Author(s): Quentin Fiacre Togbevi; Yacouba Yira; Aymar Yaovi Bossa
Linked Author(s):
Keywords: Climate change; Hydrological modelling; SWAT; CORDEX-Africa; Benin
Abstract: This study assessed the impact of climate change on discharge in the Ouriyori catchment (North-West, Benin) using five Regional Climate Models (RCMs) of CORDEX-Africa database and the semi-distributed hydrological model Soil and Water Assessment Tool. To that end, the RCMs were downscaled, bias corrected and used as climate inputs in the calibrated and validated SWAT model while other data were kept. Then, the outputs of simulated hydrological and climatic variables of the future period (2021-2050) were compared to that of the reference period (1976-2005) under two climate scenarios, RCP4.5 and RCP8.5. Results indicated a decrease in future precipitation (-44.6 to -0.8%) under RCP8.5 and a mixed trend (-3.6 to +6.4%) under RCP4.5 in comparison with the reference period. In addition, the climate model ensemble projected an increase in mean monthly temperature (0.6˚C and 3˚C) and (0.8˚C and 3.4˚C) under RCP4.5 and RCP8.5 respectively. As for the mean annual discharge change, the climate model ensemble projected a significant increase of about 29.8% under RCP4.5, while a decrease up to 59.7% is depicted under RCP8.5. Therefore, adaptive strategies are needed to cope with both projected increase and decrease in discharge that can potentially lead to water shortages or floods in the Ouriyori catchment.
Year: 2024