PDF《如皋一次罕见的飑线天气过程》

第30卷第4期 气象科学Vo.

l

30 , No.

4 2010年 8月 SCIENT I A M ETEOROLOG ICA SIN ICA Aug. ,

2010 刘娟, 周昌云, 曹乃和, 等. 如皋一次罕见的飑线天气过程. 气象科学, 2010, 30( 4):

564 568. L iu Juan , Zhou Changyun, Cao N aihe , et a. l Process analysis on a rare squall line w eathr in Rugao . ScientiaM eteorologica S in ica , 2010, 30( 4):

564 568. 如皋一次罕见的飑线天气过程 刘娟周昌云 曹乃和 赵阳蔡娈卉 (如皋市气象局, 江苏 如皋 226574) 摘要针对 2008年 7月 15日下午在如皋境内生成和发展的飑线天气过程, 利用常规和非 常规气象资料, 对其进行精细化剖析, 结果发现: ( 1)强对流天气发生在副高东退、 西风槽跟进的形 势背景下, 有从渤海低压穿过的冷锋为影响系统, 如皋上空是对流性不稳定的大气层结, 还有如皋 地面中尺度天气系统的抬升力和激烈的热对流抬举力合二为一的共同触发, 促使储有大量潜能的 暖湿空气在如皋境内发生、 发展成飑线. ( 2)如皋境内的中尺度系统是由苏中地区地表性质、 地理 环境水平分布差异大, 所产生的气温水平分布不均而引起的, 尤其是如皋境内高沙土地区的土质分 布情况更为特殊. ( 3)雷暴云和飑线的产生、 发展的位置与中尺度系统位置近似重合, 飑线上强雷 暴云的移动方向与

7 k m 以下高空风主导风向一致. 关键词 飑线 潜能 过程剖析 分类号 P458 .

2 文献标识码 B 收稿日期:

2009 06

05 ;

修改稿日期:

2009 09

07 基金项目: 江苏省重大科技支撑与自主创新示范工程项目 ( BE2008618). 第一作者简介: 刘娟 (

1982 ),女, 江苏如皋, 学士, 助工, 主要从事公共气象服务和气象观测工作. liujuan158@

163 . com Process analysis on a rare squall line weathr in Rugao L iu Juan Zhou Changyun Cao Na ihe Zhao Yang Cai Luanhui (R ugaoM eteorological Bureau, Jiang su Rugao 226574, China ) Abstract Conventional and unconventionalmeteorological data have been usea to analyge in detail the generation and the development of squall linew eather process wh ich occurred in Rugao of Jiangsu on Ju ly

15 afternoon ,

2008 . The resu lts showed that ( 1) The strong convectivew eather occurred under such situation background that subtroplc h igh w ent back eastw ard , w esterly trough w ent forw ard , a cold front w hich passed through low pressure in Bohai Sea affected the w eather system. Convectively unstab le at mospheric stratification over Rugao appeared , the lifting force of m esoscale w eather system has been combmed w ith intense ther mal convection to trigger and provide potential energy reservoir of w ar m and w et air , wh ich led to generation and development of squall line in Rugao. In fac, t in that day in Jiangsu above mentioned w eather situation ofRugaow as unique. ( 2) M esoscale system in Rugao is related to the surface nature ofm idd le Jiangsu and intense difference of horizontal distribu tion of geographical environ men,t w hich lead to nonun ifor m horizontal d istribution of air te mperature, especially Rugao belongs to h igh sand area . ( 3) The locaton of thunderstor m and squall line w as close to that of mesoscale system, the movement direction of strong thunderstor m over squall line is coincident w ith predom inantw ind d irec tion of upper levelw ind of less than

7 km altitude . K ey words Squall line Potential energy Process analysis 引言由许多雷暴单体 (也可为超级单体 )侧向排列 成线时为飑线, 飑线上的每个单体可不相干扰, 当强 雷暴云来临的瞬间, 风向突变、 风力猛增、 由静风突 然加强到大风以上 ( 8~ 10级的强风 );