1. Earth as a System
Chapter 2

2. Standards
SES1e . Identify the transformations and major reservoirs that make up the rock cycle, hydrologic cycle, carbon cycle, and other important geochemical cycles.
SES6c. Explain how geological and ecological processes interact through time to cycle matter and energy, and how human activity alters the rates of these processes (e.g. fossil fuel formation and combustion)

3. Earth Basics
Section 1
Earth is the third planet from the sun in our solar system.
Earth formed about 4.6 billion years ago and is made mostly of rock.
Approximately 70% of Earth’s surface is covered by a thin layer of water known as the global ocean.
Earth is an oblate sphere, or a slightly flattened sphere.
Earth’s pole-to-pole circumference is 40,007 km. Its equatorial circumference is 40,074 km.
Earth’s average diameter is 12,756 km.

4. Oblate sphere

5. Earth’s Interior
Scientists have made important discoveries about Earth’s interior through studies of seismic waves.
Seismic waves are vibrations that travel through Earth and that are caused by earthquakes and by explosions near Earth’s surface.
By studying seismic waves as they travel through Earth, scientists have determined that Earth is made up of three major compositional zones and five major structural zones.

6. Compositional Zones of Earth’s Interior
crust the thin and solid outermost layer of Earth that lies above the mantle
Oceanic crust, which lies under the oceans, is only 5 to 10 km thick.
The continental crust varies in thickness from 15 km to 80 km.
mantle in Earth science, the layer of rock that lies between Earth’s crust and core
The mantle is nearly 2,900 km thick and makes up almost two-thirds of the planet.
core the central part of Earth that lies below the mantle
The center of Earth is a sphere composed mainly of nickel and iron whose radius is about 3,500 km.

7. Compositional Zones of Earth’s Interior, continued

8. Structural Zones of Earth’s Interior
The three compositional zones of Earth’s interior are divided into five structural zones.
lithosphere the solid, outer layer of Earth that consists of the crust and the rigid upper part of the mantle
The rigid lithosphere is between 15km and 300 km thick.
asthenosphere the solid, plastic layer of the mantle beneath the lithosphere; made of mantle rock that flows very slowly, which allows tectonic plates to move on top of it
The plastic asthenosphere is about 200 km thick.

9. Structural Zones of Earth’s Interior, continued
mesosphere literally, the “middle sphere”; the strong, lower part of the mantle between the asthenosphere and the outer core
The mesosphere reaches from the bottom of the asthenosphere to a depth of about 2,900 km.
Below the mesosphere is the liquid outer core.
The outer core surrounds the solid inner core, which begins at a depth of 5,150 km.

10. Earth’s Interior
The diagram below shows the layers of Earth’s interior.

11. Earth’s Gravity
Gravity is the force of attraction that exists between all matter in the universe.
Newton’s Law of Gravitation
Depends on the masses of the objects and the distance between them.The larger and closer together, the stronger the gravity between the objects will be.
Earth pulls objects toward the center of the planet (measured in Newtons (N).

12. Earth as a System Section 2
Earth system is a result of interaction between matter and energy.
Matter – anything having mass and volume. Made up of atoms
Energy – ability to do work. Can be transferred by heat, light, vibrations, or electromagnetic waves.
A system is described by the way that matter and energy are transferred within the system or to and from other systems.
Closed – energy and matter do not enter or leave
Open – energy and matter must be added or removed

13. Earth’s Four Spheres
Matter on Earth is in solid, liquid, and gaseous states. The Earth system is composed of four “spheres” that are storehouses of all of the planet’s matter.
The Atmosphere
a mixture of gases that surrounds a planet or moon
The atmosphere provides the air you breathe and shields Earth from the sun’s harmful radiation.

14. Earth’s Four Spheres, continued
The Hydrosphere
hydrosphere the portion of Earth that is water
Water covers 71% of Earth’s surface.
Water in the hydrosphere occur in the form of oceans, lakes, rivers, streams, glaciers and ice sheets, and groundwater.

15. Earth’s Four Spheres, continued
The Geosphere
geosphere the mostly solid, rocky part of Earth; extends from the center of the core to the surface of the crust
The geosphere includes all of the rock and soil on the surface of the continents and on the ocean floor.
The geosphere also includes the solid and molten interior of Earth.

16. Earth’s Four Spheres, continued
The Biosphere
biosphere the part of Earth where life exists; includes all of the living organisms on Earth
The biosphere is composed of all of the forms of life in the geosphere, in the hydrosphere, and in the atmosphere, as well as any organic matter that has not decomposed.
The biosphere extends from the deepest parts of the ocean to the atmosphere a few kilometers above Earth’s surface.

17. Earth’s Energy Budget
1st Law of Thermodynamics – energy cannot be created or destroyed, only transferred between systems.
Transfer of energy between Earth’s spheres are parts of the energy budget

18. Cycles in the Earth System
Reservoir is a place where matter or energy is stored
Cycle is a group of processes in which matter and energy repeatedly move through a series of reservoirs.

19. Nitrogen Cycle nitrogen in atmosphere animals denitrifying bacteria
ammonium
ammonification
decomposers
plant
nitrogen-fixing
bacteria in soil
bacteria in roots
nitrates
nitrites

20. Carbon Cycle

21. Water Cycle

22. Ecosystems of the Biosphere
Section 3
Ecosystems of the Biosphere
Ecology is the study of the complex relationships between living things and their nonliving, or abiotic environment.
ecosystem is a community of organisms and their abiotic environment
An ecosystem may be as large as an ocean or as small as a rotting log. The largest ecosystem is the entire biosphere.

23. Ecosystems, continued
Organisms that make their own food are called producers. Most producers use energy from the sun to produce their own food.
Consumers are organisms that get their energy by eating other organisms. Consumers may get energy by eating producers or by eating other consumers.
Some consumers get energy by breaking down dead organisms. These consumers are called decomposers.
To remain healthy, an ecosystem needs to have a balance of producers, consumers, and decomposers.

24. Balancing Forces in Ecosystems,
Energy Transfer
The ultimate source of energy for almost every ecosystem is the sun.
Producers, such as plants, capture solar energy by a chemical process called photosynthesis. This captured energy then flows through the ecosystem from the producers, to the consumers, and finally to the decomposers.
As matter and energy cycle through an ecosystem, chemical elements are combined and recombined. Each chemical change results in either the temporary storage of energy or the loss of energy.
The largest population that an environment can support at any given time is called the carrying capacity

25. Trophic Levels Energy moves from one trophic level to another Consumer
Producer
Sun

26. Energy Pyramid

27. Balancing Forces in Ecosystems, continued
Energy Transfer, continued
An energy pyramid is one way to see how energy is lost as it moves through the ecosystem.
Producers form the base of the pyramid. Consumers that eat the producers are the next level of the pyramid. Animals that eat those consumers form the upper levels of the pyramid.
As you move up the pyramid, more energy is lost at each level. Therefore, the least amount of energy is available to organisms at the top of the pyramid.

28. Balancing Forces in Ecosystems, continued
Food Chains and Food Webs
The sequence in which organisms consume other organisms can be represented by a food chain or by a food web.
food web a diagram that shows the feeding relationships among organisms in an ecosystem

29. Food Chain

30. Vocabulary Crust Atmosphere Mantle Hydrosphere Core Geosphere
Lithosphere
Asthenosphere
Mesosphere
System
Atmosphere
Hydrosphere
Geosphere
Biosphere
Ecosystem
Carrying capacity
Food web

31. Review A. the asthenosphere B. the lithosphere C. the mesosphere
1. The crust and the rigid upper part of the mantle are found in what part of the Earth?
A. the asthenosphere
B. the lithosphere
C. the mesosphere
D. the stratosphere

32. Review
1. The crust and the rigid upper part of the mantle are found in what part of the Earth?
A. the asthenosphere
B. the lithosphere
C. the mesosphere
D. the stratosphere

33. Review
2. How are scientists able to study the composition and size of the interior layers of Earth?
A. by direct observation
B. by analyzing surface rock samples
C. by using seismic waves
D. by deep-drilling into the interior layers

34. Review
2. How are scientists able to study the composition and size of the interior layers of Earth?
A. by direct observation
B. by analyzing surface rock samples
C. by using seismic waves
D. by deep-drilling into the interior layers

35. Review
3. Which of the following methods of internal energy transfer drives volcanic activity on Earth’s surface?
A. radioactive decay
B. convection
C. kinetic transfer
D. conduction

36. Review
3. Which of the following methods of internal energy transfer drives volcanic activity on Earth’s surface?
A. radioactive decay
B. convection
C. kinetic transfer
D. conduction

37. Review 4. Earth’s primary external energy source is
A. cosmic radiation.
B. the moon.
C. distant stars.
D. the sun.

38. Review 4. Earth’s primary external energy source is
A. cosmic radiation.
B. the moon.
C. distant stars.
D. the sun.

39. Review
5. What do decomposers break down to obtain energy?

40. Review 5. What do decomposers break down to obtain energy?
dead organisms

41. Review
6. What scientific principle states that energy can be transferred but that it cannot be created or destroyed?

42. Review
6. What scientific principle states that energy can be transferred but that it cannot be created or destroyed?
First Law of Thermodynamics

43. Review 7. Which layer of Earth’s interior does not transmit S waves?
A. layer B
B. layer C
C. layer D
D. layer E

44. Review 7. Which layer of Earth’s interior does not transmit S waves?
A. layer B
B. layer C
C. layer D
D. layer E