ANDALUSGeoid2002: The new gravimetric geoid model of Andalusia (southern Spain)

Abstract

In the 1991 the first determination of a gravimetric geoid in a test area in central Spain was computed by using least square collocation. In 1995 a gravimetric geoid in the Iberian Peninsula, Ibergeo95, was calculated by FFT. Nowadays an improved geoid of Andalusia, ANDALUSGeoid2002, has been computed by fast collocation procedure and remove-restore technique in the GRS80 Reference System. The computations have been done from 16562 free-air gravity anomaly data set, obtained from IGN (Instituto Geografico Nacional) and BGI (International Gravity Bureau), the Earth Gravity Model EGM96 and detailed (100 m x 100 m), coarse (5 km x 5 km) and reference (20 km x 20 km) digital terrain models. Relative carrier-phase GPS measurements at 69 benchmarks of the Spanish Levelling Network in Andalusia have been done. The standard deviations of differences between +/-11 cm, +/-39 cm and +/-38 cm in western, eastern and whole Andalusia, respectively. The ANDALUSGeoid2002 shows an improvement of Ibergeo95 in this territory.