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Regional Models

Uruguay (URUGEOIDE2000)


  Author: W.H. Subiza Piña, et al.     Created: 2000    Resp: W.H. Subiza Piña  
      Status: PUBLIC   
Description:
This is a geoid model for Uruguay computed by Servicio Geográfico Militar. It is referred to the WGS84 geodetic system and covers the area from -30° to -35° latitude and from 301.5° to 307° longitude. The input gravity data were 5873 ground observations, 9987 marine free-air anomalies from the GMGA9706 model, the EGM96 geopotential model. The topographic data were compiled from the 2 km x 2 km SGM digital terrain model, the 2.5' x 2.5' USP model and from the GTOPO30 global topographic model. The remove-restore technique was applied by combining the mentioned datasets. The external masses to the geoid was considered with the second Helmert condensation method, taking in account the indirect effect. The gravimetric contribution was calculated using residual free-air anomalies in the spherical Stokes formula, evaluated with 1D-FFT. The resulting geoid was adapted by a bias and a tilt to the national vertical system, Montevideo 1948, by fitting GPS/levelling observations, with a resulting accuracy of 13 cm.

References:
W.H. Subiza Piña, C. Gemael, N. Cogo de Sá (2001). URUGEOIDE 2000 project: a gravimetric geoid for Uruguay, IGeS Bulletin, 11, pp. 11-20.
W.H. Subiza Piña, H. Rovera Di Landro, L. Turban (2002). The Vertical Datum and Local Geoidal Models in Uruguay. In: H. Drewes, A.H. Dodson, L.P. Souto Fortes, L. Sanchez, P. Sandoval (eds.), Vertical Reference Systems, IAG Symposia Series, vol. 124, pp. 169-175, Springer Verlag.

Uruguay