Perfluoroalkyl substance release in permafrost surface waters is projected to increase under global warming

Abstract As the largest component of the global cryosphere, permafrost regions serve as major reservoirs for perfluoroalkyl substances. Climate change is altering cryospheric hydrological processes and pollutant transport, yet their impacts on the distribution of perfluoroalkyl substances in surface waters remain poorly understood. Here we show that intensified permafrost degradation and reduced vegetation cover substantially increase the risk of perfluoroalkyl substance contamination across global permafrost regions. By integrating environmental observations with machine learning approaches, we identify the northwestern Tibetan Plateau, Mongolia and the pan-Arctic as current contamination hotspots. Furthermore, continued deepening of the active layer under future climate scenarios increases contamination risks, particularly in a high-risk zone spanning Mongolia and northeastern China. Our findings reveal the role of climate-driven permafrost degradation in reshaping persistent pollutant distributions and provide critical insights for early warning, long-term monitoring and sustainable management of vulnerable cryospheric environments.