资源环境科技发展态势分析平台

Molecular hydrogen (H₂) is an abundant and reactive constituent of Earth’s atmosphere, with links to climate and air quality. Anthropogenic emissions of H₂ are expected to rise as the use of H₂ as an energy source increases. Documenting past variations in atmospheric H₂ will help to validate current understanding of the global H₂ budget. The modern instrumental record begins in the 1980’s; there is little information about atmospheric H₂ prior to that time. Here, we use firn air measurements from a 2001 South Pole campaign to reconstruct atmospheric H₂ levels over the 20^th century. Inversion of the measurements indicates that H₂ over South Pole has increased from 350‐540 ppb from 1905‐2000. A biogeochemical box model indicates that the atmospheric burden of H₂ increased by 37% over that time. The rise in H₂ is primarily attributed to increasing H₂ emissions from fossil fuel combustion and increasing atmospheric production from methane oxidation.