Ozone is formed by photochemical reaction, followed by three body reaction. Sep 30, 2019 ozone depletion is largely a result of manmade substances. 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 severe depletion of the ozone layer in any particular area is called ozone hole. Ozone depletion facts and information national geographic. Ozone o3 is a stratospheric layer that plays important role in providing support to humans for their survival. 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 humans, a depleted ozone layer would likely mean high. It contains high concentrations of ozone o3 relative to other parts of the atmosphere. Presence of ozone in the lower atmosphere is considered as a pollutant and a greenhouse gas. It is found that the ozone layer gets affected by some natural causes that are sunspots and stratospheric winds. The ozone layer or ozone shield is a region of earths stratosphere that absorbs most of the suns ultraviolet radiation.
It protects life on earth from the suns ultraviolet uv rays. Ozone depleting substances are the substances such as chlorofluorocarbons, halons, carbon tetrachloride, hydrofluorocarbons, etc. Presence of ozone in the lower atmosphere is considered as a pollutant and a. Ozone forms a layer in the stratosphere protecting plants and animals from much of the suns harmful uvradiation. Pdf causes of ozone layer depletion and its effects on. Negative effects include increases in certain types of skin cancers, eye cataracts and immune deficiency disorders. The day the montreal protocol was agreed upon, 16 september, is now celebrated as the international day for the preservation of the ozone layer. Global warming and ozone layer depletion are two different problems see the sidebar misconceptions about global atmospheric change on page 95. The earth is protected from excessive ultraviolet rays. These chemicals are found in cleaning agents, aerosols, insulating foam, and refrigerants.
The chlorofluorocarbon and the halons are potent ozone depletors. Ozone depletion displaying top 8 worksheets found for this concept some of the worksheets for this concept are activity pack for key stages 2 3, tthe ozone hole and global he ozone hole and global global, national aeronautics and the ozone hole space administratio n, the good the bad and the ugly of ozone, causes of ozone layer depletion and its effects on human, ozone. Now, with continued compliance, we expect substantial recovery of the ozone layer by the late 21st century. Some halocarbons ozone depleting substances, or odss deplete the ozone layer, while others greenhouse gases, or ghgs are thought to contribute to global warming. Presentation on ozone depletion free download as powerpoint presentation. Apr 18, 2019 the ozone layer helps to protect life from harmful ultraviolet radiation. However, the ozone layer is destroyed by manmade chemicals known as ozonedepleting substances ods. Ozone depletion atmospheric ozone layer depletion is a serious problem currently facing the world. Ozone depletion and climate change environment canada. Ozone is a naturally occurring gas that is found in two layers of the atmosphere. 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.
Ozone and environment ozone o3 a gas composed of three atoms of oxygen bluish gas that is harmful to breathe nearly 90% of the earths ozone is in the stratosphere and is referred to as the ozone layer ozone absorbs a band of ultraviolet radiation called uvb ozone depleting substances ods. The main effect of ozone depletion is an increase in uvb rays reaching the earths surface. However, these cause a very nominal contribution to the ozone layer depletion which is near about 1 to 2 percent and therefore these. Ozone depletion caused by cfcs explains the onset and termination of recent global warming. The ozone layer refers to a region of earths stratosphere that absorbs most of the suns uv radiation. The first report of depletion in o 3 layer came out in the 1980s by an atmospheric scientist in antarctica. Since the 1970s, sunbathers have been avoiding the midday sun and using more sunscreens, hats, and protective clothing. When cfc is released into the atmosphere, they mix with atmospheric. There are also springtime polar tropospheric ozone depletion. Increased depletion has recently started occurring over the arctic as well. Depletion of the ozone layer occurs globally, however, the severe depletion of the ozone layer over the antarctic is often referred to as the ozone hole. The ozone layer contains less than 10 parts per million of ozone, while the average ozone concentration in earths. One chlorine can destroy 100,000 molecules of ozone.
Project report on ozone depletion environmental pollution. Ozone depletion, ozone hole, ultraviolet radiation. A depletion of the ozone layer will increase the uvradiation at ground level. Ozone depletion is largely a result of manmade substances. The latter phenomenon is referred to as the ozone hole.
A close look at the evolution at the life on earth reveals that initially the. In this photograph, the two lowest layers of the atmosphere, the troposphere and the stratosphere, are clearly visible. Ozone in the stratospherea layer of the atmosphere between 15 and 50 kilometers 10 and 31. Ozone depletion is primarily caused by human activities. Hence, cfcs are transporting agents that are responsible for damaging the ozone layer. An ongoing international collaboration the most recent wmounep scientific assessment of ozone depletion. Causes of ozone layer depletion and its effects on human.
Ozone layer depletion cause, effects, and solutions. Approximately 90% ozone is present in stratosphere at the height of 10 to 17 kilometer and is called ozone layer while remain ing 10% is present in troposphere 3. In the 1980s, scientists began finding clues that the ozone layer was being depleted. Ozone depletion and global warming overview page 1 of 5 halocarbons are chemical compounds containing carbon, one or more halogens, and sometimes hydrogen. Ozone layer is also naturally broken down but there is a balance between its formation and natural depletion.
With growing awareness of the gradual depletion of the ozone layer and of the deleterious effects of excessive sun exposure, sunbathing seems to be waning in popularity. Approximately 90 percent of the atmospheres ozone occurs from 1018 km 611 miles to. Ozone layer depletion is one of the major environmental issues which is getting thinner day by day as a result of increasing pollution. Although it represents only a tiny fraction of the atmosphere, ozone is crucial for life on earth. 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. In the layer surrounding the earths surface, the troposphere, ground level or bad ozone is an air pollutant that is a key ingredient to. Protecting the ozone layer and reducing global warming. The ozone loss is very small near the equator and increases with latitude toward the poles.
This stopped increasing ozone depletion by 1995, stopping increases in global temperature by 1998. Ozone gas is perceptibly blue in colour and has a characteristic pungent smell. Industries that manufacture things like insulating foams, solvents, soaps, cooling things like air conditioners. Ozone layer depletion is one of the major environmental issues which is getting thinner day by day as a. Ozone depletion biology science fair project ideas. It has been found that this protective ozone layer is getting depleted because of the presence of cfc chlorofluorocarbon compounds. Generally, we find thinning or depletion of the ozone layer to the extent of ozone hole creation over the southern pole i. Presentation on ozone depletion ozone depletion medicine. 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. Ozone layer depletion causes, effects and solutions 7. Environmental studies ozone depletion tutorialspoint. This, in turn, will lead to the breakdown of ozone. The average depletion exceeds the natural variability of the ozone layer. How severe is the depletion of the antarctic ozone layer.
The increase in the levels of uv rays lead to high rate of skin cancer and eye related problems. This website addresses stratospheric ozone issues, including the science of ozone depletion, epas regulatory approach to protecting the ozone layer, epa. Ozone layer depletion is simply the wearing out reduction of the amount of ozone in the stratosphere. The ozone layer protects earth from dangerous uv radiation fig. The ozone levels have declined as a consequence of cfcs and halons released into the atmosphere. The book concludes with a consideration of the possible e. But through domestic and international action, the ozone layer is healing and should fully recover by about 2065. However, the ozone layer is destroyed by manmade chemicals known as ozone depleting substances ods. Increasing production of cfcs was stopped by 1993 as a result of the united nations montreal protocol on substances that deplete the ozone layer. The ozone layer protects humans, animals, and plants from harmful ultraviolet rays. A dynamic equilibrium is maintained between the formation and decomposition of ozone.
Since ozone layer depletion allows greater amounts of uvb radiation to penetrate through our atmosphere. Depletion to ozone layer depletion does not affect a region or a country. This happens when the chlorine and bromine atoms in the atmosphere come in contact with ozone and destroy the ozone molecules. Publications about the ozone depletion theory of global. They are different in that climate change primarily involves temperature change, whereas ozone depletion involves the loss of a protective layer in the upper atmosphere. Money and time are being spent on ozone repair, but the problem still exists. The ozone layer is mainly found in the lower portion of the stratosphere. Furthermore, three chapters deal with the interaction between climate change and stratospheric ozone depletion as well as model predictions about the future development of the stratospheric ozone layer.
Twenty questions and answers about the ozone layer. The ozone layer is made up of ozone molecules, like ozzy ozone, and forms a thin shield high up in the sky. Causes, effects and solutions of ozone layer depletion. Life is protected from uv rays by stratospheric ozone layer which acts as a shield or sun screen 2. The health effect on humans from ozone depletion is widely varied. Ozone layer, region of the upper atmosphere, between roughly 15 and 35 km 9 and 22 miles above earths surface, containing relatively high concentrations of ozone molecules. The third body m absorbs the excess energy liberated by the above reaction and there by stabilise the o 3 ozone molecule. Ozone layer depletion definition, causes, solutions toppr. Ozone layer the ozone layer is basically naturally occurring gas in the region of stratosphere where ozone particles are accumulated 2. It is revealed that introduction of chloroflourocarbons cfcs in the environment is the most rated cause of said depiction. Timeline of stratospheric ozone depletion and observations. Warmer temperatures reduced the rate of ozone depletion. The ozone layer was discovered in 19 by the french physicists charles fabry and henri buisson.
Ozone depletion results in an increase of uvb radiation, but the shorter the wavelength, the stronger the increase within the uvb range. Ozone depletion consists of two related events observed since the late 1970s. As a consequence, total ozone depletion was unusually low that year in comparison with 2001 and 2003 and all other years since the early 1990s see figure q112. The uvb wavelengths cause skin cancer, sunburn, aging and. Why the ozone layer is vital to life on earth the ozone layer is a protective shield that blocks the suns harmful ultraviolet rays from reaching the earths surface.
Electromagnetic energy coming from the sun is absorbed by the earth, which. Since ozone is the earths protection against ultraviolet uv radiation, a reduction in the ozone layer causes more uvb wavelengths to reach the surface of the earth. Uv radiation also affects terrestrial and aquatic ecosystems, altering growth, food chains and biochemical cycles. The main effect of ozone depletion is an increase in uvb rays reaching the earths surface causes. Pdf there are many situations where human activities have significant effects on the environment. What are the causes and effects of ozone depletion. The emission of ozone depleting substances has been damaging the ozone layer. Humans have introduced gases and chemicals into the atmosphere that have rapidly depleted the ozone layer in the last century. Ozone in the stratospherea layer of the atmosphere between 15 and 50 kilometers 10 and 31 miles above usacts as a shield to protect earths surface from the suns harmful ultraviolet radiation. Ozone layer depletion leads to decrease in ozone in the stratosphere and increase in ozone present in the lower atmosphere. The thinning or reduction of ozone depletion is most prominent in the polar regions, especially over antarctica. Oct 27, 2017 what are the effects of ozone depletion. As you may know, we decline a substantial proportion of manuscripts without sending them to referees, so that they may be sent elsewhere without delay.
Epa relies on the atmospheric and health effects framework model to discover the health benefits of greater ozone layer protection via the montreal protocol. Ozone depletion refers to the wearing out or reduction of the amount of ozone in the stratosphere. The causes, mechanism and bioeffects of ozone layer depletion on humans were addressed. Although ozone is present in small concentrations throughout the atmosphere, most around 90% exists in the stratosphere, a layer 10 to 50 kilometres above the earths surface. Cfcs, hcfcs, halons, methyl bromide, carbon tetrachloride, and methyl chloroform. How large is the depletion of the global ozone layer. 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. Prolonged exposure to uvb radiation is linked to skin cancer, genetic damage and immune. The ozone layer protects living things from harmful ultraviolet rays from the sun. Ozone depletion is allowing the uv radiation to earth surface. The ozone layer has been depleted gradually since 1980 and now is about an average of 4% lower over the globe. Ozone layer depletion causes increased uv radiation levels at the earths surface, which is damaging to human health.
In fact whole world is vulnerable to its after affects. Difference between climate change and ozone depletion. It is an essential factor for many global, biological and environmental phenomena. Newly detected ozonedepleting substances in the atmosphere pdf. Ozone in the lower atmosphere contributes to global warming and climate change. The ozone layer is a region of the stratosphere containing ozone, or o3 gas. There are natural processes that create and destroy ozone in the stratosphere. Ozone depletion ozone layer depletion, is simply the wearing out reduction of the amount of ozone in the stratosphere. Ozone layer depletion is the thinning of the ozone layer present in the atmosphere. 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.
There are many situations where human activities have. 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. When highenergy ultraviolet rays uvc strike an oxygen. Climate change and ozone depletion are similar in that they are both changes to the environment caused by human civilization releasing a substance into the atmosphere. It was first identified in 1970s due to the advent of supersonic aircraft, which fly in the lower stratosphere and emit nitrogen oxides. As a result the total amount of ozone remains constant. Following is the list of some of the main ozone depleting substances and the sources from where they are released. At the same time, we have ensured that businesses and consumers have alternatives that are safer for the ozone layer than the chemicals they replace. Presentation on ozone depletion linkedin slideshare. The ozone layer helps to protect life from harmful ultraviolet radiation.
Global warming is caused by the greenhouse effect, which is essential to life as we know it on planet earth. Unlike pollution, which has many types and causes, ozone depletion has been pinned down to one major human activity. Find out what caused the ozone hole, and how the 1989 montreal protocol sought to put an end to ozone depletion. 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 thinning is most pronounced in the polar regions, especially over antarctica. Ozone is unstable and decomposes to molecular oxygen. The natural distribution of ozone around the earth is. These vital measures are helping to protect human health and the global environment. Uncovering the hidden hazard of hairspray a usual morning routine might include a spritz of hairspray, a spurt of shaving cream, or a spray of deodor. This depletion makes humans more vulnerable to the uvb rays which are known to cause skin cancer as well as other genetic deformities.
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