Depletion of this layer by ozone depleting substances ods will lead to higher uvb levels, which in turn will cause increased skin cancers and cataracts and potential. Oct 27, 2017 the effects of ozone depletion on plants and animals massive amounts of uvb radiation that penetrate our atmosphere do not only affect humans, but also animals and plants. Ozone depletion has also been detected outside the antarctic. Joe farman, brian gardiner, and jonathan shanklin british atlantic survey research station, holly bay, antarctic coast in 1985, using satellites, balloons,in 1985, using satellites, balloons, and surface stations, a team ofand surface stations, a team of researchers had. Progress report 2003 united nations environment programme, environmental e. Stratospheric ozone depletion due to nitrous oxide. Ozone depletion is primarily caused by human activities. Ozone depletion is allowing the uv radiation to earth surface. 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. This proves ozone depletion is a big issue that needs. The thinning of the ozone layer has increased the risk that australians already face from overexposure to. Researchers indicate that many of the effects of ozone depletion on human health tend to apply for animals, too. Thethe discoverydiscovery team who discovered the hole 1985.
Ashes can stay in the stratosphere for about two to five years, and within. Ozone does not absorb uva light uvb between 280 and 320 nanometers. Ozone in the stratospherea layer of the atmosphere between 15 and 50. The ozone layer prevents most ultraviolet uv and other highenergy radiation from penetrating to the earths surface but does. How does ozone depletion affect uv levels and life on earth. The latter phenomenon is referred to as the ozone hole. Since about the 1970s, there has been a decrease in total volume of the ozone in the ozone.
Ozone depletion, gradual thinning of earth s ozone layer in the upper atmosphere caused by the release of chemical compounds containing gaseous chlorine or bromine from industry and other human activities. There is a corresponding hole over the arctic that similarly appears in the spring, although in some years warmer winters there do not result in a major depletion of the ozone layer. New scientific evidence proves ozone depletion theory false. Depletion of this layer by ozone depleting substances ods will lead to higher uvb levels, which in turn will cause increased skin cancers and cataracts and potential damage to some marine organisms, plants, and plastics. But even a healthy, thick ozone layer doesnt prevent all uvb from reaching the earth. Ozone depletion describes the observed loss of ozone in the stratosphere over the past 50 years. 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. Ozone depletion cycles objective the objective of the exercise is to calculate the thermodynamic feasibility of several possible ozone depletion cycles. Get a printable copy pdf file of the complete article 926k. There have been several concerns about ozone depletion. Presentation on ozone depletion linkedin slideshare. The main ozonedepleting substances ods chlorofluorocarbons cfcs the most widely used ods, accounting for over 80% of total stratospheric ozone depletion. The danger and prevention of ozone layer depletion. New modelling techniques are helping to unravel the links between these two environmental issues, and to assess the implications of changes.
The antarctic hole now measures about 9 million square miles, nearly the. The ozonedepletion theory of global warming provides, for the first time, a clear, straightforward explanation for observations not easily explained by greenhousegas theory. Data from these instruments, although useful in learning about ozone, only tell us. Ozone layer depletion is one of the major environmental issues which is getting thinner day by day as a result of increasing pollution.
List of books and articles about ozone layer online. Joe farman, brian gardiner, and jonathan shanklin british atlantic survey research station, holly bay, antarctic coast in 1985, using satellites, balloons,in 1985, using satellites, balloons, and surface stations, a team ofand surface stations, a team of researchers. Scientific assessment of ozone depletion montreal protocol. Ozone is a particular gas present both in the earths upper atmosphere and at ground level. Ozone depletion occurs when the natural balance between the production and destruction of ozone in the stratosphere is tipped in favour of destruction. It can be found in small concentrations in the troposphere where it is considered a pollutant. Found in industrial solvents, drycleaning agents and hospital sterilants. The chlorofluorocarbon and the halons are potent ozone depletors. Procedure stratospheric ozone that protects the earth against harmful ultraviolet radiation is being depleted by the anthropogenic introduction of various gases into the atmosphere. This can be harmful to skin, and, thankfully, the ozone protects us from much of it. These ashes contain high concentration of bromine and chlorine. Twenty questions and answers about the ozone layer. This study showed that in the 1990s about 40% of the midlatitude ozone reduction in spring is caused by chemical ozone destruction during the arctic winter. There has been concern about anthropogenic chemical perturbations to the ozone layer for the past four decades.
Mar 21, 2020 ozone depletion, gradual thinning of earth s ozone layer in the upper atmosphere caused by the release of chemical compounds containing gaseous chlorine or bromine from industry and other human activities. Human activities like pollution and emissions already send lots of halogen gases into the stratosphere but, scientists have noted that halogens from volcanoes contain twice and thrice as many halogens that human activities even produce. Industries that manufacture things like insulating foams, solvents, soaps. The process of ozone depletion pennsylvania state university. Understanding that global warming is caused by ozone depletion, not greenhouse gases, has major implications for investments in energy. Full text full text is available as a scanned copy of the original print version. Research confirms that high levels of uv rays cause nonmelanoma skin cancer. Ozone depletion also explains much of the observed reduction in stratospheric and upper tropospheric temperatures. One of the primary functions of the ozone layer is to filter out the majority of solar uv radiation that can reach the earths surface. The ozone depletion theory predicts that there will be a 10 to 20 percent increase in the level of uvb radiation at the surface as a result of ozone depletion.
There are also springtime polar tropospheric ozone depletion. Less dramatic, still significant, depletion of ozone levels has been recorded around the globe. The main effect of ozone depletion is an increase in uvb rays reaching the earths surface causes. This timeline shows the chain of events leading to prediction of the ozone depletion phenomenon, recognition of its consequences, and eventual actions to avert a threatened disaster. The odp is the ratio of the impact on ozone of a chemical compared to the impact of a similar mass of cfc11.
The early literature in the 1970s first focused on perturbations by nitrogen oxide radicals from supersonic aircraft flying in the stratosphere 1,2 and later chlorine radicals from rocket exhaust and chlorofluorocarbons cfcs 3,4. Update on ozonedepleting substances odss and other gases of. Rivm report 481505011 technical report on stratospheric ozone depletion g. Pdf causes of ozone layer depletion and its effects on. Ozone depletion is the process of destruction of the ozone layer which can cause adverse effects on the living forms by many pollutants releases out from the vehicles, industries etc. The problems and causes associated with ozone depletion arise from human activities.
Twenty questions and answers about the ozone layer noaaesrl. The future evolution of ozone will depend on each of these gases, with n 2 o and co 2 probably playing the dominant roles as. This proves ozone depletion is a big issue that needs attention. The larger holes cause ozone to leak out at a faster rate than ozone is being created. Ozone depletion simple english wikipedia, the free encyclopedia. With less ozone in the atmosphere, more ultraviolet radiation strikes earth, causing more skin cancer, eye damage, and possible harm to crops. Jan 20, 2010 causes of ozone depletion there are two different types of ozone depletion, both are very similar. What is the impact of volcanic ash on the ozone layer. Essay ozone depletion is a serious problem presently facing the world. Technical report on stratospheric ozone depletion this report has been prepared by rivm, eftec, ntua and iiasa in association with tme and tno under contract with the environment directorategeneral of the european commission. Pdf ozone in the stratosphere is constantly being produced and destroyed by different. Causes of ozone depletion there are two different types of ozone depletion, both are very similar. These radiations can cause severe diseases in humans such as skin cancer, eye damage and genetic mutations etc 9. Ozone depletion simple english wikipedia, the free.
Stratospheric cooling creates a more favourable environ. Unfortunately, the ozone layer is currently under threat by manmade chemicals that remain in the atmosphere from their widespread use prior to being banned throughout most of the developed world in january 1996. 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. The ozone depletion phenomenon the ozone depletion. Ozone depletion definition ozone depletion is the term commonly used to describe the thinning of the ozone layer in the stratosphere. The ozone layer protects humans, animals, and plants from harmful ultraviolet rays. Find out what caused the ozone hole, and how the 1989 montreal protocol sought to put an end to ozone depletion. Pdf depletion of the ozone layer and its consequences. Consequently, the level of ozone protecting us from ultraviolet radiation decreases. For each ods, this page provides the compounds atmospheric lifetime, ozone depletion potential ozone depletion potentiala number that refers to the amount of ozone depletion caused by a substance. When volcanoes erupt, they produce massive clouds of ashes into the troposphere, and then they drift upward into the stratosphere the upper atmosphere layer where ozone gas protects humans from uv radiation. There, it will absorb almost all ultraviolet light which is harmful to many organisms. The initial step in the depletion of stratospheric ozone by human activities is the emission, at earths surface, of ozonedepleting gases containing chlorine and bromine. The ozone layer thus plays an important role by preventing the harmful uv radiations from penetrating into the earths lower atmosphere the troposphere.
Our powerpoint presentation about ozone depletion, its effects and its causes. Causes of ozone layer depletion and its effects on human. The antarctic hole now measures about 9 million square miles, nearly the size of north america. The ozone destroyed by manmade emissions is comparable or more than the amount destroyed by natural processes. Satellite data indicate a global reduction in ozone of about. The ozone layer is a region of the stratosphere containing ozone, or o3 gas.
This is the cause for the nearly 80% of the ozone depletion. The thinning of the ozone layer has increased the risk that australians already face from overexposure to uv radiation from an outdoor lifestyle. Since india already receives high doses of ultraviolet uvb radiation, and is at the threshold go to speak, effects of ozone layer depletion could he far more disastrous in india. In this picture we are seeing how the ozone layer is destroyed and the effects of that destruction. Following is the list of some of the main ozone depleting substances and the sources from where they are released.
These chemicals are found in cleaning agents, aerosols, insulating foam, and refrigerants. What are the principal steps in stratospheric ozone depletion caused by human activities. Each year since the late 1970s, much of the protective layer of stratospheric ozone above antarctica has disappeared during september, creating what is. The ozone layer prevents all uvc from reaching the earths surface. Ozone depletion is affecting the human health and environment negatively, as it allows the penetration of uv radiations to reach the earth. Causes of ozone depletion ozone depletion occurs when the natural balance between the production and destruction of stratospheric ozone is tipped in favour of destruction.
Ozone depletion in the stratosphere leads to an increase of uvb on ground with its harmful effects on health, ecosystems, aquatic system, materials etc. Ozone depletion free download as powerpoint presentation. The ozone layer is a deep blanket in the stratosphere made up of comparatively high concentration of the ozone. A global thinning of the ozone layer results as ozone rich air from the remaining ozone layer flows into the ozone poor. Ozone in the ozone layer is formed by the action of solar ultraviolet light on oxygen.
The ozone layer helps to protect life from harmful ultraviolet radiation. Depletion of the ozone layer has consequences on humans, animals, and plants. The first one has been a slow, but steady ozone depletion of 4% per decade of the earths. Dec 02, 2014 the main ozone depleting substances ods chlorofluorocarbons cfcs the most widely used ods, accounting for over 80% of total stratospheric ozone depletion. There, about 90% of atmospheric ozone is contained in the. Ozone depletion ozone depletion chlorofluorocarbon. This might seem like a large increase, unless one knows something about the geometry of the sun and the earth. As sciencedaily 2011 shows ozone hole linked to climate change all the way to the equator. Although natural phenomena can cause temporary ozone loss, chlorine and bromine released from manmade compounds such as cfcs are now accepted as the main cause of this. Fire extinguishers contain halons and methyl bromide in the form of pesticides can also be also a cause for the depletion. Nearly 60 plus countries met at montreal in 1987 to come. The main effect of ozone depletion is an increase in uvb rays reaching the earths surface.
Ozone depleting substances are the substances such as chlorofluorocarbons, halons, carbon tetrachloride, hydrofluorocarbons, etc. It is revealed that introduction of chloroflourocarbons cfcs in the environment is the most rated cause of said depiction. Jun 01, 2002 pdf of this article 607 kb john austin greg bodeker hamish struthers climate change is one problem, ozone depletion is another. Uv is also linked to cataracts a disease of the eye. It encompasses both a steady thinning of the ozone layer at midlatitudes and its catastrophic. Apr 18, 2019 the ozone layer helps to protect life from harmful ultraviolet radiation.
It contains some videos and gif at thte end from an external source. The term ozone depletion can refer to a number of distinct, but related phenomena. About 2 billion years ago as photo synthesising organisms emitted oxygen o2, a waste gas ozoneo3 gradually began to form within the atmosphere 1. As a result of its chemical composition, ozone is regarded as a special type of oxygen as it contains three oxygen molecules o3 as opposed to the usual two oxygen molecules o2.
Ozone is ozone is a form of oxygen with 3 oxygen atoms o3. The exposure to these radiations is severely affecting all life forms on earth. Project report on ozone depletion environmental pollution. This means the potential of depleting the ozone layer is higher with volcanic smoke. Altitude kilometers ozone concentration ozone layer ozone increases from pollution stratospheric ozone tropospheric ozone o. Stratospheric ozone depletion, ultraviolet radiation and.
The most harmful effects of ozone depletion greentumble. Ozone is a gas that is present in the ozone layer in the stratosphere of the earth. The effects of anthropogenic emissions of nitrous oxide n 2 o, carbon dioxide co 2, methane ch 4 and the halocarbons on stratospheric ozone o 3 over the twentieth and twentyfirst centuries are isolated using a chemical model of the stratosphere. Causes, effects and solutions of ozone layer depletion. Evolution of policy responses to stratospheric ozone depletion. This typically results from higher uv levels reaching us on earth.
The ozone depletion phenomenon the national academies press. To protect the ozone layer ozone layerthe region of the stratosphere containing the bulk of atmospheric ozone. Perhaps the two most debated environmental issues in recent years have been climate change and ozone. What are the causes and effects of ozone depletion. Protecting the ozone layer department of the environment. Additionally, it plays a major role in malignant melanoma development. The hole in the ozone layer above antarctica has more farreaching consequences than previously assumed. The ozone layer lies about 15 40 km in altitude, although this height varies with latitude. Thus, ozone layer depletion has become a major concern among the environmentalists. Ozonedepleting substances ozone layer protection us epa. Ozone depletion consists of two related events observed since the late 1970s. Ozone is highly corrosive and toxic and is used as a disinfectant. Solution on ozone layer depletion september 16 was voted the world ozone day in the year 1994 by the united nations general assembly. Ozone depletion ozone depletion chlorofluorocarbon free.
The ozone layer is a belt of the naturallyoccuring gas ozone that sits at an altitude of between 15 and 30 kilometers above the earth. The ozone layer lies approximately 1540 kilometers 1025 miles above the earths surface, in the stratosphere. One of the main reasons for the widespread concern about depletion of the ozone layer is the anticipated increase in the amounts of ultraviolet radiation received at the surface of the earth and the effect of this on human health and on the environment. Ozone depletion facts and information national geographic. Ozone depletion ozone layer depletion, is simply the wearing out reduction of the amount of ozone in the stratosphere.
Used as coolants in refrigerators, freezers and air conditioners in buildings and cars manufactured before 1995. It is rich in examples of how basic research often contributes to unanticipated outcomes of immense societal benefit. There are important effects of changes in the intensity of solar uv radiation resulting from stratospheric ozone depletion, particularly uvb. Since about the 1970s, there has been a decrease in total volume of the ozone in the ozone layer, of about 4%, per decade. Hence, we should be aware and actions must be taken to ensure that ozone layer is not destroyed. This timeline highlights the average area of the ozone hole between september 7th and october th as observed by nasa spacedbased instruments see colored bars and scale. One of the main reasons for the widespread concern about depletion of the ozone layer is the anticipated increase in the amounts of ultraviolet. The thinning is most pronounced in the polar regions, especially over antarctica. Ozone depletion over india 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. Ozone layer depletion essay sample new york essays.
Cfcs may trap heat and thus contribute to the global warming. The loss in this region is commonly called the ozone hole be cause the ozone depletion is so large and localized. Unlike pollution, which has many types and causes, ozone depletion has been pinned down to one major human activity. Like an infection that grows more and more virulent, the continentsize hole in earths ozone layer keeps getting bigger and bigger. Money and time are being spent on ozone repair, but the problem still exists. Ozone layer depletion cause, effects, and solutions. The ozonedepletion theory of global warming provides, for the first time, a clear, straightforward explanation for observations not easily explained by. There, about 90% of atmospheric ozone is contained in the ozone layer, which shields us from harmful ultraviolet radiation from the sun. This article has been cited by other articles in pmc. Ozone depletion and climate change environment canada.
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