###
DOI:
本文二维码信息
冷涡背景下不同类型强对流天气的成因对比分析
蔡雪薇1,2, 谌芸1,2, 沈新勇2, 郑永光1, 陶亦为1
(1.国家气象中心;2.南京信息工程大学 气象灾害教育部重点实验室 /气候与环境变化国际合作联合实验室 /气象灾害预报预警与评估协同创新中心)
Cause Analysis of Different Types of Strong Convective Weather under Cold Vortex
CAI Xuewei1,2, CHEN Yun1,2, SHEN Xinyong2, zheng yong guang1, Tao yi wei1
(1.National Meteorological Centre;2.Key Laboratory of Meteorological Disaster of Ministry of Education / Joint International Research Laboratory of Climate and Environment Change/Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters,Nanjing University of Information Science Technology)
摘要
相似文献
本文已被:浏览 201次   下载 69
投稿时间:2017-10-23    修订日期:2018-12-13
中文摘要: 利用常规气象观测资料、自动站资料、卫星、雷达和NCEP再分析资料,针对2015年8月22日冷涡背景下华北东北部和黄淮地区同时出现的不同类型强对流天气,对比分析引发不同天气的两种中尺度对流系统的演变过程及冷涡背景下不同强对流天气的成因。具体结论如下:(1)同一冷涡背景下,华北东北部位于冷涡中心外围西南象限和地面冷高压前沿,触发的分散性多单体风暴位于冷涡外围的涡旋云系中,引发以短时强降水为主的强对流天气;黄淮地区位于冷涡后部和地面冷锋前,槽后晴空区的多个对流单体,合并后形成人字形飑线系统引发短时降水、冰雹和雷暴大风天气;(2)环境热力和水汽的差异为形成不同的强对流天气提供了前提条件:华北东北部受高层暖脊影响,地面高压后部的偏东气流带来水汽输送,整层暖湿的条件利于产生强降水;黄淮地区高层有补充干冷空气,利于热力不稳定条件发展,但黄淮地区低层水汽不足,风雹天气在较干环境场中不易被触发;(3)引发不同强对流天气的对流触发机制不同,两处的初始对流均受同一地面辐合线影响,但华北东北部在地形抬升共同作用下不断新生单体;黄淮地区的初始局地热对流形成后,其前沿的辐散出流与环境风形成新的辐合,使原辐合线断裂和转向。(4)出现不同强对流天气时垂直风切变不同,黄淮风雹区的中层垂直风切变更显著,有利于形成持续性的强风暴;强对流天气发生时,华北东北部中低层风场的演变与天气尺度系统的变化有关,黄淮地区中低层风的垂直分布与中尺度对流系统的发生发展有关。
中文关键词: 冷涡 强对流 飑线
Abstract:Using the conventional meteorological data, automatic station meteorological data, satellite data, radar data and reanalysis data by NCEP,according to the different types of strong convective weather occurring in the northeast of North China and Huanghuai region in the background of cold vortex on August 22, 2015, the evolution process of two meso-scale convective systems caused by different weathers and reasons of different severe convective weather in background of cold vortex are compared and analyzed. The results show that:(1)In same cold vortex, Northeast of Huabei located in southwest quadrant of cold vortex and in front of ground cold high pressure. Dispersive multi-cell storm is located in vortex cloud at the periphery of cold vortex lead to strong convective weather dominated by short-term heavy rainfall. Huanghuai region is located in rear of cold vortex and in front of cold fronton ground. Multiple convective cells form in clear sky behind trough, forming a herringbone squall line which leads to rainfall, thunderstorms wind and hail.(2)The difference between environmental heat and water vapor provides a condition for the formation of different strong convective weather. Details as follows: The northeast of Huabei is affected by high-level warm ridge, and eastward airflow at back of ground high pressure brings water vapor transport. All layer of warm and humid conditions is conducive to generating strong precipitation. High-rises in Huanghuai region have supplementary dry and cold air, which benefit to development of thermal instability. However, the low-level water vapor in the Huanghuai is not enough, so the strong wind and hail is not easily triggered in the dry environment.(3)The convection triggering mechanism that causes different strong convective weather is different. Both initial convections are triggered along the same ground convergence line, but the terrain is rising and new element is continuously emerging in northeast of Huabei. After initial local geothermal convection in Huanghuai region is formed, the divergent outflow at leading edge forms a new convergence with ambient wind, causing the original convergence line to break and turn.(4)When there are different strong convective weather, vertical wind shear is also different. The vertical wind shear in Huanghuai is significant, which is conducive to formation of a persistent strong storm. When strong convective weather occurs, the evolution of middle and lower wind in northeast of Huabei is related to the change of weather scale system. The vertical distribution of middle and lower wind in Huanghuai is related to the occurrence and development of meso-scale convective system.
文章编号:201710230467     中图分类号:    文献标志码:
基金项目:国家自然科学基金项目(面上项目,重点项目,重大项目),国家重点基础研究发展计划(973计划)
引用文本:
蔡雪薇,谌芸,沈新勇,郑永光,陶亦为,0.[en_title][J].Meteor Mon,():-.
CAI Xuewei,CHEN Yun,SHEN Xinyong,zheng yong guang,Tao yi wei,0.Cause Analysis of Different Types of Strong Convective Weather under Cold Vortex[J].Meteor Mon,():-.