There, it will absorb almost all ultraviolet light which is harmful to many organisms. Ozone layer and the formation of the ozone hole aa. The thinning is most pronounced in the polar regions, especially over antarctica. Ozone depletion free download as powerpoint presentation. 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. Learn more about the process, causes, and effects of ozone layer depletion. However, various factors have led to the depletion and damage of this protective layer. The term ozone depletion can refer to a number of distinct, but related phenomena. The ozone layer or ozone shield is a region of earths stratosphere that absorbs most of the suns ultraviolet radiation. Ozone layer depletion ozone layer depletion is the gradual thinning of the earths ozone layer in the upper atmosphere caused due tho release of chemical compounds containing gaseous bromine or chlorine from industries or other human activities. Ozone depletion simple english wikipedia, the free encyclopedia. This quick video discusses the role of the ozone layer and how cfcs can cause ozone depletion. What are the principal steps in stratospheric ozone depletion caused by human activities.
The troposphere extends from the surface up to about 10 km in altitude, although this height varies with latitude. Stratospheric ozone protection awards since 1990, epa has recognized outstanding achievement in ozone layer protection. Jul 02, 2015 this quick video discusses the role of the ozone layer and how cfcs can cause ozone depletion. The clo molecules combine with each other, forming a com. Ozone o3 is formed by the combination of three oxygen atoms. Pdf depletion of the ozone layer and its consequences.
What is ozone, how is it formed, and where is it in the atmosphere. The causes, mechanism and bioeffects of ozone layer depletion on humans were addressed. At the same time, however, the regime for the protection. Ozone absorbs a band of ultraviolet radiation called uvb. 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. If interested, you can purchase this powerpoint from my online store. Pdf atmospheric ozone and its depletion researchgate. If interested, you can purchase this powerpoint from. The ozone layer is a belt of the naturallyoccuring gas ozone that sits.
Pdf causes of ozone layer depletion and its effects on. The ozone layer is not really a layer at all, but has become known as such because most ozone particles are scattered between 19 and 30 kilometers 12 to 30 miles up in the earths atmosphere, in a region called the stratosphere. Scientists have calculated that if the ozone layer was brought down to sea level it would be 3 mm thick, while in the antarctic the ozone can be as low as 1 mm thick. Causes of ozone layer depletion and its effects on human. Nearly 500 organizations, teams, and individuals from 40 countries have received stratospheric ozone protection awards for their exceptional leadership, personal dedication, and technical achievements. The chlorofluorocarbon and the halons are potent ozone depletors. The term ozone depletion means more than just the natural destruction of ozone, it means that ozone loss is exceeding ozone creation.
Bromine can also act as a catalyst to destroy stratospheric ozone. Let us have a detailed look at the various causes and effects of ozone layer depletion. The thinning of the ozone layer has increased the risk that australians already face from overexposure to. Formation and depletion effect of the montreal protocol on stratospheric cl sunlight incident on earth is very roughly. The initial step in the depletion of stratospheric ozone by human activities is the emission of ozonedepleting. The use of cfcs not only destroys the ozone layer but also leads to global warming. The ozone layer is mainly found in the lower portion of the stratosphere. It not only affects human health but it is also a threat to plants and other living organisms. Ozone in the stratospherea layer of the atmosphere between 15 and 50 kilometers 10 and. Within the stratosphere, the ozone layer is the portion that contains the highest. The earths ozone layer is mainly found in the lower portion of the stratosphere from approximately 20 to 30. 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. 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. Apr 18, 2019 the ozone layer helps to protect life from harmful ultraviolet radiation.
The earths ozone layer ozone layerthe region of the stratosphere containing the bulk of atmospheric ozone. Sunlight drives both ozone formation and destruction and this. This ozone layer sustains life on the earth by absorbing a great deal of uv ultra violet light radiating out of sun. Peak depletion occurs in early october when ozone is often completely destroyed.
Ozone depletion ozone depletion chlorofluorocarbon. Most ozone is found in the stratosphere upper part of the atmosphere, more than 10 to 16 kms from the surface of the earth. Depletion of stratospheric ozone o3, as commonly known as the hole in the ozone layer, is an issue of international concern. Therefore, the economic activities of the human have resulted in depletion of the ozone layer and increasing the global warming on the earth and it accounts to 82% of the total ozone layer depletion and global warming desmet and rossihansberg 2015. The effort to protect the earths ozone layer has been the first occasion where. After a decade of relentless enlargement and deepening, it seems that ozone layer depletion might eventually be curbed, and precfc levels of the ozone layer reached by the midtwentyfirst century. O 3 depletion leads to the entry of more uv radiation into the troposphere.
In the lower atmosphere troposphere, ozone is formed in a different set of chemical reactions involv. Pdf ozone o 3 is a stratospheric layer that plays important role in providing support to humans for. Mar 21, 2020 ozone depletion, gradual thinning of earths ozone layer in the upper atmosphere caused by the release of chemical compounds containing gaseous chlorine or bromine from industry and other human activities. Basic ozone layer science ozone layer protection us epa. Ground ozone concentration is lower in polar and equatorial regions. Causes and effects of ozone layer depletion that are. Ozone is good in the stratosphere because it absorbs all of the most energetic ultraviolet radiation uvc, most of the uvb radiation and some of the least energetic uv radiation uva. In this picture we are seeing how the ozone layer is destroyed and the effects of that destruction. Severe depletion of the antarctic ozone layer was first reported in the mid1980s. The thinning of the ozone layer has increased the risk that australians already face from overexposure to uv radiation from an outdoor lifestyle.
Project ozone layer depletion pdf the stratospheric ozone layer forms a thin shield in the upper atmosphere, protecting life on earth from. The level from which it extends outward varies with latitude. The arctic ozone layer, how the arctic ozone layer is responding. It contains high concentration of ozone o 3 in relation to other parts of the atmosphere, although still small in relation to other gases in the stratosphere. We cant make enough ozone to replace whats been destroyed, but provided that we stop producing ozonedepleting substances, natural. Uv radiations are very harmful and can cause health issues such as skin cancer, ageing of skin, cataract, sunburn, etc.
The ozone hole is shown in purple above the antarctic on sept. Project report on ozone depletion environmental pollution. Ozone layer depletion is one of the major environmental issues which is getting thinner day by day as a result of increasing pollution. The ozone layer helps to protect life from harmful ultraviolet radiation.
Ozone layer depletion, is simply the wearing out reduction of the amount of ozone in the stratosphere. These models work by combining satellite measurements of chemical. 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. Does depletion of the ozone layer increase groundlevel ultraviolet radiation. Ozone depletion, gradual thinning of earths ozone layer in the upper atmosphere caused by the release of chemical compounds containing gaseous chlorine or bromine from industry and other human activities. To the point where a seasonal hole in the ozone layer began to appear above the antarctic. The process of ozone depletion pennsylvania state university. They are separate problems, but, as has been seen, there are links between each. Antarctic ozone depletion is seasonal, occurring primarily in late winter and early spring augustnovember. Find out what caused the ozone hole, and how the 1989 montreal protocol sought to put an end to ozone depletion. Twenty questions and answers about the ozone layer. The ozone layer is responsible for absorbing harmful ultraviolet rays, and preventing them from entering the earths atmosphere. The main purpose in our website is to inform students and adults about the ozone layer and ozone depletion. The ozone layer refers to a region of earths stratosphere that absorbs most of the suns uv radiation.
Unlike pollution, which has many types and causes, ozone depletion has. The ozone layer in antarctica oceanwide expeditions. The earths atmosphere is composed of several layers. The reason behind ozone layer depletion is mainly due to the extensive use of ozonedepleting substances ods. Case study depletion of ozone in the atmosphere the work of g. Cfcs nonflammable nontoxic trap heat good insulators.
The problem is worsened as cfcs are a primary cause of the damage and they remain in the stratosphere for up to 100 years. B dobson inferred correctly that the cause of the warm stratosphere was heating by the absorption of ultraviolet solar radiation by ozone, and he set out to. 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. Hegglin coordinating lead authors this document answers some of the most commonly asked questions about the ozone layer. Ozone is formed throughout the atmosphere in multistep chemical processes that require sunlight.
Putting additional ozonedestroying compounds such as cfcs into the atmosphere is like increasing the size of. The natural distribution of ozone around the earth is. Ozone depletion is allowing the uv radiation to earth surface. Nearly 90% of earths ozone is in the stratosphere and referred to as the ozone layer. When these ozonedepleting substances ods break down in the. The atmosphere is mostly transparent to the visible except for scatter. When present together in the stratosphere, chlorine cl and ozone quickly react to produce chlorine oxide. Ozone layer depletion article about ozone layer depletion. Our powerpoint presentation about ozone depletion, its effects and its causes.
Chlorofluorocarbons ozone depletion occurs when the natural balance between the production and destruction of stratospheric ozone is disturbed. The ozone layer lies approximately 1540 kilometers 1025 miles above the earths surface, in the stratosphere. These o atoms combine with molecular form of oxygen to form ozone o3. Protecting the ozone layer and reducing global warming undp. Arctic ozone depletion will continue to be of concern in the coming decades as a result of the. World meteorological organization united nations environment programme. A region of the considerable ozone depletion is named an ozone hole. The use of cfc s is one of the main reasons for the depletion of the layer. The maps were produced with data collected by statellite istruments, including the ozone monitoring instrument on the aura satellite. This website provides key information on how ozone depletion started, what is being done to prevent damage to our ozone and what effects will occur if depletion continues. Ozone depletion consists of two related events observed since the late 1970s. The subtropical ground ozone concentration in northern hemisphere is twice the corresponding region in southern hemisphere 5. Calculations of eesc combine the amounts of chlorine and bro.
Ozone depletion facts and information national geographic. Ozonedepleting substances and their impact on the arctic ozone layer. It contains high concentrations of ozone o3 relative to other parts of the atmosphere. Thus, under natural conditions, combining screening of and has protected. Ozone layer depletion cause, effects, and solutions biology. Ozone is a gas that is present in the ozone layer in the stratosphere of the earth.
It is revealed that introduction of chloroflourocarbons cfcs in the environment is the most rated cause of said depiction. Unlike pollution, which has many types and causes, ozone depletion has been pinned down to one major human activity. An international consensus about the causes and effects of ozone depletion has emerged. Twenty questions and answers about the ozone layer noaa esrl. In fact, global warming, acid rain, ozone layer depletion, and groundlevel ozone pollution all pose a serious threat to the quality of life on earth.
How severe is the depletion of the antarctic ozone layer. Effects and measures to protect ozone layer depletion. B dobson and other scientists in measuring concentrations of chloride and ozone in the atmosphere g. All of us are aware of how the concern related to depletion of ozone layer and the ozone hole, which also led to the ban of. Causes of ozone depletion source impact cfcs the increase in the size of the hole in the ozone layer is directly linked to increased production of cfcs since the 1950s in aerosols, plastic foam, fast food packaging and.
The term ozone layer being very popular in the mass media is misleading, since it implies a distinct. The term ozone depletion means that the destruction of o3 exceeds the creation of o3. The lowest layer, the troposphere tropospherethe region of the atmosphere closest to the earth. Timeline of stratospheric ozone depletion and observations. Inexpensive light extremely stable, inert traditional refrigerants ammonia, sulfur dioxide, methyl chloride highly volatile caustic and toxic remove heat through vaporization of liquefied gas only adequate as refrigerants expensive heavy transport, storage. Recently the depleted ozone concentration was detected above arctic, western europe. If the use of cfcs and other ozone destroying chemicals are banned, it is hoped that ozone depletion may be reduced.
At the end of 20, 258 projects have been committed for an. Another most feared aspect of pollution is depletion of ozone layer of the stratosphere. Jan 10, 2011 an international consensus about the causes and effects of ozone depletion has emerged. Ozone in the stratosphere is being depleted by a variety of humanmade gases with a hole forming over antarctica. Our media contains interviews, and videos that give a visual aspect to the importance of our ozone. Ozone is unstable molecule and maintains a balance between its formation. Protecting the ozone layer department of the environment. The ozone layer was discovered in 19 by the french physicists charles fabry and henri buisson.
709 639 1084 930 751 467 1290 253 788 764 296 1164 1350 734 18 1137 1512 377 1556 719 211 121 509 452 947 983 879 967 1239