Methodology for optimizing heights in the Amsterdam system based on regional and global geoid/quasi-geoid models

The article presents a methodology for transitioning to the Amsterdam height system based on utilizing global and regional geoid/quasi-geoid models. The study was conducted for the Polish-Ukrainian cross-border sector and expanded to the entire territory of Poland and Ukraine. The input data comprised two regional and five global geoid/quasi-geoid models. The initial data analysis was conducted for all models relative to GNSS/leveling data in the Baltic height system. The secondary analysis was performed relative to the combined PL-quasi-geoid2021 model and the gravimetric EGG2015 model. Based on the analysis results, a methodology for optimizing heights between regional and global geoid/quasi-geoid models was developed, including the following stages: calculation of conditional global and regional geoid/quasi-geoid heights, calculation of approximately predicted height differences between the conditional regional and global geoid/quasi-geoid, implementation of the refinement (correction) of approximate heights at the regional model, optimization of approximate heights at the regional model, and calculation of a regional combined model in the Amsterdam height system. The developed methodology enables the integration of regional and global geoid/quasi-geoid models into the Amsterdam height system with an accuracy of 1–2 cm by optimizing their heights. The advantage of this methodology is that it requires only a minimal amount of GNSS/leveling data to establish connections between different height systems.