一次早春冰雹天气过程的双偏振相控阵雷达回波特征分析
Analysis of the Characteristics of X-Band Dual-Polarization and Phased-Array Weather Radar during a Hail Weather Process in Early Spring

本文利用成都市X波段双偏振相控阵天气雷达资料，对2021年3月6日成都市一次局地冰雹天气过程进行了分析。结果表明，X波段双偏振相控阵天气雷达提供的高时空分辨率雷达产品能够更精细地展现冰雹天气的演变过程；小的Z_DR值和高的强度Z对应的是纯冰雹区，一旦冰雹开始融化，Z_DR的值也会随着融化而变大；利用模糊逻辑算法识别粒子相态的水凝物分类产品能够直观地给出冰雹云的垂直结构图，从而分析出冰雹的降落状态。雷达回波演变过程和雷达水凝物分类产品资料分析结合实况证明对流单体合并的尾声阶段开始降雹，且对流单体的合并区域是冰雹的主要落区。此外，早春的此次冰雹天气过程回波顶高最大值在5 km左右，有别于夏季的冰雹天气，需引起重视；垂直液态水含量(VIL)的跃增是降雹开始前的一个重要指征。
Based on the data of X-band dual-polarization and phased-array weather radar in Chengdu, a local hail process on March 6, 2021 was analyzed. The results showed that the X-band dual-polarization and phased-array weather radar could show the evolution of the hail weather process more precisely. Low Z_DR associated with high Z is a certain indication of dry hail. Once hail starts melting, Z_DR increases as hail progressively melts. The hydrometeor classification product which uses the fuzzy logic algorithm to identify hydrometeor particles could give the vertical structure of hail clouds intuitively, and then we could get the falling state of hail. The evolution process of radar echo and the analysis of radar hydrometeor classification combining with the hail falling fact provided by the local weather modification workers proved that hail began to fall in the final stage of convective monomer merging, and the merging area of convection monomer was the main hail falling area. In addition, the maximum echo height of this hail process in early spring was about 5 km, which was different from the hail weather process in summer, so it needed more attention. The jump of vertical integrated liquid water content (VIL) was an important indication before the hailstorms began falling.