Twenty questions and answers about the ozone layer. Find, read and cite all the research you need on researchgate. Ozone depletion is largely a result of manmade substances. Oxygen can combine into molecules with three atoms, however, which are called ozone.
Nearly 90% of earths ozone is in the stratosphere and referred to as the ozone layer. Normal ozone ozone layer depletion and its effects. The main things that lead to destruction of the ozone gas in the ozone layer. Ozone layer depletion cause, effects, and solutions. If each chlorine atom released from a cfc molecule destroyed only one ozone molecule, cfcs would pose very little threat to the ozone layer. Achievements in stratospheric ozone protection ozone layer. When highenergy ultraviolet rays uvc strike an oxygen molecule o. Sep 30, 2019 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. It sets binding obligations for countries to phase out production of all the major ozone depleting substances. Ozone layer destruction of the ozone layer the causes. The ozone layer helps to protect life from harmful ultraviolet radiation. In 1987, to address the destruction of the ozone layer, the international community established the montreal protocol on ozone depleting substances. The latter phenomenon is referred to as the ozone hole.
Reading skills get sharpened by unseen passage reading comprehension test. Depletion of ozone layer is also causing the problem of food shortage to humans. 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. Others say there is no abnormality at all, that it is just natural warming. Causes, effects and solutions of ozone layer depletion. Ozone layer introduction the ozone layer refers to the ozone within stratosphere, where over 90% of the earths ozone resides. In the last thirty years, it has been discovered that stratospheric ozone is depleting as a result of anthropogenic pollutants. Interactions between climate change and stratospheric ozone may delay recovery of the ozone layer by 1520 years 5. Learn what cfcs are, how they have contributed to the ozone hole, and how the 1989 montreal. Causes of ozone layer depletion and its effects on human. In laboratory studies scientists are able to discover and evaluate individual chemical reactions that also occur in the stratosphere. There are a number of chemical reactions that can deplete stratospheric ozone. These processes regulate a balance of ozone and form the ozone layer. 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.
Uv radiations are disturbing developmental and physiological processes which is decreasing the productivity of crops. Chlorofluorocarbons cfcs have been identified as the main cause of the destruction to the ozone layer, but there are also compounds containing bromine, other halogen compounds and also nitrogen oxides which cause damage. The thinning is most pronounced in the polar regions, especially over antarctica. 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. But the one and the most important reason for ozone layer depletion is the production and emission of. Ozone layer depletion causes, effects and solutions 7. Find out what caused the ozone hole, and how the 1989 montreal protocol sought to put an end to ozone depletion. Further, that loss of ozone itself augments the cooling of the stratosphere. Pdf causes of ozone layer depletion and its effects on. Ozone layer depletion is the thinning of the ozone layer present in the atmosphere.
The minimum is a conse quence of the ozone hole, which describes the widespread chemical destruction of ozone by ozonedepleting substances. The ozone depletion process replacing lost ozone in the stratosphere the idea is sometimes put forth that humans could compensate for lost global stratospheric ozone by replacing it. Feb 12, 2018 far above earths surface, the ozone layer helps to protect life from harmful ultraviolet radiation. We cant make enough ozone to replace whats been destroyed, but provided that we stop producing ozonedepleting substances, natural ozone production reactions should return the ozone layer to normal levels by about 2050. Update on ozonedepleting substances odss and other gases of. Mar 21, 2020 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 earths stratospheric ozone layer plays a critical role in absorbing ultraviolet radiation emitted by the sun. Achievements in stratospheric ozone protection this report describes the achievements of the people, programs, and organizations that are working to protect the earths ozone layer. Approximately 90 percent of the atmospheres ozone occurs from 1018 km 611 miles to about 50 km about 30 miles above earths surface. 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. Ozone is unstable and decomposes to molecular oxygen.
The key process control parameters are dose, mixing, and contact time. But many researchers do not agree with these predictions,14 and express their. It was the first international treaty to be signed by all countries of the world and is considered the greatest environmental success story in the history of the united nations. Ashworth abstract there has been a lot of discussion about global warming.
The amounts of ozone in the stratosphere vary naturally throughout the year as a result of production and destruction processes, and as a result of winds and other transport processes that. This passage is all about the ozone layer and the ozone layer restricts. The ozone layer, in the stratosphere, is where about 90% of the ozone in the earth system is found. Some say anthropogenic carbon dioxide co 2 emissions caused the earth to warm. Understanding stratospheric ozone depletion scientists learn about ozone destruction through a combination of laboratory studies, computer models, and stratospheric observations. But ozone makes up only one to ten out of every million molecules in the ozone layer. This layer absorbs 9399% of the suns high frequency ultravioletlight, which is potentially damaging to life on earth. 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. Third, depletion of stratospheric ozone and global warming due to the build. Cfc destruction of ozone major cause of recent global warming. It describes the benefits of these achievements, including healing the ozone layer, saving lives, and protecting the planet. According to t he chemical model fo r ozone destruction pr oposed about 20.
Dec 14, 2017 scientists are closely monitoring positive signs of recovery of the earths stratospheric ozone layer, which is depleted by the use of chemicals called chlorofluorocarbons cfcs for a range of. Ozone depletion and climate change environment canada. One of the main reasons for the widespread concern about depletion of the ozone layer is the anticipated increase in the amounts of ultraviolet radiation received. It has been found that this protective ozone layer is getting depleted because of the presence of cfc chlorofluorocarbon compounds. Ozone could be manufactured, stored, transported to the stratosphere, and released in depleted regions.
Evidence of ozone depletion in the stratosphere began to appear in the 1980s. The unintentional experiment started in the late 1920s, when thomas midgley jr. Apr 18, 2019 the ozone layer helps to protect life from harmful ultraviolet radiation. Chemistry of the ozone layer there are natural processes that create and destroy ozone in the stratosphere. Ozone absorbs a band of ultraviolet radiation called uvb. 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.
The net or overall reaction is that of atomic oxygen with ozone, forming two oxygen molecules. The destruction of ozone in cycle 1 involves two separate chemical reactions. The ozone layer is a deep blanket in the stratosphere made up of comparatively high concentration of the ozone. Questions and answers about the environmental effects of the ozone layer depletion and 4 climate change. The amount of ozone that will dissolve in wastewater at a. Ozone layer depletion is one of the major environmental issues which is getting thinner day by day as a result of increasing pollution. Ozone depletion consists of two related events observed since the late 1970s.
The rest of the molecules are mostly nitrogen and oxygen, like the air we breathe. An ozone disinfection system strives for the maximum solubility of ozone in wastewater, as disinfection depends on the transfer of ozone to the wastewater. 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. Humans have been depleting the ozone layer with chemical products. Without human intervention, the stratospheric ozone layer would be produced and destroyed through natural processes. Atmospheric concentrations of most ozonedepleting substances peaked, or their. When cfc is released into the atmosphere, they mix with atmospheric. There isnt much of it, but ozone is powerful, able to block the most. Destruction of the ozone layer the ozone layer is a layer in earths atmosphere which contains relatively high concentrations of ozone o3. Pdf there are many situations where human activities have significant effects on the environment. National aeronautics and the ozone hole space administratio n.
We provide reading comprehension exercises with answers. Nearly 500 organizations, teams, and individuals from 40 countries have received stratospheric ozone protection awards for their exceptional leadership, personal dedication, and technical achievements. Stratospheric ozone depletion, ultraviolet radiation and health. Questions and answers about the environmental effects of the. Timeline of stratospheric ozone depletion and observations.
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