Prediction of Seasonal and Monthly Changes of Evapotranspiration and Climatic Parameters by the use of Downscaling of General Circulation models HADCM3 data in both Arid and Semi-Arid Stations

Climate change impacts on climate parameters such as rainfall, temperature, evapotranspiration and water resources. The aim of this research is the evaluation of the effect of climate change on climate parameters and evapotranspiration by the use of HADCM3 model in an arid (BandarAbbas) and semiarid station (ShahraKord). In order to simulate daily data of rainfall, sun shine, max temperature and min temperature based on a stochastic method, LARS-WG downscaling tool was used. This stochastic weather generator downscaled the climate of two synoptic stations by the use of HADCM3 model and A2, A1B, B2 emission scenarios during 2011-2030. The largest increase in the amount of max and min temperature was observed under A1B scenario in July in ShahreKord station. Winter precipitation increases in ShahreKord station base on all of the scenarios that it can be referred to the strengthening of the rainfall flows systems such as Mediterranean and Sudan Ian. Increased winter rainfall inBandarAbbas station can be attributed to the strengthening of the monsoon rain system. In both of stations, evapotranspiration increased in all of months and warm seasons. This increase is more considerable in warm months. Totally impact of climate change on rainfall behavior is different in both stations, while the other parameters of both stations have similar behavior.