Climatic Variable Forecasting for Future Decades in South East Area of Iran

In recent decades, rising global temperatures have upset the climate balance of planet and caused widespread climate change in most parts of the world, known as climate change Index. In the present study, climatic variables in six synoptic stations in the southeastern part of Iran (Zabol, Zahedan, Khash, Iranshahr, Saravan and Chabahar) from 1987 to 2019 were studied in two time periods (2021-2040 and 2041-2060), considering the uncertainty of the general circulation model (Hadcm2) was investigated and analyzed. After reviewing and evaluating the model, the values ​​of climatic variables in two scenarios, RCP2.6 and RCP8.5, were scaled in the studied periods. The results of LARS-WG model accuracy evaluation in simulation of climatic variables based on MAD, RMSE, MSE, MAPE indices in the southeastern part of Iran in the validation stage showed that there was a large correlation between the simulated values ​​and the base period. Based on the output results of LARS-WG model, it shows the increase of temperature in all stations in the two studied periods. The rate of temperature increase in coastal areas is less than other land areas. Temperature changes fluctuate uniformly and precipitation changes fluctuate at all stations. The amount of rainfall during the winter and spring seasons in all stations is increasing; Future climatic conditions such as number of frosty days, number of hot, dry and wet days were calculated and the results showed that in the next period, the number of hot days, the number of dry days will increase compared to the base period and the number of frosty days will decrease. If we do not adhere to the reduction of greenhouse gases, the increase of climatic variables, the minimum temperature and the maximum temperature and the decrease of precipitation will increase in the 2041-2060 decade. Monthly forecasts for future periods in the mentioned scenarios also indicate that the warmest month in the province is on average in summer (July), the coldest month in winter (December and January), the most precipitation in winter and spring (December, January and March) and evapotranspiration peaks in summer. Finally, the results show the trend of increasing temperature and decreasing rainfall in the coming decades in the southeastern regions of Iran.