Weather and Pollution

Weather plays an important role in spreading polluting gases and particulate matter. Local winds and air movement - due to heating and cooling in the atmosphere - carry the air pollution from one place to another.

Some winds are fairly fixed and move the pollution in the same direction each day. Other winds are turbulent, or very strong and unpredictable, and can cause the air pollution to spread over great distances. If there is no wind at all, pollutants can build up in one area.

Hot weather often sees an increase in smog and haze over our cities, as sunlight causes chemical reactions in the atmosphere to produce ozone.

Cooler weather often brings high levels of particulate air pollution, caused by burning fuel for heating. This is different from the smog and haze you see in summer, and is often called winter smog.

More information on Smog and Haze