甘肃冬季一次寒潮过程分析

目的]分析甘肃冬季一次寒潮天气过程。方法]利用常规天气资料和数值预报产品,应用天气分析和诊断分析方法,对2008年12月2～5日甘肃的一次寒潮天气爆发的成因和物理量特征进行综合分析。结果]此次寒潮过程属于"横槽转竖型"。乌山脊崩溃、横槽的转竖、地面冷高压的加强南下是引发寒潮爆发的原因。西伯利亚低涡发展带动极地小股冷空气补充南下,对寒潮的爆发起到一定的促进作用。在此次寒潮过程中,涡度、温度平流等物理量也有很好的表现。结论]该研究对今后类似天气过程的预警预报和决策服务有重要的启示作用。

Analysis on a Cold Wave Weather Process in Winter in Gansu

Objective] The research aimed to analyze a cold wave weather process in winter in Gansu.Method] Based on routine observation data and numerical forecast products,formation reason and physical quantity characteristics of a cold wave process during 2-5 December,2008 were comprehensively analyzed by synoptic analysis and diagnostic analysis methods.Result] The cold wave weather belonged to "translot turning vertical type".Collapse of the Urals ridge,turning vertical of the translot and strengthening south of the ground cold high induced the cold wave.Development of the Siberian low vortex drove the small branch of the polar cold air supplement south,playing certain promoting role in outbreak of the cold wave.Physical quantities in the cold wave process also had very good expression,such as vorticity,temperature advection,etc.Conclusion] This research had important indication effect for early warning,forecast and decision service of the future similar weather process.