莱芜暴雨气候特征分析

目的]为暴雨预报提供气候背景。方法]根据莱芜市1961~2005年的历史资料,统计分析了莱芜市暴雨的年际变化、季节变化、地理分布特征,以及造成莱芜暴雨主要的天气系统和莱芜地形对暴雨形成的作用,并对2000年8月9~10日莱芜连续大暴雨过程进行了分析。结果]研究得出,莱芜暴雨主要集中出现在夏季6~8月份,尤以7月份最多;秋季暴雨是春季的2.5倍;莱芜北部和南部山区暴雨日数较多,泰莱平原入口处和东部山前平原区暴雨日数较少。结论]影响莱芜暴雨的天气系统主要是低槽冷锋,莱芜"喇叭口"型的地形有利于气流辐合加强,对暴雨形成有增幅作用。

Analysis of the Climate Characteristics of Rainstorm in Laiwu

Objective] The background for the forecast of heavy rain was provided through the research.Method] According to the historical data of Laiwu City from 1961-2005,the change of annual,seasonal rainfall and its geographic distribution of Laiwu City was statistically analyzed and the role of major weather system causing a rainstorm and Laiwu terrain causing heavy rain were also discussed.The process of continuous heavy rain from 9-10 August,2000 in Laiwu was analyzed.Results] The result showed that the rainstorm in Laiwu was mainly concentrated in the summer(from June to Aug.),especially,the maximum amount was in July;and the rainfall in autumn was 2.5 times than that in spring;the days of heavy rain in northern and southern mountain of Laiwu were many more than those in other regions.There were a small number of heavy raining days in the entrance of Taylor Plain and the plain area before eastern mountain of Laiwu.Conclusion] The heavy rain in Laiwu was mainly affected by low slot cold front of weather system;the terrain of Laiwu belonged to the "trumpet",which was conducive to strengthening convergence flow,increasing the role of rainstorm-forming.