Introduction living beings and the environment are in constant interaction with one another. Causes and effects of ozone layer depletion that are. Newer calculation methods could reproduce the geometry as well as the vibrational frequency bands of o 3. In the earths atmosphere, the ozone comprises of the stratosphere which is 15 to 30 kilometers above the earths surface. The sun propagates ultraviolet radiations which as an adverse effect on living beings. The ozone layer depletion causes many types of damage such as skin cancer, cataract, adverse effect to crop and plant growth. There are also springtime polar tropospheric ozone depletion. The earths ozone layer ozone layerthe region of the stratosphere containing the bulk of atmospheric ozone. The ozone layer is a pretty small part of the atmosphere, consisting of approximately three molecules for every 10 million molecules of air. Ozone is unstable and decomposes to molecular oxygen. Ch 3 cl is derived mainly from natural sources and contributes to the destruction of the stratospheric ozone layer. First it absorbs some of the higher energy uv rays from the sun in the same way a cloud absorbs and reflect some of the visible light. The most commonly known example is the ozone layer, in which ozone is produced by ultra violet rays uv, which derive from the sun.
The uv light that the ozone layer protects us from is a necessary component in the creation of ozone molecules. The production and emission of chlorofluorocarbons cfcs, is the leading cause of ozone layer depletion. The ozone layer or ozone shield is a region of earths stratosphere that absorbs most of the. Ground ozone concentration is lower in polar and equatorial regions. The ozone layer or ozone shield is a region of earths stratosphere that absorbs most of the suns ultraviolet radiation. These chemicals are found in cleaning agents, aerosols, insulating foam, and refrigerants. Function of the ozone layer e ects of ozone depletion structure of the ozone layer formation of the ozone layer depletion of the ozone layer ozone layer recovery 8 of 31 lecture question where is the ozone layer and how concentrated is it. The maps were produced with data collected by statellite istruments, including the ozone monitoring instrument on the aura satellite. It was first discovered in 1839 by christian friedrick schonbein who noticed it because of its distinctive acrid smell.
The dobson spectrophotometer plays a key role in groundbased ozone monitoring efforts. Arabidopsis harmless to ozone layer protein methylates a. However, because it occurs in such a low concentration, its vulnerable to ozonedepleting chemicals, such as cfcs. There are natural processes that create and destroy ozone in the stratosphere. Quantifying contributions of chlorofluorocarbon banks to. Ozone layer is also naturally broken down but there is a balance between its formation and natural depletion.
Ozone is a naturally occurring gas that is found in two layers of the atmosphere. The ozone layer is one layer of the stratosphere, the second layer of the earths atmosphere. When cfc is released into the atmosphere, they mix with atmospheric. During the long winter months of darkness over the antarctic, atmospheric temperatures drop. Ozone depletion consists of two related events observed since the late 1970s. The role of hfcs in mitigating 21st century climate change. The ozone layer high in the earths atmosphere blocks much of this radiation from reaching the surface. What is the function of the atmospheres ozone layer. Then, when those oxygen atoms come into contact with oxygen gas, they join to become ozone. Ozone layer depletion is one of the major problems for the atmosphere and also for all the living beings including the flora and fauna of this earth.
Ozone, chemical reactivity and biological functions. The main effect of ozone depletion is an increase in uvb rays reaching the earths surface causes. Ozone layer stratospheric ozone is a high concentration of ozone molecules about 30 to 50 km altitude stratosphere. Global biogeochemical cycles consist of the transport and transformation of substances in the environment through life, air, sea, land, and ice alexander et al. The impact of the interaction of climate changes and ozone depletion on the expected levels of ambient uv. An examination of atmospheric changes in australia from 1979 to 1992 has shown that the deseasonalised time series of uvr exposures were a linear function of. Causes of ozone layer depletion and its effects on human. The physical, chemical and biological factors that constitute any given environment have a. Learn vocabulary, terms, and more with flashcards, games, and other study tools. Ozone layer depletion cause, effects, and solutions. In essence, it functions like a sponge and soaks up harmful radiation from the sun. Dense layers of molecular gases also absorb cosmic rays, gamma rays and xrays, preventing these energetic particles from striking living things and causing mutations and other genetic damage. National aeronautics and the ozone hole space administratio n. The stratosphere is the mass of protective gases clinging to our planet.
Ozone layer introduction the ozone layer refers to the ozone within stratosphere, where over 90% of the earths ozone resides. For exam ple, ozone initiates the chemical removal of many pollutants, such as. Causes, effects and solutions of ozone layer depletion. The ozone layer contains less than 10 parts per million of ozone, while the average ozone concentration in earths. The ozone layer is composed of ozone, a molecule made up of three oxygen atoms bonded together. When uv rays strike an oxygen molecule, it breaks the oxygen down into two atoms of oxygen. Through these cycles, the planets climate, ecosystems, and creatures 45 1. 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.
Ozone depletion and climate change have usually been thought of as environmental issues with little in common other than their global scope and the major role. Ozone depletion is primarily caused by human activities. Environmental studies ozone depletion tutorialspoint. He discovered this at the university of basel in switzerland. The main function of the ozone layer is to absorb the suns ultraviolet radiation, hence protecting the earth from its harmful effects. However, despite this size, the role the ozone layer plays is an important one. The ozone layer is composed of ozone, a molecule made up of. Ozone in the stratosphere absorbs some of the suns biologically harmful ultraviolet radiation. Ozone may make it more difficult for you to breathe as deeply and vigorously as you normally would.
It is an allotrope of oxygen that is much less stable than the diatomic allotrope o 2, breaking down in the lower atmosphere to o 2. A dynamic equilibrium is maintained between the formation and decomposition of ozone. When highenergy ultraviolet rays uvc strike an oxygen. The ozone hole is not really a hole but a thinning of the ozone layer over the south polar region. 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. In the layer surrounding the earths surface, the troposphere, ground level or bad ozone is an air pollutant.
Ozone depletion refers to the wearing out or reduction of the amount of ozone in the stratosphere. Ozone is harmful at ground level but high up the atmosphere ozone layer plays a vital role in the protection of all living beings. The ozone layer is a layer in earths atmosphere which contains relatively high concentrations of ozone o3. Understanding the composition and function of the ozone layer. The importance of the ozone layer and its structure. This layer absorbs the radiations and prohibits them from entering the outer surface of the earth. The ozone layer lies approximately 1540 kilometers 1025 miles above the earths surface, in the stratosphere. It has been found that this protective ozone layer is getting depleted because of the presence of cfc chlorofluorocarbon compounds. The stratosphere increases in warmth with elevation because ozone gases in the upper layers absorb. Dubay outlines the nature and role of the ozone layer. We assessed the increase of skin cancer incidence risk. Approximately 90 percent of the atmospheres ozone occurs from 1018 km 611 miles to about 50 km about 30 miles above earths surface. Every year, since at least 1978, there is a sudden, rapid decrease in the stratospheric ozone levels at the end of the antarctic winter. The ozone layer is located at the height from 20 to 40 km above the sea level, and it is located in the lower part of the stratosphere layer, as it is the first layer of the atmospheric envelope which contains a suitable amount of oxygen gas, and it also faces the ultraviolet radiations that emitted from the sun the structure of the ozone layer.
Ozone o3 is a molecule made up of three atoms of oxygen o, and is mostly found in the strato sphere, where it protects us from the suns harmful ultraviolet. The highest levels of ozone in the atmosphere are in the stratosphere, in a region also known as the ozone layer between about 10 km and 50 km above the surface or between about 6 and 31 miles. The purpose of our study was to develop damage functions due to ozone layer depletion, that related the emission of ozone depleting substances ods to the damage of category endpoints. Ozone depleting substances are those substances which deplete the ozone layer. Ozone can reduce lung function when scientists refer to lung function, they mean the volume of air that you draw in when you take a full breath and the speed at which you are able to blow it out. The importance of the ozone layer and its structure you should know that the ozone layer is located at the height from 20 to 40 km above the sea level, and it is located in the lower part of the stratosphere layer, as it is the first layer of the atmospheric envelope which contains a suitable amount of oxygen gas, and it also faces the. The ozone hole is shown in purple above the antarctic on sept.
The concentration of ozone in the ozone layer is usually under 10 parts ozone per million 5. Ozone is an irritating, corrosive, colorless gas with a smell something like burning electrical wiring. 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 plays important roles in the atmosphere beyond absorbing uv radiation. Timeline of stratospheric ozone depletion and observations. Ozone is formed from dioxygen by the action of ultraviolet uv light and electrical discharges within the. Development of damage function for stratospheric ozone. Progress report 2003 united nations environment programme, environmental e.
Because of this beneficial role, stratospheric ozone is considered. As a result the total amount of ozone remains constant. Pdf causes of ozone layer depletion and its effects on. The ozone layer is a deep blanket in the stratosphere made up of comparatively high concentration of the ozone. The structure and function of the ozone layer youtube.
International electronic journal of environmental education, 71, 116. The function of the ozone layer is to shield the earth from the harmful ultraviolet rays of the sun and to keep the earth warm. The stratosphere gets its name because it is stratified, or layered. The parts of the uv light absorbed or reflected is very harsh on the. Ozone layer depletion definition, causes, solutions toppr. The latter phenomenon is referred to as the ozone hole. A combination of low temperatures, elevated chlorine, and bromine concentrations in the upper stratosphere are responsible for the destruction of ozone.
Ozone layer depletion means the thinning of the ozone layer present in the upper atmosphere. Basic ozone layer science ozone layer protection us epa. It is a pale blue gas with a distinctively pungent smell. As the total abundance of ozonedepleting gases such as chlorofluorocarbons in the atmosphere has begun. The ozone layer in the stratosphere is thin but powerful. Approximately 90 percent of the atmospheres ozone occurs from 1018 km 611 miles to.
In our present study, we shall discuss how ozone layer depletion is affecting human health and we shall also discuss some recommendations to minimize ozone depletion and its adverse effects on human health. Ozone layer the ozone layer is basically naturally occurring gas in the region of stratosphere where ozone particles are accumulated 2. The function of the atmospheres ozone layer is that it keeps the earth warm by preventing the heat energy reflected by the earths surface from being reradiated into space. It has the potential to absorb around 9799% of the harmful ultraviolet radiations coming. Methyl chloride ch 3 cl is the most abundant halohydrocarbon emitted into the atmosphere and constitutes about 17% of the chlorine currently in the stratosphere. The ozone ozone derives from the greek word ozein which means to smell.
What are the causes and effects of ozone depletion. Stratospheric ozone depletion, ultraviolet radiation and health. Photolysis of atmospheric ozone in the ultraviolet region pdf. The vienna convention for the protection of the ozone layer. Ozone is a triatomic form of oxygen o 3, found in the earths atmosphere. Overall, ozone may resemble a folded heterocumulene. 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. Global actions have demonstrably avoided a world in which large ozone losses would have become widespread 1 and there are signs that the ozone layer is. Herb burack, in comprehensive series in photosciences, 2001. Ozone depletion and climate change environment canada.
What is the ozone layer and how does it affect you. Ozone is naturally produced through certain types of chemical reactions. The ozone layer is a region in the earths stratosphere that contains high concentrations of ozone and protects the earth from the harmful ultraviolet radiations of the sun. Pdf there are many situations where human activities have significant effects on the environment. This layer absorbs 9799% of the suns high frequency ultraviolet light, which is potentially damaging to life on earth.
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