Assessment and fitting of high/ultra resolution global geopotential models using GNSS/levelling over Egypt
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Abdelaty Mohammed Zayed
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Ahmed Saber
Abstract
This study conducts an evaluation of the performance of seven ultra-high-degree Global Geopotential Models (GGMs) across Egypt, utilizing GNSS/leveling data as a basis for assessment. The models under investigation include SGG-UGM-2, XGM2019e_2159, SGG-UGM-1, GECO, EIGEN-6C4, EGM2008, and GGMplus. The evaluation procedure comprises three principal steps: an absolute assessment, the implementation of Residual Terrain Modelling (RTM), and the fitting of GGMs to GNSS/leveling data. Among the models assessed, GECO exhibited the highest performance in the absolute assessment, achieving a standard deviation (STD) of 0.310 m, while SGG-UGM-1 recorded the largest STD at 0.353 m. Given Egypt’s predominantly flat topography, the application of RTM yielded only modest benefits. Nonetheless, all models demonstrated significant enhancements in accuracy through the fitting process, with EIGEN-6C4 emerging as the most successful model, attaining an STD of 0.116 m in external assessment. The accuracy improvements following the fitting procedure ranged from 49 % to 63 % across all models assessed.
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Research ethics: Not applicable.
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Informed consent: Not applicable.
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Author contributions (for double- anonymized journals: please use initials): All authors have accepted responsibility for the entire content of this manuscript and approved its submission.
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Use of Large Language Models, AI and Machine Learning Tools: None declared.
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Conflict of interest: The authors state no conflict of interest.
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Research funding: None declared.
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Data availability: Not applicable.
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© 2024 Walter de Gruyter GmbH, Berlin/Boston
Artikel in diesem Heft
- Frontmatter
- Original Research Articles
- Locally robust Msplit estimation
- Extending geodetic networks for geo-monitoring by supervised point cloud matching
- Evaluation and homogenization of a marine gravity database from shipborne and satellite altimetry-derived gravity data over the coastal region of Nigeria
- Modelling geoid height errors for local areas based on data of global models
- Unmanned aerial vehicle-based aerial survey of mines in Shanxi Province based on image data
- Ionospheric TEC and its irregularities over Egypt: a comprehensive study of spatial and temporal variations using GOCE satellite data
- Monitoring of volcanic precursors using satellite data: the case of Taftan volcano in Iran
- Modeling of temperature deformations on the Dnister HPP dam (Ukraine)
- Impact of temporal resolution in global ionospheric models on satellite positioning during low and high solar activity years of solar cycle 24
- Comparative performance of PPP software packages in atmospheric delay estimation using GNSS data
- Assessment and fitting of high/ultra resolution global geopotential models using GNSS/levelling over Egypt
- An efficient ‘P1’ algorithm for dual mixed-integer least-squares problems with scalar real-valued parameters
- Spatio-temporal trajectory alignment for trajectory evaluation
- Monitoring of networked RTK reference stations for coordinate reference system realization and maintenance – case study of the Czech Republic
- Crustal deformation in East of Cairo, Egypt, induced by rapid urbanization, as seen from remote sensing and GNSS data
Artikel in diesem Heft
- Frontmatter
- Original Research Articles
- Locally robust Msplit estimation
- Extending geodetic networks for geo-monitoring by supervised point cloud matching
- Evaluation and homogenization of a marine gravity database from shipborne and satellite altimetry-derived gravity data over the coastal region of Nigeria
- Modelling geoid height errors for local areas based on data of global models
- Unmanned aerial vehicle-based aerial survey of mines in Shanxi Province based on image data
- Ionospheric TEC and its irregularities over Egypt: a comprehensive study of spatial and temporal variations using GOCE satellite data
- Monitoring of volcanic precursors using satellite data: the case of Taftan volcano in Iran
- Modeling of temperature deformations on the Dnister HPP dam (Ukraine)
- Impact of temporal resolution in global ionospheric models on satellite positioning during low and high solar activity years of solar cycle 24
- Comparative performance of PPP software packages in atmospheric delay estimation using GNSS data
- Assessment and fitting of high/ultra resolution global geopotential models using GNSS/levelling over Egypt
- An efficient ‘P1’ algorithm for dual mixed-integer least-squares problems with scalar real-valued parameters
- Spatio-temporal trajectory alignment for trajectory evaluation
- Monitoring of networked RTK reference stations for coordinate reference system realization and maintenance – case study of the Czech Republic
- Crustal deformation in East of Cairo, Egypt, induced by rapid urbanization, as seen from remote sensing and GNSS data
