Performance Evaluation of the CanESM2 Global Circulation Model and the REMO Regional Model to Predict Changes of Climatic Parameters in the Jazmourian Watershed

Abstract

Global warming has a serious impact on access to water resources, especially in arid regions due to changes in rainfall and temperature. The Global Circulation Models (GCM) and the Regional Climate Models (RCM) have been considered as the main tools for assessing changes in climatic variables in the future. The difference in the spatial resolution of these models causes the different results in climate change assessment. The performance of the CanESM2 and REMO models was evaluated using statistical criteria in the Jazmourian Watershed. The results indicated that the CanESM2 has performed better than the REMO regional model for predicting climatic parameters. Climate parameter simulation based on the CanESM2 model showed that precipitation will decrease under the RCP scenarios (RCP2., RCP4.5, RCP8.5) by 19.23, 18.55, 14.55 mm, respectively at the Iranshahr Station and 8.31, 10.6, 15.72 mm, respectively at the Bam Station. The mean projected temperature based on the RCP scenarios showed that temperature will increase by 1.57, 2.15 and 3.1 ºC at the Iranshahr Station and 1.84, 2.31 and 3.35 ºC at Bam station under RCP2.6, RCP4.5 and RCP8.5, respectively. Generally, the finding of simulated precipitation and temperature in the Jazmourian Watershed showed that the long dry periods is more likely to occur in the future as compared to the historical period. Hence, knowing the trend of the changes in climatic variables can help managers and planners to provide required strategies under the future climate change conditions.

Keywords

• changes trend
• jazmourian
• large-scale model
• mann- kendall
• regional model