摘要
2005年8月5-6日滇中地区发生了一次强对流天气。本文应用滇中地区闪电定位仪和自动站降水资料对此次过程进行了分析,结果显示：此次过程中总闪电频数在时间变化上与降水变化不一致,且在每次降水峰值出现前一小时,闪电活动均有增加的现象。通过对NCEP/NCAR 1°×1°再分析资料的分析发现,闪电在中层相对湿度为45-85%之间活动频繁。当中层的相对湿度超过85%时,会使闪电活动受到抑制,因此降水与闪电在时间的变化上不一致。计算对流抑制能量的结果表明,其绝对值在不高于60 J.kg^-1时有利于滇中不稳定能量在低层的积聚,后期易发生闪电,这对闪电的落区预报有意义。
The evolution of cloud - to - ground lightning in a heavy rainfall was analyzed by using the data from lightning detection system, automatics weather observation system. The result shows that the variety of frequency of lightning is not consistent with that of rainfall, and the increment of lightning occurs an hour ahead when the maximum of rainfall happens. When the relative humility is 45 - 85% in the middle aerosphere, the lightning activity will enhance. While it exceed 85% , the lightning activity will be restrained. By analysis of the relativity between the convective restrain energy and the lightning, it shows that it is propitious to amass the instable energy in the lower aerosphere in Yunnan province when the absolute value of convective restrain energy is less than 60J · kg^- 1 , and the lightning will appear subsequently.
出处
《高原山地气象研究》
2008年第2期29-32,共4页
Plateau and Mountain Meteorology Research
基金
云南省科技攻关及高新技术计划(2006SG25)
关键词
强降水
闪电
对流抑制能量
相对湿度
rainfall lightning activity convective restrain energy relative humidity
