Document Type : Research Paper
, Department of Irrigation and Drainage Engineering, Aburaihan Campus, University of Tehran, Iran.
Department of Water Resources Engineering, Faculty of Civil, Water and Environmental Engineering, Shahid Beheshti University, Tehran, Iran.
Department of Environmental Engineering, Faculty of Civil, Water and Environmental Engineering, Shahid Beheshti University, Tehran, Iran.
Department of Energy Systems Engineering, Faculty of Energy Engineering, Sharif University of Technology, Tehran, Iran.
Deputy of Soil and Water Conservation and Management, Department of Environment, Tehran, Iran.
The climate change effect on future precipitation (2040-2021) of Iran is investigated in this study. For this purpose, the results of three general circulation models (GCM) named GFDL-ESM2M, HadGEM2-ES and IPSL-CM5A-LR were analyzed for two scenarios of greenhouse gas emissions RCP2.6 and RCP8.5. CCT model and daily precipitation data of the base period (1986-2019) were used to downscale and bias correction of future daily precipitation data. According to the annual results, the weighted average of annual precipitation of rain gauges due to all scenarios except RCP8.5 in the IPSL-CM5A-LR model was increasing. The weighted average of seasonal precipitation in winter increased in all of the studied climate change conditions, but in other seasons the amount of precipitation decreased or increased. The highest increase in the weighted average of seasonal precipitation was in winter due to the RCP2.6 scenario and GFDL-ESM2M model (23 mm). The highest decrease in the weighted average of seasonal precipitation was in autumn due to the RSP8.5 scenario and IPSL-CM5A-LR (10.5 mm). Slight changes in mean precipitation, on the other hand, a sharp decrease in minimum precipitation (446 mm due to G3S4) and a sharp increase in maximum precipitation (233 mm due to G2S1), indicate the occurrence of severe extreme events (drought and flood) in the future.