X波段双线偏振雷达不同衰减订正方法对比及其对降水估测影响研究  

Comparison of different attenuation correction methods and their effects on estimated rainfall using X-band dual linear polarimetric radar.

作　　者：胡志群[1,2] 刘黎平[1] 楚荣忠[3] 金荣花 

机构地区：[1]中国气象科学研究院,灾害天气国家重点实验室,北京100081 [2]南京信息工程大学,南京210044 [3]中国科学院寒区旱区环境工程研究所,兰州730000 [4]国家气象中心,北京100081

出　　处：《气象学报》2008年第2期251-261,共11页Acta Meteorologica Sinica

基　　金：科技部科研院所技术开发研究专项“双线偏振雷达气象产品生成软件系统研制”;国家重大基础研究项目(2004CB418305)

摘　　要：文中分析了X波段双线偏振雷达衰减订正各种方法的特点,考虑到差传播相移率(KDP)作为衰减订正的一种有效途径,以及由于KDP值较小,数据质量不稳定,往往导致订正误差较大,因此提出了同时利用水平反射率因子ZH与KDP进行衰减订正的ZH-KDP综合法。基于同样的考虑,在随后利用ZH、KDP进行降水估测时,提出了ZH-KDP-R综合估测方法。利用中国科学院寒区旱区环境与工程研究所和成都锦江电子系统工程有限公司,在研制3.2cm波长同时收发式多普勒偏振天气雷达过程中,2005年8月在平凉外场试验取得的一批观测资料,对提出的衰减订正综合法及降水估测综合法的效果进行了分析检验,结果表明,ZH-KDP综合法对ZH、ZDR有稳定的订正效果,并且订正速度快,能够达到实时运行的要求。2005年8月11日15:08:03—22:05:46,间隔5—12min不等,雷达开机取得了连续的观测资料,通过对这次降水过程的对比分析表明,ZH-KDP-R综合估测法比单因子KDP-R法、Z-R关系法,适用估测的降水强度变化范围广,与自动雨量记的观测结果较为吻合。Z-R关系法中,利用订正后的ZH值,比利用订正前的ZH值,降水估测值与雨量记实测值的误差明显减小,说明衰减订正后的雷达数据质量有明显的改善。Except its smaller antenna, mobile convenience and low cost, X-band radar has a higher resolution than the S-band＇s, and C-band＇ s, and therefore can therefore detect more subtle microphysical processes information of clouds, raindrop, hail and hydrometeor etc. As an effective complementarity of new generation weather radar network, it can be widely applied to the monitoring and warning of disastrous weather such as heavy rain and hails, the operations guidance and effect evaluation of weather modification, and the managements of reservoir, urban area and aviation etc. , therefore, it has a huge potential in the remote sensing of clouds and precipitation and in nowcasting. Compared to ordinary Doppler weather radars, dual polarimetric radar have a very distinct advantage in the quantitative estimation of precipitation, however, the radar signal attenuation is an important shortcoming which hampers the wide application of X-Band radar, especially in precipitation estimate. Various kinds of signal attenuation correction methods for X- band dual linear polarimetric radar are analyzed, the specific differential phase shift KDp is considered as an effective approach on attenuation correction. However, the values of KDp for light rain are too small, which results in instable quality and larger error, there- fore, reflectivity and specific differential phase shift are combined together in the ZH-KDp method to correct the attenuation error. Based on the similar consideration, ZH-KDp-R combined technique is also suggested when ZH and KDp are used to estimate rainfall. During the development stage of the synchronous transmitting and receiving dual polarimetric Doppler weather radar with 3.2 cm wave length by the Cold and Arid Regions Environmental and Engineering Research Institute, Chinese Academy of Sciences and Jinjiang Electronic System Engineering Co. , Ltd. Chendu, a set of observational data were obtained in the field experiment in Pingliang in August 2005. By means of the set of observational data, the effect o

关 键 词：x波段双线偏振雷达 衰减订正 降水估测 

分 类 号：P412.25[天文地球—大气科学及气象学] P414.95