Diurnal variations in oxygen and nitrogen isotopes of atmospheric nitrogen dioxide and nitrate: implications for tracing NOx oxidation pathways and emission sources

Sarah Albertin (1, 2) , Joël Savarino (1) , Slimane Bekki (2) , Albane Barbero (1) , Roberto Grilli (1) , Quentin Fournier (3) , Irène Ventrillard (3) , Nicolas Caillon (1) , Kathy S. Law (2)

1 IGE - Institut des Géosciences de l’Environnement
2 TROPO - LATMOS
3 LIPhy - Laboratoire Interdisciplinaire de Physique [Saint Martin d’Hères]

The oxygen (∆¹⁷O) and nitrogen (∂¹⁵) isotopic compositions of atmospheric nitrate (NO₃⁻) are widely used as tracers of its formation pathways, precursor (nitrogen oxides NOx = nitric oxide NO + nitrogen NO2) emission sources, and physico-chemical processing. However, the critical lack of observations on the multi-isotopic composition of NO2 maintains significant uncertainties regarding the links between the isotopic composition of NOx and NO3−, which may bias estimates of the NO3− formation processes and the distribution of sources. We report here on the first simultaneous atmospheric observations of ∆¹⁷O and ∂¹⁵ in NO2 and NO₃⁻.

Domaines: Océan, Atmosphère

Sarah Albertin, Joël Savarino, Slimane Bekki, Albane Barbero, Roberto Grilli, et al.. Diurnal variations in oxygen and nitrogen isotopes of atmospheric nitrogen dioxide and nitrate: implications for tracing NOx oxidation pathways and emission sources. Atmospheric Chemistry and Physics, 2024, 24 (2), pp.1361-1388. ⟨10.5194/acp-24-1361-2024⟩. ⟨insu-04095457v2⟩