2012年11月10日辽西地区冷涡暴雪的动力条件分析

The Dynamical Conditions Analysis Of A Snowstorm Caused By Cold Vortex In Western Of Liaoning On 10th November 2012

文章利用NCEP/NCAR每6h间隔1°×1°再分析资料和常规气象观测资料,对2012年11月10日傍晚到11日下午发生在辽西地区的一次暴雪天气的动力条件进行分析,结果表明:高空冷涡是此次暴雪过程的主要影响系统,强降雪出现在冷涡中心前部、中层暖式切变线南侧,发生在垂直方向上高低空正涡度中心向下传的过程中,高空涡度中心下方强烈的上升运动,对暴雪的增幅起到了很大作用;强降雪位于500hPa的湿位涡负值中心附近,在湿位涡中心向下发展、向东移动的过程中,风的垂直切变和大气湿斜压性引起低层的涡度显著增加,导致上升运动的增强。

In this paper,the NCEP/NCAR reanalysis data and regular observation data were used to analyze the dynamical conditions of a snowstorm which occurred in western of Liaoning Province in the dusk of 10 th to the afternoon of 11 th November,2012.The results showed that：The upper cold vortex was the main influence system of the snowstorm,and heavy snow occurred in front of the cold eddy center and on the south side of warm shear,in the process of positive vorticity center passing down;The strong upward movement below high level vorticity center played an important role on the growth of heavy snow.Heavy snow occurred near the negative center of MPV on 500 hPa,in the process of the MPV center moved downward and eastward,vertical wind shear and wet atmospheric baroclinicity caused vorticity significantly increasing,and led to enhancement of upward movement.