ClearfLo: Clean Air for London

Lead Research Organisation: NERC Centre for Ecology and Hydrology
Department Name: Billett

Abstract

Poor air quality, particularly in urban areas, has a demonstrable effect on human health, but the processes responsible for producing the main pollutants, namely particulate matter, ozone, nitrogen dioxide and heat are not well understood and are poorly predicted. The ambition of ClearfLo is to provide integrated measurements of the meteorology, composition and particulate loading of London's urban atmosphere, made at street level and at elevated sites, complemented by modelling, to improve predictive capability for air quality. This ambition will be addressed by establishing new measurement capabilities in London, which will be used for long-term measurements and intensive observation periods, and by analysis and modelling of the measurements to establish key processes.

Publications

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Bohnenstengel S (2015) Meteorology, Air Quality, and Health in London: The ClearfLo Project in Bulletin of the American Meteorological Society

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Helfter Carole (2013) Carbon dioxide and methane emission dynamics in central London (UK) in EGU General Assembly Conference Abstracts

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Helfter Carole (2015) Sources of greenhouse gases and carbon monoxide in central London (UK) in EGU General Assembly Conference Abstracts

 
Description 1. Quantification of urban emission fluxes
Direct measurements of urban emissions of volatile organic compounds (VOCs) and nitrogen oxides in London, from the BT Tower and a rooftop site at the Kings College London, showed that:
(a) emissions of NOx are underestimated in the current London emission inventory, which is consistent with the underestimation of NOx emission factors from diesel engines;
(b) whilst some priority VOCs such as benzene are correctly predicted by the emission inventory, other compounds such as isoprene and methanol are either not included at all or underestimated.

2. Contribution of cooking to particulate matter in urban environments
A year-long time series of the chemical composition of fine dust (PM1) at Marylebone Rd, London, suggests that the local enhancement in PM1 due to cooking is as large as that from organic carbon compounds emitted by vehicles. A first upscaling of this contribution to the UK has produced the first assessment across the UK's urban centres.

3. ClearfLo work by the Univ. of York showed that long-chain hydrocarbons are an important, usually ignored, class of chemicals emitted by diesel engines. In collaboration with York and the Univ. of Edinburgh, we have included these compounds in a chemistry and transport model and demonstrated that it improves the models capability to reproduce the mesasured secondary organic aerosol concentrations.

2.
Exploitation Route Emission inventories need to be improved for NOx, VOCs and to include long-chain VOCs from diesel combustion for models to simulate better the urban atmospheric chemistry and impacts on human health and climate.

The work highlights the importance of cooking emissions for human exposure to particulate matter and opens up a relatively cost-effective way for government to reduce health effects.
Sectors Environment,Government, Democracy and Justice

 
Description ClearfLo has highlighted the importance of cooking aerosol and solid fuel burning as contributors to urban PM as well as identified interermediate-chaing VOCs from diesel emissions as a missing precursor of secondary organic aerosol. Together with emerging evidence from other studies, this has informed Defra's new Clean Air Strategy 2019, which now targets a much wider range of emissions in its attempt to lower PM exposure of the UK population.
First Year Of Impact 2019
Sector Environment,Government, Democracy and Justice
 
Description Integrated Research Observation System for Clean Air (OSCA)
Amount £2,438,169 (GBP)
Funding ID NE/T001798/1 
Organisation Natural Environment Research Council 
Sector Public
Country United Kingdom
Start 02/2019 
End 04/2022
 
Title Concentrations and meteorological data measured at Kings College site and on BT Tower during ClearFlo IOPs 
Description Concentrations of NH3 etc., as well as associated measurements on the BT Tower and Kings College site. 
Type Of Material Database/Collection of data 
Year Produced 2015 
Provided To Others? Yes  
Impact Used in larger analyses, bringing together numerous data streams to understand correlations between variables. 
URL http://www.clearflo.ac.uk/internal/data/
 
Title Eddy-covariance flux measurement system for aerosol chemical components 
Description Development of the Aerodyne high resolution time-of-flight aerosol mass spectrometer (HR-ToF-AMS) into a flux measurement system for PM1 chemical components, including hardware modifications, development of a fast data acquisition mode and flux processing routines. 
Type Of Technology New/Improved Technique/Technology 
Year Produced 2014 
Impact Underpinned flux measurements to quantify urban emissions and controls of dry deposition velocities of particles. 
 
Description Contribution to NERC 50th anniversary celebration abaord RRS Discovery 
Form Of Engagement Activity Participation in an activity, workshop or similar
Part Of Official Scheme? No
Geographic Reach National
Primary Audience Policymakers/politicians
Results and Impact We presented a poster on the verification of pollutant emissions from London at the CEH stall during the NERC 50th anniversary celebration aboard the RRS Discovery, which was based on NERC grant research. Depending on the day the audience included local and national policy makers, school children and other members of the public.
Year(s) Of Engagement Activity 2015
 
Description Presentation at the NERC Atmospheric Science Showcase at Cranfield 
Form Of Engagement Activity Participation in an activity, workshop or similar
Part Of Official Scheme? No
Geographic Reach National
Primary Audience Professional Practitioners
Results and Impact A presentation and a stall were contributed to the Atmospheric Science Showcase event in Cranfield which formed part of NERC's 50th anniversary celebrations.
Year(s) Of Engagement Activity 2015
 
Description Stall at the NERC Into-the-blue event, Manchester 
Form Of Engagement Activity Participation in an activity, workshop or similar
Part Of Official Scheme? No
Geographic Reach Regional
Primary Audience Public/other audiences
Results and Impact A stall was provided at the Into-the-blue event, Manchester, that included a practical demonstration the flux measurement approaches used for methane on the BT Tower, together with the a display of the results of the measurements and their implications.
Year(s) Of Engagement Activity 2016
 
Description Stall on the RRS Discovery to mark NERC's 50th birthday 
Form Of Engagement Activity Participation in an activity, workshop or similar
Part Of Official Scheme? No
Geographic Reach National
Primary Audience Policymakers/politicians
Results and Impact A stall was provided for the NERC 50th Anniversary celebrations on the RRS Discovery in London which highlighted the BT Tower flux measurements and their findings.
Year(s) Of Engagement Activity 2015
 
Description UnEarthed 
Form Of Engagement Activity Participation in an activity, workshop or similar
Part Of Official Scheme? No
Geographic Reach Regional
Primary Audience Public/other audiences
Results and Impact Stall titled "Air Pollution and Us" at the NERC UnEarthed event at the Edinburgh Dynamic Earth, 17-20 Nov 2017. It was very well received by school children and the wider public, who learnt about our research and the research methods used.
Year(s) Of Engagement Activity 2017