摘要
利用VHF辐射源三维定位系统及快、慢天线资料,对青海大通地区5次雷暴过程中云闪、负地闪、正地闪的起始高度、持续时间、辐射源数目及正、负地闪云内放电过程的持续时间和回击次数进行了统计分析。研究表明,该地区闪电持续时间较短,平均<0.5s;正、负地闪首次回击发生前均有较长时间的云内放电过程,正地闪的云内放电过程持续时间略长于负地闪;负地闪的回击次数较少,平均为2.5次,其中40%的负地闪只有1次回击,而正地闪回击次数均为1次;云闪的起始高度最高,负地闪的起始高度低于云闪,正地闪的起始高度最低;云闪产生的辐射源数目最多,负地闪少于云闪,正地闪产生的辐射源数目最少。
Some characteristics of lightning flashes in northeastern Qinghai-Xizang Plateau were analyzed u- sing the three-dimensional lightning locating system, fast and slow antennas. It is found that the duration of flashes is not long, averagely less than 0.5 s. Both the positive and negative cloud-to-ground flashes have long duration of intracloud discharge process before the first return stroke, and it is slightly longer for positive cloud-to-ground flashes. The average number of strokes per negative cloud-to-ground flash is 2.5, and 40 % of the negative cloud-to-ground flashes are single-stroke flashes, while all the positive cloud- to-ground flashes are single-stroke flashes. The average starting height of intracloud flashes is higher than the negative cloud-to-ground flashes, and that of the positive cloud-to-ground flashes is lower than the neg- ative cloud-to-ground flashes. Meanwhile, the average number of radiation sources generated by intracloud flashes is the largest, followed by negative cloud-to-ground flashes, and that of positive cloud-to-ground flashes is the smallest.
出处
《高原气象》
CSCD
北大核心
2013年第3期673-681,共9页
Plateau Meteorology
基金
国家自然科学基金项目(41075002
40775004)
国家自然科学基金重点项目(41030960)共同资助
公益性行业科研专项(GYHY201006005-03)
关键词
闪电
起始高度
辐射源
Lightning flash
Starting height
Radiation source
