Decoupling Between Heavy Precipitation Expansion and Population Exposure in a Warming World

Abstract Climate change is intensifying the global water cycle, amplifying heavy precipitation and associated flood risks. However, the spatial extent of heavy precipitation—a critical factor for assessing total societal impact—has been largely overlooked. Here, we develop a method to identify the spatial extent of heavy precipitation that incorporates both intensity and anisotropy. Using multisource observations (ERA5, GPM, TRMM) and 23 CMIP6 model projections, we then quantify future changes in heavy precipitation extent and examine how these changes interact with population redistribution under different Shared Socioeconomic Pathways (SSPs). The results reveal that global daily heavy precipitation (≥50 mm/day) expands 2.86 times faster under the SSP5‐8.5 scenarios than the SSP2‐4.5 scenarios. Hotspots intensify in populous eastern North America, South Asia, central Africa, and northern Oceania. Conversely, population exposure surges 4.0 times faster under SSP2‐4.5 versus SSP5‐8.5. Meanwhile, regional disparities intensify. Exposure declines in Asia and South America, despite expanding precipitation, while North America, Africa, Europe, and Oceania face escalating risk. The exposure changes are primarily attributable to population redistribution under SSPs, not heavy precipitation expansion. This spatial mismatch between hazard development and demographic trends challenges hazard‐centric risk paradigms and redefines climate adaptation priorities. Our findings offer a new perspective for the global response to climate change. Spatial coupling between precipitation systems and human settlements—not just temporal hazard intensity—determines future disasters.