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Welsh Government
Data Provider: Welsh Government Air Quality Indicators, by Local Authority
None
Year[Filtered]
Measure1
Pollutant[Filter]
Area[Filtered]
Click here to sortNO2Click here to sortPM10Click here to sortPM2-5
Wales324528
Isle of Anglesey153521
Gwynedd153522
Conwy203823
Denbighshire204024
Flintshire314327
Wrexham294327
Powys153723
Ceredigion143622
Pembrokeshire204124
Carmarthenshire204125
Swansea344428
Neath Port Talbot324528
Bridgend334528
Vale of Glamorgan344629
Cardiff575435
Rhondda Cynon Taf314529
Merthyr Tydfil284528
Caerphilly354730
Blaenau Gwent264428
Torfaen344730
Monmouthshire274628
Newport525433
Swansea Bay University Health BoardFrom 1st April 2019 health service provision for residents of Bridgend local authority moved from Abertawe Bro Morgannwg to Cwm Taf. The health board names have changed with Cwm Taf University Health Board becoming Cwm Taf Morgannwg University Health Board, and Abertawe Bro Morgannwg University Health Board becoming Swansea Bay University Health Board. These series are backdated to 2001 for the new areas.334528
Cwm Taf Morannwg University Health BoardFrom 1st April 2019 health service provision for residents of Bridgend local authority moved from Abertawe Bro Morgannwg to Cwm Taf. The health board names have changed with Cwm Taf University Health Board becoming Cwm Taf Morgannwg University Health Board, and Abertawe Bro Morgannwg University Health Board becoming Swansea Bay University Health Board. These series are backdated to 2001 for the new areas.314528

Metadata

Title

Air Quality Exposure Indicators

Last update

July 2022 July 2022

Next update

November 2023 (provisional)

Publishing organisation

Welsh Government

Source 1

Air Concentration, Department for Environment, Food and Rural Affairs

Source 2

Small area population estimates (SAPE), Office for National Statistics

Source 3

Geographical information, Welsh Government

Contact email

stats.environment@gov.wales

Designation

None

Lowest level of geographical disaggregation

Local authorities

Geographical coverage

Wales

Languages covered

English and Welsh

Data licensing

You may use and re-use this data free of charge in any format or medium, under the terms of the Open Government License - see http://www.nationalarchives.gov.uk/doc/open-government-licence

General description

Air Quality Exposure Indicators - average NO2, PM2.5 and PM10 concentrations across local authority areas and health board areas, derived from modelled data for each square kilometre in Wales, measured in µg/m3 (DEFRA data)

Data collection and calculation

Each year the UK Government’s Pollution Climate Mapping (PCM) model calculates average pollutant concentrations for each square kilometre of the UK. The model is calibrated against measurements taken from the UK’s national air quality monitoring network.

The Welsh Government has used this published data to assign a concentration of NO2, PM2.5 and PM10 to each residential dwelling in Wales based on which square kilometre of Wales it sits in.

For each census output area (statistical geographic units comprising around 150 properties), the pollutant concentrations associated with each dwelling within it were averaged to give an average NO2, PM2.5 and PM10 concentration across the census output area.

For each Local Authority and Local Health Board, a population-weighted average over its constituent census output areas were calculated to give an average NO2, PM2.5 and PM10 concentration based on where people live in those Local Authorities and Health Boards. The same calculation was also repeated over all census output areas, to give a comparable figure for the whole of Wales.


Frequency of publication

Annual

Data reference periods

Annual average

Users, uses and context

Information is used for local area air quality management and monitoring.

Rounding applied

Population weighted concentrations are rounded to the nearest whole number (µg/m3).

Revisions information

None.

Keywords

Air quality, pollution, air concentration

Statistical quality

See weblinks.
Each year the Pollution Climate Model (PCM) which underpin the background maps is refined and improved ( to account for latest available science and understanding e.g. changes in emissions factors, improved activity data etc.). These method changes are usually only applied in the latest year's figures.
2021 air quality figures are based on 2020 population estimates.