The duration (Td) of typhoon along the costal areas in Jiangsu, Zhejiang and Shanghai during period of the Qing Dynasty and the Republic of China (1644-1911 A. D) is reconstructed based on the historical documentaries and judgment of typhoon events. The results show that the average value of Td is 2 days/year. Td has increased since the mid 19th century, which indicates that typhoon is getting active. The wavelet analysis shows 4 ～ 8 years and 6 ～ 8 years quasi-periods in Td variation respectively in the 1640 ～ 1690s and 1800 ～ 1830s.The periodicity in other periods is not obvious. Non-correlation of MTC with ATC in annual and decadal relation may be the important reason of no evident law of Td distribution. Typhoon duration does not entirely correspond with global temperature change. The study shows that only warming in the early 17th century is basically consistent in time with amplification of Td value%根据清代-民国的历史文献,在判定台风现象记录的基础上,建立了1644-1911年苏、沪、浙沿海受台风影响的天数Td序列,显示研究区在此期间内年均有2 d左右受台风影响;19世纪中期之后,台风影响时间有所延长,指征了该地台风活动趋于活跃的现象.小波分析显示1640-1690年代和1800-1830年代,Td变化分别存在4～8 a和6～8 a的准周期现象,但其他时段周期性规律很不显著.MTC与ATC之间缺乏年际和年代际的对应关系可能是导致本研究Td分布无明显规律的重要原因.台风影响陆地时间与全球冷暖变化并不完全对应,仅发现17世纪早期的增暖与Td值放大在时间上基本一致.
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