主办单位:中国气象局沈阳大气环境研究所
国际刊号:ISSN 1673-503X
国内刊号:CN 21-1531/P

气象与环境学报 ›› 2021, Vol. 37 ›› Issue (2): 1-11.doi: 10.3969/j.issn.1673-503X.2021.02.001

• 论文 • 上一篇    下一篇

双台风“纳沙”和“海棠”登陆后强度变化成因及对比分析

林小红1,2(),蔡义勇3,*(),韩美2,郭弘2,刘通易2   

  1. 1. 福建省灾害天气重点实验室, 福建 福州 350001
    2. 福建省气象台, 福建 福州 350001
    3. 福建省气象科学研究所, 福建 福州 350001
  • 收稿日期:2020-03-11 出版日期:2021-04-01 发布日期:2021-04-02
  • 通讯作者: 蔡义勇 E-mail:pop_lxh@163.com;caiyy@pku.org.cn
  • 作者简介:林小红,女,1975年生,高级工程师,主要从事台风与暴雨研究,E-mail:pop_lxh@163.com
  • 基金资助:
    福建省气象局2019年度开放式基金项目(海峡所)(2019KH01);福建省灾害天气重点实验室重大科技专项(2020TF01);福建省灾害天气重点实验室重大科技专项(2020TF04);中国气象局预报员专项(CMAYBY2018-035)

Comparative analysis of strength variation of double typhoons of "Nesat" and "Haitang" after landing in Fujian province

Xiao-hong LIN1,2(),Yi-yong CAI3,*(),Mei HAN2,Hong GUO2,Tong-yi LIU2   

  1. 1. Fujian Provincial Key Laboratory of Disaster Weather, Fuzhou 350001, China
    2. Fujian Provincial Meteorological Observatory, Fuzhou 350001, China
    3. Fujian Provincial Institute of Meteorological Science, Fuzhou 350001, China
  • Received:2020-03-11 Online:2021-04-01 Published:2021-04-02
  • Contact: Yi-yong CAI E-mail:pop_lxh@163.com;caiyy@pku.org.cn

摘要:

利用NCEP(National Centers for Environmental Prediction)再分析资料对2017年双台风“纳沙”(1709)和“海棠”(1710)先后登陆福建后的强度变化特征进行对比分析。结果表明:低纬水汽输送的强弱变化是造成双台风强度变化的主要原因,而越赤道气流对水汽输送起到关键作用。副热带西风急流与中低空风场强弱变化一致,西风急流增强伴随中低空东风加强是“海棠”陆上强度维持不减的原因之一,反之“纳沙”快速减弱。双台风效应对强度变化也起着重要作用:双台风靠近相吸作用下,“纳沙”残余环流卷入“海棠”环流中,为其输送正涡度因子及斜压能量,也是促使“海棠”强度维持的原因。台风登陆后,其上空三种不同层差的垂直风切变值表现一致减小的变化趋势及低于6 m·s-1的风切,有利于弱台“海棠”陆上长久维持。海岸锋生及海表通量动热力因子对“海棠”右侧中小尺度对流发展和维持起到重要作用,加剧了“海棠”非对称性结构,促使“海棠”强度维持不减。

关键词: 双台风, 台风强度, 水汽输送

Abstract:

Base on the reanalysis data of the National Centers for Environmental Prediction (NCEP), the strength variations of the double typhoons of "Nesat" (1709) and "Haitang" (1710) after successively landing in Fujian province in 2017 were diagnosed and comparatively analyzed.The results show that the strength variation of water vapor transport at low latitudes is the main reason for the strength difference of the double typhoons.The equatorial crossing airflow plays a key role in water vapor transport.The intensity of subtropical westerly jet is consistent with that of the mid-low level wind field, and the rapid enhancement of subtropical westerly jet is accompanied by an enhancement in the mid-low level easterly wind, which are the reason for the strength of "Haitang" typhoon remains unchanged, whereas that of "Nesat" typhoon decreases rapidly.The effect of double typhoons plays an important role in the strength variation.When the double typhoons close to and interact with each other, the residual circulation of the "Nesat" typhoon is involved in the circulation of the "Haitang" typhoon, which transports a positive vorticity factor and baroclinic energy to "Haitang" typhoon.After the typhoon' landing, the value of vertical wind shear of three different layers shows a consistent decreasing trend.When it is below 6 m·s-1, it is favorable for the long-term maintenance on land for the weak typhoon "Haitang".The coastal Frontogenesis and thermodynamic factors of sea surface flux play an important role in developing and maintaining the meso- and small-scale convection along Fujian and Guangdong provincial coasts, which aggravates the asymmetric structure of "Haitang" typhoon, and consequently promotes the strength of "Haitang" typhoon to remain unchanged.

Key words: Double typhoons, Typhoon intensity, Water vapor transport

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