New Breathe London data: Covid-19 confinement measures reduce London air pollution

Breathe London preliminary analysis results reveal substantial NO2 pollution reductions after the UK government implemented restrictions to reduce the spread of Covid-19, particularly after social distancing was strongly encouraged on 16 March. Although further work is needed to determine the precise magnitude of reductions, provisional results have been shared on the Breathe London website.

Data from the Breathe London network shows levels of NO2 lowering from around 18th March across Greater London.

The displayed plot shows Breathe London network NO2 measurements during 1 March to 13 April 2020. Each trace is an individual AQMesh monitor in the network and the thick black line represents the network average. The grey line represents upwind background from a rural site outside of London; elevated background readings indicate pollution from abroad. 

The full report from the Environmental Defense Fund gives details of when and where the greatest reductions were seen, plus an apparent association with traffic flow in London.

Detailed information on London’s air pollution is has been published on the Breathe London website since July 2019 as part of a collaborative project to paint a clearer picture of the city’s air quality. The readings are being provided by a network of AQMesh air quality monitoring pods, supplied and installed by Air Monitors, part of the ACOEM Group.