What is Air Pollution??
· Air pollution occurs when the air contains gases, dust, fumes or odour in harmful amounts. That is, amounts which could be harmful to the health or comfort of humans and animals or which could cause damage to plants and materials.
The substances that cause air pollution are called pollutants. Pollutants that are pumped into our atmosphere and directly pollute the air are called primary pollutants. Primary pollutant examples include carbon monoxide from car exhausts and sulfur dioxide from the combustion of coal.
What are the causes??
· Carbon dioxide is one the main pollutants that causes air pollution. This is because, although living beings do exhale carbon dioxide, this gas is harmful when emitted from other sources, which are caused due to human activity.
· Carbon monoxide is another such gas which, although was present in the atmosphere earlier, is now considered to be a major pollutant.
· Sulfur dioxide is yet another harmful pollutant that causes air pollution. Sulfur dioxide is emitted largely to the excessive burning of fossil fuels, petroleum refineries, chemical and coal burning power plants etc. Nitrogen dioxide when combined with sulfur dioxide can even cause a harmful reaction in the atmosphere that can cause acid rain..
What are the effects??
· smog, acid rain, carbon monoxide, fossil fuel exhausts, and tropospheric ozone are all examples of air pollution.
· Air pollution is made up of solid particles and chemicals. Natural processes impacting the atmosphere include volcanoes, biological decay, and dust storms. Plants, trees, and grass release volatile organic compounds , such as methane, into the air.
· The atmosphere is a complex, dynamic and fragile system. Concern is growing about the global effects of air pollution, especially climate change. Stratospheric ozone depletion due to air pollution has long been recognized as a threat to human health.
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