双线偏振雷达在一次强降雹过程中的初步应用

Preliminary application of dual-polarization weather radar in a severe hail event

利用北京首都国际机场C波段双线偏振多普勒天气雷达和NECP再分析资料,分析了北京地区2008年6月23日降雹天气过程背景及双线偏振多普勒雷达产品的演变特征。通过对雷达差分反射率因子ZDR、单位差分传播相移KDP、相关系数ρHV等偏振参数的具体分析,总结出偏振雷达观测冰雹云的一些特征:雷达强度图中出现较强回波且高度较高,ZDR趋于零,ρHV、KDP比其周围数值忽然减小。此外,还分析了KDP、ρHV在辨别虚假回波和判断回波发展中的作用。上述研究对于提高双线偏振天气雷达在强对流灾害天气监测预警、防雹减灾以及航空安全等方面应用具有一定参考意义。

In the paper, we analyzed the environmental condition of the hailstorm in Beijing region on 23 June 2008 and the evolution char- acteristics of weather radar products by using the C band dual-polarization weather radar and NECP data. By detailed analysis of the polariza- tion parameters （ZOR,pHV,KDp）, some characteristics of hail clouds were summarized as follows. Strong echo occurred in the radar reflectivity map at high altitude, ZDR tended to be zero, and pHV and KDP suddenly decreased compared to values at the surrounding areas. In addition, the role of KDP and psv played in distinguishing false echoes and judging echo development was analyzed. The above study is valuable in improving the application of the dual-polarization weather radar in strong convective severe weather monitoring and forecast, hail disaster mitigation, aviation security, etc.