The increased use of humanproduced gases such as chlorofluorocarbons cfcs has led to a magnified springtime depletion of the protective ozone layer at both earths poles, especially over antarctica, a phenomenon well known as the ozone hole. This page provides information on compounds recognized as ozone depleting substances ods odsa compound that contributes to stratospheric ozone depletion. It absorbs solar ultraviolet radiation, which heats the stratosphere. Ozone layer depletion causes, effects and solutions. Causes of ozone layer depletion and its effects on human.
In 1985, the scientists published an article in nature announcing that stratospheric ozone over antarctica was reduced 40% in september, the end of the austral winter. Experts blame ozonelayer depletion on manmade chem icals containing chlorine and. Money and time are being spent on ozone repair, but the problem still exists. However, it has been postulated that a potential effect of hfcs on stratospheric temperatures may augment the reactions that deplete stratospheric ozone 2. Ozone near the ground is a pollutant, but in the upper stratosphere, it forms a protective layer around the planet that absorbs ultraviolet sunlight, thereby protecting all life from the harmful effects of that radiation. Atmospheric ozone has two effects on the temperature balance of the earth. Ozone depletion and climate change, or ozone hole and global warming in more popular terms, are environmental challenges whose connections have been explored and which have been compared and contrasted, for example in terms of global regulation, in various studies and books. Hcfcs hydrochlorofluorocarbons differ from cfcs in that only. The ozone layer refers to a region of earths stratosphere that absorbs most of the suns uv radiation. Hfcs and ozone depletion over 20 years ago it was established that hfcs have no chemical effect on stratospheric ozone 1. Ozone is harmful at ground level but high up the atmosphere ozone layer plays a vital role in the protection of all living beings.
This depletion makes humans more vulnerable to the uvb rays which are known to cause skin cancer as well as other genetic deformities. The ozone layer lies approximately 1540 kilometers 1025 miles above the earths surface, in the stratosphere. The ozone layer thus plays an important role by preventing the harmful uv radiations from penetrating into the earths lower atmosphere the troposphere. While several substances were addressed, chcs and hcfcs were the main ones that the international. The use of cfcs is one of the main reasons for the depletion of the layer. What is important to keep in mind is the fact that prevention of ozone layer depletion is so very important because it directly affects the well being of the people. When did we realize ozone depletion was an issue, and how did we fix it. 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. Notice the croissant of high ozone concentrations formed when the antarctic vortex blocks the southerly migration of ozone formed in the tropics. 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.
Huijbregts1 1 department of environmental science, radboud university nijmegen, the netherlands z. Causes, effects and solutions of ozone layer depletion. Generally, we find thinning or depletion of the ozone layer to the extent of ozone hole creation over the southern pole i. Ozone depletion is affecting the human health and environment negatively, as it allows the penetration of uv radiations to reach the earth. Measured infrared absorption data are also combined with the lifetime to show that the 20. Ods include chlorofluorocarbons cfcs, hydrochlorofluorocarbons hcfcs, halons, methyl bromide, carbon tetrachloride, hydrobromofluorocarbons, chlorobromomethane, and methyl chloroform. This ambitious book successfully brings together all aspects necessary for an indepth understanding of the interaction of stratospheric ozone depletion and climate change. The thinning of the ozone layer has increased the risk that australians already face from overexposure to uv radiation from an outdoor lifestyle. Health and environmental effects of ozone layer depletion. Ozone depletion also explains much of the observed reduction in stratospheric and upper tropospheric temperatures. The thinning or reduction of ozone depletion is most prominent in the polar regions, especially over antarctica. Aerosols are common, convenient, and harmless, right. 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 deodorant.
The ozone layer absorbs much of the incoming solar ultraviolet radiation uvr and thus offers substan. When the depletion of ozone layer becomes a phenomenon for our survival on this earth, s cientists and people from different countries come forward to stop this depletion by taking necessary steps. Jan 20, 2010 the montreal protocol is an international agreement to address the causes of ozone depletion. It was agreed on 16 september 1987, and entered into force on 1 january 1989. This layer serves as a shield that protects the earth from harmful ultraviolet radiation from the sun. Ozone layer depletion cause, effects, and solutions. Ozone ozone is a simple molecule of three oxygen atoms and it is present in the two lowest layers of the atmosphere troposphere and stratosphere. Dedicated at the university of california, irvine on april 18, 2017. The core contains 25 general knowledge questions relating to stratospheric ozone depletion, rules and regulations of the clean air act, the montreal protocol, refrigerant recovery, recycling and reclaiming, recovery devices, substitute refrigerants and oils, recovery techniques, dehydration, recovery cylinders, safety, and shipping.
Ozone depletion consists of two related events observed since the late 1970s. Global warming and ozone layer depletion are two different problems see the sidebar misconceptions about global atmospheric change on page 95. Ozone depletion and global warming potentials of cf3i. Our powerpoint presentation about ozone depletion, its effects and its causes. Make your own animated videos and animated presentations for free. Ozone o3 is a stratospheric layer that plays important role in providing support to humans for their survival. These chemicals are found in cleaning agents, aerosols, insulating foam, and refrigerants. Oxygen can combine into molecules with three atoms, however, which are called ozone.
It contains high concentrations of ozone o3 relative to other parts of the atmosphere. Ozone layer protection european commission european union. The antarctic ozone hole, as it came to be known, made depletion of. Life on earth has been protected for thousands of years with a vital layer of poison in the atmosphere. A class of widely used chemical coolants known as hydrofluorocarbons hfc contributes to ozone depletion by a small but measurable amount, countering a decadesold assumption, according to a new nasa study. There is a steady decline of about 4% in the total volume of ozone in earths stratosphere. Peering into the ozone hole science mission directorate. One active volcano, can emit more allegedly ozone depleting gases than all manmade sources combinedtheres still enough ozone. Update on ozonedepleting substances odss and other gases of. The depletion of ozone layer has trickle down effects in the form of global warming, which in turn leads to melting of polar ice, which will lead to rising sea levels and climatic changes around the world. Ozone in the lower atmosphere contributes to global warming and climate change.
Chlorofluorocarbons and ozone depletion american chemical. Blue denotes low ozone concentrations and yellow and red denote higher levels of ozone. Case study depletion of ozone in the atmosphere the work of g. The thinning is most pronounced in the polar regions, especially over antarctica. This layer absorbs the radiations and prohibits them from entering the outer surface of the earth. It is an essential factor for many global, biological and environmental phenomena. The ozone layer is mainly found in the lower portion of the stratosphere. Earth enjoys many advantages among the planets in the solar system, from its moderate temperatures and the existence of water and oxygen to its layer of ozone molecules that protect its inhabitants from the suns harmful energy. The natural distribution of ozone around the earth is. Effects of ozone depletion ozone depletion is affecting the human health and environment negatively, as it allows the penetration of uv radiations to reach the earth. Since india already receives high doses of ultraviolet uvb radiation, and is at the threshold go to speak, effects of ozone layer depletion. The ozone layer acts like a shield in the upper atmosphere the stratosphere, to protect life on earth from harmful ultra violet uv radiation. The vienna convention for the protection of the ozone layer is a multilateral environmental agreement signed in 1985 that provided frameworks for international reductions in the production of chlorofluorocarbons due to their contribution to the destruction of the ozone layer, resulting in an increased threat of skin cancer. Ozone depletion facts and information national geographic.
Cfcs build up and block the filtering effects of the ozone layer c. The emission of ozonedepleting gases are threatening the earths ozone layer. Title vi for stratospheric ozone protection, signed into law. If you need to print pages from this book, we recommend downloading it as a pdf. Vice versa, the depletion of stratospheric ozone has caused important changes in tropospheric climate and will continue to do so for decades to come. The assessment documents the advances in scientific understanding of ozone depletion reflecting the thinking of the many international scientific experts who. Essay ozone depletion is a serious problem presently facing the world. By 1985, the globe had already seen advancements in the scientific understanding of ozone depletion and its impacts on human health and the environment. The research described in the short paper, however, fell like a scientific bombshell, one whose repercussions would be felt around the world. The reason behind ozone layer depletion is mainly due to the extensive use of ozone depleting substances ods.
Image of the recordsize ozone hole taken by nasa satellites on september 9, 2000. Ozone depletion is primarily caused by human activities. The antarctic ozone hole, as it came to be known, made depletion of the ozone layer a real and present danger to lawmakers and the public at large. Chapte r ozone depletion potentials, global warming. Stratospheric ozone depletion, ultraviolet radiation and health. Introduction under the montreal protocol on substances that deplete the ozone layer, article 7 of the protocol. Unfortunately, this book cant be printed from the openbook. The causes, mechanism and bioeffects of ozone layer depletion on humans were addressed. Let us have a detailed look at the various causes and effects of ozone layer depletion. Pdf causes of ozone layer depletion and its effects on. Predictions of significant increases in the incidence of skin cancer resulting from continued use of cfcs spurred international action. Find out what caused the ozone hole, and how the 1989 montreal protocol sought to put an end to ozone depletion. Ozone depletion is largely a result of manmade substances. They are usually used as a coolant in refrigerators and.
The language is dry and academic, as is appropriate for the abstract of a scientific paper in the prestigious journal nature. B dobson and other scientists in measuring concentrations of chloride and ozone in the atmosphere g. Ozone layer depletion increases the amount of uvb that reaches the earths surface. Phasing out ozone depleting substances to protect the ozone layer ozone layer the region of the stratosphere containing the bulk of atmospheric ozone. Pdf chlorofluorocarbons cfcs and their effect on the. Project report on ozone depletion environmental pollution. Ozone depletion free download as powerpoint presentation. What are the causes and effects of ozone depletion.
The ozone layer helps to protect life from harmful ultraviolet radiation. Cfcs and ozone depletion nature and community mother. Protection against depletion of stratospheric ozone by. The treaty is structured around several groups of halogenated hydrocarbonsthat deplete stratospheric. But ozone depletion and climate change are linked in many other ways as well,particularly through. The depletion of the ozone describes two closely related but distinct phenomena which have been repeatedly observed since the latter 1970s. Laboratory and epidemiological studies demonstrate that uvb causes nonmelanoma skin cancer and plays a major role in malignant melanoma development. Stratospheric ozone depletion through catalytic chemistry involving manmade chloro. Pdf there are many situations where human activities have significant effects on the environment.
Common coolants contribute to ozone depletion nasa. Global ozone research and monitoring project wmo library. The ozone layer protects humans, animals, and plants from harmful ultraviolet rays. This study was conducted at university of gujrat during 20142015 as a term paper for master of philosophy. How do chlorofluorocarbons cfcs contribute to ozone depletion. Introduction under the montreal protocol on substances that deplete the ozone layer, article 7 of the protocol requires all parties, both developing countries also called article 5 countries and developed countries. Protecting the ozone layer department of the environment. The troposphere extends from the surface of the earth upto 12 km and stratosphere extends upto about 50 km from the surface of the.
The main effect of ozone depletion is an increase in uvb rays reaching the earths surface causes. Global warming is caused by the greenhouse effect, which is essential to life as we know it on planet earth. 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. These radiations can cause severe diseases in humans such as skin cancer, eye damage and genetic mutations etc 9. The ozone layer was discovered in 19 by the french physicists charles fabry and henri buisson. Ozone depletion and climate change are linked in a number of ways, but ozone depletion is not a major cause of climate change. Humans have introduced gases and chemicals into the atmosphere that have rapidly depleted the ozone layer in the last century. For example, this theory neither predicted, nor can explain the existence of the ozone hole over antarctica another new theory that had to be manufactured to explain that. Technical report on stratospheric ozone depletion this report has been prepared by rivm, eftec, ntua and iiasa in association with tme and tno under contract with the environment directorategeneral of the european. Ozone depletion and global warming overview page 1 of 5 halocarbons are chemical compounds containing carbon, one or more halogens, and sometimes hydrogen. The severe depletion of the ozone layer in any particular area is called ozone hole.
Ozone layer depletion is one of the major environmental issues which is getting thinner day by day as a. The ozone depletion theory of global warming provides, for the first time, a clear, straightforward explanation for observations not easily explained by greenhousegas theory. Ozone depletion ozone depletion chlorofluorocarbon. Ozonedepleting substances ozone layer protection us epa. Areas of protection and environmental mechanisms covered. 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. Most ozone is found in the stratosphere upper part of the atmosphere, more than 10 to 16 kms from the surface of the earth. Depletion of o3 can increase uv radiation entering earth surface. We do these things almost automatically, not really even thinking about it. As a result, there has been a general thinning of the ozone layer over most of the globe, including between five to nine per cent depletion over australia since the 1960s. Ozone depletion potentials odps were a very important measure in the formulation of the montreal protocol and its amendments. Scientific assessment of ozone depletion montreal protocol.
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. All of us are aware of how the concern related to depletion of ozone layer and the ozone hole, which also led to the ban of many chemicals such as the chlorofluorocarbon cfc. There have been several concerns about ozone depletion. The sun propagates ultraviolet radiations which as an adverse effect on living beings. Understanding that global warming is caused by ozone depletion, not greenhouse gases, has major implications for investments in energy. Vienna convention for the protection of the ozone layer. Gwps including indirect effects of ozone depletion have been estimated fo r a variety of halocarbons cfcs, halons, hcfcs, etc. There are many situations where human activities have. Cfcs and ozone depletion reduce ozone depletion and environmental pollution by decreasing your use of common products with harmful chlorofluorocarbons, and learn more about the alternatives that. Cfcs destroy the ozone in the stratosphere 15 20 km above the earths surface ozone concentrations are measure in dobsen units, 1 dobsen unit represents 1 molecule of o 3 for every 1 billion air molecules ozone loss is greatest over antarctica where the ozone depletion has been recorded and is commonly referred to as the ozone hole. The problems and causes associated with ozone depletion arise from human activities. Jun 16, 2014 professor davis gives a short explanation of how chlorofluorocarbons also known as cfcs deplete the earths ozone layer.
The ozone layer is a region in the stratosphere where ozone is highly concentrated. Some halocarbons ozone depleting substances, or odss deplete the ozone layer, while others greenhouse gases, or ghgs are thought to contribute to global warming. Global collaboration and regulation aims to reduce the emissions. Progress report 2003 united nations environment programme, environmental e. What we all need to understand is the idea that we all are going to have to face the repercussions of ozone layer depletion. Stratospheric ozone depletion zoran steinmann1, mark a. The advent of chlorofluorocarbons, or cfcs, threatened the ozone layer and the survival of. The ozone layer is a region of the stratosphere containing ozone, or o3 gas. Ozone hole ozone depletion at south pole polar vortex and ozone depletion are two distinct but related phenomena. Ozone layer depletion causes, effects and solutions 7. Amid predictions that a cataclysmic depletion of the ozone layer would occur if production of chlorofluorocarbons cfcs. If any of the axioms and assumptions underlying the ozone depletion theory are proven wrong, the whole edifice falls.
The vienna convention for the protection of the ozone layer. Ozone layer is an international treaty designed to protect the ozone layerby phasing out the production of numerous substances that are responsible forozone depletion. Depletion of stratospheric ozone o3, as commonly known as the hole in the ozone layer, is an issue of international concern. The net gwps of halocarbons depend strongly upon the effectiveness of each compound for ozone destruction.
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