| 摘要: |
| 该文利用务川C波段双偏振雷达和常规资料分析了2021年3月30日贵州西北部一次冰雹天气的成因和偏振参量特征。研究表明，当日贵州处于低层气旋性切变和高层强正涡度平流区域内，贵州东北部有中等到强的垂直风切变，且发现干舌与地面辐合线相交处有利于激发强烈的上升气流。强回波成熟阶段，最大水平反射率因子达到70 dBz，并出现钩状回波、三体散射长钉、有界弱回波区和回波悬垂现象。偏振参量分析表明，此次过程出现冰雹时，ZH值在60 dBz以上，ZDR值较低在-2~1.75 dB，对于湿冰雹ZDR值偏高在3~6 dB，KDP值在0 dB左右，伴有强降水时KDP值较大在2~6 °/km，CC值较低在0.85~0.93。在湿球0 ℃高度以上出现了伴随强上升气流的ZDR柱和KDP柱。三体散射长钉在ZDR和CC图中有很好的体现，且CC图中还出现非均匀波束充塞现象。 |
| 关键词: C波段双偏振雷达；冰雹；干舌 |
| DOI： |
| 投稿时间：2021-06-21 |
| 基金项目:贵州省气象局科研业务项目（黔气科登[2021]06-02号）：双偏振雷达产品在2021年贵州东部冰雹天气中的应用分析 |
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| Analysis of Dual Polarization Characteristics of a Hailstorm in North Guizhou |
| HE Dongpo,ZHOU Yongshui,ZHOU Wenyu,WANG Yuetong,WAN Chao |
| (Guizhou Meteorological Observatory, Guiyang 550002 , China;Guizhou Climate Center, Guiyang 550002 , China) |
| Abstract: |
| Based on the Wuchuan C-band dual-polarization radar and conventional data, this paper analyzed the cause and polarization parameter characteristics of a hail weather on March 30, 2021 in northwest Guizhou. The results show that, on that day, Guizhou is in the region of low level cyclonic shear and high level strong positive vorticity advection, and there is moderate to strong vertical wind shear in the northeast of Guizhou, and it is found that the intersection of dry tongues and ground convergence line is beneficial to stimulate strong updraft. In the strong echo mature stage, the maximum horizontal reflectance factor reaches 70 dBz, and the phenomena of hook echo, three-body scattering spike, bounded weak echo region and echo overhang appear. Polarization parameter analysis results show that ZH value was above 60 dBz and ZDR value was lower in -2~1.75 dB when hail occurred in this process. For wet hail, ZDR value was higher in 3~6 dB and KDP value was about 0 dB. With heavy precipitation, KDP value was higher in 2~6 °/km and CC value was lower in 0.85~0.93. ZDR column and KDP column with strong updraft appeared above 0 ℃ wet bulb height. The three-body scattering spike is well reflected in ZDR and CC plots, and the non-uniform beam filling phenomenon also appears in CC plots. |
| Key words: C-band dual-polarization radar； hail； dry tongue |
