Cold weather and very light winds have today (January 20) led to a build up high particulate air pollution being recorded in several parts of London and Birmingham.
The situation has prompted charities Asthma UK and the British Lung Foundation to warn those with asthma and lung conditions to “take extra care” , while Barnet and Harrow’s GLA-funded Cleaner Air Project warned residents to take “precautions” and “quieter routes” when travelling in the capital.
Monitoring stations in the likes of Camden, Harringey, Kensington, Ealing, Southwark and on the busy Marylebone Road in London are today averaging high levels of particulate matter in excess of 50ugm3 (microgrammes per cubic metre) and in some cases as high as 80ugm3.
Meanwhile, high – between 7 and 9 on the scale – levels of both PM2.5 (fine particles) and PM10 (particles up 10 micrometers in diameter) are currently being recorded at the Birmingham Tyburn roadside air quality monitoring station.
Moderate particulate levels are also being recorded in the likes of Stoke-on-Trent, Coventry and other parts of the East and West Midlands, as well as South East and South West England, today.
However, official public health pollution alerts are only issued by the government for high levels of nitrogen dioxide, ozone or sulphur dioxide pollution, and not for particulates.
Defra has therefore today instead only issued ‘notifications’ on its air monitoring website that stations are measuring high particle levels in Birmingham and London.
It comes as local authority representatives faced questions in Westminster from MPs on Parliament’s EFRA Committee, with the government taking criticism for its national air quality policy.
According to Defra forecasts for today, settled conditions and very light winds “may lead to the build-up of locally emitted pollution”.
Moderate levels are then expected to remain in some local areas tomorrow (January 21) due to light morning winds, but the situation is expected to subside with levels returning to low by the afternoon.
However, the London Air website for the monitoring network operated by King’s College London (KCL) expects high air pollution levels to remain across the UK capital tomorrow, pointing to the likelihood of an additional rise in nitrogen dioxide levels.
Moderate NO2 levels were already monitored at various London sites during this morning’s rush hour, and it is “likely we will again see widespread moderate NO2 during the evening rush hour with a chance of high NO2 at some very busy roadside locations” according to KCL.
Morning rush hour
The KCL forecast for tomorrow then suggests that a very cold start with some frost and light winds will likely mean “widespread” moderate nitrogen dioxide levels during the morning rush hour “with the chance of high at some very busy roadside locations across London”.
It states: “Through the day (January 21), the wind will move to a southerly direction picking up slightly. Back trajectory analysis shows the air arriving at the south-east on Thursday has travelled through industrialised and urban parts of Europe over the last three days picking up emissions.
“This will add to London’s already elevated pollution concentrations, and we are therefore likely to see widespread ‘high’ particulate pollution across the city with an outside chance of ‘very high’ at some very busy roadside locations.”