利用CINRAD/CD雷达产品和FY-4A卫星数据及云特征量产品,结合地面、Micaps环流场和探空等资料,针对2018年6月17日青藏高原那曲中东部一次强天气过程综合分析了冰雹云的演变及结构特征,探讨了新型探测资料在冰雹监测预警中的应用。结果表...利用CINRAD/CD雷达产品和FY-4A卫星数据及云特征量产品,结合地面、Micaps环流场和探空等资料,针对2018年6月17日青藏高原那曲中东部一次强天气过程综合分析了冰雹云的演变及结构特征,探讨了新型探测资料在冰雹监测预警中的应用。结果表明:(1)受500 h Pa高原槽和地面切变线共同影响,午后地面增温使得那曲中东部对流冷云单体发展,在其东移过程中不断与新生对流云合并加强,导致那曲市区和索县出现降雹。(2)冰雹出现区域与云顶亮温<-50℃区域及冰雹云移动路径有很好的对应关系,大冰雹落区在TBB值低于-50℃的负中心内。(3)高原冰雹云的雷达组合反射率、垂直液水含量、垂直液水含量密度和回波顶高在降雹前均出现陡增,降雹结束前维持较高水平,有利于冰雹粒子的发展;高原地区垂直液态水含量密度较低,强对流发展也相对较弱,难以产生强冰雹天气。(4)高原冰雹云具有粒子有效半径和云光学厚度较大的特点,符合高原农牧区冰雹云FY-4A卫星云特征参量的监测预警指标。(5)高原冰雹云较低的晶化温度使云体具有深厚的过冷水层,为冰雹增大提供了充分的环境。展开更多
A case of hailstorm process occurring on 24 June 2006 in northwestern China was studied using satellite retrieval methodology. The particle effective radius (re) in the cloud tops was calculated by the reflectance in ...A case of hailstorm process occurring on 24 June 2006 in northwestern China was studied using satellite retrieval methodology. The particle effective radius (re) in the cloud tops was calculated by the reflectance in the 3.7 μm channel, and cloud-top microphysical properties were vividly represented using the RGB visual multispectral classification scheme. The microphysical zones of clouds and the processes of hail formation and develop-ment are inferred using the relations of cloud-top temperature (T) versus re for the tops of convective clouds. The results show that particle effective radius was smaller near the cloud base of hailstorm. There was a deep zone of diffusional droplet growth at the low level where the particles grew slowly with height, and there existed an evident area of small ice particles in the cloud top, suggesting the existence of a strong updraft in the clouds. The low glaciated temperature indicated a great depth from the cloud base to the glaciation height, which provided a deep layer of supercooled water for hail growth.展开更多
文摘利用CINRAD/CD雷达产品和FY-4A卫星数据及云特征量产品,结合地面、Micaps环流场和探空等资料,针对2018年6月17日青藏高原那曲中东部一次强天气过程综合分析了冰雹云的演变及结构特征,探讨了新型探测资料在冰雹监测预警中的应用。结果表明:(1)受500 h Pa高原槽和地面切变线共同影响,午后地面增温使得那曲中东部对流冷云单体发展,在其东移过程中不断与新生对流云合并加强,导致那曲市区和索县出现降雹。(2)冰雹出现区域与云顶亮温<-50℃区域及冰雹云移动路径有很好的对应关系,大冰雹落区在TBB值低于-50℃的负中心内。(3)高原冰雹云的雷达组合反射率、垂直液水含量、垂直液水含量密度和回波顶高在降雹前均出现陡增,降雹结束前维持较高水平,有利于冰雹粒子的发展;高原地区垂直液态水含量密度较低,强对流发展也相对较弱,难以产生强冰雹天气。(4)高原冰雹云具有粒子有效半径和云光学厚度较大的特点,符合高原农牧区冰雹云FY-4A卫星云特征参量的监测预警指标。(5)高原冰雹云较低的晶化温度使云体具有深厚的过冷水层,为冰雹增大提供了充分的环境。
基金supported jointly by Chinese Ministry of Science and Technology (Grant 2005DIB3J099)Science Foundation of Shaanxi Province (Grant 2007D11)
文摘A case of hailstorm process occurring on 24 June 2006 in northwestern China was studied using satellite retrieval methodology. The particle effective radius (re) in the cloud tops was calculated by the reflectance in the 3.7 μm channel, and cloud-top microphysical properties were vividly represented using the RGB visual multispectral classification scheme. The microphysical zones of clouds and the processes of hail formation and develop-ment are inferred using the relations of cloud-top temperature (T) versus re for the tops of convective clouds. The results show that particle effective radius was smaller near the cloud base of hailstorm. There was a deep zone of diffusional droplet growth at the low level where the particles grew slowly with height, and there existed an evident area of small ice particles in the cloud top, suggesting the existence of a strong updraft in the clouds. The low glaciated temperature indicated a great depth from the cloud base to the glaciation height, which provided a deep layer of supercooled water for hail growth.
