毫米波雷达在台风外围云系研究中的应用

Application of Millimeter-Wave Radar in the Study of Typhoon Outer Rainbands

为评估台风条件下毫米波雷达的探测表现,利用上海2018年和2019年4个台风影响期间的毫米波雷达数据,结合雨滴谱仪、静止卫星、S波段天气雷达等资料,探讨了利用毫米波雷达研究台风外围云系的可能性。结果表明:毫米波雷达探测台风外围区域具有良好的性能,对于云降水结构的垂直探测具有一定应用潜力;在降水强度低于5 mm·h^(-1)时雷达对于云顶高度的探测较为准确;提出一种融化层亮带判别方法,亮带识别结果与探空观测一致。对比毫米波雷达与S波段天气雷达降水强度反演,结果显示利用毫米波雷达衰减特征能够实现降水强度廓线的反演,但需要对存在显著雨滴碰并增长的降水进行识别并订正,可为毫米波雷达探测台风外围云系提供参考依据。

In order to evaluate the performance of millimeter-wave radar in the case of typhoon,the millimeter-wave cloud radar data of Shanghai during the four typhoons in 2018 and 2019,and the data of disdrometer,satellite and S-band weather radar are studied to explore the feasibility of using the millimeter-wave radar to study the outer rainbands of typhoon.It is shown that the millimeter-wave radar has a good detection performance,and has certain application potential for detecting vertical structure of cloud and precipitation.Determination of cloud top height is more accurate when the rainfall rate is lower than 5 mm·h^(-1).A method for bright band determination is proposed,and the results of application are found to be in good agreement with the sounding.Comparison of the retrieval of rainfall intensity by millimeter-wave radar and S-band radar shows feasibility of retrieving rainfall rate profile by taking advantage of the millimeter-wave radar attenuation.In the situation of significant growth of raindrops,it is necessary to revise the retrieval algorithm.This research could provide a reference for millimeter-wave radar detection of typhoon outer rainbands.