气候与水文

甘肃一次副高内部极端强降水可预报性思考

展开
  • 1兰州中心气象台,甘肃兰州7300202甘肃省公共气象服务中心,甘肃兰州730020
狄潇泓(1975-),女,高工,本科,研究方向为天气预报. E-mail:xhdi@sohu.com

收稿日期: 2019-03-12

  修回日期: 2019-07-27

  网络出版日期: 2019-09-19

基金资助

公益性行业专项(GYHY201506006)

Predictability of an extreme heavy rainfall inside the subtropical high pressure in Gansu

Expand
  • 1 Lanzhou Centre Meteorological Observation,Lanzhou 730020,Gansu,China; 2 Gansu Provincial Meteorological Service Center,Lanzhou 730020,Gansu,China

Received date: 2019-03-12

  Revised date: 2019-07-27

  Online published: 2019-09-19

摘要

传统认为副高内部下沉运动,抑制对流运动的发生,但是甘肃河东隔几年就会出现一次副高内部的强降水过程,而全球业务模式对此类强降水预报能力较弱,导致副高内部的强降水天气预报难度很大。利用多种常规和非常规观测资料,对2016年8月22日甘肃副高内部的一次极端强降水过程进行分析,以期发现一些可用预报指标,结果表明:青藏高压东北部辐散区和近地面层的中尺度辐合线的叠置,有利于形成强烈的上升运动,是强降水发生的天气背景条件。环境场极高的水汽含量,异常厚的暖云层,和小的垂直风切变有利于形成极大的降水效率,是强降水的增强条件。通过对各种中尺度观测资料的分析,发现一些对强降水预报预警有指示作用的因子:(1) 对流云团冷云盖中心区域运动前方逐时云顶亮温(TBB)梯度最大处对应地面降水最强降水。(2) 闪电总次数峰值后1~2 h,且闪电带变的很有组织时,对应地面最强降水时段。(3) 造成强降水的对流单体的雷达回波表现出低质心暖云降水的特征。(4) 在组合反射率(CR)、垂直液态水含量(VIL)最大值出现后30~40 min,最强雨强出现。

本文引用格式

狄潇泓, 王小勇, 肖玮 . 甘肃一次副高内部极端强降水可预报性思考[J]. 干旱区地理, 2019 , 42(5) : 1029 -1037 . DOI: 10.12118/j.issn.1000-6060.2019.05.08

Abstract

Traditionally,the subtropical highs are considered to be dominated by downward motion,not conducive to precipitation in these areas.But there have been a heavy precipitation within the subtropical high every few years in Gansu Province,China.It is very difficult to forecast heavy rainfall inside the subtropical high.An extreme heavy precipitation process under the control of the subtropical high occurred in Gansu are analyzed by a variety of conventional and unconventional observations to study its forming mechanism.From the prediction results of models,it is found that the large scale model behaved poorly in predicting this kind of heavy rainfall.Through the observation data,the overlay of the area of divergence in northeastern Qinghai-Tibetan Plateau with high pressure and the mesoscale convergence line near surface layer contributed to form a strong upward movement,which constituted the weather condition of the heavy precipitation.Against this background,abundant water vapor,extremely thick warm clouds,and weak vertical wind shear created a high probability of strong precipitation.By analyzing various meso-scale observation data,some factors that have indicative effect in predicting such heavy rainfall have been found as follows: (1) The maximum gradient of TBB (Temperature of Black-Body) in front of the movement direction of the cold desk center in the convective cloud cluster was the place with the strongest precipitation. (2) The strongest precipitation occurred about 1-2 hours after the total number of lightning reached its peak and with the lightning places were well positioned. (3) Radar echoes of the convective bodies which caused heavy rainfall have echo characteristics of warm cloud precipitation with low mass center. (4) The strongest rain intensity appeared about 30-40 minutes after the maximums of CR and VIL were reached.

参考文献

[1]陶诗言.中国之暴雨[M].北京:科学出版社,1980:35.[TAO Shiyan.Torrential rain in China[M].Beijing:Science Press,1980:35.] [2]陶健红,王宝鉴.甘肃省短期天气预报员手册[M].北京:气象出版社,2012:86.[TAO Jianhong, WANG Baojian.Handbook for short-term weather forecasters in Gansu[M].Meteorology Press,2012:86.] [3]白肇烨,徐国昌.中国西北天气[M].北京:气象出版社,1988:215-216.[BAI Zhaoye,XU Guochang.The weather in the Northwest of China[M].Beijing:Meteorology Press,1988:215-216.] [4]吴国雄,丑纪范,刘屹岷,等.副热带高压研究进展及展望[J].大气科学,2003,27(4):503-517.[WU Guoxiong,CHOU Jifan,Liu Yimin,et al.Review and prospect of the study on the subtropical anticyclone[J].Chinese Journal of Atmospheric Sciences,2003,27(4):503-517.] [5]傅云飞,冼桃.副热带高压中心区域内云和降水气候特征研究回顾与展望[J].暴雨灾害,2017,36(6):489-497.[FU Yunfei, XIAN Tao.Review and prospect of climate characteristics of cloud and precipitation in subtropical high center[J].Torrential Rain and Disasters,2017,36(6):489-497] [6]曹美兰,俞燎霓.一次发生在副高内的强对流天气的诊断分析[J].科技通报,2012,28(1):58-61.[CAO Meilan,YU Liaoni.The diagnosis of severe convective weather occurred in the subtropical high[J].Bulletin of Science and Technoidgy,2012,28(1):58-61.] [7]尹红萍,曹晓岗.盛夏上海地区副热带高压型强对流特点分析[J].气象,2010,36(8):19-25.[YIN Hongping,CAO Xiaogang.Summary on subtropical high severe convection during midsummer in Shanghai area[J].Meteorological Monthly,2010,36(8):19-25.] [8]支树林,陈娟,包慧漾.一次副热带高压边缘上大暴雨的中尺度特征分析[J].气象,2015,41(10):1203-1214.[ZHI Shulin,CHEN Juan,BAO Huiyang.Mesoscale characteristics analysis of rainstorm on the edge of subtropical high[J].Meteorological Monthly,2015,41(10):1204-1215.] [9]赵庆云,狄潇泓,张铁军.“8·19”甘肃区域暴雨的特征分析及数值模拟[J].干旱气象,2005,23(4):12-16.[ZHAO Qingyun,DI Xiaohong,ZHANG Tiejun.Analysis and numerical simulation of the heavy rain in Gansu Province on 19 August 2004[J].Arid Meteorology,2005,23(4):12-16.] [10]李如琦,李建刚,王江,等.南疆西部暴雨过程的动力热力结构分析[J].干旱区地理,2018,41(1):9-16.[LI Ruqi,LI Jiangang,WANG Jiang,et al.Dynamic and thermal structure characteristics of the rainstorms in the west of South Xinjiang[J].Arid Land Geography,2018,41(1):9-16.] [11]许东蓓,刘抗,孟丽霞,等.“8.12”甘肃大暴雨特征分析[J].干旱区地理,2013,36(2):245-252[XU Dongbei,LIU Kang,MENG Lixia,et al.Charactertics of heavy rainfall occurred on 12 August 2010 in Gansu,China[J].Arid Land Geography,2013,36(2):245-252] [12]程瑛,黄武斌,沙宏娥.甘肃岷县两次强降水致山洪泥石流灾害特征对比分析[J].干旱区地理,2018,41(3):443-448.[CHENG Ying,HUANG Wubin,SHA Honger.Cause of two heavy rainfall causing massive mudslide in Minxian County,Gansu Province[J].Arid Land Geography,2018,41(3):443-448] [13]付双喜,何金梅.甘肃短时强降水天气若干环境参数特征分析[J].干旱区地理,2015,38(3):469-477.[FU Shuangxi,HE Jinmei.Shorttime heavy precipitation characteristics of several environmental parameters of Gansu Province[J].Arid Land Geography,2015,38(3):469-477.] [14]DOSWELL III C A, BROOKS H E, MADDOX R A.Flash flood forecasring:An ingredients based methodology[J].Wea Forecasting,1996,11:560-581. [15]孙军,谌芸,杨舒楠,等.北京721特大暴雨极端性分析及思考(二)极端性降水成因初探及思考[J].气象,2012,38(10):1267-1277.[SUN Jun,CHEN Yun,YANG Shunan,et al.Analysis and thinking on the extremes of the 21 July 2012 torrential rain in Beijing partⅡ:Preliminary causation analysis and thinking[J].Meteorological Monthly,2012,38(10):1267-1277.] [16]方翀,毛冬艳,张小雯,等.2012年7月21日北京地区特大暴雨中尺度对流条件和特征初步分析[J].气象,2012,38(10):1278-1287.[FANG Chong,MAO Dongyan,ZHANG Xiaowen,et al.Analysis on the mesoscale convective comditions and characteristics of an extreme torrential rain in Beijing on 21 July 2012[J].Meteorological Monthly,2012,38(10):1278-1287.] [17]章国材,矫梅燕,李延香,等.现代天气预报技术和方法[M].北京:气象出版社,2007:103.[ZHANG Guocai,JIAO Meiyan,LI Yanxiang,et al.Modern weather forecast techniques and methods[M].Beijing:Meteorology Press,2017:103.] [18]付双喜,安林,康凤琴,等.VIL在识别冰雹云中的应用及估测误差分析[J].高原气象,2004,23(6):811-815.[FU Shuangxi,AN Lin,KANG Fengqin,et al.Application of VIL in identification of hailstorms and estimation error analysis[J].Plateau Meteorology,2004,23(6):811-815.]
文章导航

/