Climate change in a region with altitude differences and with precipitation from various sources, South-Central Iran

The study area, with an arid to semiarid climate, is located in South-Central Iran. The precipitation sources are from Mediterranean, Sudan, and Indian Ocean. The daily precipitation and temperature generated by the Canadian Global Coupled Model are transiently downscaled, from 2015 to 2095, at 15 stations using LARS-WG under scenarios B1, A1B, and A2. According to our simulations, the study area will warm 2.3, 3.1, and 3.5 A degrees C and mean annual precipitation will decrease by 13, 24, and 26 % under scenarios B1, A1B, and A2, respectively. The western regions will experience greater precipitation reduction than eastern regions, due to effect of precipitation reduction in Mediterranean air mass in the future. The precipitation reduction varies among different stations due to differing precipitation depths. The duration of dry periods will increase, and precipitation depths of all wet, normal, and dry periods will decrease under three scenarios, but the reduction is higher in dry and normal periods.