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Regional Models


  Authors: O. Kucher, I. Stophai, O. Renkevich     Created: 2005    Resp: M. Ovdii  
      Status: ON DEMAND    
The GM2005 quasi-geoid model for the territory of the Republic of Moldova was computed by the Ukrainian Research Institute of Geodesy and Cartography. The area covered by the models is 45°N - 48.5°N and 26.5°E - 30.5°E with a grid spacing of 1' x 1.5'. It is referred to the GRS80 ellipsoid in the ETRS89 frame. GM2005 was based on the European gravimetric quasi-geoid model EGG97, that was converted into the Baltic normal height system (1977) using a 7-parameter Helmert transformation. A remove-restore procedure was implemented exploiting the global model GGM EIGEN-CG01C up to order and degree 360. Its contribution was first removed from 803 GPS/levelling derived height anomalies and from 2014 grid points of the transformed EGG97 height anomalies. Then, the obtained residuals were interpolated to create a grid by least square collocation. Finally, the height anomalies of the global model were restored. To assess the accuracy of the resulting GM2005 quasi-geoid model, a comparison with independent GNSS/levelling points was performed, showing differences with the standard deviation of about 5 cm.

O. Kucher, U. Stophai, O. Renkevich (2005). Construction of the quasi geoid model on the territory of Republic of Moldova. Internal Report of Ukrainian Research Institute of Geodesy and Cartography, Kiev (in Ukrainian).