基于激光雷达和毫米波云雷达的卷云特性分析

使用美国ARM计划安徽省寿县站2008年的微脉冲激光雷达和毫米波雷达的观测数据对寿县上空卷云的宏观物理特性进行了分析,联合两种雷达观测卷云扩大了卷云的边界轮廓,得到更为全面的卷云信息,结果表明了联合激光雷达和毫米波雷达观测卷云的必要性。在此基础上,对观测期间寿县上空的卷云个例进行统计分析,结果显示:卷云过程的平均云底高度分布在5~10km,其中6~7km范围所占的频率最大;平均云厚的分布范围为0.25~5km,其中90.8%分布在0.5~2.5km;卷云过程持续时间总体上随着持续时间的增大呈减少的趋势,持续时间最长为35.5h,平均为3.6h,持续时间小于5h的卷云过程占82.5%。

Analysis of cirrus properties based on micro-pulse lidar and millimeter wave cloud radar

Macro-physical characteristics of cirrus above Shouxian were studied using data from micro-pulse lidar (MPL ) and millimeter wave cloud radar (MWCR) on mobile facilities of atmospheric radiation measurement (ARM). Enlarged profile and comprehensive information of cirrus were retrieved when combined data of these two facilities were used, which indicated the necessity of joint observation. On this basis, statistical analysis was performed using cirrus cases occurred above Shouxian during observation period. The results showed that the averaged height of cloud base ranged from 5 to 10 km, and cirrus with a base height of 6-11 km had higher occurrence frequency. The averaged thickness of cloud ranged from 0.25 to 5 km, among which cirrus with a thickness of 0.5-2.5 km accounted for 90.8%. The statistical results also showed the occurrence frequency of cirrus process reduced with the increase of duration, the maximum and mean duration were 35.5 h and 3.6 h respectively, and cirrus with duration less than 5 h accounted for 82.5%.