Ubiquity of organic nitrates from nighttime chemistry in the European submicron aerosol

A. Kiendler-Scharr , A. A. Mensah , E. Friese , D. Topping , E. Nemitz , A. S. H. Prevot , M. Ńijälä , J. Allan , F. Canonaco , M. Canagaratna , S. Carbone , M. Crippa , M. Dall Osto , D. A. Day , P. de Carlo , C. F. Di Marco , H. Elbern , A. Eriksson , E. Freney (1, 2) , L. Hao , H. Herrmann , L. Hildebrandt , R. Hillamo , J. L. Jimenez , A. Laaksonen , G. Mcfiggans , C. Mohr , C. O'Dowd , R. Otjes , J. Ovadnevaite , S. N. Pandis , L. Poulain , P. Schlag , K. Sellegri (1) , E. Swietlicki , P. Tiitta , A. Vermeulen , A. Wahner , D. Worsnop , H. -C. Wu

1 OPGC - Observatoire de Physique du Globe de Clermont-Ferrand
2 LaMP - Laboratoire de Météorologie Physique

In the atmosphere nighttime removal of volatile organic compounds is initiated to a large extent by reaction with the nitrate radical (NO₃) forming organic nitrates which partition between gas and particulate phase. Here we show based on particle phase measurements performed at a suburban site in the Netherlands that organic nitrates contribute substantially to particulate nitrate and organic mass. Comparisons with a chemistry transport model indicate that most of the measured particulate organic nitrates are formed by NO₃ oxidation. Using aerosol composition data from three intensive observation periods at numerous measurement sites across Europe, we conclude that organic nitrates are a considerable fraction of fine particulate matter (PM₁) at the continental scale. Organic nitrates represent 34% to 44% of measured submicron aerosol nitrate and are found at all urban and rural sites, implying a substantial potential of PM reduction by NO_x emission control.

Mots clés: organic nitrate; particulate matter; field study

Domaines: Planète et Univers [physics]

A. Kiendler-Scharr, A. A. Mensah, E. Friese, D. Topping, E. Nemitz, et al.. Ubiquity of organic nitrates from nighttime chemistry in the European submicron aerosol. Geophysical Research Letters, 2016, 43, pp.7735-7744. ⟨10.1002/2016GL069239⟩. ⟨insu-03710555⟩