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Earth Science

Over the Antarctic, the Smallest Ozone Hole In a Decade 174

hypnosec writes "The ozone layer seems to be on a road to recovery over Antarctica; according to Europe's MetOp weather satellite, which is monitoring atmospheric ozone, the hole over the South Pole in 2012 was the smallest it's been in the last 10 years. The decrease in size of the hole is probably the result of reduction in the concentration of CFCs, especially since the mid-1990s, because of international agreements like the Montreal Protocol."
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Over the Antarctic, the Smallest Ozone Hole In a Decade

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  • Re:HypnoToad says (Score:5, Informative)

    by K. S. Kyosuke ( 729550 ) on Sunday February 10, 2013 @03:40PM (#42851927)
    Except that these processes are simple enough that we can measure the high altitude concentrations of these compounds and show that their influence on the O3 concentration closely matches our understanding of the processes involved.
  • by Anonymous Coward on Sunday February 10, 2013 @04:07PM (#42852161)
    No. The hole in the ozone is caused by chlorine in the stratosphere, which gets there in chloroflorocarbons, catalyzing the O3 generated by the radiation in the upper atmosphere. It has nothing to do with climate change or greenhouse gasses.
  • Re:Non-story? (Score:5, Informative)

    by fuzzyfuzzyfungus ( 1223518 ) on Sunday February 10, 2013 @04:12PM (#42852219) Journal

    Surely if it's been shrinking all this time then you could have the same story every day: "ozone hole smallest size since $date". Has it grown occasionally for some reason?

    For reasons that are sufficiently messy that I certainly couldn't do them justice(and there really isn't any point in copy/pasting a pretend understanding from wikipedia and just wasting space) ozone levels vary considerably over time, both because of natural seasonal weather patterns and because of changes in the presence of various ozone-depleting synthetic compounds.

    My understanding is that trends on atmospheric concentration of more or less all of the really nasty ozone-depleting compounds have been positive since regulation went into effect; but that the size and shape of the ozone hole has been a great deal more chaotic from season to season(shape counts, for our purposes, because ozone thinning over the antarctic is a bad sign; but the number of epidemiologists who care about penguin melanoma is limited, while ozone thinning over Australia is directly troublesome).

  • Re:HypnoToad says (Score:3, Informative)

    by Pino Grigio ( 2232472 ) on Sunday February 10, 2013 @07:07PM (#42853747)
    I did read a paper not so long ago about the Ozone layer being regulated to a large degree by cosmic rays, over the Antarctic [uwaterloo.ca].

    And by the way, moderating dissenting voices "troll" is totally beyond the pale. Science is about skepticism. Physicists are highly skeptical of each other's results. When it comes to Earth Sciences, why is it that people crowd the paradigm like it's a sacred tome? Debates here would be far more interesting if they were actually allowed.
  • Re:Sigh (Score:5, Informative)

    by radtea ( 464814 ) on Sunday February 10, 2013 @07:45PM (#42854045)

    You are a denier. Because you put "economics" a.k.a short term profits first. Basically you say "If I cannot earn money polluting, fuck you".

    And the Lack of Reading Comprehension Award goes to the guy who wrote the above, putting words in the GP's mouth and then maligning them on the basis of that fantasy.

    It's so much easier to win arguments with imaginary opponents who can be vilified for saying outrageous things.

    With regard to economics: while it does not explain all of human behaviour, it is difficult to defend the hypothesis, beloved by Lefties in particular, that "economics doesn't matter".

    Economics matters, and it is not "putting economics first" to say this, but rather recognizing that economics imposes constraints on any solution to the problem of anthropogenic climate change. The anti-AGW community are firmly convinced that the pro-AGW community consists solely of people like you, who think that the reality of AGW is somehow justification to impose your own anti-economic agenda on the rest of the world.

    By responding as you are, you are playing exactly the role the anti-AGW community wants you to play, bolstering their support amongst the public, who will see you for what you are: a left-wing nutjob who has grabbed on to the AGW mantra as an excuse to further your political agenda, not because you care about the future of the planet (because as the GP correctly points out, any viable solution to AGW will have to take economic constraints into account, as as such people like you who deny economic constraints are important are actually an impediment to dealing with AGW.)

  • Re:Sigh (Score:5, Informative)

    by rastoboy29 ( 807168 ) on Sunday February 10, 2013 @08:47PM (#42854479) Homepage
    It has been proven beyond a *reasonable* doubt.

    The reason banning CFC's was so easy was because it was a relatively small target, and replacement technology was almost immediately available.

    The reason there is so much noise about climate is because it affects *everything* and there is no cut and dried solution available.  Entrenched interests have been pouring money into FUD on the scientists themselves for years for that reason.  And because they are suicidal, apparently...
  • Re:HypnoToad says (Score:3, Informative)

    by russotto ( 537200 ) on Sunday February 10, 2013 @09:40PM (#42854773) Journal

    It was urgent that CFCs be phased out not because of atmospheric damage but because DuPont's patents on them were about to expire.

    That's bullshit. R-12 and R-22 were long out of patent by the time the phaseout started.

    Anyone who works with refrigerants knows how "fucked" the replacements are compared to their predecessors.

    That, unfortunately, is true.

  • Re:HypnoToad says (Score:5, Informative)

    by Electricity Likes Me ( 1098643 ) on Sunday February 10, 2013 @11:27PM (#42855351)

    Good job misrepresenting that. Here, let me post the abstract, literally the first thing you'd read:

    This Letter reports reliable satellite data in the period of 1980–2007 covering two full 11-yr cosmic ray (CR) cycles, clearly showing the correlation between CRs and ozone depletion, especially the polar ozone loss (hole) over Antarctica. The results provide strong evidence of the physical mechanism that the CR-driven electron-induced reaction of halogenated molecules plays the dominant role in causing the ozone hole. Moreover, this mechanism predicts one of the severest ozone losses in 2008–2009 and probably another large hole around 2019–2020, according to the 11-yr CR cycle.

    The paper does not say it's dependent on cosmic rays exclusively, instead it points out that cosmic ray activity seems to play a significant role in determining the activity of halogenated molecules destroying ozone. Guess which one of those parameters we've totally screwed around with from the 1970s onwards?

    I'll give you a hint: it's not cosmic ray irradiation.

  • Re:HypnoToad says (Score:3, Informative)

    by at0mjack ( 953726 ) on Monday February 11, 2013 @01:25PM (#42861037)

    *sigh*. If you're going to quote the scientific literature in support of your argument, you need to at least make some effort to understand it first.

    The paper says that cosmic rays strongly correlate with ozone depletion. The data point to cosmic-ray driven reactions of halogenated molecules as being the cause of the correlation. The *only* halogenated molecules present in the stratosphere in any significant concentration are CFCs. I'll repeat that: where the paper talks about "halogenated molecules", it's talking about CFCs, HCFCs and other man-made chemicals.

    Hence, this paper is presenting an alternative explanation to *why* CFCs damage the ozone layer. The prevailing hypothesis is that photolysis of CFCs (i.e. UV from the sun breaking them apart) is what kicks off the ozone-depleting catalytic cycle. This paper says "Nah, it's not photolysis, it's cosmic-ray-induced ionisation of the CFCs that sets the whole thing off".

    From the paper:

    In the CR-driven mechanism, the O3 -depleting reactions depend on halogen concentrations, CR intensity, and PSC ice (to hold the electrons) in the stratosphere [6,8]. From 1992 up to now, the Antarctic O3 loss has shown a clearest correlation with the CR intensity. This is because the total halogen amount of the stratosphere, particularly those of CFCs, is nearly constant in that period of time [30]; thus the regulating effect of CRs on O3 loss becomes manifest. In contrast, such a time correlation is hardly seen in the enlarging spring polar O3 loss during 1980s, since at that period of time, the halogen loading increased dramatically and thus ozone showed a drastic decreasing trend blurring the CR-O3 loss correlation. And in the pre-1980s, no significant halogen loading was found in the stratosphere, and thus no significant O3 loss was observed.

    Summarising that: since 1992, there's been loads of CFCs in the atmosphere, and hence the rate-limiting step in how much ozone gets broken down is how many cosmic rays there are. Before 1980, there were no CFCs in the stratosphere, and hence cosmic rays didn't destroy any ozone. Your bet is thus meaningless: this paper is part of the argument over *why* CFCs cause ozone depletion, not *whether*.

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