Global terrestrial water storage variations revealed by gravity mission and hydrologic and climate model

The terrestrial water storage changes (TWSC) for global scale as well as area scale can be estimated by GRACE (Gravity Recovery And Climate Experiment) mission, while hydrologic and climate model named GLDAS (Global Land Data Assimilation System) provide variations of soil moisture and snows which can also derive the TWSC. These new technologies provide new methods to monitor global terrestrial water storage variations and climate change. The global monthly TWSC have been derived from GRACE observations and GLDAS model estimates respectively, it shows there have high There have high correlations between TWSC derived from GRACE observations and GLDAS model estimates, while due to lack of information from GLDAS models, TWSC derived from GRACE observations is more reliable. The monthly mean TWSC from April 2002 to August 2011 have been derived from GRACE observations, and there has a steady condition of the global TWSC with a slowly growing rapid of 0.142±0.0028cm/year in this period. while the change range of Northern Hemisphere of TWSC is more obvious than those of Southern Hemisphere. Due to the unbalance of regional rainfall, the TWSC in the middle latitude regions are changing more significantly than those in high-and-low latitude regions. It shows great correlations between global TWSC and global land surface temperature with correlation coefficient of 0.91, while the change of land surface temperature always occurred about two months later than the TWSC, and both of them have obvious change with annual period.