INSIDE THE TOXIC CLOUD
How does city-wide smog form, and what damage can it cause?
Words by Scott Dutfield
DID YOU KNOW? In 2019, 21 of the top 30 most polluted cities in the world were in India
This is Fanhe Town in Tieling, China. These images were taken ten days apart during a passing smog cloud and after it had dispersed
Source: Wiki © Tomskyhaha
Air
pollution is one of the most pressing environmental issues in decades, with the World Health Organization estimating that it contributes towards around 7 million premature deaths worldwide each year. Burning fossil fuels, car emissions and agricultural activity are some of the biggest culprits in polluting our air. This pollution is typically measured and presented as a particulate matter 2.5 (PM
2.5
) value. This is the size of fine particulate matter in the air that measures up to 2.5 microns in size. The higher the
2.5
value, the worse the air quality is in a city or country. The build-up of these PM particulates can result in one of two types of dense smog, the most common of which is known as industrial smog.