闪电引起的天电和红闪现象的模拟研究

用二维时变的电磁场模型，研究了闪电放电产生的天电和红闪现象.模拟结果表明：闪电放电产生的电场包括辐射场和准静电场.辐射场在地面-电离层波导中传播形成大气中的天电.由准静电场引起的N₂分子第一个正波段的光辐射形成红闪现象.用模拟的方法表明，在红闪的空间结构发生变化的过程中，有明显“V”形结构; 在红闪的整体机构中，中心部分是一个光强度相对较强的核，周围包着光强度相对较弱的晕.关键词：红闪天电电磁场模型

The simulation study of spherics and red sprite phenomenon produced by lightning

By using a two-dimensional, time-dependent electromagnetic field model (EM model), the spherics and red sprite phenomenon is studied. The simulation results show that the total electric fields produced by lightning include radiation field and quasi-electrostatic field (QEF). The spherics result from the radiation field, which propagates within the earth-ionosphere waveguide. The optical emissions of the first positive band of N₂ caused by the QEF form the red sprite phenomenon. By means of simulation we have found the red sprite apparently appearing in “V” shape during its evolution and a bright nucleus existing within the structure of the red sprite, while the brightness of the exterior of the red sprite, which is referred to as sprite halo, being relatively weaker.