Thirteenth International Conference on Climate Change: Impacts & Responses

Abstract

The relevance of agriculture to the promotion of sustainable development largely depends on the availability of water resources. Climate change affects the availability of water resources by altering the magnitude of surface runoff, aquifer recharge, and river flows. This study evaluates the potential impacts of climate change on a watershed hydrological process of Finchaa catchment. The coordinated regional climate downscaling experiment (CORDEX)-Africa was used based on high emission scenario (RCP8.5) and medium emission scenario (RCP4.5). Soil and Water Assessment Tool (SWAT) hydrological modeling was used to evaluate climate change impacts. The results show that the decrease in precipitation varies from -8.24% to -11.32% under RCP4.5 and -7.87% to -9.67% under RCP8.5 for 2021-2050 and 2051-2080, respectively. The maximum and minimum temperatures will be increasing under both RCPs. The decline of precipitation and increase of temperature will lead to reduced surface flow, groundwater and water yield. The decline of surface runoff ranges from 7.34% to 14.48% under RCP4.5 and 9.3% to 12.32% under RCP8.5. The overall decline of annual flow is due to the decline of the seasonal flows under both scenarios. This could bring the reduced availability of water for crop production which will be a chronic issue of subsistence agriculture. The sensitivity of the hydrological process to the climate changes show the discrepancy between supply and demand will become higher owning to the high variability of temperature and higher evaporation demands. Consequently, strong climate-resilient water management policies will be required to manage the risks.