Groundwater storage changes from GRACE satellite in the Southern Gobi Region of Mongolia

Friday, 19 December 2014
Buyankhishig Nemer1, Cao Yanping2, Batdemberel Bambii Bayanzul1 and Erdenetsetseg Erka Altangerel1, (1)Mongolian University of Science and Technology, Department of Geology and Hydrogeology, Ulaanbaatar, Mongolia, (2)aCold and Arid Regions Environmental and Engineering Research Institute, Lanzhou, China
Groundwater is an important resource in the Southern Gobi Region of Mongolia because rainfall and surface water availability are severely limited and the demands are expected to increase rapidly with the development of mining and new population centers. Groundwater systems are more complex and yet its distribution and quantity are poorly known. The purpose of the research is to evaluate the potential utility of GRACE (Gravity Recovery and Climate Experiment) satellites to monitor groundwater storage in the arid area. Regional groundwater storage changes in SGR are estimated using monthly GRACE total water storage change data. Groundwater storage change estimates are compared to groundwater level measurements of 66 shallow dug wells and 72 deep boreholes for the period 2004-2012. Groundwater storage decreases during the cold season and increases during the warm season. Seasonal groundwater change calculated from GRACE total water storage is highly correlated to groundwater level measurements in shallow aquifers. There is no correlation between groundwater storage changes derived from GRACE and deep aquifer. The result indicates that GRACE can be used to monitor large area where groundwater observation is limited, especially unconfined shallow aquifers.