呼伦贝尔一次短时强降水特征分析-中国农学通报.PDF

中国农学通报 2014,30(26):219-224 Chinese Agricultural Science Bulletin 呼伦贝尔市一次短时强降水特征分析 常 煜，刘 勇 （内蒙古呼伦贝尔市气象局，内蒙古呼伦贝尔021008） 摘 要：为了研究呼伦贝尔市短时强降水特征，防范短时强降水引发的洪涝灾害对农业产生的影响，利用 地面逐时加密观测资料、NCEP 再分析资料和卫星云图资料，对2009 年7 月12 日呼伦贝尔市出现局地短 时强降水天气成因进行分析。结果表明：前倾槽结构为此次短时强降水提供了非常有利的大尺度环 境。短时强降水发生在低层暖湿切变线辐合区与高空弱脊辐散区相叠置区域，MCC 发展阶段的入流边 界。短时强降水落区具有低层高温高湿强对流不稳定层结，强的垂直风切变，强烈上升运动，并伴有螺 旋度正值区的特征，中高层干冷空气入侵触发了不稳定能量释放，产生此次短时强降水天气。 关键词：局地短历时强降水；前倾槽；MCC 中图分类号：P458 文献标志码：A 论文编号：2013-2951 AnalysisofASevereShort-termPrecipitationinHulunBuirCity ChangYu,LiuYong (HulunBuirMeterologicalBureau,HulunBuirInnerMongolia021008) Abstract:Inordertostudythecharacteristicsofsevereshort-termprecipitationinHunlunBuirandtoguard against the impact on agriculture from flood disasters caused by severe short-term precipitation, using automaticmeteorogicalobservingdata,NCEPreanalysisdataandsatelliteimages,thecausesofasevereshort- termprecipitationoccurredinHulunBuiron 12July2009werepreliminarilystudied.Theresultsshowedthat: upper forward trough provided favorable large scale condition for the severe short-term precipitation, it occurredoncoincidenceareabetweentheconvergencebywarmshearlineinlowlevelandthedivergenceby weakridgeinhighlevel,appearedinflowboundaryofthedevelopmentstageofMCC.Theatmospherefeature ofthesevereshort-termprecipitationexhibitedstrongconvectiveinstabilityofhigherhumidityandhigher temperatureinlowlevel,strengthenverticalwindshear,ascendingmotionandpositivehelicity.Theconvective instabilitywasreleasedbytheinvasionofdryairinthemiddletroposphere,thatcausedthesevereshort-term precipitation. Keywords:severeshort-termprecipitation;upperforwardtrough;MCC 0 引言