雷达回波垂直廓线及其生成方法  

Vertical Profile of Radar Echo and Its Deteermination Methods

作　　者：吴翠红[1] 万玉发[2] 吴涛[3] 金鸿祥[4] 

机构地区：[1]南京大学大气科学系,南京210093 [2]中国气象局武汉暴雨研究所,武汉430074 [3]湖北省十堰市气象局,十堰442000 [4]武汉中心气象台,武汉430074

出　　处：《应用气象学报》2006年第2期232-239,共8页Journal of Applied Meteorological Science

基　　金：湖北省科技攻关计划课题(2004AA306B01);湖北省国际科技合作课题(2005CA012);湖北省气象局科技发展基金项目(2003ZZ01)共同资助。

摘　　要：研究雷达回波Z(R)垂直廓线VPR有两个重要内容:一是VPR的生成方法,二是用VPR订正雷达估算降水的技术。在简要比较现有生成方法———参数法、平均法和识别法的主要特点后,认为平均垂直廓线MVPR具有简便、实用的优点。文章着重对MVPR的生成方法作了细致的探讨,形成了4种生成算法,并作了比较;展示了各种生成参数对MVPR的不同作用,并简要介绍了一个应用程序框图。对两个降水实例实施订正后初步评估表明,用MVPR订正雷达估算降水可使评估因子R/G从0.84(0.86)提高到0.93(0.97),而绝对误差率则下降4%。Radar beam＇s lifting and widening in the distance and the vertical nonuniformity of the natural distribution of water content in the atmosphere are important factors of radar detecting rainfall errors. During 1980s-1990s, the importance of vertical profile of reflectivity （VPR） to radar detecting rainfall is emphasized and the study on the VPR technology is conducted. There are two major aspects on the researches of VPR, one is the determination method of VPR, the other is the technique to correct radar precipitation estimation. After comparing the major features of three existing determination methods, i. e. , parameterization, averaging and identification, it is found that the mean vertical profile of reflectivity （MVPR） has the advantage of simplicity and utility. Four algorithms of MVPR are obtained and compared with emphasis on investigating the determination method for mean vertical profile （MVPR） ; and the different functions of determining parameters, especially for MVPR, are demonstrated. Results show that the R/G ratio can be enhanced from 0.84（0.86） to 0.93（0.97） and the AD of radar rainfall estimation can decrease by 4 % after the MVPR correction in the two precipitation CaSeS. Among the four algorithms of MVPR, Mll is the best one in which the ratio profile takes the near groundlevel as the datum plane so that the feasibility of radar precipitation correction can be assured, and it has better representation owing to consideration of the same weighing of each bin in domain D. The MVPR algorithms relate to 8 attribute parameters, of which some values exert significant effect on the quality of MVPR. For example, the initial distance Ds in domain D obviously affects the profile shape below 1 km, therefore 1-5 km should be adopted; the distance outside DO domain D plays its role from near ground-level to 6 km and the smaller DO, the smaller the more smoothing due to the beam widening, so 40-50 km should be adopted; the smaller the value of the vertical piecewise-height Ah, the mor

关 键 词：雷达回波垂直廓线 VPR生成方法 降水订正 

分 类 号：P412.25[天文地球—大气科学及气象学]