低轨道人造卫星(CHAMP、GRACE、GOCE)与高精度地球重力场——卫星重力大地测量的最新发展及其对地球科学的重大影响

评述了卫星重力大地测量的最新发展及其对地球科学的重大影响。为了更好地理解地球内部物理构造与海洋动力学，以及大陆，冰川和海洋的相互作用，改善现有地球重力场模型（包括精度和空间解析度）是非常重要的。IUGG等国际组织对此已经强调了很多年。最近，由德国的GFZ（GeoForschungsZentrum)，美国的NASA（National Aeronautics and Space Adminitration)以及欧洲宇航局ESA（European Space Agency)开发研制了最先进的地球监测技术－SST（Satellite-to-Sateilite Tracking)。其主要特点是利用现有的GPS连续追踪新发射低轨道卫星，并由低轨道卫星对地球重力场作精密观测。已经发射和即将发射的卫星有3颗：GHAMP（Challenging Mini-Satellite Payload for Geophysical Research an Application)已经于2000年发射；GRACE（Gravity Recovery and Climate Experimert)定于2002年发射；GOCE（Gravity Field and Steady-state Ocean Cirulation Explorer)计划2004年发射，它们可以统称为重力卫星。载有SST技术的人造卫星的主要目的是获得具有前所未有的高精度和高空间解析度的全球重力场和大地水准面模型，加强人们对地球内部构造的理解并为海洋和气象研究提供更好地参考。上述3个重力卫星工作在有明显区别的不同波谱内，它们有不同的科学应用，仅有一小部分重合。所以，就应用而言它们是完全互补的。它们在地球科学中的应用将是广泛的，特别对于固体地球物理学，海洋学以及大地测量学等领域，它们将会带来革命性的变化，其意义不亚于GPS。

SATELLITE IN LOW ORBIT(CHAMP,GRACE,GOCE) AND HIGH PRECISION EARTH GRAVITY FIELD:the latest progress of satellite gravity geodesy and its great influence on geoscience

The latest progress of satellite gravity geodesy and its great influence on geoscience is reriewed in this paper.In order to comprehend the physical structure of the earth's interior,ocean dynamics and the mutual action of continent,glacier and ocean, it is very inportant to improve the available models of earth's gravity field(including accuracy and spatial resolution),on which several international organizations have emphasised for many years.Lately GFZ(GeoForschungsZentrum) of Germeny,NASA(National Aeronautics and Space Adminitration) of The United States and ESA(European Space Agency) of Europe developed the most advanced earth monitoring technique--SST(Satellite to Satellite Tracking),whose major characteristics are continuously tracing the satellites in low orbit launched at late by use of available GPS and the precision observation for earth's gravity field from the satellites in low orbit.There are 3 satellites launched or will be launched,CHAMP(Challenging Mini Satellite Payload for Geophysical Research and Application) launched in 2000,GRACE(Gravity Recovery and Climate Experiment) is scheduled to be launched in 2002 and GOCE(Gravity Field and Steady state Ocean Circulation Explorer) in 2004,they are all called as gravity satellites.The main objectives of satellite carrying SST equipment are to obtain the gravity field and geoid model of the earth, to strenthen the understanding of earth's inner structure and to provide a better reference for the study of ocean and atmosphere.The above 3 gravity satellites work in obviously different spectrums and apply in different scientific fields with a little overlap,hence they are mutually complementary and widely applied in the geo science.It is certain that these satellites,like GPS,will bring the revolutionary change to solid geophysics,oceangraphy,geodesy and so forth.