Abstract
The sources and steady-state concentration of singlet oxygen in the atmosphere are assessed in view of potential effects on the biosphere. Collision-induced absorption of sunlight by molecular oxygen in 1 atm of air produces O2 (a1 delta g) at a rate P = 1.6 x 10(9) cm-3 s-1 in bright sunlight. Less than 10% are added to this purely natural source by the photolysis of ozone, and by anthropogenic sensitizers (SO2, NO2, volatile aromatics). Collisional quenching of O2 (a1 delta g) by ground state oxygen establishes a steady-state concentration of ca. 1.7 x 10(8) cm-3. Reactions of singlet oxygen with other atmospheric pollutants are entirely negligible when compared with the concurrent reactions of ambient OH and O3. Potential effects of atmospheric singlet oxygen on the biosphere are limited by the deposition rate F less than or equal to 0.051 P, which depends on the production rate P of O2 (a1 delta g) in the air layer immediately above the flat surface.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.