卫星测高数据的沿轨迹重力异常反演法及其应用

本文给出了一套基于直角坐标系下的垂线偏差求解重力异常公式 ,并将之发展成为一套新的沿轨迹重力异常求解公式。与其他方法相比 ,本方法无须求解交叠点处沿轨迹和跨轨迹方向的海面高斜率 ,仅需计算沿轨迹方向的海面高斜率 ,因而更为简洁、有效 ,而且分辨率可以更高并可与真正的沿航迹实际船测重力相比较、验证。据此 ,利用 Geosat/GM、ERS-1 /35天及TOPEX/Poseidon三种测高数据 ,反演了南中国海域 (0°～ 2 5°N,1 0 5°～ 1 2 2°E)的 2′× 2′重力异常—— IGG-S。通过与实际船测资料和国际同行提供的重力模型相比 ,IGG-S总体精度达到1 0× 1 0 - 5ms- 2。

Inversion of Gravity Anomalies from Along-track Vertical Deflections with Satellite Altimeter Data and Its Applications

A new gravity recovery method with along-track verticaldeflections is developed independently by authors on the basis of the Laplace's equation in Cartesian system. The method can be easily approached with 1D Hilbert transform and the along-track gravity anomalies can be derived directly from the along-track slopes of sea surface height (SSH). In other words, only along-track slope of SSH needs to be calculated other than two slopes of along-track and cross-track at crossover point. So the recovered along-track anomalies are almost the same as ship measurements along ship trajectory. The 2′×2′ gravity anomalies with an accuracy of 10×10-5ms-2 (RMS) limited in South China Sea —— IGG-S are recovered from Geosat/GM, ERS-1/35day and TOPEX/Poseidon altimeter data using the method mentioned above. From the comparisons with external data sets of SIO, KMS and Hwang, respectively, it can be seen clearly that the accuracy of IGG-S is almost the same as them.