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Greenhouse Effect and Ozone Depletion

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Title: Greenhouse Effect and Ozone Depletion


1
Greenhouse Effect and Ozone Depletion
2
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.

3
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.

4

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

5
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)

6
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

7
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.

8
Negative Effects of Global Warming
9
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.

10
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.

11
Ozone Depletion
12
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.

13
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.
14
THE END
15
By Cherine Chaker, Joe Charron
Erica Lee
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