Rising coastal wave hazards from climate-driven winds and tropical cyclones.

Coastal wave storms are intense, long-lasting hazards that threaten populated shorelines worldwide. Under global warming, large-scale wind patterns are changing and modifying ocean surface waves. However, the long-term evolution of coastal wave storms and the drivers of their change remain poorly quantified on global scales. Here, using global wave simulations with corrected tropical-cyclone winds for 1990-2023, we show that coastal wave storm frequency increases worldwide, with the strongest rise along the Atlantic coasts (∼5% per decade). This basin-wide enhancement is primarily driven by intensified nearshore winds, while tropical cyclones act as an additional amplifier. Combining changes in frequency, duration and intensity, we identify the Yellow Sea-East China Sea and the Northwest Atlantic coasts as emerging hotspots of rapidly intensifying wave hazards. Our findings provide the first global-scale baseline for attributing coastal wave-storm trends to changes in the wind-storm environment, thereby informing early-warning systems and guiding adaptation strategies under continued climate change.