毫米波雷达和激光雷达探测云边界的对比分析

为了探测云边界,采用毫米波雷达(MMCR)和微脉冲激光雷达(MPL)联合观测的方法,观测了层积云、高层云、高积云和卷积云个例,并对比分析了两部雷达探测到的云边界的差异。结果表明,通常MPL探测的云底高度高于MMCR;其中在高层云个例中,二者相差最大,其它个例中,差别较小;云粒子对毫米波电磁波和激光光束的散射机制的不同以及两个设备判定云边界方法的不同是差异产生的主要原因。对于云顶的小粒子和云内的小冰晶,MPL的探测能力强于MMCR;但对于发展深、厚的云层,MPL会因衰减的影响探测不到真实的云顶,而MMCR可以探测到完整的云层。

Comparison analysis of cloud boundary detection by means of millimeter wavelength cloud radar and lidar

To detect cloud boundaries accurately , millimeter wavelength cloud radar ( MMCR ) and micropulse lidar (MPL) were combined and used to detect stratocumulus , altostratus, altocumulus and cirrocumulus.Differences of cloud boundaries detected by two radars were analyzed comparatively .The results show that the cloud base height detected by MPL is usually higher than MMCR .The difference is large for altostratus but is small for other cases .The differences are mainly due to the different scattering mechanisms of cloud particle for light beam and microwave electromagnetic wave , and the different identification methods of cloud boundaries by MPL and MMCR .For small particles at the top of cloud and small ice crystals in the cloud, the detection ability of MPL is more powerful than MMCR .But for deep cloud, MPL can't detect the real top of cloud because of attenuation effect .Under the same situation , MMCR can completely penetrate the clouds .