This layer absorbs between 93 and 99 per cent of the ultraviolet radiation from the sun. Ozone depletion consists of two related events observed since the late 1970s. Information is also provided regarding some of the most frequently asked questions as well as recent. 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. A key component of photochemical smog, ozone is formed by a complex reaction between nitrogen dioxide and hydrocarbons in the presence of sunlight. Approximately 90 percent of the atmospheres ozone occurs from 1018 km 611 miles to about 50 km about 30 miles above earths surface. May 14, 2020 view the latest status of the ozone layer over the antarctic, with a focus on the ozone hole. Click any map image to bring up a new page with a highresolution map. Pdf causes of ozone layer depletion and its effects on. The noaa stratospheric ozone webpage is a one stop website for access to realtime as well as historical stratospheric ozone products, descriptions of instruments used to detect ozone, and of the organizations involved in collecting and archiving stratospheric ozone data. The stratospheric ozone layer is earths sunscreen protecting living things from too much ultraviolet radiation from the sun. The earths ozone layer ozone layerthe region of the stratosphere containing the bulk of atmospheric ozone. It covers the entire planet and protects life on earth by absorbing harmful ultravioletb uvb radiation from the sun.
When cfc is released into the atmosphere, they mix with atmospheric. This radiation is dangerous to living organisms on earth. Click any map image to bring up a new page with a highresolution image. Schematic of the influence of ozonedepleting substances and climate change on the stratospheric ozone layer, and the influence of ozone changes on surface ultraviolet radiation. 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 o3 is a molecule made up of three atoms of oxygen o, and is mostly found. The sun propagates ultraviolet radiations which as an adverse effect on living beings.
Pdf there are many situations where human activities have significant effects on the environment. Information for policymakers and options for policy formulation. The ozone layer is a layer of ozone high up in the earth s atmosphere stratosphere, between approximately 10 kilometres and 50 kilometres above earths surface. The ozone layer stops most of the harmful ultraviolet rays, or uv rays, from hitting 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. The ozone layer is a region in the earths stratosphere that contains high concentrations of ozone and protects the earth from the harmful ultraviolet radiations of the sun. Conversely, changes in the climate of the earth could affect the behavior of the ozone layer, because ozone is influenced by changes in the meteorological conditions and by changes in the atmospheric composition that could result from climate change. The ozone layer is a deep blanket in the stratosphere made up of comparatively high concentration of the ozone. The ozone layer helps to protect life from harmful ultraviolet radiation. May 14, 2020 view the latest status of the ozone layer over the arctic.
The troposphere extends from the surface up to about 10 km in altitude, although this height varies with latitude. There are natural processes that create and destroy ozone in the stratosphere. In the 1970s, people all over the world started realizing that the ozone layer was getting thinner and that this was a bad thing. The stratosphere is the mass of protective gases clinging to our planet. 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 has been found that this protective ozone layer is getting depleted because of the presence of cfc chlorofluorocarbon compounds. Thankfully, the ozone layer protects us from most of the suns harmful uv rays. Ozone is unstable and decomposes to molecular oxygen. A dynamic equilibrium is maintained between the formation and decomposition of ozone.
In thunderstorms, ozone forms as a result of the high. It absorbs up to 9799% of uvlight less than the wavelength of 290nm. Experts blame ozonelayer depletion on manmade chem icals containing chlorine. 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. Causes of ozone layer depletion and its effects on human. Ozone and the ozone layer australia department of the. This ozone uv absorption is important to life, since it extends the absorption of uv by ordinary oxygen and nitrogen in air which absorb all wavelengths pdf atmospheric and climate sciences, 2016, 6, 1294 published online january 2016 i n s ci r es. It is considered to be a criteria pollutant in the tropospherethe lowermost layer of the atmospherebut not in the upper atmosphere, where additional information. The major issue is that the stratosphere will most probably cool in response to climate change. 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.
Good up high, bad nearby pdf, 2 pp, 91 kb ozone acts as a protective layer high above the earth, but it can be harmful to breathe. The exact amount of ozone varies, depending on the seasons and the location. The ozone layer is a natural layer of gas in the upper atmosphere that protects humans and other living things from harmful ultraviolet uv radiation from the sun. 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. Images, data, and information for atmospheric ozone ozone maps meteorology ozone facts multimedia education northern hemisphere view the latest status of the ozone layer over the antarctic, with a focus on the ozone hole. The gaps in the ozone layer over the polar region present a threat to humans, animals, and plants, because of the increase in uvb radiation reaching the surface of the earth. Ozone layer the ozone layer is basically naturally occurring gas in the region of stratosphere where ozone particles are accumulated 2. Nasa ozone watch images, data, and information for atmospheric ozone ozone maps meteorology ozone facts multimedia education southern hemisphere view the latest status of the ozone layer over the arctic. Ozone depletion is largely a result of manmade substances. Schlottmann, in information resources in toxicology fourth edition, 2009. While there are natural sources for all of these species, the concentrations of chlorine and bromine increased markedly in recent decades because of the release of large quantities of manmade organohalogen compounds. But through domestic and international action, the ozone layer is healing and should fully recover by about 2065.
Ozone layer definition is an atmospheric layer at heights of about 20 to 30 miles 32 to 48 kilometers that is normally characterized by high ozone content which blocks most solar ultraviolet radiation from entry into the lower atmosphere. The ozone layer is a layer of ozone high up in the earths atmosphere stratosphere. Ozone layer is also naturally broken down but there is a balance between its formation and natural depletion. Ozone layer depletion is one of the major environmental issues which is getting thinner day by day as a result of increasing pollution. Ozone is formed from dioxygen by the action of ultraviolet uv light and electrical discharges within the. Ozone holes are popular names for areas of damage to the ozone layer.
It is an allotrope of oxygen that is much less stable than the diatomic allotrope o 2, breaking down in the lower atmosphere to o 2. The sun renews the ozone and natural chemicals in our atmosphere destroy it. Although ozone is present in small concentrations throughout the atmosphere, most around 90% exists in the stratosphere, a layer 10 to 50 kilometres above the earths surface. It will take generations before we know how the experiment turned out.
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 odour of ozone around electrical machines was reported as early as 1785. 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. The latter phenomenon is referred to as the ozone hole. This layer absorbs 9399% of the suns high frequency ultraviolet light, which is potentially damaging to life on earth 1. Ozone layer depletion cause, effects, and solutions. Sep 30, 2014 ozone is a colorless gas mainly found in earths stratosphere. Ozone layer simple english wikipedia, the free encyclopedia. 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. The ozone layer prevents most ultraviolet uv and other highenergy radiation from penetrating to the earths surface. List of books and articles about ozone layer online. The ozone layer is an invisible layer of protective gases that circle the earth.
It forms a protective layer that absorbs harmful ultraviolet light from the sun. The hole occurs over antarctica because the extreme cold helps the very high clouds characteristic of that area form tiny ice particles of water and nitric acid, which. Ozone depletion facts and information national geographic. It is formed by the reaction of various air pollutants in the presence of sunlight. A seasonal decrease, or hole, in the ozone layer above antarctica, first discovered in 1982 and reported in 1985, was the first confirmation of a thinning of the layer. Ozone is a form of naturally occurring gas and 90% of our planets ozone is in the stratosphere. Introduction the ozone layer is a layer in earths atmosphere which contains relatively high concentrations of ozone o3. Ozone is a colorless gas mainly found in earths stratosphere. Information is also provided regarding some of the most frequently asked. Unfortunately, this gives them plenty of time to find their way to the ozone layer. One chlorine molecule from a cfc can destroy up to 100,000 ozone molecules. After thinning at alarming rates in the 1980s and 90s, the ozone layer over antarctica is starting to recover. 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.
The lowest layer, the troposphere tropospherethe region of the atmosphere closest to the earth. Find out what caused the ozone hole, and how the 1989 montreal. Ozone in the stratospherea layer of the atmosphere between 15 and 50. The ozone layer is the common term for the high concentration of ozone that is found in the stratosphere between 15 and 30km above the earths surface. Watch a movie of the daily progression through a season or the annual progression of the. The ozone layer is present about 2030km above the earth surface.
We seem to have avoided a future where there is no protective ozone. The stratosphere gets its name because it is stratified, or layered. Ozone, o 3, triatomic allotrope of oxygen a form of oxygen in which the molecule contains three atoms instead of two as in the common form that accounts for the distinctive odour of the air after a thunderstorm or around electrical equipment. Basic ozone layer science ozone layer protection us epa. Ozone is an irritating, corrosive, colorless gas with a smell something like burning electrical wiring. The montreal protocol is an international environmental agreement with universal ratification to protect the earths ozone layer by eliminating use of ozone depleting substances ods, which would otherwise allow increased uv radiation to reach the earth, resulting in higher incidence of skin cancers and eye cataracts, morecompromised immune. The earths atmosphere is composed of several layers. The emission of ozone depleting substances has been damaging the ozone layer.
As a result the total amount of ozone remains constant. In 1985, an extreme depletion of ozone over antarctica was discoveredthe socalled antarctic ozone hole. Ozone is also formed during thunderstorms, in water falls and allthough this is a less natural process in photochemical smog which forms in summer. This natural protective shield has been damaged by the worldwide use of ozonedepleting. Watch how ozone concentrations in the stratosphere have changed from 1979 through 2018. Ozone is also used commercially as a bleaching agent and to purify municipal. Ozone layer introduction the ozone layer refers to the ozone within stratosphere, where over 90% of the earths ozone resides. This publication provides basic information about groundlevel and highaltitude ozone. Chapter 3 gives a brief overview on the major factors determining the uvclimate and the changes in the uv radiation levels in europe that occurred over the past.
Ozone layer protection european commission europa eu. The exact amount of ozone that can be found varies, the seasons influence it. The ozone layer is a thin layer that acts as a protecting shield by absorbing harmful uv radiations. Satellite instruments monitor the ozone layer, and we use their data to create the images that depict the amount of ozone. Ozone layer definition of ozone layer by merriamwebster. Ozone, a form of oxygen consisting of three atoms of oxygen instead of two, is considered an air pollutant when found at ground levels and is a major component of smog. The ozone layer can be depleted by free radical catalysts, including nitric oxide no, nitrous oxide n 2 o, hydroxyl oh, atomic chlorine cl, and atomic bromine br. The word ozone means smelly in greek because the gas has a strong odor.
Apr 18, 2019 the ozone layer helps to protect life from harmful ultraviolet radiation. However, the ozone layer is destroyed by manmade chemicals known as ozonedepleting substances ods. This website addresses stratospheric ozone issues, including the science of ozone depletion, epas regulatory approach to protecting the ozone layer, epa. This layer absorbs the radiations and prohibits them from entering the outer surface of the earth. When highenergy ultraviolet rays uvc strike an oxygen. Ozone is harmful at ground level but high up the atmosphere ozone layer plays a vital role in the protection of all living beings. Protecting the ozone layer department of the environment. In the layer surrounding the earths surface, the troposphere, ground level or bad ozone is an air pollutant that is a key ingredient to. Ozone layer damage is more like a really thin patch than a hole. Cfc molecules are highly stable and can last for up to 100 years. Ninety percent of the atmospheric ozone is in the earths stratosphere the altitude starting at six to 11 miles 9. The ozone layer is one layer of the stratosphere, the second layer of the earths atmosphere. Causes, effects and solutions of ozone layer depletion.
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