The Atmosphere

1
The Atmosphere

• Notes blue

2
Atmosphere

• The atmosphere is a mixture of gases that
  surround the Earth.
• It is made of
• 78 Nitrogen
• 21 Oxygen
• 1 Argon, Carbon Dioxide, water vapor, and other
  gases.

3
Altitude and Air Pressure

• Have you ever felt your ears pop when you fly? Or
  when you drive up a mountain?
• This is due to air pressure.
• Air pressure is a measure of the force of air
  molecules pushing on the surface of the Earth.

4
Air Pressure

• Think of it like this pyramid
• The people at the bottom have a lot more weight
  on them (pressure or force) than the people at
  the top!

5
Air pressure

• Its the same in our atmosphere. As you increase
  your altitude, or the vertical distance above the
  surface of the Earth, the fewer air particles
  push down on you.
• So, as altitude increases, air pressure decreases.

6
Layers of the Atmosphere

• Troposphere- the lowest layer next to the surface
  of the Earth.
• Stratosphere- This layer contains ozone in the
  ozone layer.

7
Ozone?

• Ozone is a molecule that is made up of three
  oxygen molecules instead of the normal two oxygen
  molecules.
• The ozone layer absorbs solar energy (UV
  radiation) which warms the air and protects life
  on Earth.

8
Layers of the Atmosphere

• Mesosphere- The coldest layer which also contains
  large wind storms.
• Thermosphere- The uppermost layer which has the
  hottest temperature (reaching 1,700C) but does
  not feel hot.

9
Layers of the Atmosphere

• Special layer The Ionosphere
• The ionosphere is an area in the upper
  mesosphere and lower thermosphere where nitrogen
  and oxygen atoms absorb solar energy. These
  particles become charged and result in light
  patterns, known as Aurora borealis and Aurora
  australis