地球重力场空间探测: 回顾与展望

地球重力场的科学数据在地球测绘学、冰川学、陆地水循环、固体地球物理、灾害监控及国防军事等领域具有重要应用价值. 美、德合作研制的地球重力场反演与气候实验(gravity recovery and climate experiment, GRACE)卫星, 有力地推动了地球重力场测量、反演和应用. 为进一步提高重力卫星科学数据的时、空分辨率, 扩展应用领域, 中国及欧美等国都考虑发射升级的重力卫星, 即后GRACE 计划(GRACE-follow-on). 本文将简单回顾重力卫星的发展历程, 介绍重力卫星的数据采集技术和反演方法, 亦着重阐述后GRACE计划的测量方法学、关键技术及预期结果. 

Mapping Earth's gravity in space: Review and future perspective

The distribution of earth’s gravity field not only changes along with the altitude, latitude, crustal composition and mantle depth, but also varies together with the continental drift, glacier evolution, ocean current, underground water changing and phenomena of ice and snow. Therefore, the scientific data of earth’s gravity field is essential to many research fields, such as the geological hazard monitoring, geodetic survey, glaciology, hydrologic circle, solid earth physics and national defense. The measurement, recovery and application of gravity of earth were greatly promoted by the development of gravity satellite missions, for example the GRACE (Gravity Recovery And Climate Experiment) mission. In order to improve the temporal and spatial resolution of satellite gravity data, China, USA and European countries were considering launching upgraded gravity satellite missions, namely the GRACE-follow-on mission. The basic idea is to employ the laser interferometer
measurement system to replace the GRACE’s microwave ranging system.In addition, the drag-free technics is introduced to eliminate the disturbance of non-inertial
forces posed upon laser measurement system. A brief history of the development of gravity satellite missions and the earth gravity recovery techniques were reviewed here. The measurement methodology, key technologies and expected results of next generation GRACE mission were also slightly touched upon.