Effects of uv rays on aquatic ecosystems ozone depletion causes increases in uv rayss effects on aquatic ecosystems by. 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. Other electrons from the n region cannot migrate because they are repelled by the negative ions in the p region and attracted by the positive ions. 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. The causes, mechanism and bioeffects of ozone layer depletion on humans were addressed. Ozone layer depletion cause, effects, and solutions. It is a very aggressive cancer and quickly grows inwards and causes secondary tumours to. 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. The ozone layer acts as a natural filter, absorbing most of the suns burning ultraviolet uv rays. Learn more about the process, causes, and effects of. The depletion of the ozone layer is a major concern today. It is an essential factor for many global, biological and environmental phenomena. Stratospheric ozone depletion leads to an increase in uvb that reach the earths surface, where it can disrupt biological processes and damage a number of materials the fact that uvb can cause biological effects is well demonstrated by the familiar sunburn that follows.
Efstathios demetriades3, kavala institute of technology abstract this study investigates the merger effects of two banks. Stratospheric ozone depletion is a concern because the ozone layer in the stratosphere keeps 9599% of the suns ultraviolet radiation from striking the earth. This website addresses stratospheric ozone issues, including the science of ozone depletion, epas regulatory approach to protecting the ozone layer, epaapproved alternatives to ozone depleting substances, and sun safety. 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. To conclude, it is crucial to clearly differentiate between what this book claims and what it does not. First, i do not claim that eventually solving climate change and other global environmental problems can be accomplished with less than universal participation. Ozone layer has been found to be affected by certain natural phenomenon such as sun spots and stratospheric winds. Ozone is an irritating, corrosive, colorless gas with a smell something like burning electrical wiring. The causes, mechanism and bio effects of ozone layer depletion on humans were addressed. The good news about the ozone hole is even better than you. The objective of firms varies according to the size of the businesses. The montreal protocol to the vienna convention, adopted in 1989, pinpointed a series of substances cfcs and halons believed to be the culprits of ozone layer depletion and mandated their gradual phasingout. The origins of uncertainty about the factors that affect the ozone layer are, as seen, very diverse. Let us see some of the important causes and effects of ozone layer depletion.
Case study depletion of ozone in the atmosphere the work of g. Addressing ozone layer depletion ozone layer protection. The ozone layer protects us from the harmful rays of the sun. Physics of semiconductor devices pn junction depletion. The the causes and effects of global ozone depletion have been illuminated in this paper. What are the depletion width in the nregion, the depletion width in the pregion, and the builtin potential at 300k.
Ozone is a molecule consisting of three oxygen atoms o3 and has the property of being highly toxic because of its radioactivity. Causes of ozone layer depletion and its effects on human. It is revealed that introduction of chloroflourocarbons cfcs in the environment is the most rated cause of said depiction. 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. As the eruption of mount pinatubo proved in 1991, natural eruptions can have a dramatic negative effect on the manmade ozone layer depletion chemicals that are in the atmosphere. Let us have a detailed look at the various causes and effects of ozone layer depletion. The ozone layer helps to protect life from harmful ultraviolet radiation. It is revealed that introduction of chloroflourocarbons cfcs in the environment is the most rated cause. Approximately 90 percent of the atmospheres ozone occurs from 1018 km 611 miles to about 50 km about 30 miles above earths surface.
Pdf causes of ozone layer depletion and its effects on. 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 ozonedepleting substances ods. Dramatically every spring you may have heard this called the ozone hole. The ozone depletion potential odp of a chemical compound is the relative amount of degradation to the ozone layer it can cause, with trichlorofluoromethane r11 or cfc11 being fixed at an odp of 1. B dobson and other scientists in measuring concentrations of chloride and ozone in the atmosphere g.
Causes and effects of ozone layer depletion that are truly dangerous duration. The depletion has lessened since then and now is about 3% averaged over the globe. Physics of semiconductor devices pn junction depletion width problem a silicon pn diode has a doping of n d 81015 1 cm3 and n a 210 16 1 cm3. The good news about the ozone hole is even better than you think. Cfc 11, or r11 has the maximum potential amongst chlorocarbons because of the presence of three. The electrons which had migrated across from the n to the p region in the forming of the depletion layer have now reached equilibrium. Find out what caused the ozone hole, and how the 1989 montreal protocol sought to put an end to ozone depletion. The ultraviolet uv rays emitted from sun are captured by ozone and thereby provide a stable ontological structure in the biosphere. Its causes, effects, and possible solutions essay sample. But it causes only 12% depletion and that is also temporarily.
A summary of the ozone depletion issue, below, with highlighted terms that you can click on for further information. Analyse the possible effects when a merger of two large companies occur and discuss why there is sometimes opposition to such mergers. It is found largely in the stratosphere that extends from about 6 km at the poles and 17 km at the equator to about 50 km above the earths surface. Ozone depletion facts and information national geographic. The same can, of course, be said for the other types of mergers. So, why is the ozone layer important to life on earth. The ozone layer is a protective shield that blocks the suns harmful ultraviolet rays. The main things that lead to destruction of the ozone gas in the ozone layer. Therefore, the ozone layer protects life on earth from the harmful effects of solar radiation on a daily basis. Learn more about the process, causes, and effects of ozone layer depletion. Developing countries mostly comprise of large firms while developing countries contain large and medium size firms. We use your linkedin profile and activity data to personalize ads and to show you more relevant ads. Ozone layer depletion and its ill effects in australia. Ozone o3 is a stratospheric layer that plays important role in providing support to humans for their survival.
The average depletion exceeds the natural yeartoyear variations of global total ozone. The main causes identified for depletion of resources are. Ozone layer introduction the ozone layer refers to the ozone within stratosphere, where over 90% of the earths ozone resides. The envelope of air or different types of gases surrounding the earth is known as atmosphere.
The stratospheric ozone layer completely stops the penetration of uvc rays and eliminates most of the uvb rays. Coulomb force from ions prevents further migration across the pn junction. What is an ozone hole and causes and effects of ozone. Experts blame ozonelayer depletion on manmade chemicals containing chlorine and bromine that are emitted from a. The thinning is most pronounced in the polar regions, especially over antarctica. Causes and effects of ozone layer depletion that are. 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. Obviously, both ozone depletion and climate change are problems with global extent that emerge from. 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. The ozone layer is responsible for absorbing harmful ultraviolet rays, and preventing them from entering the earths atmosphere. There is shortage of drinking water and water for irrigation. In semiconductor physics, the depletion region, also called depletion layer, depletion zone, junction region, space charge region or space charge layer, is an insulating region within a conductive, doped semiconductor material where the mobile charge carriers have been diffused away, or have been forced away by an electric field. There are many situations where human activities have.
Cfcs, hcfcs, halons, methyl bromide, carbon tetrachloride, and methyl. Since all horizontal mergers eliminate competition between the merging companies, any horizontal merger that meets our test for an increase in efficiency must do so because its net effect is to increase efficiency. Ozone depletion is allowing the uv radiation to earth surface. Timeline of stratospheric ozone depletion and observations. Low temperatures, increase in the level of chlorine and bromine gases in the upper stratosphere are some of the reasons that leads to ozone layer depletion. The various possible consequences of mergers are depicted in table 1. The effect of mergers and acquisitions on the performance. But through domestic and international action, the ozone layer is healing and should fully recover by about 2065. However, various factors have led to the depletion and damage of this protective layer. Chlorodifluoromethane r22, for example, has an odp of 0. Find out what caused the ozone hole, and how the 1989 montreal.
We often think of ozone layer depletion as a modern problem, but it is something that started well before the 1970s. Stratospheric ozone depletion s depletion of the global ozone layer increased gradually in the 1980s and reached a maximum of about 5% in the early 1990s. Various anthropogenic activities such as emissions of. Ozone layer depletion causes, effects and solutions 7. Case study on ozone layer free download as powerpoint presentation.
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