超折射回波自动探测算法在临近预报中的应用  

Application of an automated algorithm to remove anomalous propagation ground returns in nowcasting

作　　者：庄旭东[1] 胡胜[1] 徐芬[2] 胡东明[1] 梁巧倩[1] 

机构地区：[1]广州中心气象台,广州510080 [2]江苏省气象局,南京210008

出　　处：《气象科学》2009年第2期241-245,共5页Journal of the Meteorological Sciences

基　　金：广州市科技攻关项目(06A13043333);广东省气象局气象科技项目(2007E08)

摘　　要：本文介绍了一种对雷达基资料进行处理的超折射回波自动探测算法,该算法针对超折射回波的特征,利用多普勒径向速度中值、反射率因子水平突变率和反射率因子垂直梯度,在雷达体扫描最底层PPI上逐库处理,以识别超折射回波。在北京奥运会天气预报示范项目测试期间,超折射回波自动探测算法在"葡萄—雨燕"临近预报系统中得到应用,结果表明:该算法能够剔除天津雷达探测到的大量的超折射回波,尤其是反射率因子水平突变率参数和反射率因子垂直梯度能够有效的分离出与降水回波混合在一起的超折射回波;进而,在定量降水产品中运用该算法的处理结果,可以明显的改善其精度。In this paper an automated procedure has been developed that makes use of the median radial velocity, SPIN and the vertical extent of reflectivity to remove anomalous propagation ground returns. During the trial of B08FDP in 2007, the algorithm has been applied in the ＂Grapes - Swift＂. It removes most of AP clutters detected by Tianjin radar, and appears to work well in situation where AP clutters are embedded within precipitation echoes. Moreover, one hour quantitative precipitation forecast is improved by using the algorithm.

关 键 词：超折射回波 临近预报 垂直梯度 

分 类 号：P412.25[天文地球—大气科学及气象学]