摘要
2021年6月1日和6月9日黑龙江省哈尔滨尚志市及阿城区和齐齐哈尔梅里斯区分别发生双龙卷事件。利用常规气象观测、多普勒天气雷达等资料对比分析二者的多尺度特征。结果表明:两次龙卷均发生在东北冷涡的东南象限,高空急流出口区左侧,中低层偏南气流有利于暖湿气流输送和垂直运动发展。6月1日和6月9日分别以短时强降水和雷暴大风天气为主,6月1日水汽条件、垂直运动、0~1 km高度垂直风切变和抬升凝结高度更有利于产生强龙卷,且中尺度气旋维持时间更长。干线与地面辐合线为中尺度触发机制。雷暴冷池出流与中尺度暖锋形成的伪冷锋有利于龙卷的发展和维持。龙卷出现在地面伪冷锋与干线交界处的湿区一侧,冷池前沿,龙卷母云为超级单体。暖湿气流产生的入流缺口是钩状回波发展的前兆,中等到高强度的中尺度气旋在3 km高度产生并发展,5~10 min后触地,当钩状回波与中尺度气旋同时出现时龙卷产生。
Two strong supercell tornados hit Shangzhi Acheng of Harbin and Meilisi of Qiqihar,Heilongjiang Province on 1 June("6·1"Tornado)and 9 June("6·9"Tornado)in 2021.Using the conventional meteorological observations and Doppler weather radar data,the multiscale characteristics of two events are analyzed.Both events occur in the southeast quadrant of northeastern cold vortex.The left outlet of the upper-level jet stream and the southerly jet stream at lower-level are conducive to the development of vertical movement and the transport of warm-wet air.The temperature difference between 850 hPa and 500 hPa exceeds 30℃.Two storms are both triggered by mesoscale dry-lines and convergence lines.The pseudo-cold fronts,which generate from the mesoscale warm front and the cold pool coming from the thunderstorm outflow,are beneficial to the development and maintenance of tornados.Tornados appear on the wet part of the junctions between the pseudo-cold front and dry line,and in the front of cold pool.The parent storms of tornados rapidly develop into supercells as they pass over water bodies such as reservoirs and wetlands.The warm-wet inflow gap indicates the development of hook echo.Medium to strong mesocyclones firstly appear at about 3 km high,and then go upwards and downwards,touchdown 5-10 minutes later.The tornados occur when hook echoes and mesocyclones appear simultaneously.There are also some differences between them.Short-time heavy rainfall occurs on 1 June and thunder-gust occurs on 9 June with typical sounding layer structures,but"6·1"Tornado is stronger.The atmospheric instabilities are dominated by cold advection at upper-level for"6·1"Tornado but warm advection at lower-level for"6·9"Tornado.Water vapor and vertical velocity of"6·1"Tornado is more beneficial to the development of supercell than those of"6·9"Tornado.For the vertical wind shears of 0-1 km and 0-6 km,the corrected lifting condensation level and convective available potential energy(CAPE)are 12 m·s-1,18 m·s-1,770 m and 420 J·kg-1 for"6·1"Tornado,and 10 m·s-1,33 m·s-1,1100 m and 2500 J·kg-1 for"6·9"Tornado.The stronger 0-1 km wind shears and the lower corrected lifting condensation level show the possibility of intense tornado.CAPE may be underestimated because of the spatiotemporal resolution limitation for soundings.The main cause for the long duration of"6·1"Tornado is that the mesoscale vortex at 3 km altitude maintains due to the continuous warm-wet inflow.However,the strong mesocyclone of"6·9"Tornado doesn't last that long.
作者
徐玥
邵美荣
唐凯
张礼宝
杜静
王永超
Xu Yue;Shao Meirong;Tang Kai;Zhang Libao;Du Jing;Wang Yongchao(Heilongjiang Meteorological Observatory,Harbin 150030;Harbin Meteorological Bureau of Heilongjiang,Harbin 150080;Qiqihar Meteorological Observatory of Heilongjiang,Qiqihar 161006)
出处
《应用气象学报》
CSCD
北大核心
2022年第3期305-318,共14页
Journal of Applied Meteorological Science
基金
国家重点研发计划(2018YFC1507301)。
关键词
龙卷
东北冷涡
超级单体
钩形回波
中气旋
tornado
northeastern cold vortex
supercell thunderstorm
hook echo
mesocyclone
