摘要
利用常规地面气象观测资料、NCEP/NCARFNL1°×1°网格点逐6h再分析资料,对2018年6月20日浙江省一次暴雨过程的主要环流系统、等熵位涡、垂直螺旋度等进行了天气动力学诊断分析。结果表明:850hPa低涡切变、对流层中层冷空气、200hPa南亚高压、副热带高压是此次暴雨过程发生的主要影响系统;700hPa上的正垂直螺旋度中心对暴雨的发生有良好的指示意义;等熵位涡的演变和形态对冷空气活动有较好的视踪作用,等熵位涡中心两侧气流辐合,有利于低压系统发展,高层等熵位涡与冷空气活动有较好的对应关系,等熵位涡大值区偏南侧的移动与强降水落区有较好的对应关系。
Based on conventional meteorological data and the 6-h FNL 1°×1°reanalysis data from National Centers for Environment Prediction(NCEP)/National Centers of Atmospheric Research(NCAR),we conducted the dynamic diagnosis analysis on a rainstorm event in Zhejiang province on June 20,2018,which includes the major circulation systems,isentropic potential vorticity,and vertical helicity.The results indicated that the major influencing systems for this rainstorm event are the low-level vortex shear at 850 hPa,weak cold air intruded in the middle troposphere,the South Asian Anticyclone and the Subtropical High at 200 hPa.Positive vertical helicity center at 700 hPa is a good indicator of the occurrence of rainstorm events.The evolution and form of isentropic potential vorticity are indicative of cold air activity.The convergence of airflow on both sides of the isentropic vorticity center is favorable for the development of surface low pressure.High-level isentropic potential vorticity corresponds well to the cold air activity,and precipitation areas are influenced greatly by the movement of areas with large isentropic potential vorticity values towards the south.
作者
毛程燕
李浩文
龚理卿
孙杭媛
王健疆
陈慧玲
MAO Cheng-yan;LI Hao-wen;GONG Li-qing;SUN Hang-yuan;WANG Jian-jiang;CHEN Hui-ling(Quzhou Meteorological Service,Quzhou 324000,China;Guangzhou Meteorological Observatory,Guangzhou 511430,China)
出处
《气象与环境学报》
2019年第6期8-13,共6页
Journal of Meteorology and Environment
基金
浙江省气象局预报员专项项目(2018YBY05)
衢州市气象局一般项目(2018QZ08)共同资助
关键词
系统耦合
垂直螺旋度
等熵位涡
诊断分析
System coupling
Vertical helicity
Isentropic potential vorticity
Diagnostic analysis
