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