Considerable carbon dioxide emissions from groundwater over-exploitation in the North China Plain

This study compiled hydrogeochemical data from 6202 groundwater sampling sites across the NCP, being sampled between 2007 and 2010. This dataset comprises 4454 points in shallow aquifer and 1748 points in deep aquifer, which were used for the analysis of the hydrogeochemical characteristics and the quantitative calculation of CO2 emissions induced by groundwater over-exploitation in the NCP. Given the absence of continuous hydrogeochemical monitoring throughout the study period, these samples provided the representative hydrochemical baseline for the entire timeframe.