X波段双偏振雷达反演雨滴谱方法研究  

Retrieval of Raindrop Size Distribution by X-Band Dual-Polarization Radar

作　　者：李宗飞[1,2,3] 肖辉[2] 姚振东[1] 冯亮[2] 

机构地区：[1]成都信息工程学院,成都610225 [2]中国科学院大气物理研究所云降水物理与强风暴重点实验室,北京100029 [3]天津市气象信息中心,天津300000

出　　处：《气候与环境研究》2015年第3期285-295,共11页Climatic and Environmental Research

基　　金：国家重点基础研究发展计划项目2014CB441403、2013CB430105;国家自然科学基金资助项目41205099;贵州省黔科合项目G[2013]4001;公益性行业(气象)科研专项GYHY201006031

摘　　要：X波段双偏振雷达观测参数能够完成雨滴谱反演,但是由于X波段雷达波长较短,降水观测时存在较大的衰减,本文采用自适应约束算法进行反射率和差分反射的衰减订正。通过对雨滴模型的散射模拟以及对雨滴谱进行Gamma谱拟合,建立了雨滴谱参数与双偏振雷达目标参数之间的函数关系和雨滴谱参数相互之间的关系,用于进行雨滴谱反演。将雨衰减订正前后的雷达目标参数进行雨滴谱反演并与实测雨滴谱进行对比,结果表明,所建立的X波段双偏振雷达反演雨滴谱方法能够较好地反演雨滴谱,并且经过订正后反演得到的雨滴谱在浓度、尺度和谱形上都优于订正前的反演结果,通过对距离高度扫描和平面位置扫描数据进行雨滴谱反演,可以得到雨滴谱参数的垂直结构和水平分布,可用以进行降水分析。Dual-polarization radar is able to effectively retrieve raindrop size distribution（DSD）. However, as the wavelength of X-band radar is short, larger rain attenuation is observed. This paper makes corrections in reflectivity and differential reflectivity using the self-consistent algorithm with constraints. By conducting scattering simulation and gamma spectrum fitting, the functions of dual-polarization radar and raindrop spectrum parameters are examined to determine the internal relationship of raindrop spectrum parameters for retrieval of DSD. The observed DSD is compared with DSD retrieved by radar and corrected radar parameters. The results show that the method established in this paper is effective for retrieving DSD. The concentration, scale, and spectral shape are improved by using corrected data. Moreover, the vertical structure and horizontal distribution of DSD parameters can be obtained by using range-height indicator and Plan Position Indicator data to retrieve the DSD. Therefore, this method can be used to effectively analyze precipitation.

关 键 词：双偏振雷达 衰减订正 雨滴谱反演 GAMMA分布 

分 类 号：P412[天文地球—大气科学及气象学]