摘要
利用常规探测、地面加密观测、T213数值预报产品和FY-2c/2d红外卫星云图资料,对2008年5月2日河西走廊东部飑线引发的大风强沙尘暴过程进行了天气动力诊断和中尺度分析。结果表明:飑线引发的强风暴是产生强沙尘暴的根本原因。河西走廊东部处在不稳定大气层结中,500hPa阶梯短波槽为飑线提供了大尺度环流背景;700hPa变形场是飑线的触发系统;地面热低压的发展加大了冷锋前后的气压和温度梯度,为对流发展提供了热力不稳定条件;高空急流对于飑线的生成、发展具有重要的作用。
Using conventional survey, ground intensive observations, numerical prediction product T213 and FY - 2c/2d infrared satellite cloud image, synoptic - dynamical diagnosis and mesoscale analysis are carried on gale and strong sandstorm process initiated by squall line on May 2, 2008 in east of Hexi corridor. The results show that strong storm initiated by squall line produced the strong sandstorm. East of Hexi Corridor is in instable atmosphere stratification. Large scale circu- lation background is provided by stepped short wave trough of 500 hPa for squall line. Deforma- tion field of 700 hPa is triggering system of squall line. Gradient of pressure and temperature be- fore and after cold front is enlarged by development of around thermal low pressure, hv which thermal energy stability condition is provided for convection development. Upper air jet stream has vital role for production and development of squall line.
出处
《气象》
CSCD
北大核心
2009年第3期42-48,共7页
Meteorological Monthly
基金
甘肃省气象局2007年重点科研项目"数值预报产品在河西精细化预报中的应用"
关键词
强沙尘暴
飑线
发生机制
物理特征
strong sandstorm squall line production mechanism physical characteristic
