Open zarino opened 1 year ago
Mike at FoE let us know that they’ve recently published more up-to-date air quality data, "using data released by DEFRA last week and data on energy efficiency and tree cover" – worth checking whether this is any better that what we’ve currently got. Although, sadly, it’ll be England and Wales only. https://policy.friendsoftheearth.uk/download/environmental-data-political-constituency
Mike and Toby from FoE, and I, had a short discussion about air quality data before Christmas, and they shared how they compare LSOA air quality figures to WHO guidelines to make them easier to understand. Toby from FoE has shared their data on this, for current constituencies – I’ve put it into the shared drive.
I note that DEFRA now lists 2022 shapefile data on the page where we previously got 2021 data: https://uk-air.defra.gov.uk/data/pcm-data, so we could update that too, at the same time as comparing with WHO guidelines. /cc @alexander-griffen
@juliacush and I discussed this yesterday, in reference to https://github.com/mysociety/local-intelligence-hub/pull/520. We were trying to work out the most useful way to incorporate the WHO guidelines, to give users context on what "good" or "bad" pollution numbers look like.
It’s worth noting that only three of the pollutants available to us have comparable WHO guidelines:
Pollutant | DEFRA data units | WHO 2021 guideline | Comparable? |
---|---|---|---|
PM2.5 | annual mean, μg/m3 | annual mean, 5 μg/m3 | ✅ |
PM10 | annual mean, μg/m3 | annual mean, 15 μg/m3 | ✅ |
NO2 | annual mean, μg/m3 | annual mean, 10 μg/m3 | ✅ |
SO2 | annual mean, μg/m3 | 24-hour mean, 40 μg/m3 | ❌ |
O3 (Ozone) | days with max 8-hr concentration greater than 120 μg/m3 | 10 μg/m3 | ❌ |
@juliacush and I discussed that one way we could ground the constituency numbers against the WHO guidelines (in a numeric way, that can be used in filters and tables, rather than just through shading) would be to calculate the ratio of the constituency’s value and the corresponding WHO guideline value, perhaps as a percentage. eg:
Constituency | PM2.5 | WHO guideline | Ratio |
---|---|---|---|
Cardiff Central | 9.17 μg/m3 | 5 μg/m3 | 183% |
North Devon | 5.35 μg/m3 | 5 μg/m3 | 107% |
Argyll and Bute | 2.53 μg/m3 | 5 μg/m3 | 51% |
To keep the raw pollutant numbers accessible to specialist campaigners who want to filter by a specific number (for example, the government’s target of 10 μg/m3 of PM2.5) these percentages could be displayed as their own separate dataset – "Air pollution: As a % of WHO health guidelines" or similar.
The question, then, becomes whether exposing three different figures for air quality (PM2.5, PM10, and NO2) is simple enough – or whether we dare to average them together into a single (very rough) overall pollution ratio. Scientists would probably balk at the idea, but if our aim is to give non-specialists a single indicator of "is air quality a problem in this constituency" maybe it’s worth it?
James from Democracy Network suggested, if we need anyone to sense-check our plans for displaying air quality data, we should contact Simon Birkett at Clean Air in London.
From Mary:
Beth shared a link to addresspollution.org, which says of its source data:
It’d be great to find an up-to-date source of air quality / pollution data per constituency.