基于历史文献记载的关中地区中世纪干旱过程

基于关中地区公元900-1199年的历史文献资料,采用旱涝等级和比值法对关中地区中世纪的降水变化进行了分析。研究结果表明:在400年间,不同程度的干旱事件共发生169次,占总年数的42.25%,水涝事件发生83次,占总年数的20.75%,干旱是该时期气候的大背景。除此之外,作者还对研究区公元800-1199年的旱涝等级序列进行线性拟合和10年滑动平均分析,结果表明本区的干旱化过程自10世纪初开始,而公元856年为湿润期向干旱期的转折点。这次干旱过程也得到了来自黄土地层记录和其他研究的支持。

A drought process of medieval times in Guanzhong region based on historical records

Using the evaluation method of drought/flood grade,we analyzed the precipitation change between 900-1199 A.D.in Guanzhong region based on the historical literature.The results indicated that the different degrees of droughts happened 169 times,taking 42.25% of total years,and the floods happened 83 times,taking 20.75% of total years.Drought dominated the climate change of the period.From the drought and flood grade sequence of linear fitting and 10-year running mean,we can find that a gradual process of climatic drought was showed since the beginning of 10-th century.856 A.D.was the turning point from wet period to dry period.The drought process was also obtained support from loess record and other research.