1. Chapter 2 - Earth as a System

2. The Earth’s Shape Earth appears to be a sphere.
Rotation causes flattening- called an oblate sphere
1. Centripetal Force –the force required
to hold an object in a circular path a. Polar regions flatten b. Equatorial zone bulges

3. Gravity -the force of attraction that exists between all matter
Newton’s Law of Gravitation
the force of the attraction between two objects depends on the masses of the objects. The more mass, the greater the attraction
The force of attraction decreases as the distance between the objects increases (see figure 4, page 30)
The force of gravity is measured in Newtons

4. Earth as a Magnet Earth can be thought of as a dipole (2-pole) magnet.
Earth's magnetic field lines are not as symmetrical as those of the bar magnet. The impact of the solar wind causes the lines facing sunward to compress, while the field lines facing away from the Sun stream back to form Earth's magneto tail.
We call this magnetic field surrounding Earth the “magnetosphere”

5. Earth’s Layers
Crust-
Feldspars
Mantle-
Magnesium Iron Silicates
Compositional Zones are based on the chemical makeup of each layer. These three zones are the layers of the Earth that you learned about in Elementary and Middle School.
Core-
Nickel and Iron

6. Earth’s Layers
Lithosphere-
SOLID
Structural Zones are based on the state of the matter in each layer. Knowing whether a layer is molten or solid rock can help scientists understand and better predict the behavior of the crust’s movements
Asthenosphere-
PLASTIC
Mesosphere-
SOLID
Outer Core-
LIQUID
Inner Core-
SOLID

7. Define Compositional Zones:
Crust
Two types:
Continental Crust: Km thick
Oceanic Crust: 5-10 km thick
Made of feldspars
Mantle
2900 km thick
Composed of magnesium iron silicates
Core
3500 km thick
Composed of Iron and Nickel

8. Define Structural Zones:
Lithosphere
km thick
Solid and Brittle
Asthenosphere
km thick
Plastic, flows
Mesosphere
2400 km thick
Solid
Outer core
Generates earth Magnetic field
2200 km thick
Liquid
Inner Core
2050 km thick

9. Ch 2-2: Systems
Systems- an organized group of related objects or components that interact
all systems have boundaries
many systems have energy and matter that flow through them
closed system- a system in which energy, but not matter is exchanged
open system- a system in which energy and matter are exchanged
Earth’s system- open, but very limited exchange of matter
Meteors
manmade space probes
Open System
Closed System

11. Earth’s Energy budget
Energy exchange on Earth is predictable following scientific laws
1st law of thermodynamics-energy cannot be created or destroyed
2nd law of thermodynamics- when energy is transferred, matter becomes more disorganized (entropy)

12. Sources of energy on Earth
External Sources
Solar radiation (heating)- most important source of energy that drives all systems on earth
bio- fuels plant growth
hydro- drives ocean currents
geo- breaks down rocks either though direct heating or erosion
atmos- drives winds through uneven heating of Earth’s surface
Sun/Moon’s gravity create tides and ocean mixing

13. Internal energy sources
Earth’s interior heated by radioactive decay
Earth’s surface is cooler that interior causing hot materials to rise
provides limited energy for limited life forms
drives motion of tectonic plates

14. Chapter 2-3
Ecology- is the study of the relationship between living (biotic) and non-living (abiotic) things
Ecosystems- a community of organisms and their abiotic (non-living) environment
Producers: organisms which make their own food
Consumers: Organisms which consume other organisms to get their energy
Decomposers: organisms that break down decaying material for food

15. Ecological Balance
Carrying Capacity- the largest population an environment can support at any given time
Responses to change
Ecosystems can recover from short term changes
Ecosystems have difficulty recovering from long term changes

16. Energy Transfer
Ultimate source of energy is SUN
As matter cycles through the ecosystem, energy is lost through chemical reactions
least amount of energy is available to consumers at the top of the food chain

17. Make a food chain from the food web below: