Recent Increase in Tropical Cyclone Weakening Rates Over the Western North Pacific

This study investigates annual mean changes in 24‐h weakening rates of western North Pacific tropical cyclones (TCs) and annual number of rapid weakening (RW) events from 1982 to 2019. There is a significant increasing trend in the mean weakening rate, which correlates with a significant increase in RW number. Because stronger TCs are more likely to experience greater weakening rates and thus undergo RW, the increase in the ratio of intense TCs to all TCs can cause an increase in the weakening rate and RW frequency. Furthermore, the weakening rate and the RW number significantly increase over the region of 25°N–35°N, 120°E–150°E from 1982–2000 to 2001–2019. Over this region, there are stronger sea surface temperature gradients in more recent years, likely contributing to a higher probability of TCs undergoing RW. Other environmental variables do not exhibit significant changes. Our study highlights inhomogeneous Pacific warming that may favor RW of TCs.