The monitoring station in a city showed the results. It seems VOC level is also high when ozone measurement is high.
Mechanism discussions and experiences are sincerely welcome.
Ground-level ozone is a so-called secondary pollutant, i.e. is not emitted directly but formed by complex photochemistry. The main ozone precursors are nitrogen oxides (NOx) and VOCs, both of which are abundant in an urban setting (which seems to be your case). A good starting point to get your bearings is in this link http://www-personal.umich.edu/~sillman/ozone.htm#OZO1.3, which discusses the photochemical pathways leading to ozone formation when NOx and VOCs are present.
Mitigation strategies to reduce ozone depend crucially on the relative abundances of the two precursors, so you first need to figure out whether you are in a NOx-limited or VOC-limited situation. In the first case, reducing NOx emissions would lead to ozone reductions, in the second case you'd have to reduce VOC emissions to see a decrease in ozone. Ideally you would build an ozone isopleth (Figure 1.2 in the link above) for your monitoring station and this would advise you on the best mitigation strategy.
Also bear in mind that there may be other factors at play, including meteorology, seasonality and transport of air masses.
This can be fairly easily understood on the basis of the empirical ozone isopleths, showing ozone as a function of VOCs and NOX, its chemical precursors. (see for example Air Pollution (Chapter 11) - of the book Urban Climates (doi 10.1017/9781139016476) . In this diagrams ozone appears as hyperboles parametric of ozone in a field of VOCs concentration vs. NOx , wherein you can easily catch the sense of how ozone depends on both these families of chemical precurorss. This means that you can control ozone accumulation controlling first the emission of its precursors and that the decrease of one family may leat to a limitationof ozone production owing to insufficient amount of the other family. This approach can solve your question at least at an intuitive level. However ozone problem is a very hard one to solve as in an urban environment there is a mix of biogenic and anthropogenic sources of precursors which are difficult to manage in the practice. In any case my advice is to try to understand thoroughly the chemistry behind using a reference text such as the text by Seinfeld and Pandis, a must in atmospheric science. It will take some time to swallow but it is worth. To date nobody has actually succeeded in controlling ozone which has an increasing trend in the troposphere since several decades.
Boris Rewald,
Thanks for providing the useful article related to my question.
high level of nitrogen may be associated with O3 increase level
https://aaqr.org/articles/aaqr-10-07-oa-0055.pdf
https://www.hindawi.com/journals/amete/2013/469786/
https://austinpublishinggroup.com/environmental-sciences/fulltext/aes-v1-id1001.php
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