In the image below, the upper ranges of possible effects from the ozone changes are indicated by the open bars, and the lower ranges are indicated by the solid bars. As shown in the figure, the increase in carbon dioxide is the major contributor to climate change.
Carbon dioxide concentrations are increasing in the atmosphere primarily as the result of the burning of coal, oil, and natural gas for energy and transportation. The relative impacts on climate of various other "greenhouse" gases are also shown on the figure. There is an additional factor that indirectly links ozone depletion to climate change; namely, many of the same gases that are causing ozone depletion are also contributing to climate change.
These gases, such as the chlorofluorocarbons CFCs , are greenhouse gases, absorbing some of the infrared radiation emitted by the Earth's surface, thereby effectively heating the Earth's surface. And at the end of , the United Nations confirmed in a scientific assessment that the ozone layer is recovering, projecting that it would heal completely in the non-polar Northern Hemisphere by the s, followed by the Southern Hemisphere in the s and polar regions by A study in early found that ozone in the lower stratosphere unexpectedly and inexplicably has dropped since , while another pointed to possible ongoing violations of the Montreal pact.
The world is not yet in the clear when it comes to harmful gases from coolants. Some hydrochlorofluorocarbons HCFCs , transitional substitutes that are less damaging but still harmful to ozone, are still in use. Developing countries need funding from the Montreal Protocol's Multilateral Fund to eliminate the most widely used of these, the refrigerant R The next generation of coolants, hydrofluorocarbons HFCs , do not deplete ozone, but they are powerful greenhouse gases that trap heat, contributing to climate change.
Though HFCs represent a small fraction of emissions compared with carbon dioxide and other greenhouse gases , their planet-warming effect prompted an addition to the Montreal Protocol, the Kigali Amendment , in The amendment, which came into force in January , aims to slash the use of HFCs by more than 80 percent over the next three decades.
In the meantime, companies and scientists are working on climate-friendly alternatives, including new coolants and technologies that reduce or eliminate dependence on chemicals. All rights reserved.
Climate Ozone Depletion The ozone layer helps to protect life from harmful ultraviolet radiation. Find out what caused the ozone hole, and how the Montreal Protocol sought to put an end to ozone depletion.
Ozone threats and 'the hole' In , Mario Molina and Sherwood Rowland , two chemists at the University of California, Irvine, published an article in Nature detailing threats to the ozone layer from chlorofluorocarbon CFC gases. Share Tweet Email. Read This Next Wild parakeets have taken a liking to London.
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Reduced ozone levels as a result of ozone depletion ozone depletion A chemical destruction of the stratospheric ozone layer beyond natural reactions. Stratospheric ozone is constantly being created and destroyed through natural cycles.
Various ozone-depleting substances ODS , however, accelerate the destruction processes, resulting in lower than normal ozone levels. UVB is a kind of ultraviolet light from the sun and sun lamps that has several harmful effects.
It is a cause of melanoma and other types of skin cancer. It has also been linked to damage to some materials, crops, and marine organisms. The ozone layer protects the Earth against most UVB coming from the sun. It is always important to protect oneself against UVB, even in the absence of ozone depletion, by wearing hats, sunglasses, and sunscreen. However, these precautions will become more important as ozone depletion worsens. Studies have shown that in the Antarctic, the amount of UVB measured at the surface can double during the annual ozone hole.
Addressing Ozone Layer Depletion. Laboratory and epidemiological studies demonstrate that UVB causes non-melanoma skin cancer and plays a major role in malignant melanoma development.
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