Download Chapter 2 Earth as a System

CHAPTER 2 EARTH AS A SYSTEM
2.1 EARTH: A UNIQUE PLANET
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Only known planet that:
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Has liquid water on its surface.
Has an atmosphere that contains Oxygen gas
Supports life
Formed 4.6 billion years ago
Not a perfect circle. Oblate sphere. Pg 27
Equatorial Circumference 40,074 km
2.1 COMPOSITIONAL ZONES OF EARTH’S
INTERIOR
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Crust- the thin, solid, outermost zone of Earth.
Continental Crust- 15 to 80 km thick
 Oceanic Crust- 5-10 km thick
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Mantle- layer that underlies the crust.
Denser than the crust.
 2,900 km thick- makes up 2/3 of Earth’s mass
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Core- The center of Earth
Sphere shaped
 3,500 km thick
 Composed of Iron and Nickel
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2.1 STRUCTURAL ZONES OF EARTH’S
INTERIOR
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Lithosphere- The solid, outer layer of Earth that
consists of the crust and the rigid upper part of the
mantle. 15-300 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. 200-250 km thick.
Mesosphere- literally, the ‘middle sphere”’ the strong,
lower part of the mantle between the asthenosphere
and the outer core.
Outer Core-Dense liquid underneath the Mesosphere
2,900 km down
Inner Core- Dense, rigid solid. Center of the Earth.
5,150 km down.
2.1 EARTH AS A MAGNETIC
Earth has a North and South Pole
 Pg 29 Figure 3 Earth’s magnetic field extends
beyond the Earth’s Atmosphere and affects a
region of space called the magnetosphere.
 Source of Magnetic Field may be the liquid iron
in Earth’s outer core. Motions within the core
produce electric currents that in turn create
Earth’s magnetic field.
 Recent studies indicate that the sun and moon
also have magnetic fields. Research in this field
can help understand how we have our magnetic
field.
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2.1 EARTH’S GRAVITY
Gravity is the force of attraction that exists
between all matter in the universe.
 Newton’s Law of Gravitation states that, “the
force of attraction between any two objects
depends on the masses of the objects and the
distance between the objects”
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The larger and closer the objects are, the greater the
force of gravity is.
2.2 ENERGY IN THE EARTH SYSTEM
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System-An organized group of related object or
components that interact to create a whole
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They can be closed or open systems
2.2 ENERGY IN THE EARTH SYSTEM
Matter vs Energy
 Matter- Anything that has mass and takes up
space.
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Energy-the ability to do work
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Made of atoms and/or molecules
Transforms into heat, light, vibrations, or waves
Both can be transferred (or moved) into a system
or out of a system
2.1 SYSTEMS
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Closed System: A system in which energy, but
not matter is exchanged with the surroundings
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Open System: A system in which both energy and
matter can be exchanged with the surroundings.
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Pg 32 Closed Jar- Energy in the form of light and
heat can be exchanged through the sides. Because
the jar is closed no matter can be exchanged with a
closed container.
Open Jar, lake,
Earth is considered a system-A closed system
because matter exchange is limited.
FIRST LAW OF THERMODYNAMICS
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Law of Conservation of Matter:
States “Matter cannot be created or destroyed.”
 It instead, transforms or changes.
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Example: As a chemical breaks down from a reaction it
releases energy in the form of heat.
PG 33-35 OUTLINE NOTES
EARTH’S FOUR SYSTEMS
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The Atmosphere
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78% Nitrogen, 21% Oxygen, 1% other
The Hydrosphere
71% of earth covered in water
 Only 3% is fresh water
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The Geosphere
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Largest solid part of earth
The Biosphere
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Composed of all the forms of life/organic matter
EARTH’S ENERGY BUDGET
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First Law of Thermodynamics
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Conservation of energy and matter
Second Law of Thermodynamics
“When energy transfer takes place, matter becomes
less organized with time”
 Universe’s energy is spread out more and more
uniformly over time
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INTERNAL SOURCES OF ENERGY
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Pg 35 “The Earth’s interior was headed by
radioactive decay and gravitational contraction”
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What does this mean?
The Idea of convection
Warm things rise…..why???
 Why is it important….well this process drives the
plate motions in the surface layers of the geosphere
that create mountain ranges and ocean basins.
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EXTERNAL ENERGY SOURCES
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The Sun
Solar radiation warms Earth’s atmosphere and
surface
 Convection of air masses causes winds and ocean
currents
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Gravitational Energy
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From moon and sun cause tides/currents
CYCLES OF THE EARTH SYSTEM
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Nitrogen Cycle Pg 36
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Carbon Cycle Pg 37
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Builds protein that builds cells
Essential substances in the fuels used for life
processes.
Phosphorus Cycle Pg 37
Part of some molecules that organism need to build
cells
 Phosphorus was discovered from extracting it from
urine.
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Water Cycle Pg 38
2.3 ECOLOGY
ECOLOGY
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The study of the complex relationships between
living things and their nonliving, or abiotic
environment.
ECOSYSTEMS
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A community of organisms and the environment
that the organisms inhabit is called an
ecosystem.
As large as an ocean or as small as a rotting log.
 Largest ecosystem is the biosphere
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Energy flows through these ecosystems
producers, consumers, decomposers (food webs)
 Any examples?
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BALANCING FORCES IN ECOSYSTEMS
Organisms in an ecosystem use matter and
energy.
 Amounts of matter and energy are limited
 The largest population that an environment can
support at any given time is called the carrying
capacity.
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ENERGY TRANSFER
Starts with the Sun and photosynthesis
 Photosynthesis captures energy that then flows
through ecosystems from the plants, to the
animals that feed on the plants, and finally to the
decomposers of animals and plant remains.
 Food Webs Pg 41
 What is an Energy Pyramid? Let’s talk about
efficiently of a food web.
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CREATE YOUR OWN FOOD WEB
Create your own food web using the different
animals either in the movie “The Lion King”
 How does the song “The Cycle of Life” related to
this food web?
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