论文

弱天气尺度背景下湖南两次暖区暴雨对比分析

  • 唐佳 ,
  • 叶成志 ,
  • 唐明晖 ,
  • 许霖 ,
  • 何炜炜 ,
  • 付炜
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  • <sup>1.</sup>湖南省气象台,湖南 长沙 410118;<sup>2.</sup>气象防灾减灾湖南省重点实验室,湖南 长沙 410118;<sup>3.</sup>国家电投集团能源科技工程有限公司,上海 201100;<sup>4.</sup>永州市气象局,湖南 永州 425000

收稿日期: 2019-11-14

  网络出版日期: 2021-08-28

基金资助

中国气象局气象预报业务关键技术发展专项(YBGJXM(2018)1A-10);中国气象局预报员专项(CMAYBY2019-077);湖南暖区暴雨预报预警技术研究及业务应用项目(NLJS 03)

Contrast Analysis of Two Warm-Sector Heavy Rainfall Processes under Weak Synoptic Scale Background in Hunan

  • Jia TANG ,
  • Chengzhi YE ,
  • Minghui TANG ,
  • Lin XU ,
  • Weiwei HE ,
  • Wei FU
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  • <sup>1.</sup>Hunan Meteorological Bureau,Changsha 410118,Hunan,China;<sup>2.</sup>Key Laboratory of Meteorological Disaster Prevention and Mitigation in Hunan Province,Changsha 410118,Hunan,China;<sup>3.</sup>State power investment corporation energy technology & engineering company,Shanghai 201100,China;<sup>4.</sup>Hunan Yongzhou Meteorological Bureau,Yongzhou 425000,Hunan,China

Received date: 2019-11-14

  Online published: 2021-08-28

摘要

首先对2008 -2019年4 -9月湖南弱天气尺度背景下暖区暴雨依据500 hPa环流形势分为强西南急流型和副高型, 然后对2018年4月30日(简称“4·30”过程)和2016年7月17日(简称“7·17”过程)两次不同类型暖区暴雨过程进行对比分析。结果表明: (1)两类暖区暴雨具有明显季节差异, 强西南急流型和副高型分别发生在春季和夏季。强西南急流型一天任何时刻均会出现, 夜间降水频次增多。副高型的日变化明显, 降水峰值出现在上午。强西南急流型降水范围广, 多出现在湘南地区, 西南急流北推到长江中下游地区时, 湘北也会出现暴雨。副高型降水分散, 在湘西北、 湘北及湘东南地区均出现强降水, 局地性强, 对流性明显。(2)“4·30”过程暴雨区处于上下一致西南风中, 在切变线南侧辐合上升、 西南急流和地面辐合线共同影响下湘东北出现暴雨, 属于强西南急流型暖区暴雨; 而“7·17”过程, 副高脊线控制湖南, 受中低层弱切变和地面中尺度气旋影响, 湘西北出现暴雨, 属于副高型暖区暴雨。(3)“4·30”过程暴雨区上空垂直螺旋度均为负值, 700 hPa存在负值中心, 意味着700 hPa切变线造成暴雨区强辐合上升, 导致强降水发生; “7·17”过程, 垂直螺旋度呈“上正下负”结构, 900 hPa高度强气旋性旋转辐合最强, 表征近地层中小尺度系统影响造成暴雨。“4·30”过程水汽输送和辐合比“7·17”过程更强。“7·17”过程比“4·30”过程低层热力不稳定能量更大且热力不稳定层结更强。β中尺度辐合线和γ小尺度气旋分别为 “4·30”过程和“7·17”过程的触发机制。

本文引用格式

唐佳 , 叶成志 , 唐明晖 , 许霖 , 何炜炜 , 付炜 . 弱天气尺度背景下湖南两次暖区暴雨对比分析[J]. 高原气象, 2021 , 40(4) : 815 -828 . DOI: 10.7522/j.issn.1000-0534.2020.00062

Abstract

Warm-sector heavy rainfalls under weak synoptic scale background in Hunan during April-September in 2008 -2019 are divided into strong southwest jet type and subtropical high type according to 500 hPa circulation situation, and then two different types of warm-sector heavy rainfall cases under weak synoptic scale background on April 30, 2018 ("4·30" case) and July 17, 2016 ("7·17" case) are analyzed.Results are as follows: (1)There are obvious seasonal differences between the two types of Warm-sector heavy rainfalls.Strong southwest jet and subtropical high occur in spring and summer, respectively.The strong southwestern jet type appears at any time of the day, and the frequency of precipitation at night increases.Diurnal variation of the subtropical high type is obvious, and the peak appears in the morning.The precipitation of strong southwestern jet type is distributed widely, and mostly occurs in the southern Hunan.When the southwestern jet moves northward to the middle-lower reaches of Yangtze River, heavy rainfalls also occur in northern Hunan.Precipitation of Subtropical type distributes dispersedly, and occurs in northwestern, northern, and southeastern of Hunan, with strong locality and obvious convection.(2)Rainstorm area of the "4·30" case is in lower-to-upper southwest wind, and occurs in Northeast Hunan under influences of convergence and updraft on south side of shear line, southwest jet and surface convergence line, belonging to the strong southwest jet type of warm -sector heavy rainfall.The "7·17" case is affected by weak shear in the middle and lower levels and surface mesoscale cyclone, under the control of subtropical high.Heavy rain occurs in the northwest of Hunan, belonging to subtropical high type of warm sector heavy rainfall.(3)The values of vertical helicity over the rainstorm area during "4·30" case are all negative, and there is a negative center in 700 hPa, which means that the shear line in 700 hPa causes strong upward convergence in rainstorm area, leading to this heavy precipitation.During "7·17" case, vertical helicity shows a structure of positive in upper level and negative in lower level, strong cyclonic rotatory convergence is the strongest in 900 hPa level, indicating that the heavy rainfall is caused by the mesoscale and small scale systems in the near surface level.Water vapor transport and convergence in "4·30" case are stronger than that in "7·17" case.Thermal instability energy in the lower level of the "7·17" case is larger, and thermal instability stratification is stronger than that in the "4·30" case.β-mesoscale convergence lines and γ-cyclones are the triggering mechanisms of "4·30 "and "7·17" cases, respectively.

参考文献

[1]Chen H, Yu R, Li J, al et, 2010.Why nocturnal long-duration rainfall presents an eastward-delayed diurnal phase of rainfall down the Yangtze River Valley[J].Journal Climate, 23: 905-917.
[2]陈娟, 许彬, 郑婧, 等, 2015.非常规探测资料在江西一次暖区暴雨过程分析中的应用[J].气象与减灾研究, 38(4): 20-29.
[3]陈翔翔, 丁治英, 刘彩虹, 等, 2012.2000 -2009年5、 6月华南暖区暴雨形成系统统计分析[J].热带气象学报, 28(5): 707-718.
[4]陈玥, 谌芸, 陈涛, 等, 2016.长江中下游地区暖区暴雨特征分析[J].气象, 42(6): 724-731.
[5]陈云辉, 金米娜, 许爱华, 2015.江西省一次短历时暖区暴雨中尺度结构及发生维持机制分析[J].气象与减灾研究, 38(3): 26-34.
[6]戴泽军, 蔡荣辉, 彭莉莉, 等, 2019.湖南持续性区域暴雨气候特征及暴雨落区分型[J].高原气象, 38(3): 573-582.DOI: 10. 7522/j.issn.1000-0534.2018.00094.
[7]何立富, 陈涛, 孔期, 2016.华南暖区暴雨研究进展[J].应用气象学报, 27(5): 559-569.
[8]梁海河, 阮征, 葛润生, 2004.华南暴雨试验天气雷达数据处理及暴雨中尺度结构个例分析[J].应用气象学报, 15(3): 281-290.
[9]刘蕾, 李宜爽, 张凌云, 等, 2016.广西汛期2次暖区暴雨成因的对比分析[J].中国农学通报, 32(5): 136-143.
[10]罗建英, 廖胜石, 黄归兰, 等, 2009.广西前汛期锋前暖区暴雨过程的模拟与分析[J].气象, 32(10): 50-57.
[11]慕建利, 王建捷, 李泽椿, 2008.2005年6月华南特大连续性暴雨的环境条件和中尺度扰动分析[J].气象学报, 66(3): 437-451.
[12]冉令坤, 楚艳丽, 2009.强降水过程中垂直螺旋度和散度通量及其拓展形式的诊断分析[J].物理学报, 58(11): 8094-8106.
[13]孙健, 赵平, 周秀骥, 2002.一次华南暴雨的中尺度结构及复杂地形的影响[J].气象学报, 60(3): 333-342.
[14]唐明晖, 李巧媛, 丁小剑, 等, 2012.“6.19”湖南大范围暴雨中“列车效应”的多普勒雷达特征[J].暴雨灾害, 31(4): 313-320.
[15]汪玲瑶, 谌芸, 肖天贵, 等, 2018.夏季江南地区暖区暴雨的统计分析[J].气象, 44(6): 771-780.
[16]王华, 李宏宇, 仲跻芹, 等, 2019.京津冀一次罕见的双雨带暴雨过程成因分析[J].高原气象, 38(4): 856-871.DOI: 10.7522/j.issn.1000-0534.2018.00102.
[17]王珏, 沈新勇, 寿绍文, 等, 2008.06·6福建大暴雨的数值模拟及复杂地形影响试验[J].南京气象学院学报, 31(4): 546-554.
[18]伍志方, 蔡景就, 林良勋, 等, 2018.2017年广州“5·7”暖区特大暴雨的中尺度系统和可预报性[J].气象, 44(4): 485-499.
[19]徐燚, 闫敬华, 王谦谦, 等, 2013.华南暖区暴雨的一种低层重力波触发机制[J].高原气象, 32(4): 1050-1061.DOI: 10.7522/j.issn.1000-0534.2012.00100.
[20]叶朗明, 苗峻峰, 2014.华南一次典型回流暖区暴雨过程的中尺度分析[J].暴雨灾害, 33(1): 342-350.
[21]岳彩军, 郭煜, 寿绍文, 等, 2011.螺旋度在我国多种灾害性天气研究中的应用进展[J].暴雨灾害, 30(2): 107-116.
[22]张晓美, 蒙伟光, 张艳霞, 等, 2009.华南暖区暴雨中尺度对流系统的分析[J].热带气象学报, 25(5): 551-560.
[23]周广强, 赵春生, 丁守国, 等, 2005.不同辐射传输方案对中尺度降水影响的对比分析[J].应用气象学报, 16(2): 148-158.
[24]周明飞, 杜小玲, 熊伟, 2014.贵州初夏两次暖区暴雨的对比分析[J].气象, 40(2): 186-195.
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