New solutions for the geoid potential W0 and the Mean Earth Ellipsoid dimensions

• Main Author: Sjöberg L. E.
• Format: Article
• Language: English
• Published: Sciendo 2013-12-01
• Series: Journal of Geodetic Science
• Subjects: geoid datum; global vertical datum; mean earth ellipsoid; reference ellipsoid
• Online Access: https://doi.org/10.2478/jogs-2013-0031

Earth Gravitational Models (EGMs) describe the Earth’s gravity field including the geoid, except for its zero-degree harmonic, which is a scaling parameter that needs a known geometric distance for its calibration. Today this scale can be provided by the absolute geoid height as estimated from satellite altimetry at sea. On the contrary, the above technique cannot be used to determine the geometric parameters of the Mean Earth Ellipsoidal (MEE), as this problem needs global data of both satellite altimetry and gravimetric geoid models, and the standard technique used today leads to a bias for the unknown zero-degree harmonic of the gravimetric geoid height model. Here we present a new method that eliminates this problem and simultaneously determines the potential of the geoid (W0) and the MEE axes. As the resulting equations are non-linear, the linearized observation equations are also presented.