The ozone destroyed by manmade emissions is comparable or more than the amount destroyed by natural processes. 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. The larger holes cause ozone to leak out at a faster rate than ozone is being created. The loss in this region is commonly called the ozone hole be cause the ozone depletion is so large and localized. It contains some videos and gif at thte end from an external source. The latter phenomenon is referred to as the ozone hole.
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. The thinning of the ozone layer has increased the risk that australians already face from overexposure to. Ozone depletion consists of two related events observed since the late 1970s. Uv is also linked to cataracts a disease of the eye. The ozone layer helps to protect life from harmful ultraviolet radiation. Stratospheric ozone depletion due to nitrous oxide.
In this picture we are seeing how the ozone layer is destroyed and the effects of that destruction. It is rich in examples of how basic research often contributes to unanticipated outcomes of immense societal benefit. Pdf causes of ozone layer depletion and its effects on. 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. 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. Thus, ozone layer depletion has become a major concern among the environmentalists.
The ozone depletion phenomenon the ozone depletion. Ozone is a particular gas present both in the earths upper atmosphere and at ground level. Ozone layer depletion is one of the major environmental issues which is getting thinner day by day as a result of increasing pollution. There are important effects of changes in the intensity of solar uv radiation resulting from stratospheric ozone depletion, particularly uvb. These chemicals are found in cleaning agents, aerosols, insulating foam, and refrigerants. The most harmful effects of ozone depletion greentumble. Ozone depletion and climate change environment canada.
Ozone does not absorb uva light uvb between 280 and 320 nanometers. 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. Perhaps the two most debated environmental issues in recent years have been climate change and ozone. 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. This is the cause for the nearly 80% of the ozone depletion. Hence, we should be aware and actions must be taken to ensure that ozone layer is not destroyed. The ozonedepletion theory of global warming provides, for the first time, a clear, straightforward explanation for observations not easily explained by. Project report on ozone depletion environmental pollution. Causes, effects and solutions of ozone layer depletion. The main effect of ozone depletion is an increase in uvb rays reaching the earths surface. 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. 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.
The process of ozone depletion pennsylvania state university. Since about the 1970s, there has been a decrease in total volume of the ozone in the ozone. Ozone depletion is primarily caused by human activities. Ozone depletion is allowing the uv radiation to earth surface. Ozone depleting substances are the substances such as chlorofluorocarbons, halons, carbon tetrachloride, hydrofluorocarbons, etc. Ozone depletion describes the observed loss of ozone in the stratosphere over the past 50 years.
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. To protect the ozone layer ozone layerthe region of the stratosphere containing the bulk of atmospheric ozone. About 2 billion years ago as photo synthesising organisms emitted oxygen o2, a waste gas ozoneo3 gradually began to form within the atmosphere 1. Unlike pollution, which has many types and causes, ozone depletion has been pinned down to one major human activity. Our powerpoint presentation about ozone depletion, its effects and its causes. Used as coolants in refrigerators, freezers and air conditioners in buildings and cars manufactured before 1995. Ozone is highly corrosive and toxic and is used as a disinfectant. Ozone is a gas that is present in the ozone layer in the stratosphere of the earth. Ozone depletion facts and information national geographic. Ozonedepleting substances ozone layer protection us epa. Cfcs may trap heat and thus contribute to the global warming. Ozone depletion ozone layer depletion, is simply the wearing out reduction of the amount of ozone in the stratosphere. 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. The ozone layer is a deep blanket in the stratosphere made up of comparatively high concentration of the ozone.
Industries that manufacture things like insulating foams, solvents, soaps. 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. 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. The ozone layer lies about 15 40 km in altitude, although this height varies with latitude. The main ozonedepleting substances ods chlorofluorocarbons cfcs the most widely used ods, accounting for over 80% of total stratospheric ozone depletion. 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. Solution on ozone layer depletion september 16 was voted the world ozone day in the year 1994 by the united nations general assembly. 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 term ozone depletion can refer to a number of distinct, but related phenomena. 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. 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. 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.
Presentation on ozone depletion linkedin slideshare. Full text full text is available as a scanned copy of the original print version. Ozone depletion ozone depletion chlorofluorocarbon free. Fire extinguishers contain halons and methyl bromide in the form of pesticides can also be also a cause for the depletion. This might seem like a large increase, unless one knows something about the geometry of the sun and the earth. 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. 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.
These radiations can cause severe diseases in humans such as skin cancer, eye damage and genetic mutations etc 9. The problems and causes associated with ozone depletion arise from human activities. There are also springtime polar tropospheric ozone depletion. This proves ozone depletion is a big issue that needs. Like an infection that grows more and more virulent, the continentsize hole in earths ozone layer keeps getting bigger and bigger.
Scientific assessment of ozone depletion montreal protocol. How does ozone depletion affect uv levels and life on earth. List of books and articles about ozone layer online. Twenty questions and answers about the ozone layer. Ashes can stay in the stratosphere for about two to five years, and within. It encompasses both a steady thinning of the ozone layer at midlatitudes and its catastrophic. Nearly 60 plus countries met at montreal in 1987 to come. The antarctic hole now measures about 9 million square miles, nearly the. 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. The danger and prevention of ozone layer depletion. Less dramatic, still significant, depletion of ozone levels has been recorded around the globe. Ozone is ozone is a form of oxygen with 3 oxygen atoms o3. What is the impact of volcanic ash on the ozone layer.
The main effect of ozone depletion is an increase in uvb rays reaching the earths surface causes. The ozone layer protects humans, animals, and plants from harmful ultraviolet rays. The ozone layer prevents most ultraviolet uv and other highenergy radiation from penetrating to the earths surface but does. Causes of ozone depletion there are two different types of ozone depletion, both are very similar. 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. Ozone depletion has also been detected outside the antarctic. The ozone layer lies approximately 1540 kilometers 1025 miles above the earths surface, in the stratosphere. Essay ozone depletion is a serious problem presently facing the world. 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.
Data from these instruments, although useful in learning about ozone, only tell us. Money and time are being spent on ozone repair, but the problem still exists. Twenty questions and answers about the ozone layer noaaesrl. There, about 90% of atmospheric ozone is contained in the ozone layer, which shields us from harmful ultraviolet radiation from the sun. 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. Ozone depletion is affecting the human health and environment negatively, as it allows the penetration of uv radiations to reach the earth. Jun 01, 2002 pdf of this article 607 kb john austin greg bodeker hamish struthers climate change is one problem, ozone depletion is another. Procedure stratospheric ozone that protects the earth against harmful ultraviolet radiation is being depleted by the anthropogenic introduction of various gases into the atmosphere. Depletion of the ozone layer has consequences on humans, animals, and plants. Thethe discoverydiscovery team who discovered the hole 1985.
New scientific evidence proves ozone depletion theory false. The ozone layer is a region of the stratosphere containing ozone, or o3 gas. 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. There, it will absorb almost all ultraviolet light which is harmful to many organisms. As sciencedaily 2011 shows ozone hole linked to climate change all the way to the equator. 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. The ozone layer prevents all uvc from reaching the earths surface. Ozone in the stratospherea layer of the atmosphere between 15 and 50. Pdf ozone in the stratosphere is constantly being produced and destroyed by different. The ozonedepletion theory of global warming provides, for the first time, a clear, straightforward explanation for observations not easily explained by greenhousegas theory. 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.
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. 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. Consequently, the level of ozone protecting us from ultraviolet radiation decreases. The thinning is most pronounced in the polar regions, especially over antarctica. What are the causes and effects of ozone depletion. Ozone depletion simple english wikipedia, the free. A global thinning of the ozone layer results as ozone rich air from the remaining ozone layer flows into the ozone poor. Get a printable copy pdf file of the complete article 926k. Each year since the late 1970s, much of the protective layer of stratospheric ozone above antarctica has disappeared during september, creating what is.
What are the principal steps in stratospheric ozone depletion caused by human activities. Ozone depletion ozone depletion chlorofluorocarbon. The ozone depletion phenomenon the national academies press. Since about the 1970s, there has been a decrease in total volume of the ozone in the ozone layer, of about 4%, per decade. 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 has been concern about anthropogenic chemical perturbations to the ozone layer for the past four decades. This means the potential of depleting the ozone layer is higher with volcanic smoke. The ozone layer thus plays an important role by preventing the harmful uv radiations from penetrating into the earths lower atmosphere the troposphere. The antarctic hole now measures about 9 million square miles, nearly the size of north america. Researchers indicate that many of the effects of ozone depletion on human health tend to apply for animals, too. Protecting the ozone layer department of the environment. With less ozone in the atmosphere, more ultraviolet radiation strikes earth, causing more skin cancer, eye damage, and possible harm to crops. Effects of ozone depletion ozone depletion is affecting the human health and environment negatively, as it allows the penetration of uv radiations to reach the earth. This article has been cited by other articles in pmc.
These ashes contain high concentration of bromine and chlorine. Stratospheric ozone depletion, ultraviolet radiation and. Stratospheric cooling creates a more favourable environ. The hole in the ozone layer above antarctica has more farreaching consequences than previously assumed. Find out what caused the ozone hole, and how the 1989 montreal protocol sought to put an end to ozone depletion. Ozone depletion occurs when the natural balance between the production and destruction of ozone in the stratosphere is tipped in favour of destruction. Ozone depletion also explains much of the observed reduction in stratospheric and upper tropospheric temperatures. 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. 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. Update on ozonedepleting substances odss and other gases of. Evolution of policy responses to stratospheric ozone depletion. Apr 18, 2019 the ozone layer helps to protect life from harmful ultraviolet radiation.
Rivm report 481505011 technical report on stratospheric ozone depletion g. This typically results from higher uv levels reaching us on earth. New modelling techniques are helping to unravel the links between these two environmental issues, and to assess the implications of changes. 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. This can be harmful to skin, and, thankfully, the ozone protects us from much of it. Understanding that global warming is caused by ozone depletion, not greenhouse gases, has major implications for investments in energy. Ozone depletion cycles objective the objective of the exercise is to calculate the thermodynamic feasibility of several possible ozone depletion cycles. Ozone depletion in the stratosphere leads to an increase of uvb on ground with its harmful effects on health, ecosystems, aquatic system, materials etc.
It is revealed that introduction of chloroflourocarbons cfcs in the environment is the most rated cause of said depiction. Additionally, it plays a major role in malignant melanoma development. But even a healthy, thick ozone layer doesnt prevent all uvb from reaching the earth. Ozone layer depletion essay sample new york essays. Jan 20, 2010 causes of ozone depletion there are two different types of ozone depletion, both are very similar. Ozone depletion simple english wikipedia, the free encyclopedia. The first one has been a slow, but steady ozone depletion of 4% per decade of the earths. The odp is the ratio of the impact on ozone of a chemical compared to the impact of a similar mass of cfc11. The exposure to these radiations is severely affecting all life forms on earth. Causes of ozone layer depletion and its effects on human. Altitude kilometers ozone concentration ozone layer ozone increases from pollution stratospheric ozone tropospheric ozone o. The latest ozone layer depletion news is included at the foot of the page. 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. There, about 90% of atmospheric ozone is contained in the.
This proves ozone depletion is a big issue that needs attention. 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. It can be found in small concentrations in the troposphere where it is considered a pollutant. One of the main reasons for the widespread concern about depletion of the ozone layer is the anticipated increase in the amounts of ultraviolet. There have been several concerns about ozone depletion. Ozone depletion definition ozone depletion is the term commonly used to describe the thinning of the ozone layer in the stratosphere. The chlorofluorocarbon and the halons are potent ozone depletors. Satellite data indicate a global reduction in ozone of about.
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