Assessment of Gravity Field and Steady State Ocean Circulation Explorer (GOCE) geoid model using GPS levelling over Sabah and Sarawak

• Main Authors: Din, A.H.M (Author), Omar, K.M (Author), Othman, A.H (Author), Pa'Suya, M.F (Author), Som, Z.A.M (Author), Yahaya, N.A.Z (Author)
• Format: Article
• Language: English
• Published: Institute of Physics Publishing 2016
• Subjects: assessment method; East Malaysia; geodesy; Geodesy; Geodetic satellites; geoid; Geoid heights; Geoid models; Global geopotential models; Global positioning system; GOCE; GOCE satellites; GPS; Gravity data; gravity field; Gravity field; Gravity field and steady state ocean circulation explorers; height determination; leveling; Malaysia; numerical model; Oceanography; Remote sensing; Sabah; Sarawak; satellite mission; software
• Online Access: View Fulltext in Publisher; View in Scopus

 The GOCE satellite mission has significantly contributed to various applications such as solid earth physics, oceanography and geodesy. Some substantial applications of geodesy are to improve the gravity field knowledge and the precise geoid modelling towards realising global height unification. This paper aims to evaluate GOCE geoid model based on the recent GOCE Global Geopotential Model (GGM), as well as EGM2008, using GPS levelling data over East Malaysia, i.e. Sabah and Sarawak. The satellite GGMs selected in this study are the GOCE GGM models which include GOCE04S, TIM-R5 and SPW-R4, and the EGM2008 model. To assess these models, the geoid heights from these GGMs are compared to the local geometric geoid height. The GGM geoid heights was derived using EGMLAB1 software and the geometric geoid height was computed by available GPS levelling information obtained from the Department Survey and Mapping Malaysia. Generally, the GOCE models performed better than EGM2008 over East Malaysia and the best fit GOCE model for this region is the TIM-R5 model. The TIM-R5 GOCE model demonstrated the lowest R.M.S. of ± 16.5 cm over Sarawak, comparatively. For further improvement, this model should be combined with the local gravity data for optimum geoid modelling over East Malaysia.