Assessment of the relative impacts of climate changes and anthropogenic forcing on Ouergha watershed hydrology (North-East of Morocco)

Abstract

Understanding the spatiotemporal distribution of past and future climate change impact is essential for effective water resource management. This study aims to reveal the impact of temperature and precipitation change on hydrological streamflow of Ouergha watershed and on the inflow regime of Al Wahda dam. Initially, historical climate trend was assessed using Mann Kendall tests and Sen’s slope. Then, regional Climate Models (Cordex-Africa) were used to project future precipitation and temperature data under two emission scenarios (RCP4.5 as realistic and RCP8.5 as pessimistic). After correcting the biases in climatic variables using three different methods, the calibrated and validated SWAT model was forced to project the hydrological simulations under both scenarios. The study shows a clear decreasing in precipitation and augmentation in annual mean temperature over the past decades. In addition, projected climate variables expected severe change in future precipitation (decreasing) and mean temperature (Increasing). The impact of this climatic alteration is expected to extremely affect rivers discharge and reservoir inflows in both magnitude and timing.

The Application of SWAT Model and Remotely Sensed Products to Characterize the Dynamic of Streamflow and Snow in a Mountainous Watershed in the High Atlas

“…For instance, Ref. [ 16 , 17 , 18 , 19 , 20 ] employed the SWAT model to simulate basin hydrology in a variety of tropical basins in Morocco and was able to demonstrate its flexibility, consistency, and applicability as a hydrological model for the planning and management of water resources. However, the majority of SWAT implementations in Morocco concentrated on low-altitude basins unaffected by snow.…”