Wind, rain and lockdown provide year-on-year boost to air quality

Michael Lewis, E.ON UK CEO
It is encouraging to see year-on-year improvements in average air quality levels, but research now shows air pollution levels are returning to their pre-lockdown peaks. No level of air pollution should ever be deemed safe and there is still work to do. 2020 has been an anomaly for many reasons and we must ensure we build on the momentum it has given us for cleaner air.
Michael Lewis, E.ON UK CEO

In continuation of its recently launched ‘Change the Weather’ service, E.ON has analysed the Daily Air Quality Index from Defra to uncover annual averages 

  • Average daily air pollution score improves by 2.9% in 2020 compared to 2019 
  • Improvements are due to less traffic during lockdowns and periods of wet and windy weather, according to meteorologist and clean air campaigner Clare Nasir 
  • E.ON launched its ‘Change the Weather’ service in early November to encourage national and regional media to include air quality information in daily weather forecasts 

Wind and rain are often sources of grumbles from sunshine-seeking Brits but new analysis1 of air pollution trends show we have something to thank the typical British weather for. Periods of wet weather during the summer, when combined with lower levels of traffic during national lockdowns, have helped improve the UK’s air quality scores by almost 3% year-on-year.

As part of its ongoing commitment to raise awareness about air pollution, E.ON reviewed the Defra Daily Air Quality Index (DAQI)2 for 2020 so far and compared it with the same period in 2019.

The DAQI provides daily scores out of 10 for air quality levels (10 being the worst air quality) and E.ON’s analysis found that the average figure across the UK for 2020 is 2.81 – an improvement of 2.9% on 2019’s average of 2.90.

This is despite the fact that there have been 498 ‘moderate’ air quality scores recorded this year – a score which means people with lung problems should consider reducing physical activity. There have also been 35 scores of ‘high’ or ‘very high’ levels of air pollution; levels at which older people and those with lung and heart problems are recommended to avoid strenuous physical activity altogether.

E.ON’s ‘Change the Weather’ service helps national and regional media to include Defra’s Daily Air Quality Index in their weather forecasts.

Michael Lewis, Chief Executive of E.ON UK, said: “It is encouraging to see year-on-year improvements in average air quality levels, but research3 now shows air pollution levels are returning to their pre-lockdown peaks. No level of air pollution should ever be deemed safe and there is still work to do. 2020 has been an anomaly for many reasons and we must ensure we build on the momentum it has given us for cleaner air.

“That’s why we’ve launched ‘Change the Weather’, with the goal of getting as many media outlets as possible to include air quality information in their weather forecasts. The more people are aware of the problem, the more they will think about the actions they can take to be part of the solution.”

Regionally, E.ON’s research shows there have been significant improvements over the course of the year, most notably in North East Scotland (18.8% improvement), the Highlands (8.6% improvement) and Yorkshire and Humberside (8.2% improvement). But at the same time, six regions saw a decline in air quality – particularly in North Wales, with a worsening of 9.5%.

Clare Nasir, a leading meteorologist and an ambassador for E.ON’s ‘Change the Weather’ campaign, explained what was driving the changes: “There are two reasons for the improvement in air quality in 2020. Firstly, lockdowns have helped a lot as people stayed indoors and the use of polluting means of travel, such as cars and aeroplanes, reduced significantly.

“The other contributing factor is the weather: wind and rain ultimately helped to improve air quality. While the first lockdown coincided with a dry and settled spell across the whole of the UK – which is usually conducive to higher levels of pollution – the period after restrictions were eased coincided with a wet June, and July 2020 was wetter than in 2019.

“These factors also likely explain the regional variations in the data. Because settled or anticyclonic conditions are conducive to poorer air and the heatwave of August 2020 lasted for longer in the South and Southeast, these areas had a mild decline in air quality. Meanwhile, Scotland saw a greater improvement in air quality with the onset of wet and windy weather from the middle of August. For North Wales, it’s possible that busy roads due to holidaymakers in the summer months contributed to the annual decline in air quality.”

E.ON’s Change the Weather service was launched after research4 revealed that almost two thirds (62%) of people say they miss how clear the air was during the first national lockdown. It also showed that nearly nine in ten (86%) believe air pollution is an issue the British public needs to know more.

E.ON makes it easier for people to tackle air pollution by providing 3.4 million customers’ homes and eligible small business customers with 100% renewable electricity at no extra cost5 and offering a range of sustainable solutions. For more information about how E.ON is helping to clear the air through smarter, sustainable energy solutions, and to learn more about ‘Change the Weather’, search E.ON Clean Air or visit eonenergy.com/clean-air.


Table one: Regional breakdown of annual air pollution averages


2019 average

2020 average



Improvement / Decline

North East Scotland








Yorkshire & Humberside




North East




South Wales




Central Scotland




East Midlands




North West & Merseyside




Northern Ireland




Scottish Borders




West Midlands



- 0.44%




- 0.49%

South West



- 0.60%

Greater London



- 0.64%

South East



- 0.87%

North Wales



- 9.51%

Source: E.ON Analysis of Defra Daily Air Quality Index

Notes to editor

  1. E.ON analysed the Defra Daily Air Quality Index scores for all 16 regions between 1 January and 17 November in 2019 and 2020
  2. The Defra Daily Air Quality Index (DAQI) tells you about levels of air pollution and provides recommended actions and health advice. For more information, go to http://uk-air.defra.gov.uk/
  3. Research from the Centre for Cities shows that air pollution now meets or exceeds levels before the start of the first lockdown, in 80% of places. See more here: https://www.centreforcities.org/publication/covid-pandemic-lockdown-air-quality-cities/
  4. Research conducted by Censuswide on behalf of E.ON with a survey of 4063 respondents
  5. Electricity backed by 100% renewable sources. All our customers' homes and eligible businesses get 100% renewable electricity, at no extra cost. Eligible businesses are SME customers that sign a contract directly with E.ON. Electricity sourced from E.ON’s renewable generation assets, supply agreements with independent UK wind generators and the purchase of renewable electricity certificates. The electricity supplied to homes and businesses comes from the National Grid and DNOs. eonenergy.com/renewable