Predicting temperature and solar radiation by SDSM model based on RCP scenarios(Case Study: Gharakheil synoptic station)

Suitable prediction of climatic parameters is considerably important for adapting to climate change and mitigating vulnerabilities in local scales. In current research, for climate change assessment, the CanESM2 model in the 5th IPCC report and Statistical down scaling model (SDSM) was used under three scenarios: RCP2.6, RCP4.5 and RCP8.5. The input data were minimum and maximum temperature and solar radiation of Gharakheil synoptic station in Ghaemshahr and NCEP data (National Environmental Prediction Center) for the base period (1984-2005). Sunshine hours were converted to solar radiation using adjusted Angstrom formula for climate condition of the north of Iran. Future climate scenarios were then developed for early-future (2011–2040), medium-future (2041-2070) and late-future (2071-2100). The results showed that during these periods, solar radiation, maximum temperature and minimum temperature will increase by 4-9 %, 5-24% and 8-34% compared to the base period. The largest increases (5.30c and 4.20c for maximum and minimum temperatures respectively, and 1.3 Mj/m2 for solar radiation) will occur during late future period under RCP8.5 scenario. Since temperature and radiation are the main affecting factors for crop growth and yield simulation, the planning is essential in order to choose the appropriate planting date to adapt to climate change in the study area