CFCs escaping from airconditioners and refrigerators in the nothern hemisphere sneaking down to the antarctic where these rather heavy molecules were magically lifted up against gravity to go up into the stratosphere where they were disassociated into chlorine atoms while ocean spray chlorine ions were washed out of the atmosphere by rain just like the chlorine atoms injected into the stratosphere by an active volcano down there. Surely, if we calculate the volume of ozone in the collar we could see if it can be distributed over the hole demonstrating how much, if any, ozone has been actually lost
The Environmental Protection Agency projects more than 60 million additional cases of skin cancer, 17 million additional cases of cataracts, and about 1 million additional deaths among Americans born by the year 2075 if CFC usage continues at its present rate. Scientists predict that, beyond the health risks to humans, a prolonged increase of UV-B rays could set in motion far-reaching and unpredictable ecological changes
What is Damaging the Ozone Layer
However, it was still used in some other products and industrial processes and CFC production in the UK did not finally come to an end until 2000.Scientists now expect that bromine levels will peak before 2010 and then begin to drop but since a high proportion come from uncontrolled or natural sources, such as the sea, it will take many years for levels to drop significantly. Ozone Depleting Substances CFCs, which contain carbon, chloride and fluorine are now known to damage the Ozone Layer but there are a number of other industrial processes and man-made chemicals which also cause damage
WebLessons: Fixing the Ozone Hole
What is the relationship between the temperature in the Antarctic and the size of the ozone hole? Answer: When the temperatures drop to their lowest levels, more ozone is destroyed, so the hole gets larger. Why was the ozone layer getting thin? What caused the hole? How big is it today? What are people doing to stop it? You will explore this scientific puzzle in this lesson, and you will find out how you can help protect the ozone
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 facilitate the chemical reactions involved. When the Antarctic spring sun rises in August or September and hits the trapped chemicals, a chain reaction begins in which chlorine, bromine (from the halons), and ice crystals react with the ozone and destroy it very quickly
Ozone Depletion Information, Ozone Depletion Facts, Ozone Layer, Ozone Hole - National Geographic
This is what some people erroneously refer to as the "ozone hole." In other regions, the ozone layer has deteriorated by about 20 percent.About 90 percent of CFCs currently in the atmosphere were emitted by industrialized countries in the Northern Hemisphere, including the United States and Europe
How does the ozone layer protect Earth from radiation?
The southern hemisphere has been affected more by ozone depletion than the northern hemisphere due to several geophysical and atmospheric factors which have lead to the annual appearance of the ozone hole over Antarctica. For consecutive clear sky days, large but natural changes in ozone levels in the stratosphere above cities can affect the solar UVR at the surface significantly
These CFCs had made their way into the upper atmosphere where the much stronger UV radiation from the Sun had broken them down into their component molecules, releasing the potentially damaging chlorine (and bromine) atoms, which, given the right conditions, could destroy ozone. Inline movie of TOMS ozone measurements from Nov 1978 to Jan 1992(3.7 Mb) MPEG movie of TOMS ozone measurements from Nov 1978 to Jan 1992(1 Mb) The TOMS instrument measures ozone levels from the back-scattered sunlight, specifically in the ultra-violet range
If you took all the ozone in a vertical column above the instrument and brought it down to sea level it would form a layer just three millimetres thick. This discovery changed the world.What happened after the hole was discovered?NASA scientists used their satellite data to confirm that not only was the hole over British research stations but it covered the entire Antarctic continent
Saving the ozone was literally the first thing the whole world ever agreed on: A treaty banning CFCs was the first agreement ever to be ratified by every country in the United Nations
The value of 220 Dobson Units is chosen since total ozone values of less than 220 Dobson Units were not found in the historic observations over Antarctica prior to 1979. What is the ozone hole? Each year for the past few decades during the Southern Hemisphere spring, chemical reactions involving chlorine and bromine cause ozone in the southern polar region to be destroyed rapidly and severely
In 1992, reacting to the latest scientific assessment of the ozone layer, the Parties to the Protocol decided to completely end production of halons by the beginning of 1994 and of CFCs by the beginning of 1996 in developed countries. UVB has been linked to many harmful effects, including various types of skin cancer, cataracts, and harm to some crops, certain materials, and some forms of marine life
Good news: The hole in the ozone layer is finally starting to heal - Vox
Under the Montreal Protocol of 1987, the world's nations agreed to phase out the use of CFCs in refrigerators, spray cans, insulation foam and fire suppression. Unexpected side effects of the Montreal Protocol Giant tabular icebergs are surrounded by ice floe drift in Vincennes Bay on January 11, 2008 in the Australian Antarctic Territory
After making revisions, the author submits the article back to the journal editor, who can then accept the article, reject it, or send it back for another round of review. They also asked how Americans would go about putting sunscreen and hats on cows and stalks of corn, since plants and animals are adversely affected by UV light, as well
The Ozone Hole-Ozone Hole History
The 100 hPa temperature over Halley and Vernadsky was below the long term mean for most of the season.Total ozone values fell from an estimated 300 DU in early July to around 200 DU in mid August. These Polar Stratospheric Clouds (PSC's) are composed of ice crystals that provide the surface for a multitude of reactions, many of which speed the degradation of ozone molecules
Another story goes that the TOMS satellite data didn't show the dramatic loss of ozone because the software processing the raw ozone data from the satellite was programmed to treat very low values of ozone as bad readings! Later analysis of the raw data when the results from the British Antarctic Survey team were published, confirmed their results and showed that the loss was rapid and large-scale; over most of the Antarctica continent. CFC's are a common industrial product, used in refrigeration systems, air conditioners, aerosols, solvents and in the production of some types of packaging
Then I did a really careful calibration and found a pattern: every spring a major hole appeared in the ozone layer over the Antarctic, one that was getting bigger and bigger each year. Within a few years of the discovery it was agreed to set up the Montreal Protocol, which banned the manmade chemicals responsible for depleting ozone in the upper atmosphere
The Ozone Hole
Scientific theory and evidence suggest that, once emitted to the atmosphere, these compounds could significantly deplete the stratospheric ozone layer that shields the planet from damaging UV-B radiation. The Ozone Hole About Us Awards Donate Contact Us Site Map News Links Ozone Hole History Montreal Protocol Ozone Hole 2006 Ozone hole 2014 Arctic Ozone Hole The Ozone Hole For nearly a billion years, ozone molecules in the atmosphere have protected life on Earth from the effects of ultraviolet rays
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