CHAPTER 3 LESSON 1 PLANET EARTH

3.1 INFORMATION

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

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

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

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.

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

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

ATMOSPHERE A mixture of gases forms a layer around Earth.

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

TRACE GASES

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

OTHER STUFF DUST WATER VAPOR DUST

TRACE GASES 1. 2. 3.

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

ATMOSPHERE Atmosphere is divided into 5 layers.

ATMOSPHERE The layers separate due to temperature and density.

ATMOSPHERE The lighter layers rise to the top.

ATMOSPHERE The heavier layers sink to the bottom.

EXOSPHERE What does the prefix “exo” mean?

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

EXOSPHERE The lowest density of gas molecules.

EXOSPHERE Beyond the exosphere is outer space.

THERMOSPHERE What does “thermo” mean?

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

The air temperature increases. THERMOSPHERE The air temperature increases.

MESOSPHERE What does “meso” mean?

MESOSPHERE Where would we expect to find this layer?

MESOSPHERE It’s the middle layer.

MESOSPHERE The air temperature decreases.

STRATOSPHERE Above the clouds … where the planes fly.

STRATOSPHERE Gases do not swirl around.

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

STRATOSPHERE Contains the ozone layer.

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

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

TROPOSPHERE Gases flow and swirl, causing weather.

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.

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