Analysis of normal height differences determination in Lithuanian national geodetic vertical network

Abstract

Activities on Lithuanian National Geodetic Vertical Network establishment are presented. Method used for precise normal height difference determination is described. Improvements of pre-programmed observation sequence of digital level Wild NA3003 are listed. Analysis of calibration results and correction computation is presented. Algorithm of normal height difference computation is given. Refraction influence on height difference determination in levelling is described. Refraction and celestial bodies influence is analysed. Evaluation of gravity field equipotential surfaces non-paralellity is presented. Accuracy of computed height differences is presented and conclusions are made.