Air and the Atmosphere
Air is a mixture of gases surrounding the Earth, forming the atmosphere, essential for breathing, weather, and protecting life on Earth.
Core concept
Air is mostly made up of nitrogen (about 78%) and oxygen (about 21%), with small amounts of other gases like carbon dioxide.
How it works
The atmosphere has different layers, with the troposphere (closest to Earth) being where weather occurs and we breathe.
Why it matters
The atmosphere protects us from harmful radiation from the Sun and helps regulate Earth's temperature.
Key detail
Air pollution, caused by factors like vehicle emissions and industrial waste, can harm the atmosphere and our health.
Exam highlight
Key diagram

Keywords worth remembering
Trending
Most searched
Quick revision
Study resources
Notes & downloads
Quick notes
• Air is mostly nitrogen (78%) and oxygen (21%).
• Small amounts of other gases exist too.
• The atmosphere has different layers.
• The troposphere is closest to Earth.
• Weather occurs in the troposphere.
• The atmosphere protects us from radiation.
• It helps regulate Earth's temperature.
• Air pollution can harm the atmosphere and health.