梅雨锋暴雨中尺度对流系统的组织特征和触发条件分析
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摘要
利用常规气象观测、地面加密自动站和多普勒天气雷达资料,结合WRF(Weather Research and Forecast)模式模拟资料,对2015年6月26—28日长江中下游的一次梅雨锋暴雨过程中尺度对流系统(Mesoscale Convective System,MCS)的组织特征和对流触发条件进行分析。结果表明:1)暴雨过程线状MCS在发展初期表现为东西向雨带不断的"后部建立"以及随后对流单体的"列车效应";在发展成熟期,对流单体向东北—西南向发展,形成多个近乎平行的东北—西南向短雨带。呈现2种尺度的对流组织方式:新生对流单体沿着单个雨带向东北方向的"列车效应"和短雨带沿着线状M CS向东平流的"列车带"效应。2)低空急流的持续加强为对流的发生发展提供了条件性不稳定和对流有效位能,偏南暖湿气流在向东北推进的过程中,在风速辐合处被强迫抬升至自由对流高度,释放不稳定能量,触发对流。3)对流雨带内近地面向南的冷出流与低层西南暖湿气流的持续交汇和相互作用有利于新单体生成发展,使雨带得以维持。
A Meiyu front torrential rain event occurred over the middle and lower reaches of the Yangtze River on 26—28 June 2015.The organization modes and initiation conditions of Mesoscale Convective Systems( MCS) are analyzed by using the conventional meteorological observation data,the dense surface automatic meteorological stations data,Doppler weather radar data and the simulated data from WRF( Weather Research and Forecast) model.The results are as follows:( 1) many types of organization modes are found in the development of the linear MCS.Constantly back building of the east-west oriented rainbands and subsequent echo-training of convective cells are the main development modes of the MCS in the initial stage.The convection cells develop in the direction of NESW and form several short parallel convective rainbands in a nearly NE-SW direction in the mature stage. Two scales of convective organization modes are found: one is northeastward echo-training of newconvective cells along individual rainbands,and the other is eastward band-training of the NE-SW oriented short rainbands along the linear MCS.( 2) The continuous enhancement of low-level jet provides the conditional instability and convective available potential energy for the generation and development of convections.The southerly warm and moist air is lifted to the level of free convection,releasing the unstable energy and triggering convection at the convergence of wind speed.( 3) The consistent interactions between the cold outflowof convective cells and the low-level southwest warm and moist air are favorable for the generation and development of newcells,maintaining the rainbands.
A Meiyu front torrential rain event occurred over the middle and lower reaches of the Yangtze River on 26—28 June 2015.The organization modes and initiation conditions of Mesoscale Convective Systems( MCS) are analyzed by using the conventional meteorological observation data,the dense surface automatic meteorological stations data,Doppler weather radar data and the simulated data from WRF( Weather Research and Forecast) model.The results are as follows:( 1) many types of organization modes are found in the development of the linear MCS.Constantly back building of the east-west oriented rainbands and subsequent echo-training of convective cells are the main development modes of the MCS in the initial stage.The convection cells develop in the direction of NESW and form several short parallel convective rainbands in a nearly NE-SW direction in the mature stage. Two scales of convective organization modes are found: one is northeastward echo-training of newconvective cells along individual rainbands,and the other is eastward band-training of the NE-SW oriented short rainbands along the linear MCS.( 2) The continuous enhancement of low-level jet provides the conditional instability and convective available potential energy for the generation and development of convections.The southerly warm and moist air is lifted to the level of free convection,releasing the unstable energy and triggering convection at the convergence of wind speed.( 3) The consistent interactions between the cold outflowof convective cells and the low-level southwest warm and moist air are favorable for the generation and development of newcells,maintaining the rainbands.
引文
Bluestein H B,Jain MH,1985.Formation of mesoscale lines of precipitation:severe squall lines in Oklahoma during the spring[J].J Atmos Sci,42:1711-1732.
Chappell C F,1986.Quasi-stationary convective events[M].Boston:American Meteorological Society:289-309.
Chen G T J,Yu C C,1988.Study of low-level jet and extremely heavy rainfall over northern Taiwan in the Meiyu season[J].Mon Wea Rev,116:884-891.
Chen G T J,Wang C C,Liu S C S,2003.Potential vorticity diagnostics of a Meiyu front case[J].Mon Wea Rev,131:2680-2696.
Ding Y H,1992.Summer monsoon rainfalls in China[J].J Meteor Soc Japan,70:373-396.
Ding Y H,Chan J C,2005.The East Asian summer monsoon:an overview[J].Meteorol Atmos Phys,89:117-142.
丁治英,王爽,高松,2017.一次华南双雨带暴雨中的位涡演变与雨带间的相互作用[J].大气科学学报,40(5):653-662.Ding Z Y,Wang S,Gao S,2017.Potential vorticity evolution of a double rainbands storm in South China and interactions between the rain-bands[J].Trans Atmos Sci,40(5):653-662.(in Chinese).
Doswell C A,Brooks H E,Maddox R A,1996.Flash flood forecasting:an ingredients-based methodology[J].Wea Forecasting,11:560-581.
高守亭,孙建华,崔晓鹏,2008.暴雨中尺度系统数值模拟与动力诊断研究[J].大气科学,32(4):854-866.Gao S T,Sun J H,Cui X P,2008.Numerical simulation and dynamic analysis of mesoscale torrential rain systems[J].Chin J Atmos Sci,32(4):854-866.(in Chinese).
何斌,何锋,范晓红,等,2013.一次长江中下游梅雨锋暴雨过程的诊断分析[J].高原气象,32(4):1074-1083.He B,He F,Fan X H,et al.,2013.Diagnostic analysis on a meiyu front rainstorm process in Mid-and Low-reaches of Yangtze River[J].Plateau Meteor,32(4):1074-1083.(in Chinese).
鞠永茂,王汉杰,钟中,等,2008.一次梅雨锋暴雨云物理特征的数值模拟研究[J].气象学报,66(3):381-395.Ju Y M,Wang H J,Zhong Z,et al.,2008.A simulation study on the characteristics of cloud microphysics of rain storm in a Meiyu front[J].Acta Meteorlogica Sinica,66(3):381-395.(in Chinese).
Luo Y L,Gong Y,Zhang D L,2014.Initiation and organizational modes of an extreme-rain-producing mesoscale convective system along a Mei-Yu front in East China[J].Mon Wea Rev,142(1):203-221.
苗春生,刘春,王坚红,等,2017a.FY-3A水汽资料在江淮梅雨强降水系统湿动力诊断中的应用[J].大气科学学报,40(1):36-47.Miao C S,Liu C,Wang J H,et al.,2017.Application of moisture data from the FY-3A satellite in moisture-dynamic diagnosis of Meiyu heavy precipitation systems over the Jianghuai Valley[J].Trans Atmos Sci,40(1):36-47.(in Chinese).
苗春生,吴琼,王坚红,等,2017b.淮河流域大别山地形对梅雨期暴雨低涡影响的模拟研究[J].大气科学学报,40(4):485-495.Miao C S,Wu Q,Wang J H,et al.,2015.Comparison of dry-cold intrusion in north and south heavy rainfall zones during Meiyu front rainstorms in ChangjiangHuaihe valleys[J].Trans Atmos Sci,38(1):76-84.(in Chinese).
闵锦忠,张申,杨婷,2018.一次梅雨锋暴雨发生发展机制的诊断与模拟[J].大气科学学报,41(2):155-166.Min J Z,Zhang S Y,Yang T,2018.Diagnosing analysis and numberical simulation of formation and development mechamism of a rainstorm associated with Meiyu front[J].Trans Atmos Sci,41(2):155-166.(in Chinese).
Schumacher R S,Johnson R H,2005.Organization and environmental properties of extreme-rain-producing mesoscale convective systems[J].Mon Wea Rev,133:961-976.
Schumacher R S,Johnson R H,2006.Characteristics of U.S.extreme rain events during 1999-2003[J].Wea Forecasting,21(1):69-85.
孙建华,赵思雄,2002.华南“94·6”特大暴雨的中尺度对流系统及其环境场研究Ⅰ.引发暴雨的β中尺度对流系统的数值模拟研究[J].大气科学,26(4):541-557.Sun J H,Zhao S X,2002.A Study of mesoscale convective systems and its environmental fields during the June 1994 record heavy rainfall of South China Part I:a numerical simulation study of meso-βconvective system inducing heavy rainfall[J].Chin J Atmos Sci,26(4):541-557.(in Chinese).
陶诗言,张小玲,张顺利,2004.长江流域梅雨锋暴雨灾害研究[M].北京:气象出版社.Tao S Y,Zhang X L,Zhang S L,2004.Study of Meiyu rainstorm disaster over Yangtze River[M].Beijing:China Meterological Press.(in Chinese).
Wang H,Luo Y L,Jou B J D,2014.Initiation,maintence,and properties of convection in an extreme rainfall event during SCMREX:observational analysis[J].J Geophys Res,119:13206-13232.
王晓芳,胡伯威,李红莉,等,2011.梅雨期一个伴有前导层状降水对流线的结构特征[J].高原气象,30(4):1052-1066.Wang X F,Hu B W,Li H L,et al.,2011.Stream structure of a convective line with leading stratiform precipitation during Meiyu period[J].Plateau Meteor,30(4):1052-1066.(in Chinese).
尹洁,郑婧,张瑛,等,2011.一次梅雨锋特大暴雨过程分析及数值模拟[J].气象,37(7):827-837.Yin J,Zheng J,Zhang Y,et al.,2011.Analysis and numerical simulation of a heavy rainfall event along the Meiyu front[J].Meteor Mon,37(7):827-837.(in Chinese).
Zhang M,Zhang D L,2012.Subkilometer simulation of a torrential-rain-producing mesoscale convective system in East China.Part I:model verification and convective organization[J].Mon Wea Rev,140:184-201.
张瑞萍,马旭林,盛文斌,等,2014.2011年6月江淮梅雨暴雨主要影响系统特征[J].大气科学学报,37(3):366-377.Zhang R P,Ma X L,Sheng W B,et al.,2014.Characteristics of the main influential system of Jianghuai Meiyu Storm in June 2011[J].Trans Atmos Sci,37(3):366-377.(in Chinese).
赵思雄,陶祖钰,孙建华,等,2004.长江流域梅雨锋暴雨机理的分析研究[M].北京:气象出版社.Zhao S X,Tao Z Z,Sun J H,et al.,2004.Analysis and research on Meiyu front rainstorm mechanism in Yangtze River Valley[M].Beijing:China Meterological Press.(in Chinese).
赵玉春,2011.梅雨锋对引发暴雨的中尺度对流系统发生发展影响的研究[J].大气科学,35(1):81-94.Zhao Y C,2011.Impacts of Meiyu front upon the initiation and development of mesoscale convection systems producing rainstorms[J].Chin J Atmos Sci,35(1):81-94.(in Chinese).
赵玉春,李泽椿,王叶红,等,2008.2006年6月5-8日梅雨锋上中尺度对流系统引发福建北部暴雨的诊断分析[J].大气科学,32(2):598-614.Zhao Y C,Li Z C,Wang Y H,et al.,2008.Diagnosing analysis of heavy rain in northern Fujian province triggered by mesoscale convective systems along the Meiyu front during 5-8 June 2006[J].Chin J Atmos Sci,32(2):598-614.(in Chinese).
Chappell C F,1986.Quasi-stationary convective events[M].Boston:American Meteorological Society:289-309.
Chen G T J,Yu C C,1988.Study of low-level jet and extremely heavy rainfall over northern Taiwan in the Meiyu season[J].Mon Wea Rev,116:884-891.
Chen G T J,Wang C C,Liu S C S,2003.Potential vorticity diagnostics of a Meiyu front case[J].Mon Wea Rev,131:2680-2696.
Ding Y H,1992.Summer monsoon rainfalls in China[J].J Meteor Soc Japan,70:373-396.
Ding Y H,Chan J C,2005.The East Asian summer monsoon:an overview[J].Meteorol Atmos Phys,89:117-142.
丁治英,王爽,高松,2017.一次华南双雨带暴雨中的位涡演变与雨带间的相互作用[J].大气科学学报,40(5):653-662.Ding Z Y,Wang S,Gao S,2017.Potential vorticity evolution of a double rainbands storm in South China and interactions between the rain-bands[J].Trans Atmos Sci,40(5):653-662.(in Chinese).
Doswell C A,Brooks H E,Maddox R A,1996.Flash flood forecasting:an ingredients-based methodology[J].Wea Forecasting,11:560-581.
高守亭,孙建华,崔晓鹏,2008.暴雨中尺度系统数值模拟与动力诊断研究[J].大气科学,32(4):854-866.Gao S T,Sun J H,Cui X P,2008.Numerical simulation and dynamic analysis of mesoscale torrential rain systems[J].Chin J Atmos Sci,32(4):854-866.(in Chinese).
何斌,何锋,范晓红,等,2013.一次长江中下游梅雨锋暴雨过程的诊断分析[J].高原气象,32(4):1074-1083.He B,He F,Fan X H,et al.,2013.Diagnostic analysis on a meiyu front rainstorm process in Mid-and Low-reaches of Yangtze River[J].Plateau Meteor,32(4):1074-1083.(in Chinese).
鞠永茂,王汉杰,钟中,等,2008.一次梅雨锋暴雨云物理特征的数值模拟研究[J].气象学报,66(3):381-395.Ju Y M,Wang H J,Zhong Z,et al.,2008.A simulation study on the characteristics of cloud microphysics of rain storm in a Meiyu front[J].Acta Meteorlogica Sinica,66(3):381-395.(in Chinese).
Luo Y L,Gong Y,Zhang D L,2014.Initiation and organizational modes of an extreme-rain-producing mesoscale convective system along a Mei-Yu front in East China[J].Mon Wea Rev,142(1):203-221.
苗春生,刘春,王坚红,等,2017a.FY-3A水汽资料在江淮梅雨强降水系统湿动力诊断中的应用[J].大气科学学报,40(1):36-47.Miao C S,Liu C,Wang J H,et al.,2017.Application of moisture data from the FY-3A satellite in moisture-dynamic diagnosis of Meiyu heavy precipitation systems over the Jianghuai Valley[J].Trans Atmos Sci,40(1):36-47.(in Chinese).
苗春生,吴琼,王坚红,等,2017b.淮河流域大别山地形对梅雨期暴雨低涡影响的模拟研究[J].大气科学学报,40(4):485-495.Miao C S,Wu Q,Wang J H,et al.,2015.Comparison of dry-cold intrusion in north and south heavy rainfall zones during Meiyu front rainstorms in ChangjiangHuaihe valleys[J].Trans Atmos Sci,38(1):76-84.(in Chinese).
闵锦忠,张申,杨婷,2018.一次梅雨锋暴雨发生发展机制的诊断与模拟[J].大气科学学报,41(2):155-166.Min J Z,Zhang S Y,Yang T,2018.Diagnosing analysis and numberical simulation of formation and development mechamism of a rainstorm associated with Meiyu front[J].Trans Atmos Sci,41(2):155-166.(in Chinese).
Schumacher R S,Johnson R H,2005.Organization and environmental properties of extreme-rain-producing mesoscale convective systems[J].Mon Wea Rev,133:961-976.
Schumacher R S,Johnson R H,2006.Characteristics of U.S.extreme rain events during 1999-2003[J].Wea Forecasting,21(1):69-85.
孙建华,赵思雄,2002.华南“94·6”特大暴雨的中尺度对流系统及其环境场研究Ⅰ.引发暴雨的β中尺度对流系统的数值模拟研究[J].大气科学,26(4):541-557.Sun J H,Zhao S X,2002.A Study of mesoscale convective systems and its environmental fields during the June 1994 record heavy rainfall of South China Part I:a numerical simulation study of meso-βconvective system inducing heavy rainfall[J].Chin J Atmos Sci,26(4):541-557.(in Chinese).
陶诗言,张小玲,张顺利,2004.长江流域梅雨锋暴雨灾害研究[M].北京:气象出版社.Tao S Y,Zhang X L,Zhang S L,2004.Study of Meiyu rainstorm disaster over Yangtze River[M].Beijing:China Meterological Press.(in Chinese).
Wang H,Luo Y L,Jou B J D,2014.Initiation,maintence,and properties of convection in an extreme rainfall event during SCMREX:observational analysis[J].J Geophys Res,119:13206-13232.
王晓芳,胡伯威,李红莉,等,2011.梅雨期一个伴有前导层状降水对流线的结构特征[J].高原气象,30(4):1052-1066.Wang X F,Hu B W,Li H L,et al.,2011.Stream structure of a convective line with leading stratiform precipitation during Meiyu period[J].Plateau Meteor,30(4):1052-1066.(in Chinese).
尹洁,郑婧,张瑛,等,2011.一次梅雨锋特大暴雨过程分析及数值模拟[J].气象,37(7):827-837.Yin J,Zheng J,Zhang Y,et al.,2011.Analysis and numerical simulation of a heavy rainfall event along the Meiyu front[J].Meteor Mon,37(7):827-837.(in Chinese).
Zhang M,Zhang D L,2012.Subkilometer simulation of a torrential-rain-producing mesoscale convective system in East China.Part I:model verification and convective organization[J].Mon Wea Rev,140:184-201.
张瑞萍,马旭林,盛文斌,等,2014.2011年6月江淮梅雨暴雨主要影响系统特征[J].大气科学学报,37(3):366-377.Zhang R P,Ma X L,Sheng W B,et al.,2014.Characteristics of the main influential system of Jianghuai Meiyu Storm in June 2011[J].Trans Atmos Sci,37(3):366-377.(in Chinese).
赵思雄,陶祖钰,孙建华,等,2004.长江流域梅雨锋暴雨机理的分析研究[M].北京:气象出版社.Zhao S X,Tao Z Z,Sun J H,et al.,2004.Analysis and research on Meiyu front rainstorm mechanism in Yangtze River Valley[M].Beijing:China Meterological Press.(in Chinese).
赵玉春,2011.梅雨锋对引发暴雨的中尺度对流系统发生发展影响的研究[J].大气科学,35(1):81-94.Zhao Y C,2011.Impacts of Meiyu front upon the initiation and development of mesoscale convection systems producing rainstorms[J].Chin J Atmos Sci,35(1):81-94.(in Chinese).
赵玉春,李泽椿,王叶红,等,2008.2006年6月5-8日梅雨锋上中尺度对流系统引发福建北部暴雨的诊断分析[J].大气科学,32(2):598-614.Zhao Y C,Li Z C,Wang Y H,et al.,2008.Diagnosing analysis of heavy rain in northern Fujian province triggered by mesoscale convective systems along the Meiyu front during 5-8 June 2006[J].Chin J Atmos Sci,32(2):598-614.(in Chinese).