1. CHAPTER 3 LESSON 1
PLANET EARTH

2. 3.1 INFORMATION

5. A. WHAT IS EARTH?
Scientists divide Earth into four systems that all interact with each other.

6. ATMOSPHERE
Surrounding the planet is an invisible layer of gases, which is Earth’s outermost layer.

7. HYDROSPHERE
The liquid layer is made of Earth’s water, some of which is salty and some of which is fresh.

8. GEOSPHERE
Earth’s largest system is the solid material, which is made up of a thin layer of soil covering a large sphere of rock.

9. BIOSPHERE
The biosphere is Earth’s system containing all the living things on the planet.

10. BIOSPHERE
The biosphere has no clear boundaries because it is found within each of the other three systems of Earth.

12. ATMOSPHERE
A mixture of gases forms a layer around Earth.

13. ATMOSPHERE
The atmosphere is made up of 78% nitrogen, 21% oxygen, and 1% trace gases.

14. TRACE GASES

15. ATMOSPHERE
The atmosphere contains small amounts of solids, such as dust particles.

16. OTHER STUFF
DUST
WATER VAPOR
DUST

17. TRACE GASES 1. 2. 3.

19. ATMOSPHERE
The atmosphere has different layers, which vary in their temperature.

20. ATMOSPHERE
Atmosphere is divided into 5 layers.

22. ATMOSPHERE
The layers separate due to temperature and density.

23. ATMOSPHERE
The lighter layers rise to the top.

24. ATMOSPHERE
The heavier layers sink to the bottom.

25. EXOSPHERE
What does the prefix “exo” mean?

26. EXOSPHERE
Where would we expect to find the Exosphere? Why?

27. EXOSPHERE
The lowest density of gas molecules.

28. EXOSPHERE
Beyond the exosphere is outer space.

29. THERMOSPHERE
What does “thermo” mean?

30. THERMOSPHERE
What can we guess happens to the air temperature in this layer?

31. The air temperature increases.
THERMOSPHERE
The air temperature increases.

32. MESOSPHERE
What does “meso” mean?

33. MESOSPHERE
Where would we expect to find this layer?

34. MESOSPHERE
It’s the middle layer.

35. MESOSPHERE
The air temperature decreases.

36. STRATOSPHERE
Above the clouds … where the planes fly.

37. STRATOSPHERE
Gases do not swirl around.

38. Gases are stable and form flat layers.
STRATOSPHERE
Gases are stable and form flat layers.

39. STRATOSPHERE
Contains the ozone layer.

40. OZONE LAYER
The ozone layer protects Earth from the sun's harmful radiation.

41. TROPOSPHERE
Temperature decreases as you move away from Earth's surface.

42. TROPOSPHERE
Gases flow and swirl, causing weather.

43. This layer does not go very high, but is the heaviest layer.
TROPOSPHERE
This layer does not go very high, but is the heaviest layer.

44. What do you think makes this layer the heaviest?
TROPOSPHERE
What do you think makes this layer the heaviest?