Due to ozone depletion harmful uv rays such as uv b radiation reaches to earth which leads to harmful effects on animals, plants, aquatic life as well as on humans also what are the consequences. A modeling study of the mechanism of the halogenozone. Pdf atmospheric ozone layer depletion and its impact. Cfcs, hcfcs, halons, methyl bromide, carbon tetrachloride, and methyl chloroform. Hence, cfcs are transporting agents that are responsible for damaging the ozone layer. If interested, you can purchase this powerpoint from my online store. Chlorine atoms catalyse the decomposition of ozone and contribute to the hole in the ozone layer. Feb 12, 2018 far above earths surface, the ozone layer helps to protect life from harmful ultraviolet radiation. Inexpensive light extremely stable, inert traditional refrigerants ammonia, sulfur dioxide, methyl chloride highly volatile caustic and toxic remove heat through vaporization of liquefied gas only adequate as refrigerants expensive heavy transport, storage. Evs global warming, ozone depletion ppt free download as powerpoint presentation. The first report of depletion in o 3 layer came out in the 1980s by an atmospheric scientist in antarctica. Ozone layer depletion is one of the major environmental issues which is getting thinner day by day as a result of increasing pollution. Besides carbon dioxide, other greenhouse gases are methane, water vapour, nitrous oxide, cfcs and ozone. Chlorine atoms react with ozone, starting a chemical cycle that destroys the good ozone in that area.
It is an allotrope of oxygen that is much less stable than the diatomic allotrope o 2, breaking down with a half life of about half an hour in the lower atmosphere to o 2. Ozone layer depletion causes affecting factors ozone hole etc. This was also the start of intensive research into the chemistry of the atmosphere. The ozone layer refers to a region of earths stratosphere that absorbs most of. These free downloadable chemistry ppt backgrounds are fully customizable with easytoedit theme color as well as text. View and download powerpoint presentations on ozone depletion ppt. It contains high concentrations of ozone o3 relative to other parts of the atmosphere. Appreciate that results of research by different groups in the scientific community provided evidence for legislation to ban the use of cfcs as solvents and refrigerants. Find powerpoint presentations and slides using the power of, find free presentations research about ozone depletion ppt. 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. Project report on ozone depletion environmental pollution.
This timeline highlights the average area of the ozone hole between september 7th and october th as observed by nasa spacedbased instruments see colored bars and scale. Ozone depleting substances are the substances such as chlorofluorocarbons, halons, carbon tetrachloride, hydrofluorocarbons, etc. Assessments of ozone depletion as an author, coauthor. Ppt ozone depletion powerpoint presentation free to. Learn what cfcs are, how they have contributed to the ozone hole, and how the 1989 montreal. 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. Following is the list of some of the main ozone depleting substances and the sources from where they are released. Its properties were explored in detail by the british. Eventually the spectrum of the missing radiation was matched to only one known chemical, ozone. Aqa organic chemistry halogenoalkanes ozone depletion.
The uploader spent hisher valuable time to create this depletion of ozone layer powerpoint presentation slides, to share hisher useful content with the world. Ozone layer depletion free download as powerpoint presentation. The thinning is most pronounced in the polar regions, especially over antarctica. Why the hole in the atmospheric ozone layer above us. 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. Ppt the stratospheric chemistry and the ozone layer powerpoint presentation free to download id. Ppt ozone layer depletion powerpoint presentation free. Prezi s director of product marketing on working from home and finding balance.
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. Atmospheric chemistry division at the national center for atmospheric. Ozone depletion describes two distinct but related phenomena observed since the late 1970s. Our ozone layer depletion ppt template is excellent for giving an indepth presentation about such a topic. Ods are mainly responsible for manmade chemical ozone depletion. This, in turn, will lead to the breakdown of ozone.
Presentation on ozone depletion linkedin slideshare. The ozone layer was discovered in 19 by the french physicists charles fabry and henri buisson. The global exchange between ozone and oxygen is on the order of 300 million tons per day. A twodimensional chemistry transport model of the global troposphere is used to study the chemical response to i increased uv radiation from stratospheric ozone depletion and ii increased. A free powerpoint ppt presentation displayed as a flash slide show on id. Cfcs nonflammable nontoxic trap heat good insulators. The action of water vapor on the stratospheric ozone chemistry. Ozone layer depletion penn state college of earth and. Ozone layer depletion powerpoint template sketchbubble. Ozone is formed throughout the atmosphere in multistep chemical processes that require sunlight. This video is highly rated by class 11 students and has been viewed 406 times. The ozone layer is a deep blanket in the stratosphere made up of comparatively high concentration of the ozone. Ozone hole environmental chemistry, class 11 class 11. Ozonedepleting substances odss and related chemicals.
Jun 09, 2016 the ozone in the stratosphere is continually being made and broken by ultraviolet light in the ozone oxygen cycle. The first manmade threat to the ozone layer was noted by harold johnston 1971. Plot of the percentage of depletion of ozone from 0 to 1400 h versus br 2 0 and ch 2 o 0 for computer simulations of the halogenozone chemistry at the location of barrow, alaska on 17 march. It shields the entire earth frommuch of the harmful uv radiationthat comes from the sun 3. The study in the low latitude region with the las data on 4 april 1984 indicates the clear anti. Ozone layer depletion ozone depletion chlorofluorocarbon. Chlorofluorocarbons cfcs and other halogenated ozone depleting substances ods are mainly responsible for manmade chemical ozone depletion. The ozone layer is mainly found in the lower portion of the stratosphere. This power point presentation is mainly focused on todays most challenging issue as depletion of ozone layer with major factors affecting it. Uv gets absorbed in the stratosphere by molecular oxygen, which splits into 2.
This extreme stability allows cfcs to slowly make their way into the stratosphere most molecules decompose before they can cross into the stratosphere from the troposphere. Qa conference,the chemistry of ozone in wastewater,the chemistry of ozone in wastewater created date. Presentation on the chemistry of ozone in wastewater keywords. 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. Carbon dioxide is the major contributor to global warming. This powepoint presentation deals on ozone layer, its importance, its depletion, consequences on human. A 2 % increase in uv radiation results in a 5 % to 7% increase in skin cancer, including a 1% increase in deadly malignant melanoma. Ozone depletion eric lin, cody lu natalie qin, silvia shi the ozone layer is essential to organisms because it protects them from harmful effects of the.
Halogen catalysis of ozone degredation halogens are a chemical family containing fluorine, chlorine, bromine and iodine. The causes, mechanism and bioeffects of ozone layer depletion on humans were addressed. Ozone layer depletion cause, effects, and solutions. Ozone hole environmental chemistry, class 11 class 11 video edurev is made by best teachers of class 11. Since montreal protocol 1987 small groups of the chemical industry, knowing that refrigerants. Ozone in the stratosphere is necessary to life as we know it because it absorbs energetic uv radiation. 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, humans and environment with. Evs global warming, ozone depletion ppt ozone depletion.
Ozone in the troposphere is toxic due to its reactive oxidizing capabilities. Unlike oxygen o2, ozone has a strong scent and is blue in color. Ozone gas is perceptibly blue in colour and has a characteristic pungent smell. Ozone absorbs a band of ultraviolet radiation called uvb. Chemistry of ozone depletion cfc molecules are made up of chlorine, fluorine and carbon atoms and are extremely stable. The ozone layer refers to a region of earths stratosphere that absorbs most of the suns uv radiation. Download free chemistry powerpoint templates to gain excel grade in your project work. Total bromine from halons has decreased from a peak of 8. Nearly 90% of earths ozone is in the stratosphere and referred to as the ozone layer. The action of water vapor on the stratospheric ozone chemistry is studied in the low latitude region and the polar regions with the data of the solaroccultation infrared spectrometers las boarding the satellite ohzora exosc and ilas boarding the satellite midori adeos, respectively.
Ozone o 3, or trioxygen, is a triatomic molecule consisting of three oxygen atoms. Download the introductory presentation ppt, 410 kb during the first kinetics lecture, we traced the efforts of atmospheric chemists to explain the depletion of ozone in the upper atmosphere. Environmental chemistry 401 carbon dioxide crosses the delicate proportion of 0. Ozone depletion consists of two related events observed since the late 1970s.
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