1. Layers of the Atmosphere

2. The Composition of Air…….
Scientists began to analyze the air a little over 300 years ago.
A little bit of history:

3. Robert Boyle, Joseph Black, Daniel Rutherford
An English scientist named Robert Boyle discovered that air contains a substance needed for life when he noted that animals died without it. He called this substance OXYGEN! 100 years later a medieval student named joseph Black mixed limestone (a mineral) and acid together and that magically put out a flame. We call this CARBON DIOXIDE! About 15 years later a student of Black’s experimented with liquid to absorb air. This put out flames and killed living things. We now call this substance NITROGEN.

4. Composition of the Earth’s Atmosphere
Earth’s atmosphere is made up of nitrogen, oxygen, carbon dioxide, water vapor, and many other gases, as well as particles of liquids and solids.

5. What is the most abundant gas in the atmosphere?
The atmosphere is made up of solids, liquids and gases, mostly gases.
What are the most abundant gases? Nitrogen and oxygen
Why is oxygen important? It is essential to plants and animals; it is also involved in processes such as fire.

6. Stand outside and look up. What do you see
Stand outside and look up. What do you see? You might see blue sky or wooly clouds. At night you might see stars, a satellite or a crescent moon. What you are not seeing, however, is the complexity of our atmosphere. The atmosphere is a protective layer of gasses that shelters all life on Earth, keeping temperatures within a relatively small range and blocking out harmful rays of sunlight.

7. 2. stratosphere 3. mesosphere 4. thermosphere a. Ionosphere
The atmosphere has five different layers that are determined by the changes in temperature that happen with increasing altitude.
The atmosphere is divided into four layers:
1. Troposphere
2. stratosphere
3. mesosphere
4. thermosphere
a. Ionosphere
b. exosphere

8. TROPOSPHERE
Living at the surface of the Earth, we are usually only aware of the events happening in the lowest layer, the troposphere, where all weather occurs. The base of this layer is warmer than its top because the air is heated by the surface of the Earth, which absorbs the Sun’s energy

9. Stratosphere
Above the troposphere lies the stratosphere where jet airplanes fly. Temperatures increase with altitude because of increasing amounts of ozone. The ozone layer within the stratosphere absorbs harmful ultraviolet rays of sunlight.

10. Mesosphere
As the mesosphere extends upward above the stratosphere, temperatures decrease. The coldest parts of our atmosphere are located in this layer and can reach –90°C.

11. Thermosphere
In the forth layer from Earth’s surface, the thermosphere, the air is thin, meaning that there are far fewer air molecules. The thermosphere is very sensitive to solar activity and can heat up to 1,500°C or higher when the Sun is active making an aurora that lights up the night sky. Astronauts orbiting Earth in the space station or space shuttle spend their time in this layer.

12. EXOSPHERE
The upper layer of our atmosphere, where atoms and molecules escape into space, is called the exosphere.

15. Layers of the atmosphere
Time to draw a poster from page 57 in your science book!
Include the layers of the atmosphere:
TROPOSPHERE
STRATOSPHERE
MESOSPHERE
THERMOSPHERE
IONOSPHERE
EXOSPHERE
Make it colorful, add pictures to the different information you just learned about and write important information about the layer. Be neat, creative and have fun! Finish for homework 