C-BAND DUAL-POLARIZATION DOPPLER WEATHER RADAR DATA ANALYSIS AND ITS APPLICATION IN QUANTITATIVE PRECIPITATION ESTIMATION
-
摘要: 基于南京信息工程大学C波段双线偏振多普勒天气雷达(NUIST-CDP)的观测资料,结合南京龙王山SA天气雷达数据、南京信息工程大学大气综合观测基地的OTT Parsivel雨滴谱仪数据、南京市地面雨量计数据,分析NUIST-CDP探测资料的质量及定量降水估计(QPE)精度情况。将NUIST-CDP与SA雷达的回波强度数据进行了对比,发现NUIST-CDP回波强度偏弱;将滴谱仪上方NUIST-CDP测量的反射率因子ZH、差分反射率因子ZDR与滴谱仪数据对比,雷达参量ZH、ZDR与滴谱仪数据变化趋势一致,但整体略偏小;比较差分传播相移率KDP与ZH的变化情况,由差分传播相移ΦDP经最小二乘法计算得到的KDP与ZH数据一致性很好。利用南京地区2015年夏季(5—8月)收集的滴谱数据计算偏振雷达参数,拟合测雨方程,进行两次降水过程个例的QPE分析,并与南京地区雨量计数据进行了对比。结果表明:R(KDP)测雨精度最高,R(KDP,ZDR)次之,使用偏振参量能明显提高降雨估算精度;R(ZH)、R(ZH,ZDR)方法测雨反演结果低于地面雨量计雨量值,且低于SA雷达反演结果。
-
关键词:
- C波段双线偏振多普勒天气雷达 /
- 雨滴谱 /
- 数据质量分析 /
- 定量降水估计(QPE)
Abstract: Based on observation data of two precipitation events in Nanjing on July 2015, the data quality of a C-band dual-linear polarimetric weather radar in Nanjing University of Information Science and Technology (NUSIT-CDP) and its capability of quantitative precipitation estimation (QPE) are presented, using the data from an SA weather radar on Longwang Mountain in Nanjing, an OTT Parsivel disdrometer at a NUIST student observing station, and rain gauges of Nanjing. Compared with the data from the SA radar, the reflectivity factor ZH of NUIST-CDP is smaller due to attenuation. The data of ZH and differential reflectivity ZDR observed by NUIST-CDP, in contrast with the data from the disdrometer, agree well as a whole but are slightly smaller. In addition, the variation trends of ZDR and KDP are consistent with that of ZH, which can effectively present the characteristics of precipitation particles. By using raindrop size distribution data of Nanjing in the summer of 2015 from OTT Parsival, the rainfall estimation equations are fitted, and the validity of the rainfall estimation are tested by comparing the rainfall retrieving results with the rain gauge data. The findings show that the rain rate estimated from R(KDP) is most accurate and R(ZH, ZDR) is less accurate, which means that using dual polarization parameters can improve the rainfall estimation. The rain rate estimated from R (ZH) and R (ZH, ZDR) of the C-band radar are much less than the rain gauge result, and less than the results retrieved with the SA radar. -
表 1 测雨公式拟合结果测雨公式
测雨公式 ax bx cx 相关系数 方差/(mm/h) R1=a1×ZHb1 0.051 8 0.604 2 \ 0.953 9 5.376 9 R2=a2×ZHb2×ZDRc2 0.032 4 0.657 3 -0.211 9 0.969 4 2.265 6 R3=a3×KDPb3 21.132 4 0.910 6 \ 0.994 6 0.634 7 R4=a4×ZDRb4×KDPc4 21.489 4 -0.074 8 0.936 5 0.996 2 0.316 4 表 2 2015年6月2—3日雷达反演降水与雨量计测量结果的统计比较测雨公式
测雨公式 相关系数 平均偏差/(mm/h) 均方根误差/(mm/h) R(ZH) 0.667 7 -6.077 8 7.538 6 R(ZH, ZDR) 0.665 9 -6.159 3 7.564 7 R(KDP) 0.792 6 -1.115 1 4.769 3 R(ZDR, KDP) 0.791 8 -1.262 6 4.733 1 SA雷达R(Z) 0.655 8 -3.226 1 6.149 9 表 3 2015年6月26—28日雷达反演降水与雨量计测量结果的统计比较
测雨公式 相关系数 平均偏差/(mm/h) 均方根误差/(mm/h) R(ZH) 0.618 3 -5.053 9 7.256 9 R(ZH, ZDR) 0.603 4 -5.910 7 7.957 0 R(KDP) 0.703 7 -1.383 8 4.676 6 R(ZDR, KDP) 0.699 8 -1.968 4 4.856 2 SA雷达R(Z) 0.549 0 -2.459 8 5.757 4 -
[1] BRINGI V N, CHANDRASEKAR V. Polarimetric Doppler weather radar: principles and applications[M]. Cambridge: Cambridge University Press, 2001. [2] ZRNIC D S, RYZHKOV A. Advantages of rain measurements using specific differential phase[J]. J Atmos Oceanic Technol, 1996, 13(2): 454-464. [3] RYZHKOV A V, ZRNIC D S, BURGESS D, et al. Observation and classification of echoes with the polarimetric WSR-88D radar[R]. Report of National Severe Storms Laboratory, Norman, Oklahoma, 2003: 19-26. [4] 刘黎平, 葛润生, 张沛源.双线偏振多普勒天气雷达遥测降水强度和液态含水量的方法和精度研究[J].大气科学, 2002, 26(5):709-720. [5] 高晓荣, 梁建茵, 李春晖.雷达定量降水估计技术及效果评估[J].热带气象学报, 2012, 28(1): 77-88. [6] 高玉芳, 陈耀登, DAVID G, 等. JOPLE算法结合双偏振雷达在不同降水过程中的测雨效果分析[J].热带气象学报, 2014, 30(2): 361-367. [7] 郭丽君, 王振会, 张培昌, 等.扁椭球雨滴后向散射的Gans理论和T矩阵差异对雷达探测释义的影响[J].热带气象学报, 2014, 30(4): 755-762. [8] 杜牧云, 刘黎平, 胡志群, 等.双线偏振多普勒雷达资料质量分析[J].气象学报, 2013, 71(1): 146-158 [9] 胡志群, 刘黎平, 王丽荣. C波段双线偏振雷达误差分析及降水估测精度研究[C]//第26届中国气象学会年会, 杭州, 2009. [10] 刘黎平, 钱永甫, 王致君.用双线偏振雷达研究云内降水粒子相态及尺度的空间分布[J].气象学报, 1996, 54(5): 590-598. [11] MATROSOV S Y, CIFELLI R, PATRICK C, et al. A comparative study of rainfall retrievals based on specific differential phase shifts at X- and S-band radar frequencies[J]. J Atmos Oceanic Technol, 2006, 23(7): 952-963. [12] RYZHKOV A V, SCHUUR T J, BURGESS D W, et al. The Joint polarization experiment: polarimetric rainfall measurements and hydrometeor classification[J]. Bull Amer Meteor Soc, 2005, 86(6): 809-824. [13] 曹俊武, 刘黎平, 陈晓辉, 等. 3836C波段双线偏振多普勒雷达及其在一次降水过程中的应用研究[J].应用气象学报, 2006, 17(2):192-201. [14] 马学谦, 董万胜, 楚荣忠, 等. X波段双偏振多普勒天气雷达降水估算试验[J].高原气象, 2008, 27(2): 382-391. [15] 王建林, 刘黎平, 曹俊武.双线偏振多普勒雷达估算降水方法的比较研究[J].气象, 2005, 31(8): 25-41. [16] 赵果, 楚荣忠, 张彤, 等.偏振多普勒雷达定量测量降雨精度的改进[J].高原气象, 2011, 30(2): 498-507. [17] 吴林林, 刘黎平, 袁野, 等. C波段车载双偏振雷达ZDR资料处理方法研究[J].高原气象, 2015, 34(1): 279-287. [18] 曹杨, 苏德斌, 周筠珺, 等. C波段双线偏振多普勒雷达差分相位质量分析[J].高原气象, 2016, 35(2): 548-559. [19] 肖艳娇, 王斌, 陈晓辉, 等.移动X波段双线偏振多普勒天气雷达差分相位数据质量控制[J].高原气象, 2012, 31(1): 223-230. [20] 魏庆, 胡志群, 刘黎平, 等. C波段偏振雷达数据预处理及在降水估计中的应用[J].高原气象, 2016, 35(1): 231-243. [21] 楚志刚, 胡汉峰, 黄兴友, 等.南京信息工程大学窄波束C波段双偏振多普勒天气雷达及其探测能力分析[J].高原气象, 2017, 36(4): 1 072-1 081. [22] 姚晓娟. NUIST-C波段双线偏振多普勒雷达资料质量控制及回波特征分析[D].南京: 南京信息工程大学, 2016. [23] 贺金瑞. C波段双线偏振雷达衰减订正比对试验分析[D].南京: 南京信息工程大学, 2016. [24] VIVEKANANDAN J, ZHANG G F, BRANDES E. Polarimetric radar estimators based on a constrained gamma drop size distribution model[J]. J Appl Meteor, 2004, 43(2): 217-230. [25] ZHANG G F, VIVEKANANDAN J, BRANDES E. A method for estimating rain rate and drop size distribution from polarimetric radar messurements[J]. IEEE Trans Geosci Remote Sens, 2001, 39(4): 830-841. [26] BRANDES E A, ZHANG G F, VIVEKANANDAN J. Experiments in rainfall estimation with a polarimetric radar in a subtropical environment[J]. J Appl Meteor, 2002, 41(6): 674-685. [27] 胡鹏, 胡明宝, 张柽柽, 等. S波段双线偏振雷达KDP参数计算的初步研究[J].气象与环境学报, 2012, 28(1): 77-81. -
下载:
粤公网安备 4401069904700003号