Climate change, as one of the major challenges of the 21st century, has widespread impacts on agricultural production and food security. In this study, LARS-WG 8 models were used to generate climate data and AquaCrop 7.1 to simulate wheat yield in Khorasan Razavi Province. the effects of different greenhouse gas emission scenarios (SSP1-2.6, SSP2-4.5, and SSP5-8.5) were assessed towards 2040. The results showed that the LARS WG model performs reasonably well in generating average precipitation and temperature, but shows limitations in representing temperature variability and fluctuations. According to the results the average temperature at Sabzevar, Quchan, and Torbat-e Jam stations will increase the most in the SSP5-8.5 scenario; for example, the average temperature in Quchan will increase from 12.7 degrees in the period 2010-2024 to 14.1°C in SSP5-8.5. Future precipitation is expected to increase by 11–38 %, while reference evapotranspiration (ET0) may decline by 8–32%. The average grain yield of wheat in Khorasan Razavi Province is projected to increase by about 7 to 13% across scenarios. Water productivity (WP) has also projected to rise from 1.7 in 2023 to 1.9 and 2.0 under different scenarios.
The findings of this study indicate that climate change in the 2040 horizon could, under some conditions, lead to increased yield and water productivity of wheat in Khorasan Razavi Province. However, these increases will only be sustainable if they are accompanied by smart water resource management, selection of resistant varieties, and adaptive policies to address the risks of warming, changing rainfall patterns, and the spread of pests and diseases. Therefore, although the short-term results are promising, from a sustainability perspective, a comprehensive and forward-looking approach is required to ensure food security and agricultural resilience in the region.