1. Earth as a System

2. What Is A System? The interaction between matter, energy, and life.
3 principles that apply:
Matter cycles
Energy Flows
Life Webs

3. Two Types of Systems Closed
Chemicals (matter) important to life move in cycles (Water cycle, CO2 cycle, Rock cycle)
Amount of matter stays the same-nothing added nor lost to the system.

4. Systems cont. Open Energy from sun enters system (Earth)
Heat energy flows out to space.
Energy is added and lost from the Earth.

5. Open or Closed Systems?

6. Past Perceptions of Earth
Studied as a collection of parts.
Was studied from the surface.

7. 20th Century Lead to New Understandings
Earth has interacting spheres, affect one-affect all.
Understanding came about because of environmental incidents. (ozone depletion, oil spills, cutting down the rain forest, etc.)
Technology allowed us to see Earth from a different perspective.
New perspective.

8. Technology
Computers & software allow for modeling and interpretation of data
GIS
Discovery
And to see Earth from a different celestial body

9. 4 Spheres of the Earth

10. Interaction of the Spheres
Earth

11. Atmosphere Gaseous envelope Mixture of Gases
Nitrogen, Oxygen, CO2, Argon, Water vapor.
Allows life (O2 CO2)
Protects from UV (O3)
Water vapor drives weather systems.
CO2 regulates temperature
Original atmosphere:CO2, H2O, S
90% of all gases in first 16 km of the atmosphere.

12. Geosphere Physical Features, (mountains, rocks, beaches, ocean floor)
7-70 km thick
Composition: Al, K, Ca, Fe, Mg, silicates
Density: g/cm3
Age: 4by-180my

13. Hydrosphere Oceans cover 71% of surface, 97% of all water.
Avg. depth 3,800 m.
3% is fresh water but 70% is frozen (CRYOSPHERE) and 20% is ground & surface water
½ of 1% is useable fresh water
Formed from degassing and comet impact
All water is recycled (closed system)

14. Biosphere
All living things of the planet; protozoa-fish- plants-people.
Interactions of the spheres allow for conditions to support life.
Human impact has changed & altered the other spheres.
Extremophiles

15. Extremophiles Thermophiles Halophiles Black Smokers
Morning Glory Pool, Yellowstone, MT
Great Salt Lake, UT
Juan De Fuca Ridge, Pacific Ocean

16. What Do You Know? What are Earth’s subsystems?
How do satellites help us understand the Earth as a system?
How does the Sun’s energy affect the oceans, atmosphere and life on Earth?
What is the role of the atmosphere and oceans on the average temperature of the Earth?
How is the Earth changing and what are the consequences for life on Earth?

17. THE END