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Upper Ozone Depletion Declining

Posted by timothy on from the better-than-increasing dept.

Silas writes "This SF Chronicle article (and many others) reports that destruction of the upper part of Earth's ozone layer has slowed because of the international effort more than a decade ago to ban ozone-damaging aerosols. More about the study and techniques used is here. We're still a long way away from recovery, but it's a nice example of humans taking an active role in reversing some of the damage we've done."

12 of 58 comments (clear)

  1. Misunderstanding by Dibblah · · Score: 4, Insightful

    No. It's an example of us stopping screwing it up quite so quickly.
    The rate of depletion has slowed != everything's OK again.

    1. Re:Misunderstanding by mlush · · Score: 4, Insightful
      No. It's an example of us stopping screwing it up quite so quickly.

      It is however a good sign, we may have to wait for decades to see ozone levels rising. This news keeps the pressure on to eleminate production of ozone destroying CFC... there still being used in the second and third world.

  2. less damage by patch-rustem · · Score: 3, Insightful
    ... a nice example of humans taking an active role in reversing some of the damage we've done.
    It's not reversing damage. It's increasing the damage at a reduced rate.
    Does less wrong make a right?
    --
    Karma: Bad due to google bombing - Robert Watkins woz 'ere.
  3. OR.... by Picass0 · · Score: 5, Interesting


    Could it just be that with our very limited (~40 years worth) sample of scientific data that we just do not have a very good understanding of how the cycles of the Ozone Layer work? Perhaps ozone holes occur and disappear naturally, and we are only beginning to learn this. Ozone is created every time lighting strikes the earth (about 100 time every second) so ozone is not something that goes away forever.

    1. Re:OR.... by drlock · · Score: 5, Insightful

      I have the same question.
      According to this article, "Since ozone is created and destroyed by solar UV radiation, there is some correlation of ozone concentration with 11-year sunspot cycles." (article also give a number of other natural causes of ozone layer change). The SF Chronicle said, "Between 1997 and 2000, the average growth rate of the ozone hole has slowed by approximately 7 percent per decade" That was the exact period of a spike in sunspot activity.
      So how can we prove that it was the meager efforts of us humans that made the change, and not just a natural cycle?

    2. Re:OR.... by Jazu · · Score: 3, Informative

      Here's how this works.
      Without chlorine:
      1. UV ray hits O2. O2 -> O + O
      2. 2O + 2O2 -> 2O3
      3. 2 UV rays hit 2O3. 2O3 -> 3O2
      Steps 1-3 repeat ad infinitum, 3 UV rays are absorbed in each cycle.

      With chlorine:
      1. 2 UV rays hit 2 CFCs. CFCs lose 2Cl, rest of CFC molecules are inert.
      2. UV ray hits O2. O2 -> O + O
      3. 2O + 2O2 -> 2O3
      4. 2Cl + 2O3 -> 2ClO + 2O
      5. 2ClO + 2O -> Cl + O2

      Repeat steps 2-5 ad infinitum. 2 extra rays are absorbed in the beginning, but in the repeating reaction, 1/3 fewer UV rays are absorbed if chlorine interferes. Sorry, I don't see the nonsense.

      --
      My joke got modded as Insightful and my insight got modded as Funny.
  4. Thank Mrs. Claus for that one by Dancin_Santa · · Score: 3, Funny

    She's changed Tuesday's menu from Mexican burritos to Tofu burgers.

    The elves are breathing a little easier on Wednesday mornings.

  5. can you prove this hypothesis? by DrSkwid · · Score: 4, Funny

    but it's a nice example of humans taking an active role in reversing some of the damage we've done.

    "How's the anti-elephant cream coming along?"

    "Can *you* see any elephants?"

    --
    There are places where the networks are not touching,and there are places where they are-Boeing's Lori Gunter
  6. Re:Chemistry Question by Guy+Harris · · Score: 4, Informative
    How does a chlorofluorocarbon molecule, which is heavier than air, affect the Earth's upper atmosphere at the poles? Responses with detailed analyses are appreciated. Please limit your responses to 500 words.

    OK, how about one URL (to a page whose word count I'm not going to bother computing) for a page entitled How Can Chlorofluorocarbons (CFCs) Get to the Stratosphere If They're Heavier than Air?.

  7. Different ozone by hcetSJ · · Score: 5, Informative

    Ozone created from lightning is different from the ozone in the ozone layer. How? Well, it's not in the ozone layer (nor would it really make its way there). Having ozone at ground level is a problem--particularly for asthma sufferers and the like--so ozone from lightning (or arc welding, for that matter) isn't going to help.

    Of course, if one were to arc weld while riding an SR-71...

    --

    This side up.
  8. Answer: by ckaminski · · Score: 3, Insightful

    Both should be taken with a healthy dose of skepticism and analytical thinking and extensive fact checking should follow.

    But nah, we're too lazy for THAT...

    1. Re:Answer: by nomadic · · Score: 3, Insightful

      Actually on the science side they're constantly re-examining the answers they come up with. It's the anti-environmental side who cling to whatever "facts" they think fits in with their ideology.