长沙地区暴雨气候特征分析及个例研究

Climate Characteristics Analysis and Case Study on Torrential Rain in Changsha Area

对长沙地区长沙站、宁乡站、浏阳站和马坡岭站4个站点的1981—2015年暴雨资料进行统计分析,结果表明,出现暴雨日数最多的是宁乡站,其次是马坡岭站。长沙地区春季、夏季、秋季和冬季暴雨日数分别占全年总暴雨日数的28.9%、58.5%、10.4%和2.1%。其中6月暴雨日数最多,占夏季总暴雨日数的54.1%,为全年总暴雨日数的30.9%。近35年来,长沙地区年暴雨日数呈增多趋势,气候倾向率为1.29 d/10年。春季、夏季、秋季和冬季暴雨日数整体均处于增多趋势,这与长沙近35年暴雨日数变化趋势一致,气候倾向率分别为0.83、1.07、0.17、0.08 d/10年,并以夏季增多最为明显。选取长沙市暴雨天气个例进行分析,得出暴雨主要影响系统,且水汽、动力等物理量均与暴雨有着很好的对应关系。

Statistical analysis of rainfall data of the 4 stations（Changsha Station,Ningxiang Station,Liuyang Station and Mapoling Station）in Changsha area from 1981 to 2015 was conducted. The results showed that there were the most torrential rain days in Ningxiang Station,and the least torrential rain days in Mapoling Station. The torrential rain days of spring,summer,autumn and winter in Changsha area respectively accounted for28.9%,58.5%,10.4% and 2.1% of the annual total torrential rain days. The maximum monthly torrential rain days was in June,accounting for 54.1% of the total torrential rain days in summer and 30.9% of the annual total torrential rain days. In recent 35 years,the torrential rain days in Changsha area was increasing,and the climate tendency rate was 1.29 d per 10 years. The torrential rain days in spring,summer,autumn and winter showed a increasing trend,which was consistent with the change trend of torrential rain days in recent 35 years in Changsha area,and the decadal climate tendency rates were 0.83 d,1.07 d,0.17 d and 0.08 d.The torrential rain days increased the most obviously in summer. The torrential rain weather case in Changsha City was analyzed,and the main effect system was concluded,it showed that there was fine correspondence between torrential rain and physical quantities,such as water vapor,dynamic,etc.