Future precipitation changes in the Central Ethiopian Main Rift under CMIP5 GCMs

Abstract

Abstract The purpose of this study is to predict future changes in precipitation in the Central Ethiopian Main Rift, which is vulnerable to climate change. The Long Ashton Research Station Weather Generator (LARS-WG) model was applied to project precipitation based on five global climate models (GCMs) (EC-EARTH, MIROC-ESM, HadGEM2-ES, INM-CM4, and CCSM4) from Coupled Model Intercomparison Project phase 5 (CMIP5) under two representative concentration pathways (RCP4.5 and RCP8.5) in the periods of 2041–2060 compared to the baseline period of 1976–2005. The model's calibration and validation results showed that it could predict future precipitation. According to the analysis, the mean rainfall is expected to increase in January (up to 14.2%) and December (up to 27.8%) under the RCP 4.5 and RCP 8.5 scenarios, respectively. However, a drop is anticipated in June (up to 8.2%) and May (up to 7%) under the RCP 4.5 and RCP 8.5 scenarios, respectively. In both scenarios, summer precipitation (usually the rainy season) is predicted to fall, while winter precipitation (usually the dry season) is expected to climb. Furthermore, annual and spring precipitation forecasts are anticipated to decrease in most locations. The findings of this research will be utilized to guide future water resource management in the study region.