A Planet in Peril:
The Deal on Ozone Depletion
Mickey Croxton
Capstone Senior Project
Mrs. Johnson and Ms. Santer
March 7, 2012
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For billions of years, life on Earth has been protected from the Sun’s harmful UV-B rays,
thanks to stratospheric ozone that encompasses the planet. But what would happen to life if
there were no ozone layer? Life would have developed very differently as organisms would
need to protect themselves from harsher radiation or the planet could very well be inhabitable.
The argument that humans have had a negative impact on the ozone layer has been a hot topic
in politics, news, and casual discussion since the 1970s. The most well-known part of ozone
depletion is the very real fact of a hole in the ozone layer that has formed over Antarctica. If
humans disregard their impact on stratospheric ozone depletion, then they are jeopardizing the
sustainability of future generations for animals and humans alike. Allowing this radiation to
pass through Earth’s atmosphere will hurt all of the planet’s inhabitants and cause major
changes to life. The ozone layer has been altered due to human activity so government needs
to create stronger regulation concerning emission control to protect life on Earth.
The ozone layer protects life on Earth from dangerous ultraviolet-B radiation (UV-B) that
cause skin cancer and cataracts, among other problems. This layer is found in the stratosphere
and inhabits the section that ranges from 9.3 to 18.6 miles above ground. UV-B restricts
reproduction in phytoplankton, leaving less food available for herbivores which in turn leaves
less food for carnivores, meaning reduced rates of fish, crabs and shrimp in the world’s oceans.
Not only does that reduce the populations of those species but the UV-B rays directly impact
their reproductive cycles as well (National Geographic 1-2). With less seafood for humans,
countries that rely heavily on fish populations, like Japan, will be severally hurt.
What from human activity contributes to the depletion of the ozone layer? The chief
contributing pollutants are chlorofluorocarbons or CFCs. However, some scientists disagree on
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whether or not these molecules could actually be the culprit. They contend that CFCs couldn’t
reach the stratosphere because these molecules are much denser than air and therefore
cannot float into the atmosphere. Renowned climatologist Kenneth Ring argues that “CFCs are
so dense that even as a gas you could fill a bucket with it and pour the contents of one bucket
into another” (1). It is true that CFCs are denser than air and in a room with no wind, CFCs will
not rise above the floor. But as any person can walk outside and feel, Earth is anything but
stagnant in regards to air currents. When two liquids have different densities, you can see that
they stack on top of each other in layers but when stirred, they mix. Think of the air and CFCs as
the two liquids and the air currents as the action of stirring. Because of this, the two
compounds are able to mix together and the CFCs are able to rise into the atmosphere
(Environmental Protection Agency) since as Ring correctly points out, CFCs are very stable.
Because of this stability, they are able to float through the troposphere into the stratosphere
where UV radiation is able to pull apart the compound into the three basic elements. So even
though CFCs are comparable to bricks in water and Ring is correct when he obviously states
that “[it] is not often that you will see a brick floating to the surface of your pool” (Ring 1), in
this instance, “bricks” are given the chance to float.
Other experts claim that humans are incapable of depleting the ozone layer simply
because it isn’t possible for man-kind to produce enough pollutants. To say that humans are
unable to produce enough pollution to alter the Earth is incorrect. Humans can clearly produce
enough 𝐶𝑂2 to heat the Earth and cause a multitude of environmental problems, like the
melting of glaciers, habitat destruction and rising seas to name a few. Ever since
industrialization, the Earth has seen ever increasing amounts of 𝐶𝑂2 in the atmosphere. This
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increase in 𝐶𝑂2 leads to an increase in global temperature. According to the United States
Environmental Protection Agency, “the average surface temperature [of Earth] has warmed
about 1°F” since the 1970s which has lead to the previously stated problems.
So this shows that human activity can indeed change the planet’s environment.
Opponents who argue that ozone depletion is not man-made state that the amount of chlorine
found in hydrochloric acid (HCl) released by volcanic eruptions easily outnumbers the amount
of chlorine found in man-made CFC molecules. To say humans couldn’t produce enough
chlorine to alter the already fragile ozone layer through CFCs and other compounds containing
chlorine is false. What matters is how much of that chlorine reaches the stratosphere.
According to Azadeh Tabazadeh, a NASA scientist, “A 'volcanic ozone hole' is likely to occur over
the Arctic within the next 30 years” (qtd. ScienceDaily). The fact of the matter is that most
volcanic eruptions don’t even reach into the stratosphere due to the fact that the eruptions
aren’t strong enough. Because of this, the HCl starts in the troposphere and would actually
have to remain in the air for 2-5 years before ever reaching into the ozone layer. But because
HCl is highly soluble in water, rainwater is able to wash away and cleanse the troposphere of
this source of chlorine. But, unlike HCl, CFCs are very stable and are not soluble in water,
allowing them to reach the stratosphere without being dissolved (Environmental Protection
Agency).
While most volcanic activity does not contribute to ozone depletion, there have been
rare exceptions. One such event when volcanic HCl reached the stratosphere was during the El
Chichon eruption. This volcano is located in Mexico and erupted in 1982 (Smithsonian National
Museum), launching HCl directly into the stratosphere due to the unusual power of its eruption.
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But even in the case of large eruptions, like El Chichon, the chlorine disappeared within the year
unlike the life of CFCs which average around a century of stability (Evans 74). In fact, the EPA
estimated that only 3% of stratospheric chlorine came from volcanoes while a staggering 82%
came from Ozone Depleting Substances (ODS) with 51% of that chlorine from CFCs.
This unclouded causal relationship between CFCs and ozone depletion in the
stratosphere is extremely well established. How CFCs cause ozone depletion has to do with the
stability of the CFC molecule. Because the stratosphere starts high up in the atmosphere, many
unstable molecules cannot reach it. Unfortunately, CFCs are anything but unstable.
Environmental engineer Kim Masters Evans writes, “CFCs are extremely stable; it is this stability
that allows them to float intact through the troposphere and into the ozone layer” (74). Other
chemicals and molecules that contain chlorine, like HCl, can be dissolved by water easily so it
rarely reaches the stratosphere and causes damage to the ozone layer. But because CFCs are
not soluble in water, they can reach up into the ozone layer with ease. CFC production steadily
grew until the 1960s where production skyrocketed, reaching a staggering global production of
1.2 million tons in just one year in the late 1980s (Lomborg 274). After that, CFC production fell,
coinciding to rising ozone levels. When CFC production was at its highest, the amount of ozone
in the stratosphere was at its lowest up until the 1990s. But even after CFC production slowed
down, the ozone levels kept falling until 1994 where ozone levels came down to 92 Dobson
units from 225 Dobson units just 15 years ago. The reason for this time lapse is that CFC
molecules take a couple of years to reach the stratosphere so because of the length time
between initial production and reaching the ozone layer is so large, there’s a delay in the levels
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of ozone. Since then, ozone levels have risen to 112 Dobson units in 2008. Hope is on the
horizon.
But do CFCs have the potential to actually destroy all this ozone causing horrendous
effects or are the connections between ozone and CFCs a coincidence? No, there is no
coincidence between falling ozone levels and rising CFC production levels. Once CFCs reach the
atmosphere, the sun’s UV-B rays break apart the CFC molecule, ripping off the chlorine atom in
the process. The chlorine is then free to interact with ozone molecules which will react to make
oxygen and a new compound, destroying the ozone molecules. With just one atom of chlorine,
over one-hundred thousand ozone atoms can be destroyed until they fall back down into the
troposphere as HCl molecules and get dissolved by rain. But not only does chlorine have
incredible destructive power, the fact that CFCs are not uncommon escalates the problem
further.
However, that process doesn’t happen overnight or even over the course of a few years.
The most common CFC molecules are CFC-11, CFC-12 and CFC-13. These three isotopes are also
some of the molecules that last the longest in the atmosphere. The isotope, CFC-11, lasts 45
years in the stratosphere before its destructive effects are diminished. The second is CFC-12
and lasts for a century in the ozone layer, more than double the time of the CFC-11 molecule.
But the CFC-13 isotope lasts even longer than those two. It lasts for 640 years before
disappearing. But once again, another CFC isotope can dwarf all three, although not as
common. The isotope CFC-115 has the potential to stay in the stratosphere for 1,700 years
destroying ozone molecules for seemingly unbelievable amounts of time (Evans 73-74). There is
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no doubt that molecules with this great destructive ability tied to a long lifespan is the primary
cause of ozone depletion.
During the 1990s, CFC production slowed, but not because companies decided it was
economically feasible. CFC production slowed because multiple nations got together and
crafted the Montreal Protocol. The Montreal Protocol was constructed by 20 nations in the
1980s to stop CFC production because they saw the danger ozone depleting substances were
posing. This protocol had companies phase out these chemicals which included halons, carbon
tetrachloride, and of course, CFCs. In developed countries, CFCs were determined to be
removed from production by 1996 while in developing countries, the deadline was set for 2010.
Looking back at the ozone levels, we see that starting in the 1990s, the steady increase of ozone
following the Montreal Protocol. Since its induction, the United Nations Environmental
Programme (UNEP) announced that by 2006, 191 had ratified it and those countries had seen
more than a 95% drop in the use of the chemicals banned in the agreement (Evans 75-76).
Human production of CFCs has led to the substantial decline in stratospheric ozone and
while the crisis is being fixed, more needs to be done. The UNEP estimates that the
stratospheric ozone will return to its levels before 1980 by 2050 to 2075. Many scientists give
the same 50 year outlook. But ozone depleting substances were not entirely eliminated by the
Montreal Protocol. When CFCs were phased out, hydrochlorofluorocarbons (HCFCs) were
created to take its place with a life span ranging between just over a year to almost 18 years.
These are supposed to be phased out by the Montreal Protocol but what’s to say some other
chemical won’t take its place? (Evans 74-76). Governments need to create even stricter
legislation, modeling the Montreal Protocol, to prevent the creation of new ozone depleting
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substances. Even though HCFCs last much shorter in the stratosphere, they still cause damage
and we still are unaware of the long term consequences of ozone depletion. Governments
should be putting the environment before business because there won’t be businesses if there
is no environment. Countries and businesses alike are becoming more green and are taking
giant steps forward but only if it is economically-friendly. Corporations are in the business for
the money, not for preserving the planet which is where government regulation needs to step
in. The Montreal Protocol should be revised to have shorter phase out times and include more
chemicals. For example, HCFCs are supposed to be phased out by 2030 by developed nations
and 2040 by undeveloped nations. Those times should be cut by a decade at the minimum.
With human ingenuity, the issue is not the lack of technology but the lack of willingness.
Humans cannot wait until we reach the point of no return. Society must act while it still can and
that time is now.
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Works Cited
“Air Pollutants.” US Environmental Protection Agency. United States Government, 19 July 2011. Web. 25
Jan. 2012. <http://www.epa.gov/oar/airpollutants.html>. This web article is a secondary source
that was found on the Environmental Protection Agency website. The Environmental Protection
Agency is a branch of the government departments and is designated in protecting the
environment in the U.S. This was made to spread awareness to the public of specific air
pollutants. It gives links to more information about those pollutants. This source will help me
learn about the many different air pollutants and how each of them negatively impact the
atmosphere. The outline of the information is not consistent across all the pages, making finding
information quickly, difficult.
Evans, Kim Masters. The Environment: A Revolution in Attitudes. Farmington Hills, Michigan: Gage, 2010.
Print. This is a secondary source in the form of a book published by Gage, written by Kim
Masters Evans. Gage provides libraries, schools, and businesses with informations for
employees. students and anyone interested in learning about a particular subject. Evans himself
is an environmental engineer. The section of the book that is helpful is about Ozone Depleting
Substances and will help me with some strong background information on CFCs and how they
break down ozone. The limitations of this source are that it has bias towards the
environmentalist point of view and doesn’t provide the counter argument.
Lomborg, Bjorn. The Skeptical Environmentalist. Cambridge, United Kingdom: Cambridge University
Press, 2001. Print. This book written by Bjorn Lomborg is a secondary source. Lomborg is a
professor and has been honored many times by magazines. Time named him one of the most
influential people in the world in 2004 just to name one. This book is about the environment
and his view on it. There is one part about the ozone layer that has some interesting graphs that
appear helpful. The limitation of this book is that its prime focus is not on the ozone layer.
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NASA/Goddard Space Flight Center. “Future Volcanic Eruptions May Cause Ozone Hole Over Arctic.”
ScienceDaily. N.p., 6 Mar. 2002. Web. 26 Feb. 2012. <http://www.sciencedaily.com/releases/
2002/03/020306073904.htm>. This is a secondary source reprinted on Science Daily from NASA.
NASA is a government organization that focuses on the atmosphere and space. This article talks
about how there could be a ozone hole over the Arctic, similar to the one over Antarctica but
this one would be the cause of volcanoes. This will help me in my counter-argument. The
limitations are that it is brief.
National Geographic. “Ozone Depletion.” National Geographic. N.p., 2011. Web. 15 Dec. 2011.
<http://environment.nationalgeographic.com/environment/global-warming/ozone-depletionoverview/>. This source is a web article by National Geographic, a company that shows nature
and the environment so they know what they’re talking about. This is a secondary source that
talks about some air pollutants and tries to teach the public about air pollution and inform them
of the issue at hand. This will be used to understand some of the pollutants that are released
into the air. The limitations for this source are that it’s a little on the short side so it won’t be
able to go into detail.
Ring, Ken. “The Nonsense That is Ozone-Depletion.” Our Civilization . N.p., Feb. 2011. Web. 26 Feb.
2012. <http://www.ourcivilisation.com/ozone/king.htm>. This is a secondary source that was
found as a web article is written by Ken Ring. Ring is a professional climatologist and is widely
known for successful long-term climate predictions. This source discusses how ozone depletion
by humans isn’t possible by talking about CFCs and how they’re heavier than air. This will help
me with my counter-argument because I can prove him wrong. The limitations on this are that
it’s a pretty short paper.
Smithsonian National Museum. “El Chichón.” Global Volcanism Program. Smithsonian , 2010. Web. 6
Mar. 2012. <http://www.volcano.si.edu/world/volcano.cfm?vnum=1401-12=>. This secondary
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source is a web site, created by the Smithsonian National Museum. As a museum, the institution
goes out into the field and studies many different aspects of history. This website shows the
different volcanoes and facts about them. This source will prove helpful for providing
background details on El Chichon. The limitations are that the facts about it are few and not
extremely detailed.
Works Consulted
Inhofe, James M. “Climate Change Update.” Senate Floor. 4 Jan. 2005. Senate. Web. 25 Jan. 2012.
<http://inhofe.senate.gov/pressreleases/climateupdate.htm>. This source is a speech from the
Congress floor, making it a primary source. The speaker is James M. Inhofe, who is a Republican
representative from Oklahoma. This makes the speaker credible because they had to conduct
study in order to debate properly. This speech is an attempt to sway the Congress to believe
that global warming has no real scientific support. This will be used to see the other side of the
debate over climate change. It does have a Republican bias since they don’t like regulation and
can be affected by outside influence, like lobbyists.
LaFraniere, Sharon. New York Times 27 Jan. 2012: n. pag. New York Times. Web. 1 Feb. 2012.
<http://www.nytimes.com/2012/01/28/world/asia/internet-criticism-pushes-china-to-act-onair-pollution.html?_r=1&ref=airpollution>. This source is a newspaper reposted on the New York
Times newspaper which is a secondary source. The author, LaFraniere, is an American journalist
that previously worked at the Washington Post. This article is about how criticism, spawned
from the Internet, forced China’s government to admit that their cities are dangerously polluted
by buying an independent group to monitor the hourly readings of pollution. The article states
that the citizens of China are becoming more aware of the problem in their country as the
secrets the Chinese government kept hidden are revealed. This will be used to see the public
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opinion on the issue and how the common person can make a difference in their government
and in their world. The limitation is that this is only focused in one country.
Lawrence Berkeley National Laboratory. “Indoor and Outdoor Air Pollution.” Lawrence Berkeley National
Laboratory’s ELSI Project. United States Government, n.d. Web. 25 Jan. 2012.
<http://www.lbl.gov/Education/ELSI/pollution-main.html>. This web article is a secondary
source by a laboratory under the control of the Department of Energy, making this website very
credible since it’s a department of the government. The purpose of this source is to display
information about air pollution and health risks. This will be used to learn about air pollution
and how to prevent harm from it. The limitation of this source is that it only has a general
overview and doesn’t go into detail.
Maduro, Rogelio. “The Holes in the Ozone Hole -- The Scientific Evidence That The Sky Isn’t Falling.”
American Almanac. N.p., Jan. 1994. Web. 15 Dec. 2011. <http://american_almanac.tripod.com/
cfc.htm>. This web article is a secondary source written by Rogelio Maduro, printed in the
American Almanac in 1994. Rogelio Maduro has a bachelors degree in geology and is the
associate editor of 21st Century Science & Technology. The purpose of this is to refute the
claims that our world is in immediate danger of collapse. This will be used to see the other side
of the argument which is extremely helpful since I had trouble finding sources that think climate
change isn’t real or at least exaggerated. The limit of this source is that it’s a little outdated.
NASA Ozone Watch. “Ozone Hole Watch.” NASA. N.p., 22 Jan. 2012. Web. 25 Jan. 2012.
<http://ozonewatch.gsfc.nasa.gov/>. This web article is a secondary source by NASA, which
must know about the condition of the atmosphere in order their astronauts don’t get killed. This
makes them a very credible author. The purpose of this site is to display their pictures of the
ozone layer to the public while giving good information. This will be used to paint a visual
picture of what’s going on so I can better understand the issue at hand. The limitation for this
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source is that it’s pretty brief and won’t give me as much good information as some of the other
sources I have.
Tang, Tianji, et al. “An Overview of Federal Air Quality Legislation.” US Department of Transportation.
United States Government, n.d. Web. 1 Feb. 2012. <http://www.fhwa.dot.gov/resourcecenter/
teams/airquality/teamaq_law.pdf>. This is a secondary source regarding Federal Air Quality
legislation. The United States Department of Transportation is part of the government.The
purpose of this source is to show the history of legislation on air quality. It shows a timeline of
legislation, successive legislation changes, and the different impacts these bills had. This will be
used to see what the rules are now and what changes have been made in the past. The
limitations of this is that while it offers a comprehensive view of legislation, its from the
transportation industry and is geared towards them.