钱塘江河口涌潮强弱的历史变迁(1471-2001)

整理《中国近五百年旱涝分布图集》及其"续编""再续编"中1471-2000年间浙江金华与安徽屯溪两个站点的旱涝指数,将其作为反映钱塘江年径流量波动的指标,根据1950-2000年实测的钱塘江径流大小与海宁盐官站潮差和涌潮大小的相关关系,推断出五百余年来钱塘江涌潮强度变迁趋势。经检验,钱塘江流域旱涝指数特征与史料所载涌潮异常年份相符,且指数序列与同时期海宁盐官历年最大潮差值序列之间的相关系数具有较强相关性。将现代实测盐官历年最大潮差与旱涝指数拟合,得到函数关系式为y=-7.2x2+40.3x+580.1(其中x为旱涝指数,y为盐官年最大潮差)。又根据盐官潮差与涌潮高度间函数关系推出了明中期以后盐官历年涌潮最大强度,并绘制了1471-2001年间的钱塘江涌潮强弱变化曲线图。

The Historical Change of the Strength of Tidal Bore in Qiantang River Estuary from 1471 to 2001 AD

In this paper, the dry and wet data of Jinhua in Zhejiang province and Tunxi in Anhui province in The Atlas of Drought and Flood Distribution in China in Recent Five Hundred Years(中国近五百年来旱涝分布图集)were extracted and used to reflect the dry and wet situation of the Qiantang river basin. According to the science on modern tidal bore, the dry and wet condition of the Qiantang river basin is significantly correlated with the strength of tidal bore. When we verify the relationship between the dry and wet data of the Qiantang river basin and the strength of tidal bore through historical documents and modern data,we construct the correlation function between them. Let Y be the maximum tidal range of Yanguan in Haining, Which represents the strength of tidal bore, and X be the degree of wetness and dryness, then the function between them is going to be y=-7.2 x2 + 40.3 x + 580.1. Through this formula, this paper restores the change of the strength of the Qiantang river tidal bore from 1471 to 2001 AD.