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Regional Models

Russia (RGG-2003)

  Authors: P. Medvedev, V. Nepoklonov   Created: 2003    Resp: V. Nepoklonov  
      Status: PUBLIC    
The model "Russian Gravimetric Geoid (version 2003)", hereinafter referred to as RGG-2003, is a grid of quasigeoid heights for the territory of Russia. The covered area extends from 80° to 40° in latitudes and from 26° to 190° in longitudes, with a grid step of 5' along both meridians and parallels. The grid nodes are given in the national geocentric coordinate system of the Russian Federation, "Parameters of the Earth, 1990" (PZ-90). The RGG-2003 quasigeoid heights are referred to the PZ-90 Earth ellipsoid with the following parameters: a = 6,378.136 km, f = 1/298.25784.
The input data used for computing the quasigeoid heights on grid nodes were:
- the global model of Earth gravitational field EGM96 up to degree and order 360;
- mean gravity anomalies on the trapezoid of 5'×5', obtained using digitized gravimetric maps with scale 1:1,000,000 of the territory of the former Soviet Union;
- mean relief heights on the trapezoid of 5'×5', obtained using digitized topographic maps with scale 1:200,000 of the territory of the former Soviet Union.
The RGG-2003 model was computed by using a remove-restore approach with respect to the reference model EGM96. After removing this global model from the input gravity anomalies, the Molodenskii corrections, in the first approximation, calculated using the analytical continuation method, were applied. Conversion from gravity anomalies to quasigeoid heights were performed by Stokes integral formulas, which was implemented through a convolution method in the frequency domain and the Fast Fourier Transform algorithm on the plane.

P. Medvedev, V. Nepoklonov (2003). RGQG-2003: The new geoid and gravity field model for territory of Russia and sea areas around Russia. Presented at IUGG 2003, June 30 – July 11, 2003, Sapporo, Japan. Abstracts Week B, P. 169.