Water stress evolution and redistribution pathways under global inequality in consumption

. Under the medium scenario, >53 % of the global population, mainly in low-income countries across Asia and Africa, will face high water stress. Based on the weighted transfer contribution ratio (WTCR) and the consumption-based water stress index (CWSI) dual indicator framework, this study comprehensively identifies future water risk and redistribution potential. Results show that although surplus water from redistributive contributing zones may be sufficient to offset shortages in systemic collapse zones before 2070, redistribution capacity declines significantly by 2090, threatening the structural stability of the global water security system. Effective global water governance must therefore promote equitable burden sharing and trade restructuring. In particular, high-income countries should assume greater environmental responsibility to support the integrated achievement of the Sustainable Development Goals (SDGs).