While ozone depletion has initiated concern about the effects of increased uvb on the biosphere, uvb filtered. Ozone is an irritating, corrosive, colorless gas with a smell something like burning electrical wiring. If the ozone layer over the us were compressed to 0 degrees celsius and 1 atmosphere pressure, it would be about 3 mm thick. Photolysis of atmospheric ozone in the ultraviolet region pdf. Uv radiations are disturbing developmental and physiological processes which is decreasing the productivity of crops. Introduction to the special issue on ozone layer protection. Handbook for the montreal protocol on substances that. It can be found on the earths surface as well used for such things as bleaching, sterilizing water, and removing unpleasant smells from products.
Ozone is naturally produced through certain types of chemical reactions. Once one has compared all the options and alternatives, ozone therapy arises, head and shoulders above all the rest, as the most compelling. Approximately 90 percent of the atmospheres ozone occurs from 1018 km 611 miles to. The ozone hole is not really a hole but a thinning of the ozone layer over the south polar region. Ozone layer depletion essay sample new york essays. It can be found on the earths surface as well used for such things as bleaching, sterilizing water, and removing unpleasant smells. In addition, all figures are available for download, in three formats. The thinning is most pronounced in the polar regions, especially over antarctica.
The ozone layer has historically protected the earth from the harmful uv rays, although in recent decades this protection has diminished due to stratospheric ozone depletion. This timeline highlights milestones related to the history of. Mar 27, 2014 if the ozone layer over the us were compressed to 0 degrees celsius and 1 atmosphere pressure, it would be about 3 mm thick. The protocol to the convention, the montreal protocol on substances that deplete the ozone layer the. Reading check explain the benefits of ozone in the atmosphere. However, ozone gas doesnt just coat our earths stratosphere.
Ozone layer introduction the ozone layer refers to the ozone within stratosphere, where over 90% of the earths ozone resides. Protecting the ozone layer department of the environment. Pdf on jan 1, 2001, md safiuddin and others published global ozone depletion. Click download or read online button to get acid rain and ozone layer depletion book now. Project report on ozone depletion environmental pollution. Although ozone represents only a small fraction of the gas present in the atmosphere, it plays a vital role by shielding humans and other life from. However, the ozone layer is destroyed by manmade chemicals known as ozonedepleting substances ods. The ozone layer is a layer of ozone high up in the earths atmosphere stratosphere. By the year 2020 in the simulation, 17% of the earths protective ozone layer vanished. If the ozone layer is depleted by human action, the effects on the planet could be catastrophic. Ozone layer research and technical resources us epa.
Ozone depletion is largely a result of manmade substances. Ozone is formed by photochemical reaction, followed by three body reaction. Depletion of stratospheric ozone o3, as commonly known as the hole in the ozone layer, is an issue of international concern. This layer absorbs 9399% of the suns high frequency ultraviolet light, which is potentially damaging to life on earth 1. Pdf causes of ozone layer depletion and its effects on.
It is an essential factor for many global, biological and environmental phenomena. Causes of ozone layer depletion and its effects on human. The ozone layer contains less than 10 parts per million of ozone, while the average ozone concentration in earths. 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 resulting increase in ultraviolet radiation at earths. Ozone depletion potential an overview sciencedirect topics. Exposure to sunlight is generally an unavoidable consequence of being alive and life on earth relies on the ozone layer to attenuate biologically harmful ultraviolet b uvb. Ozone depletion describes two distinct but related phenomena observed since the late 1970s.
Introduction to how the ozone layer works howstuffworks. Ozone gas has become so synonymous with the ozone layer that people now refer to the layer as the ozone. During the long winter months of darkness over the antarctic, atmospheric temperatures drop. The ozone layer that protects earth is located in the stratosphere. Introduction ozone is a gas that occurs naturally in our atmosphere. Downloads scientific assessment of ozone depletion 2018. Presentation on ozone depletion linkedin slideshare. 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. The exact amount of ozone that can be found varies, the seasons influence it. Most of it is concentrated in the ozone layer, a region located in the stratosphere several miles above the surface of the earth. But our atmosphere is still vulnerable, and it is not clear whether the ozone layer of the future will look like the ozone layer we had in the past.
National aeronautics and the ozone hole space administratio n. The ozone molecule is very unstable and has a short halflive, causing it to fall back into its original form after a while, according to the following reaction mechanism. The sun propagates ultraviolet radiations which as an adverse effect on living beings. Issues and concerns about the ozone layer depletion introduction the ozone layer protects the earth from the ultraviolet rays sent down by the sun. It will take generations before we know how the experiment turned out.
Introduction to the special issue on ozone layer protection and climate change. The third body m absorbs the excess energy liberated by the above reaction and there by stabilise the o 3 ozone molecule. All of the assessment documents core assessment report, executive summary, and twenty questions and answers about the ozone layer. 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 ozone treaties hold the rare distinction of having been ratified by every country in the world. The causes and effects of the depletion of the ozone layer and climate change are seen by. Ozone o 3 is a gas with molecules made of three atoms of oxygen. The ozone layer lies approximately 1540 kilometers 1025 miles above the earths surface, in the stratosphere. The stratospheric ozone layer effectively serves as a protective shield that reduces the harmful ultraviolet radiation uv. The 1985 vienna convention for the protection of the ozone layer, along with its montreal protocol on substances that deplete the ozone layer, is widely regarded as one of the most successful global environmental agreements in history. Ozone o 3 is a stratospheric layer that plays important role in providing support to humans for their survival. This is different from the oxygen we breath o 2, which has two atoms of oxygen and makes up 21% of the earths atmosphere.
Pdf causes of ozone layer depletion and its effects on human. When highenergy ultraviolet rays uvc strike an oxygen. Ozone concentration differs by about 10 ppm in stratosphere compared to 0. Ozone absorbs a band of ultraviolet radiation called uvb. In the early 1980s, scientists measuring the amount of ozone over antarctica found the levels much lower than normal in october. Principally, an ozone molecule is nothing but an oxygen molecule that has received an extra oxygen atom by electric high voltage.
It covers the entire planet and protects life on earth by absorbing harmful ultravioletb uvb radiation from the sun. This site is like a library, use search box in the widget to get ebook that you want. Future previsions indicated that 50% increases in n 2 o result in a maximal 6% reduction in ozone layer in the midstratosphere and an average 2% decrease in the total ozone column. Handbook for the vienna convention for the protection of. 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 ozone layer shields the earth from harmful effects of solar ultra violet radiation, but can be decomposed by complex chemical reactions, notably involving chlorofluorocarbons cpas. 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. Introduction the ozone layer is a layer in earths atmosphere which contains relatively high concentrations of ozone o3.
The severe depletion of the antarctic ozone layer known as the ozone hole occurs because of the special meteorological and chemical conditions that exist there when the very low winter temperatures in the antarctic stratosphere cause polar stratospheric clouds pscs to form which are isolated from stratospheric air in the polar vortex. Acid rain and ozone layer depletion download ebook pdf. The ozone layer lies approximately 1540 kilometers 1025 miles above the earths surface, in the. There are natural processes that create and destroy ozone in the stratosphere. Twenty questions and answers about the ozone layer noaaesrl. Every year, since at least 1978, there is a sudden, rapid decrease in the stratospheric ozone levels at the end of the antarctic winter. This timeline highlights milestones related to the history of ozone depletion. The protective ozone layer is located in the stratosphere. The upper layer of the atmosphere surrounded by ozone 15 to 30 kms is known as ozonosphere.
International concern over the appearance of a hole in the ozone layer over the antarctic in the 1980s led to a movement for the cfc producing devices. It is revealed that introduction of chloroflourocarbons cfcs in the environment is the most rated cause of said depiction. 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 ozone layer gets its name from ozone gas, an allotrope, or form, of the element oxygen.
This layer absorbs the radiations and prohibits them from entering the outer surface of the earth. The ozone layer or ozone shield is a region of earth s stratosphere that absorbs most of the sun s ultraviolet radiation. Ozone is found throughout the earths atmosphere in minute quantities about 0. 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. Ozone secretariat the secretariat for the vienna convention for the protection of the ozone layer and for the montreal protocol on substances that deplete the ozone layer united nations environment programme nairobi, kenya ozone. By contrast, annual anthropogenic n 2 o ozone depletion potentialweighted emissions were the fourth most important in the 1980s. The importance of the ozone layer and its structure. Under average conditions, at ground level, each cm of ah contains around 10 19 molecules of all the gases present of which ozone concentration is about 0. It acts as a protective shield for the man, animals and. Approximately 90 percent of the atmospheres ozone occurs from 1018 km 611 miles to about 50 km about 30 miles above earths surface. The ozone layer or ozone shield is a region of earths stratosphere that absorbs most of the. The ozone layer or ozone shield is a region of earths stratosphere that absorbs most of the suns ultraviolet radiation. The convention was negotiated between 1981 and 1985 and has been ratified by 193 parties. They found that the ozone layer over antarctica lost ozone in late winter and early spring august to october in the southern hemisphere until it had 20% less ozone than normal.
Handbook for the vienna convention for the protection of the. Index terms bio effects, chlorofluorocarbon, ozone layer depletion, protection. In the region between about 10 kilometres and about 50 kilometres above ground, the atmosphere contains more ozone o 3. Depletion of ozone layer is also causing the problem of food shortage to humans. Ozone in the stratospherea layer of the atmosphere between 15 and 50. Handbook for the montreal protocol on substances that deplete. 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. A close look at the evolution at the life on earth reveals that initially the. In recent years, the ozone layer has been the subject of much discussion. Pdf depletion of the ozone layer and its consequences. Meteortrails space shuttle satellite troposphere 10 km 50 km 85 km 500 km ozone layer jet. Jun 26, 2012 ozone day poster, ozone layer drawing, ozone layer drawing pictures, ozone day drawing, ozone draw duration. Introduction 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.
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