Reducing air pollution
As urban environments have many sources of pollution, such as road transport, city dwellers’ health is more at risk. The UK government has set a legal target to reduce the exposure of people to PM2.5 by 22% in 2028, compared with 2018 levels, and by 35% in 2040. This sets a new challenge for local authorities.
We generate long-term, high-frequency monitoring data of atmospheric composition, identify emission sources, and we model potential solutions. This delivers vital data needed to develop effective clean air policies and to monitor progress.
Trees as well as other vegetation inside and outside cities can remove pollution from the air. Our scientists use a combination of high-power computing and simpler model-based tools to calculate the amount of pollution that is removed by trees, as well as changes in pollutants like PM2.5 that people are exposed to on a daily basis. By combining this with health data, we can estimate an economic value for the health benefits that come from lower exposure to air pollution.
All vegetation types can remove pollution from the air, but trees are better at removing particulate matter, and this has health benefits to society which can be valued. The quantity of pollution removed and the associated health benefit vary around the country mainly due to the amount of tree cover, levels of pollution and population density.
This UK-focused tool allows users to explore the change in economic value resulting from new tree planting, or removal of existing trees within any local authority, based on its ability to remove PM2.5 pollution. Users can select a particular local authority area and can see relevant data on the total area, the area of woodland, and the human population, as well as the quantity of pollution removed, and that the long-term asset value of that service.
The pollution removal tool was developed by UKCEH with the environment economics consultancy eftec. Its latest improved version will be released in summer 2025. Join our mailing list to be informed!
Knowing the economic value of nature’s benefits can make the contribution of nature to livelihoods and economies visible, enabling smarter decisions that account for nature in our economic systems.
UKCEH scientists can help governments, local governments and businesses to calculate how air pollution removal by our trees and other natural habitats supports their economies. We developed the Natural Capital Account methodology used by UK Office for National Statistics (ONS) to report on health benefits of air pollution removal by habitats in the UK.
Read the 2024 UK natural capital accounts.
UKCEH monitoring activities cover atmospheric pollutants, including ammonia (NH3). As most ammonia emissions originate from agriculture, their tracking has historically focused on rural areas, but agricultural ammonia also contributes to higher concentrations of fine particulate matter (PM2.5) in cities. Other ammonia sources in towns and cities include road traffic and waste accumulation. Exposure to PM2.5 carries substantial health risks.
UKCEH manages the UK National Ammonia Monitoring Network, currently comprising 115 sites across the UK. We have operated the Network on behalf of Defra since 1996, which makes it one of the longest time series in the world. We are adding more urban monitoring sites to improve our understanding of urban ammonia sources and their impact on the chemical composition of urban aerosols in order to improve emission inventories.
UKCEH was a partner of the Integrated Research Observation System for Clean Air (OSCA) project which ran from 2019 to 2023 as part of the UK Clean Air Programme. The project gathered new data to provide a definitive assessment of the current state of UK urban air quality, and of trends in air pollutants. The research aims to inform policy makers’ and local authorities’ decisions to enable the development and optimisation of emission abatement measures for the protection of human and environmental health.
