北京短历时强降雨的时空分布

Spatial and Temporal Distribution of Short-Lasting Heavy Rainfall in Beijing

利用北京地区157个人工站和自动站观测资料,对北京地区短历时强降雨的时间、空间分布特征以及与年总降水量的关系进行分析,结果表明:12007—2012年,短历时强降雨的次数大体呈现递增趋势,但各年发生的次数差异较大;2从时空分布特征来看,短历时强降雨最易发生在7月,时段集中在傍晚前后和凌晨,而发生地点集中在北京西山前的平原地区包括昌平中部东部、顺义西部、石景山区、丰台区西部、房山东部南部;3从短历时强降雨与年降水量的关系来看,短历时强降雨发生次数多的年份降水量也高,短历时强降雨对于年降水量的贡献较大。

Using the data from 157 manual observation stations and AWS＇s,the spatial and temporal characteristics of the short-lasting heavy rainfall in Beijing are analyzed.The results show that：（1）The number of short-lasting heavy rainfall events increased generally from 2007 to 2012.There are large differences among years.（2）From the spatial and temporal characteristics,it is found that the shortlasting heavy rainfall occurred more frequently in July,evening and early morning,in the plain area in front of the Xishan mountain,including the central and east parts of Changping,the western Shunyi,Shijingsha,western Fengtai,and southeastern Fangshan districts.（3）The relationship between shortlasting heavy rainfall and annual total rainfall is examined,and it is found that the annual total rainfall was larger in the year with more short-lasting heavy rainfall events,and the short-lasting heavy rainfall made an important contribution to annual total rainfall.