Greenhouse Effect

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Greenhouse Effect
6S Chu Ying Chui 6SCheung Yuet Wah
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WHAT is Greenhouse Effect?

• The greenhouse effect is the natural process by
  which the atmosphere traps some of the Sun's
  energy, warming the Earths surface. Like the
  green house.

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radiation
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IR radiation(heat)
Visible Light
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What are greenhouse gases?
Naturally occurring greenhouse gases Greenhouse gases emitted by human activities
water vapour carbon dioxide methane nitrous oxide ozone Methane Nitrous oxide Ozone Water vapour Halocarbons Carbon Monoxide Chlorofluorocarbons (CFCs) Sulphur Dioxide
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Is it ALL BAD?

• The 'natural greenhouse effect'
• Earth's average surface temperature is kept at
  about 15 C by the blanket of atmosphere that
  surrounds it.
• Without this, the temperature would be about
  minus-18 C, too cold for supporting life.
• ? greenhouse effect is essential to our lives.

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• The 'enhanced greenhouse effect
• Naturally occurring greenhouse gases plays the
  direct role in regulating the climate.
• An increase in these gases in the atmosphere by
  human activities enhances the atmosphere's
  ability to trap heat which in turns increases in
  the average surface temperature of the Earth.
• ?

GLOBAL WARMING!
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How Do Humans Contribute to the Greenhouse Effect?

• Burning natural gas, coal and oil raises the
  level of carbon dioxide in the atmosphere.
• Some farming practices and land-use changes
  increase the levels of methane and nitrous oxide.
  
• Many factories produce long-lasting industrial
  gases add other greenhouse gases to the
  atmosphere.
• Deforestation upset the balance of gases in the
  atmosphere.
• Population growth increase the use fossil fuels,
  more greenhouse gases enter the atmosphere.

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Surface temperature of the arctic are the highest
in 77 years of record keeping.
GREENLAND SURFACE ICE LOSS
Large amount of ice melt lead to the rise of sea
level.Many country will be flood or even FOUNDER.
SOS
SOS
SOS
Ice loss 400 greater than 15years ago
Based on the latest satellite data cited in a
December 2007 article,climate scientist predicts
that nearly all the ice could be gone from the
arctical ocean by THE END OF SUMMER 2012
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What can we DO?

• Use energy much more efficiently
• Accelerate the transition to solar, wind, hydro,
  and biomass energy sources
• Shift fossil fuel use away from coal and oil and
  toward natural gas
• Support Public Transport
• Stop deforestation and accelerate reforestation
• Increase use-efficiency and recycling of all
  materials and of water
• Practice low-input agriculture
• Slow population growth in poor countries

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THE END