Computing height anomalies using spherical harmonic coefficients at certain degrees and orders in long-wavelength components

Abstract

Height anomaly / geoid undulation) is a basic quantity in geodesy. It can be directly measured from GPS and leveling or computed from gravitational models. This paper introduces program GeoH to compute height anomalies using spherical harmonic coefficients at certain degrees and orders in longwavelength components. By reasonably comparing with official values of EGM96, the reliability of results from GeoH is proved for the long-wavelength components, and then can be applied in the “remove-restore” technique for determining Vietnamese quasi-geoid in near future.