Improvement of Local Geoid Model in Thailand Using Residual Terrain Model and Terrestrial Gravities

Authors

  • Sattawat Mukdaharn Department of Civil Engineering, Faculty of Engineering, Chiang Mai University, Chiang Mai, Thailand; Mapping Technology Division, Department of Lands, Bangkok, Thailand
  • Puttipol Dumrongchai Department of Civil Engineering, Faculty of Engineering, Chiang Mai University, Chiang Mai, Thailand

Keywords:

Geoid, Residual Terrain Model (RTM), GNSS, Omission Errors

Abstract

This research aimed to improve a local geoid model using EGM2008 along with the residual terrain model (RTM) and terrestrial gravities in Thailand for converting GNSS-derived ellipsoid heights into orthometric heights. The determination of the geoid models, based on Molodensky’s theory, covered flatted terrain, moderate terrain and mountainous areas across the country. The geoid models were evaluated using 352 GNSS heights co-located with orthometric heights, with reference to the Kolak national vertical datum of 1915. The results showed that using the combination of terrestrial gravity data and RTM in the computation significantly improved the accuracy of the geoid models. The standard deviation values decreased to the centimeter levels, indicating the reduction of the omission errors contaminated in geoid modeling, which were due to the lack of gravimetric and coherent quantities in the areas.

References

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Published

2020-12-31

How to Cite

Mukdaharn, S., & Dumrongchai, P. (2020). Improvement of Local Geoid Model in Thailand Using Residual Terrain Model and Terrestrial Gravities. Science and Engineering Connect, 43(4), 505–516. retrieved from https://ph04.tci-thaijo.org/index.php/SEC/article/view/10689

Issue

Vol. 43 No. 4 (2020): October - December

Section

Research Article

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