干旱区生态环境知识资源中心

The first version of IGG-CAS series temporal gravity field model is recovered in this paper using GRACE data with a software named ANGELS (ANalyst of Gravity Estimation with Low-orbit Satellites) which is based on short-arc approach, and compared with the RL05 version of temporal gravity models from three famous research institutes well known in satellite gravity research, including the CSR (Center for Space Research), GFZ (GeoForschungs Zentrum), and JPL (Jet Propulsion Laboratory). The accuracy of IGG-CAS model is close to RL05, according to the geoid height comparison per degree. After applying the same de-stripe and Gauss filter to the four series temporal gravity models (IGG-CAS, GFZ, CSR and JPL) from Jan 2004 to Dec 2010, the time signal of continental water recovered from those four models are very similar. Especially, the correlation coefficients of the signal of Yangtze River valley among the four models are higher than 0. 8. The square roots of the signals in Sahara desert region from the IGG-CAS, CSR-RL05, GFZ-RL05, and JPL-RL05 are 1. 5 cm, 1. 1 cm, 1. 1 cm, and 1. 2 cm in terms of equivalent water height, respectively. To sum up, it shows that the IGG-CAS model reaches almost the same accuracy level when compared with the kind of products which are released by other famous institutes in the world (CSR, GFZ and JPL).