Global Warming and Ozone Depletion

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Global Warming and Ozone Depletion
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Table of Contents
Slides 3-8
Global Warming.......
Ozone Depletion......
Slides 9-14
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(No Transcript)
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What Causes Global Warming?
- Global warming is the rise in average global
temperature due to human activities, such as,
the emissions of greenhouse gas pollution
produced by the burning of fossil fuels and
land-use changes like deforestation. Scientists
predict that higher temperatures will probably be
accompanied by an increase in extreme weather
events like flooding and drought, as well as a
rise in the global sea level.   - Light from the
sun passes through the Earth's atmosphere and
heats its surface. The Earth's surface then gives
off heat, some of which is trapped in its
atmosphere by a blanket of greenhouse gases
rather than escaping into space, keeping the
Earth warmer than it otherwise would be. Most of
this greenhouse effect is natural, maintaining
the Earth's average temperature at about 60
degrees Fahrenheit (15 degrees Celsius). Without
the natural greenhouse effect, the Earth's
average temperature would be closer to 0degrees
Fahrenheit (-18 degrees Celsius). - Gases such
as carbon dioxide, methane, nitrous oxide, and
refrigerants create a greenhouse effect by
trapping heat in the lower atmosphere. This makes
the Earth warmer because the suns rays are
allowed into the lower atmosphere but the heat
from these rays isnt able to escape.
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When And Where?

• - Global warming is happening all over the world,
  all the time.
• Changes in our climate are real and they are
  underway. But we can do something about it. The
  evidence that human-induced global warming is
  real is increasingly clear and compelling.
• - Since the beginning of the 20th century, the
  mean surface temperature of the earth has
  increased by about 1.1º F (0.6Celsius).
• - Over the last 40 years, which is the period
  with most reliable data, the temperature
  increased by about 0.5 º F (0.2-0.3Celsius).
• - Warming in the 20th century is greater than at
  any time during the past 400-600 years.

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Occurences
- Global warming is an increase in the average
temperature of the earth's atmosphere, especially
a sustained increase sufficient to cause climatic
change so therefore it has and is occurring in
the area of Windsor. - Recent examples of
major occurrence in global warming were in
Europe. In 2003 Europe received a massive heat
wave. Scientists believed that the conclusion to
this result is that climate change is now
doubling the risk of major heat waves around the
world.
-Also, another example of global warming is that
in the Arctic region, the ice is starting to melt
rather quickly because the global warming is
allowing the sun to give hotter rays onto the
earth.
-Like terrorism, global warming knows no
boundaries. It can strike anywhere, in any form.
It is not just a problem for the future. Global
warming is already upon us.
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Potential for Destruction

• Impacts from Global warming include sea level
  rise, more extreme weather events including heat
  waves, frosts, droughts, storms, extinction of
  species, loss of entire forests, marine life
  destruction
• Some researchers believe that global warming is
  foreshadowing a coming ice-age. The last ice age
  occurred as the Earth's climate was warming. In
  the Arctic regions, more water would evaporate in
  summer, and fall onto the land as snow in winter.
  The winters would not be so warm as to melt all
  of this snow, thus glaciers would grow. Also,
  some carbon compounds released in the atmosphere
  may help prevent global warming. These particles
  reflects sunshine, which is redirected into
  space.

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Other Interesting Facts About Global Warming

• The Kyoto Protocol is an amendment to the United
  Nations Framework Convention on Climate Change
  (UNFCCC), an international treaty on global
  warming. It also reaffirms sections of the
  UNFCCC. Countries which ratify this protocol
  commit to reduce their emissions of carbon
  dioxide and five other greenhouse gases, or
  engage in emissions trading if they maintain or
  increase emissions of these gases. A total of 141
  countries have ratified the agreement.
• Current estimates are that even if successfully
  and completely implemented, the Kyoto Protocol is
  predicted to reduce the average global
  temperature by somewhere between 0.02C and
  0.28C by the year 2050 .
• - using current and cutting-edge technology that
  will reduce our use of fossil fuels. By switching
  to energy efficient cars and trucks, and clean,
  renewable energy, we can curb global warming
  pollution, save consumers money and curtail our
  reliance on oil.

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Ozone Depletion
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What Causes Ozone Depletion

• The ozone layer is located  above the
  troposphere in the stratosphere (10 km to about
  50 km high). Stratospheric ozone is Earths
  natural protection for all life forms, shielding
  our planet from harmful  ultraviolet-B (UV-B)
  radiation.
• UV-B radiation is harmful to humans, animals,
  and plant life. The  ozone layer is being
  destroyed by certain industrial chemicals
  including ozone depleting refrigerants, halons,
  and methyl bromide, a deadly pesticide used on
  crops.

• Ozone depletion damage gets much worse when the
  stratosphere is very cold. This has been the case
  the past two years, causing extensive ozone
  depletion. This past winter, ozone depletion
  reached  the most severe levels ever recorded
  over the Northern Hemisphere. Western United
  States ozone levels also continue to drop 3-4
  percent per decade.  
• - Even if all of our efforts to stop harmful
  emissions are successful, the ozone layer is not
  expected to begin recovery  until around 2020 at
  the earliest.

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When and Where

• Ozone depletion occurs in the stratosphere
• It happens when the natural balance between the
  production and destruction of stratospheric ozone
  is tipped in favour of destruction

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Occurences
Ozone depletion is presented throughout the
whole stratosphere so therefore it has occurred
in the area of Windsor. Recent example of its
occurrence is in the arctic area. Severe
depletion of the Arctic area was first discovered
in the 1980s. Arctic depletion is seasonal
mainly occurring in the late winter and early
spring. This resulted into the ozone hole in the
sky.
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Potential for Destruction
- The ozone helps get rid of the earths
pollution but lately it has been letting the sun
rays come onto the earth, causing UV radiation

• (UV-B) radiation causes skin cancer, cataracts
  and immune suppression in both animals and
  humans.  UV-B also damages plants including
  hardwood forests, and phytoplankton
• Skin Cancer Is Increasing
• - There has been an 1,800 percent rise in
  malignant melanoma since 1930.
• - One American dies of skin cancer every hour.
• - One in five Americans develops skin cancer.
• - People get 80 percent of their lifetime sun
  exposure by age 18.

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Other Facts
- The Montreal Protocol on Substances That
Deplete the Ozone Layer is a landmark
international agreement designed to protect the
stratospheric ozone layer. The treaty was
originally signed in 1987 and substantially
amended in 1990 and 1992. The Montreal Protocol
stipulates that the production and consumption of
compounds that deplete ozone in the stratosphere
are to be phased out.

• Solutions to the ozone layer depletion problem
  have been found but the ones that show the most
  promise are very expensive. The web site "The
  ozone Depletion Phenomenon" suggests in the
  article "solutions", "to build huge metal screens
  that float on helium balloons in the
  troposphere".
• - They continue with "These screens will be
  electrified so that chlorine atoms will become
  negatively charged and unable to destroy ozone
  molecules". The also say that "In order for these
  screens to be effective the screens would have to
  be the size of a football field and a total of 8
  screens would have to circle the earth".

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THE END!