UN Scientists say Ozone Layer Depletion has Stopped

• Chillax wrote on 2010-09-17 04:24

  The "Scientific Assessment of Ozone Depletion 2010" report said a 1987 international treaty that phased out chlorofluorocarbons (CFC) -- substances used in refrigerators, aerosol sprays and some packing foams --- had been successful.
  
  Ozone provides a natural protective filter against harmful ultra-violet rays from the sun, which can cause sunburn, cataracts and skin cancer as well as damage vegetation.
  
  First observations of a seasonal ozone hole appearing over the Antarctic occurred in the 1970s and the alarm was raised in the 1980s after it was found to be worsening under the onslaught of CFCs, prompting 196 countries to join the Montreal Protocol.
  
  "The Montreal Protocol signed in 1987 to control ozone depleting substances is working, it has protected us from further ozone deplation over the past decades," said World Meteorological Organisation head of research Len Barrie.
  
  "Global ozone, including ozone in the polar region is not longer decreasing but not yet incresing," he told journalists.
  
  The 300 scientists who compiled the four yearly ozone assessment now expect that the ozone layer in the stratosphere will be restored to 1980 levels in 2045 to 2060, according to the report, "slightly earlier" than expected.
  
  Although CFCs have been phased out, they accumulated and persist in the atmosphere and the effect of the curbs takes years to filter through.
  
  The ozone hole over the South Pole, which varies in size and is closely monitored when it appears in springtime each year, is likely to persist even longer and may even be aggravated by climate change, the report said.
  
  Scientists are still getting to grips with the complex interaction between ozone depletion and global warming, Barrie explained.
  
  "In the Antarctic, the impact of the ozone hole and the surface climate is becoming evident," he said.
  
  "This leads to important changes in surface temperature and wind patterns, amongst other environmental changes," Barrie added.
  
  CFCs are classified among greenhouse gases that cause global warming, so the phase out "provided substantial co-benefits by reducing climate change," the report found.
  
  Barrie estimated that it had avoided about 10 gigatonnes of such emissions a year.
  
  However, the ozone-friendly substances that have replaced CFCs in plastics or as refrigerants - hydrochlorofluorocarbons (HCFCs) and hydrofluorocarbons (HFCs) -- are also powerful greenhouse gases.
  
  HFCs alone are regarded as 14,000 times more powerful than carbon dioxide (CO2), which is the focus of international efforts to tackle climate change, and HFC emissions are growing by eight percent a year, according to UN agencies.
  
  "This represents a further potential area for action within the overall climate change challenge," said UN Environment Programme chief Achim Steiner in a statement.

  
  
  Source: UN scientists say ozone layer depletion has stopped
• abc33kr wrote on 2010-09-17 04:51
  yay
• Phunkie wrote on 2010-09-17 11:01
  Oh that's hot.
  
  Though we need to keep researching.
• Drifter wrote on 2010-09-17 11:07
  So we can start using hairspray again?
  
  aw carp...
  
  /big hair trend returns
• Yogurticecream wrote on 2010-09-17 12:05
  Hair gel not hairspray =.=
• Magenera wrote on 2010-09-17 13:00
  Global warming wasn't that big of a issue anyway, earth always have a big CO2 rise before an Ice age hits anyway. Though having a renewable source, and helping the environment was a good thing, cause pollution is still our major problem.
• Phunkie wrote on 2010-09-17 14:03
  It depends on how you view data. Sure, CO2 increases after centuries and it's true--as you said--that Ice Ages make the concentration go down, but we've had some of the highest temperature increases ever in the past century. That does have some sort of impact.
  
  I mean, polar bears are drowning in teh Arctic. Global warming is a big issue. We just need to see how significant it really is.
• Iyasenu wrote on 2010-09-17 15:33

  Quote from Phunkie;158766:

  It depends on how you view data. Sure, CO2 increases after centuries and it's true--as you said--that Ice Ages make the concentration go down, but we've had some of the highest temperature increases ever in the past century. That does have some sort of impact.
  
  I mean, polar bears are drowning in teh Arctic. Global warming is a big issue. We just need to see how significant it really is.

  
  
  i thought polar bears could swim D:
  
  but on topic, even if the ozone level has stopped dropping, i don't think we should go overboard on things that affect it negatively xD
  
  I mean, it can't be good.
• Chillax wrote on 2010-09-17 16:20

  Quote from Magenera;158744:

  Global warming wasn't that big of a issue anyway, earth always have a big CO2 rise before an Ice age hits anyway. Though having a renewable source, and helping the environment was a good thing, cause pollution is still our major problem.

  
  
  Global warming=/=Ozone layer depletion
• wolfram wrote on 2010-09-17 16:40
  Mentions ozone layer and discuss more global warming.
  
  If we're just replacing CFL's, a global warming gas, with HFC's, a stronger global warming gas, how is this helping us?
  Ah, potential area for action says the UN. Asking for more money to do more "studies" is more likely.
• Chillax wrote on 2010-09-17 20:15

  Quote from wolfram;158813:

  Mentions ozone layer and discuss more global warming.
  
  If we're just replacing CFL's, a global warming gas, with HFC's, a stronger global warming gas, how is this helping us?
  Ah, potential area for action says the UN. Asking for more money to do more "studies" is more likely.

  
  
  CFCs were replaced by HFCs because CFCs were found to be very harmful to the ozone layer.
  
  CFC=harmful to ozone layer (more UV radiation from sun), not as strong of a greenhouse gas
  HFC=strong greenhouse gas (global temperature increase), not as harmful to ozone layer
  
  Ozone layer depletion and global warming are not one and the same, although some gases may affect both. At the moment, it's a toss-up between the two.
• Spartaaaaa wrote on 2010-09-17 21:46

  Quote from Chillax;158809:

  Global warming=/=Ozone layer depletion

  
  
  If I'm not mistaken, wouldn't more UV light cause temperatures to go up to some extent?
• Chillax wrote on 2010-09-17 23:01

  Quote from Spartaaaaa;158977:

  If I'm not mistaken, wouldn't more UV light cause temperatures to go up to some extent?

  
  
  That depends on whether the UV light gets converted into heat energy. I don't know the exact conversion process.