The Impact of Climate Change on Jiroft Spring Wheat Yield Using Radiative Forcing Scenarios.

Iran is considered one of the most arid and semi-arid regions in the world, where wheat accounts for about 65-70% of the cultivated land for the main crops. To predict the impact of climate change on the yield of fall wheat (blue) in Jiroft, the Aquacrop crop model was used to simulate fall wheat yield in this study. Then, 17 general atmospheric circulation models from the CMIP5 model suite were used under the RCP4.5 and RCP8.5 radiative forcing scenarios to show changes in climate variables from 2020 to 2098. The results of these models were fine-tuned using the MarkSimGCM climate generator. Evaluation of the accuracy of the AquaCrop model in simulating wheat yield during the baseline period (1990-2016) compared to the observed yield shows the optimal accuracy of this model with R2, MAE, RMSE, and MAPE coefficients of 0.7, 203, 237, and 11.43 percent.The results of predicting wheat yield in the future period show that it will increase under both scenarios, that the average yield increase in the future period compared to the base period is 75 kg/ha for RCP4.5 and 91 kg/ha for RCP8.5. The reason for the yield increase in this product is the reduction of minimum and maximum temperatures in the future period, especially at the end of wheat growth, and the reduction of heat stress.