摘要
为提高对东北地区雷暴大风的分析和预报能力,基于2017—2021年东北地区自动气象站、闪电定位仪、葵花8号卫星综合判识雷暴大风天气,利用ERA5再分析资料计算强对流物理量和东北冷涡中心及半径等特征参量,研究东北地区雷暴大风的观测特征及其与东北冷涡(简称“冷涡”)的关系。结果表明:(1)东北地区雷暴大风(简称“总体”)集中出现在蒙古高原至大兴安岭以西、东北平原和辽宁沿海。冷涡导致的雷暴大风占总体雷暴大风的50.6%,辽河平原是冷涡雷暴大风最高发区域。东北地区总体和冷涡雷暴大风均具有单峰分布的日变化特征,在午后发生频率最高,但是深夜和上午时段雷暴大风多与冷涡有关,占比达75%。(2)雷暴大风逐小时出现的站数(简称“站数”)大多小于10次,站数大于10次的雷暴大风个例中,冷涡个例占56.5%,高于非冷涡。相比于非冷涡,冷涡雷暴大风发生在更干冷、850与500 hPa强温度直减率以及强的风垂直切变和风暴承载层环境中。(3)冷涡系统的不同象限出现的雷暴大风占冷涡雷暴大风的百分比从大到小依次为东南象限(73.5%)、西南象限(17.5%)、东北象限(7.5%)和西北象限(1.5%)。冷涡外围的雷暴大风次数多于冷涡本体,集中出现在冷涡东南象限距离冷涡中心0.5—2个冷涡半径的范围内,该区域大气中层存在干层、低层存在大的温度垂直递减率、中等以上的风垂直切变和更大的风暴承载层风速,并且更容易受低空切变线的影响,这也是冷涡雷暴大风集中出现在该区域的原因。(4)导致雷暴大风的冷涡中心集中于(45°—55°N,111°—128°E),其中导致区域性雷暴大风的冷涡中心的频次分布为南北向,集中在116°E和122°E处。造成区域性雷暴大风的冷涡中心和最外围环流的位势高度均低于造成局地雷暴大风的冷涡,春、秋季差异更明显;冷涡半径在8月略大于导致局地�
To improve the analysis and forecast ability of thunderstorm gusts(TGs)in Northeast China,climatic characteristics of TGs in Northeast China and their relation with Northeast China Cold Vortex(NCCV)are studied.TGs are identified based on comprehensive analysis of data collected at automatic weather stations and from lighting locators and Himiwari-8 satellite.In addition,the ERA5 reanalysis dataset is used to calculate the centers and radius of NCCV.The results show that TGs in Northeast China mainly occur in the regions from the Mongolian plateau to the west of the Greater Khingan mountains,Northeast China plain and the coastal area of Liaoning.About 50.6%of TGs are caused by NCCV and Liaohe plain is the area with the highest occurrence frequency of TGs caused by NCCV.The diurnal variation of TGs occurrence shows a high frequency in the afternoon,and the TGs caused by NCCV are more frequent in the late night and morning,accounting for 75%.The number of stations with TGs in one hour is generally less than 10,while the cases of regional TGs occurring at more than 10 stations are mostly related to NCCV and account for 56.5%.Compared with TGs not caused by NCCV,TGs caused by NCCV occur in a drier and colder environment with strong temperature lapse rate between 850 hPa and 500 hPa,strong vertical wind shear and storm bearing layer.The percentages of TGs occurring in different quadrants of NCCV in the NCCV TGs are 73.5%in the southeast quadrant,17.5%in the southwest quadrant,7.5%in the northeast quadrant and 1.5%in the northwest quadrant in descending order.The frequency of TGs occurring in the periphery of NCCV is more than that in the NCCV itself,and they are concentrated within 0.5—2 times of NCCV radius from the southeast quadrant of NCCV to the center of NCCV.In this area,there is a dry layer in the middle atmosphere,a large vertical temperature lapse rate in the lower atmosphere,a medium or higher vertical wind shear and a larger wind speed in the storm carrying layer,and they are more vulnerable to the impact
作者
杨磊
郑永光
YANG Lei;ZHENG Yongguang(Liaoning Meteorological Disaster Monitoring and Early Warning Center,Shenyang 110166,China;National Meteorological Centre,Beijing 100081,China)
出处
《气象学报》
CAS
CSCD
北大核心
2023年第3期416-429,共14页
Acta Meteorologica Sinica
基金
国家重点研发计划重点专项(2022YFC3004104)
中国气象局创新发展专项(CXFZ2022J059、CXFZ2022J003、CXFZ2023J013)
中国气象局重点创新团队(CMA2022ZD07)
风云卫星应用先行计划(FY-APP-2021.0114)
环渤海区域科技创新项目(QYXM202102)。
关键词
东北冷涡
雷暴大风
强对流
东北地区
Northeast China Cold Vortex
Thunderstorm gust
Strong convection
Northeast China
