The Accuracy Verification of Recent Global Geopotential Model based on GNSS/Levelling Data on Ground Control Points in Johor

Abstract

The external gravitational field of the Earth is mathematically represented using spherical harmonic (SH) coefficients in the global geopotential model. Hence, the appropriate global geopotential model for a region needs to determine a reference surface that refers to geoid heights specific for coastal erosion, flood and many more. The aim of this study is to estimate the best global geopotential model model in Johor region which is selected based on satellite only and combined model for the years 2018 until 2022. Next, the global geopotential models are verified with Global Navigation Satellite System (GNSS) levelling data based on root mean square deviation (RMSE) value in Johor region near coastal area. The findings found that EIGEN-GRGS.RL04. MEAN_FIELD has the lowest RMSE values that represent the highest accuracy with 0.1911m than the other models in their respective categories and represent the best adjustment model. In conclusion, the global geopotential model (GGM) is the most suitable used as a reference for future studies in Johor region from the satellite-only model of EIGEN-GRGS.RL04. MEAN_FIELD with the degree and order 300 compared to other models.