华南暖区暴雨事件的筛选与分类研究

Selection and Classification of Warm-Sector Heavy Rainfall Events over South China

利用逐小时降水资料,采用客观方法对1982～2015年华南地区暖区暴雨进行了筛选和分类研究。主要结果如下:华南区域暖区暴雨事件共计177例,暖区暴雨占筛选的暴雨事件的16.86%,表明暖区暴雨是华南非常重要的降水过程。暖区暴雨主要出现在4～7月,6月份最多,平均持续11.58 h。暖区暴雨事件发生位置主要集中在广东、广西的沿海地区和粤北山区,有四个降雨中心。产生华南暖区暴雨的天气形势主要有四类,切变线型、低涡型、南风型和回流型,不同类型的暖区暴雨对华南地区的内陆和沿海的作用不同,且南风影响下的暖区暴雨发生频率较高,影响较大,是一类较为重要的暖区暴雨。

Based on hourly precipitation data, warm-sector heavy rainfall events are selected and classified using an objective method over South China during 1982–2015. The main results are as follows. There are a total of 177 warm-sector heavy rainfall events in South China during the study period. Warm-sector heavy rainfall events account for 16.86% of the selected severe heavy rainfall events, indicating that the warm-sector rainfall is a very important precipitation process in South China. Most of warm-sector rainfall events occur from April to July, and a majority occurs in June. The average duration of all events is 11.58 h. There are four centers of warm-sector rainfall events, which are mainly concentrated in the coastal regions of Guangdong, Guangxi, and the northern mountainous areas of Guangdong Province. According to theweather systems that affect rainfall events, the selected warm-sector rainfall events are divided into four types, i.e., shear line, vortex, southerly wind, and backflow. The result shows that different types of warm-sector rainfall events have different effects on the inland and coastal areas of South China, and the occurrence frequency of southerly wind type event is the highest among the four types. Generally, the southerly wind type is an important type of warm-sector rainfall.