Geodetic Reference Surface Elements || Geoid- MSL- Ellipsoid || Gravity Roles

Learn the true differences between the Geoid, Mean Sea Level (MSL), and the Ellipsoid and how each is used in modern geodesy, GPS, and surveying. This video clearly explains why the geoid is a gravity-based surface, why MSL varies from place to place, and why the ellipsoid is used as the global mathematical model for positioning. Understand how heights are determined, why geoid undulation exists, and how GNSS converts ellipsoidal heights into practical orthometric heights. Perfect for surveying students, GIS professionals, and anyone trying to understand Earth’s vertical reference systems. #Geoid #MeanSeaLevel #Ellipsoid