CD International Geoid School
for Determination and Use of the Geoid 1994-2010
(with program and exercises)

Matlab functions to read and write geoid/quasi-geoid models in ISG format. The reader is able to read all the versions of the format (v 1.0, v 1.01 and v 2.0), while the writer can write models only according to the newest v 2.0 of the format, since the older ones are deprecated.

The zip package contains the two functions and an example on their usage

Spherical Harmonics Manipulator

Software supported by the Italian Space Agency through the GOCE-Italy project (rif. dr. tec-001-GOCEI-1.0)

• geoid ondulations 
• gravity anomalies 
• components of deflection of the vertical

using ellipsoidal global model coefficients (Nmax= 360) developed in ellipsoidal harmonic functions (derived from global model EGM96)

source code

coefficients

Program to compute terrain effects on gravimetric quantities

(source and example file windows zip)

readme

source code

examples

Python package for geoid file format conversion

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open-source Python package (GPL-3.0) designed for gravity-field analysis and high-accuracy regional gravimetric geoid computation using the remove-compute-restore technique. It provides a complete, automated pipeline including gravity reductions, terrain corrections, and Stokes' kernel integration (with 3 modifications). The software supports automatic downloads of GGMs from ICGEM and various DEMs. It features a clean CLI with a configuration file, comprehensive documentation, and is accompanied by the following publication:

C. Kelly, V.G. Ferreira, D. Yang, S.A. Andam-Akorful, D. Yan, S. Osah, C.M. Hancock, G. Jing, A.T. Kabo-bah (2026). GeoidLab: An automated open-source Python toolbox for gravity-field analysis and vertical datum unification. Earth Science Informatics, vol. 19, 66. DOI: 10.1007/s12145-026-02118-6

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tutorial

OSVGeo is a software package for regional geoid determination. It computes a gravimetric geoid from gravity observations (terrestrial, airborne, scalar or vector, together with the long wavelengths from satellite gravity models) and delivers mean geoid heights on a regular grid. The geoid modelling is based on UNB’s Stokes-Helmert approach.

The software was developed jointly with Dr. Mehdi Goli, in partnership with Sander Geophysics Ltd and with contributions from Dr. Spiros Pagiatakis. Its continued development and expansion is hosted by the Quantum Physical Geodesy Lab at the University of Calgary.

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