The gravimetric geoid model xGGM23 was computed at the University of New Brunswick, Canada, with the aim to update the national geoid for Mexico, as well as to contribute to the construction of the regional geoid for North and Central America. Terrestrial gravimetry collected up to year 2020 was processed in spectral combination with the satellite-derived geopotential model GOCO06s (up to degree and order 230) using the UNB’s Stokes-Helmert technique. The geoid model is purely gravimetric, corresponds to the regional standard reference gravity potential for North America (Wo=6263656.0 m2/s2), tide-free gravity concept, and covers latitudes from 10° N to 40° N and longitudes from 125° W to 80° W, with a grid resolution of 2.5 arc minutes. This resolution is coherent with the densification of terrestrial gravity data collected inside Mexico. The accuracy of geoidal height is estimated as 10 cm inside Mexico and 5 cm in the southern US.
The geoid model is provided in ISG format 2.0 (ISG Format Specifications), while the file in its original data format is available at the model ISG webpage.
The International Service for the Geoid (ISG) was founded in 1992 (as International Geoid Service - IGeS) and it is now an official service of the International Association of Geodesy (IAG), under the umbrella of the International Gravity Field Service (IGFS). The main activities of ISG consist in collecting, analysing and redistributing local and regional geoid models, as well as organizing international schools on the geoid determination.