Prediction of future climate change in Tehran and Yazd under RCPs scenarios and using LARS-WG model

Climate change will change climate variables in the future. In order to reduce the negative effects of climate, it is required to project future climate variables. The purpose of this study is to simulate most realistic daily rainfall and temperature series for Tehran and Yazd, with arid climatic, in period of 2036-2065 with considering uncertainty.

the outputs of the CANESM2 under RCP scenarios were downscaled using LARS-WG. In downscaling, various characteristics of the large-scale scenarios were transferred to the downscaled scenarios. In most of the previous studies, only changes in averages have been considered. The uncertainties of emission scenarios and climatic variabilities were investigated using three emission scenarios and generating 100 series of 30-year variables for each scenario. So, a wide range of probable future scenarios is predicted and more reliable results are obtained.

The results show in the future, for both Tehran and Yazd, temperature will rise in most months of the year, while in some months it will decrease. Average maximum temperature in April will increase between 6.1 to 9.9 ºC in Tehran, and between 7.1 to 8.2 in Yazd, while it will decreases in September by 2.4 degrees in Tehran, and by 0.7 degrees in Yazd. Future annual rainfall will increase between 20% to 40% in Tehran and between 43% to 49% in Yazd. However, changes vary in different months.

Climate regime of both Tehran and Yazd can considerably change in the future. Therefore, adaptation strategies with climate change are necessary.