Question

Describe the four zones of atmosphere and their significance in detail. Explain the types 

and sources of air pollution.

Answer 1

The four zones are

• troposphere (provides oxygen and serves as a thermal insulator),
• stratosphere (provides ozone that protects us from harsh UV radiation),
• mesosphere (protects us from meteors)
• thermosphere (protects us from x-rays and UV-radiation coming from the Sun).

Main sources of pollution:

• internal combustion engines (cars, planes)
• burning coal and fossil fuels
• cows
• smoke from factories
• chlorofluorocarbons (CFCs) and halons from refrigerators and aerosols.