Climate Change Impact on Future Flows in Semi-arid Environment, Case of Essaouira Basin (Morocco)

Abstract

The objective of this study was to simulate future flows in Essaouira basin (Morocco) by 2050, using the two-variable Rural Engineering model at the monthly time step (GR2M). The quality criteria revealed very interesting values obtained from the model on the Igrounzar and Zelten stations of the Essaouira basin with Nash higher than 70% and R2 higher than 0.70. The results obtained by the GR2M model under Representative Concentration Pathway (RCP) 2.6 and 8.5 scenarios of the fifth phase of the Coupled Model Intercomparison Project (CMIP5) predict that future flows will show an upward trend of 19 and 43%, respectively. However, under the RCP 4.5 scenario, future flows show a downward trend of 38%. Nevertheless, planning for future uses of water resources in the Essaouira basin should take this situation into account.