Nota: A tradução desta entrada está atualmente em revisão de qualidade, portanto parte do conteúdo é exibida temporariamente apenas em inglês.
Este verbete ainda não foi traduzido para o seu idioma, portanto o original é exibido abaixo.
geoid
This term describes a complex, irregular surface that represents the actual gravitational potential of the Earth. It serves as the primary baseline for geodesy, allowing scientists to determine precise altitudes by comparing a measured ellipsoidal height to the geoid height.
Because it is a specialized scientific concept, the word is used almost exclusively in technical contexts such as cartography, satellite altimetry, and geophysical surveying. It is distinct from a perfect sphere or an ellipsoid, as it accounts for the uneven distribution of mass within the planet.
Meanings
Examples
The geoid is often used as a reference surface for measuring altitude.
Wait, so the geoid is not a perfect sphere because of gravity variations?
The difference between the ellipsoid and the geoid is known as geoid height.
Satellite missions provide high resolution data to map the global geoid.
I need to understand how the geoid affects GPS altitude readings.
The geoid represents an equipotential surface of the Earths gravity field.
Imagine the entire planet covered in water at rest; that shape is the geoid.
Geodesists study the geoid to better understand the distribution of mass within the Earth.