Ozone depletion consists of two related events observed since the late 1970s. Progress report 2003 united nations environment programme, environmental e. By rogelio maduro coauthor of the book the holes in the ozone scare, 1993. The main effect of ozone depletion is an increase in uvb raysreaching the earths surface. Depletion of ozone layer is also causing the problem of food shortage to humans. The ozone depletion process replacing lost ozone in the stratosphere the idea is sometimes put forth that humans could compensate for lost global stratospheric ozone by replacing it. 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. Mechanisms of ozone depletion hindi environmental issues for pre medical exams. Project report on ozone depletion environmental pollution. Ozone layer the ozone layer is basically naturally occurring gas in the region of stratosphere where ozone particles are accumulated 2. Next, you will use a mathematical program called mathematica to investigate the kinetics of ozone reactions in the atmosphere.
Lets have a look at some of the solutions to ozone layer depletion. Find out what caused the ozone hole, and how the 1989 montreal protocol sought to put an end to ozone depletion. The use of cfcs not only destroys the ozone layer but also leads to global warming. Ozone o3 is produced in the stratosphere by the intense solar radiation causing photodissociation of. It was first identified in 1970s due to the advent of supersonic aircraft, which fly in the lower stratosphere and emit nitrogen oxides. Ozone layer and causes, effects and solutions to ozone depletion ozone layer depletion is the destruction of ozone gas of upper atmospheric layer stratosphere, caused by substances formed from breakdown of ozone depleting substances ods the ozone layer plays an ultimately significant role in absorbing ultraviolet radiation that are 3. Ground ozone concentration is lower in polar and equatorial regions. Experts blame ozonelayer depletion on manmade chem.
Pdf there are many situations where human activities have significant effects on the. Timeline of stratospheric ozone depletion and observations. List of books and articles about ozone layer online. 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 layer depletion cause, effects, and solutions. Acid rain and ozone layer depletion download ebook pdf. The ozone layer protects living things from harmful ultraviolet rays from the sun. Ozone layer depletion, its causes and its effects free download as powerpoint presentation. The ozone layer refers to a region of earths stratosphere that absorbs most of the suns uv radiation. How do the different mech anisms of ozone depletion compare.
Ozone blocks ultraviolet radiation ozone depleting substances are. These gaseous pollutants react with the ozone to produce oxygen by which the net result is the depletion of ozone. Protecting the ozone layer department of the environment. Evidence for this mechanism comes from a variety of sources.
Ozone depletion in canada is usually greatest in the late winter and early spring. For instance, ground and in situ measurements show that maximum ozone depletion coincides with. This exercise investigates the kinetics of ozone formation and depletion in the atmosphere. This radiation could have seriously damaging effects on germinating crops and on the photoplankton of the oceans. This is not really a hole through the ozone layer, but rather a large area of the stratosphere with extremely low amounts of ozone. 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. Cfcs destroy the ozone in the stratosphere 15 20 km above the earths surface ozone concentrations are measure in dobsen units, 1 dobsen unit represents 1 molecule of o 3 for every 1 billion air molecules ozone loss is greatest over antarctica where the ozone depletion has been recorded and is commonly referred to as the ozone hole. Ozone o3 is a stratospheric layer that plays important role in providing support to humans for their survival. What is the impact of volcanic ash on the ozone layer. The most harmful effects of ozone depletion greentumble. The envelope of air or different types of gases surrounding the earth is known as atmosphere. 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. Is depletion of the ozone layer the principal cause of climate change. Massive global ozone loss predicted following regional.
Ozone could be manufactured, stored, transported to the stratosphere, and released in depleted regions. Ozone layer depletion article about ozone layer depletion. The earths stratospheric ozone layer plays a critical role in absorbing ultraviolet radiation emitted by the sun. Is depletion of the ozone layer the principal cause of. First you will use excel to determine the concentration profile of ozone in the atmosphere. It is revealed that introduction of chloroflourocarbons cfcs in the environment is the most rated causeof said depiction. These chemicals are found in cleaning agents, aerosols, insulating foam, and refrigerants. Apr 18, 2019 the ozone layer helps to protect life from harmful ultraviolet radiation. In this lesson, students will develop an explanation for the consequences of ozone depletion on earth by planning and carrying out an investigation. Now i am going to tell you what are the adverse effects caused by the depletion of the ozone layer ozone which accounts for only 3 parts in ten millions of earths atmosphere, plays several crucial roles in the radiation balance of the planet. Ozone is a gas that is present in the ozone layer in the stratosphere of the earth. Ozone layer depletion cause, effects, and solutions biology. Causes, effects and solutions of ozone layer depletion.
The antarctic ozone hole, as it came to be known, made depletion of. The subtropical ground ozone concentration in northern hemisphere is twice the corresponding region in southern hemisphere 5. Near the ground, ozone forming as a result of chemical reactions involving traffic pollution and sunlight may cause a number of respiratory problems, particularly for young children. The ozone layer is mainly found in the lower portion of the stratosphere, about 20 to 30 km 12 to 19 miles above the earth, though the thickness varies seasonally and geographically. In fact whole world is vulnerable to its after affects. Most ozone is found in the stratosphere upper part of the atmosphere, more than 10 to 16 kms from the surface of the earth.
In the last thirty years, it has been discovered that stratospheric ozone is depleting as a result of anthropogenic pollutants. Effects of ozone depletion for humans and the environment. As it is a framework convention, it only establishes a framework on. There, it will absorb almost all ultraviolet light which is harmful to many organisms. Ozone layer is an international treaty designed to protect the ozone layerby phasing out the production of numerous substances that are responsible forozone depletion. The ozone layer the buildup of oxygen in the atmosphere led to the natural formation of the ozone layer. One chlorine can destroy 100,000 molecules of ozone. Causes of ozone layer depletion and its effects on human. The level from which it extends outward varies with latitude. Humans have introduced gases and chemicals into the atmosphere that have rapidly depleted the ozone layer in the last century. The vienna convention for the protection of the ozone layer vc was adopted in 1985 and came into force on 22 september 1988. No, ozone depletion itself is not the principal cause of climate change. The treaty is structured around several groups of halogenated hydrocarbonsthat deplete stratospheric. 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.
The thinning is most pronounced in the polar regions, especially over antarctica. Update on ozonedepleting substances odss and other gases of. Scribd is the worlds largest social reading and publishing site. The earths ozone layer is mainly found in the lower portion of the stratosphere from approximately 20 to 30. Explain the role of nox in the generation of tropospheric ozone. The ozone layer is mainly found in the lower portion of the stratosphere.
The ozone layer was discovered in 19 by the french physicists charles fabry and henri buisson. The troposphere extends from the surface of the earth upto 12 km and stratosphere extends upto about 50 km from the surface of the. Ozone ozone is a simple molecule of three oxygen atoms and it is present in the two lowest layers of the atmosphere troposphere and stratosphere. Various anthropogenic activities such as emissions of cfcs, hcfcs and other organohalogens lead to the depletion of 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.
While several substances were addressed, chcs and hcfcs were the main ones that the international. This ozone layer sustains life on the earth by absorbing a great deal of uv ultra violet light radiating out of sun. Scientific assessment of ozone depletion montreal protocol unep. It contains high concentrations of ozone o3 relative to other parts of the atmosphere. The ozone depletion resulted in secondary production of an ozone layer near the ground terrestrial ozone layer, which is responsible for adverse effects on plants. One example of ozone depletion is the annual ozone hole over antarctica that has occurred during the antarctic spring since the early 1980s. Environmental studies ozone depletion tutorialspoint. The ozone depleting effect of refrigerants is important, because the ozone layer filters out ultraviolet uv radiation, which might otherwise reach the surface of the earth.
The ozone layer is responsible for absorbing harmful ultraviolet rays, and preventing them from entering the earths atmosphere. Pdf causes of ozone layer depletion and its effects on. Case study on ozone layer ozone depletion chlorofluorocarbon. Ozone layer and the formation of the ozone hole aa. 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 detailed mechanism by which the polar ozone holes form. This depletion makes humans more vulnerable to the uvb rays which are known to cause skin cancer as well as other genetic deformities.
The term ozone depletion can refer to a number of distinct, but related phenomena. Ozone depletion is largely a result of manmade substances. Implications of ozone depletion and the montreal protocol 20 questions. Nearly 500 organizations, teams, and individuals from 40 countries have received stratospheric ozone protection awards for their exceptional leadership, personal dedication, and technical achievements.
Our results point to previously unrecognized mechanisms for stratospheric ozone depletion. They are separate problems, but, as has been seen, there are links between each. 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. Ozone depletion refers to the wearing out or reduction of the amount of ozone in the stratosphere. Even the proponents of humaninduced ozone depletion are starting to realize that the thinning of the ozone layer is a natural phenomenon that just waxes and wanes. New scientific evidence continues to demonstrate that the ozone depletion models and the resulting ban on cfcs are based on a big lie. Ozone layer depletion causes increased uv radiation levels at the earths surface, which is damaging to human health. The ozone layer over southern canada has thinned by an average of about 7% since the 1980s. The main cause of ozone depletion and the ozone hole is manufactured chemicals. Pdf depletion of the ozone layer and its consequences. There are many situations where human activities have. Stratospheric ozone absorbs ultraviolet solar radiation, and the absorbed energy heats the stratosphere, the atmospheres secondlowest layer.
It also introduces various international agreements and. Ozone depletion begins, and the ozone hole appears. Students will use analysis and interpretation of data to develop a model to explain the cause and effect of ozone depletion. The mechanism underlying this enhanced ozone depletion. The montreal protocol is an international agreement to address the causes of ozone depletion. However, various factors have led to the depletion and damage of this protective layer.
Ozone layer depletion, its causes and its effects ozone. Uv radiations are disturbing developmental and physiological processes which is decreasing the productivity of crops. One of the main reasons for the widespread concern about depletion of the ozone layer. Stratospheric ozone protection awards since 1990, epa has recognized outstanding achievement in ozone layer protection. 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. Ozone depletionis primarily caused by human activities. The depletion of ozone in the stratosphere by the number of gaseous pollutants like nitric oxide no, nitrous oxide n2o, chlorine cl, chlorofluorocarbons cfcs etc. We use a chemistryclimate model and new estimates of smoke produced by fires in contemporary cities to calculate the impact on stratospheric ozone of a regional nuclear war between developing nuclear states involving 100 hiroshimasize bombs exploded in. What are the mechanisms of ozone depletion environmental. Cfcs, hcfcs, halons, methyl bromide, carbon tetrachloride methyl chloroform. The causes, mechanism and bioeffects of ozone layer depletion on humans were addressed.
Chemical reactions on the surfaces of ice crystals in the clouds release active forms of cfcs. What are the causes and effects of ozone depletion. This happens when the chlorine and bromine atoms in the atmosphere come in contact with ozone and destroy the ozone molecules. Frequently asked questions about the ozone layer ozone. However, because ozone absorbs solar radiation and is a greenhouse gas, ozone changes and climate change are linked in important ways. Ozone gas is perceptibly blue in colour and has a characteristic pungent smell. The increase in the levels of uv rays lead to high rate of skin cancer and eye related problems. In the late 1990s, average ozone depletion in the summer over canada was between 3% and 7%. European environment agency for the status of the currently ongoing ozone hole, you can visit the copernicus web site. A region of the considerable ozone depletion is named an ozone hole. Ozone depletion occurs when the natural balance between the production and destruction of stratospheric ozone is tipped in favour of destruction. The most harmful effects of ozone depletion greentumble air pollution february 24, 2016 one of the primary functions of the ozone layer is to filter out the majority. Consequently, ozone depletion and the related lack of heating cool the stratosphere indeed, the antarc. New scientific evidence proves ozone depletion theory false.
Ozone layer depletion is the thinning of the ozone layer present in the atmosphere. Jan 20, 2010 the montreal protocol is an international agreement to address the causes of ozone depletion. Clean development mechanism cdm, increased and subsequently peaked at 14 gg yr. What are the mechanisms of ozone depletion environmental sciences essay. The ozone layer typically occurs in the stratosphere and is naturally formed and decomposed from the reactions between oxygen and oxygen free radicals. Newly detected ozonedepleting substances in the atmosphere pdf. Depletion to ozone layer depletion does not affect a region or a country. Find answers to frequently asked questions about the ozone layer, ozone depletion, and the effects of ozone depletion on health and the environment. Ozone depletion and climate change are indirectly linked because both ozonedepleting substances and their substitutes are greenhouse gases.
Ozone depletion is allowing the uv radiation to earth surface. These ashes contain high concentration of bromine and chlorine. Ozone absorbs a band of ultraviolet radiation called uvb. Learn more about the process, causes, and effects of ozone layer depletion. The depletion of ozone layer leads to an increase in th e amount of harmful uvr at ground level. Ozone in the ozone layer is formed by the action of solar ultraviolet light on oxygen. It is a colourless gas that has a very strong smell. Case study on ozone layer free download as powerpoint presentation. 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.
The chlorofluorocarbon and the halons are potent ozone depletors. This lesson provides an insight into the phenomenon of ozone layer depletion, along with its mechanism and effects. It is revealed that introduction of chloroflourocarbons cfcs in the environment is the most rated cause of said depiction. Click download or read online button to get acid rain and ozone layer depletion book now. The the causes and effects of global ozone depletion have been illuminated in this paper. It is an essential factor for many global, biological and environmental phenomena.
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. Depletion of stratospheric ozone o3, as commonly known as the hole in the ozone layer, is an issue of international concern. The term ozone layer being very popular in the mass media is misleading. Nearly 90% of earths ozone is in the stratosphere and referred to as the ozone layer. It protects us from harmful uv radiations emitted from.
Ozone depletion simple english wikipedia, the free encyclopedia. The natural distribution of ozone around the earth is. Ozone depleting substances are those substances which deplete the ozone layer. Causes of ozone depletion depletion of the ozone layer is due to the emission of a set of chemicals that cause ozone to convert into oxygen. Causes and effects of ozone layer depletion that are.
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