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PROTECTION AND MAINTENANCE OF OZONE LAYER
A Report
RAGHUVEER SANTOSH BOMIDI
RAHUL SHEKHAR
RAJESH AJMERA
RAJNISH KUMAR YADAV
RAVI KUMAR
OZONE AND THE OZONE LAYER
. Ozone is formed in the upper atmosphere when oxygen is bombarded by ultraviolet rays in sunlight with shorter wavelength and energy than other components of the visible light.
. Ozone, thus formed, stays as a layer above the earth, known as the ozone layer
THE OZONE LAYER DEPLETION
The Ozone molecules split into oxygen molecules and atoms by absorption of ultraviolet rays. Such reactions (i.e. ozone formation and decomposition) are natural, constant and balanced governed by atmospheric factors and chemical composition of the stratosphere.
Some chemical compounds emitted by human activities such as nitrogen oxides, chlorofluoro carbons (CFCs) and halons help in accelerating the process of ozone molecule decomposition, hence, disturbing the existing natural balance leading to depletion of the ozone layer.
The ozone hole over the South Pole is apparent in this false-color image taken by a satellite in October 1999. Low levels of ozone are shown in blue. Ozone is a gas that blocks harmful ultraviolet sunlight. Industrial chemicals released into the atmosphere have caused ozone to break down, opening holes in the ozone layer that tend to concentrate at the poles.
Click icon to add picture
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WHY IT IS A MATTER OF CONCERN ???
Impacts on health can cause a range of health effects,
including skin damage (skin cancers and premature aging), eye damage (including cataracts), and suppression of the immune
system.
Impacts on plantscan damage sensitive crops, such as
soybeans, and reduce crop yields.
MATERIAL DAMAGES
Ozone depletion will cause many materials to degrade faster. These materials include PVC (used in window and doorframes, pipes and gutters), nylon and polyester.
Synthetic polymers, naturally occurring biopolymers, as well as some other materials of commercial interest are adversely affected by UV radiation from the Sun.
CAUSES OF OZONE LAYER DEPLETION
Although natural phenomena can cause temporary ozone loss, chlorine and bromine released from man-made compounds such as CFC’s are now accepted as the main cause of this depletion.
Ozone is converted to oxygen, leaving the chlorine atom free to repeat the process up to 100,000 times, resulting in a reduced level of ozone.
Bromine compounds, or halons, can also destroy stratospheric ozone.Compounds
SOURCES OF CFCs
ACTIVITIES GOING ON FOR THE PROTECTION OF OZONE LAYER Concern first arose over the damage that CFCs may
cause to the ozone layer in the 1970s.
By 1988 it had been proven conclusively by science that this was due to CFC release into the atmosphere and that the problem would continue for as long they were discharged into the atmosphere .
A total ban on the use of CFCs during the 1990s was proposed by the European union in 1989.
Cont…. In December 1995 over 100 nations agreed to
phase out developed countries' production of the pesticide methyl bromide.
At present , countries around the world are collaborating to develop and test new technologies to eliminate the need for ozone-depleting substances. Many organizations and individuals broke down many technical, institutional, and financial barriers, paving the way for the commercialization and standardization of new materials, products, and processes.
The Vienna Convention
The Vienna Convention on Protection of the Ozone Layer, signed in March 1985, actually represented the first formal international effort to deal with an environmental danger before it erupted.
The convention also established mechanisms for international cooperation in research, monitoring, and exchange of data on the state of the stratospheric ozone layer, and on emissions and concentrations of relevant chemicals.
The Montréal Protocol
The Montréal Protocol was signed and later ratified by 36 nations.
Under the Protocol CFC usage was reduced by 50% by the year 2000.
Most states were persuaded to join, though developing states, led by China and India, were only persuaded to join once a Multilateral Fund was established by the industrialized states to pay the incremental costs occurred by the Protocol.
The Montreal Protocol broke new ground in the planning process.
How we can help to protect ozone layer ???
Using Hydrochlorofluorocarbons (HCFC), as a substitute for Chlorofluorocarbons (CFCs) .
Continuing the implementation of ozone-depleting substance recovery and recycling programs.
Intensifying awareness campaigns on eco-friendly alternatives
Decrease / control releases of high temperature steam / moisture to the atmosphere.
Eliminate production and release of known ozone depleting chemicals (such as CFCs and HCFCs) where remotely possible. Subsidize production of safer alternatives where possible.
Establish controls to assure that new compounds to be used in high volume, are surveyed for effect on ozone.
We can…..Try to use products which are labeled "Ozone-
Friendly"Ensure technicians repairing your refrigerator or
air conditioner recover and recycle the old CFCs so they are not released into the atmosphere.
Vehicle air conditioning units should regularly be checked for leaks.
Ask about converting your car to a substitute refrigerant if the a/c system needs major repair
Help start a refrigerant recovery and recycling program in your area if none already exists.
Replace halon fire extinguishers with alternatives (e.g. carbon dioxide or foam).
Thank you