合肥地区一次小雨过程的W波段云雷达的云物理特征分析

Analysis on Cloud Physical Characteristics of a Light Rain Process in Hefei Detected by W-Band Cloud Radar

利用我国自己研制的W波段云雷达地基探测资料,分析了合肥一次小雨云系的微物理过程,然后利用两个不同地区的地基及机载探测资料,初步反演了水云及卷云的微物理参数。结果表明:(1)回波强度增大,多普勒速度、线性退极化比(LDR)、谱宽激增的地方为融化层顶,根据LDR亮带可初步判定融化层的厚度;(2)利用经验关系法,对卷云冰水含量和水云的液态水含量进行了反演,利用推导的公式反演得到冰晶云云粒子的有效半径;(3)利用逐库订正法对水云的回波强度进行订正,得到了衰减订正后的液态水含量,减小了反演误差。

Using the data detected by the W-band ground radar developed by China, the physical process of a cloud system with light rain in Hefei was analyzed, and the microphysical parameters in the water cloud and cirrus cloud were retrieved preliminarily based on the data from two different regions detected by the ground and airborne W-band radars. The results showed that： （1） The corresponding height where the echo intensity increased, and the Doppler velocity, linear depolarization ratio （LDR） and spectral width suddenly increased was the top of melting layer, then the thickness of melting layer was initially estimated according the LDR bright band. （2） Using empirical relations, the ice and liquid water content of cirrus cloud and water cloud were retrieved, and the effective radius of ice crystal cloud particles were also ob tained using the derived formula. （3） Using bin by-bin correction method in the groups, the echo intensity of water cloud was corrected, then the liquid water content was retrieved based on the corrected echo in tensitv, so the retrieval errors were reduced.