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.

• 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.

• Dust + Smoke + Water Vapour + Toxic gases

=

Smog

Causes of pollution?

Human

Natural

..caused by

humans.

..caused by

nature.

Causes of Air PollutionNatural causesa) 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 PollutionNatural causesb) Forest Fires - Occur naturally in

times of prolonged hot and dry weather

- High temperatures, low rainfall create dry conditions in forests.

Causes of Air PollutionNatural causesb) Forest Fires - Can be caused by people, such

as when forests are cleared for agriculture or settlement

Human causes:a)Industries- Power stations and

manufacturing industries release large amount of dust and smoke into the air.

Human causes:a) 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.

(1) Harmful gases are released from industries, polluting the air.

(2) Wind picks up the harmful gases.

• Water vapour in the atmosphere which contains pollutants condenses to form clouds and eventually acid rain

• Acid rain falls into water bodies

• River gets polluted by acid rain.

Try explaining how the acid rain is formed without the

captions!

Impacts of Air Pollution

1) Health problems

2) Traffic hazards3) Environmental

Problems

Impacts of Air PollutionHealth 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 PollutionTraffic 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 PollutionCause

sEffects

Human Factors

Natural Factors

1) Industries2) Mobile

transport3) Construction

work4) Forest Fire

1) Forest Fires2) Volcanic

Eruptions

Traffic Hazards

Health problems

Environmental problems

Air pollution caused by motor vehicles and industries

• 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