The document summarizes a seminar report on ozone layer depletion and the Montreal Protocol. It discusses how the ozone layer was discovered and its importance in shielding Earth from UV rays. It then explains how CFCs and other ozone depleting substances released from industrial activities were depleting the ozone layer, leading to the formation of an ozone hole over Antarctica. The Montreal Protocol of 1989 was a major international agreement to phase out the production of CFCs and other ozone depleting substances to allow the ozone layer to recover.

1. Seminar Report on
OZONE LAYER DEPLETION & THE
MONTREAL PROTOCOL
2014-2015
Chetan Sharma
M.Sc. I sem.
School Of Studies In Environment Management
Vikram University, Ujjain

2.  Introduction
 Ozone layer formation
 Ozone layer depletion
 Effects depletion
 The Montreal protocol
 Conclusion
 Reference
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SYNOPSIS

3. INTRODUCTION
The ozone layer was discovered in 1913 by the French physicists Charles
Fabry and Henri Buisson.
Ozone layer is a thin, fragile shield that contains relatively high
concentrations of ozone.
It shields the entire Earth from much of the harmful UV radiation that
comes from the sun
The atmosphere of the Earth is divided into 5 layers.
The layers are: troposphere, stratosphere, mesosphere, thermosphere
and exosphere.
Ozone is a triatomic form of oxygen (O3) found in Earth’s upper and
lower atmosphere.
 Humans rely heavily on the absorption of ultraviolet B rays by the ozone
layer because UV-B radiation causes skin cancer and can lead to genetic
damage.
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4. Layers of the Earth’s Atmosphere
Ozone is found in both the troposphere (lower atmosphere) and the stratosphere

5. Ozone formation
Ozone (O3)
 Chemically forms when UV hits on stratosphere
 Oxygen molecules dissociate into atomic oxygen
 Atomic oxygen quickly combines with other oxygen molecules
to form ozone
O2 O + O
O + O2 O3

6. THE OZONE LAYER DEPLETION
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7. Ozone layer is being
destroyed by a group of
manufactured
chemicals that are
called ODS or Ozone-
Depleting Substances.

8. The main ODS are the following:
 Chlorofluorocarbons (CFC 11, CFC
12, CFC 13)
 Methyl bromide (CH3Br)
 Halons (halon-1211, halon-1301,
halon-2402)
 Carbon tetrachloride (CCI4)
 Hydrochloroluorocarbons (HCFC
22 and HCFC 123)

9. THE OZONE HOLE AND ITS CAUSES
 Recently, chlorofluorocarbons (CFCs) were used a lot
in industry and elsewhere to keep things cold and to
make foam and soaps.
 Strong winds carry CFCs up into the stratosphere
where UV radiation breaks them apart, releasing
chlorine atoms.
 Each chlorine atom can attack and break apart
(destroy) as many as 100,000 ozone molecules during
the time it is in the stratosphere.
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10.  The chlorine from CFCs reduces (depletes) the amount of
ozone in the stratosphere.
 Other ozone-eating chemicals are pesticides such as methyl
bromide, halons used in fire extinguishers, and methyl
chloroform used in businesses.
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11. Hole in the ozone layer
October 1979 October 2007

12. Some Effects of Ozone Layer Depletion
Human Health
Damages DNA which suppresses immune system
resulting in increase in infectious diseases e.g. , Skin
Cancer; Eye Cataracts
Plants & Trees
Reduces crop production, damage to seeds
Reduces quality of crops, damage to leaves.
Aquatic Organisms
Damage to plankton, aquatic plants, fish larvae,
shrimp, crabs
Affects marine food chain
Materials
degrades paints, rubber, wood, & plastics,
especially in tropical regions
Ground Level Smog
Increase in the formation of Ground level ozone as a
pollutant
High economic cost
Damages could be in billions of US dollars

13.  An international agreement , signed by most of
the industrialized nations, to substantially
reduce the use of chlorofluorocarbons (CFCs).
 The Montreal Protocol on Substances that
Deplete the Ozone Layer was designed to
reduce the production and consumption of
ozone depleting substances in order to reduce
their abundance in the atmosphere, and
thereby protect the earth’s fragile ozone Layer.
 The protocol set limits on the production of
chlorofluorocarbons (CFCs), halons, and related
substances that release chlorine or bromine to
the ozone layer of the atmosphere.
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THE MONTREAL PROTOCOL(1989)

14. Results to date
 The Montreal Protocol is working.
There is clear evidence of a decrease
in the atmospheric burden of ozone-
depleting substances in the lower
atmosphere and in the stratosphere;
 Some early signs of the expected
stratospheric ozone recovery are also
evident.
 Furthermore, if the Parties were to
eliminate all emissions of ozone
depleting substances soon after 2006,
it would advance by about 15 years
(from around 2050 to 2035) the global
ozone layer recovery to pre-1980
levels
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15. Without the Montreal Protocol by 2050
 Ozone depletion would have reached to at least 50 % in
the northern hemisphere’s mid latitudes
 70% in the southern mid latitudes
 Doubling on the UV-B radiation reaching earth’s surface
 Estimated increases of
 19 million more cases of non-melanoma cancer
 1.5 million more cases of melanoma cancer
 130 million more eye cataracts
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16. There are many possible solutions to this problem, but it
wholly relies on us, humans.. The following are the soltuions
for decreasing the ozone hole in the atmosphere:-
Firstly the consumption all the cfcs should be
 Companies should be held responsible for the disater they
are causing in the environment
 And we should use the 3rs…. Which are reuse , recycle,
reduce initiative… so that the next generation doesnot
have to go through problems made by us.
 And the use of cfcs should be ban.
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CONCLUSION

17. ELEMENTS OF ENVIRONMENT (English) 6th Edition
(1995)by robert smith.
Ecosystem Principles and Sustainable Development
(1999) by swaminatham.
Wikipedia.com/ozone layer
Books.google/ozone layer depletion
REFERENCE
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18. Thank you..