A Born-Oppenheimer photolysis model of N2O fractionation
Article first published online: 28 JUN 2003
Copyright 2003 by the American Geophysical Union.
Geophysical Research Letters
Volume 30, Issue 12, June 2003
How to Cite
2003), A Born-Oppenheimer photolysis model of N2O fractionation, Geophys. Res. Lett., 30, 1656, doi:10.1029/2003GL016932, 12., , , and (
- Issue published online: 28 JUN 2003
- Article first published online: 28 JUN 2003
- Manuscript Accepted: 9 APR 2003
- Manuscript Revised: 21 MAR 2003
- Manuscript Received: 15 JAN 2003
 The isotopically light N2O produced by microbial activity is thought to be balanced by the return of heavy stratospheric nitrous oxide. The Yung and Miller  method that first explained these trends yields photolytic fractionation factors ∼half those observed by experiment or predicted quantum mechanically, however. To address these issues, we present here a Born-Oppenheimer photolysis model that uses only commonly available spectroscopic data. The predicted fractionations quantitatively reproduce laboratory data, and have been incorporated into zonally averaged atmospheric simulations. Like McLinden et al. , who employ a three-dimensional chemical transport model with cross sections scaled to match laboratory data, we find excellent agreement between predictions and stratospheric measurements; additional processes that contribute to the mass independent anomaly in N2O can only account for a fraction of its global budget.