Download Unit 1 Chapter 2 Notes

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Chapter 2 Earth as a System
Section 1 Earth: a Unique Planet
Prove to me that the earth is round.
Evidence of spherical earth:
1.
Tops (masts) of ships are the first part to appear above the
horizon.
2.
Sailors noticed changes in the night time sky as they sailed north
or south.
Sailing north, the North Star rises until the North Pole.
3.
Lunar eclipses show the earth's shadow as a circle or an arc of a
circle. Lunar Eclipse - the earth blocks the sun light that normally
is reflected from the moon.
Important Person who helped measure the circumference was:
_____________________________
Greek astronomer from ~ 2000 years ago determined the
circumference of the round earth. He used two wells, the angle of
the sun's shadow and the distance between the two wells to
determine the circumference.
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Eratosthenes was within 15% of the correct answer. He made two
mistakes
1.
The wells were not dug straight down
2.
Seine and Alexandria are not directly north and south of each
other.
Earth Basics
The earth is 3rd rock from the sun. She was formed over 4.6 billion
years ago. Approximately 71% is covered in water, hence the nickname
"The Blue Planet".
It is not a true sphere. We are called an OBLATE SPHEROID or better
yet, SPHEROIDAL. We have two different measurements for the
circumferences.
Earth's Circumference:
Equatorial _____________
Polar__________________.
Earth's Diameter:
Equator
________kms (_________ miles)
Poles
________kms (___________ miles)
.
3% difference
Earth's Interior
The Layers of the Earth: Science Reference Tables :OSA:NYSED
___________- Lithosphere
________% of Earth's mass
thickness and depth varies
under oceans __________ km
under continents ________ km
All drilling and mining is done in this layer - we have never
gone deeper than the crust.
Made up of lighter rocks and minerals.
Temperature increases with depth until it reaches approx
1000o C
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-
Below 70 meters the temperature starts to increase 1o C for
every 40 meters of depth. The rate slows down after
several kilometers so that the center of the earth is
approximately 6000 – 7000o C.
__________________ thin slush like layer between the crust and mantle
this is where the action is
____________ (Mohorovici discontinuity)
_________________ Approximately ____________ mass of the Earth's mass
Approximately 2900 km thick
temp is between 1500 – 3200 o C
temp increases with depth
solid with liquid properties
made up of heavy metals:
_________________
_________________
_________________
_____________ -depth is approximately 3000 – 5000 km
- temp is between 5000 – 6000o C
- temp increases with depth
- made up of liquid like metals:
_______________
_______________
______________ depth is approx 5000 – 6000 km
- temp is approx 6500o C plus
made up of solid:
_________________
_________________
Why does the temperature increase in the crust?
1.
____________________________________________________________
2.
____________________________________________________________
___________________________________________________________.
3.
___________________________________________________________.
4.
___________________________________________________________.
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Earth as a magnet:
The magnetic field in the Earth is like having a bar magnetic
inside a ball. The positive end is the north (we use a compass to
prove this) and the negative end is the South Pole.
True North which is where North and South Pole are, magnetic
north is about _____ o different. This becomes evident when you
look on maps; you will see two arrows to point to either magnetic
north or true north.
Our magnetic field helps protect ______________________
_______________________________________________.
Earth's Gravity:
______________ is the measure of the strength of the pull of
gravity on an object. Measured in Newton. Can change
depending on where you are.
____________ is how much stuff is in side of an object. It
depends on volume. Does not change depending where you are.
Where do we weigh more? At the North Pole or the Equator
Why?
_____________________ – because you are closer to the
middle of the earth and gravity has more pull on you. Gravity is
the force that holds us together and holds us on the earth. As
the earth spins, the gravity pulls us closer to the center of the
earth, which is the center of gravity. The difference is about
____________% less!
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Section 2 Energy in the Earth System
__________________:
A group of objects that interact with each other to create
something whole. The system may seem to work alone, however,
most systems are linked to one another. Uses Matter and Energy
_______________ - anything that has mass and takes up space.
_______________ - the ability to do work. Can be heat, light,
vibrations, even electromagnetic waves.
There are two types of systems (ok maybe a third that I made
up).
___________ – an Island
An___________ is a state of a system, in which a system continuously interacts with its
environment. A free transfer of energy or matter.
___________ – a biodome
A___________________is a system in the state of being isolated from the environment.
It is often used to refer to a theoretical scenario where perfect closure is an assumption,
however in practice no system can be completely closed; there are only varying degrees
of closure. A limited exchange of energy and matter.
Quasi - Earth.
The exchange or transfer of energy or matter is limited.
Earth's Four Spheres
Using these systems we can learn a great deal. There are 4 main
systems (spheres) that we study.
1. __________________-_____________________________
2. __________________- _____________________________
3. __________________-_____________________________
4. __________________-_____________________________l
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http://www.classzone.com/books/earth_science/terc/content/visualiza
tions/es0102/es0102page01.cfm?chapter_no=visualization
Our interactions between all of the “spheres” make us very
DYNAMIC. Some of the interactions are small and minor, some are
quick and massive while others cover such a large scale that they
take so long we don’t notice.
Dynamic – what is it??????
It means ever changing and interacting. Sometimes interactions
occur on a one time basis, and some occur on a regular basis. We
call these “cycles” or “cyclic”. The ones that make us dynamic are
water, carbon, nitrogen and phosphorus and energy.
Even though we are Dynamic, we are also balanced – matter can
neither be created nor destroyed so we maintain a balance called
DYNAMIC EQUALIBRIUM. This simply means that for every action,
there is an equal reaction. For every mountain that erodes, one is
created by volcano. For every rain drop that falls, more is
evaporated. And so on.
Earth's Energy Budget
Energy exists in many forms, such as heat, light, chemical energy, and
electrical energy. Energy is the ability to bring about change or to do work.
Thermodynamics is the study of energy.
Two types of Energy
_____________________________:
Geothermal - ____________________________________
1.
2.
3.
4.
Compression
Radioactive decay – Uranium and Potassium gives off heat
energy with the crust.
There may be still some heat left over from the earth’s
formation.
Friction from movement of and in the crust.
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____________________________:
This is really not like a cycle at all but a budget or a balance sheet. The
amount of energy coming into a system should always equal the amount of
energy going out. That is why it is also called the Earth’s Energy Budget.
Some of the energy is directly used like the solar, tidal and geothermal. And some
is stored for later usage like fossil fuels, water, ice, live plants and some
sedimentary rocks.
Unlike the other cycles – a little energy is lost and never retrieved. This
is called the physics of the Law of Thermodynamics.
Law I
____________________________________________________
___________________________________________________
Law II
_____________________________________________________
_____________________________________________________
____________________________________________________
Potential energy, as the name implies, is energy that has not yet been used, thus
the term potential. Kinetic energy is energy in use (or motion). A tank of
gasoline has a certain potential energy that is converted into kinetic energy by
the engine. When the potential is used up, you're outta gas!
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Humans and insects and other live creatures also have an effect the interactions of
the cycles and systems that occur on Earth. It causes the ripple effect. When
someone does something in one area, it triggers a chain reaction elsewhere. Like
the butterfly that flaps its wings in Africa that produces a Hurricane on Long Island.
The Cycles In the Earth:
_____________________________________
_____________________ is a gas. Our atmosphere is approximately____%
nitrogen. We cannot use this for life. In order to use it, it must go though some
changes,
called fixing. It means it changes it from the air version to the
compounds we can use though a chemical process.
A. Air to soil through nitrogen fixing
B. Soil to plant and animal (plants use it to grow - animal eats
plants)
C. Back to air though decay
D. Repeat
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______________________________________
Even though we feel that carbon can be dangerous (carbon
monoxide, etc), it is essential for life. It is the building block for all
organic materials and organism. We are carbon based life forms,
just ask any alien.
A.
B.
C.
________ enters the atmosphere as a by-product (bad
breath, fluctuant, composts, volcanoes, etc.)
_________ is removed from the atmosphere by:
a. Plants for photosynthesis
b. Phytoplankton uses it for photosynthesis and when they
die they release it into the water that releases it.
_______ is diffused out of the oceans (diffuse means to
move from high concentrations to low and since the air is
lower than the water it is released into the air)
Carbon is never _______________– just rearranged from one form to another.
Sometimes it is a quick change like a decomposing apple and then it
sometimes takes a very long time like a plant decaying, being buried and
squished then later burned as coal.
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________________________________
_____________ moves through every sphere except the atmosphere
because it is rarely a _____.
A. It gets to the soil from rocks breaking down and being
dissolved in water, or when an animal dies.
B. Plants absorb it and it becomes part of them
C. Animals eat the plant, and both die, returning it to the
ground.
_____________________
___% of water is in oceans - salt water
___ % of water is frozen - glaciers
___ % of water is fresh drinking
streams - very little
rivers – very little
lakes – a little more
swamps – a little more
UNDERGROUND- majority of drinking water
Water Cycle Terms
______________ - water vapor going into the atmosphere
- usually by the sun, directly or indirectly
_______________ - water gas (H2Og) changing to Water Liquid (H2Ol)
- must have condensation nuclei (dust) to form clouds
______________- gravity pulling water from the clouds- moisture
source for local water budget.
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___________ - process by which green plants lose water through their
leaves
___________________- evaporation & transpiration combined
- the way most water enters the air
Section 3 - ___________________________
_____________________
A community of organism and the abiotic (non living)
environment they inhabit.
________________________________________
Small changes in any part of the environment can affect the
ecosystem, however, the system usually has the ability to maintain
and restore itself.
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When the change is a large one, like a fire or a flood, the ecosystem
can be disrupted for some time. Eventually it will go back to its
normal state.
__________________________________
The sun is the ultimate source of energy. The energy is cycled
through the various cycles and it all works together.
_______________________________________
All Earth's systems are interconnected. A change in one system can
effect another system.
By helping preserve the environment and not treating Mother Earth
poorly we become stewards of the planet. We become responsible
for Mother Earth and her wellbeing. In other words, don't hurt Mother
Nature.