Four ways the ozone hole is linked to climate, and one way it. But the one and the most important reason for ozone layer depletion is the production and emission of chlorofluorocarbons cfcs. Apr 14, 2017 the ozone hole is an area where the amount of ozone in the upper atmosphere is much lower than normal. The ozone hole now occurs every year in antarctica between the months of september and november, which is the south poles springtime. Oct 18, 2018 this activity uses ozone watch to explore seasonal ozone hole data.
There are also springtime polar tropospheric ozone depletion. In addition, the sources of ozone depleting substances and the mechanism of ozone depletion have been. 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 hole is not really a hole but a thinning of the ozone layer over the south polar region. Useful for students looking to get great grades in school. View the latest status of the ozone layer over the antarctic, with a focus on the ozone hole. Marusek 24 february 2005 introduction the earth is surrounded by a thin layer of ozone in the middle atmosphere stratosphere about 25 kilometers above the earths surface. Students will be able to differentiate between o2 oxygen and 03 ozone. It is produced at ground level through a reaction between sunlight and, e. The purpose of the activity is to construct a model that will provide students with a visual representation of. Pdf impact of stratospheric ozone hole recovery on. But the best thing about the mending of the ozone hole may be that it serves as a reminder that international efforts to. The gaping hole in the ozone layer of the atmosphere over the antarctic was caused primarily by high concentrations of ozonedepleting chemicals called cfcs. The ozone hole is defined geographically as the area wherein the total ozone amount is less than 220 dobson units.
The hole in the ozone layer over antarctica became an international cause for concern in the latter half of the 20th century, but researchers point out that the issues relating to ozone levels are. The words ozone hole are more oriented towards the general public, which may justify a separate article using more mundane language. The impact of stratospheric ozone hole recovery on antarctic. The thinning is most pronounced in the polar regions, especially over antarctica. In fact, the researchers believe the ozone hole has shrunk by more than 4 million square kilometers. Ozone was a hot topic among scientists an august 1985 meeting in salzburg, austria, a few days after pawan bhartia presented the first satellite image of the ozone hole. Consequently, the level of ozone protecting us from ultraviolet radiation decreases. Please contact the director of the ozone and synthetic gas team ph. When the ozone hole was discovered, it became a worldwide sensation.
The larger holes cause ozone to leak out at a faster rate than ozone is being created. This year the antarctic ozone hole got a head start with greater then average chemical ozone losses since the mid of august. At present, the average ozone levels are higher now than they were in the 1960s. How and why are measurements of ozone taken from space. Sep 12, 2011 the edge of the ozone hole passed over the tip of south america around september 26 to 28. Information about ozone hole in the dictionary, synonyms and antonyms. This timeline highlights the average area of the ozone hole between september 7th and october th as observed by nasa spacedbased instruments see. Ultra violet rays have the capability to destroy plants and animals and can cause skin. Ozone layer depletion is one of the major environmental issues which is getting thinner day by day as a result of increasing pollution. The story of the ozone hole although often referred to as the ozone hole, it is really not a hole but rather a thinning of the ozone layer in the stratosphere. The vast hole in the ozone was discovered by scientists in the 1980s, who upon discovering the dramatic loss in ozone cover, set to work determining a primary cause.
In the 1980s, this frightening prospect motivated the scientific community and policy makers of the world to address the issue of cfc production, which resulted in the 1987 montreal protocol. The gaping hole in the ozone layer of the atmosphere over the antarctic was caused primarily by high concentrations of ozone depleting chemicals called cfcs. The vast hole in the ozone was discovered by scientists in the 1980s, who upon discovering the dramatic loss in. The ozone depletion has led to a worldwide concern as the thinning protective coat over earth is letting harmful ultraviolet light pass. However, ozone and cfcs contribute very little to climate change compared to carbon dioxide. Should we still be concerned about the ozone layer. I recently read a news article about the ozone hole. Uv rays can cause sunburn and damage the dna, the ozone layer absorbs most of the harmful radiations and protects us. The antarctic ozone hole reached its annual peak size on sept.
If there was any place on the earth where a thinning would be safe, antarctica is the spot. Is it true that the ozone layer protects humans, animals, and plants. The state of scientific understanding regarding the ozone depletion issue has advanced in recent years as a result of the concerted efforts of hundreds of scientists worldwide. The latter phenomenon is referred to as the ozone hole. The observed average amount of ozone during september, october, and november over the british antarctic survey station at halley, antarctica, first revealed notable decreases in the early 1980s, compared with the preceding data obtained starting in. In attendance were donald heath, who initiated the ozone measurement program at goddard in the late 1960s, and the late sherry rowland, who later received the noble prize for. Ozone hole refers to answer this multiple choice objective question and get explanation and result. We will use the term hole in reference to the seasonal thinning of the ozone layer. Few years ago ozone holes are also discovered in arctic region. Overall, the 2014 ozone hole is smaller than the large holes of the 19982006 period, and is comparable to 2010, 2012, and 20. Ozone hole healing could cause further climate warming date. Ozone also occurs in very small amounts in the troposphere. Now, the size of ozone hole over antarctica is estimated to be about 30 million sq.
October 15,2011 noaa antarctic ozone hole reaches annual maximum at 25 million square kilometers about 9. How the ozone hole forms the ozone hole is not really a hole but a thinning of the ozone layer over the south polar region. The ozone hole is the region over antarctica with total ozone of 220 dobson units or lower. Earth has two ozone holes, one in antarctica which is larger than the one in the arctic during summer in the northern hemisphere the arctic ozone hole is sporadic and seasonal. Causes, effects and solutions of ozone layer depletion. The main cause of o3 getting changed to o2 is the presence of cfcs in the upper atmosphere. The ozone layer is a deep blanket in the stratosphere made up of comparatively high concentration of the ozone. The vortex is more distorted than last year increasing the sunlit area. Ozone hole ozone hole is created in the region where ozone layer has been depleted. The ozone hole occurs during the antarctic spring, from september to early december, as strong westerly winds start to circulate around the continent and create an atmospheric container. Ozone is a minor constituent of the stratosphere 110 ppm. Ozone holes are first discovered in antarctica in 1970.
The ozone problem is back and worse than ever james anderson, the winner of a smithsonian american ingenuity award, has discovered the alarming link between climate change and ozone loss. Normal ozone ozone layer depletion and its effects. The term ozone hole is applied when the depletion level is below 200 dobson unit d. The ozone layer is the earths natural sunscreen that protects humans, plants and animals by filtering out harmful uvb radiation. Due to this, it is also taking a toll on our health and the environment. The ozone layer helps in absorbing the ultraviolet uv rays of the sun which are harmful to human beings. The largest singleday ozone hole ever recorded by satellite was 29. What is an ozone hole and causes and effects of ozone. 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. People who have no idea what they are talking about. Impact of stratospheric ozone hole recovery on antarctic climate article pdf available in geophysical research letters 358 april 2008 with 129 reads how we measure reads. A study by bernese climate researchers has now shown that it even affects precipitation in. Ozone hole w notes free download as powerpoint presentation. The ozone hole is actually not a hole but a thinning.
Scribd is the worlds largest social reading and publishing site. Every year, since at least 1978, there is a sudden, rapid decrease in the stratospheric ozone levels at the end of the antarctic winter. The main source of these halogen atoms in the stratosphere is photodissociation of man. The ozone hole happens when ozone molecules high in the atmosphere are broken apart and the pieces form oxygen molecules. About the reports these reports are issued by csiro each year when the antarctic hole forms in the southern hemisphere spring. Ozone hole pdf the thinning of the ozone oracle 10g grid architecture pdf layer is caused by a chemical reaction where man. In the measurements made in recent times significant reductions in ozone concentrations in the layer, with special. What causes the ozone hole, and is it getting bigger. Note the growth in intensity and area of the southern ozone hole ozone deficits are blue, which heals several decades into the 21st century. This activity is associated with studies of surface ozone but can serve studies of stratospheric ozone as well. The hole in the ozone layer was perhaps the worst example of mankinds impact on the planet, but a worldwide campaign against ozonedepleting chemicals has helped repair most of the damage.
In the 1980s, scientists noticed that the ozone layer over the south pole was becoming much thinner than usual. Students will be able to describe where in the atmosphere the ozone layer is located. Ozone hole cause and effects free download as powerpoint presentation. Ozone hole definition is an area of the ozone layer as near the south pole that is seasonally depleted of ozone. The good news about the ozone hole is even better than you. The amounts of ozonedepleting substances grew rapidly in our atmosphere in the 80s and early 1990s, but had stopped growing in late 90s because of the 1987 montreal protocol. 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. Current measurements indicate the size of the ozone hole is about five times the size of california. In addition, ozone gas in the troposphere below the ozone layer and chlorofluorocarbons cfcs, which have helped cause the ozone hole, are greenhouse gases, which means they trap heat in the earths atmosphere. The hole in the ozone layer is daintier than usual this year, but its still a cause for concern. Antarctic ozone hole summary reports department of. During this time, ozone levels over most of antarctica are reduced by about 60% of their usual amount.
Ozone hole is the area of the earths atmosphere where abnormal reductions of ozone occur, it is an annual phenomenon observed during the spring in the polar regions and is usually followed by a recovery during the summer. The details of polar ozone hole formation differ from that of midlatitude thinning, but the most important process in both is catalytic destruction of ozone by atomic halogens. The springtime antarctic ozone hole is a new phenomenon that appeared in the early 1980s. Click any map image to bring up a new page with a highresolution image. Eric nielsen, 3 7 william neff2 8 1cooperative institute for. The ozone destroyed by manmade emissions is comparable or more than the amount destroyed by natural processes. Ozone hole definition of ozone hole by merriamwebster. Apr 27, 2020 view the latest status of the ozone layer over the antarctic, with a focus on the ozone hole.
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. The ozone hole was super scary, so what happened to it. View animation this plot of ozone concentration by latitude and altitude shows the net gain oranges and reds and net loss of ozone from years 197584 to 206069. The hole in the ozone layer above antarctica has more farreaching consequences than previously assumed. Representatives from 23 nations met in 1987 in montreal to address concerns of ozone depletion by cfcs. How the ozone layer forms and protects formation of the. Jun, 2017 the hole in the ozone layer above antarctica has more farreaching consequences than previously assumed. As a pollutant it should not be confused with the separate problem of stratospheric ozone depletion. That article is easy enough to understand, and better written than this one. Causes of ozone layer depletion and its effects on human. This is anomalously large in comparison to recent years. Technically, the term ozone hole should be applied to regions where stratospheric ozone depletion is so severe that levels fall below 200 dobson units d. 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.
Measurements from satellitebased instruments show that this area of very low ozone concentration has developed over antarctica every year since about 1975. Didnt we deal with that pesky hole in the ozone layer more than two decades ago. Ozone hole cause and effects chlorofluorocarbon ozone. Pdf causes of ozone layer depletion and its effects on. Scientists say the antarctic ozone hole is on the road to recovery. After some study, atmospheric scientists recognized that this ozone depletion was a result of air pollutants from human activities specifically, the release of nontoxic, aerosol gas molecules called chlorofluorocarbons. Jan, 2016 the ozone hole was super scary, so what happened to it. The ozone layer covers the earth and acts as a shield against ultraviolet radiation from the sun.
Ozone hole healing could cause further climate warming. Scientific assessment of ozone depletion 1998 faq 5. The state of scientific understanding regarding the ozonedepletion issue has advanced in recent years as a result of the concerted efforts of hundreds of scientists worldwide. The data were acquired by the ozone monitoring instrument on nasas aura satellite. Furthermore, the hole is not as deep as it used to be. Nov 11, 2016 to mark the peak of ozone hole season, were highlighting four ways that climate and the ozone hole are relatedand one important way they arent. Apart from acting as a greenhouse gas ozone also acts as a strong oxidant that has a proven harmful effect on crops, the growth of forests and human health. Jan 09, 2018 the good news about the ozone hole is even better than you think. Ozone depletion consists of two related events observed since the late 1970s. Therefore many governments are taking measures to prevent ozone depletion. Satellite instruments monitor the ozone layer, and we use their data to create the images that depict the amount of ozone. The ozone hole has steadily grown in size and length of existence over the past two and half decades. Proper usage and audio pronunciation plus ipa phonetic transcription of the word ozone hole. With the increased atmospheric chlorine levels present since the 1980s, the antarctic ozone.
Its over 25 years since the discovery of the ozone hole drew world attention to the impact of human activity on the global environment. The lowest concentration of the hole was about 30% of the normal level. The ozone problem is back and worse than ever science. The ozone hole is an area where the amount of ozone in the upper atmosphere is much lower than normal.
The hole in the ozone layer is now steadily closing, but its repair could. National aeronautics and the ozone hole space administratio n. Study 50 terms chapter 2 chem 100 flashcards quizlet. The main things that lead to destruction of the ozone gas in the ozone layer. The antarctic ozone hole is an area of the antarctic stratosphere in which the recent ozone levels have dropped to as low as 33 percent of their pre1975 values.
The origin of the ozone hole natural or anthropological james a. The good news about the ozone hole is even better than you think. The antarctic ozone hole is a region of extreme ozone loss. Nasa climate change and atmospheric circulation will. Ozone layer depletion causes, effects and solutions 7. The ozone layer becomes thinner, and this is called the ozone hole. March 7, 2017 in 1985 scientists who were a part of the british antarctic survey published results showing that there was a hole in the ozone layer above the antarctic shocking the scientific community as the decline was far higher than anticipated. 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. Progress report 2003 united nations environment programme, environmental e. Half their normal amount and open pdf in new window firefox the ozone hole covers the entire continent. Given that these risks exist even when the ozone layer absorbs about 98 percent of uv light, a future with an even thinner ozone layer is scary indeed. 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. The appearance of a hole in the earths ozone layer over antarctica, first detected in 1976, was. August 25, 2009 latest information on the current antarctic ozone hole as monitored by gome2.
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