Launched in 2002, the dual-satellite mission of GRACE (Gravity Recovery And Climate Experiment) has enabled measurement of the Earth's tiny time-variable gravity, providing new and precise information about large-scale mass transport on or in the Earth. Most of the time-variable signal comes from the Earth's fluid envelope: the oceans, the atmosphere, the polar ice sheets and continental glaciers, and the storage of water and snow on land. GRACE is a powerful tool in monitoring environmental change (sea level rise, glaciers and ice sheets melting, land water storage change and ocean currents).

Dr. Zhang Zizhang in satellite geodesy group of IGG develops a new non-isotropic filter, called the fan filter to process the GRACE data. Their latest research results has been published in Geophys. Res. Lett., vol.36,2009. Their results show the trend map of global gravity field, which contains(a):ice mass budget: mass lose in West Antarctica, ice melting in Greenland;(b)postglacial rebound in North America， Antarctica and Fennoscandia;(c)land water storage change in Amazon River, Congo River, Australia Ganges and so on;(d) the gravity change from Sumatra-Andaman Earthquake.

Fig 1. the trend of global gravity anomaly observed from GRACE satellite

 Prof. Zhong Min, Dr. Zhang Zizhang, Dr. Peng Peng and Dr. Duan Jianbin in satellite group of WHIGG have published their latest research results in Chinese Sci Bull, vol.54 2009. The authors analyzed the trend of china land water storage redistribution at medi- and large-spatial scales in recent five years by satellite gravity observations. They found the underwater mining in the North China and gravity change in Three-Gorges Dam which detected by GRACE satellite. The results is inspiring. Congratulations!

Fig 2. the trend of land water storage in China observed by GRACE satellite