Air Pollution

Many of our daily activities create pollution and this is likely to affect us today and in the future, as well as causing changes in the weather.

Much of the pollution we produce is caused by invisible gases. Some of these create smog, a poisonous mist that develops over large cities such as Los Angeles. This is caused by gases emitted by cars, factories and power stations.

Local pollution

Is the air in your area polluted? You can find out by hanging a cloth outside. Firstly, cut a square from a piece of white cloth. Then stick a smaller square of cloth onto the middle of the first piece. Then hang the sheet outside for about a week. After that time, peel off the square in the middle. Is the area underneath cleaner?

This will give you an idea of how polluted the air in your local area is. Try placing the cloth in different places, such as in a park, by a road or near a factory or industrial area. What difference does this make?

However there is one main gas that is causing important changes in the Earth’s weather, and this is again released into the atmosphere by humans. This gas is carbon dioxide (CO₂), and causes what we know as the greenhouse effect.  We will learn more about the greenhouse effect on the next page.