Sources and methodology for constituency data

Introduction

Polling on importance of climate change to voters: Commitment to Climate Change: Survation Topical MRP Constituency Modelling on behalf of Greenpeace, September 2023. https://www.greenpeace.org.uk/resources/climate-opinion-poll/

Energy security and climate change

Flooding and extreme heat risks: University of Manchester on behalf of Friends of the Earth, 2022. friendsoftheearth.uk/climate/flooding-uk and policy.friendsoftheearth.uk/insight/who-suffers-most-heatwaves-uk

Excess deaths during winter: Small-area assessment of temperature-related mortality risks in England and Wales: a case time series analysis, The Lancet, 2022. (LSOA data provided by authors.) https://www.thelancet.com/journals/lanplh/article/PIIS2542-5196(22)00138-3/fulltext

One-fifth of excess winter deaths from cold homes: Fuel Poverty, Cold Homes and Health Inequalities in the UK, Institute of Health Equity, 2022. https://www.instituteofhealthequity.org/resources-reports/fuel-poverty-cold-homes-and-health-inequalities-in-the-uk

Number and proportion of homes in EPC bands DEFG. Energy Performance of Buildings Data: England and Wales data, Department for Levelling Up, Housing and Communities, 2023. https://epc.opendatacommunities.org/

Energy crisis hotspots data: Friends of the Earth, 2022. friendsoftheearth.uk/climate/new-research-reveals-nearly-9000-energy-crisis-hotspots-england-and-wales

Loft and wall insulation recommendations: Energy Performance of Buildings Data: England and Wales data, Department for Levelling Up, Housing and Communities, 2023. https://epc.opendatacommunities.org/

Pollution

Prevalence of respiratory diseases: Constituency data: health conditions, House of Commons, 2023. commonslibrary.parliament.uk/constituency-data-how-healthy-is-your-area/. This data is only available for England, not Wales.

Neighbourhoods with NO₂ and PM_2.5 levels above WHO guidelines: Friends of the Earth analysis of modelled background air pollution, 2022. uk-air.defra.gov.uk/data/pcm-data

Sewage spills: Event Duration Monitoring - Storm Overflows - 2023 (England and Wales), The Rivers Trust. https://data.catchmentbasedapproach.org/datasets/theriverstrust::event-duration-monitoring-storm-overflows-2023-england-and-wales/about. (Note: The Rivers Trust compiled this using Environment Agency data for overflows in England and data accessed from Dŵr Cymru/ Welsh Water and Hafren Dyfrdwy websites for overflows in Wales.)

Transport

Households without access to a car: Census 2021. www.nomisweb.co.uk/datasets/c2021ts045

Bus service trends: Friends of the Earth and University of Leeds analysis: Bus service trends 2010-2023. policy.friendsoftheearth.uk/insight/how-britains-bus-services-have-drastically-declined

Nature

Accessible green spaces: Green Infrastructure Map, Natural England, 2023. This data is only available for England, not Wales. https://designatedsites.naturalengland.org.uk/GreenInfrastructure/Map.aspx. We've calculated the area (m²) of accessible green space per capita on advice from Natural England. We've used this metric to split constituencies into 3 equal groups showing the distribution of green space across England, with the top third labelled as having "good" access to green space and the bottom third having "poor" access to green space. Using this method, constituencies are labelled as having "poor" access to green space where there's less than 27 m² of accessible green space per person.

It's important to recognise that we've used data on publicly accessible green space here, and that in most constituencies there's likely to be other green space that's not currently publicly and freely accessible and that could be opened up for wider access. We've also not included data on public rights of way that allow people to enjoy green spaces, but we aim to add this data to the next version. 

Number of neighbourhoods with tree canopy cover less than 10%. Terra Sulis on behalf of Friends of the Earth, 2022. This data is only available for England, not Wales. policy.friendsoftheearth.uk/insight/mapping-english-tree-cover-results-ranking-and-methodology

Jobs and the economy

The UK's net zero economy: Energy & Climate Intelligence Unit, February 2024. https://eciu.net/analysis/reports/2024/the-uks-net-zero-economy-2024 

Aggregating small area statistics to new political constituencies

The majority of statistics presented in the tool have used small area neighbourhood statistics (eg at LSOA or MSOA level) aggregated to constituency level. Sometimes small areas will straddle 2 or more constituencies. To work around this issue, we produced 2 types of lookup tables:

• Area-based lookups, where each dataset is weighted by the proportion of the neighbourhood area in each constituency. This method was used for area-based input data (eg tree cover data).
• Postcode-based lookups, where each dataset is weighted by the proportion of neighbourhood postcodes in each constituency. This method was used for demographic data. 

To produce the lookups, we identified what proportion of each small geographical area "sits" within each constituency. We then weighted each input dataset by these proportions, depending on the type of dataset, to find how much of the input quantity "sits" in each constituency.