[Objective]The aim was to analyze the mesoscale and small scale system that influenced the strong rainfall in Hunan from June 18 to 20 in 2010. [Method] By dint of regular observation material and rainfall in regional...[Objective]The aim was to analyze the mesoscale and small scale system that influenced the strong rainfall in Hunan from June 18 to 20 in 2010. [Method] By dint of regular observation material and rainfall in regional automatic station, TBB of FY-2C geostationary meteorological satellite, characteristics and causes of one heavy rainfall event in Hunan Province on 18-20 June 2010 were studied. [Result] The rainstorm happened under the southwest warm and wet torrent at the edge of subtropical high when the ground cold air intruded, which triggered the release of unstable energy. The water vapor from Bay of Bengal and South China Sea sent abundant water vapor to south China. The water vapor strengthened, which synchronized with the rainstorm. The ground mesoscale convergence line and the mesoscale low pressure intensified the rainstorm. Changes of pressure field reflected the changes of rainfall and indicated the location and movement of heavy rainfall. [Conclusion] The study provided theoretical basis to understand the rainstorm formation mechanism and improve disaster prevention capacity.展开更多
利用新一代多普勒天气雷达资料及国家、区域自动站和常规高空地面资料,分析了2008-2013年河南省9次区域暴雨回波系统的形态、结构特征、移动特点和降水强度等,分析了区域暴雨过程中中γ尺度对流系统的降水特征。结果表明：1）河南区域...利用新一代多普勒天气雷达资料及国家、区域自动站和常规高空地面资料,分析了2008-2013年河南省9次区域暴雨回波系统的形态、结构特征、移动特点和降水强度等,分析了区域暴雨过程中中γ尺度对流系统的降水特征。结果表明：1）河南区域暴雨落区主要位于高空槽前和副高西北侧、中低层切变线之间、低涡东南侧、低空急流左前侧,以及地面倒槽或气旋顶部偏北到偏东气流中。2）从新一代雷达监测产品来看,河南省区域暴雨主要有积云降水、积层混合降水和层状云降水三种回波类型,其中混合降水包括以积云为主的混合降水和以层云为主的混合降水,是河南省区域暴雨的主要回波类型。3）降水强度与回波类型、结构特征、移动特点等均有关系,特别是≥50 mm/h的短时强降水与γ中尺度对流系统密切相关,强降水超级单体可造成局地50 mm/h以上的强降水,并多伴有雷暴大风、龙卷等剧烈对流天气。一般情况下,积云降水强度最大,混合降水次之,层云降水强度最小。综合分析来看,雨强与回波强度比与回波性质有更好的相关性。≥50 mm/h的强降水多由强降水超级单体和因辐合、气旋、后向传播等使回波加强、合并、发展旺盛的准静止状态的50~60 d Bz的强积云降水回波产生;≥20 mm/h强降水多由积层混合降水中≥45 d Bz的积云回波产生。10 mm/h以上的降水落区和≥40 d Bz的较强回波有很好的对应关系;〈40 d Bz的层云回波降水强度通常在10 mm/h以下。展开更多
基金Supported by National Meteorological Bureau Program in 2011 (GY-HY201106003)
文摘[Objective]The aim was to analyze the mesoscale and small scale system that influenced the strong rainfall in Hunan from June 18 to 20 in 2010. [Method] By dint of regular observation material and rainfall in regional automatic station, TBB of FY-2C geostationary meteorological satellite, characteristics and causes of one heavy rainfall event in Hunan Province on 18-20 June 2010 were studied. [Result] The rainstorm happened under the southwest warm and wet torrent at the edge of subtropical high when the ground cold air intruded, which triggered the release of unstable energy. The water vapor from Bay of Bengal and South China Sea sent abundant water vapor to south China. The water vapor strengthened, which synchronized with the rainstorm. The ground mesoscale convergence line and the mesoscale low pressure intensified the rainstorm. Changes of pressure field reflected the changes of rainfall and indicated the location and movement of heavy rainfall. [Conclusion] The study provided theoretical basis to understand the rainstorm formation mechanism and improve disaster prevention capacity.
文摘利用新一代多普勒天气雷达资料及国家、区域自动站和常规高空地面资料,分析了2008-2013年河南省9次区域暴雨回波系统的形态、结构特征、移动特点和降水强度等,分析了区域暴雨过程中中γ尺度对流系统的降水特征。结果表明：1）河南区域暴雨落区主要位于高空槽前和副高西北侧、中低层切变线之间、低涡东南侧、低空急流左前侧,以及地面倒槽或气旋顶部偏北到偏东气流中。2）从新一代雷达监测产品来看,河南省区域暴雨主要有积云降水、积层混合降水和层状云降水三种回波类型,其中混合降水包括以积云为主的混合降水和以层云为主的混合降水,是河南省区域暴雨的主要回波类型。3）降水强度与回波类型、结构特征、移动特点等均有关系,特别是≥50 mm/h的短时强降水与γ中尺度对流系统密切相关,强降水超级单体可造成局地50 mm/h以上的强降水,并多伴有雷暴大风、龙卷等剧烈对流天气。一般情况下,积云降水强度最大,混合降水次之,层云降水强度最小。综合分析来看,雨强与回波强度比与回波性质有更好的相关性。≥50 mm/h的强降水多由强降水超级单体和因辐合、气旋、后向传播等使回波加强、合并、发展旺盛的准静止状态的50~60 d Bz的强积云降水回波产生;≥20 mm/h强降水多由积层混合降水中≥45 d Bz的积云回波产生。10 mm/h以上的降水落区和≥40 d Bz的较强回波有很好的对应关系;〈40 d Bz的层云回波降水强度通常在10 mm/h以下。
