庐山台风暴雨天气系统配置与云型分析

Analyses on weather system configuration of typhoon rainstorm and cloud type in Lushan

使用近10a以来登陆台风对庐山暴雨影响的历史资料进行分析,结果表明:(1)影响庐山的台风移动路径主要为中路,细分为中路Ⅰ型和中路Ⅱ型,其中对庐山影响最大的是中路Ⅰ型,其它登陆台风,中心位置<25°N或>30°N,对庐山的影响都很小。(2)中、低层以及地面合成场存在一定的共性,即(32～42°N,100～110°E)一带形成高压阻挡坝,长江以南地区、南海以及台湾处于闭合低压区内。这种配置是庐山台风暴雨常见的天气系统配置类型。(3)庐山地形对台风降水的增幅作用十分明显。(4)庐山台风暴雨主要有3种云型:①台风外围环流云型;②台风螺旋雨带云型;③台风低压(槽)云型。这3种云型表明了台风3个不同阶段的特征,庐山台风暴雨主要与西风带系统和副热带高压阻隔作用、涡旋Rossby波激发的螺旋雨带、中尺度对流云团发展以及低层西南暖湿低空急流等因素有关。

Historical data of Lushan precipitation due to the landed typhoon in the last 10 years are analyzed,the results are as follows.（1） The typhoon moving paths impacting on the Lushan can be divided into Middle RoadⅠ and Ⅱ types,the former influences are the greatest,other landed typhoons whose central location is less than 25 °N or greater than 30 °N have very small effects on the Lushan.（2） There are a number of common features in the mid-,lower-and ground synthetic field,namely,high pressure extends westward to an area（32-42 °N,100-110 °E） and forms the high-pressure blocking dam,the south area of the Yangtze River,the South China Sea and Taiwan are in a closed low pressure region,which is a common type of weather system configuration in the course of Lushan typhoon storms.（3） The precipitation increase due to impact of Lushan terrain on typhoons is very obvious.（4） Typhoon rains in Lushan belong to three cloud types,including ①circular cloud type of peripheral typhoon,②cloud type of typhoon spiral rainbelt,③typhoon low pressure（trough） type.The cloud types are caused in three different typhoon stages,the typhoon rainstorms are related with the westerly system and the subtropical high barriers,the spiral rainbelt is triggered by vortex Rossby wave,mesoscale convective cloud development and the warm and moist low-level southwest jet and other factors.