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Science

Upper Ozone Depletion Declining 58

Posted by timothy 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."
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Upper Ozone Depletion Declining More

Upper Ozone Depletion Declining

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  • Misunderstanding (Score:4, Insightful)

    by Dibblah ( 645750 ) on Wednesday July 30, 2003 @11:14AM (#6570817)
    No. It's an example of us stopping screwing it up quite so quickly.
    The rate of depletion has slowed != everything's OK again.

    • Re:Misunderstanding (Score:2, Informative)

      by TripleA ( 232889 )
      Exactly, the ozone layer is still getting thinner.
    • Who said everything's okay again? Not me.

      If you want to argue that slowing destruction != reversing it, that would be a more reasonable point to make. But I believe we're in agreement.

    • Re:Misunderstanding (Score:4, Insightful)

      by mlush ( 620447 ) on Wednesday July 30, 2003 @11:28AM (#6570953)
      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.

      • Second world? That being? For me, the second world is North America.
        • Second world? That being? For me, the second world is North America.

          From here [nationsonline.org]

          The origin of the terminology is unclear. In 1952 Alfred Sauvy, a French demographer, wrote an article in the French magazine L'Observateur which ended by comparing the Third World with the Third Estate: "ce Tiers Monde ignore, exploite, meprise comme le Tiers Etat" (this ignored Third World, exploited, scorned like the Third Estate). Other sources claim that Charles de Gaulle coined the term Third World, maybe de Gaulle only

    • i spoze....but less is still better than a steady attack on the o3 i say......ok, that's about it.

    • Re:Misunderstanding (Score:3, Insightful)

      by den_erpel ( 140080 )
      From the article:

      "We're not gaining ozone, we're just losing it less quickly," he said. Between 1997 and 2000, the average growth rate of the ozone hole has slowed by approximately 7 percent per decade, according to their calculations. It will take at least 40 or 50 years before all the ozone depletion stops and recovery begins, Newchurch said.

      Let's not get our hopes up, 40 years until recovery begins, we are still going down... It makes you wonder how long it will take before the effects of global warm

    • One person with one aerosol can of CFCs cannot do much damage to the ozone layer. However, 300 million people, each having 1 aerosol can, can significantly destroy the ozone layer.

      What's the population of the globe? 6 billion?

      Multiply the polluting effects of 1 person by a factor of 6 billion. 6 billion people would eat all the fish in the oceans, clog the atmosphere with CO2 (worsening a greenhouse effect) from billions of automobiles, etc. Get the picture?

  • When people's ozone depletion increases, ozone decreases.
    When Ozone decreases, people die faster.

    Logical assumption: There is an equilibrium between how much ozone there is, and population of people.

    Guess: It doesnt matter.

    • Re:Simple, really.... (Score:3, Interesting)

      by HaloZero ( 610207 )
      It's cyclic.

      Earth. Ozone layer allows birth and flourishment of homo sapiens.
      Homo sapiens irradicate ozone layer through flourishment.
      Loss of ozone layer results in irradication of homo sapien population.
      Ozone layer returns gradually after eons of non-interference by now-extinct homo sapiens.

      However, I do suppose this is excluding whatever damage the gradual decay of our structures and chemical shit (sun no longer stopped by now non-existant ozone - what will react?) will do to retard the reintroduction o

  • less damage (Score:3, Insightful)

    by patch-rustem ( 641321 ) on Wednesday July 30, 2003 @11:21AM (#6570884) Homepage Journal
    ... 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?
    • Does less wrong make a right?
      You ever hear the saying "you need to crawl before you can walk?"

      Yes, less bad is good. But then, I guess I'm a highly paid genious so this sort of logic comes easily to me.
      • I think that is the greateset irony. When someone claims to be a genius yet spells the word genius wrong.

        I aM vEarY SmArrT, maykes Mee Happee!

        • I think that is the greateset irony. When someone claims to be a genius yet spells the word genius wrong.

          Isn't it though? The entire statement was sarcastic . You see, by claiming myself to be a 'highy paid genius' I was not necessarily claiming to be above normal intellect, but simply that much more intelligent than the person to whom I responded (seeing that I *get* the simple logic that less bad is good). Thereby moving them *down* rather than me *up*. Get it? I guess not...

          /. is too serious som

  • OR.... (Score:5, Interesting)

    by Picass0 ( 147474 ) on Wednesday July 30, 2003 @11:39AM (#6571036) Homepage Journal

    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.

    • Re:OR.... (Score:5, Insightful)

      by drlock ( 210002 ) on Wednesday July 30, 2003 @12:45PM (#6571639) Homepage
      I have the same question.

      According to this article [nasa.gov], "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 [dxlc.com].

      So how can we prove that it was the meager efforts of us humans that made the change, and not just a natural cycle?

      • Re: (Score:2, Insightful)

        by account_deleted ( 4530225 )
        Comment removed based on user account deletion

        • Re:OR.... (Score:3, Informative)

          by KnightNavro ( 585943 )
          You can break out the "no proof" card for global warming, but ozone depletion is pretty well proven. The chemical mechanism is well documented and demonstrated.
          • But this seems to be the jump in logic that I am questioning. That this "chemical mechanism" can happen does not mean that it is or that humans are the primary cause.

            In most global warming / ozone arguments that I read there seems to me to be a large jump in reasoning between 'we have made this happen in the lab' and 'this is THE cause for ...' I have seen very few articles where people are actually testing the ozone and the reactions there.
            • First off, don't ever combine ozone and global warming into the same debate. They're two entirely different subjects. Ozone depleting reactions are well documented and demonstrated, but greenhouse effects are only theory and modeling.

              Here's the way it is...

              Man makes CFC's. They aren't found in nature. The banned ones are very stable and migrate throughout the atmosphere. Just because they're heavier than air doesn't mean they stay close to the ground. If that were the case, we'd walking in a thick

          • You can break out the "no proof" card for global warming, but ozone depletion is pretty well proven. The chemical mechanism is well documented and demonstrated.

            I heartily disagree, and yes IAC (I am a chemist :>). The mechanism is proven, but the problem is that atmospherics and fluid dynamics that keep the radical species concentrated near the poles. Basically what happens is that long-term-stable weather patterns set up, keeping the nasties bottled up. However, these things do change eventually, l

        • Environmentalists don't need any so-called "facts" or "proof". The fact that they've managed to convince so many people that the ozone hole is humanity's fault, with so little proof, is quite amazing, actually.

          There is solid evidence that ozone depletion is due in part to human activity. Of course like many scientific facts that doesn't suit the nutjob libertoonians, so they pretend that it doesn't exist. Let's see, who should we believe, a couple of right-wing fanatics on the internet, or legitimate c

          • Answer: (Score:3, Insightful)

            by ckaminski ( 82854 )
            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...

            • Re:Answer: (Score:4, Insightful)

              by nomadic ( 141991 ) <`nomadicworld' `at' `gmail.com'> on Wednesday July 30, 2003 @05:48PM (#6574539) Homepage
              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.
              • Something I'm not debating. But I've learned that just because someone has credentials, doesn't mean their competent, and just because someone is a hobbyist, doesn't mean they don't know more than that PhD teaching our next generation of students.

                There will always be people manipulating data for their own agendas, I was attacking the supposition that simply because someone is credentialed, doesn't immediately make them more voracious than someone who is not.

                But thanks for the bit of common sense. :-)
              • Actually there are fools on both sides that cling to what ever facts that fit their ideology. I saw a keep space free for peace talk once that had so much bad science that it made my head hurt. Not to mention enough BS to grow a field of corn that could feed a small country.

                Once you are sure that you are always "open minded" you most likley are not. I find it best to always try to disprove what I believe. It is all to easy to to prove it to yourself.

          • Re:OR.... (Score:2, Interesting)

            by DavidTC ( 10147 )
            Have you even ever looked at how CFCs are claimed to work? Check it out, it's completely nonsensical.

            All the crappy science out there will talk about how ozone is 'destroyed', when, of course, CFCs are just turning it into O2, which is all that's up there to start with, sans radiation.

            And there's plenty of proof the ozone layer doesn't fucking care...strip away some ozone, more radiation will get through, it will hit O2, and you'll get more O3 to stop the radiation. Duh!

            Meanwhile, there's plenty of evid

            • Re:OR.... (Score:3, Informative)

              by Jazu ( 215175 )
              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

              • Re:OR.... (Score:2, Insightful)

                by DavidTC ( 10147 )
                Except that there's already plenty of stuff up there turning O3 into O2 + O, it's not just sunlight. So in reality what you're talking about in the first cycle happens maybe half the time, and the maybe we dumped enough CFCs into the air to make that cycle happen, instead, 10% of the half of the time. (Which is an amazing amount of CFCs to get up there, but whatever.)

                And the second cycle doesn't show fewer rays hitting anything...it shows fewer rays hitting per cycle. As there are the same amount of rays c

                • The way to create ozone is to break an O2 molecule. This happens at short UV wavelengths, around 200 nm (blue light is around 360, red around 700). Ozone absorbs UV light as long as 320 nm or so.

                  This means that decreasing the amount of ozone leads to an increase of longer wavelength UV, which can make it to the ground and lead to skin cancer, dead baby frogs, etc. Decreasing the amount of ozone has no effect on the wavelengths which break up oxygen molecules and create ozone in the first place.

      • Re:OR.... (Score:2, Insightful)

        by DjReagan ( 143826 )
        > So how can we prove that it was the meager efforts of us humans that made the change, and not just a natural cycle?

        Maybe it was, maybe it wasn't. But surely thats no reason for us to avoid doing things that we know will fuck it up to some extent?

      • Re:OR.... (Score:2, Informative)

        by ndinsil ( 454614 )

        So how can we prove that it was the meager efforts of us humans that made the change, and not just a natural cycle?

        The same way we can prove the "meager" efforts of humans started the problem in the first place. See, for example, this FAQ [noaa.gov] that lays out the argument. In addition, you should probably have continued your quote of that article, where it says "Sunspot variations only account for 2 to 4 % of the total variation in ozone concentrations."


    • > 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.

      Yes, and perhaps 'intelligent' species arise and pollute themselves to extinction in natural cycles too. Wanna play?

    • Different ozone (Score:5, Informative)

      by hcetSJ ( 672210 ) on Wednesday July 30, 2003 @03:58PM (#6573510)
      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...
    • Comment removed based on user account deletion

  • Doing My Part (Score:3, Funny)

    by 4of12 ( 97621 ) on Wednesday July 30, 2003 @11:49AM (#6571109) Homepage Journal

    nice example of humans taking an active role

    People in L.A. have been doing their part, drivign their cars in the sunshine, to help create more ozone!

    Now if we could only get it off the ground and up high we'd have it made.

    As a side note, the high flying SSTs, such as the Concorde, have stopped in the last few years.

  • Thank Mrs. Claus for that one (Score:3, Funny)

    by Dancin_Santa ( 265275 ) <DancinSanta@gmail.com> on Wednesday July 30, 2003 @12:55PM (#6571740) Journal
    She's changed Tuesday's menu from Mexican burritos to Tofu burgers.

    The elves are breathing a little easier on Wednesday mornings.

  • can you prove this hypothesis? (Score:5, Funny)

    by DrSkwid ( 118965 ) on Wednesday July 30, 2003 @01:10PM (#6571858) Journal
    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?"

  • Where's the link? (Score:1, Interesting)

    by DrPeper ( 249585 )
    I don't remember ever seeing conclusive evidence (as in studies) that aerosol use was ever positively linked to the depletion of the ozone layer. In fact I remember several studies highlighted on the discovery channel which cast quite a bit of doubt on that that hypothesis.
    • While you're waiting for your absolute, proof-positive, without-a-single-shred-of-doubt, conclusive, unassailable evidence, keep repeating this phrase: "Melanoma is my friend. Melanoma is my friend..."

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