What is the Problem?
What is Ozone?
Ozone is composed of three Oxygen atoms, and is unstable
(2). The formation of Ozone has been
taking place for many millions of years (6) and its stability is attributed to
Nitrogen compounds in the atmosphere.
In the Stratosphere, Ozone protects the Earth. In the Troposphere, Ozone is dangerous. http://www.ucar.edu/learn/1_5_1.htm |
Picture of Atomic oxygen, Diatomic oxygen, and Ozone. http://www.ucar.edu/learn/1_5_1.htm |
Ozone forms in
the atmosphere by the action of sunlight on oxygen (6). Ozone higher up in the atmosphere protects
life on Earth (2). Ozone lower in the atmosphere (troposphere) can be toxic and
a pollutant (2).
Recognition
of the Problem
In the 1970s
huge loss of Ozone over Antarctica was noticed by the British Antarctica Survey
(5). In 1973 Chlorine was discovered to
be a major cause of Ozone depletion (1).
The process by which the Ozone depletes is that Oxygen is removed from
the Ozone and leaves Chlorine unaffected (1).
When the Chlorine is left in the Ozone, it basically destroys it,
leaving holes for UV-B rays to pass through.
Without Ozone, there is a potential for skin cancer and cataracts
(6). Damage to crops and to plankton
and the marine food web is also present without Ozone (6). When crops are decreased and plant life as
well, carbon dioxide increases and Global Warming is a product of the Ozone
thinning out (6).
Picture of a research station similar
to that in Halley Bay, Antarctica. In the Springtime, the Ozone thins out
and weather satellites indicated that the overall percentage of ozone in the
Antarctica is declining (6). Further studies by balloons and
satellites showed that the percentage of Ozone is declining as well. http://www.atm.ch.cam.ac.uk/tour/part1.html |
The Earth’s Atmosphere http://www.atm.ch.cam.ac.uk/tour/part1.html |
“The World Meteorological Organization
observed a 45 percent depletion of the ozone layer over one-third of the
northern hemisphere, from Greenland to western Siberia, for several days
during the winter of 1995-1996. The deficiency was believed to have been
caused by chlorine and bromine compounds combined with polar stratospheric
clouds formed under unusually low temperatures.” (6) |
With the
problem evident, action was taken to preserve the Ozone.
In 1987, the
Montreal Protocol was signed and ratified by 36 countries (6). It aimed to reduce CFCs
(Chlorofluorocarbons) by half by the year 2000 (5). The European Community had stricter measurements taken, aiming to
halt all production by 1995 (5).
Chlorofluorocarbons
Chlorofluorocarbons
were developed in the 1930s (1). Its
primary uses were for industrial, commercial, and household appliances (1).
CFCs are non-toxic, non-flammable, and non-reactive with other compounds, and
were first invented to replace dangerous Sulfur Dioxide and Ammonia
refrigerants (1). Most CFCs do not dissolve in water, therefore reach the
atmosphere (4).
Human-made halocarbons are the biggest reason for Chlorine
in the atmosphere (4).
http://www-personal.umich.edu/~jlenobel/HumanActivity.html |
When released into the atmosphere, CFCs
rise and are broken down by sunlight (6). The Chlorine molecules interact with
Ozone and destroy it (6). Misconceptions about the Ozone Layer: The Ozone gets confused with Global
Warming (5). The ozone problem is not global
warming, ,but because Carbon Dioxide is released into the atmosphere due to
the killing of plants by radiation, , Global warming does occur. |
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1. http://www-personal.umich.edu/~jlenobel/
Ozone Depletion
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2. http://www-personal.umich.edu/~dparsly/oz-background%201.html
Location, Size, and Concentration of the Ozone Layer
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3. http://www.urbanclimate.org/ozone/Ozone_Formation.qt
The Ozone Clip
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4. http://www-personal.umich.edu/~jlenobel/HumanActivity.html
Human Activity vs. Nature
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5. http://www.atm.ch.cam.ac.uk/tour/part1.html
The Ozone Hole Tour: Part One…The History of the Ozone Layer
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- 6. http://encarta.msn.com/find/Concise.asp?z=1&pg=2&ti=761555692
Encarta Online, Ozone Layer