Human-caused ocean warming has intensified recent hurricanes

Abstract Understanding how rising global air and sea surface temperatures (SSTs) influence tropical cyclone intensities is crucial for assessing current and future storm risks. Using observations, climate models, and potential intensity theory, this study introduces a novel rapid attribution framework that quantifies the impact of historically-warming North Atlantic SSTs on observed hurricane maximum wind speeds. The attribution framework employs a storyline attribution approach exploring a comprehensive set of counterfactuals scenarios—estimates characterizing historical SST shifts due to human-caused climate change—and considering atmospheric variability. These counterfactual scenarios affect the quantification and significance of attributable changes in hurricane potential and observed actual intensities since pre-industrial. A summary of attributable influences on hurricanes during five recent North Atlantic hurricane seasons (2019–2023) and a case study of Hurricane Ian (2022) reveal that human-driven SST shifts have already driven robust changes in 84% of recent observed hurricane intensities. Hurricanes during the 2019–2023 seasons were 8.3 m s −1 faster, on average, than they would have been in a world without climate change. The attribution framework’s design and application, highlight the potential for this framework to support climate communication.