A comparative study of the recent geopotential models for synthesizing different gravity functional at the geographical region of Iran■

Document Type : Research Article


1 Department of Surveying and Geomatics Engineering, Center of Excellence of Surveying and Disaster Management, University of Tehran

2 National Cartographic Center of Iran


Recent progress in the field of satellite, airborne, and surface gravimetry has resulted in geopotential models with high resolution. Since the geopotential models are computed based on dense and highly accurate gravity data, they are valuable sources of information for presentation of long and medium wavelength spectrum of the gravity field in the computational algorithm of modern gravity field modeling techniques. Considering the variety of the geopotential models which are currently available, it is necessary to verify their accuracy in synthesizing the gravity functional so that one can select the best geopotential model for a region of interest. In this study 4 geopotential models, namely:  EGM96, PGM2000A, Eigen-cgo1c, Eigen-Grace2s, are compared for their accuracy in synthesizing gravity functional of the types: (1) astronomical longitude, (2) astronomical latitude, (3) norm of gravity acceleration, and (4) geoid from GPS/Leveling in the geographical region of Iran. Based on the numerical results EGM96 and PGM2000A perform almost the same in synthesizing the aforementioned gravity functionals in the geographical region of Iran.


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