A gravity anomaly is the difference between the observed gravity and its theoretical value, which is calculated at the surface of a global spheroid (ellipsoid of Hayford or WGS84) by rather simple formulae (2 functions of latitude).
A gravity anomaly is the difference between the observed gravity (ellipsoid of Hayford or WGS84) by rather simple formulae (2 functions of latitude). A gravity anomaly is the difference between its theoretical value (ellipsoid of Hayford or WGS84) by rather simple formulae (2 functions of latitude). Its theoretical value is calculated at the surface of a global spheroid.