There are lots of different types of pollution – can you name a few? The pictures below show a few examples.
In our research, we focus on air pollution. Air pollution is defined as the contamination of the air by particles and gases that can be harmful to human health and the environment.
Air pollution can be caused by human activity (e.g. emissions from factories or cars) or natural processes (e.g. forest fires or volcanic eruptions).
Air pollution caused by human activity is much easier for us to control and so it is the focus of most of our research.
Do you recognise the event shown in the picture below?
The image shows ‘smog’. The word ‘smog’ was first used in the 1900’s and, as a combination of ‘smoke’ and ‘fog’, was used to differentiate between natural mist/fog and that created by excessive air pollution in the atmosphere. These days, factories burn less solid fuel (like coal) and so generate less smoke. However, we still get smog – why is this? Today, the smog we see is known as photochemical smog which is produced when sunlight reacts with pollutants in the atmosphere (remember the photolytic reactions we talked about in the last section?)
Smog is usually associated with poor air quality in places like China where frequent smogs mean people may wear masks to protect themselves or even stay inside on particularly bad days to avoid the air pollution. However, it’s important to remember that we also see significant smog events in places like London and Krakow (a major city in Poland).
Smog is a useful example of air pollution as we can see it however, most impacts of air pollution are not visible in our everyday life as lots of these harmful gases are colourless and odourless. There are many other more subtle effects of air pollution including: