Physical Geography 101
Pollution


Air Pollution

What is air pollution?

Brief History of Air Pollution

First human produced air pollution:
Early accounts of air pollution:
In 1273, King Edward I Longshanks of England banned the use of sea coal.
- the first "Clean Air Act"
By 1850 the Industrial Revolution had started in Europe and North America
London became known for its "pea-soup" fog - not a true fog, but a mixture of fog and smoke
In 1873 one such fog killed 700 people
In 1911 another killed 1150 people
- at this time a London physician, Harold Des Voeux, coined the term "smog" - smoke and fog
In 1952 nearly 4000 people died in one of the killer smogs.
Great Britian passes its first Clean Air Act in _____.
United States passes its first Clean Air Act in _____.

Types and Sources of Air Pollutants

Carbon Monoxide - CO
A colorless, odorless, poisonous gas
Sources:
Dangerous because red blood cells will more readily carry CO than oxygen, O2

Sulfur Dixide - SO2
Colorless gas, produced by combustion of sulfur bearing fossil fuels (coal, oil)
Primary sources:
Natural sources:

Nitrogen Oxides - NOx
Forms during high temperature combustion of fuel
Nitrogen dioxide - NO2
Nitric oxide - NO
Nitrogen dioxide reacts with water to form Nitric Acid - HNO3
Nitric acid is a main component of acid rain
Sources:

Hydrocarbons
Compounds composed dominantly hydrogen, H and carbon, C
Methane, CH4 is a hydrocarbon
Benzene, formaldehyde and CFCs
Sources:
Many hydrocarbons are carcinogenic

Particles
Any solid or liquid particle
Sources:

Temperature Inversions

Inversions occur when the temperature of an air mass increases with increasing altitude.
Normally, warm pollution rises.
During an inversion, warm pollutants are unable to rise.
- quickly reaches the temperature of the surrounding air.

Pollution Domes and Plumes

Pollution domes develop around sources of pollution (city or industrial complexes) when there is a stable air mass (no wind) - the pollutants remain over the source forming a dome of pollution.
Pollution plumes develop when wind carries the pollutants away from the source area.

Global Dimming

Since 1950, solar radiation has decreased by 9 to 30% on various parts of the globe.
Caused by particle pollution:
1)
2)

Other Forms of Pollution

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2)
3)