From London, at the Environmental Catastrophes and Recovery in the Holocene conference
Historical records compiled by local governments along China's southeastern coast during the past 1,000 years suggest that there's a regular cycle in the annual number of typhoons that strike the area.
Officials in many counties in China record events of importance in semiofficial local gazettes, or fang zhi, says Kam-biu Liu, a geographer at Louisiana State University in Baton Rouge. Because gazetteers as long ago as the fifth century A.D. discriminated between typhoons and other types of storms, these archives provide a wealth of information about long-term variations in the frequency of typhoons that hit a particular area.
The documents compiled in southeastern China's Guangdong province show that since A.D. 975, at least 571 typhoons have hit land there, says Liu. Although the fang zhi probably don't record all the typhoons that struck during that period, the instru