摘要
通过利用大气平均电场仪和快、慢电场变化仪等仪器设备对青藏高原腹地那曲地区的雷电物理特征进行了分析。发现高原雷暴天气过程中发生的闪电与低海拔地区的相比存在许多的特殊性。这些特殊性主要表现在:闪电在短时间内可以引起较大的电场变化,接近±50kV/m;在一次雷暴天 气过程中的短时强降水可以改变大气平均电场的极性,存在着多个FEAWP过程。较多的地闪只有一次回击,占总地闪数的36.3%,地闪回击数最多的可达到17次,平均为4.11次。地闪中正地闪比率较高可以达到32％。对于负地闪继后回击的电场幅度与首次回击的比与其他地区相比非常高,其平均值为1.42,其中最大值为11.64,最小值为0.17。占总数62％的地闪的连续电流发生在首次回击之后,其持续时间绝大多数在60-160ms之间。
The physical characteristics of lightning flashes in thunderstorms occurred in center of Qinghai-Tibetan Plateau have been analyzed by using the instruments such as the electric field mill, fast and slow antennas. It has been found that the lightning flashes in the plateau present some special characteristics compared with ones in lower altitude regions. These major characteristics are: the electric field can be changed in a large extent, which is close to ±50kV/m, by lightning flashes in a very short time. Much heavy precipitation in short time can change the polarity of electric field, and there are several FEAWPs in thunderstorm. About 36.3% of CG lightning flashes just have one return stroke. The largest number of return strokes in a CG lightning flash is 17, and the average value is 4.11. 32% of CG lightning flashes are positive ones. Ratio of the peak electric field amplitudes of subsequent return strokes to ones of first return strokes for negative CG lightning flashes is very high, its average value is 1.42, the highest one is 11.64, and the lowest one is 0.17. 62% of continuing currents occur after the first return stroke, and their durations are between 60 and 160ms.
出处
《中国电机工程学报》
EI
CSCD
北大核心
2004年第9期198-203,共6页
Proceedings of the CSEE
基金
国家自然科学基金"十五"重点项目(40135010)
中国科学院寒区早区环境与工程研究所所创新领域项目(2004108)~~
关键词
高电压技才
雷电物理特征
闪电
电场
青藏高原腹地
High voltage engineering
Center of Qinghai-Tibetan plateau
Lightning physics
CG lightning flash
IC lightning flash
