Detection and Attribution of Climate Change Effects on Entered Runoff to Karaj Dam in the past periods

One of the most important consequences of Climate Change is the changing of climatic variables and the effects on hydrological variables and water resources. Karaj Dam is one of the important sources of water and electrical energy for Tehran and Alborz province. Thus, diagnosis of affective factors on the water resources of upstream of this catchment and entered runoff to Karaj dam could be vital for planners and policy makers for the future periods. One of the best methods for diagnosing the effects of Climate Change on climatic and hydrological variables is Detection and Attribution with Optimal Fingerprint approach. In this research have been tried to detect and attribute the ALL, GHG and NAT signals by simulations from CanESM-2.0 model. Therefor every signal has been downscaled with MRQNBC method, and then simulated with SWAT calibrated model for selected signals for (1985-2011). At last those entered to optimal fingerprint method. By attention the results, just GHG signal (which shows the globe under the effects of Greenhouse gases without the other forcing has been detected and attributed and its scaling factor (β) got 0.76. While two other signals (ALL, NAT) haven’t been detected and attributed. In other words the changing of entered runoff to Karaj dam was very likely consonant with simulated runoff which affected from GHG signal only.