Satellite Observed Groundwater Decline in Southern and Western Iraq

الملخص

    Over the past 20 years rainfall deficits in Iraq and the Middle East have directly depleted groundwater reserves relied upon for drinking water, Industry and  Agricultural irrigation. In this research we used the satellite data collected from the satellite of Gravity Recovery and Climate Experiment (GRACE) and GRACE-FO mission to assess fresh water storage depletion in southern-western of Iraq covering parts from Tigris-Euphrates river basins as well as the western desert from(January 2010 to January 2025). GRACE/GRACE-FO satellite data reveal a significant and  alarming decline in total groundwater reserves at a rate of approximately -28.6 ± 0.9 mm/year in water equivalent representing a total loss of 279 km³ over the 15-year study period. By integrating additional information from remote sensing satellite data analysis and Earth surface model outputs the analysis identifies groundwater depletion as the primary contributor to this depletion. This methodology represents the "best possible options" for regions like southern and western Iraq where data access is often extremely limited due to the complexity of the calculations. The results show a groundwater level decline of 19.4 ± 2.5 mm per year or the equivalent of 126.8 ± 16.3 cubic kilometers in volume during the study period.