Quantifying the 17O-excess of tropospheric nitrogen oxides to clarify the reaction paths

Abstract

In this study, we used the triple oxygen isotopic compositions of nitric oxide, nitrogen dioxide, gaseous nitrate, and particulate nitrate determined simultaneously as a tracer to clarify the reaction paths from nitric oxide to gaseous/particulate nitrate. While tropospheric ozone displays anomalous enrichment of oxygen-17 in the terminal positions, we can expect the triple oxygen isotopic compositions close to 0 per mil for the oxygen atoms in tropospheric peroxides derived from either molecular oxygen or water vapor.