利用3 mm波云雷达以及加密探空等观测资料，分析了2008年11月6-8日安徽寿县先后两次冷锋过境产生的锋面混合相云垂直结构及过冷水分布。结果表明，本次锋面混合相云存在“播撒-供给”的垂直结构；锋面混合相云存在回波强度、多普勒速度和速度谱宽三条亮带，并且速度谱宽亮带高度低于多普勒速度亮带高度，多普勒速度亮带高度低于回波亮带高度；在水平结构不均匀的云场中，下落粒子群存在“筛选作用”；本次过程锋面混合相云存在一定过冷水，云层中过冷水的垂直分布是不连续的，其分布的温度范围比较广。
The vertical structure of the cloud directly affects the micro-physical processes, thus affecting the occurrence and intensity of precipitation.Cloud Radar can be used to directly detect the vertical structure of the cloud, which is of great significance to understand the physical process of cloud precipitation.The theory of the artificial rainfall and operating conditions identification technology research is very focus on the distribution of mixed phase clouds and supercooled water in the front.Many scholars mainly analyze the vertical structure of the cloud and the distribution of supercooled water from the aspects of telemetry, in-cloud observation and numerical model.With 3 mm wave cloud radar data and sounding data, the vertical structure and distribution of supercooled water of two frontal mixed cloud processes from 6 to 8 November 2008 in Shouxian, Anhui were analyzed in detail.The vertical strcture analysis included the cloud structure analysis in cold region, the bright band analysis in melting layer and the cloud structure analysis in warm region.The results show that Shouxian in Anhui Province had been affected by the impact of the west weak cold front and the east cold front on 6~8 November 2008.It produced thick mixed phase cloud in 11:00-13:00 (BJT, the same as after) on 6 and in 01:00-04:00 on 7, but the precipitation of the two periods was relatively small.Frontal mixed cloud existed "Sow-Supply" vertical structure in this process.The top temperature of the frontal mixed phase cloud was low, the ice crystals produced in the cloud, then dropped to provide the "Sow effect".There was some supercooled water in the cloud, which provided "Supply effect" to the dropping ice and snow crystals.Frontal mixed cloud has echo intensity, Doppler velocity and velocity specturem width three bright bands.Because of the ice and snow crystals in the melted surface had the reflection characteristics of water droplets, and different sizes ice and snow crystals with different melting time and different drop final velocity, the velocity specturem bright band with a height less than Doppler velocity bright band, and Doppler velocity bright band with a height less than echo intensity bright band.In a cloud field with uneven horizontal structure, falling particle swarm has obvious "filtering effect", which is not conducive to the growth of raindrops.Therefore, the radar echo intensity and the Doppler velocity region were not consistent, the Doppler velocity region appeared in the front of the strong echo area in the middle and upper part of the warm region.There were certain supercooled water in frontal mixed cloud, and the vertical distribution of supercooled water was not continuous, and the distribution of the temperature range was relatively wide.Because of 3 mm cloud radar observation data is less in China, this paper only analyzed a case of frontal mixed phase cloud vertical structure, and the results still need more data for further validation.In addition, the temperature range of the supercooled water distribution obtained by the inversion algorithm of Shupe and the temperature range of the observation of the supercooled water in China has a certain difference, but also need to be furher confirmed.
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