Projection of temperature and precipitation in southern Iran using ECHAM5 simulations

This study applied a statistical approach to project temperature and precipitation condition in southern parts of Iran for the period 2016-2045. The applied methodology transformed the probability distribution of the observed historical series into the corresponding simulated time series of the ECHAM5 GCM model. Results showed that the mean annual temperature of the study area for the period 2016-2045 is greater than corresponding climatological mean by about 0.5-1.0 °C, if the emissions are within the range of the 20C3M scenario. These values, however, increased to about 2.0-2.4 °C when the high emission scenario of 1PTO2X was applied. We examined conformity between the trend lines of the historical temperature data and corresponding projected time series. The conformity was substantially improved when the outcomes of the 1PTO2X rather than 20C3M scenario were used. Under the 20C3M scenario, the mean values of the projected precipitation data were less than corresponding amounts of the historical time series by about 20%.