This study sets out to simulate various hydrological responses to climate change. The semi-distributed hydrologic model of the Soil and Water Assessment Tool, SWAT, was used to simulate different parts of the hydrological cycles. The comprehensive assessment of the effect of climate change on runoff, crop yield, and water balance in Siminehroud and Zarrinehroud watersheds is the novelty of this research. The simulation period was from 1988 to 2014. The runoff model was calibrated using the plant parameters, and the initial crop yield was used to calibrate the model. During the calibration and validation periods, the statistical measures, namely NS and R², were obtained as 0.69 and 0.82, respectively. Using the multisite statistical downscaling of the LARS-WG climate model, we introduced the future climatic conditions as inputs to the model based on two optimistic (RCP2.6) and pessimistic (RCP8.5) scenarios. The most significant changes in the runoff in the upcoming period, was in June, reduced by 4.2 m³s⁻¹, and in May, increased by 4.8 m³s⁻¹ in the optimistic scenario. In the RCP8.5 pessimistic scenario, the most significant runoff change was observed in June and October. The results indicated that these changes would lead to a decrease in the main crops across the region.

这项研究着手模拟对气候变化的各种水文响应。土壤和水评估工具SWAT的半分布式水文模型用于模拟水文循环的不同部分。全面评估气候变化对Siminehroud和Zarrinehroud流域的径流量，作物产量和水平衡的影响，是这项研究的新颖之处。模拟期为1988年至2014年。使用植物参数对径流模型进行了校准，并使用了初始作物的产量对模型进行了校准。在校准和验证期间，统计量度，即NS和R ²分别为0.69和0.82。使用LARS-WG气候模型的多站点统计缩减，我们基于两种乐观（RCP2.6）和悲观（RCP8.5）场景，将未来气候条件作为模型的输入。在乐观的情况下，在接下来的时期中，径流最显着的变化是在6月减少了4.2 m ³ s ^-1，在5月增加了4.8 m ³ s ^-1。在RCP8.5悲观情景中，在6月和10月观察到了最大的径流变化。结果表明，这些变化将导致该地区主要农作物的减少。