Why is the air quality bad today?
While many of us are enjoying the UK’s heatwave and rushing to sit outside and bask in the sun, with it can come higher pollution levels.
Defra data showed high levels of air pollution in much of the South East of England, especially Essex and Norfolk.
Other places such as Leeds, Sheffield, Kent and Sunderland are also facing high levels of pollution.
High pressure brings the pollutant particles into the UK but the still air means they are not swept away again.
When there is little breeze or wind to clear airborne pollutants away, it means the air quality gets worse.
In heavily populated areas, with a lot of traffic and little greenery, such as London, air quality can quickly deteriorate.
People have been urged to walk, cycle or use public transport to lessen the air pollution.
Mayor of London Sadiq Khan said it is particularly bad at the moment because we are “importing pollution from the continent” as well as local emissions building up.
He said: “Toxic air is extremely dangerous for Londoners – and I’m doing everything in my power to tackle it.
“This is particularly important in order to protect those who are more vulnerable to high pollution.”