Evaluation of Changes in Meteorological Parameters in Atrak Basin Considering Climate Change Status

Projection of climate change in basins is very important for determining water capacity, water resources management as well as watershed management studies and environmental hazards. Therefore, in this study, temperature and precipitation changes were projected in Atrak basin, in the northern Khorasan province. For this purpose, the output projection of canESM2 global model were used considering three scenarios of Representative Concentration Pathway (RCP) 2.6, RCP 4.5 and RCP 8.5 using SDSM as downscaling model and temperature and precipitation changes in the period (2021-2050) were compared with the base period (1995-2019). For calibration and validation of SDSM model, station observational data and NCEP/NCAR data were evaluated. MAE, MSE, RMSE and R2 correlation indices were determined to clarify the performance of the model. The results showed that the SDSM model has a high ability to simulate temperature and precipitation changes in the study area. According to the results of the CanESM2 model, in the future periods, temperature and precipitation would be increased compared to the base period, which might be from 0.9 and 1.0 degree Celsius for minimum and maximum temperatures, respectively. Most of the temperature changes would be related to the eastern parts of the study area while, the amount of precipitation in the basin would be increased from 1.5 up to 11.7 percent, the largest increase of which would be related to the central and northern regions of the basin. The highest and lowest temperature and precipitation changes in the basin are predicted based on RCP 8.5 and RCP 2.6 scenarios.