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Regional Models

Auvergne - France (AuvGeoid2019-UNB-LS)


  Authors: I. Foroughi, et al.     Created: 2019    Resp: I. Foroughi  
      Status: PUBLIC    
Description:
The AuvGeoid2019-UNB-LS model is a gravimetric geoid computed for the Auvergne test area by using the UNB Stokes-Helmert's technique (most probable solution). Both scattered and grid gravity data were used at the Earth's surface. The gravity data were transferred to a harmonic space using the Helmert second condensation method (including the effect of lateral topographical density variation). The Poisson integral equation was used for the downward continuation of the gravity data to the geoid using the Least-Squares (LS) technique and this is the main difference with respect to the AuvGeoid2017-UNB model. The comparison of the obtained geoidal heights with those derived from 75 GNSS/levelling control points (regularly spaced throughout the region) shows a misfit of 3.3 cm in standard deviation(external accuracy). The mean internal accuracy (of 6 mm) is estimated from the input data accuracy by propagating the error through the derivation of geoidal heights. Considering the error of the GNSS/levelling control points, these internal estimates agree well with the external estimates, giving more confidence that the mean internal accuracy of 6 mm is fairly reliable.

Reference:
I. Foroughi, P. Vaníček, R.W. Kingdon, M. Goli, M. Sheng, Y. Afrasteh, P. Novák, & M.C. Santos (2019). Sub-centimetre geoid. Journal of Geodesy, 93, pp. 849-868. DOI: 10.1007/s00190-018-1208-1

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