Stable isotope fractionation during ultraviolet photolysis of N2O
Article first published online: 7 DEC 2012
Copyright 1998 by the American Geophysical Union.
Geophysical Research Letters
Volume 25, Issue 24, pages 4489–4492, 15 December 1998
How to Cite
- Issue published online: 7 DEC 2012
- Article first published online: 7 DEC 2012
- Manuscript Accepted: 23 OCT 1998
- Manuscript Received: 25 AUG 1998
The biogeochemical cycling of nitrous oxide plays an important role in greenhouse forcing and ozone regulation. Laboratory studies of N2O:N2 mixtures irradiated between 193–207 nm reveal a significant enrichment of the residual heavy nitrous oxide isotopomers. The isotopic signatures resulting from photolysis are well modeled by an irreversible Rayleigh distillation process, with large enrichment factors of ε15,18(193 nm) = −18.4,-14.5 per mil and ε15,18(207 nm) = −48.7,-46.0 per mil. These results, when combined with diffusive mixing processes, have the potential to explain the stratospheric enrichments previously observed.