Air quality tests need simplifying to help reduce dangerous emissions
New methods of testing and simulating air quality should be considered in order to help policy makers have a more accurate understanding of how emissions affect air pollution levels, new research suggests.
In a review published in the Journal of the Air & Waste Management Association, the authors claim that current air quality modelling systems used in the US to perform simulations to help us understand how pollutants react in the atmosphere need to strike a balance between sufficient chemical detail and needless speculation to produce accurate results to help improve air quality.
The new paper provides recommendations for how to produce more accurate descriptions of atmospheric chemical reactions, and in-turn air quality simulations, in the fight to reduce dangerous emissions.
The production of air pollution from motor vehicles, industrial power plants, and fossil fuel emissions are determined by complex chemical reactions. To accurately simulate air pollution, air quality models solve sets of equations that mathematically describe the physical and chemical processes regulating the fate of emissions in the atmosphere. Lead author Professor William Stockwell from the University of Texas at El Paso explains, accurate simulations of air pollutants require updated and accurate descriptions of the chemical processes for the changing chemical regimes of the atmosphere and emerging contaminants of concern.
Researchers compared current techniques used to describe atmospheric chemical reactions against more historical techniques. They focused their comparison on techniques used in a three-dimensional model commonly used by environmental agencies to simulate ozone, particulate matter, and atmospheric acid concentrations, and develop effective emission reduction strategies.
According to the review, early development (1970–2000) of techniques for describing atmospheric chemical reactions involved adding a chemical reaction one-by-one to the mathematical description, each followed by laboratory testing using an environmental chamber, and comparing the simulations with the results. “We consider this to be a “bottom-up” approach,” says Stockwell.
In comparison, the current techniques for describing atmospheric reactions are referred to as a “top-down” approach and involve first creating highly complex mathematical descriptions of chemical reactions prior to testing and then later simplifying them for their use in an air quality model.
The researchers were both surprised and concerned to find that the top-down approach has been widely advocated to the exclusion of the “bottom-up” approach” for updating the descriptions of the chemistry used for air quality modeling.
Stockwell argues that starting the development of the mathematical description of the chemistry with a very large number of reactions that are not well tested in the laboratory, may add an unnecessary amount of uncertainty to the description of the chemistry in the model that, in turn, may impact a model’s effectiveness at simulating air pollution.
Instead, the researchers suggest that air quality models would be more accurate if the descriptions of atmospheric chemical reactions were developed through a combination of bottom-up and top-down techniques, i.e., adding a reaction or small group of reactions to the mathematical description (bottom-up technique), followed by testing against more complex mathematical descriptions (top-down) and a final simplification for air quality model input.
The researchers also recommend that more attention should be given to alternative techniques to produce the sets of equations that mathematically describe the chemical processes for air quality modeling, such as the use of informatics and air quality modeling systems that better characterize the uncertainty in their simulations.
NOTES
For a copy of the study, please visit the Taylor & Francis Newsroom Embargo Area: https://newsroom.taylorandfrancisgroup.com/embargoed-releases/
To arrange an interview, please contact:
Name: William Stockwell
Phone: + 1 775-674-7003
Email: William.R.Stockwell@gmail.com
For more information, please contact:
Krystina Sihdu, Press & Media Executive
Email: newsroom@taylorandfrancis.com
Tel.: +44 (0)20 7017 6928
Follow us on Twitter: @tandfnewsroom
The article will be freely available once the embargo has lifted via the following link: http://tandfonline.com/10.1080/10962247.2019.1694605
About Taylor & Francis Group
Taylor & Francis Group partners with researchers, scholarly societies, universities and libraries worldwide to bring knowledge to life. As one of the world’s leading publishers of scholarly journals, books, ebooks and reference works our content spans all areas of Humanities, Social Sciences, Behavioural Sciences, Science, Technology and Medicine.
From our network of offices in Oxford, New York, Philadelphia, Boca Raton, Boston, Melbourne, Singapore, Beijing, Tokyo, Stockholm, New Delhi and Cape Town, Taylor & Francis staff provide local expertise and support to our editors, societies and authors and tailored, efficient customer service to our library colleagues.
About Journal of the Air & Waste Management Association
J&AWMA is one of the oldest continuously published, peer-reviewed, technical environmental journals in the world. First published in 1951 under the name Air Repair, J&AWMA is intended to serve those occupationally involved in air pollution control and waste management through the publication of timely and reliable information.
Vision
To be the leading technical communicator for policy-relevant air and waste management science and technology.
Mission
To provide A&WMA and the general public with descriptions of timely, contemporary advances in air quality and waste management science and technology for use in improving environmental protection.
TECHNICAL EDITOR-IN-CHIEF
Trivikrama Rao
North Carolina State University, USA
strao@ncsu.edu