Monitoring Air Pollution in Southampton and Reading
As part of its Air Day coverage, BBC South visited Southampton and Reading to explore how air pollution accumulates and the methods used to measure it.
The primary sources of pollution in the UK include local emissions such as road traffic, industrial activities, heating systems, and agricultural practices.
On windy days, pollution that accumulates can be dispersed by the wind; however, on calm days, especially during winter, pollution can become trapped near the earth's surface.
I met Simon Hartill, a scientific officer in Southampton City Council's environmental health department, at one of the council's four ground-based air monitoring stations.
At the station located on Brintons Road, near St Mary's Stadium, both the council and the Environment Agency monitor levels of nitrogen dioxide, sulphur dioxide, and other pollutants.
These pollutants are often produced by the combustion of fossil fuels such as petrol and diesel used in vehicles.
Southampton has three other automatic monitoring stations situated at Onslow Road, Victoria Road, and Redbridge Road. Additionally, smaller and more affordable diffusion tubes are deployed to monitor air quality in other parts of the city.
"[The Brintons Road station] is a very important site of the city because it's part of the government's national network," Hartill said.
"The automatic stations are very expensive, the analysers [cost] thousands of pounds. They're quite big so we can't put them everywhere, whereas the fusion tubes – they're quite cheap. We can put them up lampposts, outside people's houses and we've got about 80 in the city."
While humans breathe in oxygen, they also inhale small quantities of other gases and particles that can be detrimental to health.
Air Quality Forecasting in Reading
Melanie Ades, who works at the European Centre for Medium-Range Weather Forecasts (ECMWF) based at its Shinfield Park facility in Reading, explained the centre’s role.
"The way I like to think about it is it's like the UK Met Office but rather than forecasting weather across the UK, it forecasts air quality across Europe," she said.
The ECMWF also operates two other bases located in Bologna, Italy, and Bonn, Germany.
"There are two main ways which we measure air quality," she said. "[They are] Satellite observations, which are broad scale, global observations, and then you have local observations. In the UK, we are mainly affected by local emissions but we do have impacts from global situations."
Visible effects of pollution can be observed during major events, such as last year's forest fires in Canada or storms in the Sahara Desert that lifted dust and dispersed it across Europe and the UK.
Trends and Health Impacts of Pollution
Despite increased knowledge and awareness of pollution's effects, the presence of nitrogen dioxide and other pollutants has decreased both over the long term and in recent years.
Government data indicate that average nitrogen dioxide concentrations at roadsides and urban areas have been reduced by more than half since the late 20th century.
However, efforts to reduce pollution further remain important due to potential health impacts. Exposure to nitrogen dioxide can cause symptoms such as shortness of breath and coughing, with studies indicating that these effects are more significant for individuals with conditions like asthma.
