Future Climate Change Projection over Iran using CMIP5 Data during 2020-2100

Prior to the publication of the fifth Assessment Report (AR5) by the Inter-governmental Panel on Climate Change in November 2013, our researchers used data from CMIP3 General Circulation Models for future climate change projection over the country. But by 2015, access to data from the CMIP5 series of General Circulation Models has been gradually facilitated. As most research on projection of climate change is currently being carried out using data from CMIP5 models. In this research, the output of all CMIP5 models used in AR5 reporting has been used to simulate the future climate change projection of the country. The results of this study showed that with the exception of the optimistic scenario of RCP2.6, in three other scenarios, the average precipitation from the Mediterranean to Afghanistan would decrease. In the scenario of RCP8.5reducing precipitation in the west of Iran would be approximately 20% would it will be around 30% in Syria, Jordan, Palestine and Iraq. comparing to long-term. Also, in case of non-compliance with the Paris agreement, the average temperature rise in the country is about 5.2 degree of Celsius and in the case of implementation of Paris Agreement, it will be 1.3 degrees Celsius greater than the period of 1986-86. Generally, due to lower precipitation and rising temperatures, it is expected that the western parts of the country including Zagros, will be exposed to drought, water stress, reduction of forest cover, water resources and hydroelectric plants production and increase of extreme events.