气象
氣象
기상
METEOROLOGICAL MONTHLY
2014年
6期
655-667
,共13页
伍志方%庞古乾%贺汉青%叶爱芬%刘运策
伍誌方%龐古乾%賀漢青%葉愛芬%劉運策
오지방%방고건%하한청%협애분%류운책
风暴分裂%左移超级单体%飑线%冰雹
風暴分裂%左移超級單體%颮線%冰雹
풍폭분렬%좌이초급단체%박선%빙박
splitting storm%left-moving supercell%squall line%hail
提2012年4月开汛后广东省接连出现强对流天气,尤其是冰雹日数更是超过历史同期平均。本文利用常规天气观测资料和雷达、自动站等非常规资料对广东首次观测到的风暴分裂中左移超级单体风暴和飑线内超级单体风暴引发的两次强对流天气过程进行了对比分析。结果表明:“4·10”冰雹和雷雨大风天气是由局地强烈加热产生的“热雷暴”发展成超级单体风暴造成的;“4·12”冰雹、雷雨大风和短时强降水天气由飑线及飑线内超级单体风暴造成的,其产生于切变线、较强冷空气南下过程中的低层暖平流和中层冷槽共同作用的环境条件下,较强的平流过程使垂直风切变明显增大;两次过程中0℃层高度都低于4月当地0℃层高度平均值。风切变矢量随高度的变化决定了左移和右移风暴的发展趋势,“4.10”风切变矢量随高度逆时针变化,使风暴分裂后左移风暴得以发展成超级单体;“4·12”风切变矢量随高度顺时针变化,有利于有组织风暴即飑线和飑线内超级单体的形成和发展,超级单体向承载层平均风的右侧运动。左移超级单体回波具有中反气旋、弱回波区和旁瓣回波及强回波中心位于其移动方向左侧等特点;飑线内超级单体的中气旋、弱回波区和强回波中心位于回波移动方向右侧,三体散射长钉长度和中层辐合厚度都很大,后侧下击暴流产生了31.1 m·s-1地面强风。
提2012年4月開汛後廣東省接連齣現彊對流天氣,尤其是冰雹日數更是超過歷史同期平均。本文利用常規天氣觀測資料和雷達、自動站等非常規資料對廣東首次觀測到的風暴分裂中左移超級單體風暴和颮線內超級單體風暴引髮的兩次彊對流天氣過程進行瞭對比分析。結果錶明:“4·10”冰雹和雷雨大風天氣是由跼地彊烈加熱產生的“熱雷暴”髮展成超級單體風暴造成的;“4·12”冰雹、雷雨大風和短時彊降水天氣由颮線及颮線內超級單體風暴造成的,其產生于切變線、較彊冷空氣南下過程中的低層暖平流和中層冷槽共同作用的環境條件下,較彊的平流過程使垂直風切變明顯增大;兩次過程中0℃層高度都低于4月噹地0℃層高度平均值。風切變矢量隨高度的變化決定瞭左移和右移風暴的髮展趨勢,“4.10”風切變矢量隨高度逆時針變化,使風暴分裂後左移風暴得以髮展成超級單體;“4·12”風切變矢量隨高度順時針變化,有利于有組織風暴即颮線和颮線內超級單體的形成和髮展,超級單體嚮承載層平均風的右側運動。左移超級單體迴波具有中反氣鏇、弱迴波區和徬瓣迴波及彊迴波中心位于其移動方嚮左側等特點;颮線內超級單體的中氣鏇、弱迴波區和彊迴波中心位于迴波移動方嚮右側,三體散射長釘長度和中層輻閤厚度都很大,後側下擊暴流產生瞭31.1 m·s-1地麵彊風。
제2012년4월개신후광동성접련출현강대류천기,우기시빙박일수경시초과역사동기평균。본문이용상규천기관측자료화뢰체、자동참등비상규자료대엄동수차관측도적풍폭분렬중좌이초급단체풍폭화박선내초급단체풍폭인발적량차강대류천기과정진행료대비분석。결과표명:“4·10”빙박화뇌우대풍천기시유국지강렬가열산생적“열뇌폭”발전성초급단체풍폭조성적;“4·12”빙박、뇌우대풍화단시강강수천기유박선급박선내초급단체풍폭조성적,기산생우절변선、교강랭공기남하과정중적저층난평류화중층랭조공동작용적배경조건하,교강적평류과정사수직풍절변명현증대;량차과정중0℃층고도도저우4월당지0℃층고도평균치。풍절변시량수고도적변화결정료좌이화우이풍폭적발전추세,“4.10”풍절변시량수고도역시침변화,사풍폭분렬후좌이풍폭득이발전성초급단체;“4·12”풍절변시량수고도순시침변화,유리우유조직풍폭즉박선화박선내초급단체적형성화발전,초급단체향승재층평균풍적우측운동。좌이초급단체회파구유중반기선、약회파구화방판회파급강회파중심위우기이동방향좌측등특점;박선내초급단체적중기선、약회파구화강회파중심위우회파이동방향우측,삼체산사장정장도화중층복합후도도흔대,후측하격폭유산생료31.1 m·s-1지면강풍。
In April 2012,a series of severe thunderstorms which produced more hails than normal were seen in the Guangdong Province.This paper analyses two severe convective weather events,which are one left-moving supercell in the splitting storm that was observed first time in Guangdong and one supercell in a squall line,by using conventional meteorological observations,Doppler radar data and surface automatic weather station observations.The results show that a “thermal thunderstorm”initiated by local intense heating developed into a supercell storm which produced hails and severe wind gusts on 10 April.On 12 April,one squll line and the supercell which brought hails,severe wind gusts and torrential rains in a very short time were developed by the role of low-level warm advection and middle-level cold trough in the process of a shear line and a strong cold front moving southeastward,while the vertical wind shears went up by the advection process.The 0℃layer heights for the two events were lower than the local mean value in April.It was found that the changing of wind shear vector with heights determined the development trend of left-moving and righ-moving storm:The counterclockwise changing with heights of wind shear vector initiated a left-moving storm developed to a hailstorm after storms splitting on 10 April;and the clockwise changing was conducive for a squall line to be well organized and developed,and the supercell in the squall line moved to the right of the mean wind of the bearing layer.The left-moving supercell was characterized by a anti-mesocyclone,WER,side-lobe echoes and a strong echo center on the left side.The supercell in the squall line featured a mesocyclone,WER,side-lobe echoes and a strong echo center on the right side,the long TBSS and massive mid-level convergence,with 31.1 m·s-1 backside downburst.