The Greenhouse Effect and Global Warming
The greenhouse effect is a natural part of how
our world works.
Without the greenhouse effect,
our planet would be MUCH colder than it is and
would be in a state of permanent ice age.
The steps for the greenhouse effect are:
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Incoming solar radiation warms the surface of
the earth and oceans.
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The warmed surfaces re-emit radiation in the
infrared portion of the electromagnetic
spectrum.
Infrared radiation should be
thought of as heat radiation (invisible).
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Infrared radiation carries heat away from the
warmed earth and oceans (could escape back
into space).
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Gases in the earth atmosphere reflect
escaping infrared radiation back to earth
which “re-warms” the earth and oceans.
The amount of reflection in the last step is the
greenhouse effect.
If the amount of reflection
changes, the greenhouse effect will increase or
decrease.
Common Green House Gases are:
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water vapour (H2O)
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responsible for 70% of green house effect
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largest contribution to the natural
greenhouse effect
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carbon dioxide (CO2)
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methane (CH4)
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nitrous oxide (NO2)
Natural Gas
Global Warming is the result of an increase in
greenhouse gases.
Of particular concern is the
level of carbon dioxide.
Increases in this gas
are ongoing as a result of mans activity on this
planet.
This is called an anthropogenic effect.