Integrated Chemistry of Ozone in the Atmosphere (ICOZA)

Lead Research Organisation: University of East Anglia
Department Name: Environmental Sciences

Abstract

Tropospheric ozone is an important air pollutant, harmful to human health, agricultural crops and vegetation. It is the main precursor to the atmospheric oxidants which initiate the degradation of most reactive gases emitted to the atmosphere, and is an important greenhouse gas in its own right. As a consequence of this central role in atmospheric chemistry and air pollution, the capacity to understand, predict and manage tropospheric ozone levels is a key goal for atmospheric science research. This goal is hard to achieve, as ozone is a secondary pollutant, formed in the atmosphere from the complex oxidation of VOCs in the presence of NOx and sunlight, and the timescale of ozone production is such that a combination of in situ chemical processes, deposition and transport govern ozone levels. Uncertainties in all of these factors affect the accuracy of numerical models used to predict current and future ozone levels, and so hinder development of optimal air quality policies to mitigate ozone exposure. Here, we will address this problem by measuring the local chemical ozone production rate, and (for the first time) perform measurements of the response of the local atmospheric ozone production rate to NOx and VOC levels - directly determining the ozone production regime.

We will achieve this aim by building upon an existing instrument for the measurement of atmospheric ozone production rates (funded through a NERC Technology Proof-of-Concept grant, and deployed in the recent ClearfLo "Clean Air for London" NERC Urban Atmospheric Science programme). In addition to directly measuring ozone production, by perturbing the ambient chemical conditions (for example, through addition of NOx or VOCs to the sampled airflow), and measuring the effect of this change upon the measured ozone production rate, the ozone control regime (extent of NOx vs VOC limitation) may be directly determined. Within this project, we will develop our existing ozone production instrument to include this capability, and validate the measurements, through comparison with ozone production from VOC oxidation in a large simulation chamber, and by measurement of the key oxidant OH radicals, and their precursors, within the system.
We will then apply the instrument to compare the measured ozone production rates with those calculated using other observational and model approaches, and to characterise the ozone control regime, in two contrasting environments: In the outflow of a European megacity (at Weybourne Atmospheric Observatory, WAO, in the UK), and in a rural continental location (at Hohenpeissenberg, HPB, in southern Germany). At WAO, we will compare the measured ozone production rate with that calculated through co-located measurements of HO2 and RO2 radicals (using a newly developed approach to distinguish between these closely related species), and with that simulated using a constrained photochemical box model. We will compare the NOx-dependence of the ozone production rate with that predicted using indicator approaches, based upon observations of other chemical species. At HPB, we will focus upon the VOC-dependence of the ozone production rate, and assess the error in model predictions of ozone production, which arise from the presence of unmeasured VOCs.

The project will develop and demonstrate a new measurement approach, and apply this to improve our understanding of a fundamental aspect of atmospheric chemical processing. Future applications have considerable potential both to support atmospheric science research, but also as an important air quality tool, alongside existing measurement and modelling approaches, to inform the most effective emission controls to reduce ozone production in a given location. In the context of global crop yield reductions arising from ozone exposure of 7 - 12 % (wheat), 6 - 16 % (soybean) and 3 - 4 % (rice), this is an important societal as well as scientific goal.

Planned Impact

The project will deliver new scientific insight into our current understanding of atmospheric ozone formation, and quantify the systematic errors present in model predictions of ozone formation from unmeasured species and/or incomplete chemical understanding. It will also provide a new measurement capability to quantify local ozone production rates, and to directly establish the prevailing ozone control regime. Accordingly we identify two key groups of immediate beneficiaries :

-Research scientists studying all aspects of atmospheric ozone chemistry, and impacts of ozone upon climate, vegetation and human health.

-The air quality community, and policy makers involved in the development and formulation of air pollution control measures.

We will ensure the impact of the project to these groups is maximised through the following specific activities, alongside traditional dissemination routes (conferences, journal publications) :

(1) Direct liaison with the relevant atmospheric science research community, leveraging the PIs ongoing links to a range of relevant projects and groupings such as NCAS, TF HTAP

(2) Direct dissemination of the project results, and new measurement capability, to the Air Quality community, through our links to bodies such as AQEG

(3) By holding a focussed discussion workshop on the topic of "Local Chemical Ozone Production" disseminate the project science outcomes, leading to the preparation of a position paper reviewing the state of our understanding in this area.

(4) By convening a forum for the knowledge exchange over capabilities and needs in atmospheric measurement, between the atmospheric science research community, air quality monitoring practitioners, and those at the interface between atmospheric research and air quality policy, supported by the IAQM and learned societies.

Wider Beneficiaries: Scientific Community; General Public

The research proposed here will lead, both directly and through improved general scientific understanding, to improved ozone control strategies / policies. This will benefit the general public, as tropospheric ozone is a key pollutant, harmful to health, reducing crop yields, damaging materials and contributing to climate change. The outcomes of this work will therefore address two of the key RCUK definitions of impact, namely "increasing the effectiveness of public policy" and "enhancing quality of life and health".

Publications

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Sherwen T (2017) Effects of halogens on European air-quality. in Faraday discussions

 
Description An intensive field campaign was carried out at the Weybourne Atmospheric Observatory during June/July 2015. In early July the UK experience a heatwave and very high concentrations of ozone that are dangerous to human health were recorded. Using a 3-D regional model (WRF-Chem) we now have an improved understanding of the causes of this ozone event, in particular the source of many of the ozone precursors coming from continental Europe. We have also quantified the contribution that different regions within Europe and beyond made to ozone in the UK during the whole of summer 2015, illustrating the importance of long-range transport of from outside of Europe.
Exploitation Route Understanding the causes of high ozone in the heatwave will inform UK and EU policy makers. Furthermore, recognising the need to limit ozone concentrations on a hemispheric scale is important for the UK to reduce the impact of ozone on human health and vegetation. This is being fed to Defra via its Air Quality Expert Group.
Sectors Agriculture, Food and Drink,Education,Environment,Healthcare,Government, Democracy and Justice

 
Description A TV interview during the ICOZA campaign provided the public with information on ozone pollution in the East Anglia region. Gave a talk to the British Lung Foundation Norwich Breathe Easy support group - discussed trends in air quality and factors that led to air pollution.
First Year Of Impact 2015
Sector Environment
Impact Types Societal

 
Description University of East Anglia - partial studentship
Amount £27,303 (GBP)
Organisation University of East Anglia 
Sector Academic/University
Country United Kingdom
Start 10/2016 
End 03/2018
 
Title ICOZA Field Campaign WAO 
Description Data collected on reactive species during a 6 week campaign in June/July 2015 at the Weybourne Atmospheric Observatory (WAO). 
Type Of Material Database/Collection of data 
Year Produced 2015 
Provided To Others? Yes  
Impact Data being used for scientific interpretation by ICOZA consortium. 
 
Description Interview for newspaper article on air pollution event 
Form Of Engagement Activity A press release, press conference or response to a media enquiry/interview
Part Of Official Scheme? No
Geographic Reach Regional
Primary Audience Media (as a channel to the public)
Results and Impact Interviewed for the EDP regarding high levels of pollution in Norwich and across the S.E. of England. Quote from me appeared in the article warning people of a high air pollution episode.
Year(s) Of Engagement Activity 2017
URL http://www.edp24.co.uk/news/politics/government_issues_health_warning_as_air_pollution_reaches_highe...
 
Description Newspaper interview regarding the High Court judgement on air quality. 
Form Of Engagement Activity A press release, press conference or response to a media enquiry/interview
Part Of Official Scheme? No
Geographic Reach Regional
Primary Audience Media (as a channel to the public)
Results and Impact Interview for the Eastern Daily Press regarding the High Court judgement that the Government is not doing enough to improve air quality.
Year(s) Of Engagement Activity 2016
URL http://www.edp24.co.uk/news/politics/norwich_air_pollution_how_we_re_being_let_down_in_the_battle_ag...
 
Description Radio interview on air pollution 
Form Of Engagement Activity A press release, press conference or response to a media enquiry/interview
Part Of Official Scheme? No
Geographic Reach Regional
Primary Audience Media (as a channel to the public)
Results and Impact This was an interview on BBC Radio Norfolk linked to a news item on air quality standards not being met in King's Lynn. It will have informed public debate.

Unknown.
Year(s) Of Engagement Activity 2014
 
Description Radio interview regarding High Court judgement on air quality 
Form Of Engagement Activity A press release, press conference or response to a media enquiry/interview
Part Of Official Scheme? No
Geographic Reach Regional
Primary Audience Media (as a channel to the public)
Results and Impact Interview for BBC Radio Norfolk News regarding the High Court judgement that the Government is not doing enough to improve air quality.
Year(s) Of Engagement Activity 2016
 
Description TV interview at WAO 
Form Of Engagement Activity A press release, press conference or response to a media enquiry/interview
Part Of Official Scheme? No
Geographic Reach Regional
Primary Audience Public/other audiences
Results and Impact TV interview for an extended item for news programme on regional network. The item was about air pollution research in the region. The video was also distributed via the channels web page.
Year(s) Of Engagement Activity 2015
URL http://www.itv.com/news/anglia/update/2015-08-13/clearing-the-air-the-science-behind-our-weather/
 
Description TV interview on air pollution 
Form Of Engagement Activity A press release, press conference or response to a media enquiry/interview
Part Of Official Scheme? No
Geographic Reach Regional
Primary Audience Media (as a channel to the public)
Results and Impact This was a short interview on BBC Look East that was part of a larger news item on a large scale pollution event that was affecting much of the country. It will have informed public debate.

None known.
Year(s) Of Engagement Activity 2014
 
Description Talk to British Lung Foundation Breathe Easy Group 
Form Of Engagement Activity A talk or presentation
Part Of Official Scheme? No
Geographic Reach Local
Primary Audience Patients, carers and/or patient groups
Results and Impact Gave a presentation on air quality to the British Lung Foundations Norwich Breathe Easy patient support group. It as attended by people with lung conditions along with their relatives/carers. I discussed the trends in air pollution and factors leading to poor air quality. It sparked lots of questions and discussion. This is being followed up by an article for the quarterly newsletter.
Year(s) Of Engagement Activity 2018