在暴风雨中产生的极端氧化剂量
W H Brune1, P J McFarland2, E Bruning3
1Department of Meteorology and Atmospheric Science, Pennsylvania State University, University Park, PA, USA. whb2@psu.edu.
概括
雷电直接产生基 (OH) 和基 (HO2) 激素, 它们是重要的大气氧化剂. 这一发现揭示了闪电
科学领域:
- 大气化学与物理
- 雷暴电气化和动力学
背景情况:
- 雷电在大气化学中的作用主要与氧化 (NO) 生产有关,影响臭氧 (O3) 和基 (OH) 的形成.
- 雷电对OH和基 (HO2) 等关键氧化剂的产生直接贡献的量度很差.
研究的目的:
- 通过闪电直接产生基 (OH) 和基 (HO2).
- 在深度对流事件中量化闪电产生的OH和HO2.
主要方法:
- 来自2012年深度对流和化学研究的空气测量分析.
- 氧化剂度 (OH,HO2) 与观察到的闪电活动的相关性,包括可见的闪光和不可见的放电.
主要成果:
- 通过闪电直接产生异常高度的OH和HO2基.
- 高水平的OH和HO2直接与可见的闪电和未见的电流有关.
- 观察到的OH和HO2增强量比以前记录的大气度大.
结论:
- 闪电是大气氧化剂OH和HO2的重要直接来源.
- 在全球范围内,闪电产生的OH可能占大气中OH氧化总量的2-16%,影响大气的自我清洁能力.
- 这一发现需要重新评估闪电在全球大气化学和氧化剂预算中的作用.
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