1. Layers of the atmosphere

2. Layers of the atmosphere video
climate/earths-atmosphere.htm

3. Troposphere This layer extends from 0 km to 16 km.
The gases in this layer are nitrogen and oxygen
As altitude increases, temperature and density decreases.
All weather happens at this layer.
Air pressure is the highest at this layer.
This layer contains 99% of the earth’s water vapor.

4. stratosphere This layer extends from 16 km to 50 km.
The gases in this layer are nitrogen and oxygen.
As altitude increases, temperature increases and density decreases.
Jets cruise near the bottom of this layer.
The ozone layer is located here.
Weather balloons are flown to this layer.

5. Mesosphere This layer extends from 50 km to 90 km.
This layer is made up of nitrogen and oxygen.
As altitude increases, temperature and density decreases.
Meteors, or “shooting stars” burn up at this layer.
This is the coldest layer of the atmosphere.
This is the hardest layer to study since planes cannot fly high enough and satellites cannot fly low enough.

6. Thermosphere This layer extends from 90 km to 300 km.
The gases that make up this layer are nitrogen, oxygen, hydrogen and helium.
As altitude increases, temperature increases and density decreases.
Shimmering curtains of lights called auroras happen here.
This is the hottest layer of the atmosphere.
Space shuttles orbit at this layer.

7. ionosphere
Invisible layers of ions and electrons are found in the Earth's atmosphere. We call this region of atmosphere the ionosphere. The main source of these layers is the Sun's ultraviolet light which ionizes atoms and molecules in the Earth's upper atmosphere.
It is located at the top of the mesosphere and in the thermosphere.

8. exosphere This layer extends from 300 to more than 600 km.
This layer is made up of hydrogen and helium.
As altitude increases, temperature increases and density decreases.
Many satellites orbit at this layer.
Air pressure is the lowest at this layer.
It is sometimes considered part of outer space.