雨滴轴比订正对雷达参量及其关系的影响研究  

Influence of the Raindrop Axis Ratio on Radar Parameters and Their Relationships

作　　者：杨加艳[1,2,3] 肖辉[1] 李培仁[4] 肖稳安[3] 

机构地区：[1]中国科学院大气物理研究所云降水物理与强风暴实验室,北京100029 [2]湖南省防雷中心,长沙410007 [3]南京信息工程大学,南京210044 [4]山西省人工降雨防雹办公室,太原030002

出　　处：《气候与环境研究》2012年第1期29-36,共8页Climatic and Environmental Research

基　　金：国家自然科学基金资助项目40875080;国家科技支撑计划项目2006BAC12B01-01;公益性行业科研专项GYHY200806014;中国气象局与吉林省人民政府人工影响天气联合开放实验室开放课题0603

摘　　要：利用Parsivel雨滴谱仪在山西祁县、介休两地2008年7、8月观测的数据资料,对比分析了两地的总雨滴谱样本特征和雷达参量的分布概率,研究了雨滴轴比订正对降雨率R、雨滴含水量W和反射率因子Z计算的影响,结果表明雨滴轴比对雷达参量影响不可忽略。雨滴轴比订正效果随着R的增大而增大,当R>5mm·h-1时,轴比订正效果明显,而因Z正比于尺度D的6次方,其订正效果更加明显。最后,在雨滴轴比订正基础上给出两地的Z-R关系,同时确定了未经过轴比订正的反射率因子Znoncorr与订正后的降雨率Rcorr之间的Znoncorr-Rcorr关系,以及反射率因子Z与雨水含量W的Z-W关系,为当地雷达定量测量降水、深入研究云降水形成的微物理过程和雷电对区域降水的影响等提供了科学依据。Based on the observational data of raindrop size distributions （DSDs） from Parsivel optical disdrometers in Qixian and Jiexiu of Shanxi Province during the period of July and August 2008, a contrast about the characteristics of DSDs and the statistical probability of radar parameters are provided. And then, the dependences of rainfall R and rainwater content W related with reflectivity Z upon axis ratio are discussed. It shows that as the rainfall （R） increases, the corrected R is improved, especially when R〉5 mm·h^-1. As reflectivity Z is proportional to the 6th power of diameter （D）, the corrected reflectivity （Zcorr） is changed much more quickly. At last, on the basis of axis ratio, the Znoncorr-Rcorr, relationship and the refleetivity Z and rainwater content W relationship （Z- W） offer a scien- tific ground for radar measurement of precipitation and a deep-going way research on cloud micro-physical processes and the effects of thunder-lightning on regional precipitation is determined.

关 键 词：雨滴谱 轴比 Z—R关系 雨水含量 

分 类 号：P412.25[天文地球—大气科学及气象学]