Decomposition of long-lived greenhouse gases by atmospheric streamers

Sulfur hexafluoride (SF₆) and carbon tetrafluoride (CF₄) are inert gases in the atmosphere that can absorb infrared radiation and affect the climate. They have lifetimes up to 1278 years for SF₆ and 50000 years for CF₄. The International Panel on Climate Change lists the two as part of the most influential long-lived, well-mixed greenhouse gases, with SF₆ having the highest identified global warming potential. Both gases have anthropogenic major sources. SF₆ is used as an insulating gas in the electrical power industry, and CF₄ is a by-product of aluminum manufacturing. In this study, we question whether atmospheric electricity significantly influences the atmospheric concentrations of these molecules. We aim to investigate SF₆ and CF₄ decomposition within streamers at different altitudes in the atmosphere, and then estimate the global occurrence rate of such streamers and their impact. To accomplish this, we simulate positive streamers in synthetic air that contains a small concentration of the two gases. From our simulations, we identify relations between streamer properties and the amounts of SF₆ and CF₄ destroyed, which can be used to estimate the rates of chemical processes in observed streamer events.