摘要
利用2001—2008年5—9月京津冀地区175个气象站危险天气报、灾情报告及NCEP 1°×1°再分析资料,采用自组织特征映射方法(SOM)对该地区5—9月的天气形势进行客观聚类分型,并对各型的环流特征及其主要造成的强对流天气类型进行分析。结果表明:1天气形势主要有4类:以短时强降水为主的暖湿切变型,主要出现在7、8月;以冰雹天气为主伴随短时强降水和雷暴大风的冷涡型,主要出现在6、7月;以雷暴大风为主的西北气流型,主要出现在5月;以雷暴大风和短时强降水为主的西风槽型,主要是出现在6、9月。2暖湿切变型主要特征是低层为暖湿气流和充足的水汽输送、中层为西风气流;冷涡型中高层有较强偏北气流的干冷空气侵入和低层有较好的水汽条件;西北气流型中高层有强烈的干冷空气侵入和强垂直风切变;西风槽型的动力、热力条件都较弱。3西北气流型和冷涡型出现强对流天气的频率最高,达65%以上,暖湿切变型次之,西风槽型最低。
Based on the hazardous weather reports, disaster telegraph data and NCEP 1°×1° reanalysis data from 175 stations in the Beijing, Tianjin and Hebei （HTB） areas from May to September from 2001 to 2008, the synoptic circulation patterns in the HTB area from May to September, which is objectively divided into four types by using the Self-Organizing Maps （SOM） method, are identified, and the synoptic characteristics and main severe convective weather types of each synoptic pattern are analyzed. The results indicate that： （1） There are four cluster types of synoptic patterns in the BTH area： the Warm and Wet （WWS） pattern, in which short-time rainstorms occur mainly in July and August; the Cold Vortex （CV） pattern, in which hails accompanied by short-time rainstorms and gales occur mainly in June and July; the Northwest Airflow （NA） pattern, in which gales occur mainly in May; and the West Wind Trough （WWT） pattern, in which gales and short-time rainstorms occur mainly in June and September. （2）The main features of the WWS pattern include warm and humid at low levels, superimposed by dry and cold northwest flow, sufficient water vapor transmission, and strong stratification instability; the main features of the CV pattern include the strong inrush of arid cold air in the middle-high layer from a stronger northerly airflow and good moisture condition at low levels; the main features of the NA pattern include the strong inrush of arid cold air in the middle-high layer and strong vertical wind shear; the features of the WWT pattern are not obvious convective weather, more than 65 （3）The NA and CV patterns %, and the WWS pattern comes have the highest frequency of severe second, followed by WWT pattern.
出处
《气象科技》
北大核心
2015年第2期244-249,共6页
Meteorological Science and Technology
基金
中央级公益性科研院所基本科研业务费专项(IUMKY201320-0506)
北京市气象局气象科技研发专项(2013BMBKYZX13)资助
关键词
SOM方法
强对流天气
天气形势
聚类分析
SelbOrganizing Maps （SOM） method
severe convective weather
cluster typing
Synopticcirculation pattern
