基于多种观测资料的雷电临近预警方法的研究

Research on Lightning Early Warning Method Based on Multiple Observation Data

摘要: 近年来，由雷电导致的经济损失及社会影响的危害面几乎涉及到各行各业，为此加强雷电预警预报工作及其相关的科学研究，对气象防灾减灾工作有着重要意义。本文利用南京本站、江宁站、昆仑路站、奥体中心站、高淳站、溧水站、浦口站、六合站大气电场仪资料，并结合雷达以及闪电定位资料得出南京市夏季雷暴过程大气电场变化特征。根据首次地闪的发生时刻对南京各站雷暴过程进行细划研究分析，并在此基础上确定了南京本地大气电场仪预警时刻的各项预警参数值以及雷达回波特征。以期尝试探索多源观测资料在改进雷电预警工作中的应用前景，并以此弥补单一大气电场资料在雷电预警工作中的不足。以江宁站为试点建立雷电预警方程得出最佳预警因子参数，结果表明当江宁站电场仪预警阈值持续时间达到16.43分钟左右，该站大气电场增大倍数为晴天大气电场的10.95倍以上，电场阈值分钟变化平均值达到1.7 kv/m，雷达组合反射率因子达到30 dBZ以上，回波顶高达到7 km左右时的预警指标后，该地区将在25分钟左右后发生闪击。通过对江宁站夏季雷暴样本检验的基础上得出此方法准确率达到62%。

Abstract: In recent years, the economic losses and social impacts caused by lightning almost involve all walks of life. Therefore, it is of great significance for meteorological disaster prevention and mitigation to strengthen the early warning and prediction of lightning approach and related scientific research. Based on the data of atmospheric electric field instrument at Nanjing Station, Jiangning Station, Kunlun Road Station, Olympic Sports Center Station, Gaochun Station, Lishui Station, Pukou Station, Liuhe Station, combined with radar and lightning location data, the characteristics of atmospheric electric field variation during summer thunderstorms in Nanjing are obtained. According to the occurrence time of the first ground flash, the thunderstorm process of Nanjing stations was analyzed in detail, and on this basis, the early warning parameters and radar echo characteristics of the local atmospheric electric field instrument in Nanjing were determined, in order to explore the applica-tion prospect of multi-source observation data in improving the lightning early warning work. It can make up for the deficiency of single atmospheric electric field data in lightning warning work. Taking Jiangning Station as a pilot, the lightning approaching warning equation was established to obtain the best warning factor parameters. The results show that when the warning threshold duration of the electric field instrument at Jiangning Station reaches about 16.43 minutes, the increase factor of the electric field instrument at the station is more than 10.95 times that of the electric field instrument on sunny days, and the average change of the electric field threshold in minutes reaches 1.7 kv/m. When the radar combination reflectance factor reaches above 30 dBz and the echo top height reaches about 7 km, the area will blitz about 25 minutes later. Based on the test of summer thunderstorm samples at Jiangning station, the accuracy of this method reaches 62%.