Raifall-Runoff Modelling under the Climate Change Condition in Order to Project Future Streamflows of Sufichay Watershed

Two major issues through studies on hydrological impact assessment of climate change are the sufficiency of historical data and selection of the best rainfall-runoff model. Climate models، with the ability to simulate climatic variables، are considered as references for future projections. Therefore، the rainfall-runoff model must be able to simulate streamflow using only these variables. Current study addresses a methodology of choosing the best model from global climate models for impact assessments which require local-scale climate scenarios. The approach is based on the use of a weather generator which can generate the local-scale daily climate scenarios used as an input in many process-based impact models. The results of analysis of Sufichay streamflows، which flow in Urmia lake basin، by the rainfall-runoff model of IHACRES، indicated a considerable difference between the climate models under emission scenarios A2 for the future period 2046-65. There were no noticeable differences under emission scenarios B1 for both future periods (2011-30 and 2046-65) and under emission scenarios A2 for the near period (2011-30) especially in warm seasons. The uncertainty of selecting different emission scenarios was low for the period 2011-30 and high for the mid-century (2046-65).