Air Quality data (2021)

Background pollution maps at 1x1 km resolution are modelled each year under Defra's Modelling of Ambient Air Quality (MAAQ) contract. These maps are used to provide policy support for Defra and to fulfil the UK's reporting obligations to Europe. They are also made publicly available for other research applications such as university studies, epidemiology and public health research, nature and conservation studies. The models are continually updated and improved and so the methodology often changes each year. The most recent methodology report is for 2020 and can be found on the UK-AIR website: Report (PDF). Users should be mindful of these year to year changes when comparing model outputs between years. Most of the model outputs are annual means, represented in µg m-3. CO concentrations are represented in mg m-3. Specific units and information about the different metrics is provided in the summary table below. Data available to download in csv format directly from UK Air Information Resource © Crown copyright 2021 Defra via uk-air.defra.gov.uk, licensed under the Open Government Licence.