It is estimated that it causes more ozone depletion than cfcs. Pollution control includes prevention, technology, and innovation. Ozone protects living organisms by absorbing harmful ultraviolet radiation uvb from the sun. The evolution of policy responses to stratospheric ozone. Rhode island ozone attainment demonstration submitted on april 30, 2008. Ozone depletion is allowing the uv radiation to earth surface. Effects of ozone depletion for humans and the environment. The ozone depletion phenomenon the ozone depletion. Ozone and uv changes the smaller ozone hole in the spring of 2002 should not be interpreted as a sign of early recovery of the ozone layer the extent of antarctic ozone depletion varies greatly from year to year depending on meteorological conditions. As our scientific knowledge about ozone depletion grew, so too did the response to the issue. It takes years for cfcs and other ozone depleting compounds to reach the stratosphere. Chapter 15 atmospheric pollution and stratospheric ozone.
Stratospheric ozone depletion after reading this module, you should be able to explain the benefits of stratospheric ozone and how it forms. It is revealed that introduction of chloroflourocarbons cfcs in the environment is the most rated cause of said depiction. The questions address the nature of atmospheric ozone, the chemicals that cause ozone depletion, how global and polar ozone depletion occur, and what could lie ahead for the ozone layer. Stratospheric ozone depletion cannot be a principal cause of presentday global climate change for two reasons. In 1985, the scientists published an article in nature announcing that stratospheric ozone over antarctica was reduced 40% in september, the end of the austral winter. Ozone layer depletion government policyunited states.
Under the commonwealth ozone protection and synthetic greenhouse gas. Evidence implicating solar uvr, especially uvb, in every tissue of the eye continues to be amassed. The response to the ozone crisis by dupont, the inventor of cfcs and the largest producer of ozone depleting chemicals in the world is a prime example of the 3d corporate strategy. The latter phenomenon is referred to as the ozone hole.
International conference on ozone layer depletion and pollution prevention scheduled on april 2627, 2022 at istanbul, turkey is for the researchers, scientists, scholars, engineers, academic, scientific and university practitioners to present research activities that might want to attend events, meetings, seminars, congresses, workshops, summit, and symposiums. During the long winter months of darkness over the antarctic, atmospheric temperatures drop. The health effect on humans from ozone depletion is widely varied. There are natural processes that create and destroy ozone in the stratosphere. Ozone layer depletion environmental aspectsunited states. At the end of 20, 258 projects have been committed for an. The causes, mechanism and bioeffects of ozone layer. National aeronautics and the ozone hole space administratio n. Uv radiation would also affect the environment adversely leading to decreased productivity. Negative effects include increases in certain types of skin cancers, eye cataracts and immune deficiency disorders. Ozone depletion in canada is usually greatest in the late winter and early spring. Molina discovered that chlorofluorocarbons cfcs could deplete earths atmospheric ozone layer, which blocks the suns damaging ultraviolet rays. Causes of ozone layer depletion and its effects on human. Market analysis shows that future ozone depletion is based on the continuous flourishing of the space industry and the known impacts of rocket launches.
Ozone depleting substances are the substances such as chlorofluorocarbons, halons, carbon tetrachloride, hydrofluorocarbons, etc. Following is the list of some main ozone depleting substances and the sources from where they are released. Since the ozone layer absorbs uvb ultraviolet light from the sun, ozone layer depletion increases surface uvb levels all else equal, which could lead to damage, including an increase in skin cancer. This website addresses stratospheric ozone issues, including the science of ozone depletion, epas regulatory approach to protecting the ozone layer, epa.
The invisible shield is the ozone layer located in the stratosphere, which starts about 10 miles above the surface and contains about 90 percent of all the ozone molecules in the atmosphere. Some halocarbons ozone depleting substances, or odss deplete the ozone layer, while others greenhouse gases, or ghgs are thought to contribute to global warming. Ozone layer depletion pennsylvania state university. Satellite data indicate that the ozone hole in 2003 developed rapidly and. Under the present arrangements, fully halogenated chlorofluorocarbons, halons and carbon tetrachloride will be phased out by the year 2000, and methylchloroform by the year 2005. In 1974, scientists discovered that emissions of chlorofluo rocarbons, or cfcs, were depleting ozone in the stratosphere. Ozone layer depletion cause, effects, and solutions. Ozone and environment ozone o3 a gas composed of three atoms of oxygen bluish gas that is harmful to breathe nearly 90% of the earths ozone is in the stratosphere and is referred to as the ozone layer ozone absorbs a band of ultraviolet radiation called uvb ozone depleting substances ods. They are usually used as a coolant in refrigerators and air conditioners used in cars etc. Stratospheric ozone depletion through catalytic chemistry involving manmade chloro. Protecting the ozone layer and reducing global warming. The sensitivity of the ozone layer to chemical depletion and climate change was published in 1998, based on research carried out from the 1960s to the mid1990s. Fauna on earth is also adversely affected by the ozone layer depletion.
Aug 28, 2015 ozone layer depletion, is simply the wearing out reduction of the amount of ozone in the stratosphere. August 2010 fact sheet on depletion of the ozone layer and consequent increase in uv radiation reaching the earths surface, with information on the sunwise program and what citizens can do. Experts blame ozone layer depletion on manmade chemicals containing chlorine and bromine that are emitted from a. Protocol on substances that deplete the ozone layer. However, these do not cause more than 1 2% of the ozone depletion. Over the last 10 years, significant advances have been made in ozone depletion science, namely in monitoring. It protects us from harmful uv rays that can have serious effects on animals, biodiversity and peoples health, including skin cancer and eye cataract. What is ozone depletion burning issues free pdf download. These layers are saving us in different ways that most of us dont knows. Protecting the ozone layer department of the environment and.
Since ozone is the earths protection against ultraviolet uv radiation, a reduction in the ozone layer causes more uvb wavelengths to reach the surface of the earth. Odp is a relative value of the ozone destructive potential of a chemical substance by unit weight emitted into atmosphere. Us epa, oar, stratospheric protection division subject. Some ozone also exists in the troposphere, when industrial pollutants react in the presence of sunlight. Ozone layer depletion is the gradual thinning of the earths ozone layer in the upper atmosphere caused due to the release of chemical compounds containing gaseous bromine or chlorine from industries or other human activities. In fact, according to the ozone secretariat, in absence of the protocol, global cfc consumption would have been about 3 million tons in 2010 and would have reached 8 million tons in 2060, which would have resulted in a 50 per cent depletion of the ozone layer by 2035 unep ozone secretariat 2018. The question is often asked why the world moved so quickly in dealing with ozone layer depletion, yet has moved so slowly in addressing the equally critical problem of climate change. In the 1980s, scientists knew that the ozone layer was being damaged by ozone depleting substances odss, which were specific manufactured chemicals e. The layers which occupy the lower part of the atmosphere removes the unwanted pollutants from the earths surface.
The emission of ozone depleting substances has been damaging the ozone layer. There are also springtime polar tropospheric ozone depletion. The stratospheric ozone layer shields the earth from harmful uvb radiation. In the 1980s, scientists found evidence that the ozone layer was being depleted. Undps work on ozone layer protection and programme impact. Feb 12, 2021 ozone depletion, gradual thinning of earths ozone layer caused by the release of chemical compounds containing gaseous chlorine or bromine from industry and other human activities. The full assessment report will be part of the information upon which the parties to the united nations montreal protocol will base their future decisions regarding protection of the earths stratospheric ozone layer. Concern about the ozone depleting potential of manmade chemicals has led the united nations to control their usage. The ozone layer, situated in the stratosphere about 15 to 30 km above the earths surface.
Chlorofluorocarbons and ozone depletion at the university of california, irvine, f. Project ozone layer depletion pdf the stratospheric ozone layer forms a thin shield in the upper atmosphere, protecting life on earth from. The thinning of the ozone layer has increased the risk that australians already face from overexposure to uv radiation from an outdoor lifestyle. Ozone layer protection act faolex database food and. The present document contains key summaries from the scientific assessment of ozone depletion. The ozone hole is not really a hole but a thinning of the ozone layer over the south polar region.
See kerr, ozone hole bodes ill for the globe, 241 science 785 1988. Depletion of the ozone layer stratospheric ozone concentration. Ozone depleting chemicals odc excise tax audit techniques guide. Depletion of the ozone layer results in increased uv radiation reaching the earths surface, which in turn leads to a greater. No one knows for certain how much more ozone depletion will occur. The ozone layer resides in the stratospheric layer of the earths atmosphere. Protecting the ozone layer and reducing global warming undp. Protecting the ozone layer department of the environment.
With so much worry about the rapid ozone depletion taking place in various parts of the earth, indian scientists are closely monitoring the ozone layer over india for possible depletion trends. This report updates the science, looking into how the arctic ozone layer has evolved since 1998. Ozone layer depletion causes and effects of ozone layer. Ozone depletion consists of two related events observed since the late 1970s. Depletion of the ozone layer results in increased uv radiation reaching the earths surface, which in turn leads to a greater chance of overexposure to uv radiation and the related health effects of skin cancer, cataracts, and. Experts blame ozone layer depletion on manmade chem icals containing. When the scientists reported their findings in 1974, cfcs were in wide. The causes, mechanism and bioeffects of ozone layer depletion on humans were addressed. On june 30, 1975 a du pont advertisement in the new york times read. The ozone layer is being destroyed by cfcs and other substances. Additional research has shown that ozone depletion occurs over every continent.
International conference on ozone layer depletion and. The reason behind the ozone layer depletion is mainly due to the extensive use of ozone depleting substances ods. The most recent information is based on work reported in the world meteorological organizations scientific assessment of ozone depletion. The antarctic ozone hole, as it came to be known, made depletion of. In 1987, leaders from many countries came together to sign a landmark environmental treaty, the montreal protocol on substances that deplete the ozone layer. The stratospheric ozone layer forms a thin shield in the upper atmosphere, protecting life on earth from the suns ultraviolet uv rays. Ozone depletion progressing globally except in the tropical zone. Based on this scientific information, the nations of the world took action in 1985 with the vienna convention for the protection of the ozone layer, followed by the montreal protocol on substances that deplete the ozone layer in 1987. But through domestic and international action, the ozone layer is healing and should fully recover by about 2065.
Like an infection that grows more and more virulent, the continentsize hole in earths ozone layer keeps getting bigger and bigger each year since the late 1970s, much of the protective layer of stratospheric ozone above antarctica has disappeared during september, creating what is popularly known as the ozone hole. Convention on protection of the ozone layer and its montreal. Every year, since at least 1978, there is a sudden, rapid decrease in the stratospheric ozone levels at the end of the antarctic winter. When highenergy ultraviolet rays uvc strike an oxygen. Cfcs, hcfcs, halons, methyl bromide, carbon tetrachloride, and methyl chloroform. The use of cfcs is one of the main reasons for the depletion of the layer. Aware that meaeures taken to protect the ozone layer from depletion ahould be baaed on relevant ecientific knowledge, taking into account teclmical and economic conaiderationa, deterained to protect the ozone layer by taking precautionary aea1ure1 to.
The thinning of the ozone layer has increased the risk that australians already face from overexposure to. Depletion of the ozone layer results in increased uv. Within the stratosphere, the ozone layer is the portion that contains the highest. Ozone control strategies groundlevel ozone new england. The depletion of the ozone layer is a serious issue and various programmes have been launched by the government of various countries to prevent it. Ozone layer depletion causes increased uv radiation levels at the earths surface, which is damaging to human health. In the late 1990s, average ozone depletion in the summer over canada was between 3% and 7%. The thinning is most pronounced in the polar regions, especially over antarctica. Vienna convention for the protection of the ozone layer, march 22, 1985, reprinted. Depletion begins when cfcs get into the stratosphere. As a result, there has been a general thinning of the ozone layer over most of the globe, including between five to nine per cent depletion over australia since the 1960s. In 1977 the united nations environment programme unep concluded a world plan of action on the ozone layer, which called for intensive international research and monitoring of the ozone layer, and in 1981, uneps governing council authorized unep to draft a global framework convention on stratospheric ozone protection. The ozone layer over southern canada has thinned by an average of about 7% since the 1980s.
The need for ocular uv protection existed before the discovery of the depletion of the ozone layer and will continue even when the layer fully recovers in approximately 2100. To the point where a seasonal hole in the ozone layer began to appear above the antarctic. Research into ozone depletion has therefore focused largely,though not exclusively,on trends and processes within the stratosphere,the layer of stratified, relatively stable air that houses the ozone layer and. In 1987, leaders from many countries came together to sign a. Ozone depletion and global warming overview page 1 of 5 halocarbons are chemical compounds containing carbon, one or more halogens, and sometimes hydrogen. Fees may vary for courses offered at partner colleges across ontario. The vienna convention for the protection of the ozone layer is a multilateral environmental agreement signed in 1985 that provided frameworks for international reductions in the production of chlorofluorocarbons due to their contribution to the destruction of the ozone layer, resulting in an increased threat of skin cancer.
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