基于聚类分析的短历时暴雨雨型研究

Research on Rainstorm Pattern of Short Duration Based on Cluster Analysis

暴雨雨型直接影响着洪峰流量的大小及洪水过程,研究暴雨雨型可为防洪排涝、山洪灾害防治提供科学依据。根据陕西省宝鸡气象站1981~2017年自记降雨资料,采用Ward聚类分析法对120场暴雨做了分类研究,从多角度分析了雨型的发生规律,初步探讨了雨型与山洪内涝的关系。结果表明,聚类分析法在雨型分类中具有较好的适用性;宝鸡气象站120场暴雨分为5种类型,分别为单峰靠前的Ⅰ型,雨峰位于第一时段且中间雨量少的Ⅱ型,近乎均匀分配、中部略高的Ⅲ型,雨峰位于最后一时段且中间雨量少的Ⅳ型及单峰靠后的Ⅴ型;场次暴雨雨型以Ⅰ、Ⅲ型为主,不同历时Ⅰ、Ⅲ型暴雨出现的场次相当,Ⅱ、Ⅳ、Ⅴ型随着场次暴雨历时的增加发生几率减小;独立短历时场次暴雨中Ⅰ、Ⅲ型更易引发山洪内涝。

The rainstorm types directly affect the size of the flood peak flow and the flood process.The study of the rainstorm types can provide a scientific basis for flood prevention and drainage,and prevention of mountain flood disasters.Based on the self-recorded rainfall data from 1981-2017 in Baoji Meteorological Station of Shaanxi Province,the paper selected 120 storms and used the Ward cluster analysis method to classify them.The occurrence patterns of rain patterns were analyzed from different aspects,and the relationship between rain pattern and torrent and waterlogging was preliminarily discussed.The results show that the cluster analysis method has good applicability in the rain classification;The 120 storms at Baoji Meteorological Station are divided into five types.Firstly,typeⅠ with a single peak at the top,and the typeⅡis that the rain peak is located in the first period and the middle rainfall is less.While the typeⅢ with almost uniform distribution and slightly higher in the middle.In the meanwhile,typeⅣ with rain peaks in the last period and less rainfall in the middle and TypeⅤ with a single peak behind;TypesⅠandⅢare the main types of heavy rainstorms.The occurrence of rainstorms of typeⅠand typeⅢwith different time but are similar,and typeⅡ,ⅣandⅤdecrease the probability that the increase of the time duration of rainstorms.TypeⅠ and typeⅢ are more likely to cause torrent and waterlogging in independent short-duration storms.