In China, the abundance of historical documentary records in the form of Fang Zhi (semiofficial local gazettes) offers an extraordinary opportunity for providing a high-resolution historical dataset for the frequency of typhoon strikes. We have reconstructed a 1,000-year time series of typhoon landfalls in the Guangdong Province of southern China since AD 975 based on data compiled from Fang Zhi. Even though the 571 typhoon strikes recorded in the historical documents probably underrepresent the total number of typhoon landfalls in Guangdong, calibration of the historical data against the observations during the instrumental period 1884-1909 suggests that the trends of the two datasets are significantly correlated ( r ϭ 0.71), confirming that the time series reconstructed from historical documentary evidence contains a reliable record of variability in typhoon landfalls. On a decadal timescale, the twentyyear interval from AD 1660 to 1680 is the most active period on record, with twenty-eight to thirty-seven typhoon landfalls per decade. The variability in typhoon landfalls in Guangdong mimics that observed in other paleoclimatic proxies (e.g., tree rings, ice cores) from China and the northern hemisphere. Remarkably, the two periods of most frequent typhoon strikes in Guangdong (AD 1660 -1680, 1850-1880) coincide with two of the coldest and driest periods in northern and central China during the Little Ice Age. Conceivably, the predominant storm tracks shifted to the south during these cold periods, resulting in fewer landfalls in Japan and the east-central Chinese coast but more typhoons hitting Guangdong. Spectral analysis of the Guangdong time series reveals an approximately fiftyyear cycle in typhoon landfall frequency. While the physical mechanism remains to be identified, it is tempting to relate this periodicity to the pentadecadal variability identified in the North Pacific Index (NPI) time series.

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The interannual variability in typhoon landfalls over China is investigated using historical and modern records. For the purpose of substantiating and elaborating upon the claim of north to south variation in tropical cyclone activity over China, a north-to-south anti-correlation in yearly activity is confirmed in the historical cyclone records. When cyclone activity over the province of Guangdong is high (low), it tends to be low (high) over the province of Fujian. A similar spatial variation is identified in the modern records using a factor analysis model, which delineates typhoon activity over the southern provinces of Guangdong and Hainan from the activity over the northern provinces of Fujian, Taiwan, Zhejiang, Shanghai, Jiangsu, and Shandong. A landfall index of typhoon activity representing the degree to which each year follows this pattern of activity is used to identify correlated climate variables. A useful statistical regression model that includes sea-level pressure differences between Mongolia and western China and sea-surface temperature (SST) over the northwestern Pacific Ocean during the summer explains 26% of the interannual variability of the landfall index. It is suggested that a stronger than normal north-south pressure gradient increases the surface easterly wind flow over northern China; this, coupled with lower SST over the Pacific, favors typhoons taking a more westerly track toward southern China.

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