湿位涡及其不可渗透性在江淮流域一次暴雨过程中的应用

为了对暴雨天气进行更准确地分析和提前预报,结合常规观测资料、NCEP1°×1°再分析资料,利用湿位涡正压项(MPV1)、斜压项(MPV2)及其不可渗透性原理,分析了2011年6月13日~15日发生在中国长江流域的一次暴雨过程。研究结果表明:暴雨区邻近850hPa上MPV1的零线,即正值与负值的过渡区,这对暴雨落区有指示作用。且湿位涡在850hPa上满足MPV10同时MPV20的条件,这种配置有利于强降水的产生,因此可作为预报暴雨的一个有效辅助工具。在850hPa上,湿位涡高值区与地面降水落区对应良好,根据湿位涡不可渗透性原理,若将MPV异常高值区与等θe线结合起来,能在长江流域的暴雨预报中起到良好的指示作用。

Application of Moist Potential Vorticity and its Impermeability during the Process of a Torrential Rain Occurring along the Yangtze and Huai River

To analyze the rainstorm weather more precisely and predict in advance,with the conventional meteorological observation data,1° × 1°NCEP reanalyzed data,the impermeability theorem of the moist potential vorticity （MPV）,as well as the vertical component of moist potential vorticity（MPV1）and the horizontal component of moist potential vorticity （MPV2）,are utilized to diagnose the process of a typical torrential rain occurring along the Yangtze and Huai River from June 13 to June 15 in 2011.The results show that：The heavy rain nears the zero line of MPV1.At the level 850hPa,the condition （MPV1 〉 0 and MPV2 〈 0） is beneficial to the occurring of heavy rain,therefore can be used effectively in predicting torrential rain.At 850 hPa,MPV high-value area corresponds to the precipitation area on the ground.According to the impermeability theorem of the MPV,there is a good indication of heavy rain along the Yangtze and Huai River if MPV anomaly high-value area matches equivalent potential temperature （） line well.