一次海面降雪的双线偏振多普勒雷达回波特征分析

Characteristics of sea clutter and snowfall echoes from dual linear polarization Doppler radar

以X波段双线偏振多普勒天气雷达在葫芦岛探测到的2004年4月1日的一次海面降雪过程为例，概述了雷达主要性能参数。通过分析雷达二次产品开发平台运行后得到的强度、速度、谱宽和双线偏振差分反射率等产品，探讨了海面降雪和海杂波Z值及差分反射率因子zDR的取值大小及空间变化特征。结果表明：雪花降落过程中，ZDR值由正值逐渐转变到为-0.5～0.5dB，且Z值随高度降低而增大，而海杂波Z及ZDR值空间变率不大。

Based on a sea surface snowfall process explored by X-band dual linear polarization Doppler radar in Huludao on 1st April 2004, the main parameters of radar were summarized. The second production development platform was introduced, and the intensity, speed, spectrum width and dual linear polarization differential reflectivity were analyzed. The value ranges and spatial characteristics of sea surface snowfall, sea clutter reflectivity （Z） and differential reflectivity （ZDR） were discussed. The results indicated that the differential reflectivity （ZDR） turned to the negative value （ - 0.5- 0.5 dB） during sea surface snowfall. The sea clutter reflectivity （Z） increased with the height decrease, while the spatial variabilities of sea clutter reflectivity （Z） and differential reflectivity （ZDR） were small.