摘要
文章利用常规观测资料、NCEP再分析资料及卫星资料,对长沙城区“6.9”“8.17”两次极端暴雨进行对比分析,寻找共性和差异。结果表明:两次暴雨以对流性为主,最大雨强均超过90 mm/h,“6.9”暴雨发生在副热带高压外围,“8.17”暴雨发生在副热带高压控制区内;两次暴雨水汽来源相同,比湿均大于16 g/kg,整层可降水量均超过130 mm;低层假相当位温中心均大于360 K;均在高层形成了不稳定形势,且能量主要集中在低层;两次过程均由β中尺度对流单体移入发展影响,且中尺度系统均移动缓慢,影响时间长;两次暴雨在发生前都是晴好天气,地面处于高温高湿状态,当有冷平流时,可触发局部对流天气,地面倒槽及辐合线对对流的发展有加强作用。
In this paper,the conventional observation data,NCEP reanalysis data and satellite data are used to compare and analyze the two extreme rainstorm of"6.9"and"8.17"in Changsha urban area,looking for similarities and differences.The results show that the two rainstorm are mainly convective,and the maximum rainfall intensity is more than 90 mm/h.The"6.9"rainstorm occurred in the periphery of the subtropical high,and the"8.17"rainstorm occurred in the control area of the subtropical high.The water vapor sources of the two rainstorm are the same,the specific humidity is more than 16 g/kg,and the precipitation of the whole layer is more than 130 mm.The false equivalent potential temperature center of the lower layer is more than 360 K.The unstable situation is formed in the upper layer,and the energy is mainly concentrated in the lower layer.Both processes are influenced by the migration and development of beta mesoscale convective cells,and the mesoscale system moves slowly with a long impact time.Both of the two rainstorm were fine weather before the occurrence,and the ground was in a state of high temperature and high humidity.When there was cold advection,it could trigger local convective weather.The ground trough and convergence line strengthened the development of convection.
作者
方韵
银莲
申天瑶
陈婷
魏雯婷
王晋宁
Fang Yun;Yin Lian;Shen Tianyao;Chen Ting;Wei Wenting;Wang Jinning(Changsha Meteorological Bureau,Changsha National Testbed for Comprehensive Meteorological Observation of CMA,Changsha 410205;NO.96732 Troop of PLA,Shaoyang 422000)
出处
《气象水文海洋仪器》
2025年第4期61-65,共5页
Meteorological,Hydrological and Marine Instruments
基金
湖南省气象局研究型业务预报预测专项“长沙地区三类非典型天气概念模型研究”(XQKJ21C001)
湖南省气象局创新发展专项“长沙雨季降水的变化规律及其与西风带和副高的关联性分析与预测”(CXFZ2024-QNZX06)资助。
关键词
极端暴雨
对比分析
物理量场
中尺度云团
extreme rainstorm
comparative analysis
physical quantity field
mesoscale cloud cluster
