基于copula联合分布的大连市极端降水特征分析

Analysis of extreme precipitation of Dalian city based on the Copula function

利用大连市1960-2015年逐日降水量数据,采用百分位法确定极端降水阈值,分析各极端降水要素随时间的变化,并得到适合各要素边缘分布函数。构建Copula函数联合各极端降水要素,分析要素间内在联系。结果表明极端降水量和贡献率关系密切,将二者联合进行分析可以更好地反应大连市极端降水特征。

To analyze the every extreme precipitation elements time-varying including amount, intensity, days happened and rate of the contribution of City Dalian, we use the statistic derived from the every days observation of the precipitation in Dalian meteorological station aged from 1960-2013, and the method of ensuring its range this article use is percentile, then we can construct every marginal distribution function. After that the Copula function is founded for contacting every elements. Results show that： the relation between extreme precipitation and the rate of contribution is a significant positive correlation.o