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Title: Extreme oxidant amounts produced by lightning in storm clouds

Lightning increases the atmosphere’s ability to cleanse itself by producing nitric oxide (NO), leading to atmospheric chemistry that forms ozone (O3) and the atmosphere’s primary oxidant, the hydroxyl radical (OH). Our analysis of a 2012 airborne study of deep convection and chemistry demonstrates that lightning also directly generates the oxidants OH and the hydroperoxyl radical (HO2). Extreme amounts of OH and HO2were discovered and linked to visible flashes occurring in front of the aircraft and to subvisible discharges in electrified anvil regions. This enhanced OH and HO2is orders of magnitude greater than any previous atmospheric observation. Lightning-generated OH in all storms happening at the same time globally can be responsible for a highly uncertain, but substantial, 2 to 16% of global atmospheric OH oxidation.

Authors:
 ;  ;  ;  ;  ;  ;  ;  ;  ;  
Award ID(s):
1834711
Publication Date:
NSF-PAR ID:
10228116
Journal Name:
Science
Volume:
372
Issue:
6543
Page Range or eLocation-ID:
p. 711-715
ISSN:
0036-8075
Publisher:
American Association for the Advancement of Science (AAAS)
Sponsoring Org:
National Science Foundation
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