Groundwater storage change and driving factor analysis in north china using independent component decomposition

North China (NC) is faced groundwater shortage in the past decades. To understand the characteristics of Groundwater Storage (GWS) change in NC, GWS Anomaly (GWSA) is analyzed by using Independent Component Analysis (ICA) with the high-resolution time-variable gravity field model Tongji-RegGrace2019 and hydrological models. According to the spatiotemporal characteristics of Independent Components (ICs), the driving factors and corresponding driving mechanism of GWS changes are further investigated. Results show that the GWS in NC is decreased with a rate of −0.87 ± 0.04 cm/yr from January 2004 to December 2015 and the rate increased to −3.71 ± 0.49 cm/yr from January 2014 to December 2015. Among the first four ICs of GWSA, the first and second ICs (IC1 and IC2) cooperatively reflect long-term and intra-annual GWS changes caused by water consumption of coal mining and agricultural irrigation in northern and southern Shanxi province, with the correlation coefficients of −0.91 and −0.85, respectively. IC3 indicates the signal of semi-annual GWS change related to agricultural irrigation water consumption in southern Hebei province, with a correlation coefficient of −0.85. Besides, IC4 suggests the effect of monsoon precipitation and evaporation in front of Taihang Mountain. Hence, the driving factors, including uneven spatiotemporal distribution of precipitation, intense seasonal evaporation, severe loss by coal mining, coupled with exhaustive exploitation for irrigation, jointly restrict the GWS rise and fall at different time nodes.