Greenhouse Effect and Ozone Depletion

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Greenhouse Effect and Ozone Depletion
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What is the Greenhouse Effect?

• The Greenhouse effect is the result of
  greenhouse gases building up in the earths
  atmosphere which causes incoming solar radiation
  to become trapped. As a result, infrared
  radiation causes temperatures to increase because
  it is unable to escape.

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Process of the Greenhouse Effect

• The solar radiation created by the sun enters the
  atmosphere and becomes infrared radiation (heat
  radiation). This radiation then exits the
  atmosphere, leaving only small portions of it
  behind.
• With the Greenhouse effect, there are more water
  vapors and gases in the air, so the infrared
  radiation is absorbed into these gases, creating
  higher temperatures.

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When and Where Greenhouse Effect Occurs?

• The greenhouse effect occurs in our fragile
  atmosphere
• Greenhouse gases are prevalent all over the world
• Therefore the Greenhouse Effect occurs everywhere
  all the time

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Problems of Global Warming

• Causes trouble by increasing the temperature of
  the planet.
• The Inter-Governmental Panel on Climate Change
  predicts that a rise of one degree can occur by
  the year 2025.
• An increase of one degree could possibly destroy
  the North American Corn Belt, which produces most
  of the worlds grain.

• This could raise food prices, and leaves an even
  less food supply for the Third World than they
  already have.
• Another worry is the melting of the polar ice
  caps could rise sea levels and flood many
  countries (15 of Egypt and 12 of Bangladesh)

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Solutions to Global Warming

• To cut down on greenhouse emissions some
  suggestions are
• turn off lights when you leave a room
• Dont use car for short trips
• insulate your house properly
• anything that uses less energy

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What Causes Global Warming?

• Global warming is caused by the excess production
  of gases such as carbon dioxide, nitrous oxide,
  methane, and chlorofluorocarbon (CFC), which
  absorb the suns rays and emit its heat on
  earth, resulting in a higher temperature.

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Negative Effects of Global Warming
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The Effect on Windsor

• In the last ten years, Ontario and Quebec
  experienced record breaking increases in
  temperatures and humidity.
• On July 14, 1995 Windsor recorded the highest
  humidity levels ever in Canada.
• These increases led to almost 20 million dollars
  in the reconstructions due to destructive storms.
  

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The Kyoto Protocol

• The Canadian Government supports companies
  who are in the process of improving and
  advertising electric cars.
• A recent law concerning car companies states
  that they must improve gas mileages.

• 160 Nations, including Canada, met in Kyoto,
  Japan on December 1, 1997 to discuss the serious
  issue of global warming.
• The countries agreed to lower their emissions of
  greenhouse gases. Canadas goal is to lower it by
  6.

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Ozone Depletion
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The Ozone Layer

• The ozone layer acts as a shield, protecting us
  from the suns harmful UV rays.
• Over the past ten years, scientists have noticed
  declining levels of ozone in the atmosphere. This
  means that more UV radiation reaches earth,
  increasing the danger of sun damage, such as sun
  cancer and cataracts. In the 1970s scientists
  discovered that a portion of the ozone layer over
  Antarctica is extremely thin, which is leading to
  Global Warming.

• Most scientists agree that future levels of
  ozone will depend upon a combination of natural
  and man-made factors, including the phase-out of
  chlorofluorocarbons and other ozone-depleting
  chemicals.

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Ozone Depletion How?

• In order for ozone depletion to form, clouds,
  known as PSCs, must form in the ozone layer.
• In the surface of the clouds, a reaction takes
  place. This converts chlorine (which is caused
  by CFCs and other ozone depleting chemicals) into
  an active form, so that when sunlight takes
  place, the ozone is rapidly destroyed.

These clouds form in the center of the ozone
layer only in the Antarctic winters, where it is
cold enough for these particular clouds to
form. Elsewhere, it rarely occurs because it is
not cold enough for these clouds to form.
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THE END
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By Cherine Chaker, Joe Charron
Erica Lee