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Regional Models

Corsica (GGF97)


  Authors: A. Harmel, J.M. Nocquet     Created: 1997    Resp: F. L'Ecu  
      Status: PUBLIC    
Description:
GGF97 is a geoid model for France and Corsica. It is computed by interpolating 1100 GPS/levelling points of the RBF (Reseau de Base Francais) and it represents the height of the IGN69 (for continental France) and IGN78 (for Corsica) reference surface above the GRS80 ellipsoid. The interpolated regular grid has a spatial resolution of 0.1° x 0.1° (about 10 km) and the used interpolation method is a least squares adjustment with bilinear functions and with the constraint of equal slope at each node. Moreover, in order to avoid edge effects, the OSU91 global gravity model is used outside France. The GGF97 accuracy is estimated from 10 to 15 cm in plain areas and from 30 to 50 cm on the reliefs.

References:
IGN (1998). Geoide Geometrique Francais - GGF97. Notes Techniques. Institut Geographique National, Service de Geodesie et Nivellement.


France