Impact of Climate Change on Crop Irrigation Requirements in Arid Regions

The nations that comprise the Gulf Cooperation Council (GCC) are located in one of the most water-stressed regions in the world. This region has faced serious socioeconomic and environmental development issues as a result of its increasing water demand over time. The extreme aridity, high rates of evaporation, and scarcity of nonrenewable groundwater resources in the GCC countries pose a significant threat to food security. This study aims to explore the impact of climate change on the potential availability of irrigation water in the State of Kuwait, which serves as an example of all GCC nations. A modeling scheme using CropWat8 was developed to study the impact of four climate change scenarios (encompassing the past, present, and future) on the net and gross irrigation water requirements (NIWR and GIWR) for selected agricultural crops, while also determining optimum irrigation schedules. Scenario 1 represented past climate conditions (1996–2006), while Scenario 2 represented the current situation (2007–2021). Projected scenarios (3 and 4) were analyzed using Representative Concentration Pathways (RCP) 4.5 and RCP 8.5, which were adopted by the IPCC to project the concentrations of greenhouse gases (GHG) emissions for 2060. The simulation results showed that compared with the current GHG levels, the increase in GHG emissions also increased the demand for NIWR by a minimum of 8.2% and a maximum of 15% for the same agricultural areas and cropping patterns. The measured GIWR in the field was 1915 m³, while the simulated NIWR was 1724 m³. With a drip irrigation efficiency of 90%, the model adequately demonstrated the validity of the CropWat8 package for simulating the climate impact on crop water requirements with a precision of approximately 92.2%. These findings suggest that the GCC countries should develop strategies to minimize GHG emissions and adopt innovative solutions for better management of water resources.