viiteellipsoidti

viiteellipsoidti is a term that appears to be a misspelling or a compound word with unclear meaning in standard geographical or surveying contexts. The standard term for a reference shape used in geodetic calculations is a reference ellipsoid. A reference ellipsoid is a mathematically defined surface that approximates the shape of the Earth. It is typically an oblate spheroid, meaning it is flattened at the poles and bulges at the equator.

Reference ellipsoids are fundamental to geodetic datums, which are the reference frames used to define positions on Earth. Different reference ellipsoids have been developed over time to better fit the Earth's shape and serve specific regional or global needs. Examples include the WGS 84 (World Geodetic System 1984) ellipsoid, which is widely used for GPS, and the GRS 80 (Geodetic Reference System 1980) ellipsoid.

The parameters that define a reference ellipsoid are its semi-major axis (the equatorial radius) and its inverse flattening. These values, along with the Earth's gravitational field, are used to calculate coordinates in systems like latitude, longitude, and height. The term "viiteellipsoidti" does not correspond to any established geodetic reference ellipsoid or concept in the field. It is likely a typographical error or a localized, non-standard term.