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Air Pollution. Pollution is the introduction of substances into the environment such that it results in unpleasant or damaging effects. Waste refers to materials that are no longer wanted.
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Pollution is the introduction of substances into the environment such that it results in unpleasant or damaging effects.
Air pollution – occurs when pollutants such as dust and smoke are released into the environment. • Haze is a result of dust and smoke particles suspended in the air.
Causes of pollution? ..caused by humans. ..caused by nature.
Causes of Air Pollution Natural causes a) Volcanic eruptions: • Large amounts of volcanic ash, smoke and gases are released during eruptions
20 million tons of volcanic ash and gas released into the atmosphere • Sunlight was blocked • Temperatures fall by 1 or 2 degrees for a few months
Causes of Air Pollution Natural causes b) Forest Fires • Occur naturally in times of prolonged hot and dry weather • High temperatures, low rainfall create dry conditions in forests.
Causes of Air Pollution Natural causes b) Forest Fires • Can be caused by people, such as when forests are cleared for agriculture or settlement
Human causes: • Industries • Power stations and manufacturing industries release large amount of dust and smoke into the air.
Human causes: • Industries • When fossil fuels are burnt in power stations, waste is also released into the air. Fine, black, carbon-based smoke particles called soot+ sulphur dioxide
Human causes: b) Motor vehicles - In urban areas, this is the greatest source of pollution.
Human causes: c) Construction work - Clearing of land, construction of buildings and transportation of construction materials pollute the air with dust and smoke particles.
Water vapour in the atmosphere which contains pollutants condenses to form clouds and eventually acid rain • River gets polluted by acid rain. (1) Harmful gases are released from industries, polluting the air. • (2) Wind picks up the harmful gases. • Acid rain falls into water bodies
Try explaining how the acid rain is formed without the captions!
Impacts of Air Pollution 1) Health problems 2) Traffic hazards 3) Environmental Problems
Impacts of Air Pollution Health problems • Dust and smoke can cause difficulty in breathing as well as irritations to people’s throats and eyes • Respiratory systems of people will be affected
Impacts of Air Pollution Traffic Hazards • Hard to see distant objects in air that is hazy • When countries experience a haze, airports may have to stop flights until visibility improves • Dangerous for those driving vehicles
Impacts of Air Pollution Environmental problems • Air pollution causes acid rain • Forests are destroyed • Living things in rivers are killed
Impacts of Air Pollution Environmental problems • Buildings are corroded
Air Pollution Causes Effects Human Factors NaturalFactors Environmental problems Health problems • Forest Fires • Volcanic Eruptions • Industries • Mobile transport • Construction work • Forest Fire Traffic Hazards
More industries, more money, more smoke: http://www.youtube.com/watch?v=hVCuZkMCa5k&feature=related • More cars, more smokehttp://www.youtube.com/watch?v=PxGdZEMzBuk&feature=related