基于单站CAPPI格点数据的相邻天气雷达均一性评估系统研究

基于经过严格质量控制后的单站CAPPI格点数据,对相邻天气雷达观测重叠区域内等距离线上的回波强度一致性状况进行研究,根据雷达不同探测距离、不同海拔高度、不同降水强度等因素编制相邻雷达自动配对程序和等高面自动选择程序,建立了相邻天气雷达均一性算法。制定了适合我国天气雷达回波观测差异特征的均一性评估的3类标准(可信、可疑和疑误),并给出了评估标准的满足条件,从而建立了全国天气雷达均一性实时评估系统。从评估效果来看,均一性评估系统能够实时高效检测出全国不同波段、不同型号以及不同省份相邻雷达之间的回波一致性状况,并给出评估结果;对浙江、福建、广东3省雷达一次降水过程的均一性评估,发现参与评估的27部S波段雷达整体可信率为85.19%,可疑率为11.11%,疑误率为3.7%,成功检测出雷达回波强度偏低、波束阻挡以及电磁干扰等问题;对临沂站雷达回波均一性分析,评估系统能及时报警,检测出该站雷达回波位置指向存在偏差,天线方位顺时针偏移16.88°,缩短了故障发现时间。

Research on Homogeneity Evaluation System of Neighboring Weather Radars Based on Single-Station CAPPI Grid Data

Based on the single-station CAPPI grid data after strict quality control,this paper studies the echo intensity consistency on the equidistant line in the overlapping area of adjacent weather radar observations.According to the elements of radar detection coverage,altitude and precipitation intensity,the automatic matching program of adjacent radar and the automatic selection program of contour plane are compiled,and the homogeneity algorithm of adjacent weather radar is established.Then,three kinds of criteria for evaluating the homogeneity of weather radar echo observation differences in China are formulated,which are credible,suspicious and false,and also the conditions for meeting the evaluation criteria are given.A national real-time weather radar homogeneity evaluation system is successfully established.The evaluation results show that the homogeneity evaluation system can detect the echo consistency of different bands,different radar models and adjacent radars in different provinces in real time and efficiently,and give the evaluation results.By evaluating the homogeneity of one-hour precipitation process of radar in Zhejiang,Fujian and Guangdong Provinces,27 S-band radars participated in the evaluation.The overall credibility rate of the 27 radars was 85.19%,the suspicious rate was 11.11%and the suspicious error rate was 3.7%.In addition,the problems of low radar echo intensity,beam blocking and electromagnetic interference are successfully detected.The uniformity analysis of radar echo at Linyi Station shows that the evaluation system can alarm in time,detect the deviation of radar echo position pointing at Linyi Station,and the azimuth of antenna shifts clockwise by 16.88°,which shortens the fault detection time.