1956-2011年黑龙江省龙卷风气候特征

摘要

利用富士达—皮尔森强度分类法对1956—2011年黑龙江省229个龙卷风样本进行分类，分析龙卷风事件的时空分布特征，探讨典型龙卷风个例的环流背景及形成机制。结果表明：1956—2011年黑龙江省龙卷风灾害具有明显的时空分布特征，20世纪60—80年代龙卷风活动频繁，90年代龙卷风发生频次最少，2001—2011年龙卷风发生频次略增加。龙卷风主要集中发生在夏季，以7月发生最多，且多出现在午后至傍晚。对龙卷风空间分析发现黑龙江省绥化地区是龙卷风多发区，与该地区的地理位置、气候条件和大气环流特征有关。不稳定的形势场是龙卷风产生的基础，暖湿气流的输送和冷暖空气的强对流运动为龙卷风的产生提供了有利条件。%Tornadoes events from 1956 to 201 1 in Heilongjiang province were classified by a Fujitec-Pearson meth-od.Temporal and spatial characteristics of tornadoes were analyzed,and the related large-scale circulation and for-mation mechanism for typical cases were discussed.The results show that there is apparent temporal and spatial distribution for those tornado events from 1956 to 201 1 in Heilongjiang province.The frequency of tornado is high-er during 1960s to 1980s,while it is the lowest in 1990s,and it increases during 2001 to 2011.Most tornadoes oc-cur in summer,especially in July,and most are from afternoon to early evening.Spatial distribution of tornadoes suggests that frequent area of tornadoes is in Suihua of Heilongjiang province,which is related with the local geo-graphical location,climatic conditions and atmospheric circulation.Unstable situation,warm moisture transports and the vertical motion of cold and warm air provide the favorable conditions for generation of tornadoes.