中文摘要：

本文首先给出冷涡的定义,然后根据此定义识别出2009—2013年4—9月的冷涡有65个,分析冷涡的时空分布特征及生命史特征发现：冷涡的月变化特征明显,7月冷涡个数和维持的天数最多。冷涡主要发生在贝加尔湖东部、蒙古的东部和东北的西北部地区,生命史大多为3 d。利用自动站小时雨量资料统计分析冷涡背景下短时强降水特征及其与冷涡的关系,结果表明：冷涡背景下的短时强降水主要集中在京津和河北东南部,以及东北平原地区,7月最多,日变化表现为午后至傍晚时段多发。冷涡的各个时期都能产生短时强降水,发展时期最多,降水主要位于冷涡中心的东南部和西南部,不同类型的冷涡降水分布不同。

英文摘要：

Cold vortex is firstly defined in this paper.And then 65 cold vortexes are identified from April to September of 2009 — 2013 based on the definition.Their spatio-temporal distributions are studied.The monthly variation of cold vortexes is obvious,and the most of them occur in July,mainly from the east of Lake Baikal and Mongolia to the northwest of Northeast China.Most cold vortexes live for more than 3days.Hourly rainfall data of automatic weather station are used to analyze the characteristics of the severe short-time precipitation under the background of cold vortex and its relations with cold vortex.The results show that severe short-time precipitation accompanying cold vortex mainly occurs in the southeast of Hebei,Beijing,Tianjin and the Northeast Plain in July.Besides,such events are often seen from afternoon to evening.Severe short-time precipitation can occur in any phases of cold vortexes,mainly during the developing phases.Besides,it is located mainly in the southeast and southwest of vortex center.And the distribution of severe short-time precipitation is different in different cold vortexes.