Global Impact of Lightning-Produced Oxidants

Lightning plays a major role in tropospheric oxidation, and its role on modulating tropospheric chemistry was thought to be emissions of nitrogen oxides (NOx). Recent field and laboratory measurements demonstrate that lightning generates extremely large amounts of oxidants, including hydrogen oxides (HOx) and O-3. Here, we implement these lightning-produced oxidants in a global chemical transport model to examine its global impact on tropospheric composition. We find that lightning-produced oxidants can increase global mass weighted OH by 0.3%-10% and affect CO, O-3, and reactive nitrogen substantially, depending on the emission strength of oxidants from lightning. Our work highlights the importance and uncertainties of lightning-produced oxidants, as well as the need for rethinking the role of lightning in tropospheric oxidation chemistry.

Automated summary

Lightning plays a significant role in tropospheric oxidation by generating a large amount of oxidants, including HOx and O-3, which can impact global tropospheric composition, particularly affecting OH, CO, O-3, and reactive nitrogen. The study emphasizes the importance and uncertainties of lightning-produced oxidants, underscoring the need to reconsider the role of lightning in tropospheric oxidation chemistry.