Long-term gravity changes in Chinese mainland from GRACE and ground-based gravity measurements

:A long-term (9 years) gravity change in Chinese mainland is obtained on the basis of observations of the ground-based national gravity network. The result shows several features that may be related to some large-scale groundwater pumping in North China, glacier-water flow and storage in Tianshan region, and pre-seismic gravity changes of the 2008 Ms8.0 Wenchuan earthquake, which are spatially similar to co-seismic changes but reversed in sign. These features are also shown in the result of the satellite-based GRACE observation, after a height effect is corrected with GPS data.