 accordingly. The standard deviation of quasi-geoid heights and h-H values from LGIA database is equal to 0.012 m with minimum and maximum differences −0.026 and 0.025 accordingly. The post-processed terrestrial VD observations have been compared to VD derivatives from EGM2008 and GGMplus geopotential models. The developed quasi-geoid has been compared to the national quasi-geoid model LV’14 and to the Scandinavian NKG2015.

Keywords
Digital zenith camera, EGM2008, GGMplus,quasi-geoid, vertical deflection
DOI
10.1515/jag-2021-0030
Hyperlink
https://doi.org/10.1515/jag-2021-0030

Morozova, K., Jäger, R., Zariņš, A., Balodis, J., Vārna, I., Silabriedis, G. Evaluation of Quasi-Geoid Model Based on Astrogeodetic Measurements: Case of Latvia. Journal of Applied Geodesy, 2021, Vol. 15, No. 4, pp. 319-327. ISSN 1862-9016. e-ISSN 1862-9024. Available from: doi:10.1515/jag-2021-0030

Publication language
English (en)