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Regional Models


  Author: J.G. Olliver     Created: 2007    Resp: J.G. Olliver 
      Status: PUBLIC   
The geoid of Tanzania, bounded by lat: 14S-1N and lon: 27E-42E, was determined at a resolution grid of 5 minutes of arc. The GRS80 reference system was used. The data used included the EIGEN-GRACE02S geopotential model up to degree and order 120, a terrestrial gravity data anomaly set, marine (ship track) gravity and satellite radar altimetry data. A digital terrain model derived from SRTM was also used to compute topographical effects. The spherical one-dimensional FFT method was used to compute the geoid heights residual to the geopotential model. Internal error propagation was used to get a pessimistic accuracy estimate of 30 cm.

J.G. Olliver (2007). The Gravimetric geoid of Tanzania. Survey Review, 39(305), pp. 212-225.