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IGFS 2014 pp 123-129 | Cite as

A New Gravimetric Geoid Model for the Area of Sudan Using the Least Squares Collocation and a GOCE-Based GGM

  • Walyeldeen GodahEmail author
  • Jan Krynski
Part of the International Association of Geodesy Symposia book series (IAG SYMPOSIA, volume 144)

Abstract

The determination of an accurate geoid model remains an important challenge for geodetic research in Sudan. The presented contribution concerns the determination of a new gravimetric geoid model (SUD-GM2014) for the area of Sudan using recent released GOCE-based Global Geopotential Models (GGMs), available terrestrial mean free-air gravity anomalies and the high-resolution SRTM30_PLUS global digital elevation model. The computations of the SUD-GM2014 were performed using remove-compute-restore (RCR) procedure and the least squares collocation method. The residual terrain modelling (RTM) reduction method was applied to estimate the topography effect on the geoid. The resulting gravimetric geoid model has been evaluated using geoid heights at 19 GNSS/levelling points distributed over the country. The evaluation results and the expected quality of the SUD-GM2014 geoid model were discussed considering the quality of GNSS/levelling data in Sudan. The SUD-GM2014 or the geoid model computed from GOCE-based GGMs only has been recommended as reference for GNSS heighting in Sudan.

Keywords

Geoid Global geopotential model GNSS/levelling GOCE Least squares collocation 

Notes

Acknowledgements

The authors would like to thank Prof. Derek Fairhead from GETECH, Leeds University for providing terrestrial gravity data for the area of Sudan. This study is a part of the first author PhD research. The University of Khartoum, Sudan, as well as the Institute of Geodesy and Cartography (IGiK), Warsaw, Poland, are kindly acknowledged for their partial financial support. The discussions concerning the research and the preparation of the manuscript with the team of the Centre of Geodesy and Geodynamics of the IGiK are kindly acknowledged.

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Copyright information

© Springer International Publishing Switzerland 2015

Authors and Affiliations

  1. 1.Centre of Geodesy and Geodynamics, Institute of Geodesy and CartographyWarsawPoland

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