天气雷达回波外推技术应用研究  

Study on Extrapolation Technique of Weather Radar Echo and Its Application to Nowcasting

作　　者：朱平[1] 李生辰[1] 肖建设 徐亮[1] 靳世强[1] 

机构地区：[1]青海省气象台,西宁810001 [2]青海省气象科研所

出　　处：《气象》2008年第7期3-9,I0001-I0004,共11页Meteorological Monthly

基　　金：中国气象局新技术推广项目(CMATG2007M43)资助

摘　　要：利用天气雷达体扫基数据,对其强度数据做了回波外推运算。在成熟的COTREC(Continuity of Tracking Radar Echo by Correlation vectors)和质心跟踪技术的基础上,运用傅立叶相位分析技术计算"亚像元"速度,得到外推后的回波数据和图像,根据Z-R关系得到外推回波的雨强分布。通过将计算与不计算"亚像元"速度的外推回波与实况回波、外推所得雨强分布与PUP的1小时降水量(OHP)产品和自动雨量站记录分别做比较分析,结果表明,通常计算"亚像元"速度的外推要比不计算的准确度更高,并且外推所得1小时降水量比OHP的可信度更大。在各种降水类型的天气过程中,对该技术进行了多次检验,结果证明是适用的,能对TREC技术起到一定改进作用,且其外推所得雨强分布在短时临近降水预报中具有一定的参考价值。The basal data of volume scanning of Doppler radar is extrapolated. Based on the ripe COTREC （Continuity of Tracking Radar Echo by Correlation vectors） and centroid tracking technique, the ＂sub-pixel＂ velocity is computed by Fourier phase analysis technique, so the echo data and its image are obtained through extrapolation. Furthermore, the distribution of precipitation intensity is worked out based on the Z-R formula. The extrapolated results with and without use of sub-pixel velocity are compared with actual intensity data of volume scanning, the distribution of precipitation and one hour precipitation （OHP） product of PUP in WSR-88D are compared with the data of automatic precipitation station records. The analysis results indicated that the accuracy of using sub-pixel velocity in extrapolation is higher than that of non-use, and the reliability of one hour precipitation through extrapolation is greater than the OHP of PUP. The extrapolation technique is tested in different kinds of weather process. The findings show that this technique is applicable, can improve the technique of TREC, and has some referenced value in nowcasting.

关 键 词：COTREC 傅立叶相位分析 质心跟踪 

分 类 号：P414.4[天文地球—大气科学及气象学] TN959.4[电子电信—信号与信息处理]