南京一次雷雨的闪电特征与多尺度资料分析

为探究闪电与其他气象要素之间的关系及可预报性,本文利用探空资料、多普勒天气雷达资料、闪电定位仪资料、卫星云图资料和地面自动气象站资料,对2009年7月7日南京雷雨天气进行多尺度分析.结果表明:暴雨过程中负地闪始终占较大比例,正地闪的数目在雷暴消散阶段稍有增长；地闪频数与地面风速时序变化呈现很好的一致性；雷暴来临前风矢位温特征表明对流云发展高度较高,对流层顶的薄层超低温为强对流发生提供了热力不稳定的先兆信息,整层大气深厚的顺时针垂直切变及中低层偏南风为强对流天气提供了有利的动力和水汽条件,为雷暴潜势预报提供了依据；地闪分布与雷达回波顶高、强的风切变区域以及暴雨落区有明显对应关系；负地闪密集区位于雷达强回波核前方强度为40 ～45dBz区域处,对于回波的未来移向有指示作用.

The case study of thunderstorm with lightning characteristic and multi-scale data

The analysis of convective weather on 7 July, 2009 was made with the data of lightning detection, radiosonde, Doppler radar, FY series satellites and multiple surface observation whose aims are to provide theoretical basis for thunderstorm potential forecast, to deeply understand the dynamic, thermal and humidity structure of atmospheric energy, and to explore the relationships between lightning and other meteorological elements. The results show that negative flash ratio of thunderstorm is higher. But for positive flash, its strength reinforcement and scaling-up occurred after convective system reached the mature stage. Based on the energy structural forecasting method, the plot of wind and potential temperature show important signs before the occurrence of convection. Coherence existed between the number of Cloud-to-Ground (CG) flash and the speed of surface wind. Correlation between distribution of CG flashes and occurrence of high echo top, strong wind shear as well as heavy rain has been confirmed. The negative CG flashes mainly occur in the front of the region with echo intensity between 40 and 45 dBz, which has a good instructive sense to forecast the future trend of intense echo zone.