Gravity prediction using collocation and taking known mass density anomalies into account

Summary. The anomalous (gravitational) potential of the Earth, T , is split in two parts, T= T ^C + T _M. Here T _M is a harmonic function generated by known mass density anomalies and T ^C =T-T _M. This function will also be a harmonic function, which therefore may be approximated using the method of collocation, based on known gravity anomalies or altimeter derived geoid undulations, for example. Gravity anomalies can then be predicted using the known linearized relationship between T and Δ g . This procedure may give a 40–50 per cent increase in the precision of the prediction results as compared to a procedure where mass density anomalies are not taken into account.