1. Chapter 3 Environmental Science 2017-18
Dynamic Earth
Chapter 3
Environmental Science

2. Section 1: The Geosphere
Objective 1: Describe the composition and structure of the Earth.
Objective 2: Describe Earth’s tectonic plates.
Objective 3: Explain the main cause of earthquakes and their effects.
Objective 4: Identify the relationship between volcanic eruptions and climate change.
Objective 5: Describe how wind and water alter Earth’s surface.

3. Section 1: The Geosphere (continued)
The GEOSPHERE is non-living and contains all of Earth’s rocks, soils, and minerals.
Most is located in Earth’s interior!
5 layers:
Lithosphere
Asthenosphere
Mesosphere
Outer Core
Inner Core

4. Section 1: The Geosphere (continued)

5. Section 1: The Geosphere (continued)
The LITHOSPHERE
The OUTER layer
Cool and rigid
Includes the crust and the top part of the mantle
Divided into pieces called tectonic plates
km thick
The ASTHENOSPHERE
The SOFT layer BELOW the lithosphere
Has soft rock that flows
Allows tectonic plates to move above it
Part of the mantle
250 km thick

6. Section 1: The Geosphere (continued)
The MESOSPHERE
Lower part of the mantle
2,550 km thick
Made of dense, iron-rich minerals
the OUTER CORE
2,200 km thick
The outer shell of the core
Made of LIQUID nickel and iron
The INNER CORE
1,228 km thick
SOLID nickel and iron
At the center of the Earth
Between 4,000 and 5,400 degrees Celsius

7. Section 1: The Geosphere (continued)
TECTONIC PLATES
Large chunks of the Lithosphere
May move away from, collide with, or slip past each other
TP movement causes mountains, volcanoes, earthquakes, and other natural phenomena
WHERE ARE THE TP BOUNDARIES? WHY DOES IT MATTER?
EARTHQUAKES
Caused by slippage of tectonic plates along a “FAULT” which is a break in the crust
TPs move all the time (we can’t feel them) but earthquakes are caused by large movements.
WHERE DO EARTHQUAKES OCCUR?

9. Section 1: The Geosphere (continued)
VOLCANOES
A mountain built when magma (melted rock) rises from the interior to Earth’s surface
Magma is called lava once it reaches the surface
Can occur on land or under water
THIS IS HOW ISLANDS ARE FORMED!
Volcanoes explode when pressure builds up inside of them, but some flow all the time (never building up pressure)
EFFECTS
Clouds of ash and sulfur-rich gases go into the atmosphere
Reduced sunlight
Change in global temperature

10. Section 1: The Geosphere (continued)
WEATHERING AND EROSION
Weathering: process of rocks breaking down due to chemical reactions
Erosion: process of Earth’s surface being loosened, dissolved or worn away and moved by a natural agent such as wind, water, ice or gravity
Both can make DRAMATIC changes
to the Earth’s surface!

11. Section 2: The Atmosphere
Objective 1: Describe the composition of Earth’s atmosphere.
Objective 2: Describe the layers of Earth’s atmosphere.
Objective 3: Explain three mechanisms of heat transfer in Earth’s atmosphere.
Objective 4: Explain the greenhouse effect.

12. Section 2: The Atmosphere (continued)
COMPOSITION OF THE ATMOSPHERE
78% Nitrogen
21% Oxygen
1% Other gases
Atmospheric dust (tiny solid particles)
Soil, salt, ash, volcanic ash, skin, hair, pollen,
bacteria, viruses, aerosols, etc
AIP PRESSURE
Atmosphere is pulled to Earth’s surface by gravity
Therefore, the atmosphere is more dense at the surface
WHAT HAPPENS TO THE AIR AS YOU CLIMB
MOUNTAINS? WHY?

13. Section 2: The Atmosphere (continued)
LAYERS OF THE ATMOSPHERE (starting closest to Earth’s surface)
Troposphere (0-18 km from Earth)
Weather happens here
Densest layer
Highest air pressure and jet stream
Most greenhouse gases here
Interaction with all of Earth’s living things
Stratosphere (18-50 km)
Ozone (O3) layer is in this layer
Temp increases as altitude increases
Reduces harmful radiation
O3 absorbs UV rays and warms the air

14. Section 2: The Atmosphere (continued)
Mesosphere (50-80 km)
“Middle Sphere”
Coldest layer
Where most meteors burn up
Thermosphere ( km)
Farthest from Earth’s surface
HIGH temps above 2,000 degrees C
Due to N2 and O2
Very THIN layer. You wouldn’t feel the HEAT!!!
Where satellites orbit
Where the aurora borealis happens

15. Section 2: The Atmosphere (continued)
ENERGY IN THE ATMOSPHERE
RADIATION- transfer of energy as
electromagnetic waves
From the sun and fire
CONVECTION- transfer of energy
when variations in temp move air matter
Liquids and gases
CONDUCTION- transfer of energy from
a warm object to a cold object by touching
Solid to solid
Direct contact

16. Section 2: The Atmosphere (continued)
GREENHOUSE EFFECT
Sunlight comes from the sun and warms the Earth
Greenhouse gases absorb and reradiate infrared radiation near Earth
Without it, Earth would be too cold to live on
GREENHOUSE GASES
Water vapor
CO2
Methane
Nitrous oxide
Amounts vary due to natural and industrial processes
Some scientists say these gases and cause climate change

18. Section 3: The Hydrosphere and Biosphere
Objective 1: Name the three major processes in the water cycle
Objective 2: Describe the properties of ocean water.
Objective 3: Describe the two types of ocean currents.
Objective 4: Explain how the oceans regulate Earth’s temperature.
Objective 5: Discuss the factors that confine life to the biosphere.
Objective 6: Explain the difference between open and closed systems.

19. Section 3: The Hydrosphere and Biosphere (continued)
THE WATER CYCLE
Evaporation- liquid water is heated and rises into the atmosphere as a vapor
Condensation- water vapor forms droplets on dust particles to make clouds
Precipitation- condensed water droplets fall from the clouds as rain, snow, sleet or hail

20. Section 3: The Hydrosphere and Biosphere (continued)
ASSIGNMENT TIME!
It’s time for you and your group members to create your own, unique, non-plagiarized WATER CYCLE SONG!
2-4 minute video
MUST be at least 2 minutes to earn a passing grade! Shoot for 4 minutes!
Props and costumes MUST be incorporated into your video
Can video it with your cell phone
Submit by ing it to
If you opt, you may present it to the class live instead of videoing it.

21. Section 3: The Hydrosphere and Biosphere (continued)
OCEANS
All of the Earth’s oceans together make up the WORLD OCEAN
Pacific Ocean is the largest and deepest ocean on Earth
Atlantic Ocean is the 2nd largest, but is ½ the size of the Pacific Ocean
Indian Ocean is the third largest
Southern Ocean (designated in 2000) surrounds Antarctica- rapid water movement
Arctic Ocean is the smallest- most of its surface is floating ice called pack ice

22. Section 3: The Hydrosphere and Biosphere (continued)
OCEAN WATER
Contains more salts than freshwater
Salts dissolved out of rocks on land and were carried down rivers over the years
Salts deposited from underwater volcanoes
SALINITY- salt concentration
TEMPERATURE ZONES
Ocean water changes temperatures as you go deeper
Warm water on surface (surface zone) and cold water on ocean floor (dark, deep zone)
The THERMOCLINE is the zone where temperatures fall RAPIDLY with depth
A TEMPERATURE REGULATOR
Ocean water absorbs sunlight and stores it to maintain a stable temperature
Specific heat of water

23. Section 3: The Hydrosphere and Biosphere (continued)
OCEAN CURRENTS
SURFACE CURRENTS- stream- like movements of water at or near the surface of the ocean
Driven by wind patterns
Warm or cold water currents (but these don’t mix well)
Ours is called the Gulf Stream
DEEP CURRENTS- flow along the ocean floor

24. Section 3: The Hydrosphere and Biosphere (continued)
FRESHWATER
3% of Earth’s water
Most is locked up in ice caps and glaciers
RIVERS
A network of streams that drains an area of land
Tributaries flow into larger streams and rivers
Mississippi River system covers about 40% of the US
GROUNDWATER
Water that sinks into the ground
Fulfills the water needs of humans
Less than 1% of water on Earth
AQUIFERS
A rock layer that stores and allows the flow of ground water

25. Section 3: The Hydrosphere and Biosphere (continued)
ENERGY FLOW IN THE BIOSPHERE
The sliver of the Earth that can support life
Why?
Liquid water
Moderate temperatures
A source of energy
Meets needs of organisms
Materials organisms need must continually be cycled
Almost every organism gets its food from plants and algae
Plants make their food via sunlight
CLOSED VS OPEN SYSTEM
CLOSED- energy enters and leaves but matter does not
EX: Earth, a watch
Food chain
Carbon cycle
Water cycle
OPEN- both matter and energy are exchanged b/t system and surroundings
EX: human body, Lake Jordan