Global distributions and occurrence rates of transient luminous events
Global distributions and occurrence rates of transient luminous events
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DOI：
10.1029/2008ja013101
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发表时间：
2008-08-15
影响因子：
2.8
通讯作者：
Lee, Lou-Chuang
中科院分区：
文献类型：
--
作者：
Chen, Alfred B.;Kuo, Cheng-Ling;Lee, Lou-Chuang
我们基于FORMOSAT-2卫星上的Sprites和高层大气闪电成像仪（ISUAL）实验报告了全球瞬时发光事件（TLE）的分布和速率。ISUAL观测在北方夏季覆盖南纬45度至北纬25度，在北方冬季覆盖南纬25度至北纬45度。从2004年7月到2007年6月，ISUAL记录了5，434个精灵，633个精灵，657个光环和13个巨大的喷气机。令人惊讶的是，精灵是TLE的主要类型，而精灵/光环是第二种。当海表温度超过26 ℃时，ELVE发生率会发生跳跃，体现了海洋-大气-电离层的耦合。在ISUAL的调查中，精灵集中在加勒比海、南中国海、东印度洋、中太平洋、西大西洋和西南太平洋;而精灵则集中在非洲中部、日本海和西大西洋。ISUAL实验观测到精灵、精灵、光环和巨大喷流的全球速率分别为每分钟3.23、0.50、0.39和0.01次。考虑到仪器检测灵敏度和有限的调查区域，精灵和精灵的校正全球发生率可能分别高出两个因子和一个数量级。ISUAL的观测还表明，高峰电流闪电（> 80千安）的相对频率在海洋上比在陆地上高10倍。根据修正后的ISUAL elve全球出现率，计算出elve热区以上低电离层总电子含量增加了5%以上。
We report the global transient luminous event (TLE) distributions and rates based on the Imager of Sprites and Upper Atmospheric Lightning (ISUAL) experiment onboard the FORMOSAT-2 satellite. ISUAL observations cover 45 degrees S to 25 degrees N latitude during the northern summer and 25 degrees S to 45 degrees N latitude during the northern winter. From July 2004 to June 2007, ISUAL recorded 5,434 elves, 633 sprites, 657 halos, and 13 gigantic jets. Surprisingly, elve is the dominant type of TLEs, while sprites/halos are a distant second. Elve occurrence rate jumps as the sea surface temperature exceeds 26 degrees Celsius, manifesting an ocean-atmosphere-ionosphere coupling. In the ISUAL survey, elves concentrate over the Caribbean Sea, South China Sea, east Indian Ocean, central Pacific Ocean, west Atlantic Ocean, and southwest Pacific Ocean; while sprites congregate over central Africa, Japan Sea, and west Atlantic Ocean. The ISUAL experiment observed global rates of 3.23, 0.50, 0.39, and 0.01 events per minute for elves, sprites, halos, and gigantic jets, respectively. Taking the instrumental detection sensitivity and the restricted survey area into account, the corrected global occurrence rates for sprites and elves likely are a factor of two and an order of magnitude higher, respectively. ISUAL observations also indicate that the relative frequency of high peak current lightning (> 80 kA) is 10 times higher over the oceans than over the land. On the basis of the corrected ISUAL elve global occurrence rate, the total electron content at the lower ionosphere above elve hot zones was computed to be elevated by more than 5%.