1. Ozone Layer - Wikipedia, The Free Encyclopedia The ozone layer is a layer in Earth's atmosphere which contains relatively high concentrations of ozone (O 3). This layer absorbs 97–99% of the Sun 's high frequency ultraviolet http://en.wikipedia.org/wiki/Ozone_layer

Ozone layer From Wikipedia, the free encyclopedia Jump to: navigation search The ozone layer is a layer in Earth's atmosphere which contains relatively high concentrations of ozone (O ). This layer absorbs 97–99% of the Sun 's high frequency ultraviolet light , which is potentially damaging to life on Earth. It is mainly located in the lower portion of the stratosphere The ozone layer was discovered in 1913 by the French physicists Charles Fabry and Henri Buisson . Its properties were explored in detail by the British meteorologist G. M. B. Dobson , who developed a simple spectrophotometer (the Dobsonmeter ) that could be used to measure stratospheric ozone from the ground. Between 1928 and 1958 Dobson established a worldwide network of ozone monitoring stations which continues to operate today. The " Dobson unit ", a convenient measure of the columnar density of ozone overhead, is named in his honour. Contents Origin of ozone Ultraviolet light and ozone Distribution of ozone in the stratosphere Ozone depletion ... edit Origin of ozone Ozone-oxygen cycle in the ozone layer.

2. Ozone_layer | Define Ozone_layer At Dictionary.com –noun Meteorology . the layer of the upper atmosphere where most atmospheric ozone is concentrated, from about 8 to 30 mi. (12 to 48 km) above the earth, with the maximum http://dictionary.reference.com/browse/Ozone_layer

3. The RSPB: Teaching: The Ozone Layer Answers several frequently asked questions about the ozone layer. http://www.rspb.org.uk/ourwork/teaching/resources/science/ozone_layer.asp

E-mail to a friend E-newsletter Contact us Home ... Science The ozone layer Children often get the greenhouse effect and ozone depletion muddled. The two are not actually linked. Here is what is known about the causes and results of ozone depletion. What is the hole in the ozone layer? In 1984, it was found that the amount of ozone in the atmosphere above Antarctica was much less than expected. Since then, ozone 'holes' have been found over other parts of the world, including Europe. This general loss of ozone in the stratosphere, which is found 15 - 50km above the Earth's surface, is called ozone depletion and is not concentrated in 'holes'. Why does it matter? The ozone layer absorbs most of the ultraviolet light coming from the sun. This far ultraviolet light, called UV-B, is harmful to plants and animals. It causes cancers and eye damage in animals, and reduces the growth rate of some plants, including the microscopic plants called plankton living in the oceans, which are an important source of food for animals. How is it caused?

4. What Is Depletion Of The Ozone Layer? | Questions Kids Ask About The Earth - Lea Tells how ozone is broken apart by the Sun s powerful rays, and by human-made chemicals. http://www.faqkids.com/idx/4/010/The_Earth/article/What_is_Depletion_of_the_Ozon

Answers to Questions Kids Ask! - Where "Why?" Turns to "Wow!" Get a Random Question Animals Art Food ... Get a Random Question Word of the Day galore: galore: in abundance; in plentiful amounts. Born on this day August 25, 2010 - Ivan The Terrible - Leonard Bernstein - Mel Ferrer - Sir Sean Connery - Frederick Forsyth - Howard Jacobson - Ann Archer - Martin Amis - Elvis Costello - Matt Aitken - Billy Ray Cyrus - Claudia Schiffer You are here: Questions The Earth What is Depletion of the Ozone layer? Q: What is Depletion of the Ozone layer? A: Some UV-B light reaches us, and it is actually helpful in converting cholesterol to vitamin D in our skin. (So a reasonable amount of sunlight is good for your body!) But it also causes suntans and sunburns. The effects of ozone depletion extend beyond cancer and killing crops. It also may cause a greenhouse effect, gradually warming the earth to the point where our polar ice caps melt and flood the coastal cities. This is a very long-term effect, though. UV-B rays also seem to have a harmful effect on amphibian eggs, which may be one cause for the recent and drastic drop in frog populations. There are likely to be many other effects of ozone depletion which we will discover in years to come. In: The Earth Answer provided by Dr. Universe

5. Ozone Layer - New World Encyclopedia The ozone layer is a layer in Earth's atmosphere that contains relatively high concentrations of ozone (O 3). It is mainly located in the lower portion of the stratosphere, from http://www.newworldencyclopedia.org/entry/Ozone_layer

Ozone layer From New World Encyclopedia Jump to: navigation search Previous (Ozone) Next (P.G.T. Beauregard) The ozone layer is a layer in Earth's atmosphere that contains relatively high concentrations of ozone (O ). It is mainly located in the lower portion of the stratosphere, from approximately ten kilometers (km) to 50 km above Earth's surface, though the thickness varies seasonally and geographically. The actual ozone concentration in this layer is only about a few parts per million, which is small compared to the main components of the atmosphere, but it is much higher than the concentrations of ozone in the lower atmosphere. The ozone in this layer absorbs most of the Sun 's high-frequency ultraviolet (UV) light, which is potentially damaging to life on earth. It thus serves a protective function. Recently, however, there has been concern that the ozone layer is being depleted by reactions with free radicals derived from certain manmade chemicals (such as chlorofluorocarbons (CFCs)) released into the atmosphere. Use of these chemicals is now strictly regulated or prohibited in a number of countries, and the ozone depletion rate appears to have slowed down. Contents Discovery Origin of ozone Ultraviolet light and ozone DNA sensitivity to UV ... Credits Discovery The ozone layer was discovered in 1913 by the French physicists Charles Fabry and Henri Buisson. Its properties were explored in detail by the British meteorologist G. M. B. Dobson, who developed a simple spectrophotometer (the Dobsonmeter) that could be used to measure stratospheric ozone from the ground. Between 1928 and 1958, Dobson established a worldwide network of ozone monitoring stations that continues to operate as of 2008. The "Dobson unit," a convenient measure of the total amount of ozone in a column overhead, is named in his honor.

6. Ozone Layer Generous sponsorship of Windows to the Universe is provided by the Hewlett Foundation, the American Geological Institute, the American Geophysical Union, the National Science http://www.windows2universe.org/earth/Atmosphere/ozone_layer.html

7. Ozone Layer - Simple English Wikipedia, The Free Encyclopedia The ozone layer is a layer of ozone high up in the Earth 's atmosphere (stratosphere). In the region between about 10 kilometres and about 50 kilometres above ground, the http://simple.wikipedia.org/wiki/Ozone_layer

Ozone layer From Wikipedia, the free encyclopedia Jump to: navigation search A weather balloon is sent up from the South Pole to measure the ozone layer NASA photo showing the hole in the ozone layer over Antarctica The ozone layer is a layer of ozone high up in the Earth 's atmosphere ( stratosphere ). In the region between about 10 kilometres and about 50 kilometres above ground, the atmosphere contains more ozone (O ). The exact amount of ozone that can be found varies, the seasons influence it; it is also different in different places on the earth. This layer can absorb between 93 and 99 percent of the ultraviolet radiation from the sun This radiation is dangerous to many living organisms on earth. Over the last hundred years the ozone layer has been damaged by man-made chemicals , especially ones called CFCs ( chlorofluorocarbons ). CFCs were used in spray cans , but also as solvents or as cooling agents in refrigerators . They have been replaced by other substances for most applications. There is now a hole in the layer over Antarctica . This means that there will be more ozone in the atmosphere, and that

8. Ozone Layer The ozone layer is the part of the Earth's atmosphere which contains relatively high concentrations of ozone (O3). Relatively high means a few parts per million much higher http://www.sciencedaily.com/articles/o/ozone_layer.htm

Science Reference Share Blog Print Email Bookmark Ozone layer The ozone layer is the part of the Earth's atmosphere which contains relatively high concentrations of ozone (O3). See also: Zoology Ozone Holes Atmosphere Environmental Issues "Relatively high" means a few parts per million - much higher than the concentrations in the lower atmosphere but still small compared to the main components of the atmosphere. Although the concentration of ozone in the ozone layer is very small, it is vitally important to life because it absorbs biologically harmful ultraviolet (UV) radiation from the Sun. The "thickness" of the ozone layer - that is, the total amount of ozone in a column overhead - varies by a large factor worldwide, being in general smaller near the equator and larger as one moves towards the poles. It also varies with season, being in general thicker during the spring and thinner during the autumn. For more information about the topic Ozone layer , read the full article at Wikipedia.org , or see the following related articles: Tropospheric ozone read more Atmospheric chemistry read more ... read more Note: This page refers to an article that is licensed under the GNU Free Documentation License . It uses material from the article Ozone layer at Wikipedia.org. See the

9. Ozone Layer: Facts, Discussion Forum, And Encyclopedia Article The atmosphere of Earth is a layer of gases surrounding the planet Earth that is retained by Earth's gravity. The atmosphere protects life on Earth by absorbing ultraviolet http://www.absoluteastronomy.com/topics/Ozone_layer

Home Discussion Topics Dictionary ... Login Ozone layer Ozone layer Topic Home Discussion Definition Overview The ozone layer is a layer in Earth's atmosphere Earth's atmosphere The atmosphere of Earth is a layer of gases surrounding the planet Earth that is retained by Earth's gravity. The atmosphere protects life on Earth by absorbing ultraviolet solar radiation, warming the surface through heat retention , and reducing temperature extremes between day and night... which contains relatively high concentrations of ozone Ozone Ozone , or Trioxygen, is a triatomic molecule, consisting of three oxygen atoms. It is an allotrope of oxygen that is much less stable than the diatomic allotrope... (O ). This layer absorbs 97–99% of the sun Sun The Sun is the star at the center of the Solar System. It has a diameter of about , about 109 times that of Earth, and its mass accounts for about 99.86% of the total mass of the Solar System.... 's high frequency ultraviolet light, which is potentially damaging to life on earth. Over 90% of the ozone in Earth's atmosphere is present here. It is mainly located in the lower portion of the stratosphere Stratosphere The stratosphere is the second major layer of Earth's atmosphere, just above the troposphere, and below the mesosphere. It is stratified in temperature, with warmer layers higher up and cooler layers farther down...

10. What Is The Ozone Layer? What is the ozone layer? The ozone layer is a deep layer in the stratosphere, encircling the Earth, that has large amounts of ozone in it. The layer shields the entire Earth http://www.weatherquestions.com/What_is_the_ozone_layer.htm

HOME CLOUD/PRECIP FCST MOVIE TEMPERATURE FCST MOVIE 2007 HURRICANES ... 2008 HURRICANES What is the ozone layer? The ozone layer is a deep layer in the stratosphere , encircling the Earth, that has large amounts of ozone in it. The layer shields the entire Earth from much of the harmful ultraviolet radiation that comes from the sun. Interestingly, it is also this ultraviolet radiation that forms the ozone in the first place. Ozone is a special form of oxygen, made up of three oxygen atoms rather than the usual two oxygen atoms. It usually forms when some type of radiation or electrical discharge separates the two atoms in an oxygen molecule (O ), which can then individually recombine with other oxygen molecules to form ozone (O ). The ozone layer became more widely appreciated when it was realized that certain chemicals mankind manufactures, called chloroflurocarbons, find their way up into the stratosphere where, through a complex series of chemical reactions, they destroy some of the ozone. As a result of this discovery, an international treaty was signed, the the manufacture of these chemicals was stopped. The ozone layer has since begun to recover as a result of these efforts. This stratospheric ozone, which protects us from the sun, is good. There is also ozone produced near the ground, from sunlight interacting with atmospheric pollution in cities, that is bad. It causes breathing problems for some people, and usually occurs in the summertime when the pollution over a city builds up during stagnant air conditions associated with high pressure areas.

11. Ozone Layer Ozone Layer. The ozone layer is a layer of ozone particles scattered between 19 and 30 kilometres (12 to 30 miles) up in the Earth's atmosphere, in a region called the http://www.ace.mmu.ac.uk/eae/Atmosphere/Older/Ozone_Layer.html

Ozone Layer The ozone layer is a layer of ozone particles scattered between 19 and 30 kilometres (12 to 30 miles) up in the Earth's atmosphere, in a region called the stratosphere . The concentration of ozone in the ozone layer is usually under 10 parts ozone per million. Without the ozone layer, ultraviolet (UV) radiation from the Sun would not be stopped from entering the Earth's atmosphere and arriving at the surface, causing damage to most living species. Ozone is created in the stratosphere when highly energetic solar radiation strikes molecules of oxygen (O ) and causes the two oxygen atoms to split apart. If a freed atom bumps into another O , it joins up, forming ozone (O ). This process known as photolysis. Ozone is also naturally broken down in the stratosphere by sunlight and by a chemical reaction with various compounds containing nitrogen , hydrogen and chlorine. These chemicals all occur naturally in the atmosphere in very small amounts. In an unpolluted atmosphere there is a balance between the amount of ozone being produced and the amount of ozone being destroyed. As a result, the total amount of ozone in the stratosphere remains relatively constant. The amount of ozone within the stratosphere varies according to altitude. Ozone concentrations are highest between 19 and 23 km, but there are significant amounts up to 30 km. At these levels in the atmosphere however, the

12. Ozone Layer Ozone Layer. The ozone layer is not really a layer at all, but has become known as such because most ozone particles are scattered between 19 and 30 kilometres (12 to 30 miles) up in http://www.ace.mmu.ac.uk/eae/Ozone_Depletion/Older/Ozone_Layer.html

Ozone Layer The ozone layer is not really a layer at all, but has become known as such because most ozone particles are scattered between 19 and 30 kilometres (12 to 30 miles) up in the Earth's atmosphere, in a region called the stratosphere . The concentration of ozone in the ozone layer is usually under 10 parts ozone per million. Without the ozone layer, a lot of ultraviolet (UV) radiation from the Sun would not be stopped reaching the Earth's surface, causing untold damage to most living species. In the 1970s, scientists discovered that chlorofluorocarbons (CFCs) could destroy ozone in the stratosphere. Ozone is created in the stratosphere when UV radiation from the Sun strikes molecules of oxygen (O ) and causes the two oxygen atoms to split apart. If a freed atom bumps into another O , it joins up, forming ozone (O ). This process is known as photolysis. Ozone is also naturally broken down in the stratosphere by sunlight and by a chemical reaction with various compounds containing nitrogen, hydrogen and chlorine. These chemicals all occur naturally in the atmosphere in very small amounts. In an unpolluted atmosphere there is a balance between the amount of ozone being produced and the amount of ozone being destroyed. As a result, the total concentration of ozone in the

13. Database Error - Free Net Encyclopedia The ozone layer, or ozonosphere layer (rarely used term), is that part of the Earth 's atmosphere which contains relatively high concentrations of ozone (O 3). http://www.netipedia.com/index.php/Ozone_layer

class="ns-0"> Database error From Free net encyclopedia A database query syntax error has occurred. This may indicate a bug in the software. The last attempted database query was: (SQL query hidden) from within function " MediaWikiBagOStuff:_doquery ". MySQL returned error " Retrieved from " http://www.netipedia.com/index.php/Ozone_layer Views Article Discussion Edit History Personal tools Create an account or log in Search Partner sites Social Network for Translators and Translation Agencies User-Friendly Translation Memory Software Professional Translation Tools for Freelance Translators and Translation Agencies Project Management Software for Translation Agencies ... About Free net encyclopedia

14. Ozone Layer The ozone layer is a layer in Earth's atmosphere which contains relatively high concentrations of ozone (O3). This layer absorbs 97–99% of the sun's high frequency http://www.kosmix.com/topic/Ozone_layer

Kosmix One sec... we're building your guide for Ozone Layer document.k_start_apptier = "Nov 01 20:19:20.95053"; kapp.assignCol($('ads_banner_top'), 'topnav_container'); Ozone layer Overview Shopping Images Video ... Reference kapp.nav_menu_container = $('refine_nav').down(".navs_container"); kapp.assignCol($('refine_nav'), 'topnav_container'); kapp.assignCol($('uc_kosmixarticles_shadow'), 'right_container'); Articles for Ozone layer The Kosmix Community Author: Barbara Rossi Contact: Facebook The ozone layer is one of the layers of the Earth's atmosphere. It is responsible for blocking over 95% of ultraviolet light, which can be damaging to life on our planet. The thickness of the ozone layer varies by region and by season, usually thicker by the poles and thinner above the equator. In recent years, the phenomenon of ozone depletion has caused much worry around the world. This alarming phenomenon is caused by the increased release of free radical-causing substances into the atmosphere. Man-made compounds such as ... see more The ozone layer is one of the layers of the Earth's atmosphere. It is responsible for blocking over 95% of ultraviolet light, which can be damaging to life on our planet. The thickness of the ozone layer varies by region and by season, usually thicker by the poles and thinner above the equator. In recent years, the phenomenon of ozone depletion has caused much worry around the world. This alarming phenomenon is caused by the increased release of free radical-causing substances into the atmosphere. Man-made compounds such as bromoflourcarbons have the same properties as other ozone-depleting substances already present in nature, but their release in large quantities has significantly worsened the situation. Bans have been put in place recently to put a stop to the use of these dangerous chemicals in everyday products in order to try and reverse this trend.

15. Ozone Layer | Ask.com Encyclopedia The ozone layer is a layer in Earth's atmosphere which contains relatively high concentrations of ozone (O 3). This layer absorbs 97–99% of the sun 's high frequency ultraviolet http://www.ask.com/wiki/Ozone_layer?qsrc=3044

16. Ozone Layer | SunWise For Kids | US EPA Ozone Layer . The ozone layer forms a thin shield high up in the sky. It protects life on Earth from the sun's ultraviolet (UV) rays. In the 1980s, scientists began finding clues http://www.epa.gov/sunwise/kids/kids_ozone.html

SunWise Kids SunWise Home Kids Home Skip topic navigation links Survivor Challenges Ozone Layer UV Index SunWise Action Steps Ozone Layer The ozone layer forms a thin shield high up in the sky. It protects life on Earth from the sun's ultraviolet (UV) rays. In the 1980s, scientists began finding clues that the ozone layer was going away or being depleted. This allows more UV radiation to reach the Earth's surface. This can cause people to have a greater chance of getting too much UV radiation. Too much UV can cause bad health effects like skin cancer and eye damage. What Is Stratospheric Ozone? Ozone is a natural gas that is found in two different layers of the atmosphere. One layer, called the troposphere , is at the Earth's surface where we live. Ozone in the troposphere is "bad" because it dirties the air and helps make smog, which is unhealthful to breathe. The other layer, called the stratosphere , is miles above the Earth's surface. Ozone in the stratosphere is "good" because it protects life on Earth by absorbing some of the sun's harmful UV rays. Stratospheric ozone is found most often between six and 30 miles above the Earth's surface. Ozone Depletion Recently, chlorofluorocarbons (CFCs) were used a lot in industry and elsewhere to keep things cold and to make foam and soaps. Strong winds carry CFCs up into the stratosphere where UV radiation breaks them apart, releasing chlorine atoms. Each chlorine atom can attack and break apart (destroy) as many as 100,000 ozone molecules during the time it is in the stratosphere. The chlorine from CFCs reduces (depletes) the amount of ozone in the stratosphere.

17. Ozone Depletion - Wikipedia, The Free Encyclopedia Since the ozone layer absorbs UVB ultraviolet light from the Sun, ozone layer depletion is expected to increase surface UVB levels, which could lead to damage, including increases http://en.wikipedia.org/wiki/Ozone_depletion

Ozone depletion From Wikipedia, the free encyclopedia Jump to: navigation search Image of the largest Antarctic ozone hole ever recorded (September 2006). Ozone depletion describes two distinct, but related observations: a slow, steady decline of about 4 percent per decade in the total volume of ozone in Earth 's stratosphere (the ozone layer ) since the late , and a much larger, but seasonal, decrease in stratospheric ozone over Earth's polar regions during the same period. The latter phenomenon is commonly referred to as the ozone hole . In addition to this well-known stratospheric ozone depletion, there are also tropospheric ozone depletion events , which occur near the surface in polar regions during spring. The detailed mechanism by which the polar ozone holes form is different from that for the mid-latitude thinning, but the most important process in both trends is catalytic destruction of ozone by atomic chlorine and bromine. The main source of these halogen atoms in the stratosphere is photodissociation of chlorofluorocarbon (CFC) compounds, commonly called

18. CFCs And Ozone Depletion This process was known to be potentially damaging to the ozone layer, but conclusive evidence of stratospheric ozone loss was not discovered until 1984. http://www.ciesin.org/TG/OZ/cfcozn.html

CIESIN Thematic Guides Chlorofluorocarbons and Ozone Depletion Chlorofluorocarbons (CFCs), along with other chlorine- and bromine-containing compounds, have been implicated in the accelerated depletion of ozone in the Earth's stratosphere. CFCs were developed in the early 1930s and are used in a variety of industrial, commercial, and household applications. These substances are non-toxic, non-flammable, and non-reactive with other chemical compounds. These desirable safety characteristics, along with their stable thermodynamic properties, make them ideal for many applicationsas coolants for commercial and home refrigeration units, aerosol propellants, electronic cleaning solvents, and blowing agents. Production and Use of Chlorofluorocarbons experienced nearly uninterrupted growth as demand for products requiring their use continued to rise. Not until 1973 was chlorine found to be a catalytic agent in ozone destruction. Catalytic destruction of ozone removes the odd oxygen species [atomic oxygen (O) and ozone (O3)] while leaving chlorine unaffected. This process was known to be potentially damaging to the ozone layer, but conclusive evidence of stratospheric ozone loss was not discovered until 1984. Announcement of polar ozone depletion over Antarctica in March 1985 prompted scientific initiatives to discover the Ozone Depletion Processes , along with calls to freeze or diminish production of chlorinated fluorocarbons. A complex scenario of atmospheric dynamics, solar radiation, and chemical reactions was found to explain the anomalously low levels of ozone during the polar springtime. Recent expeditions to the Arctic regions show that similar processes can occur in the northern hemisphere, but to a somewhat lesser degree due to warmer temperatures and erratic dynamic patterns.

19. Ozone Hole FAQ : Weather Underground Smith, D.A., K. Vodden, L. Rucker, and R. Cunningham, Global Benefits and Costs of the Montreal Protocol on Substances that Deplete the Ozone Layer , Applied Research Consultants http://www.wunderground.com/education/holefaq.asp

Favorites You don't appear to have any favorites yet, or your cookies may be disabled. Edit My Favorites WunderPhotos Photos! Browse All Photos WunderMap View WunderMap Website Spotlight Weather Maps Solar Calculator Forecast Flyer Community Chat ... WU News Blog Welcome to Weather Underground! Sign In or Create an Account . Edit my Page Preferences Full Screen Mobile iPhone ... Download Search: Weather Conditions Personal Weather Stations WunderPhotos Blogs Local Weather My Locations History Data Weather Stations ... Climate Change Frequently Asked Questions About The Ozone Hole By Jeffrey Masters, Ph.D. What is the Ozone Hole? How big was the 2003 Ozone Hole, and is it getting bigger? Has there been ozone loss in places besides Antarctica? ... Where can I go to learn more about the ozone hole? What is the ozone hole? The "ozone hole" is a loss of stratospheric ozone in springtime over Antarctica, peaking in September. The ozone hole area is defined as the size of the region with total ozone below 220 Dobson units (DU). Dobson Units are a unit of measurement that refer to the thickness of the ozone layer in a vertical column from the surface to the top of the atmosphere, a quantity called the "total column ozone amount." Prior to 1979, total column ozone values over Antarctica never fell below 220 DU. The hole has been proven to be a result of human activitiesthe release of huge quantities of chlorofluorocarbons (CFCs) and other ozone depleting substances into the atmosphere. How big was the 2003 ozone hole, and is it getting bigger?

20. Ozone Layer The Ozone Layer The ozone layer refers to the ozone within stratosphere, where over 90% of the earth's ozone resides. http://www.nas.nasa.gov/About/Education/Ozone/ozonelayer.html

The Ozone Layer "The ozone layer" refers to the ozone within stratosphere, where over 90% of the earth's ozone resides. Ozone is an irritating, corrosive, colorless gas with a smell something like burning electrical wiring. In fact, ozone is easily produced by any high-voltage electrical arc (spark plugs, Van de Graaff generators, Tesla coils, arc welders). Each molecule of ozone has three oxygen atoms and is produced when oxygen molecules (O2) are broken up by energetic electrons or high energy radiation. For information on the history of the ozone layer for the layman, see the Short history of ozone depletion , National Oceanic and Atmospheric Administration's NOAA Ozone overview or NOAA on stratospheric ozone . For short and to-the-point answers, check out Robert Parson's Ozone overview, FAQ1 The Stratosphere Variations in temperature and pressure divide the earths atmosphere into layers, shown below, and

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