嵐の雲の中で雷によって生成される極度の酸化物質量
W H Brune1, P J McFarland2, E Bruning3
1Department of Meteorology and Atmospheric Science, Pennsylvania State University, University Park, PA, USA. whb2@psu.edu.
Science (New York, N.Y.)
|April 30, 2021
まとめ
ライトニングは,重要な大気酸化物質であるヒドロキシル (OH) とヒドロペロキシル (HO2) を直接生成します. この発見は 稲妻を明らかにしています
科学分野:
- 大気 化学 と 物理
- 嵐の電化とダイナミクス
背景:
- 大気化学における雷の役割は,主にオゾン (O3) とヒドロキシル基 (OH) の形成に影響を与える酸化窒素 (NO) の生成に関連しています.
- OHやヒドロペロキシル基 (HO2) のような主要な酸化物質の生成に対する雷の直接的な貢献は,数値的に十分に示されていない.
研究 の 目的:
- ハイドロキシル (OH) とヒドロペロキシル (HO2) の直接生成を 雷で調べる
- 深層コンベクションイベント中に雷によって生成されたOHとHO2の大きさを定量化するために.
主な方法:
- 2012年の深層コンベクションと化学の研究からの空中測定の分析.
- 酸化物質濃度 (OH,HO2) と観測された雷の活動との相関関係,目に見える閃光と目に見えない放電を含む.
主要な成果:
- 雷によるOHとHO2の非常に高い濃度の直接生成が観察されました.
- 高いOHとHO2レベルは,目に見える稲妻と,目に見えない電流と直接関連しています.
- 観測されたOHとHO2の濃度は,以前記録された大気中の濃度よりも大きかった.
結論:
- 稲妻は大気中の酸化物質OHとHO2の重要な直接源です.
- 全球的に見ると,雷によるOHは大気中のOH酸化の2~16%を占め,大気中の自己浄化能力に影響を与えます.
- この発見は,世界の大気化学と酸化物質の予算における雷の役割を再評価することを必要としています.
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