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Regional Models

Faroe Islands (FOGEOID2010)

  Author: R. Forsberg     Created: 2010    Resp: Stein Fossá  
      Status: PRIVATE    
This is a gravimetric geoid for Faroe Islands, covering the area 61-63°N and 9-5°W, with a spatial resolution of 0.005° x 0.01° corresponding to about 500 m. The reference ellipsoid is WGS84. The used gravity database consists of land gravity observations from Geodetic Institute, more recent gravity data collected in 2009, and marine gravity measurements from Danish and international sources. The data coverage in and around the Faroe Islands was quite good. The gravimetric geoid was computed in the framework of a remove-restore technique with the GRAVSOFT software. The adopted global gravity model was EGM2008 up to degree and order 720. The residual terrain correction was based on a 50 m resolution terrain model. The transformation from reduced gravity data to reduced geoid heights was performed by spherical Fast Fourier Transform (FFT), where the Stokes integral is modified according to the Wong-Gore method for spherical harmonic degrees over a band in the range 80-90. This ensures that the long wavelengths were mainly determined from satellite information (GRACE), reducing possible long-wave errors in the marine gravity data. Based on the available observations and their spatial coverage, the error of this gravimetric geoid model is estimated to be better than 5 cm, and locally it could be of 2-3 cm.

R. Forsberg (2010). Ny gravimetrisk geoide for Færøerne. Report, DTU-Space (in Danish).

Faroe Islands