China’s historical record in the search of tropical cyclones corresponding to ITCZ shifts over the past 2ka

Abstract

The northwestern Pacific Ocean and south China sea are where tropical cyclones occur most frequently. Many climatologists also study the formation of Pacific Ocean warm pools and typhoons in this region. This study collected data of paleotyphoons found in China’s official historical records over the past two thousand years with known typhoon activity reports. The collected data is then subjected to statistical analyses focusing on typhoon activity in coastal regions of southeastern China to garner a better understanding of the long-term evolution of moving paths and occurrence frequency, especially those typhoons making landfall in mainland China. We analyses the data with the year and month of each typhoon event, as well as the number of events in a ten-year period. The result shows that (1) north/southward migration of typhoon paths correspond to the north/southward migration of the Intertropical Convergence Zone (ITCZ) during Medieval Warm Period (MWP) and Little Ice Age (LIA), (2) paleotyphoons made landfall in mainland China one month earlier during MWP than those during LIA. This implies a northward shift in ITCZ during MWP. Typhoons tend to make landfall in Japan during El Nino-like periods and strike the southern coastal regions of China during La Nina-like stages. According to paleotyphoon records over the last two thousand years, typhoons made landfall in southeastern China frequently around 490–510 A.D., 700–850 A.D., and after 1500 A.D. The number 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.