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Regional Models

France (QGF16)

  Author: F. L-Ecu     Created: 2016    Resp: F. L'Ecu  
      Status: PUBLIC    
QGF16 is a gravimetric quasi-geoid model covering mainland France. More specifically, it covers the area 42° < lat < 51.5°, -5.5° < lon < 8.5°, with a grid spacing of 1.5' in latitude and 2' in longitude. The reference ellipsoid is GRS80. The model was computed by the remove-restore technique, using 875,661 values of terrestrial and marine gravity anomalies. The reference global gravity model was EGM2008 up to degree and order 720. The used digital terrain model was BDTopo of the IGN (30 m resolution) for the terrestrial part of mainland France, SRTM for terrestrial parties abroad, and Sandwell for the marine part. The quasi-geoid QGF16 was calculated by the Stokes method using an integration radius of 2°. The model was assessed by comparing it with the GPS/levelling points of the ERNIT program, showing residuals with a standard deviation of 6.7 cm after detrending.

F. L'Ecu (2017). Calcul du quasi-géoïde QGF16 et de la grille de conversion altimétrique RAF16 état d’avancement et perspectives. Revue XYZ, 150, pp. 49-51