太湖流域南宋以来旱涝规律及其成因初探

A PRELIMINARY RESEARCH ON THE REGULARITY AND FACTORS OF CHANGES OF FLOOD AND DROUGHT IN TAIHU LAKE BASIN SINCE THE SOUTHERN SONG DYNASTY

建立了太湖流域早涝等级序列,用周期分析等方法,揭示早涝变化规律。研究表明,本区的历史旱涝变化是以准100年为主要周期的复合振动,其它主要周期有准11年等。历史时期大致存在着暖湿一冷干的对应关系。在太阳活动强盛时期,一般有一个相对湿润时期。这种关系可能是太阳活动通过西太平洋副热带高压影响季风活动所致。

The grade sequence(1121-1983 AD)of flood and drought was reconstructed by means of processing information of the historic flood and drought,on the basis of systematical collection of historic climate records.It was divided into nine grades. The characteristics of the distribution both in time and space and the change regularity of flood and drought were studied through analysis of periodic change,In the meantime,the factors of flood and drought were preliminarily studied by analysing the relationships between flood/drought and cold/warm, as well as flood/drought and solar activity. The results showed that tha change of flood and drought in the Taihu Lake basin was a combined variation in which the main cycle was quasi-100 years and other cycles were quasi-11 years,Since the Southern Song Dynasty two wetter periods which lasted about 200 years respectively occurred in the 14th and 15th centuries and the 18th century.The former was wetter than the latter.Generally,during these wetter periods the winter was warmer and the solar activity was stronger.