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通讯作者:

王咏青,E-mail:yongqing@nuist.edu.cn

中文引用: 何丽华,王咏青,隆璘雪,等,2020.弱天气强迫下一次暖区MCSs发生发展研究[J].大气科学学报,43(5):810-823.

英文引用: He L H,Wang Y Q,Long L X,et al.,2020.Study of the occurrence and development of warm-sector MCSs for weak synoptic forcing[J].Trans Atmos Sci,43(5):810-823.doi:10.13878/j.cnki.dqkxxb.20191104002.(in Chinese).

参考文献 1
Bonner W D,1968.Climatology of the low level jet[J].Mon Wea Rev,96(12):833-850.
参考文献 2
Bryan G H,Fritsch M J,2000.Moist absolute instability:the sixth static stability state[J].Bull Amer Meteor Soc,81(6):1207-1230.
参考文献 3
Carbone R E,Tuttle J D,Ahijevych D,et al.,2002.Inferences of predictability associated with warm season precipitation episodes[J].J Atmos Sci,59(13):2033-2056.
参考文献 4
Charba J,1974.Application of gravity current model to analysis of squall-line gust front[J].Mon Wea Rev,102(2):140-156.
参考文献 5
陈明轩,高峰,孙娟珍,等,2016.基于VDRAS的快速更新雷达四维变分分析系统[J].应用气象学报,27(3):257-272.Chen M X,Gao F,Sun J Z,et al.,2016.An analysis system using rapid-updating 4-D variational radar data assimilation based on VDRAS[J].J Appl Meteor Sci,27(3):257-272.(in Chinese).
参考文献 6
Chen S S,Frank W M,1993.A numerical study of the genesis of extratropical convective mesovortices.part Ⅰ:evolution and dynamics[J].J Atmos Sci,50(15):2401-2426.
参考文献 7
Chen S S,Houze R A,Mapes B E,1996.Multiscale variability of deep convection in relation to large-scale circulation in TOGA COARE[J].J Atmos Sci,53(10):1380-1409.
参考文献 8
Corfidi S F,2003.Cold pools and MCS propagation:forecasting the motion of downwind-developing MCSs[J].Wea Forecasting,18(6):997-1017.
参考文献 9
Corfidi S F,Meritt J H,Fritsch J M,1996.Predicting the movement of mesoscale convective complexes[J].Wea Forecasting,11(1):41-46.
参考文献 10
Craig Goff R,1976.Vertical structure of thunderstorm outflows[J].Mon Wea Rev,104(11):1429-1440.
参考文献 11
Davis C A,Weisman M L,1994.Balanced dynamics of mesoscale vortices produced in simulated convective systems[J].J Atmos Sci,51(14):2005-2030.
参考文献 12
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 rainbands[J].Trans Atmos Sci,40(5):653-662.(in Chinese).
参考文献 13
Doswell C A,Brooks H E,Maddox R A,1996.Flash flood forecasting:an ingredients-based methodology[J].Wea Forecast,11(4):560-581.
参考文献 14
Fritsch J M,Forbes G S,2001.Mesoscale convective systems[J].Meteor Mon,28:323-357.
参考文献 15
Fritsch J M,Murphy J D,Kain J S,1994.Warm core vortex amplification over land[J].J Atmos Sci,51(13):1780-1807.
参考文献 16
耿建军,肖现,王迎春,等,2012.变分多普勒雷达分析系统对北京一次强降水过程的短时预报能力初探[J].大气科学学报,35(6):730-736.Geng J J,Xiao X,Wang Y C,et al.,2012.A preliminary exploration on the nowcasting ability of VDRAS in a rainstorm case in Beijing[J].Trans Atmos Sci,35(6):730-736.(in Chinese).
参考文献 17
何立富,陈涛,周庆亮,等,2007.北京“7.10” 暴雨β-中尺度对流系统分析[J].应用气象学报,18(5):655-665.He L F,Chen T,Zhou Q L,et al.,2007.The meso-β scale convective system of a heavy rain event on July 10,2004 in Beijing[J].J Appl Meteor Sci,18(5):655-665.(in Chinese).
参考文献 18
侯淑梅,闵锦忠,王改利,等,2020.传播运动在对流风暴合并过程中的作用[J].大气科学学报,43(2):347-357.Hou S M,Min J Z,Wang G L,et al.,2020.Effect of propagation moving on the convective storm mergence process[J].Trans Atmos Sci,43(2):347-357.(in Chinese).
参考文献 19
Houze R A,2014.Atmospheric dynamics[M]//International Geophysics.Amsterdam:Elsevier:25-46.
参考文献 20
Houze R A,Rutledge S A,Biggerstaff M I,et al.,1989.Interpretation of Doppler weather radar displays of midlatitude mesoscale convective systems[J].Bull Am Meteor Soc,70(6):608-619.
参考文献 21
Jirak I L,Cotton W R,McAnelly R L,2003.Satellite and radar survey of mesoscale convective system development[J].Mon Wea Rev,131(10):2428-2449.
参考文献 22
Lane T P,Sharman R,Trier S B,et al.,2012.Recent advances in the understanding of near-cloud turbulence[J].Bull Amer Meteor Soc,93(4):499-515.
参考文献 23
Lemone M A,1983.Momentum transport by a line of cumulonimbus[J].J Atmos Sci,40(7):1815-1834.
参考文献 24
Liang Z M,Liu Y,Yin J F,et al.,2019.A case study of the effects of a synoptic situation on the motion and development of warm-sector mesoscale convective systems over South China[J].Asia-Pac J Atmos Sci,55(2):255-268.
参考文献 25
Meng Z Y,Zhang F Q,Markowski P,et al.,2012.A modeling study on the development of a bowing structure and associated rear inflow within a squall line over South China[J].J Atmos Sci,69(4):1182-1207.
参考文献 26
苗春生,吴琼,王坚红,等,2017.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.,2017.Simulation study on effects of terrain of Dabie Mountains on rainstorm cyclone in Huaihe River Basin during Meiyu period[J].Trans Atmos Sci,40(4):485-495.(in Chinese).
参考文献 27
Moncrieff M W,Klinker E,1997.Organized convective systems in the tropical western Pacific as a process in general circulation models:a toga coare case-study[J].Quart J Roy Meteor Soc,123(540):805-827.
参考文献 28
Moore J T,Pappas C H,Glass F H,1993.Propagation characteristics of mesoscale convective systems.Preprints[C]//17th conf on severe local storms.St.Louis,MO.
参考文献 29
Nesbitt S W,Zipser E J,Cecil D J,2000.A census of precipitation features in the tropics using TRMM:Radar,ice scattering,and lightning observations[J].J Climate,13(23):4087-4106.
参考文献 30
Parker M D,Johnson R H,2000.Organizational modes of midlatitude mesoscale convective systems[J].Mon Wea Rev,128(10):3413-3436.
参考文献 31
Purdom J F W,1973.Picture of the month:Meso-highs and satellite imagery[J].Mon Wea Rev,101(2):180-181.
参考文献 32
Rotunno R,Klemp J B,Weisman M L,1988.A theory for strong,long-lived squall lines[J].J Atmos Sci,45(3):463-485.
参考文献 33
Schumacher C,Houze R A,2003.Stratiform rain in the tropics as seen by the TRMM precipitation radar[J].J Climate,16(11):1739-1756.
参考文献 34
Schumacher R S,Johnson R H,2005.Organization and environmental properties of extreme-rain-producing mesoscale convective systems[J].Mon Wea Rev,133(4):961-976.
参考文献 35
Skamarock W C,Weisman M L,Klemp J B,1994.Three-dimensional evolution of simulated long-lived squall lines[J].J Atmos Sci,51(17):2563-2584.
参考文献 36
孙继松,何娜,郭锐,等,2013.多单体雷暴的形变与列车效应传播机制[J].大气科学,37(1):137-148.Sun J S,He N,Guo R,et al.,2013.The configuration change and train effect mechanism of multi-cell storms[J].Chin J Atmos Sci,37(1):137-148.(in Chinese).
参考文献 37
王福侠,俞小鼎,裴宇杰,等,2016.河北省雷暴大风的雷达回波特征及预报关键点[J].应用气象学报,27(3):342-351.Wang F X,Yu X D,Pei Y J,et al.,2016.Radar echo characteristics of thunderstorm gales and forecast key points in Hebei Province[J].J Appl Meteor Sci,27(3):342-351.(in Chinese).
参考文献 38
王丽荣,李姣,张素云,等,2019.雷达对冰雹灾害落区的跟踪及鉴定[J].灾害学,34(3):66-70.Wang L R,Li J,Zhang S Y,et al.,2019.Hail disaster area tracing and identification by radar products[J].J Catastrophology,34(3):66-70.(in Chinese).
参考文献 39
王晓芳,崔春光,2011.暴雨中尺度对流系统研究的若干进展[J].暴雨灾害,30(2):97-106.Wang X F,Cui C G,2011.A number of advances of the research on heavy rain mesoscale convective systems[J].Torrential Rain Disasters,30(2):97-106.(in Chinese).
参考文献 40
王秀明,俞小鼎,周小刚,2015.中国东北龙卷研究:环境特征分析[J].气象学报,73(3):425-441.Wang X M,Yu X D,Zhou X G,2015.Study of Northeast China torandoes:the environmental characteristics[J].Acta Meteorol Sin,73(3):425-441.(in Chinese).
参考文献 41
王雪,林永辉,刘善峰,2019.江南一次持续性暴雨过程中线状中尺度对流系统模态转换机理研究[J].大气科学学报,42(1):138-150.Wang X,Lin Y H,Liu S F,2019.The mechanism of transition of linear mesoscale convection system mode in a continuous rainstorm process in the Jiangnan region[J].J Nanjing Inst Meteor,42(1):138-150.(in Chinese).
参考文献 42
王易,徐芬,吴海英,2019.一次致雹超级单体结构特征分析[J].大气科学学报,42(4):612-620.Wang Y,Xu F,Wu H Y,2019.Structure characteristics analysis of a supercell hailstorm[J].Trans Atmos Sci,42(4):612-620.(in Chinese).
参考文献 43
Webster P J,Bradley E F,Fairall J S,et al.,2002.The JASMINE pilot study[J].Bull Amer Meteor Soc,83(11):1603-1630.
参考文献 44
Williams M,Houze R A,1987.Satellite-observed characteristics of winter monsoon cloud clusters[J].Mon Wea Rev,115(2):505-519.
参考文献 45
于波,荆浩,孙继松,等,2017.北京夏季一次罕见偏南大风天气的成因分析[J].高原气象,36(6):1674-1681.Yu B,Jing H,Sun J S,et al.,2017.The analysis on an infrequent southerly gust of Beijing in summer[J].Plateau Meteor,36(6):1674-1681.(in Chinese).
参考文献 46
俞小鼎,周小刚,王秀明,2012.雷暴与强对流临近天气预报技术进展[J].气象学报,70(3):311-337.Yu X D,Zhou X G,Wang X M,2012.The advances in the nowcasting techniques on thunderstorms and severe convection[J].Acta Meteorol Sin,70(3):311-337.(in Chinese).
参考文献 47
Yuter S E,Houze Jr R A,1998.The natural variability of precipitating clouds over the western Pacific warm pool[J].Quart J Roy Meteor Soc,124(545):53-99.
参考文献 48
Zhang D L,1992.The formation of a cooling-induced mesovortex in the trailing stratiform region of a midlatitude squall line[J].Mon Wea Rev,120(12):2763-2785.
参考文献 49
张家国,周金莲,谌伟,等,2015.大别山西侧极端降水中尺度对流系统结构与传播特征[J].气象学报,73(2):291-304.Zhang J G,Zhou J L,Chen W,et al.,2015.The structure and propagation characteristics of the extreme-rain-producing MCS on the west side of Dabie Mountain[J].Acta Meteorol Sin,73(2):291-304.(in Chinese).
参考文献 50
张艳霞,蒙伟光,戴光丰,等,2015.台风“凡亚比”登陆过程中暴雨MCSs演变及形成机理[J].热带气象学报,31(4):433-443.Zhang Y X,Meng W G,Dai G F,et al.,2015.The evolution and formation mechanism of rainstorms mcss during typhoon fnanpi landing[J].J Trop Meteor,31(4):433-443.(in Chinese).
参考文献 51
赵珊珊,高歌,黄大鹏,等,2017.2004—2013年中国气象灾害损失特征分析[J].气象与环境学报,33(1):101-107.Zhao S S,Gao G,Huang D P,et al.,2017.Characteristics of meteorological disaster losses in China from 2004 to 2013[J].J Meteor Environ,33(1):101-107.(in Chinese).
参考文献 52
赵宇,裴昌春,赵光平,等,2018.梅雨锋暴雨中尺度对流系统的组织特征和触发条件分析[J].大气科学学报,41(6):807-818.Zhao Y,Pei C C,Zhao G P,et al.,2018.Analysis of organization modes and initiation conditions of a heavy-rain-producing mesoscale convective system along a Meiyu front[J].Trans Atmos Sci,41(6):807-818.(in Chinese).
参考文献 53
Zipser E J,1977.Mesoscale and convective-scale downdrafts as distinct components of squall-line structure[J].Mon Wea Rev,105(12):15681589.
目录contents

    摘要

    2017年7月21日上午,石家庄地区出现了一次局地暴雨过程,强降水主要集中在石家庄市区及其东部、北部,数值预报产品和主观预报均漏报了此次暴雨过程。本文利用地面加密自动站、多普勒雷达观测资料、雷达风廓线、多普勒雷达四维变分分析系统(VDRAS)以及NCEP再分析资料,分析了造成本次局地暴雨的中尺度对流系统(Mesoseale Convective Systems,MCSs)的触发机制,讨论了该系统的传播方向和影响整体运动的主要因子。结果表明:1)本次强降水发生前受“副高”588 dagpm线控制,降水区高温、高湿,为降水的发生积聚了大量不稳定能量。由于太行山在石家庄附近由东北-西南走向转为西北-东南走向,东北气流在此处逆转为西西北气流,从而在山前形成东北风和西西北风的辐合线;河北东北部秦皇岛、唐山地区因强降水形成较强的雷暴高压、冷池,雷暴高压产生的气压梯度力影响东北风逐渐加强,加强的东北风气流引导冷池呈舌状逐渐西南方向移动到石家庄北部地区,在前述辐合线附近形成低层辐合、中层辐散的不稳定层结,与西部太行山迎风坡对东北气流的强迫抬升共同作用,触发了不稳定能量的释放。2)本次过程前期雷暴在发展加强过程中,MCSs降水形成的雷暴冷出流东北方向移动,移速缓慢,在与环境东北气流辐合的区域,不断有新的雷暴触发,使得雷暴向东北方向传播,此阶段风暴承载层平均风(即MCSs的平移方向)风速较小,MCSs的移动平流不明显,以“后向传播”为主,系统稳定少动,表现为“准静止状态”;随着风暴承载层平均风风速的增加,MCSs的移动方向可以通过Corfidi矢量法,由低空急流的反向矢量和1.5 km以上(850~300 hPa)的平均风速矢量合成得到,且此阶段MCSs自身冷池的移动方向与风暴承载层平均风(西北风)密切相关,对应的雷暴冷出流东南方向移动,使得西北偏冷风冷池出流与环境东南偏暖风形成辐合,在MCSs前部不断有雷暴单体新生,传播方向与平流方向一致,系统“快速”东南方向移动。

    Abstract

    On the morning of July 21,2017,a localized rainstorm event occurred in Shijiazhuang,with the heavy rain mainly concentrating in its urban area,eastern and northern parts,which was omitted by both numerical and subjective forecasts.In this paper,the triggering mechanisms of the mesoscale convective system(MCS) causing this rainstorm,the propagation direction of the system and the main factors affecting the overall movement were analyzed by using the intensified surface observation data,Doppler radar data,radar wind profile,the four-dimensional variational Doppler radar analysis system(VDRAS) and NCEP reanalysis data.The results show that:1)Before the heavy precipitation occurring,a large amount of unstable energy was accumulated because of the high temperature and high humidity in this area.The surface airflow was turned by Taihang Mountain in the vicinity of Shijiazhuang,forming the shear line of northeast wind and west-northwest wind in front of the mountain.The strong thunderstorm high and cold pool was formed by the heavy precipitation in Qinhuangdao and Tangshan areas.The pressure gradient force generated by the thunderstorm high strengthened the northeast wind,which guiding the cold pool to gradually move southwest in a tongue shape to the north of Shijiazhuang area.In the vicinity of the aforementioned shear line,an unstable stratification of low-level convergence and middle-level divergence was formed,which was combined with the topographic forced uplift of the windward slope triggering the unstable energy release.2)During the development and strengthening of thunderstorm,the cold outflow formed by the precipitation of MCS moved slowly in the northeast direction.In the area where the northeast airflow was converged,new thunderstorms were constantly triggered,which made thunderstorms spread northeast.At this stage,the average wind speed of the storm bearing layer(ie,the translation direction of the MCS) was small,the system was stable and less moving,mainly in the form of “backward propagation”,which was shown as “quasi-static state”.With the increase of the average wind speed in the storm bearing layer,the moving direction of the MCS could be synthesized from the reverse vector of the low-level jet and the average wind vector above 1.5 Km(between 850 and 300 hPa layers).At this stage,the moving direction of the cold pool was closely related to the average wind in the storm bearing layer,causing the thunderstorm cold outflow moving southeast.The northwest cold outflow of the cold pool formed the convergence with the southeast warm environmental flow,leading to the constantly emerging thunderstorm cells in the front of the MCS.The propagation direction was consistent with the advection direction,and the system moved “fast” to the southeast.

    关键词

    暖区暴雨MCSs冷池地形平流与传播

  • 中尺度对流系统(Mesoseale Convective Systems,MCSs)是一组有组织的雷暴,在至少一个方向上产生一个100 km或更远的连续降水区。该系统以塔状对流云降水开始,发展为对流云-层状云耦合垂直环流增长,最终以层状云降水结束,其持续时间一般可达几个小时,组织性较强的甚至可持续十几个小时。Houze(2014)用云图特征将MCSs描述为包含对流核的云结构,它沿某一方向伸展大约100 km,形成一普遍降水区域。Schumacher et al.(2005)用雷达反射率因子定义MCSs,即对流系统的反射率因子大于等于40 dBz区域,其范围大于100 km,持续时间为3~24 h。所有MCSs都可能导致暴雨(何立富等,2007,张艳霞等,2015;丁治英等,2017;苗春生等,2017;赵宇等,2018;王雪等,2019),有组织的MCSs还可能导致恶劣天气,包括破坏性地面大风(王福侠等,2016;于波等,2017;侯淑梅等,2020)、冰雹(王丽荣等,2019;王易等,2019)和偶尔的龙卷风(Meng et al.,2012;王秀明等,2015)。此外,它们也是湍流的来源,对航空飞行造成危害(Lane et al.,2012)。MCSs是强对流天气的直接制造者(王晓芳和崔春光,2011;俞小鼎等,2012;赵珊珊等,2017)。

  • MCSs一般可分为以下几类:非飑线对流簇、中尺度对流复合体、飑线或飑线簇、弓形回波。Jirak et al.(2003)使用卫星资料,根据尺度大小和组织形状将MCSs分为四类,即中尺度对流复合体(Mesoscale Convective Complex,MCC),持续拉长状的对流系统(PECS),β中尺度对流复合体(Meso-βscale MCC,MβCC)和β中尺度持续拉长状对流系统(Meso-βscale PECS,MβECS)。Parker et al.(2000)应用雷达资料,根据层状区相对于对流区的位置,将美国中部线状中尺度对流系统(MCSs)分为三类:尾部层状云(Trainling stratiform)、先导层状云(Leading stratiform)、平行层状云(Parallel stratiform),并给出了这3类MCSs的统计特征。

  • 多年来,国内外气象学者对MCSs的组织结构以及MCSs与大尺度环流的相互作用,从以下几个方面进行了研究:1)MCS中上升及下沉气流结构及概念模型(Zipser,1977;Houze et al.,1989;Moncrieff and Klinker,1997;Bryan and Fritsch,2000)。2)MCSs中层的中尺度对流涡旋(MCV)形成机制(Zhang,1992;Chen and Frank,1993;Skamarock et al.,1994)。3)MCSs的组织、移动及传播模式(Rotunno et al.,1988;Fritsch et al.,1994;Corfidi et al.,1996;Doswell et al.,1996;Fritsch and Forbes,2001;Carbone et al.,2002)。4)MCSs的生命史及尺度的影响因子(Williams and Houze,1987;Chen et al.,1996;Webster et al.,2002)。5)MCSs通过动量和热量交换对大尺度环境的反馈(LeMone,1983;Yuter and Houze,1998)。6)MCSs的全球分布和影响(Nesbitt et al.,2000;Schumacher and Houze,2003)。上述综合研究表明:所有的MCSs最初都是通过环境风切变来组织的,风切变不仅决定了它们的组织模式,而且决定了中尺度上升气流和下沉气流的倾斜程度。最初,MCSs是对流塔,随后会形成冷池,一旦冷池形成,他们沿着自己的冷池进行组织,此时环境涡度和冷池涡度平衡;在成熟阶段,MCSs主要是层状降水,但仍然包含对流降水,特别是在其前缘;当冷池远离对流塔时,低层入流和冷池出流的辐合终止,于是MCSs将减弱消亡,在这个阶段,随着对流塔的消亡,降水主要是层状云。在长生命史、大型MCSs中,层状云区域的潜热释放和辐合会导致中尺度对流涡旋(MCV)的形成,新的对流在会在MCV内触发。

  • 尽管国内外学者对中尺度对流系统(MCSs)的分布、结构、发生发展移动特征及机制有了诸多认识,但目前MCSs仍然不能被大尺度模式明确描述,中尺度模式虽然具备了描述MCSs的能力,但预报效果并不理想(Davis and Weisman,1994)。总体而言,不论大尺度模式还是中尺度模式,对MCSs的预报能力非常有限,特别是对弱天气强迫下的强对流及暖区对流,几乎没有预报能力,对这类强天气的预报,预报员面临巨大的挑战。2017年7月21日上午,河北石家庄地区出现了一次局地暴雨过程,强降水主要集中在石家庄市区及其东部、北部,是一次典型的β中尺度雨带中的γ中尺度对流系统引发的大暴雨,造成了严重的城市内涝和交通拥堵。本次局地暴雨过程发生在副热带高压内,是弱天气强迫下的暖区暴雨,此前的数值预报、主观预报均漏报了此次暴雨过程。雷达分析表明,初始回波在石家庄西部的太行山山前突然产生,在原地快速发展增强并维持,2 h以后又迅速东移减弱消散,预报难度较大。那么本次MCSs的抬升触发机制是什么?发生发展移动的原因又是什么?本文将通过多普勒雷达、高空和地面加密自动站、风廓线雷达等高分辨率资料,利用变分多普勒雷达分析系统(VDRAS),深入剖析本次MCSs,重点讨论与冷池、地形有关的影响新单体生成的原因,以及最终影响系统整体运动的因子,从而提升短期潜势预报及短临预警的能力。

  • 1 资料与分析方法

  • 使用的资料包括

  • 首先通过对加密自动站雨量分析,了解和揭示了β中尺度雨团中的γ中尺度雨团的活动特点;其次利用常规天气图及1°×1° NCEP再分析格点资料分析了本次MCSs发生发展的天气尺度环流背景;通过对加密自动站多要素资料及高时空分辨率的多普勒雷达四维变分分析系统(VDRAS)资料分析了本次暖区暴雨的触发抬升机制,最后利用对加密自动站多要素资料、雷达反射率因子及风廓线雷达资料的分析,揭示了最终影响系统整体运动的关键因子。

  • 其中,多普勒雷达四维变分分析系统(Four Dimensional Variational Doppler Radar Analysis System,VDRAS),采用了四维变分资料同化技术、云尺度数值模式及其伴随模式,利用单部或多部多普勒雷达观测资料,反演对流尺度风暴的动力结构和微物理结构,包括三维风场、温度场、湿度场等(耿建军等,2012;孙继松等,2013;陈明轩等,2016)。

  • 2 过程概述

  • 2017年7月21日08—14时(北京时,下同),河北石家庄地区出现了一次区域性暴雨过程,有59个站次(含区域站,下同)降水超过50 mm,其中8个站次降水量超过100 mm,最大降水量石家庄藁城县张家庄站,为163 mm,其雨强达82.8 mm/h。本次局地暴雨过程从云图上分析是一次典型的MCSs过程,其主要特点是:1)持续时间短,雨强大。强降水维持4 h,最大降水中心强降水时段主要集中在11—12时,1 h最大降水量达88.5 mm,之后1 h降水量也超过60 mm;2)降水落区相对集中,中尺度特征明显(图1a)。

  • 短时强降水主要集中在石家庄市区及其东部、北部区域,大暴雨主要集中在两个中心,一个中心位于石家庄北部不足5 km范围内,另一个中心位于石家庄东北部地区,降水范围不足400 km2,由降水最强站逐5 min雨量演变(图1b)可见,5 min雨强呈多个峰值特征,有四个雨锋在5 mm/(5 min)以上,其中主峰雨强10.8 mm/(5 min),出现时间为11:35,是一次典型的β中尺度雨团中的γ中尺度对流系统引发的大暴雨过程。

  • 3 环境场特征分析

  • 本次强降水发生在西太平洋副热带高压(以下简称“副高”)588 dagpm副高线控制区。2017年7月20日20时500 hPa高空(图2a)上,588 dagpm线位于38°N附近,并不断北抬,高空槽位于我国东北地区到蒙古国东部一线,且不断东移。河北省东北部(秦皇岛附近)地区此时处于高空槽底部,副高外围588 dagpm与584 dagpm之间较平直的偏西气流中,在对流层低层850 hPa图(图2b)上,与500 hPa高空槽相配合的冷切变线位于吉林-辽宁-河北北部一线,河北省东北部(秦皇岛附近)地区位于切变线前部的西南急流区。受该高空槽底部弱冷空气及副高外围暖湿气流的共同影响,河北省东北部

  • 图.1 2017年7月21日08—14时过程雨量(a;单位:mm)和降水中心10:30—13:40逐5 min雨量(b;单位:mm)

  • Fig.1 The total precipitation at(a)08:00 BST—14:00 BST,and precipitation every 5 minutes in the rainfall center at(b)10:30 BST—13:40 BST on 21 July 2017(unit:mm)

  • 图.2 2017年7月20日20时500 hPa(a)、850 hPa(b),21日08时500 hPa(c)环流形势(蓝实:位势高度,单位:dagpm;风矢:风场;棕实:槽线;红双实线:切变线;红点:秦皇岛;橘点:石家庄)以及21日08时地面场(d)(蓝实:等压线,单位:hPa;红虚:≥28℃等温线,单位:℃)

  • Fig.2 The synoptic situations on(a)500 hPa,(b)850 hPa at 20:00 BST on 20 July 2017,and(c)500 hPa at 08:00 BST on 21 July 2017(blue solid line:geopotential height,unit:dagpm;wind arrow:wind;brown solid line:trough line;red double solid line:shear line;red dot:Qinhuangdao;orange dot Shijiazhuang),and near surface(d)at 08:00 BST on 21 July 2017(blue solid line:isobar,unit:hPa;red dotted line:isotherm≥28℃,unit:℃)

  • (秦皇岛附近)地区在21日凌晨03—05时出现强降水(图4a)。7月21日08时,500 hPa高度场(图2c)上,588 dagpm线已北抬至40°N附近,其北侧以偏西风为主,且风速较大,为16~18 m/s,不利于冷空气南下,河北中南部大部分地区都处于副热带高压控制,石家庄地区位于588 dagpm线以南的区域。地面图(图2d)上,21日08时气压场呈北高南低的形势,高压中心位于蒙古国东部地区,40°N附近(北京-天津北部一线)有一弱的冷锋,锋面南侧为东北风,河北省中南部地区气温较高,在28℃以上,石家庄地区附近的露点温度均在26℃及以上,说明石家庄地区的温湿条件非常有利于短时强降水等对流性天气发生。

  • 21日08时邢台(站号:53789,位置如图4a所示)探空资料显示(图3),湿层深厚(600 hPa以下),尤其是近地层872 hPa以下T-Td≤2℃,基本处于准饱和状态,对流凝结高度CCL较低,位于924 hPa,有利于短时强降水发生,886~850 hPa之间存在2℃的浅薄逆温层,有利于低层能量的积聚,K指数达到43℃,沙氏指数达-2.99℃,大气层结极不稳定。湿对流有效位能CAPE值高达1715.7 J·kg-1,尽管有对流抑制能量存在,但相对较小,仅为121.7 J·kg-1。0℃层高度高于460 hPa等压面,达5910 m,高度较高,说明暖云层厚度较厚,易出现热带型降水,降水效率较高。

  • 由物理量场分析(图略)表明,石家庄地区局地暴雨发生前,整层大气可降水量在70~78 mm,850 hPa比湿达到17 g/kg及以上,局地水汽十分充沛;850 hPa假相当位温高达361 K,暖湿气团强盛。

  • 总之,河北中南部在副高控制下,具备了较好的水汽条件、热力条件和对流不稳定条件。一旦有了抬升机制,便可触发对流,释放不稳定能量。

  • 图.3 2017年7月21日08时邢台探空站T-logp分布

  • Fig.3 T-logp chart at Xingtai sounding station at 08:00 BST on July 21,2017

  • 4 远距离冷池、地形与对流的触发

  • 4.1 远距离冷池出流

  • 冷池是雷暴系统内因降水粒子在下降过程中由于融化、蒸发等过程导致气块降温,下降气块在近地层堆积而形成冷空气堆。2017年7月21日02—05时,在河北省东北部的唐山、秦皇岛地区出现短时强降水(图4a),区域站最大降水量出现在秦皇岛北戴河区的海滨站,150.6 mm。受强降水影响,秦皇岛和唐山地区地面气温明显下降,由21日05时地面自动站3 h变温(图4b)显示,该冷池中心最大降温强度达-7.9℃,形成雷暴冷池,温度的快速下降导致当地气压快速升高,21日05时地面自动站3 h变压场最大的气压增值为4.9 hPa。

  • 此时地面气压场为北高南低的形势(图2d),秦皇岛、唐山地区位于为高压底部,为东北风,形成东北风冷池出流,中心最大风速达20 m/s,冷池高压边界处的风速也达12~18 m/s(图4b)。在雷暴高压产生的气压梯度力影响下,东北风冷池出流逐渐西南方向移动。冷空气运动在很大程度上是由动量传递决定的。由图4c—e分析可知,在东北风冷池出流引导下,河北省东北部(秦皇岛、唐山)地区的雷暴冷池向西南方向逐渐被拉伸,负变温场的移动与地面加密自动站观测到的东北风大风速区相配合。当冷池边界(变温0℃线)被拉长时,其某些部分必然会垂直于东北风,而其他部分则会平行于东北风(Corfidi,2003)。垂直于东北风的边界部分随着时间的推移而向东北风下游(西南方向)推进。

  • 冷中心的外围,是一个温度的不连续边界,具有低层辐合和上升的特点(Purdom,1973;Charba,1974;Craig,1976)。因此,冷池的外围边界通常新对流单体容易生成。当08时前后冷池前缘边界向西南(东北风下风)方向移动到石家庄北部地区,受太行山地形阻挡,负变温区域前沿西南方向移速减缓(4e—f),冷暖边界(变温0℃线为边界)有一个较长时间维持的过程,从而触发了本次强对流的发展。

  • 4.2 地形强迫

  • 河北省地形复杂,北部为燕山山脉,西侧为太行山山脉。石家庄地区地势大体是西高东低,地形复杂,其西侧太行山脉由东北-西南走向转为西北-东南走向,为向东开口的“人”字形地形结构。21日05—09时(图4b—f)地面自动站东北风气流沿太行山东麓,受太行山“人”字形地形结构强迫,东北气流在石家庄地区沿山脉走向逆转为西西北气流,从而在山前形成东北风和西西北风的辐合线(图4d—f),为触发本次MCSs生成发展的一个关键因素。且该辐合线长时间维持,降水回波不断在辐合线附近生成加强。

  • 由图4地形与风场配置可知,在本次MCSs触发过程中,石家庄西南侧西北东南走向的太行山地形,与东北风气流基本成正交,此处太行山高约800 m,近地层的东北风气流受太行山体迎风坡强迫抬升作用,加剧了大气层结的不稳定性。利用高时空分辨率的多普勒雷达四维变分分析系统(VDRAS)资料反演的风场垂直分布(图略)可以看出,东北风气流在08:42开始在太行山地形迎风坡山前倾斜抬升,随着东北风的逐渐加强,09:18左右在1000~3500 m高处,气流基本处于垂直上升状态。

  • 为了更清楚地研究分析本次MCSs的触发机制,本文使用高时空分辨率的多普勒雷达四维变分分析系统(VDRAS)资料对其进行分析。降水发生前(图5a),利用VDRAS资料反演的187.5 m高度扰动温度场与散度场表明,21日08:12,负扰动温度的前缘,以及地面自动站风场辐合线(红色双线)相配合,中心散度为-10×10-5 s-1(图5a),沿114.3E垂直剖面图(图5c)可以很明显地看出,该辐合区只位于1000 m以下很低的层次,其最大值仅仅出现在500 m以下的近地面层,该辐合区的产生与地面自动站风场辐合线以及冷中心前缘的温度不连续面的存在有关。与该中心配合的2062.5 m高度上为7×10-5 s-1(图5c)的辐散中心,从而形成近地层辐

  • 图.4 21日05:00 3 h降水量(a;单位:mm),21日05:00—09:00国家级地面自动站小时极大风风场(风矢)和变温场(圆点,单位:℃)以及05:00时3 h变温(b);06:00—09:00逐小时变温(c—f;红实线:地面辐合线;阴影:地形;+:石家庄)

  • Fig.4 The precipitation in three hours(a,unit:mm) at 05:00 SBT,hourly maximum winds(wind arrow) of the National Automatic Weather Station and varying temperature(a,dot,unit:℃;three hours temperature change at(b)05:00 SBT;(c—f)hourly temperature change at 06:00 SBT—09:00 SBT(red solid line:surface convergence line;shadow:terrain;+:Shijiazhuang) on July 21,2017

  • 合,中层辐散的有利于对流发展的动力场(图5c红框内),与低层辐合、中层辐散相配合的,上升速度区发展高度达4500 m,中心位于1500 m,中心最大值10×10-2 m/s(图5c),地面辐合线附近8:12雷达回波图上能分析出27.5 dBZ的很弱的分散的对流单体生成。随着地面自动站风场辐合线的维持,以及随东北风西南下的冷中心前缘的稳定少动,低层辐合中层辐散的有利形势一直存在且逐渐加强,中

  • 图.5 08:12 VDRAS资料反演187.5 m扰动温度场(a;阴影,℃)、辐合区(红色实线,10-5 s-1)和地面加密自动站实况风场(风矢);(b)08:30雷达反射率因子(阴影,dBZ)与实况风场(风矢);08:12(c)和09:00(d)沿114.3°E垂直剖面的上升速度(黑色实线,10-2m·s-1)和散度(阴影,10-5 s-1)(红色双实线:地面辐合线)

  • Fig.5 187.5 m perturbation temperature(shadow,℃),convergence area(red solid line,10-5 s-1) inverted from VDRAS data and winds(wind arrow) of dense Automatic Weather Station at(a)08:12 BST;Radar reflectivity factor(shadow:dBZ) and winds(wind arrow) of Automatic Weather Station at(b)08:30 BST;vertical motion(black solid line,10-2m·s-1) and divergence(shadow,10-5s-1) inverted from VDRAS data along the section of 114.3°E at(c)08:12 BST and(d)09:00 BST(red double solid line:surface convergence line)

  • γ尺度对流初生回波在地面辐合线偏冷一侧,呈多个不规则的片絮状回波,沿辐合线西北东南方向带状排列(图5b),09时(图5d红框内)辐合中心虽然仍只是存在于1000 m以下,但中心值增强为-14×10-5 s-1,与该动力抬升区域配合的最大上升中心速度也增加至18×10-2 m/s,此时多普勒雷达回波可以看到很明显的对流单体逐渐发展加强,其回波强度中心已加强为52.5 dBZ。

  • 综合以上分析得知,河北东北部秦皇岛、唐山地区因强降水形成较强的雷暴高压、冷池,雷暴高压产生的气压梯度力影响东北风逐渐加强,加强的东北风气流引导冷池呈舌状逐渐西南方向移动到石家庄北部地区。太行山东麓的东北风气流受太行山地形强迫发生转向,形成东北风与西西北风的辐合,并长时间维持。东北风气流在地面风场辐合及冷池前缘温度不连续面附近形成近地面的辐合,并受太行山地形迎风坡强迫抬升作用影响形成上升气流,触发了本次雷暴的发生。

  • 5 MCSs移动特征

  • Moore et al.(1993)研究表明MCSs在何处发生前向传播、后向传播和准平稳情况,除与850~300 hPa平均风有关以外,还与最大对流有效势能、锋面边界、850 hPa等效位温脊线、300 hPa高空急流和南侧LLJ等天气条件有关。Liang et al.(2019)认为低层垂直风切变的增强,是造成华南地区MCSs突然转向运动的关键因素。2017年7月21日08—14时石家庄多普雷雷达回波图上MCSs发展、移动的特征发现,08:00—10:42这一时间段是本次过程MCSs初生和发展加强的阶段,在该阶段雷达回波处于“准静止”状态,故把该阶段定义为本次过程的第一阶段准静止阶段。10:42—14:00雷暴发展成熟,快速东移过程中逐渐减弱消亡,故把该阶段定义为第二阶段快速东移阶段。

  • 本次过程中,导致不同阶段MCSs运动特征的关键因素有哪些?非常值得深入研究。Corfidi et al.(1996),利用低空急流来估计风暴传播的方向和速度,以预测MCSs中尺度核心或“质心”的短期(3~6 h)运动。预报质心运动:1)一个矢量,它代表平均云层风(“云层”为850~300 hPa层);2)单体平流,一个矢量代表风暴传播,即新的单体发展,大小相等,但与低层急流相反。在实践中,850 hPa风被用来近似低空急流。按照Bonner(1968)的规定,在垂直方向没有明显的低空风速最大值的情况下,通常使用最低1.5 km的最强风。上述方法适用于任何类型的环境风场,只需了解850 hPa和平均云层风。

  • 下面将具体分析本次过程中MCSs的移动,并应用上述方法预测MCSs整体运动,以期分析结果能对预报员在实际业务中对MCSs运动的外推有所帮助。

  • 5.1 准静止阶段

  • 1.5°仰角雷达回波反射率因子显示:在对流系统的初生阶段(08:30,图5b),多个片絮状γ中尺度对流单体回波沿地面辐合线西北东南向带状分布,9:00—10:42中γ尺度回波单体在原地(地面辐合线附近)发展加强,并伴有单体合并及新生。中尺度对流系统回波主体位于地面辐合线附近,最强回波中心达57.5 dBZ,从回波垂直结构来看(图略),强回波质心(反射率因子≥45 dBZ)分布在5 km以及下,低于0℃层高度(5910 m)的暖层云,说明大的反射率因子主要由液态雨滴产生,降水效率较高,09:10—10:00降水区10 min雨强一直保持在≥17.2 mm的高效率降水(非同一个站点),其中09:20—09:30自动站10 min雨强高达21.1 mm,从这2 h的小时雨强来看,10:00和11:00两个时次的最大小时雨强分别为91.3 mm·h-1和73.7 mm·h-1,由此分析可知,在本次过程初期,对流发展旺盛,其十分钟雨强和小时雨强都非常大。伴随着强降水的持续,其雷暴冷池周围的外泄气流与环境场的不连续线即冷出流边界(张家国等,2015)越发明显。Corfidi(2003)指出,在相对于MCSs出流边界的环境低层流入最大的地方,最容易产生新的对流单体。这是因为相对流入较强的地区也将是辐合的最大区域。由地面自动站风场分析可知,东北风由6 m/s(图6a)增加至8 m/s(图6b)。在此期间,当MCSs受西侧太行山地形阻挡而形成西北偏西的冷池出流与其东北侧逐渐加强的东北风入流形成辐合区,并与第5节中分析的地面辐合线叠加且较长时间维持(图7b),多普勒雷达回波反射率因子图上表现为:MCSs东北侧不断有新单体生成和发展(图6b),MCSs向东北方向逆风传播。分析石家庄风廓线雷达资料(图8)可知,在08:00—10:42期间,石家庄站上空1.5~5 km高度的偏西径向风风速很小,更直观地说明雷暴移动的引导气流相对较弱。与之相适应,雷暴主体沿引导气流方向移动缓慢(图6a、b),说明MCSs在这一阶段的移动平流运动不明显,其移动特征以传播为主,系统处于准静止状态。

  • 5.2 快速东移阶段

  • Corfidi(2003)认为,中尺度对流系统的传播受对流有效位能、对流抑制能量、雷暴出流边界等多因素影响。一般而言,冷池的移动方向与风暴承载层平均风即MCSs的平移方向有关。石家庄风廓线雷达资料(图8)显示,1.5 km以上风暴承载层偏西径向风风速增加明显,这从一个侧面说明此时间段内风暴引导气流明显增强。

  • 从多普勒雷达反射率因子11—12时的逐6 min回波演变分析可知,图6b中在“准静止阶段”长时间“稳定少动”的强降水对流回波在原地逐渐减弱消亡,在其东南侧有新的中尺度对流单体生成并发展加强,11时雷达强回波东南向移速加快,并表现为呈东北西南向带状分布(图6c),此时10 min最大雨强为22.8 mm(10:50—11:00,图略),降水强度仍维持在一个相当高的水平。与之相对应,此时强降水产生冷池西北风外泄气流逐渐增强,在11时地面最大风速增加到6~8 m/s,且地面温度梯度明

  • 图.6 2017年7月21日09—13时多普勒雷达反射率因子(阴影,单位:dBZ)与地面国家站小时极大风场(风矢,黑实线:09时回波中心;蓝实线:10时新生回波主体;黑虚线:11时雷暴主体;蓝色双箭头:12时新生回波主体;蓝色单箭头:13时新生回波主体)

  • Fig.6 Doppler radar reflectivity factor(shadow,unit:dBZ) and hourly maximum wind(wind arrow) of National Automatic Weather Station at 09:00 BST—13:00 BST on July 21,2017(black solid line:echo center at 09:00 BST;blue solid line:new echo cell at 10:00 BST;black dotted line:thunderstorm center at 11:00 BST;blue double arrow:new echo cell at 12:00 BST;blue single arrow:new echo cell at 13:00 BST)

  • 显增加(图7c)。受其影响,强回波中心向东南方向移速明显加快。12:24(图略)开始,带状回波北段逐渐减弱,其南段(图6e)受冷池西北风出流影响,向东南方向被逐渐“拉长”,呈西北东南向拉伸的片絮状回波。在冷池出流边界,温度梯度大值区,依然不断有对流回波的发生、发展,且对流发展旺盛,回波顶高达14~18 km高度,回波质心仍位于较低高度,反射率因子≥45 dBZ均分布在6 km及以下,维持典型的短时强降水回波特征,13时地面自动站小时最大雨强达72.9 mm。

  • 上述分析可知,10:42—13:00时间段,MCSs东南方向移动明显。随着中尺度对流系统的维持发展,在地面自动站风场、温度场上(图7c、d),中尺度对流系统扰动引起的动力、热力中尺度特征—雷暴出流边界、显著降温区演变过程十分明显。该阶段地面雷暴冷池形成西北风冷池出流,西北风偏冷风冷池出流与环境东南偏暖风形成辐合,造成该阶段在石家庄东南部不断有对流新生。随着冷池前缘被

  • 图.7 2017年7月21日石家庄地区09—12时地面自动站风场(风矢)、温度场(等值线,℃)演变(a、c、d为地面自动站国家站风场;b为地面加密自动站风场;红色双实线:辐合线;点划线:冷出流边界)

  • Fig.7 The evolution of wind(wind arrow) and temperature(isoline,℃) at 09:00 BST—12:00 BST on July 21,2017(a,c,d are wind fields of national Automatic Weather Station;b is the wind field of the dense Automatic Weather Station;red double solid line:convergence line;dotted line:cold outflow boundary)

  • 图.8 2017年7月21日08—14时石家庄风廓线雷达观测风场(阴影:风速≥8 m/s)

  • Fig.8 The wind observed by wind profile radar in Shijiazhuang at 08:00 BST—14:00 BST on July 21 2017(shadow:wind speed≥8 m/s)

  • 西北风向东南方向呈舌状逐渐拉伸,MCSs不断在垂直于地面自动站西北风的冷池前缘部分新生,从而使得MCSs不断“向前(东南方向)”快速传播。随着承载层西北风速的增加以及地面西北风冷池出流最大风速由4~6 m/s增加至10~12 m/s,MCSs冷池前缘向东南方向移速加快(图6e),从而影响石家庄地区的降水回波迅速东南移动,在14时雷暴移出石家庄地区,本次降水过程结束。

  • 由以上分析可知,在本阶段MCSs移动方向与风暴承载层平均风方向一致,对应的雷暴出流边界转向东南方向移动,MCSs在冷池出流边界不断的新生传播。且本阶段MCSs的移动为平流与传播同方向(东南方向)叠加,这也是本阶段系统东移速度加快的原因之一。

  • 6 结论与讨论

  • 利用多普勒雷达观测资料、地面加密自动站、雷达风廓线、多普勒雷达四维变分分析系统(VDRAS),对石家庄地区2017年7月21日一次局地强降水过程进行了分析,主要结论如下:

  • 1)本次强降水发生在“副高”588 dagpm副高线控制区,降水区具备了较好的水汽条件、热力条件和对流不稳定条件。

  • 2)降水前期,河北东北部秦皇岛、唐山地区因强降水形成较强的雷暴高压、冷池。雷暴高压产生的气压梯度力影响东北风逐渐加强,加强的东北风气流引导冷池呈舌状逐渐西南方向移动到石家庄北部地区。太行山东麓的东北风气流受太行山地形的强迫发生转向,形成东北风与西北风的辐合线。当边界层风场辐合与地面冷池前缘温度不连续面相叠加,形成低层辐合,中层辐散的不稳定垂直结构,与太行山地形迎风坡对东北气流的强迫抬升作用想配合,触发了对流不稳定能量的释放。

  • 3)在MCSs生成和发展加强过程中,向东北方向“后向传播”,其平流运动不明显,系统稳定少动,表现为“准静止状态”。本阶段MCSs的运动与雷暴冷池出流边界和东北风最大入流之间形成较强边界层中尺度辐合密切相关,新生单体不断在此中尺度辐合区生成和发展,雷暴运动在本阶段以传播为主,移速缓慢。

  • 4)“快速东移阶段”,冷池的移动方向与风暴承载层平均风即MCSs的平移方向密切相关。风暴承载层平均风为西北风,MCSs东南方向平流运动明显,对应的雷暴出流边界转向东南方向移动,随着地面冷池前缘被西北风向东南方向逐渐的拉伸,MCSs不断在垂直于地面自动站西北偏暖风的冷池前缘部分新生,从而使得MCSs前向(东南方向)传播。故本阶段MCSs移动为平流与传播同方向叠加,使得系统快速东移。

  • 本研究仅仅从观测角度详细分析了华北地区2017年7月21日发生在副热带高压内,弱天气强迫下的暖区局地暴雨触发抬升机制,研究结果表明本次过程中近地层弱冷空气的侵入、边界层的中尺度辐合系统及太行山特殊地形为雷暴触发的关键因素;雷暴被触发后,其发展、传播与自身冷池出流边界活动规律密切相关。那么,在本次过程中雷暴冷池出流边界的移动发生明显变化的原因是什么?华北暖区暴雨的中尺度对流系统发生、发展过程的三维动力、热力结构特征是什么?还需要在以后的工作中进一步深入探究。

  • 参考文献

    • [1] Bonner W D,1968.Climatology of the low level jet[J].Mon Wea Rev,96(12):833-850.

    • [2] Bryan G H,Fritsch M J,2000.Moist absolute instability:the sixth static stability state[J].Bull Amer Meteor Soc,81(6):1207-1230.

    • [3] Carbone R E,Tuttle J D,Ahijevych D,et al.,2002.Inferences of predictability associated with warm season precipitation episodes[J].J Atmos Sci,59(13):2033-2056.

    • [4] Charba J,1974.Application of gravity current model to analysis of squall-line gust front[J].Mon Wea Rev,102(2):140-156.

    • [5] 陈明轩,高峰,孙娟珍,等,2016.基于VDRAS的快速更新雷达四维变分分析系统[J].应用气象学报,27(3):257-272.Chen M X,Gao F,Sun J Z,et al.,2016.An analysis system using rapid-updating 4-D variational radar data assimilation based on VDRAS[J].J Appl Meteor Sci,27(3):257-272.(in Chinese).

    • [6] Chen S S,Frank W M,1993.A numerical study of the genesis of extratropical convective mesovortices.part Ⅰ:evolution and dynamics[J].J Atmos Sci,50(15):2401-2426.

    • [7] Chen S S,Houze R A,Mapes B E,1996.Multiscale variability of deep convection in relation to large-scale circulation in TOGA COARE[J].J Atmos Sci,53(10):1380-1409.

    • [8] Corfidi S F,2003.Cold pools and MCS propagation:forecasting the motion of downwind-developing MCSs[J].Wea Forecasting,18(6):997-1017.

    • [9] Corfidi S F,Meritt J H,Fritsch J M,1996.Predicting the movement of mesoscale convective complexes[J].Wea Forecasting,11(1):41-46.

    • [10] Craig Goff R,1976.Vertical structure of thunderstorm outflows[J].Mon Wea Rev,104(11):1429-1440.

    • [11] Davis C A,Weisman M L,1994.Balanced dynamics of mesoscale vortices produced in simulated convective systems[J].J Atmos Sci,51(14):2005-2030.

    • [12] 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 rainbands[J].Trans Atmos Sci,40(5):653-662.(in Chinese).

    • [13] Doswell C A,Brooks H E,Maddox R A,1996.Flash flood forecasting:an ingredients-based methodology[J].Wea Forecast,11(4):560-581.

    • [14] Fritsch J M,Forbes G S,2001.Mesoscale convective systems[J].Meteor Mon,28:323-357.

    • [15] Fritsch J M,Murphy J D,Kain J S,1994.Warm core vortex amplification over land[J].J Atmos Sci,51(13):1780-1807.

    • [16] 耿建军,肖现,王迎春,等,2012.变分多普勒雷达分析系统对北京一次强降水过程的短时预报能力初探[J].大气科学学报,35(6):730-736.Geng J J,Xiao X,Wang Y C,et al.,2012.A preliminary exploration on the nowcasting ability of VDRAS in a rainstorm case in Beijing[J].Trans Atmos Sci,35(6):730-736.(in Chinese).

    • [17] 何立富,陈涛,周庆亮,等,2007.北京“7.10” 暴雨β-中尺度对流系统分析[J].应用气象学报,18(5):655-665.He L F,Chen T,Zhou Q L,et al.,2007.The meso-β scale convective system of a heavy rain event on July 10,2004 in Beijing[J].J Appl Meteor Sci,18(5):655-665.(in Chinese).

    • [18] 侯淑梅,闵锦忠,王改利,等,2020.传播运动在对流风暴合并过程中的作用[J].大气科学学报,43(2):347-357.Hou S M,Min J Z,Wang G L,et al.,2020.Effect of propagation moving on the convective storm mergence process[J].Trans Atmos Sci,43(2):347-357.(in Chinese).

    • [19] Houze R A,2014.Atmospheric dynamics[M]//International Geophysics.Amsterdam:Elsevier:25-46.

    • [20] Houze R A,Rutledge S A,Biggerstaff M I,et al.,1989.Interpretation of Doppler weather radar displays of midlatitude mesoscale convective systems[J].Bull Am Meteor Soc,70(6):608-619.

    • [21] Jirak I L,Cotton W R,McAnelly R L,2003.Satellite and radar survey of mesoscale convective system development[J].Mon Wea Rev,131(10):2428-2449.

    • [22] Lane T P,Sharman R,Trier S B,et al.,2012.Recent advances in the understanding of near-cloud turbulence[J].Bull Amer Meteor Soc,93(4):499-515.

    • [23] Lemone M A,1983.Momentum transport by a line of cumulonimbus[J].J Atmos Sci,40(7):1815-1834.

    • [24] Liang Z M,Liu Y,Yin J F,et al.,2019.A case study of the effects of a synoptic situation on the motion and development of warm-sector mesoscale convective systems over South China[J].Asia-Pac J Atmos Sci,55(2):255-268.

    • [25] Meng Z Y,Zhang F Q,Markowski P,et al.,2012.A modeling study on the development of a bowing structure and associated rear inflow within a squall line over South China[J].J Atmos Sci,69(4):1182-1207.

    • [26] 苗春生,吴琼,王坚红,等,2017.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.,2017.Simulation study on effects of terrain of Dabie Mountains on rainstorm cyclone in Huaihe River Basin during Meiyu period[J].Trans Atmos Sci,40(4):485-495.(in Chinese).

    • [27] Moncrieff M W,Klinker E,1997.Organized convective systems in the tropical western Pacific as a process in general circulation models:a toga coare case-study[J].Quart J Roy Meteor Soc,123(540):805-827.

    • [28] Moore J T,Pappas C H,Glass F H,1993.Propagation characteristics of mesoscale convective systems.Preprints[C]//17th conf on severe local storms.St.Louis,MO.

    • [29] Nesbitt S W,Zipser E J,Cecil D J,2000.A census of precipitation features in the tropics using TRMM:Radar,ice scattering,and lightning observations[J].J Climate,13(23):4087-4106.

    • [30] Parker M D,Johnson R H,2000.Organizational modes of midlatitude mesoscale convective systems[J].Mon Wea Rev,128(10):3413-3436.

    • [31] Purdom J F W,1973.Picture of the month:Meso-highs and satellite imagery[J].Mon Wea Rev,101(2):180-181.

    • [32] Rotunno R,Klemp J B,Weisman M L,1988.A theory for strong,long-lived squall lines[J].J Atmos Sci,45(3):463-485.

    • [33] Schumacher C,Houze R A,2003.Stratiform rain in the tropics as seen by the TRMM precipitation radar[J].J Climate,16(11):1739-1756.

    • [34] Schumacher R S,Johnson R H,2005.Organization and environmental properties of extreme-rain-producing mesoscale convective systems[J].Mon Wea Rev,133(4):961-976.

    • [35] Skamarock W C,Weisman M L,Klemp J B,1994.Three-dimensional evolution of simulated long-lived squall lines[J].J Atmos Sci,51(17):2563-2584.

    • [36] 孙继松,何娜,郭锐,等,2013.多单体雷暴的形变与列车效应传播机制[J].大气科学,37(1):137-148.Sun J S,He N,Guo R,et al.,2013.The configuration change and train effect mechanism of multi-cell storms[J].Chin J Atmos Sci,37(1):137-148.(in Chinese).

    • [37] 王福侠,俞小鼎,裴宇杰,等,2016.河北省雷暴大风的雷达回波特征及预报关键点[J].应用气象学报,27(3):342-351.Wang F X,Yu X D,Pei Y J,et al.,2016.Radar echo characteristics of thunderstorm gales and forecast key points in Hebei Province[J].J Appl Meteor Sci,27(3):342-351.(in Chinese).

    • [38] 王丽荣,李姣,张素云,等,2019.雷达对冰雹灾害落区的跟踪及鉴定[J].灾害学,34(3):66-70.Wang L R,Li J,Zhang S Y,et al.,2019.Hail disaster area tracing and identification by radar products[J].J Catastrophology,34(3):66-70.(in Chinese).

    • [39] 王晓芳,崔春光,2011.暴雨中尺度对流系统研究的若干进展[J].暴雨灾害,30(2):97-106.Wang X F,Cui C G,2011.A number of advances of the research on heavy rain mesoscale convective systems[J].Torrential Rain Disasters,30(2):97-106.(in Chinese).

    • [40] 王秀明,俞小鼎,周小刚,2015.中国东北龙卷研究:环境特征分析[J].气象学报,73(3):425-441.Wang X M,Yu X D,Zhou X G,2015.Study of Northeast China torandoes:the environmental characteristics[J].Acta Meteorol Sin,73(3):425-441.(in Chinese).

    • [41] 王雪,林永辉,刘善峰,2019.江南一次持续性暴雨过程中线状中尺度对流系统模态转换机理研究[J].大气科学学报,42(1):138-150.Wang X,Lin Y H,Liu S F,2019.The mechanism of transition of linear mesoscale convection system mode in a continuous rainstorm process in the Jiangnan region[J].J Nanjing Inst Meteor,42(1):138-150.(in Chinese).

    • [42] 王易,徐芬,吴海英,2019.一次致雹超级单体结构特征分析[J].大气科学学报,42(4):612-620.Wang Y,Xu F,Wu H Y,2019.Structure characteristics analysis of a supercell hailstorm[J].Trans Atmos Sci,42(4):612-620.(in Chinese).

    • [43] Webster P J,Bradley E F,Fairall J S,et al.,2002.The JASMINE pilot study[J].Bull Amer Meteor Soc,83(11):1603-1630.

    • [44] Williams M,Houze R A,1987.Satellite-observed characteristics of winter monsoon cloud clusters[J].Mon Wea Rev,115(2):505-519.

    • [45] 于波,荆浩,孙继松,等,2017.北京夏季一次罕见偏南大风天气的成因分析[J].高原气象,36(6):1674-1681.Yu B,Jing H,Sun J S,et al.,2017.The analysis on an infrequent southerly gust of Beijing in summer[J].Plateau Meteor,36(6):1674-1681.(in Chinese).

    • [46] 俞小鼎,周小刚,王秀明,2012.雷暴与强对流临近天气预报技术进展[J].气象学报,70(3):311-337.Yu X D,Zhou X G,Wang X M,2012.The advances in the nowcasting techniques on thunderstorms and severe convection[J].Acta Meteorol Sin,70(3):311-337.(in Chinese).

    • [47] Yuter S E,Houze Jr R A,1998.The natural variability of precipitating clouds over the western Pacific warm pool[J].Quart J Roy Meteor Soc,124(545):53-99.

    • [48] Zhang D L,1992.The formation of a cooling-induced mesovortex in the trailing stratiform region of a midlatitude squall line[J].Mon Wea Rev,120(12):2763-2785.

    • [49] 张家国,周金莲,谌伟,等,2015.大别山西侧极端降水中尺度对流系统结构与传播特征[J].气象学报,73(2):291-304.Zhang J G,Zhou J L,Chen W,et al.,2015.The structure and propagation characteristics of the extreme-rain-producing MCS on the west side of Dabie Mountain[J].Acta Meteorol Sin,73(2):291-304.(in Chinese).

    • [50] 张艳霞,蒙伟光,戴光丰,等,2015.台风“凡亚比”登陆过程中暴雨MCSs演变及形成机理[J].热带气象学报,31(4):433-443.Zhang Y X,Meng W G,Dai G F,et al.,2015.The evolution and formation mechanism of rainstorms mcss during typhoon fnanpi landing[J].J Trop Meteor,31(4):433-443.(in Chinese).

    • [51] 赵珊珊,高歌,黄大鹏,等,2017.2004—2013年中国气象灾害损失特征分析[J].气象与环境学报,33(1):101-107.Zhao S S,Gao G,Huang D P,et al.,2017.Characteristics of meteorological disaster losses in China from 2004 to 2013[J].J Meteor Environ,33(1):101-107.(in Chinese).

    • [52] 赵宇,裴昌春,赵光平,等,2018.梅雨锋暴雨中尺度对流系统的组织特征和触发条件分析[J].大气科学学报,41(6):807-818.Zhao Y,Pei C C,Zhao G P,et al.,2018.Analysis of organization modes and initiation conditions of a heavy-rain-producing mesoscale convective system along a Meiyu front[J].Trans Atmos Sci,41(6):807-818.(in Chinese).

    • [53] Zipser E J,1977.Mesoscale and convective-scale downdrafts as distinct components of squall-line structure[J].Mon Wea Rev,105(12):15681589.

  • 参考文献

    • [1] Bonner W D,1968.Climatology of the low level jet[J].Mon Wea Rev,96(12):833-850.

    • [2] Bryan G H,Fritsch M J,2000.Moist absolute instability:the sixth static stability state[J].Bull Amer Meteor Soc,81(6):1207-1230.

    • [3] Carbone R E,Tuttle J D,Ahijevych D,et al.,2002.Inferences of predictability associated with warm season precipitation episodes[J].J Atmos Sci,59(13):2033-2056.

    • [4] Charba J,1974.Application of gravity current model to analysis of squall-line gust front[J].Mon Wea Rev,102(2):140-156.

    • [5] 陈明轩,高峰,孙娟珍,等,2016.基于VDRAS的快速更新雷达四维变分分析系统[J].应用气象学报,27(3):257-272.Chen M X,Gao F,Sun J Z,et al.,2016.An analysis system using rapid-updating 4-D variational radar data assimilation based on VDRAS[J].J Appl Meteor Sci,27(3):257-272.(in Chinese).

    • [6] Chen S S,Frank W M,1993.A numerical study of the genesis of extratropical convective mesovortices.part Ⅰ:evolution and dynamics[J].J Atmos Sci,50(15):2401-2426.

    • [7] Chen S S,Houze R A,Mapes B E,1996.Multiscale variability of deep convection in relation to large-scale circulation in TOGA COARE[J].J Atmos Sci,53(10):1380-1409.

    • [8] Corfidi S F,2003.Cold pools and MCS propagation:forecasting the motion of downwind-developing MCSs[J].Wea Forecasting,18(6):997-1017.

    • [9] Corfidi S F,Meritt J H,Fritsch J M,1996.Predicting the movement of mesoscale convective complexes[J].Wea Forecasting,11(1):41-46.

    • [10] Craig Goff R,1976.Vertical structure of thunderstorm outflows[J].Mon Wea Rev,104(11):1429-1440.

    • [11] Davis C A,Weisman M L,1994.Balanced dynamics of mesoscale vortices produced in simulated convective systems[J].J Atmos Sci,51(14):2005-2030.

    • [12] 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 rainbands[J].Trans Atmos Sci,40(5):653-662.(in Chinese).

    • [13] Doswell C A,Brooks H E,Maddox R A,1996.Flash flood forecasting:an ingredients-based methodology[J].Wea Forecast,11(4):560-581.

    • [14] Fritsch J M,Forbes G S,2001.Mesoscale convective systems[J].Meteor Mon,28:323-357.

    • [15] Fritsch J M,Murphy J D,Kain J S,1994.Warm core vortex amplification over land[J].J Atmos Sci,51(13):1780-1807.

    • [16] 耿建军,肖现,王迎春,等,2012.变分多普勒雷达分析系统对北京一次强降水过程的短时预报能力初探[J].大气科学学报,35(6):730-736.Geng J J,Xiao X,Wang Y C,et al.,2012.A preliminary exploration on the nowcasting ability of VDRAS in a rainstorm case in Beijing[J].Trans Atmos Sci,35(6):730-736.(in Chinese).

    • [17] 何立富,陈涛,周庆亮,等,2007.北京“7.10” 暴雨β-中尺度对流系统分析[J].应用气象学报,18(5):655-665.He L F,Chen T,Zhou Q L,et al.,2007.The meso-β scale convective system of a heavy rain event on July 10,2004 in Beijing[J].J Appl Meteor Sci,18(5):655-665.(in Chinese).

    • [18] 侯淑梅,闵锦忠,王改利,等,2020.传播运动在对流风暴合并过程中的作用[J].大气科学学报,43(2):347-357.Hou S M,Min J Z,Wang G L,et al.,2020.Effect of propagation moving on the convective storm mergence process[J].Trans Atmos Sci,43(2):347-357.(in Chinese).

    • [19] Houze R A,2014.Atmospheric dynamics[M]//International Geophysics.Amsterdam:Elsevier:25-46.

    • [20] Houze R A,Rutledge S A,Biggerstaff M I,et al.,1989.Interpretation of Doppler weather radar displays of midlatitude mesoscale convective systems[J].Bull Am Meteor Soc,70(6):608-619.

    • [21] Jirak I L,Cotton W R,McAnelly R L,2003.Satellite and radar survey of mesoscale convective system development[J].Mon Wea Rev,131(10):2428-2449.

    • [22] Lane T P,Sharman R,Trier S B,et al.,2012.Recent advances in the understanding of near-cloud turbulence[J].Bull Amer Meteor Soc,93(4):499-515.

    • [23] Lemone M A,1983.Momentum transport by a line of cumulonimbus[J].J Atmos Sci,40(7):1815-1834.

    • [24] Liang Z M,Liu Y,Yin J F,et al.,2019.A case study of the effects of a synoptic situation on the motion and development of warm-sector mesoscale convective systems over South China[J].Asia-Pac J Atmos Sci,55(2):255-268.

    • [25] Meng Z Y,Zhang F Q,Markowski P,et al.,2012.A modeling study on the development of a bowing structure and associated rear inflow within a squall line over South China[J].J Atmos Sci,69(4):1182-1207.

    • [26] 苗春生,吴琼,王坚红,等,2017.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.,2017.Simulation study on effects of terrain of Dabie Mountains on rainstorm cyclone in Huaihe River Basin during Meiyu period[J].Trans Atmos Sci,40(4):485-495.(in Chinese).

    • [27] Moncrieff M W,Klinker E,1997.Organized convective systems in the tropical western Pacific as a process in general circulation models:a toga coare case-study[J].Quart J Roy Meteor Soc,123(540):805-827.

    • [28] Moore J T,Pappas C H,Glass F H,1993.Propagation characteristics of mesoscale convective systems.Preprints[C]//17th conf on severe local storms.St.Louis,MO.

    • [29] Nesbitt S W,Zipser E J,Cecil D J,2000.A census of precipitation features in the tropics using TRMM:Radar,ice scattering,and lightning observations[J].J Climate,13(23):4087-4106.

    • [30] Parker M D,Johnson R H,2000.Organizational modes of midlatitude mesoscale convective systems[J].Mon Wea Rev,128(10):3413-3436.

    • [31] Purdom J F W,1973.Picture of the month:Meso-highs and satellite imagery[J].Mon Wea Rev,101(2):180-181.

    • [32] Rotunno R,Klemp J B,Weisman M L,1988.A theory for strong,long-lived squall lines[J].J Atmos Sci,45(3):463-485.

    • [33] Schumacher C,Houze R A,2003.Stratiform rain in the tropics as seen by the TRMM precipitation radar[J].J Climate,16(11):1739-1756.

    • [34] Schumacher R S,Johnson R H,2005.Organization and environmental properties of extreme-rain-producing mesoscale convective systems[J].Mon Wea Rev,133(4):961-976.

    • [35] Skamarock W C,Weisman M L,Klemp J B,1994.Three-dimensional evolution of simulated long-lived squall lines[J].J Atmos Sci,51(17):2563-2584.

    • [36] 孙继松,何娜,郭锐,等,2013.多单体雷暴的形变与列车效应传播机制[J].大气科学,37(1):137-148.Sun J S,He N,Guo R,et al.,2013.The configuration change and train effect mechanism of multi-cell storms[J].Chin J Atmos Sci,37(1):137-148.(in Chinese).

    • [37] 王福侠,俞小鼎,裴宇杰,等,2016.河北省雷暴大风的雷达回波特征及预报关键点[J].应用气象学报,27(3):342-351.Wang F X,Yu X D,Pei Y J,et al.,2016.Radar echo characteristics of thunderstorm gales and forecast key points in Hebei Province[J].J Appl Meteor Sci,27(3):342-351.(in Chinese).

    • [38] 王丽荣,李姣,张素云,等,2019.雷达对冰雹灾害落区的跟踪及鉴定[J].灾害学,34(3):66-70.Wang L R,Li J,Zhang S Y,et al.,2019.Hail disaster area tracing and identification by radar products[J].J Catastrophology,34(3):66-70.(in Chinese).

    • [39] 王晓芳,崔春光,2011.暴雨中尺度对流系统研究的若干进展[J].暴雨灾害,30(2):97-106.Wang X F,Cui C G,2011.A number of advances of the research on heavy rain mesoscale convective systems[J].Torrential Rain Disasters,30(2):97-106.(in Chinese).

    • [40] 王秀明,俞小鼎,周小刚,2015.中国东北龙卷研究:环境特征分析[J].气象学报,73(3):425-441.Wang X M,Yu X D,Zhou X G,2015.Study of Northeast China torandoes:the environmental characteristics[J].Acta Meteorol Sin,73(3):425-441.(in Chinese).

    • [41] 王雪,林永辉,刘善峰,2019.江南一次持续性暴雨过程中线状中尺度对流系统模态转换机理研究[J].大气科学学报,42(1):138-150.Wang X,Lin Y H,Liu S F,2019.The mechanism of transition of linear mesoscale convection system mode in a continuous rainstorm process in the Jiangnan region[J].J Nanjing Inst Meteor,42(1):138-150.(in Chinese).

    • [42] 王易,徐芬,吴海英,2019.一次致雹超级单体结构特征分析[J].大气科学学报,42(4):612-620.Wang Y,Xu F,Wu H Y,2019.Structure characteristics analysis of a supercell hailstorm[J].Trans Atmos Sci,42(4):612-620.(in Chinese).

    • [43] Webster P J,Bradley E F,Fairall J S,et al.,2002.The JASMINE pilot study[J].Bull Amer Meteor Soc,83(11):1603-1630.

    • [44] Williams M,Houze R A,1987.Satellite-observed characteristics of winter monsoon cloud clusters[J].Mon Wea Rev,115(2):505-519.

    • [45] 于波,荆浩,孙继松,等,2017.北京夏季一次罕见偏南大风天气的成因分析[J].高原气象,36(6):1674-1681.Yu B,Jing H,Sun J S,et al.,2017.The analysis on an infrequent southerly gust of Beijing in summer[J].Plateau Meteor,36(6):1674-1681.(in Chinese).

    • [46] 俞小鼎,周小刚,王秀明,2012.雷暴与强对流临近天气预报技术进展[J].气象学报,70(3):311-337.Yu X D,Zhou X G,Wang X M,2012.The advances in the nowcasting techniques on thunderstorms and severe convection[J].Acta Meteorol Sin,70(3):311-337.(in Chinese).

    • [47] Yuter S E,Houze Jr R A,1998.The natural variability of precipitating clouds over the western Pacific warm pool[J].Quart J Roy Meteor Soc,124(545):53-99.

    • [48] Zhang D L,1992.The formation of a cooling-induced mesovortex in the trailing stratiform region of a midlatitude squall line[J].Mon Wea Rev,120(12):2763-2785.

    • [49] 张家国,周金莲,谌伟,等,2015.大别山西侧极端降水中尺度对流系统结构与传播特征[J].气象学报,73(2):291-304.Zhang J G,Zhou J L,Chen W,et al.,2015.The structure and propagation characteristics of the extreme-rain-producing MCS on the west side of Dabie Mountain[J].Acta Meteorol Sin,73(2):291-304.(in Chinese).

    • [50] 张艳霞,蒙伟光,戴光丰,等,2015.台风“凡亚比”登陆过程中暴雨MCSs演变及形成机理[J].热带气象学报,31(4):433-443.Zhang Y X,Meng W G,Dai G F,et al.,2015.The evolution and formation mechanism of rainstorms mcss during typhoon fnanpi landing[J].J Trop Meteor,31(4):433-443.(in Chinese).

    • [51] 赵珊珊,高歌,黄大鹏,等,2017.2004—2013年中国气象灾害损失特征分析[J].气象与环境学报,33(1):101-107.Zhao S S,Gao G,Huang D P,et al.,2017.Characteristics of meteorological disaster losses in China from 2004 to 2013[J].J Meteor Environ,33(1):101-107.(in Chinese).

    • [52] 赵宇,裴昌春,赵光平,等,2018.梅雨锋暴雨中尺度对流系统的组织特征和触发条件分析[J].大气科学学报,41(6):807-818.Zhao Y,Pei C C,Zhao G P,et al.,2018.Analysis of organization modes and initiation conditions of a heavy-rain-producing mesoscale convective system along a Meiyu front[J].Trans Atmos Sci,41(6):807-818.(in Chinese).

    • [53] Zipser E J,1977.Mesoscale and convective-scale downdrafts as distinct components of squall-line structure[J].Mon Wea Rev,105(12):15681589.

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