祁连山一次地形云降水微物理特征飞机观测  

Aircraft Measurement of Microphysical Characteristics of a Topographic Cloud Precipitation in Qilian Mountains

作　　者：程鹏 罗汉 常祎 甘泽文 张丰伟 刘维成[5] 陈祺[2] 冒立鑫 Cheng Peng;Luo Han;Chang Yi;Gan Zewen;Zhang Fengwei;Liu Weicheng;Chen Qi;Mao Lixin(Lanzhou Meterological Bureau of Gansu Province,Lanzhou 730020;Gansu Weather Modification Office,Lanzhou 730020;Key Laboratory for Cloud Physics of China Meteorological Administration,Beijing 100081;Sichuan Weather Modification Office,Chengdu 610072;Lanzhou Central Meterological Observatory,Lanzhou 730020;Minle Meterological Bureau of Gansu Province,Zhangye 734500)

机构地区：[1]甘肃省兰州市气象局,兰州730020 [2]甘肃省人工影响天气办公室,兰州730020 [3]中国气象局云雾物理环境重点开放实验室,北京100081 [4]四川省人工影响天气办公室,成都610072 [5]兰州中心气象台,兰州730020 [6]甘肃省张掖市民乐县气象局,张掖734500

出　　处：《应用气象学报》2021年第6期691-705,共15页Journal of Applied Meteorological Science

基　　金：第二次青藏高原综合科学考察(2019QZKK0104);甘肃省自然科学基金(20JR10RA455);甘肃省气象局科研重点项目(Zd2021-03)。

摘　　要：祁连山是我国西北地区重要的生态屏障,地形云是祁连山主要降水云系,加强对祁连山云微物理过程的认识,对科学有效开展人工增雨作业、改善生态环境具有重要意义。利用2020年8月29日祁连山一次地形云降水过程的飞机观测数据,研究祁连山地区夏季云降水过程的微物理特征。此次降水过程云系呈明显的分层结构,云底高度为4000 m,整层含水量较丰富,云水大值区出现在4500~5300 m高度,与云滴高浓度区对应,云水含量主要由粒子直径为15~20μm的云滴粒子贡献。小云粒子和大云粒子平均浓度分别为7.54 cm^(-3)和0.86 cm^(-3),有效直径平均值分别为11.02μm和198.11μm,呈现出浓度小、直径大的特征。云系翻越祁连山过程中南北坡云微物理特征有明显变化,北坡(背风坡)粒子浓度、直径和液态水含量明显大于南坡(迎风坡)。祁连山地区不同高度小云粒子谱呈单峰型分布,Gamma分布可较好拟合直径小于50μm的云滴谱,直径大于50μm的云粒子谱更符合幂指数分布。凝华和聚并是冰相层冰雪晶的增长机制,混合层冰晶增长以贝吉龙过程为主,并伴有凇附和聚并生长。Qilian Mountains are an important ecological barrier in Northwest China.The precipitation in Qilian Mountains is mainly caused by topographical cloud system.Aircraft detection in Qilian Mountains is of great significance for deepening the understanding of cloud microphysical processes,and for scientifically and effectively carrying out artificial precipitation operations to improve the ecological environment.Using the airborne observations of a topographic cloud precipitation process in Qilian Mountains on 29 August 2020,the microphysical characteristics of the summer cloud precipitation process in Qilian Mountains are studied.The cloud system presents an obvious layered structure.The height of the cloud base is 4000 m,and the water content of the whole layer is relatively rich.The liquid water content(L)is between 0.65 and 1.1 g·m^(-3),and the cloud water large value area appears at 4500-5300 m altitude,which has a high concentration of cloud droplets.The water content of cloud water is mainly contributed by cloud droplets between 15 and 20μm.The average concentrations of small cloud particles and large cloud particles are 7.54 cm^(-3)and 0.86 cm^(-3).The average effective diameters of small cloud particles and large cloud particles are 11.02μm and 198.11μm.The cloud particles in Qilian Mountains have the characteristics of small concentration and large diameter.There are obvious differences in cloud microphysical characteristics between the north and south slopes of Qilian Mountains.Affected by the topography,the concentration and diameter of cloud droplets on the northern slope are larger than those on the southern slope,and L on the northern slope are significantly larger than those on the southern slope too.The spectra of cloud droplets at different heights in Qilian Mountains are respectively unimodal distribution.The spectrum of cloud droplets with a diameter less than 50μm can be fitted by Gamma distribution,while the spectrum of cloud droplets with a diameter greater than 50μm shows a power exponen

关 键 词：祁连山 云微物理特征 液态水含量 云粒子谱 飞机观测 

分 类 号：P412.24[天文地球—大气科学及气象学] P426