Impact of climate change on hydrological response of Mojo river catchment, Awash river basin, Ethiopia

Abstract

Climate change is a change in the state of climate identified by a change in temperature and precipitation that affect the hydrology of basins. This study has investigated the effects of climate change on the stream flow of Mojo River Catchment using (CORDEX)-Africa data outputs under RCP4.5 and RCP8.5 scenarios. Three-time horizons: near period (2006–2031), mid-period (2031–2055), and far period (2056–2080) were used. The SWAT model was used to simulate runoff. From the MIROC-MIROC5 Model result, the mean annual precipitation is increasing under RCP4.5 and decreasing under RCP 8.5. Similarly, the mean annual temperature shows an increasing trend for both scenarios. The mean annual streamflow shows a decreasing trend in the near and mid-future under both scenarios and only increases (by 6.31 m3/s) in the far future under RCP8.5. For MPI-M-MPI-ESM-LR, the mean annual precipitation shows a decreasing trend under RCP 4.5 and increasing under RCP 8.5, but the mean annual temperature becomes increasing for both scenarios. However, streamflow shows an increase under both scenarios in the all-time horizons and decreases (by 6.68 m3/s) under RCP 8.5 in the near and mid-future. The result of this study indicates that climate change affects streamflow. Therefore, different water-based design operations should incorporate climate change scenarios.