Tracks of tropical cyclones in Northwestern Pacific Ocean correspond to the ITCZ shifts and NAO phase over the past 2ka.

Abstract

The northwestern Pacific Ocean and south China sea are where tropical cyclones occurmost frequently. This study collected data of paleotyphoons found in China’s officialhistorical records over the past two thousand years with known typhoon activity reports. Thecollected data is then subjected to statistical analyses focusing on typhoon activity in coastalregions of southeastern China to garner a better understanding of the long-term evolution ofmoving paths and occurrence frequency, especially those typhoons making landfall inmainland China. We analyzed the data with the year and month of each typhoon event, aswell as the number of events in a ten-year period. The result shows that (1) the tracks oftyphoon correspond to the north/southward migration of the ITCZ and phase of NAO, whichshows a nearly 30-yr and a 60-yr cycle during the LIA. (2) paleotyphoons made landfall inmainland China one month earlier during MWP than those during LIA. According topaleotyphoon records over the last two thousand years, typhoons made landfall insoutheastern China frequently around 490-510 A.D., 700-850 A.D., and after 1500 A.D. Thenumber of typhoons striking Guangdong Province peaked during the coldest period in 1660-1680 A.D.; however, after 1700 A.D., landfall has migrated farther north