Evaluation II

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Evaluation II The Atmosphere
Feedback describes the situation when output from
(or information about the result of) an event or
phenomenon in the past will influence the same
event/phenomenon in the present or future. When
an event is part of a chain of cause-and-effect
that forms a circuit or loop, then the event is
said to "feed back" into itself. Feedback the
process in which part of the output of a system
is returned to its input in order to regulate its
further output Feedback the process by which a
system, often biological or ecological, is
modulated, controlled, or changed by the product,
output, or response it produces.
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Basic definition of feedback
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Spectrum of the Suns Incoming Radiation
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Spectrum of the Earths Outgoing Radiation
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http//en.wikipedia.org/wiki/Earths_energy_budget
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Major feedbacks at work in the Earths climate
system

• Water vapor feedback
• Clouds feedbacks
• IR flux Temperature Feedback
• Aerosol feedback
• Snow/Ice-albedo feedback
• Ocean circulation feedback
• Biosphere feedback

See also Page 4 of Reading Notes on Atmosphere,
particularly the diagram on that page showing the
loop that constitutes a feedback.
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Examples of feedbacks that include the
land-atmosphere coupling (This below also applies
to help explain diagrams in question 4).
More High Cloud --gt Warming
Warming --gt Evaporation
More Low Cloud --gt Cooling