| 2015年5月华南一次龙卷过程观测分析 |
| |
| 引用本文： | 陈元昭,俞小鼎,陈训来,王书欣,罗鸣.2015年5月华南一次龙卷过程观测分析[J].应用气象学报,2016,27(3):334-341. |
| |
| 作者姓名： | 陈元昭 俞小鼎 陈训来 王书欣 罗鸣 |
| |
| 作者单位： | 1.广东省深圳市气象局，深圳 518040 |
| |
| 基金项目： | 资助项目： 国家自然科学基金项目（41175043，41461164006），公益性行业气象（科研）专项（GYHY201506006），华南区域气象中心气象科技攻关项目(GRMC2014M08)，广东省科技计划项目（20140218），广东省气象局临近预报创新团队（201503） |
| |
| 摘 要： | 利用常规观测、珠江三角洲区域自动气象站、广州多普勒天气雷达、深圳机场风廓线雷达及NCEP/NCAR等资料对2015年5月11日下午发生在深圳宝安机场附近的一次龙卷天气过程进行分析。结果表明:这次龙卷发生在500 hPa槽前、850 hPa切变线南侧以及地面冷锋的暖区一侧，上干冷、下暖湿的结构加剧了条件不稳定，环境对流有效位能很大，风垂直切变强，水汽丰富；产生龙卷的回波快速演变为逗点回波，出现钩状回波，龙卷发生在钩状回波内侧的弱回波区附近；与之对应的中气旋旋转速度不断加大，半径减小，并向低层发展。
|
| 关 键 词： | 龙卷 微型超级单体 中气旋 |
| 收稿时间： | 2015-11-05 |
A Tornado in South China in May 2015 |
| |
| Chen Yuanzhao,Yu Xiaoding,Chen Xunlai,Wang Shuxin and Luo Ming.A Tornado in South China in May 2015[J].Quarterly Journal of Applied Meteorology,2016,27(3):334-341. |
| |
| Authors: | Chen Yuanzhao Yu Xiaoding Chen Xunlai Wang Shuxin and Luo Ming |
| |
| Affiliation: | 1.Shenzhen Meteorological Bureau of Guangdong, Shenzhen 5180402.Shenzhen Key Laboratory of Severe Weather in South China, Shenzhen 5180403.CMA Training Center, Beijing 100081 |
| |
| Abstract: | A severe tornado event near Baoan International Airport of Shenzhen, Guangdong Province on 11 May 2015 is investigated. Based on the routine upper-air, surface automatic weather station (AWS), Doppler radar, wind profile data and NCEP 6-hour analysis data (1°×1°), the environmental condition, structure and evolution are analyzed. The intensity of this tornado belongs to the F1 tornado intensity category. The tornado event occurs in front of 500 hPa trough, warm and moist area ahead of 850 hPa shear lines and the warm section before surface cold front. It is significant that the atmospheric convective instability is strengthened by the low temperature and humidity increasing, and the dry cold air behind 500 hPa trough moving eastward. The calculation of atmospheric convective parameters shows that there is powerful convective available potential energy (CAPE), strong low-level vertical wind shear and abundant water vapor in atmospheric environment before the tornado occurs. The analysis of Doppler radar products also indicates that the storm has a life span lasting about 1 hour, during which its echo top extends the height of nearly 5 km. The tornado initially comes from a quasi-linear convective system along the surface convergence line. The quasi-linear convective system moves slowly down and becomes a massive comma echo, finally develops into hooked echo, and the tornado is detected near the weak echo area. The echo of the strongest center value reaches 62 dBZ. The tornado locates at the edge of the strongest echo gradient region near the weak echo region, which indicates that the strong updraft contributes most to the tornado. The mesocyclone first appears in the middle cell of the storm, beginning at 3 km height and then developing upward and downward. The height of the strong core (no less than 50 dBZ) is below 5 km in the tornado event, making it a low centroid convective system. The mesocyclone always shows cyclonic rotation characteristics from originated to maturity in the radial velocity chart. When the rotational speed increases, the radius of the mesocyclone decreases and the largest vertical vorticity associate with the mesocyclone is 1.2×10-2 s-1. The distance separating the strongest inbound and outbound radial velocities (called velocity couplet) is reduced from 8 km to 6 km. The mesocyclone deepens gradually downwards, producing the tornado. When the tornado is underway, strong divergence occurs at the storm top above the tornado. Therefore, in operational work more attention should be paid to the sudden change of echo shape and rapidly developing cyclone vortex. |
| |
| Keywords: | tornado super cell mesocyclone |
|
| 点击此处可从《应用气象学报》浏览原始摘要信息 |
|
点击此处可从《应用气象学报》下载全文 |
|
