A high-resolution gravimetric geoid model for Kingdom of Saudi Arabia

Abstract

A high-resolution gravimetric geoid model for the Kingdom of Saudi Arabia area was determined. A data set of 459,848 land gravity, 80,632 shipborne marine gravity data, DTU17 altimetry gravity model, and XGM2019e global geopotential model. The computation strategy followed for modelling of the gravimetric geoid is based on the Remove-Compute-Restore with Residual Terrain Model reduction and the 1D- Fast Fourier Transform approach technique. The geoid heights have been determined by using the Stokes integral with Wong–Gore modification. The accuracy of the resulting geoid models was evaluated by comparing them with 5385 GPS/levelling points. The geoid accuracy over all the kingdom is better than 11 cm in STD sense and the comparison in sub-areas obtained accuracy range from 2.8 to 11.9 cm according to the density of gravity observations.

Keywords:

• Gravity
• Geoid
• Stokes FFT
• GPS/levelling
• Saudi Arabia

Acknowledgement

The authors extend their appreciation to the Deanship of Scientific Research at King Saud University for funding this work through research group No (RG-1440-003). Great thanks are extending to the reviewers for their beneficial review and valuable comments. The authors would like to thank the authors of GRAVSOFT (DTU) for providing their software. The SRTM3arc_v4.1 is available via http://srtm.csi.cgiar.org/SELECTION/inputCoord.asp. The SRTM15arc_plus model is available via https://topex.ucsd.edu/pub/srtm15_plus/. The used XGM2019e is available via http://icgem.gfz-potsdam.de/tom_longtime. The DTU17 gravity is available via https://ftp.space.dtu.dk/pub/. We used the Generic Mapping Tools (GMT) for producing the figures.