Comparison of different global DTMs and GGMs over Sri Lanka
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Weeramuni Javana Praboni De Silva
and
Herath Mudiyanselage Indika Prasanna
Abstract
Digital Elevation Models (DEMs) are real-world geographical databases that are important in studying many Earth related topics. Because the vertical accuracy of global DEMs differs across regions due to various reasons, acquiring reliable heights for a region using global height models is crucial. The objective of this study is to compare and assess the most reliable global height model for Sri Lanka. The official height system in Sri Lanka is the Mean Sea Level (MSL) based orthometric height system. In this study, the quality of ASTER, SRTM, NASADEM, MERIT, and DEMs compiled from digitized contour data of Sri Lanka was evaluated using the known heights of the Fundamental Benchmarks (FBMs) of Sri Lanka. In addition, recently published high-resolution Global Geopotential Models (GGMs) were used for the accuracy assessments of gravity related quantities computed using DEMs. The SGG-UGM-2 GGM, which showed the minimum STD and RMSE of geoid undulation difference was found as the best fit GGM over Sri Lanka. It was found that the NASADEM at its highest resolution, which gave the lowest RMSE of 2.954 m was the best global DEM for Sri Lanka.
Acknowledgments
The Authors express their sincere gratitude to Prof. Dai Yamazaki of the University of Tokyo who has given permission to download the MERIT DEM data.
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Author contributions: All the authors have accepted responsibility for the entire content of this submitted manuscript and approved submission.
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Research funding: None declared.
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Conflict of interest statement: The authors declare no conflicts of interest regarding this article.
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Articles in the same Issue
- Frontmatter
- Research Articles
- 3D concept creation of permanent geodetic monitoring installations and the a priori assessment of systematic effects using Virtual Reality
- Modeling the gravitational effects of ocean tide loading at coastal stations in the China earthquake gravity network based on GOTL software
- Comparison of different global DTMs and GGMs over Sri Lanka
- Performance tests of geodetic receivers with tilt sensors in obstructed environments using the NRTK GNSS technique
- Fitting a triaxial ellipsoid to a set of quasi-selenoidal points
- A real-time algorithm for continuous navigation in intelligent transportation systems using LiDAR-Gyroscope-Odometer integration
- Ionospheric scintillation characteristics from GPS observations over Malaysian region after the 2011 Valentine’s day solar flare
Articles in the same Issue
- Frontmatter
- Research Articles
- 3D concept creation of permanent geodetic monitoring installations and the a priori assessment of systematic effects using Virtual Reality
- Modeling the gravitational effects of ocean tide loading at coastal stations in the China earthquake gravity network based on GOTL software
- Comparison of different global DTMs and GGMs over Sri Lanka
- Performance tests of geodetic receivers with tilt sensors in obstructed environments using the NRTK GNSS technique
- Fitting a triaxial ellipsoid to a set of quasi-selenoidal points
- A real-time algorithm for continuous navigation in intelligent transportation systems using LiDAR-Gyroscope-Odometer integration
- Ionospheric scintillation characteristics from GPS observations over Malaysian region after the 2011 Valentine’s day solar flare
