Transcript The Greenhouse effect

Energy in the Earth System
Big Ideas
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The climate system (and life on Earth ) is maintained by
energy coming from the Sun (electromagnetic
radiation).
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The atmosphere, which surrounds us, affects us in
many ways, including the Greenhouse effect.
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Short wave radiation (light) is absorbed by matter and
change to long wave radiation (heat).
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The balance between incoming light energy and
outgoing (emitted) heat determines temperature of the
planet.
The Greenhouse effect
Our important Atmosphere
Adapted from the Environmental Literacy Council Environmental Science Teacher Exchange
http://www.enviroliteracy.org/category.php?id=13
The role of an atmosphere
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Sunlight on the Moon
215º F day time
-243º F night time
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Sunlight on the Earth
134º F
Death Valley, July 10, 1913
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-129º F
Antarctica, July 21, 1983
With no atmosphere the Earth’s ave. temperature would be -27 º
Earth’s Atmosphere
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Is capable of quickly moving
and distributing mass and
heat over large distances.
Is an efficient communicator
Directly affects life on Earth
by supplying the gases for
the respiration of
vegetation and animals.
And by moving water from
oceans to land.
Structure of the Atmosphere
As you go up..
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Chemical composition
changes.
Temperature changes
Pressure changes
90% of mass is in first
40 km!
Composition of the Atmosphere
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Nitrogen
78.1%
Oxygen
20.9%
Water vapor 0 to 4%
Argon
0.9%
Neon
0.002%
Carbon Dioxide 0.035%
Methane
0.0002%
Helium
0.0005%
Krypton
0.0001%
Nitrous oxide 0.00003%
Hydrogen
0.00005%
Ozone
0.000004%
The energy that drives the climate system
comes from the Sun
The Sun …
Is the star located at the center of our
planetary system.
 Is composed mainly of hydrogen and
helium.
 Sends solar heat energy which travels
through space in the form of
electromagnetic waves.
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At the top of the atmosphere
the Energy is fairly constant
The Solar
Constant
1,370 Watts/m2
Energy interacts with matter
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Reflection
(albedo)
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Transmission
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Absorption
(becomes heat)
What happens to solar radiation once it
meets the Earth's atmosphere?
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Energy is mainly
transmitted through
the atmosphere
30% is reflected,
mainly from clouds
Energy is absorbed
by the land and
water.
Albedo: how well an
object reflect energy.
Earth’s Energy Budget
Incoming energy= Outgoing energy
The Sun and Earth give off Energy
Earth’s Energy Budget in detail
The Greenhouse Effect
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Short wave and visible
pass easily through the
atmosphere and are
absorbed by the Earth’s
surface.
Some energy is radiated
back into the atmosphere
where it is absorbed by
molecules of gas.
The heated gases
radiate energy in all
directions, including back
to Earth.
The Greenhouse gases
Carbon Dioxide
 Methane
 Nitrous oxide
 Water vapor
 CFC’s
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Greenhouse gases
Greenhouse
Gas
How much it
contributes
Source
methane
18%
Wetlands, Cattle
burning, Natural gas
Oceans, lakes
Carbon dioxide
49%
Burning wood & fuel
Respiration
Deforestation
Nitrous oxide
6%
Chlorofluorocarbons
(CFC’s)
14%
Car exhaust
fertilizers
Refrigerants, Solvents
Foamed plastic
The Climate System
Big Ideas
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The climate system (and life on Earth ) is
maintained by energy coming from the Sun
(electromagnetic radiation).
The atmosphere, which surrounds us, affects us
in a way called the Greenhouse effect.
Short wave radiation (Light) is absorbed by
matter and change to long wave radiation
(heat).
The balance between incoming light energy and
outgoing (emitted) heat determines temperature
of the planet.
A good question….
Why does light energy from the Sun
pass through the greenhouse gases
unabsorbed,
but the infrared energy
radiated from the Earth
gets absorbed?
Answer: Resonance: