Variations of rapidly intensifying tropical cyclones and their landfalls in the Western North Pacific

ABSTRACT

Rapid intensification (RI) plays a crucial role in intensifying tropical cyclones (TCs) within the context of climate change. This study investigates variations of RI TCs and their cyclonic energy upon landfall in the western North Pacific (WNP) during 1986–2017. Statistically, 31.2% of 946 historical TCs underwent RI events (RI TCs) and made 341 landfalls. The numbers of landfalling RI TCs show a significant increasing trend with strengthened high-intensity TCs. Both the lifetime maximum intensity (LMI) and landfalling cyclone energy of TCs that did not undergo RI exhibit decreasing trends. The mean genesis and on-set locations of RI TCs indicate northwestward migration. Cyclone energy from landfalling RI TCs has increasing trend along the coasts of southern China and Japan, while that along the Philippine coasts tend to exhibit an opposite trend. We attribute such trends to the poleward migration of the mean latitude of LMI. With increasing sea surface temperatures, relative high tropical cyclone heat potential provided by poleward-extended warmer mixed layer in warm seasons may play an important role in favoring RI events. Moreover, increases of 200–850 hPa vertical wind shear in the eastern WNP is likely to attribute to the westward migration of RI activities.

KEYWORDS:

• Rapid intensification
• western North Pacific
• lifetime maximum intensity
• landfalling cyclone energy
• large-scale environment

Data availability

The version v04r00 of IBTrACS dataset was retrieved via https://www.ncdc.noaa.gov/ibtracs/index.php?name=ib-v4-access in March 2019. The ERSST v5 dataset is available at https://www.esrl.noaa.gov/psd/data/gridded/data.noaa.ersst.v5.html. The SODA3 dataset is accessible from https://www2.atmos.umd.edu/~ocean/. The NCEP-NCAR reanalysis dataset is provided by the NOAA/OAR/ESRL PSL, Boulder, Colorado, USA, from their website at https://psl.noaa.gov/data/gridded/data.ncep.reanalysis.html.

Disclosure statement

No potential conflict of interest was reported by the authors.

Additional information

Funding

This research is supported by the National Key Research and Development Program of China (Grant No. 2018YFC0407506) and National Natural Science Foundation of China (Grant No. 42076233).