1
Department of Water Engineering, Razi University, Kermanshah, Iran
2
Department of Water Engineering, Faculty of Agriculture, Razi University
10.22126/atwe.2026.13579.1207
چکیده
Groundwater resources in arid and semi-arid regions play a critical role in sustaining agricultural productivity, industrial development, and domestic water supply, yet they are increasingly threatened by climate variability and anthropogenic overexploitation. This study presents a comprehensive assessment of long-term groundwater sustainability in the Kermanshah Plain through an integrated surface–subsurface hydrological modeling framework. A dynamically coupled WEAP–MODFLOW system was developed to explicitly simulate bidirectional interactions between river systems and aquifer storage under multiple climate change scenarios. The modeling framework facilitates scenario-driven simulation of CMIP5 climate projections and enables continuous monthly-scale feedback between hydrological components, including recharge, abstraction, runoff, and groundwater storage dynamics. To explicitly address climate model uncertainty, a multi-model ensemble approach based on five CMIP5 general circulation models was implemented. Historical simulations for the period 1991–2018 indicate a persistent groundwater decline of 4.3 m, corresponding to an aquifer storage reduction of approximately 253 MCM. Future projections (2018–2099) demonstrate continued depletion under all emission pathways, with relatively moderate declines under RCP2.6 (2.52 m; 251.51 MCM) and severe depletion under RCP8.5 (8.88 m; 769.04 MCM). The results further reveal strong sensitivity of groundwater dynamics to climatic forcing, particularly precipitation reduction and temperature-driven evapotranspiration increases. The proposed integrated framework provides a robust decision-support tool for evaluating climate–groundwater interactions and supports adaptive water resources planning under deep uncertainty. Overall, the findings emphasize the necessity of coupled hydroclimatic modeling approaches for improving the reliability of groundwater sustainability assessments in semi-arid environments facing intensifying climate and human pressures.
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