Impact of climate change on water availability in the Oueme catchment at the outlet of the Save's bridge (Benin, West Africa)

Amedée Chabi,Ezekiel Obada,Eric Adéchina Alamou,Abel Afouda,Eliezer Iboukoun Biao,Esdras Babadjidé Josué Zandagba

doi:10.5194/piahs-384-255-2021

Abstract

Abstract. One of the major threats to water resources today remains climate change. The objective of this study is to assess the impact of climate change on water availability in Oueme catchment at Savè. Precipitation provided by three regional climate models (RCMs) was analyzed. Bias in these data was first corrected using the Empirical Quantile Mapping (EQM) method be for etheir use as input to hydrological models. To achieve the objective, six hydrological models were used (AWBM, ModHyPMA, HBV, GR4J, SimHyd and Hymod). In projection, the results showed that the AWBM model appears to be the best. The multi-model approach further improves model performance, with the best obtained with combinations of the models AWBM-ModHyPMA-HBV. The AWBM model showed a fairly good capability for simulating flows in the basin with only HIRHAM5 climate model data as input. Therefore, the simulation with the HIRHAM5 data as inputs to the five (05) hydrological models, showed flows that vary at the horizons (2025, 2055 and 2085) under the scenarios (RCP4.5 and RCP8.5). Indeed, this variation is largely due to anthropogenic greenhouse gas (GHG) emissions.

Highlights

The successive reports of the Intergovernmental Panel on Climate Change (IPCC) have confirmed that major climate changes are under way and their effects are proven
Where Y is the bias corrected value of the meteorological parameter and x its value simulated by the model; FMCR is the Cumulative Distribution Functions (CDF) (Cumulative Distribution Function) of the data simulated by the MCRs and Fo−b1s is the inverse of the CDF of the observed data
In order to characterize the impacts of climate change on the availability of water resources in the Oueme catchment at Savè, the rainfall and PET resulting from the correction of the biases of the 03 investigated regional climate models (RCMs) are used as input data to 06 hydrological models (Table 1)

Summary

Introduction

The successive reports of the Intergovernmental Panel on Climate Change (IPCC) have confirmed that major climate changes are under way and their effects are proven. Due to its geographical location, West Africa will suffer more from the consequences of climate change. It is marked by the repeated drought which has worsened since the 1970s and 1980s. This vulnerability to climate disturbances is due to the diversity of impacts, multiple stresses, greater magnitude and low adaptive capacity (Obada, 2017). The study of the impacts of climate change on river flows in the Oueme catchment at Savè is of paramount importance in order to better develop adaptation policies.

Objectives

Methods

Results

Conclusion