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Regional Models

France (RAF09)

  Author: IGN     Created: 2009    Resp: F. L'Ecu  
      Status: PUBLIC    
RAF09 is a hybrid geoid model for France, covering the area 42° < lat < 51.5°, -5.5° < lon < 8.5° with a grid spacing of 1.5' in latitude and 2' in longitude. It is an update of the previous RAF98 model. In particular it is an adaptation of the QGF98 model to 941 GPS/levelling points, with improvements coming from the QGC02 model in Provence and a quasi-geoid model for Auvergne computed for an European test. Note also that the ellipsoidal heights of the GPS/levelling network were re-observed by IGN between 2000 and 2008. The RAF09 model represents the height of the IGN69 reference surface above the GRS80 ellipsoid. It has been assessed by using 1160 independent GPS/levelling points, showing that its use for a levelling by GPS allows to obtain elevations with an accuracy between one and two centimeters.

F. Duquenne (2010). Evolution des references verticales. Journee Geodesie, 14 Octobre 2010.
IGN (2010). Descriptifs quasi-geoides et grilles de conversion altimetrique sur la France metropolitaine. Laboratoire de Recherche en Geodesie, Service de Geodesie et Nivellement.