Impacts of climate change on stream flow and water availability in Anger sub-basin, Nile Basin of Ethiopia

This study focused on analysis of response of stream flow and water availability that may happen due to climate change in the case of Anger sub-basin (8001.28 km²) in the southern part of the Upper Blue Nile River Basin. A single GCM from Coupled Model Inter-comparison Project Phase 5 with single regional climate model and delta change bias correction approaches combined with SWAT hydrological model were used to project stream flow for the developed scenario over the study periods of 2020s and 2080s including the current conditions. The result indicates that inconsistent increasing or decreasing of water availability was observed. The total annual surface water resource potential of Anger sub-basin estimated at the base period according to this study was about 3.396 BCM/year at current situations. However, the future scenarios in 2020s increasing water availability are shown by 2.71% for RCP 4.5 and negligible decrement shown by 0.14% for RCP 8.5 scenarios. As well as decreasing of water resource was shown by 7.43% and 11.3% at 2080s for both RCP 4.5 and RCP 8.5 scenarios, respectively. This is indicative of the likely future response of stream flow of the study area.