Space-Based Gravity Data Analysis for Groundwater Storage Estimation in the Gangetic Plain, India

Monthly, seasonal and annual hydrologic signals obtained by Gravity Recovery and Climate Experiment (GRACE mission) satellites are analysed and compared with storage variables of soil moisture signatures of Monsoon Asia Integrated Regional Study (MAIRS) mission and groundwater level information of Central Ground Water Board, to observe depletion trends of groundwater in the Gangetic plain, at regional scale. While the seasonal time-series showed seasonality in the groundwater storage change, the annual trends depict a decline in this region. Further, the results showed that groundwater storage had declined at a rate 3.33 mm/month from 2005 to 2010. These time-series comparisons of storage variables have agreeable R² (coefficient of determination) and r (correlation coefficient) at various temporal cycles.