Assessment and prediction of climate change in the next decade, by downscaling General Circulation Models (GCMs)

This study predicted amount of precipitation and temperature by using atmospheric General Circulation Models, simulation of climate in the periods 2070-2099 and 2020-2049 in Babolsar, Gorgan, Ramsar, Qazvin, Rasht, Zanjan and Tehran synoptic stations. In order to prepare climate scenario for the future was used of outputs from general circulation model HADCM3, A2 and B2 scenario. General circulation models have a low precision; further the small-scale model of the SDSM was alternated. And then the method of Domarten for the determination of future climatic were used. The results of the prediction of climate parameters indicated that the model well simulated climate parameters. Results of precipitations at all stations in the study period 2020- 2049 compared with the period 1979-2008 and showing an increasing trend in all stations; the period 2070-2099 compared to observation periods and results show the increasing in precipitation; but with decreasing trend with the periods was 2020-2049. In the 2070-2099 and 2020 – 2049 periods, maximum, minimum and maximum temperature relative to the observation period 1979-2008 has increased. The results of the climate determination by Domarten method has showed climate in the Babolsar, Qazvin, Ramsar and Rasht station compared to climate observed to 1979-2008 in future periods will not change. In the Gorgan station at periods 2070-2099 under the A2 scenario climate from Semi-arid will change to arid climate. In the Zanjan station at periods 2020-2049 under the A2 scenario climate from Semi-arid to Mediterranean climate and at periods 2070-2099 climate from Mediterranean will change to Semi-arid climate.