卫星对地观测技术极大推进了地球重力学的发展及其在地球科学中的应用，在地球动力学、地震学和全球气候变化研究领域取得一系列瞩目的成果。基于卫星对地观测技术，可获得全球1"×1"分辨率的数字高程模型和1'×1'分辨率的海洋重力异常，由此，构建10800阶地球重力场模型成为可能。本项目拟研究数字高程模型精化技术和方法，开展利用数字高程模型恢复陆地短波重力异常的技术攻关，重点研究浮点数扩展指数方法，实现10800阶球谐展开的并行快速计算，发展新的椭球谐递归比率算法，实现10800阶椭球谐第二类勒让德函数及其一阶、二阶、三阶导数的快速稳定递推数值解法，构建10800阶球谐展开数字高程模型和椭球谐展开地球重力场模型，形成一整套10800阶球谐/椭球谐分析与综合的理论算法和软件系统。本项目为解决资源、环境和灾害等问题提供重要的高分辨率高精度重力场信息，并推动地球物理学、地球动力学和海洋学等相关学科的发展。

The satellite Earth observation technology have vastly boosted the development of gravitation and its application in Earth-related fields, which have made a series of remarkable achievements in geodynamics, seismology and global climate change researches. Based on the satellite Earth observation technology, the global 1"×1" digital elevation model (DEM) and 1'×1' marine gravity anomaly can be obtained. Thus, it is possible to construct the 10800 degree and order Earth gravity field model. This project intends to study the refinement technology and method of DEM, carry out the technical research of using DEM to recover land shortwave gravity anomaly. Focus on the extending exponent of floating point numbers and based on Driscoll/Healy integral and Gauss-Legendre integral, the parallel and fast calculation of 10800 degree spherical harmonic expansion is realized, and a new ellipsoidal harmonic recursive ratio algorithm is developed to realize the fast and stable recursive numerical calculate method of 10800 degree ellipsoidal harmonic Legendre functions of the second kind and their first-degree, second-degree and third-degree derivatives. The DEM of 10800 degree and order spherical harmonic expansion and the gravity field model of ellipsoidal harmonic expansion are constructed, and a set of theoretical algorithms and software systems for 10800 degree spherical/ellipsoidal harmonic analysis and synthesis are formed. This project can provide high-resolution and high-precision gravity field information for modern geoscience to solve the problems of resources, environment and disasters, and promote the development of seismology, geophysics, geodynamics and oceanography.