Assessment of climate change impact on surface water resources in the Mitidja plain, Algeria

The scarcity of surface water resources has a significant impact on Mediterranean basin. This study aims to assess the climate change impacts on surface water resources in the Mitidja plain in Algeria. Two pre-calibrated monthly water balance models, namely, the GR2M model and the abcd model, were used. These models were driven by bias-corrected datasets from the fifth and sixth phases of the Coupled Model Intercomparison Project (CMIP5 and CMIP6) under two Representative Concentration Pathway scenarios (RCP4.5 and RCP8.5) and two Shared Socioeconomic Pathways (SSP2 and SSP5). The combined Box–Cox transformation and bootstrapping procedure was used to aggregate the multiple runoff projections generated. The results revealed significant variations in the runoff patterns across the different sub-basins. In addition, all scenarios indicated a reduction in projected runoff across all sub-basins of the Mitidja plain, spanning from 26 to 74.32%. Furthermore, CMIP6 simulations showed more intense changes over the Mitidja basin.