Watch how air pollution moves across Europe
14 January 2019
This is what pollution looks like on a European scale - the animation shows the concentration and movement through the atmosphere of nitrogen dioxide.
NO2 is a problem gas that is produced primarily by vehicle exhausts and industrial activity via the burning of fossil fuels.
The map covers a sample period from 5 to 10 January, and describes the behaviour of NO₂ at ground level on an hourly basis. The worst air quality peaks in the white.
Source: BBC News
Image credit: DEFRA - What contributes most to roadside nitrogen oxide levels