摘要: |
利用习水双偏振雷达对2021年5月2日发生在贵州西北部的一次冰雹、短时强降水过程进行分析,结果表明:双偏振雷达能够很好区分出冰雹和短时强降水,并可以分析出冰雹相态演变:高空出现明显的冰雹特征(差分反射率因子Zdr、差分相移率Kdp小于0 dB,相关系数CC为0.9~0.95),随着高度降低Zdr和Kdp从负值向正值转变,CC增加到0.95左右,表明冰雹在下落过程中融化为包裹着水膜的小冰雹并伴随降水,这与地面观测事实一致。观测到CC谷、Zdr弧、Zdr柱、Kdp柱和典型的三体散射双偏振特征,这些特征对雹暴的演变有指示作用。短时强降水回波的Zdr和Kdp随反射率因子强度的增大而增大,CC>0.95,Kdp大值区能更好的指示出短时强降水的位置。 |
关键词: 双偏振雷达;冰雹;短时强降水 |
DOI: |
投稿时间:2021-12-24修订日期:2022-02-10 |
基金项目:国家自然科学基金项目(面上项目,重点项目,重大项目) |
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Application of Dual-Polarization Radar to a Strong Convection Weather Case in Guizhou |
LI Li,ZHOU Yongshui,GU Tianhong,YAO Lang |
(Guizhou Meteorological Observatory;Bijie Meteorological Observatory) |
Abstract: |
Based on Xishui dual-polarization radar detection data, a hailstorm and short-term severe rainfall occurred in northwestern Guizhou on May 2, 2021 were analyzed. The results show that the hail and short-term severe rainfall can be identified by dual-polarization radar well. We analyze the hail phase state evolution. The obvious hail features (differential reflectivity Zdr and specific differential phase Kdp < 0, co-polar correlation coefficient CC is 0.9~0.95) occurs at high level. As the height decreases, the values of Zdr and Kdp change from negative to positive and CC increased to about 0.95, which indicate that the hails melt into big raindrops or outsourcing water film hails. This is consistent with the ground observation facts. CC hole, Zdr and Kdp columns, three-body scatter signature are observed, which can indicate the hailstorm evolution. Zdr and Kdp of short-term severe rainfall increase with the intensity of reflectivity, and the value of CC is above 0.95. The large Kdp value can indicate short-term severe rainfall location well. |
Key words: Dual-polarization radar; Hail; Short-term severe rainfall |