Extreme Dry-Hot in North America and Europe: The Amplified Role of Warming-Enhanced Land-Air Coupling

Abstract Greenhouse gases (GHGs) drive global land warming with varying regional impacts, but the role of land-atmosphere interactions in amplifying future warming hotspots remains underexplored. Our study shows that, under uncontrolled GHG emissions, North America and Europe are projected to experience the highest warming by the late 21st century (3.7°±0.7°C and 3.8°±0.5°C, respectively), exceeding the global average of 2.7°±0.4°C in other regions. Approximately one-quarter of this warming in North America and Europe is linked to land-air coupling and associated hot-dry feedback mechanisms, where warming accelerates soil drying, further intensifying surface heating. This feedback could transform nearly 30% of land in these regions into arid or extremely arid zones, significantly impacting ecosystems and agriculture. These results underscore the vulnerability of North America and Europe to amplified climate risks driven by GHG emissions and strengthened land-atmosphere feedbacks.