Every day, the average person inhales about 20,000 litres of air. Human activities also release substances into the air, many of which are harmful to us as well as to plants and animals. This air pollution comes in the form of both gases and particles. Examples of gases are sulphur dioxide, carbon monoxide and nitrogen oxides – mostly from the burning of fossil fuels, and chemical vapours from many of the products we produce. The exhaust from burning fuels in automobiles, homes (including fireplaces), and industries is also a major source of particles.
Air is also vital for maintaining and transferring heat around the Earth. Human activity produces greenhouse gases such as carbon dioxide and methane, which trap heat in the atmosphere. This excess heat is causing disruptions in many ecosystems and altering the normal patterns of heat movement in the atmosphere. The latter is likely playing a role in much of the severe and erratic weather we have seen in the last several years.
This section provides information on how to reduce the harmful effects on the air that result from our everyday activities.