The present act aims to phase out ozone depleting substances. For enforcement and monitoring purposes, owners or operators of industrial commercial. The montreal protocol on substances that deplete the ozone layer. Generally, we find thinning or depletion of the ozone layer to the extent of ozone hole creation over the southern pole i. The ozone hole is not really a hole but a thinning of the ozone layer over the south polar region. The reason behind the ozone layer depletion is mainly due to the extensive use of ozone depleting substances ods. In 1987, the parties adopted the montreal protocol on substances that deplete the ozone layer, with the objective of phasing out the production and consumption of ozone depleting substances. Depletion of the ozone layer results in increased uv radiation reaching the earths surface, which in turn leads to a greater. The objective of the convention is to preserve human health, and to protect the environment from any harmful effects of the depletion of the ozone layer.
Five steps for raising awareness on ozone depletion was prepared by the ozonaction programme of. Some halocarbons ozone depleting substances, or odss deplete the ozone layer, while others greenhouse gases, or ghgs are thought to contribute to global warming. The ozone layer, cfcs and global warming objectives subjects. Knowledge of environmental aspect and impact is necessary in order to have a thorough awareness of the world we live in. Additional research has shown that ozone depletion has occurred on every continent. On june 30, 1975 a du pont advertisement in the new york times read.
The thinning of the ozone layer has increased the risk that australians already face from overexposure to uv radiation from an outdoor lifestyle. Battling for oxygen using gumdrops and toothpicks, students conduct a largegroup, interactive ozone depletion model. Chemists sherwood rowland and mario molina were awarded the nobel prize in 1995, for their earlier discovery that humanmade cfcs were a major factor in ozone layer depletion. Using gumdrops and toothpicks, students conduct a largegroup, interactive ozone depletion model. Explain the greenhouse effect and its potential harmful effects. 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. Poster competition on the theme save ozone save earth was displayed on the walls. Various human activities have resulted in the depletion of the ozone layer. The ozone layer resides in the stratospheric layer of the earths atmosphere. Chlorofluorocarbons and ozone depletion at the university of california, irvine, f. 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.
Protecting the ozone layer and reducing global warming. The thinning or reduction of ozone depletion is most prominent in the polar regions, especially over antarctica. Ozone depletion read earth science ck12 foundation. Nasas existing mission to observe planet earth was augmented in these years and directed more toward environmental quality. The objective of the protocol is to preserve the ozone layer through worldwide control, reduction and ultimately elimination of emissions of ozone depleting substances. Global effects of ozone depletion ozone depletion in the earths atmosphere is under constant scrutiny by the american press and people. Students explore the dynamic and competing upper atmospheric roles of the protective ozone layer, the suns uv radiation and harmful humanmade cfcs chlorofluorocarbons. They are usually used as a coolant in refrigerators and air conditioners used in cars etc. In the morning assembly, speech on preservation of ozone layer. Protecting the ozone layer department of the environment. The causes, mechanism and bioeffects of ozone layer.
The depletion of the stratospheric ozone layer, increases in troposphere ozone, higher levels of acidity in rain, rising carbon dioxide and methane concentrations, and changes in the radiative balance of the earthatmosphere energy system all reflects the increasing influence of human. A new ozone layer protection act plus accompanying regulations came into force in 1996. National aeronautics and the ozone hole space administratio n. Ozone depletioncauses and effects midnapore college. Understand the difference between groundlevel and stratospheric ozone 2. Ozone and ozone layer information technology services. The montreal protocol on substances that deplete the ozone layer, the first global legallybinding environmental treaty, was signed in 1987. 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 antarctic hole now measures about 9 million square miles, nearly the. 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. At the end of 20, 258 projects have been committed for an. The ozone layer absorbs around 9799% of the mediumfrequency ultraviolet light emitted by the sun.
The ozone layer is composed of 3 atoms of oxygen and is represented as o 3. Allow children to practice sustainable ways of living iii. The ozone depletion phenomenon the ozone depletion. Ozone layer protection environmental protection department. Protocol on substances that deplete the ozone layer. Ozone depletion thus represents an important case study in the history of nasa and environmental sciences. Together, they describe what ozone, the ozone layer, ozone depletion and the ozone hole are, how ozone depletion occurs, mankinds influence, its impacts, and the international agreements put in place to control it. The use of cfcs is one of the main reasons for the depletion of the layer. The layers which occupy the lower part of the atmosphere removes the unwanted pollutants from the earths surface. When highenergy ultraviolet rays uvc strike an oxygen. Protecting the ozone layer efforts to reduce ozone depletion montreal protocol, a treaty developed in 1987 cut emissions of cfcs by 35% 50% between 1989 and 2000 60 solutions. There are natural processes that create and destroy ozone in the stratosphere. Capacity must therefore be enhanced for the detection of the early health effects of climate change and stratospheric ozone depletion.
Scientists discovered in the mid1970s that certain manmade chemicals could destroy ozone. Product uses as substitutes for ozone depleting substances. Ozone depletion,on the other hand,is about how certain industrially produced chemicals containing chlorine or bromine are damaging the earths protective ozone layer, thus increasing the intensity of ultraviolet radiation at the earths surface figure 2b. In this picture we are seeing how the ozone layer is destroyed and the effects of that destruction.
Causes of ozone layer depletion and its effects on human. The thinning of the ozone layer has increased the risk that australians already face from overexposure to. Mitigating pollution became an overriding objective for many agencies. The ozone layer vital for life the ozone layer is a layer of gas about 15 km above the earths surface. Let children work and contribute in preserving the ozone layer activity. The montreal protocol on substances that deplete the ozone. Signed 26 august 1987, it was made pursuant to the 1985 vienna convention for the protection of the ozone layer, which. Extinguishing concept lowering ozone depletion and green house effect ecolog project objective project initiated coordinated founded by airbus. To the point where a seasonal hole in the ozone layer began to appear above the antarctic. In the 1980s, scientists found evidence that the ozone layer was being depleted.
Molina discovered that chlorofluorocarbons cfcs could deplete earths atmospheric ozone layer, which blocks the suns damaging ultraviolet rays. Ozone protects living organisms by absorbing harmful ultraviolet radiation uvb from the sun. High up in our atmosphere, it performs a vital role in protecting humans and living things on earth from harmful uvb and uvc rays from the sun. It was designed to stop the production and import of ozone depleting substances. 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 immune. In 1974, scientists discovered that emissions of chlorofluo rocarbons, or cfcs, were depleting ozone in the stratosphere. How to protect the skin and eyes from overexposure to uv radiation. Figure q101 figure q102 stratospheric ozone depletion. The severe depletion of the ozone layer in any particular area is called ozone hole. Conclusions ozone depletion climate policy watcher. The montreal protocol on substances that deplete the ozone layer, also known simply as the montreal protocol, is an international treaty designed to protect the ozone layer by phasing out the production of numerous substances that are responsible for ozone depletion.
Downward trends are evident in the time series of spatially or timeaveraged spring column ozone observations shown in figure 1. The montreal protocol, finalized in 1987, is a global agreement to protect the stratospheric ozone layer by phasing out the production and consumption of ozone depleting substances ods. Global collaboration and regulation aims to reduce the emissions. The ozone layer, situated in the stratosphere about 15 to 30 km above the earths surface. Ecolog extinguishing co lowering ozone depletion and. Satellite data indicate that the ozone hole in 2003 developed rapidly and. 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. 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. The emission of ozonedepleting gases are threatening the earths ozone layer. The ozone layer, located in the upper stratosphere 10 50 km above the earths surface, plays the highly important role in protecting life on this planet by absorbing harmful ultraviolet light uvb with wavelengths of between 280315nm. 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. The world health organization was established in 1948 as a. The goal of this chapter is to evaluate how well ccms simulate natural stratospheric. The answers are updates of those first presented in the previous ozone assessment, scientific assessment of ozone depletion.
When there was no ozone layer, life could only exist in the sea. As a consequence of achieving this overall objective, the gef will also contribute generally to capacity development for the sound management of chemicals. The montreal protocol has proven to be innovative and successful, and is the first treaty to achieve universal ratification by all countries in the world. That link, along with other issues remaining to be understood, has required constant attention. Chlorofluorocarbons cfcs and other halogenated ozone depleting. Indeed, the depletion of the global ozone layer has emerged as one of the major global scienti. Certain compounds such as chlorofluorocarbons, cfcs, are released into the atmosphere by human activities, and these cfcs particularly, they are very, very unreactive at the atmospherical ground level and they go all the way up to the stratosphere and then. Ozone layer depletion environmental aspectsunited states. The stratospheric ozone layer forms a thin shield in the upper atmosphere, protecting life on earth from the suns ultraviolet uv rays. Protection of the ozone layer climate action european commission.
If you need to print pages from this book, we recommend downloading it as a pdf. The european environment and health committee identified the need to assess these topics in 1997, as part of the leadup to the third ministerial conference on envi. This can only be achieved by supporting research, monitoring and assessment. In 1974, molina and rowland published a pivotal study that drew widespread attention to depletion of the stratospheric ozone layer due to emission of manmade. Montreal protocol on substances that deplete the ozone layer. Research into ozone depletion has therefore focused largely. Effects on the health of the human population are likely to become evident within the coming decade. The ozone layer is referred to as a specific region in the earths stratosphere that acts as a shield against the incoming ultraviolet rays of the sun. Depletion of the ozone layer results in increased uv. Its objectives are to promote cooperation on the adverse effects of human. How severe is the depletion of the antarctic ozone layer. The montreal protocols objective is to cut down the production and consumption of ozone depleting substances, in order to reduce their presence in the. Various anthropogenic activities such as emissions of cfcs, hcfcs, and other organohalogens lead to the depletion of ozone. This brochure presents the ozone layer depletion focal area.
Describes how the ozone hole forms and the effects on the environment and life beneath it. Its consequences, the causal debate, and international cooperation number 6 february 8, 1988 since the announcement of a thinning of the ozone layer over the antarctic by uk scientists in 1985, world attention has been focusing on the causes of this phenomenon. This study was conducted at university of gujrat during 20142015 as a term paper for master of philosophy. Unfortunately, this book cant be printed from the openbook. Nov 25, 2020 the ozone layer is a natural layer of gas in the upper atmosphere that protects humans and other living things from harmful ultraviolet uv radiation from the sun. The montreal protocol on substances that deplete the ozone layer a protocol to the vienna convention for. The ozone layer ozone in the stratosphere 1250 km above the surface of the earth absorbs ultraviolet radiation that can lead to skin cancer and other adverse effects 4. Every year, since at least 1978, there is a sudden, rapid decrease in the stratospheric ozone levels at the end of the antarctic winter. A warming trend and stratospheric ozone depletion have been observed in europe over the last four decades. Within the stratosphere, the ozone layer is the portion that contains the highest.
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. Ozone depletion and global warming overview page 1 of 5 halocarbons are chemical compounds containing carbon, one or more halogens, and sometimes hydrogen. The thinning is most pronounced in the polar regions, especially over antarctica. Management and destruction of existing ozone depleting substances banks. Guideline on policy measures for the management and. The ozone layer is being destroyed by cfcs and other substances. Second, the depletion of the stratospheric ozone layer and most notably the antarctic ozone hole has a signi. 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. 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. Take the below quiz to test your knowledge on the ozone layer and its depletion. When the scientists reported their findings in 1974, cfcs were in wide. What is ozone depletion burning issues free pdf download. During the long winter months of darkness over the antarctic, atmospheric temperatures drop.
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