![]() Additionally, we show that climate-modulated changes in hurricane tracks16,17 contribute to the increasingly slow decay. This stored moisture constitutes a source of heat that is not considered in theoretical models of decay13–15. We also show, using computational simulations, that warmer sea surface temperatures induce a slower decay by increasing the stock of moisture that a hurricane carries as it hits land. Thus, whereas in the late 1960s a typical hurricane lost about 75 per cent of its intensity in the first day past landfall, now the corresponding decay is only about 50 per cent. Here we analyse intensity data for North Atlantic landfalling hurricanes¹¹ over the past 50 years and show that hurricane decay has slowed, and that the slowdown in the decay over time is in direct proportion to a contemporaneous rise in the sea surface temperature¹². In contrast to the effect of a warming climate on hurricane intensification, many aspects of which are fairly well understood6–10, little is known of its effect on hurricane decay. This is because hurricanes are fuelled by moisture from the ocean1–3, and so hurricane intensity decays rapidly after striking land4,5. When a hurricane strikes land, the destruction of property and the environment and the loss of life are largely confined to a narrow coastal area. Each marker locates the centroid position (the mean of hurricane positions at four synoptic times past landfall) of an event, with its size proportional to the corresponding τ. d, Spatial distributions and proportions of landfalling track modes over 1967–19–2018. c, Mean τ (dots with 95% confidence intervals) and number of landfall events (bars) in different landfalling track modes over 1967–19–2018. ![]() Effective 200-km radii of moisture supply from the hurricane centres past the first day of landfall are depicted. Best tracks of Hurricanes Juan (1985), Dolly (1996), Hermine (2016) and Irma (2017) are shown at six-hourly intervals. ![]() b, Examples of different landfalling track modes. Four outliers, Hurricanes Juan (1985), Paloma (2008), Isaac (2012) and Hermine (2016), are specified. Linear regression line (solid line) and its corresponding 95% prediction band (dashed lines) are provided. Four hurricanes that underwent different landfalling track modes are emphasized and shown in b. Landfalling hurricane track modes and decayĪ, Scatter plot of τ (derived from 0.2° resolution) versus Ao with landfalling track modes indicated.
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