Analysis on motion of Earth’s center of mass observed with CHAMP mission

作     者：HWANG CheinWay 

作者机构：National Astronomical Observatories Chinese Academy of Sciences Department of Civil Engineering Chiao Tung University 

出 版 物：《Science China(Physics,Mechanics & Astronomy)》 (中国科学：物理学、力学、天文学（英文版）)

年 卷 期：2008年第51卷第10期

页      面：1597-1606页

核心收录：

学科分类：070801[理学-固体地球物理学] 07[理学] 0708[理学-地球物理学] 

基　　金：Supported by the International S&T Cooperation Program of China (Grant No. 2006DFA21980) the National Hi-tech R&D Program of China (Grant No. 2006AA12z303) the National Natural Science Foundation of China (Grant No. 40774009) the Natural Science Foundation of Shandong Province, China (Grant No. Y2003E01) 

主　　题：geocenter motion CHAMP power spectral analysis wavelet transformation 

摘      要：Geocenter motion (GCM) is one important topic for constructing and maintaining the terrestrial reference frame and its applications. GCM is studied from CHAMP with the multi-step approach in this paper. Geometric orbits of CHAMP in 2001-2006 are precisely determined with the kinematic method only from the satel-lite-borne GPS zero-difference data. Then a GCM time series is estimated from the precise kinematic orbits based on the theory of satellite dynamics to fit the CHAMP’s real geometric orbits. We compare the series with the geocenter series used in ITRF2005. Then the GCM series are analyzed with Fourier transform and wavelet transformation. The mean motions within 6 years in TX, TY and TZ direc-tions are respectively 0.8 mm, 2.2 mm, and 7.9 mm. The trends of GCM in the three directions are 0.495 mm/a, -0.004 mm/a, and 1.309 mm/a, respectively. The long-term movement (2001-2006) indicates that the crustal figure is changing. The seasonal variations are the main component which may be excitated by the mass redistribution of Earth’s fluid layer, e.g. ocean, atmosphere and continental water. The inter-annual variations are also found in the GCM series measured with CHAMP.