Nevertheless, after the war they slowly became more common in civil aviation as well. Use of CFCs In the past, CFCs have been widely used as coolants in refrigeration and air conditioners, as solvents in cleaners, particularly for electronic circuit boards, as a blowing agents in the production of foam e.
Neither group, however, had realized that CFCs were a potentially large source of stratospheric chlorine—instead, they had been investigating the possible effects of HCl emissions from the Space Shuttlewhich are very much smaller.
Polar winters are dark, consisting of three months without solar radiation sunlight. Bromomethane is widely used as a fumigant. In such conditions the ice crystals of the cloud provide a suitable surface for conversion of unreactive chlorine compounds into reactive chlorine compounds, which can deplete ozone easily.
The first Chlorofluorocarbon was CFC, a single carbon with two chlorines and two Fluorines attached to it. This is normally expressed in Dobson units ; abbreviated as "DU". These elements are found in stable organic compounds, especially chlorofluorocarbonswhich can travel to the stratosphere without being destroyed in the troposphere due to their low reactivity.
Moreover, the polar vortex formed over Antarctica is very tight and the reaction occurring on the surface of the cloud crystals is far different from when it occurs in atmosphere.
The alternative technologies already adopted have been effective and inexpensive enough that consumers have not yet felt any noticeable impacts except for an increase in automobile air conditioning service costs " UNEP, The loss of stratospheric ozone could also significantly cool the stratosphere, potentially causing destructive climate change.
Antarctic total column ozone in September and October have continued to be 40—50 percent lower than pre-ozone-hole values since the s. National Academy of Sciences as justification that since the science was so uncertain, action should not be taken.
However, the economic reality has been less dire. Myth and Realities", th Congress, 1st session, September 20,Report no. During the hearings, Representative John Doolittle, a California Republican, stated, "My own belief, is that the question is still very much open to debate The net reaction in both cases is two ozone molecules forming three oxygen molecules.
I found extremely misleading representations by the government and government officials that are not founded on sound science.
Antarctic ozone hole[ edit ] The discovery of the Antarctic "ozone hole" by British Antarctic Survey scientists FarmanGardiner and Shanklin first reported in a paper in Nature in May  came as a shock to the scientific community, because the observed decline in polar ozone was far larger than anyone had anticipated.
This is partly because UVAwhich has also been implicated in some forms of skin cancer, is not absorbed by ozone, and because it is nearly impossible to control statistics for lifestyle changes over time. The list should include name of ODS, type and location of equipment, quantity in kg and date.
ODSs are halogen source gases controlled under the Montreal Protocol. The reactive gases formed from halogen source gases react chemically to destroy ozone in the stratosphere. Early models failed to take PSCs into account and predicted a gradual global depletion, which is why the sudden Antarctic ozone hole was such a surprise to many scientists.
The ClO can react with a second molecule of ozone, releasing the chlorine atom and yielding two molecules of oxygen.Byin response to a dramatic seasonal depletion of the ozone layer over Antarctica, diplomats in Montreal forged a treaty, the Montreal Protocol, which called for drastic reductions in.
10 days ago · Researchers have managed to make a breakthrough when it comes to dealing with the extremely ozone-depleting chlorofluorocarbon Freon Their findings could make a major contribution to. The Ozone Hole: Navigate.
Chlorofluorcarbons. Introduction. Man-made CFCs are the main cause of stratospheric ozone depletion. CFCs have a lifetime of about 20 to years, and consequently one free chlorine atom from a CFC molecule can do a lot of damage, destroying ozone molecules for a long time.
Although emissions of CFCs around the. The stratospheric ozone layer is Earth’s “sunscreen” – protecting living things from too much ultraviolet radiation. The emission of ozone depleting substances has been damaging the ozone layer.
Sep 11, · View the latest status of the ozone layer over the Antarctic, with a focus on the ozone hole. Satellite instruments monitor the ozone layer, and we use their data to create the images that depict the amount of ozone.
The Ozone Hole.
For nearly a billion years, ozone molecules in the atmosphere have protected life on Earth from the effects of ultraviolet rays.Download