Potentially Misleading GPS Leveling-Based Assessment of Gravimetric Geoid or Quasigeoid Models due to Vertical Land Motion and Different GPS Processing Software

Abstract

© 2019 American Society of Civil Engineers. Gravimetric geoid or quasigeoid models are often evaluated using Global Positioning System (GPS) and leveling, but the veracity of these control data is not always considered. Using a precisely surveyed 40-km-long traverse of 62 points in Perth, Western Australia, we exemplify that vertical land motion and the choice of GPS processing software may lead to spurious conclusions as to which is the best model, particularly with regard to the assessment in the presence of tilts among these data sets. We recommend that the effect of vertical land motion (if present) be factored into such evaluations, GPS data be processed using the same software and in the same reference frame, and tilts among the data sets be considered during the evaluations.