Reconceptualizing global groundwater risk beyond stress metrics

Groundwater, Earth’s largest source of liquid freshwater, sustains ecosystems and provides freshwater supply for billions of people worldwide. Increasing reliance on groundwater resources, together with climate-driven changes in recharge, places growing pressure on aquifers, contributing to depletion and threatening both ecosystem integrity and socio-economic stability. Global assessments of groundwater stress remain largely based on hydroclimatic indicators, offering limited insight into how physical pressures translate into societal consequences, or why similar levels of groundwater stress can lead to markedly different outcomes across regions. Here, we advance a global approach to groundwater risk assessment that moves beyond stress metrics by jointly considering physical groundwater pressures, the presence of human populations and groundwater-dependent assets, and the societal capacity to cope with and respond to stress. Applied globally at high spatial resolution for the early 21st century, this approach enables a systematic exploration of how spatial patterns of groundwater risk evolves when societal conditions are explicitly taken into account. Rather than focusing on single indicators, the analysis highlights pronounced spatial heterogeneity in risk patterns and demonstrates how societal conditions can amplify or dampen the severity of groundwater-related impacts, even under comparable levels of physical stress. We will identify regions where groundwater risk is most sensitive to changes in societal capacity, as well as priority areas where targeted investments in governance, infrastructure, and social resilience could most effectively reduce future groundwater risk under rising water demand and climate change.