河西走廊一次区域性大风强沙尘暴天气诊断

Diagnostic Analysis of a Regional Heavy Dust Storm Caused by Cold Front in Hexi Corridor

应用常规和自动加密站观测资料,对2009年4月29日发生在河西走廊的一次区域性强沙尘暴天气过程,从天气学成因、物理量要素等方面进行了诊断分析。结果表明:这是一次冷锋后大风引发的沙尘暴;沙尘暴发生在强气压梯度区;地面气象要素对冷锋过境及沙尘暴爆发有强烈反应,可以在沙尘暴预报中作为一个参考依据;沙尘暴爆发区低层辐合,高层辐散,有明显的上升运动;锋生函数和螺旋度对沙尘暴爆发区有较好的指示意义。

Based on the basic observational data and automatic weather station data, a regional heavy dust storm occurred on April 29, 2009 in Hexi Corridor was analyzed from the causes of the synoptic meteorology, physics quantity fields and so on. The results show that it was a dust storm that caused by the gale behind the cold front, and it happened in the zone of strong pressure gradient. Ground meteorological elements had a strong response to the outbreak of the dust storm, which can be used as a reference for forecast of dust storms. There was an obvious upward motion in the outbreak area of dust storm with the lower level convergence and the high - level divergence. The frontogenesis function and helicity indicated the area of dust storm very well.