Groundwater Overdraft and Climate-Driven Land Subsidence in the Sulaimani-Sharazoor Basin, Iraq: Insights from InSAR Techniques

The lack of extensive quantitative monitoring hinders the assessment of global groundwater depletion and its impacts. This study integrates satellite data to evaluate surface subsidence in the central part of the Sulaimani-Sharazoor Basin from 2017 to 2024, linking groundwater extraction, climatic factors, and land use changes to surface displacement. Sentinel-1 SAR data, comprising 91 pairs of single-look complex (SLC) images, were processed using the European Space Agency Sentinel Application Platform (ESA SNAP) toolbox and Differential Interferometric Synthetic Aperture Radar (DInSAR) to quantify subsidence. Results reveal significant subsidence in unconsolidated aquifers, driven by groundwater extraction, drought, and extensive well drilling. Vertical displacement might have peaked at -27 cm in 2021 and -26 cm in 2017, coinciding with periods of decreased annual precipitation and limited surface drainage. Surface displacements may have decreased by -6 cm in 2018 and -3 cm in 2019, respectively, indicating heightened rainfall and recharge rates. Urban areas experienced infrastructure damage, while agricultural areas and water bodies contributed to irregular displacement patterns. The study highlights groundwater extraction as a major driver of subsidence, exacerbated by climatic variability and land use changes. The statistical examination of the variable data revealed that all essential parameters remained within acceptable bounds, thereby bolstering the study's validity. These findings underscore the need for sustainable groundwater management and enhanced monitoring to mitigate subsidence risks in the area and similar regions.