Wind profiler radar (WPR) is mainly used to detect atmospheric wind fields based on electromagnetic scattering of atmospheric turbulence.WPR can simultaneously receive the scattered echo of atmospheric turbulence and precipitation particles during precipitation.Therefore,the power spectrum of WPR in precipitation contains both the spectrum of atmosphere and the spectrum of precipitation.In this situation,the information of atmospheric vertical motion is contaminated by the movement of raindrops,leading to errors in subsequent retrieval of atmospheric motions.However,millimeter-wave cloud radar can only detect raindrops and cloudwater drops during precipitation.This paper aims to suppress the precipitation interference on WPR based on millimeter-wave radar observations.Verification and analysis of the spectrum is conducted for a classical weak precipitation case in the present study.Comparison and analysis of two-peak velocity,modified velocity and original WPR velocity show that the method can successfully eliminate effects of precipitation on atmospheric velocity retrieval during weak precipitation.It can also obtain turbulence velocity from WPR when turbulence echo is quite faint.However,the attenuation of cloud radar during precipitation will have negative influences on the results of the method,which makes it only suitable for weak precipitation events and at lower levels at present.%风廓线雷达主要是利用大气湍流对电磁波的散射作用,在晴空条件下对大气风场等进行探测.在降水天气下,风廓线雷达能同时接收到大气湍流回波和雨滴的散射回波信号,其探测到的回波功率谱中降水信号谱和大气湍流信号谱叠加在一起,使得大气的运动被雨滴的运动信息所掩盖,给后续的大气风场反演带来误差.而毫米波云雷达在降水天气下仅能探测到云雨粒子的回波而无法探测到大气湍流回波,基于这一差异结合毫米波云雷达资料对风廓线雷达功率谱数据进行订正,剔除其中的降水回波信息,进而获取正确的大气运动垂直速度.通过一次典型弱降水天气过程的雷达资料对该方法进行了可行性验证,并将计算得出的大气垂直速度与传统双峰法提取的大气运动垂直速度及原始风廓线雷达垂直速度进行了对比分析,显示在弱降水天气下该方法能有效消除降水对风廓线雷达垂直速度测量的影响,提高弱降水天气下测速准确率,并且在湍流谱极其微弱的情况下该方法也能准确地获取到大气运动垂直速度信息.但是云雷达回波在降水时会有衰减,虽然是弱降水也会导致在高层距离库上的订正效果变差,故目前只适用于弱降水时低距库处的降水订正.
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