Evaluation of quasi-geoid model based on astrogeodetic measurements: case of Latvia

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