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Air and atmosphere
Atmosphere protects us
The Earth's atmosphere has played and still plays a vital role in protecting life on Earth.
- The Earth's atmosphere protects us from meteorites:
Meteorites are blocks of ice and rock that come from space where they move at high speeds.
On entering the atmosphere they undergo very important frictions that raise their temperature and eventually make them explode.
However some large meteorites can reach the ground and cause damage depending on their size of their speed.
- The ozone layer protects us from harmful radiation:
Located in the stratosphere this layer of only 3 mm thick stops most of ultraviolet radiations (UV) that could be harmful for humans and all other living organisms.
- The Earth's atmosphere maintains an ideal temperature for life.
Without this atmosphere the temperatures would be extreme: from one hundred degrees Celsius above zero during the day, to one hundred degrees Celsius below zero at night. The atmosphere reduces the temperature fluctuations.
The atmosphere also allows us to benefit from higher temperatures through the greenhouse effect. Without it the temperatures on Earth would be too low: It can trap some of the heat received from the Sun. Instead of being returned and lost in space this heat is kept in the atmosphere.
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