一次强对流过程中的闪电特征分析  

Analysis on the Lightning Characteristics of a Severe Convection Event

作　　者：黄延刚[1] 顾松山[1] 杨才文[2] 胡胜[2] 何如意[2] 

机构地区：[1]南京信息工程大学遥感学院,江苏南京210044 [2]广州中心气象台,广东广州510080

出　　处：《广东气象》2007年第3期7-10,共4页Guangdong Meteorology

基　　金：广州市科技攻关项目(06A13043333)

摘　　要：利用闪电定位系统和多普勒雷达资料,通过2007年4月24日广东省一次强对流过程,剖析了不同阶段的闪电特征和雷达回波的关系.结果表明,（1）对流云带放电整体上呈带状分布,闪电随云带的移动而移动,强对流单体发生的闪电频数大且密集.（2）强降水过程中闪电活动呈双峰型分布,负闪占绝对优势,正负闪同步增加或减少,正闪电流平均幅值大于负闪,基本上是负闪的2倍.（3）闪电频数、强度和雷达回波强度在时间序列上对应较好;发生发展阶段,闪电出现位置超前雷达回波约10～40 min;在成熟和消散阶段,闪电主要发生在雷达回波＞40 dBz和VIL＞20 kg/m2所对应的区域,并在其周围形成一个小范围的闪电密集区.The lightning location system data and regional Doppler radar mosaic from a severe convection event in Guangdong Province on 24 April 2007 are used to investigate the relationships between hghtning and radar echoes at different stages. Results show that ： （ 1 ） Convective cloud discharge was distributed as banded structure and moved along with cloud band; lightning with high frequency and density occurred in severe convective cells. （2） During this heavy precipitation weather process, the lightning activities show bimodal distribution, most of which are negative lightning. Positive and negative lightning were synchronously increases or decreases. Positive lightning current intensity was twice as high as negative one. （3） Lightning frequency and intensity accorded with radar echoes intensity in time series. At the new born to developing stage, lightning was 10-40 minutes earlier than radar echoes. At the mature and dissipative stage, lighting mainly took place in regions with radar echo a- bove 40 dBz and VIL greater than 20 kg/m^2, hence formed a small and dense cluster around the strong echo areas.

关 键 词：天气学 闪电特征 雷达区域拼图 强对流 

分 类 号：P458[天文地球—大气科学及气象学]