Compensating method of the height anomalies for ultra-high Earth's gravity field model

Abstract

An ultra-high order Earth's gravity field model,such as EIGEN-6C4 and EGM2008, the order and degree of its expansion are limited, there will be a certain truncation error. RTM residual height anomaly can by high-resolution SRTM data and DTM2006.0 data using prism integral method is calculated. The experiment results show that (1) RTM residual height anomaly before fitting makes all the standard deviation of the EIGEN-6C4 and EGM2008(2190 order) model to be increased by 5.7 mm, the contribution rate of the truncation error of 10% and 7% respectively (2) RTM residual height anomaly after fitting makes their standard deviation to be increased 1 cm and 3.3 cm respectively, the contribution rate of truncation error of the model were 2% and 6% respectively.(3) RTM height anomaly changes with the increase of integral radius, its value tends to be stable, converge to 2 cm, EIGEN-6C4 and EGM2008 model elevation changes within 110 km radius of integral and are within 105 km of centimeter level. (4) RTM technology is a kind of an effective compensation method for ultra-high order Earth's gravity field model accuracy, help to improve the accuracy of the quasigeoid.