Journal cover Journal topic
Atmospheric Chemistry and Physics An interactive open-access journal of the European Geosciences Union
https://doi.org/10.5194/acp-2017-713
© Author(s) 2017. This work is distributed under
the Creative Commons Attribution 4.0 License.
Research article
11 Aug 2017
Review status
This discussion paper is a preprint. It is a manuscript under review for the journal Atmospheric Chemistry and Physics (ACP).
Low modeled ozone production suggests underestimation of precursor emissions (especially NOx) in Europe
Emmanouil Oikonomakis1, Sebnem Aksoyoglu1, Giancarlo Ciarelli2, Urs Baltensperger1, and André S. H. Prévôt1 1Laboratory of Atmospheric Chemistry, Paul Scherrer Institute, Villigen, 5232, Switzerland
2Laboratoire Inter-Universitaire des Systèmes Atmosphériques (LISA), UMR CNRS 7583, Université Paris Est Créteil et Université Paris Diderot, Institut Pierre Simon Laplace, Créteil, France
Abstract. High surface ozone concentrations, which usually occur when photochemical ozone production takes place, pose a great risk to human health and vegetation. Air quality models are often used by policy makers as tools for the development of ozone mitigation strategies. However, the modeled ozone production is often not or not enough evaluated in many ozone modelling studies. The focus of this work is to evaluate the modeled ozone production in Europe indirectly, with the use of the ozone–temperature correlation for the summer of 2010 and to analyze its sensitivity to precursor emissions and meteorology by using the regional air quality model, CAMx. The results show that the model significantly underestimates the observed high afternoon surface ozone mixing ratios (≥ 60 ppb) by 10–20 ppb and overestimates the lower ones (< 40 ppb) by 5–15 ppb, resulting in a misleading good agreement with the observations for average ozone. The model also underestimates the ozone–temperature regression slope by about a factor of 2 for most of the measurement stations. To investigate the impact of emissions, three scenarios were tested: (i) increased VOC emissions by a factor of 1.5 and 2 for the anthropogenic and biogenic VOC emissions, respectively, (ii) increased NO emissions by a factor of 2, and (iii) a combination of the first two scenarios. For southern and central (except the Benelux area) Europe, doubling NOx emissions seems to be the most efficient scenario to reduce the underestimation of the observed high ozone mixing ratios without significant degradation of the model performance for the lower ozone mixing ratios. The model performance for ozone–temperature correlation is also better when NOx emissions are doubled. In the Benelux area, however, the third scenario (where both NOx and VOC emissions are increased) leads to a better model performance. The impact of meteorology was examined with two sensitivity tests: (i) increased surface temperature by 4 °C, and (ii) reduced wind speed by 50 %. Both scenarios lead to a consistent increase in all surface ozone mixing ratios, thus improving the model performance for the high ozone values but significantly degrading it for the low ozone values. Overall, the modeled ozone is predicted to be more sensitive to its precursor emissions (especially NOx) and therefore their uncertainties, which seem to be responsible for the model underestimation of the observed high ozone mixing ratios and ozone production.

Citation: Oikonomakis, E., Aksoyoglu, S., Ciarelli, G., Baltensperger, U., and Prévôt, A. S. H.: Low modeled ozone production suggests underestimation of precursor emissions (especially NOx) in Europe, Atmos. Chem. Phys. Discuss., https://doi.org/10.5194/acp-2017-713, in review, 2017.
Emmanouil Oikonomakis et al.
Emmanouil Oikonomakis et al.
Emmanouil Oikonomakis et al.

Viewed

Total article views: 192 (including HTML, PDF, and XML)

HTML PDF XML Total Supplement BibTeX EndNote
143 47 2 192 9 0 2

Views and downloads (calculated since 11 Aug 2017)

Cumulative views and downloads (calculated since 11 Aug 2017)

Viewed (geographical distribution)

Total article views: 192 (including HTML, PDF, and XML)

Thereof 192 with geography defined and 0 with unknown origin.

Country # Views %
  • 1

Saved

Discussed

Latest update: 22 Aug 2017
Publications Copernicus
Download
Short summary
We report a modelling study investigating the uncertainties in ozone production in Europe. Using various methods for different emission and meteorological scenarios, we searched for the possible reasons for underestimation of high ozone levels in Europe by models. Our results suggest that emissions, especially NOx, might be too low in the European inventories. Improvement of the modeled ozone production will contribute to more consistent and effective ozone mitigation strategies for the future.
We report a modelling study investigating the uncertainties in ozone production in Europe. Using...
Share