Potential Impacts of Climate Change on the Al Abila Dam in the Western Desert of Iraq

The potential impacts resulting from climate change will cause significant global problems, particularly in underdeveloped nations where the effects are felt the most. Techniques for harvesting water such as small dams provide an alternative supply of water and are adaptive solutions to deal with water scarcity in the context of future climate change. However, it is difficult to determine how rainwater harvesting (dams) may be impacted by climate change since general circulation models (GCMs), widely utilized for predicting potential future climate change scenarios, work on an extremely large scale. The primary aim of this research was to quantify the effect of climate change on water availability at the catchment scale by statistically downscaling temperature and rainfall from the GCMs. Then, using a water harvesting model, the performance of the Abila Dam in Iraq’s western desert was evaluated in both the current climate (1990–2020) and various future climate change scenarios (2020–2100). Precipitation generally decreases as the annual temperature increases. To simulate future water availability, these changes in meteorological factors were incorporated into the water harvesting model. In total, 15% or less of net storage might fulfil the whole storage capacity during the baseline period, whereas it is 10% in RCP 2.6 in 2011–2040 for future scenarios. In contrast, RCP 8.5 will be able to meet water needs at a pace of 6% in 2011–2040. The findings of this study proved that the Al Abila dam will be unable to supply the necessary water for the area surrounding the Al Abila dam in the future scenarios.