Atmospheric Pollution

Layers of the Atmosphere

The atmosphere is not uniform — it is arranged as concentric layers of differing density and composition.

• Troposphere — the lowest layer, extending up to about 10 km above sea level. This is where humans and other living organisms exist. It is turbulent and dusty, rich in water vapour and clouds, and is the site of strong air movement and weather.
• Stratosphere — lies above the troposphere, roughly between 10 km and 50 km. It contains dinitrogen, dioxygen, ozone, and only a little water vapour.

The Two Zones of Atmospheric Pollution

Because the troposphere and stratosphere behave so differently, atmospheric pollution is studied as two separate problems:

1. Tropospheric pollution — pollutants building up in the breathable air near the ground.
2. Stratospheric pollution — chemical damage to the protective ozone layer far above us.

Why the Ozone Layer Matters …