联合卫星重力和卫星测高数据确定稳态海洋动力地形

Combining altimeter and gravity satellite to compute quasi-stable dynamic ocean topography

新一代卫星重力探测任务GRACE大大提高了地球重力场模型中长波分量的精度，使得联合卫星测高平均海面分离更精细稳态海洋动力地形成为可能。本文利用T／P（1994年～2003年）和JASON-1（2003年～2005年）卫星测高数据确定了全球30’×30’平均海面高；基于重力场模型WHU-GM-05，计算得到对应于海面高的GRACE海洋大地水准面格网值；利用“移丢恢复法”和高斯滤波求得全球稳态海面地形。与EGM96、Ri005、ECCO和GGM02模型进行比较，检验结果表明GRACE任务有效的改善了海洋大地水准面的精度，使得稳态海洋动力地形能够呈现更多细部。

The new gravity explore mission GRACE,which provides significant improvement in global gravity field model of the Earth,makes separating precise mean dynamic ocean topography(MDOT) from altimeter-derived mean sea surface(MSS) possible and efficient.In this study,a new mean sea surface height model from T/P,JASON-1 altimeter data is formed with 30'×30' grid.By combining it with the latest GRACE-geoid model computed from gravity model WHU-GM-05,the mean ocean dynamic topography is determined.From the derived model,several comparisons are processed with that from earlier models(EGM96、Rio05、ECCO and GGM02).Respecting to previous models,the results show improvement of the derived MDOT is significant.