Geodetic References: Coordinates and Systems

This lecture covers the theoretical aspects of geodetic references, including the definition of coordinate systems, the dynamic nature of the Earth, and the realization of geodetic systems. It also discusses Cartesian geocentric coordinates, coordinates on the ellipsoid, the geoid as a reference surface for altitudes, and the relationship between the geoid and the ellipsoid. The instructor explains the importance of known and documented points, the influence of gravity on the geoid, and the quantification of geoid variations. Additionally, it addresses different geodetic reference systems such as CH1903+ and ITRS, emphasizing the need for specifying the reference system for accurate measurements.

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