池州市近10 a主要暴雨灾害及致灾性分析

统计2007-2016年池州市暴雨引发的主要灾害及次生灾害,运用冯利华_^1]提出的灾级概念模型对其进行分级,结果表明：2007年7月10日和2016年7月3日的暴雨灾害指数均超过了6.00,灾害等级为重灾。前者的短历时强降水特征非常明显,且由于降水发生时段主要在夜间,发生地位于山区,结果导致出现山洪、山体滑坡、泥石流等灾害；后者则是由于持续性的降水造成了城市内涝、多条河流超警戒水位甚至发生溃堤。文章还基于上述原因从致灾因子和承灾体即短时强降水和地形因素两方面重点分析其致灾性,结果表明：凌晨5时前后是池州市暴雨灾害的最强致灾时段,这主要是因为此时段为短时强降水高发时段,一旦发生持续性短时强降水将会造成严重的暴雨灾害；而在空间上池州市东至县、贵池南部山区及九华山区域为暴雨灾害高发区域,其原因是东至县为喇叭口特殊地形,而其他地区多为山区,同时由于池州市位于副高西北侧,汛期西南气流输送比较强盛,通过山区地形的强迫抬升和动力抬升作用容易触发对流,产生强降水过程,造成暴雨灾害。

Analysis of major rainstorm disasters and their disaster causing in Chizhou City in recent 10 years

Based on the statistics of the major and secondary disasters caused by the rainstorm in Chizhou City from 2007 to 2016, this paper classifies them by using the concept model of disaster level proposed by Feng Lihua _^1]. The results show that the rainstorm disaster indexes of July 10, 2007 and July 3, 2016 are over 6.00, and the disaster level is serious. The former is characterized by short duration and strong precipitation, which occurs mainly at night in mountainous areas, resulting in mountain floods, landslides, mudslides and other disasters; the latter is caused by continuous precipitation, which leads to urban waterlogging, many rivers exceeding the warning water level and even dam break. Based on the above reasons, the paper analyzes the disaster causing factors and the disaster bearing body, i.e. short-term heavy rainfall and topographic factors. The results show that the time variation characteristics of short-term heavy rainfall in Chizhou City in recent 10 years are mainly manifested as the strongest disaster causing period around 5:00 a Most of the mountainous areas in the south of Guichi and Jiuhua Mountain area are mainly due to the fact that Chizhou City is located in the north-west side of the deputy high, and the southwest air flow is relatively strong during the flood season, which is prone to heavy precipitation. At the same time, the air block is easily lifted under the effect of solar radiation in the afternoon of the flood season, which triggers convection, causing rainstorm; in addition, it is also due to the dynamic forced lifting of the mountain area and the special topography of the trumpet mouth of the county in the East There is a close relationship.