X波段双线偏振气象雷达反射率的衰减订正  

Attenuation Correction of Reflectivity for X-Band Dual-Polarization Radar

作　　者：毕永恒[1] 刘锦丽[1] 段树[1] 吕达仁[1] 苏德斌[1,2] 陈羿辰[1,2,3] 

机构地区：[1]中国科学院大气物理研究所,北京100029 [2]北京市气象局,北京100089 [3]成都信息工程学院,成都610225

出　　处：《大气科学》2012年第3期495-506,共12页Chinese Journal of Atmospheric Sciences

基　　金：国家自然科学基金资助项目40930949;40227001;中国科学院知识创新工程重要方向项目KZCX2-YW-206

摘　　要：X波段天气雷达的强衰减是影响其探测精度与应用推广的主要问题。本文旨在寻求适用于降水过程中对X波段双偏振雷达进行衰减订正的一种方法。在订正前先对雷达数据进行了质量控制和预处理;在分析了国内外已有订正方法的基础上,选择并改进了自适应约束算法作为雷达反射率进行衰减订正的方法;最后进行方法的效果验证。既对衰减订正前后反射率与同时段S波段雷达反射率作对比,又对偏振参数KDP～ZH、AH～ZH之间关系的变化进行分析,不仅如此,还直接与地面降水实况作比较等。分析表明,对X波段双线偏振雷达进行反射率衰减订正后的效果显著优于订正前,特别是,当存在较大范围(含对流型)降雨时,采用此种订正方法可以明显提高降水的估测精度。Strong attenuation in rain affects the detection accuracy and application of the X-band radar. This paper aims to seek a method of attenuation correction for X-band dual-polarization radar in precipitation. Before correction, the radar data are pre-processed with quality controll after analyzing all the methods from the past works, an attenuation correction algorithm is developed which is based on the self-consistent method with constraints; finally some validation methods are studied. Some comparisons are made between the corrected composite reflectivity of the X-band radar and a nearby S-band radar observed at the same time; moreover, the corrected relationships between KDe vs. ZH and AH vs. ZH are also similar to the theoretical values predicted by scattering simulation. In addition, the authors also compare the corrected reflectivity with the surface rain-gauge observations. The analysis results indicate that the corrected reflectivity is more significant than the uncorrected one; specially for the larger area of rainfall （including convective rainfall） using the above attenuation correction algorithm for X-band radar, rainfall amounts can be estimated with higher accuracy.

关 键 词：X波段双线偏振雷达 衰减订正 自适应约束算法 

分 类 号：P406[天文地球—大气科学及气象学]