一次冷锋后飑线的大振幅重力波特性分析

本文用较密集的观测资料分析江淮地区一次冷锋后的飑线过程。分析表明飑线的生成和发展与中尺度冷涌活动有关，它具有大振幅重力波的特征。重力波在传播过程中于大别山东侧形成边缘锋，边缘锋的传播更类似于沿岸Kelvin波，大振幅重力波在边界层特征更明显。这类被地形拦截的大振幅重力波是江淮地区冷锋后飑线的一种可能激发机制。

Characteristics of Large Amplitude Gravity Wave of Squall Line Behind the Cold Front

In this paper, a squall process occurring behind the cold front in Chang Jiang—Huai He area is analysed with the help of the enhanced observational data. The analysis shows the genesis and development of squall are related to the mesoscale cold surge activities. The cold surge is characterized by the large amplitude gravity wave. The gravity wave is trapped by Dabie Shan Mountain in the process of propagation and the edge front is formed at the east side of Dabie Shan Mountain. The propagation of edge front shows the feature similar to Kelvin wave. The character of large amplitude gravity wave in the boundary layer is very obvious. This kind of large amplitude gravity wave trapped by the mountain may be a trigger mechanism of the squall line behind the cold front.