Historical and future water quality risks driven by climate change: Strategic management and overcoming challenges

Climate change affects water quality by increasing land and water temperatures and intensifying extreme weather events. Using over 2.2 million water quality measurements and up to 50 years of temperature records (1973-2023), this study evaluates climate-driven water quality risks. Significant warming trends (+0.35 °C decade^-1 for land surface; +0.30 °C decade^-1 for surface water) were observed, with heightened seasonal vulnerabilities during spring and summer. Direct effects, such as dissolved oxygen depletion and altered nutrient dynamics, contribute to immediate challenges, while long-term effects drive algal blooms, microbial contamination, and ecosystem instability. Future projections (∼2100) under Representative Concentration Pathways (RCP) reveal that stringent mitigation (RCP 2.6) preserves water quality, whereas RCP 8.5 results in severe hypoxia, eutrophication, and biodiversity loss, preventing resilience. Based on these findings, adaptive strategies, including mitigation, nutrient control, and ecosystem-based approaches, were proposed to enhance the resilience of aquatic ecosystems and inform global strategies to address climate-driven water quality challenges.