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Signs of Ozone Layer Recovery Detected

polar red writes "22 years of banning CFCs is starting to pay off. Researchers have finally been able to measure a reduction in size of the ozone layer hole, after finding the source of its fluctuations. 'Salby's results reveal a fast decline in ozone levels until the late 1990s, then a slow rebound that closely matches what theoretical calculations had predicted, says David Karoly, a climate scientist at the University of Melbourne, Australia. "It is the sort of result that was expected, but is the first to provide detection of an increase in Antarctic ozone levels," he says.'"

45 of 363 comments (clear)

  1. Climate Change Deniers by Drake42 · · Score: 3, Insightful

    Why is it that the scientists can detect an ozone hole, provide a fix, show that the fix solved the problem, and then be LOUDLY IGNORED by the liars in congress.

    Oh. The CFL manufacturers had less money than the oil people. Sorry. I forgot...

    1. Re:Climate Change Deniers by 0123456 · · Score: 4, Interesting

      The CFL manufacturers had less money than the oil people. Sorry. I forgot...

      Didn't the 'ozone hole' only become an OH MY GOD WE'RE GOING TO DIE problem after the patent on CFCs in air conditioning expired?

    2. Re:Climate Change Deniers by Mindcontrolled · · Score: 5, Insightful

      You know, when there is a physical mechanism connecting two phenomena AND a correlation between them, that correlation != causation thing is simply, well, bullshit.

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    3. Re:Climate Change Deniers by tibit · · Score: 3, Informative

      Now be careful. The CFC replacements are potent greenhouse gases. Potent as in 3 orders of magnitude worse than CO2. Is it better to die of skin cancer, or of hunger due to crop failures due to draught due to raising global temperature? I don't know...

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    4. Re:Climate Change Deniers by tibit · · Score: 3, Interesting

      Global warming is caused by the emission of gases, mostly CO2, but also CFC replacements that are 1000s of times more potent than CO2.

      Fixed that for ya. Apparently Nature doesn't provide free lunches :(

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    5. Re:Climate Change Deniers by Mascot · · Score: 2

      I seem to recall there being scientists back then arguing "CFC or no CFC, this will fix itself given a few decades, no reason to panic". By your logic, should we now believe whatever those people state?

      The point I'm trying to make, as others have: correlation != causality.

    6. Re:Climate Change Deniers by Solandri · · Score: 5, Insightful

      It's because most of the evidence supporting global warming thus far is comprised of correlation studies. As I like to say, a good correlation paper can win you a high school science fair. A good causation paper can win you the Nobel prize. Which is precisely what happened with ozone depletion. A trio of scientists came up with an elegant, predictive, and empirically accurate mechanism to explain exactly how ozone depletion was occurring, and won the Nobel prize in Chemistry for it.

      Come up with a comprehensive, predictive, and empirically accurate model for climate change, and you will probably win the Nobel prize (in something like physics, not a trophy prize like peace) and simultaneously convince the world's government that they must act. The problem with correlation studies is that they're always open to dispute since you never identify or test the actual mechanism causing the problem. That's what happened with cigarettes - for decades the medical community had tons of correlation studies saying that smoking was bad. But the government restrictions and bans didn't come about until medical researchers began to identify and confirm the mechanisms by which smoking was causing cancer.

    7. Re:Climate Change Deniers by Mindcontrolled · · Score: 4, Informative

      The causation paper for climate change would win you zilch at all, since the basic mechanism has been published by Arrhenius about 130 years ago. All the open questions are more in the realm of systems theory, not in the realm of basic mechanisms.

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    8. Re:Climate Change Deniers by cryptolemur · · Score: 5, Informative

      Oddly enough climate change is something that comes out of the physics models when you put in what we understand of the climate. It has nothing to do with correlation, it's pure mechanical causation. As it happens, the observations do confirm the model.

      And it also happens, that the exact same people who were arguing against CFC -> Ozone hole causation and smoking -> lung cancer causation started arguing against climate change. They obviously can fool some of the people all of the time.

      Oh, and the actual mechanism of how smoking causes lung cancer was partly revealed a few year back, but is still not completely understood.

    9. Re:Climate Change Deniers by bunratty · · Score: 2

      Carbon dioxide is a greenhouse gas. The causation is trivial. That's why global warming was predicted long before it was observed.

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    10. Re:Climate Change Deniers by Mindcontrolled · · Score: 2

      As for the smoking -> cancer mechanism, large parts of it are known for decades. Polycyclic aromates in the smoke are potent intercalators, which put themselves between basepairs in DNA and mess with replication. Given how fast biochemistry has developed in the last century, that mechanism is positively prehistoric. There are other mechanisms, some of which have been found more recently, but the basics are known for ages.

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    11. Re:Climate Change Deniers by Mindcontrolled · · Score: 2

      Maybe your infrastructure just sucks? I live in the first world, personally. In particular, in a country that hasn't let its grid go to shit for some decades. All I see is overcapacities. But you don't really want to argue about the possibility of changing the status quo, you are absolutely convinced that it should not be changed, therefor it CANNOT be changed. When your argument boils down to "electrification of commuter traffic will kill the elderly", well, then you'd better admit that you lost, before you dig yourself deeper into the bullshit.

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    12. Re:Climate Change Deniers by interkin3tic · · Score: 2

      when emotions and political leanings enter the argument it is far to often to emerge wrong, not matter how right one may be.

      You forgot economic interests. The problem with the climate change debate is NOT that there is too much emotion in it, it's that there is too much MONEY in pretending it's not real. The oil and coal industries throwing FUD against preventing climate change is precisely the problem with the debate.

      I suppose there would still be people who prefer to distrust scientists and or disreguard "treehuggers" just as there were/are still people who pretended cigarettes were perfectly healthy long after the tobacco industry stopped fooling people. Still, I think if it weren't for the lies, the debate would have been HOW to reduce carbon emissions ten years ago, not whether we should. We likely could have done it more gradually and cheaper, and had less damage done, than what we're facing now.

    13. Re:Climate Change Deniers by hedwards · · Score: 2

      You're right, there are also religious nut jobs that believe that God won't allow any flooding because the Bible doesn't foresee ones. And the libertarians that are opposed to any and all regulations on the basis of them being entitled to do whatever they like so long as there isn't an indisputable conflict with other people's rights. And then don't forget the people who don't actually have any education on the matter who are skeptics mainly because Fox News tells them to be afraid of the vast liberal conspiracy to take away their rights.

    14. Re:Climate Change Deniers by bunratty · · Score: 4, Informative

      The observation that would not fit the prediction would be little or no warming. The falsifiable hypothesis is that an increase in carbon dioxide in the atmosphere causes warming. There are literally hundreds of published scientific papers you can read about the topic. It's been a very active area of research for decades. I'll point you to just one short summary of the research results.

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    15. Re:Climate Change Deniers by riverat1 · · Score: 2

      But there 10's of thousands of times less CFC replacement gases in the atmosphere than CO2 so they are a minor component of GHG warming. By themselves they wouldn't cause enough warming to worry about. Adding them on top of CO2 and methane they don't help.

    16. Re:Climate Change Deniers by Mindcontrolled · · Score: 4, Interesting

      The radiative equilibrium between incoming sunlight and blackbody radiation for Earth would result in a temperature about 20K lower than observed, when not taking atmospheric effects into account. Accounting for absorption and reemission by atmospheric CO2 you arrive at the actual average temperature. Said spectroscopic properties of CO2 are simply measurable in the lab. I actually did the experiment in a lab session about 14 years ago - part of the physical chemistry II lab. Are you seriously questioning the existance of the greenhouse effect as such?

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    17. Re:Climate Change Deniers by BergZ · · Score: 2

      If what you meant to say was "there's an awful lot of money in convincing people that [climate change] is real too" then I'd say:
      For every dollar spent convincing people that climate change is real there is probably a hundred dollars spent trying to convince people that climate change is a myth.

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    18. Re:Climate Change Deniers by interkin3tic · · Score: 2

      Between a conspiracy of the makers of solar panels, hybrid cars, nuclear power, and hippies, and a conspiracy on the part of coal and oil, I'm much more worried about the coal and oil conspiracy. They got more money.

      Anyway, my point was mainly that economic interests confused the issue. If it goes for both sides, fine, just don't say it's all "emotion" and no logic.

    19. Re:Climate Change Deniers by the+gnat · · Score: 5, Insightful

      If you send the nation into poverty to clean the air

      I think this is the aspect of the debate that annoys me the most - the hyberbolic exaggeration of the economic effects of reduced consumption of fossil fuels. There are of course real costs involved, but nothing that scientists or mainstream policy-makers have proposed is going to cause us to sink to Third World levels of deprivation, or revert to a pre-industrial economy. Citizens of Western Europe have been living with drastically higher gasoline prices than us for decades, and they don't seem impoverished to me. Downgrading to a smaller and more fuel-efficient car is not a huge decrease in living standards relative to what the rest of the world has to endure.

    20. Re:Climate Change Deniers by interkin3tic · · Score: 3, Insightful

      If you send the nation into poverty to clean the air, people who are starving aren't going to thank you

      It is pure idiotic FUD to suggest that false dichotomy: that the only two options are 1. unrestricted global climate change or 2. economic armageddon and killing grandparents in florida.

      Only crazy drugged-out hippies would suggest shutting down all coal plants immediately. The smart thing to do would be to set gradual caps, adjust subsidies gradually, have reasonable, balanced goals. Maybe say "no NEW coal plants." The only way that produces economic ruin is if you're a coal company and refuse to diversify.

    21. Re:Climate Change Deniers by Doc+Ruby · · Score: 4, Insightful

      There is no claim that "any level of carbon in the air is too high". You made that up.

      Practically no one is saying to give up transportation or electricity. You made that up, too. Some people say we should reduce wasteful transportation and electricity consumption, make its provision more efficient.

      No one is sending the nation into poverty to clean the air. You made that up, too. The opposite is true: people are trying to save the nation from the poverty that Greenhouse pollution is creating, by investing in the clearly highly profitable improvements and replacements for our Greenhouse pollution ways.

      No one's sneering at "money". You made that up, too. There wasn't even a sneer in there, except the one you made up. Reducing carbon emissions 10 years ago, more gradually and cheaper, doing less damage than we're facing now, would have embraced money. Just not the money of the polluters. Who deserve more than a sneer - they deserve jailtime and deep fines.

      Nobody attacked your money. Unless you're profiting from Greenhouse denial or Greenhouse pollution. Which, from the pile of stuff you just made up, seems entirely likely. In which case, you deserve an attack you haven't yet gotten, as well as jailtime and deep fines.

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    22. Re:Climate Change Deniers by Doc+Ruby · · Score: 2

      China's 2011-2015 plan (its 11th 5 Year Plan) will reduce China's total energy consumption by 15%, and its total CO2(-equiv) emissions by 17%.

      By the time China deprives the US of the "but China makes our efforts moot" fallacy that (literally) smokescreens US greed and filth, it will be too late for the US to catch up to China's lead in 21st Century industrialism. Way to blow it, deniers.

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    23. Re:Climate Change Deniers by Doc+Ruby · · Score: 2

      ICE cars get about 25% efficiency from gasoline, and getting the gasoline from crude to their tanks eats at least another 7%.

      Coal plants, while filthy, still generate electricity at over 35% (up to 45%) net efficiency that electric cars consume at over 95% net efficiency. That's at least 33% efficiency from coal/electric instead of 18% efficiency from gas/crude. ICE is therefore at most 54% (or as little as 42%) as efficient as the coal/electric transportation. When coal plants capture the "waste" heat from electricity generation, the combined cycles can be even higher in net efficiency (replacing other heat generation fuel), like in IGCC up to 60% efficiency. That puts ICE at 31% of coal's efficiency; coal can be 3.16x as efficient as ICE.

      And coal plants generate their pollution centrally, where it can be collected much more efficiently than at millions of car tailpipes.

      And coal plants can be replaced by geothermal plants, either in-place or just elsewhere on the grid. Plus moving everything to electricity makes it all more fungible, so it can be more efficiently consumed wherever it's needed at the moment, instead of the waste from stockpiling and speculation on easily disrupted supply chains.

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    24. Re:Climate Change Deniers by Mindcontrolled · · Score: 2

      Besides, where ARE those hippies? Haven't met many, lately. And usually all we conspire about is bogarting the spliff...

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    25. Re:Climate Change Deniers by khallow · · Score: 2

      Why is it that the scientists can detect an ozone hole, provide a fix, show that the fix solved the problem

      It's worth noting that the complete sequence described above hasn't actually happened. Sure, an ozone hole was detected, but we don't know that human activities have played a significant role in its existence, that is, it may something that occurs anyway without human interference and hence, we are at best very limited in our ability to fix it without some large scale geoengineering project.

      Then the final claim in the sequence that the "fix solved the problem" is based on nothing but wishful thinking. Here's an alternate scenario. Ozone holes form frequently over Antarctica. We just happened to start observing when an ozone hole had formed. Now that the phenomenon is starting to close up, temporarily, we're attributing that change to our actions which didn't have an effect.

      This sort of thing is very relevant because we might see the ozone hole reestablish itself in a few years. This incidentally is what I consider an important observation. If ozone holes periodically return, then that indicates that maybe there's something wrong with the current understanding of ozone depletion models. If it never comes back, that's a solid win for the CFCs-caused-the-ozone-hole theory.

    26. Re:Climate Change Deniers by Mindcontrolled · · Score: 2

      You thoroughly refuted the hypothesis "CO2 is the only determining factor for global average temperature". Congratulations! Only, no one posits that hypothesis. Do not despair, noble Don Quixote - there are more windmills on the horizon that you can attack. Or are those even wind power plants? Charge, brave knight, CHARGE!

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    27. Re:Climate Change Deniers by williamhb · · Score: 3, Interesting

      If you send the nation into poverty to clean the air

      I think this is the aspect of the debate that annoys me the most - the hyberbolic exaggeration of the economic effects of reduced consumption of fossil fuels. There are of course real costs involved, but nothing that scientists or mainstream policy-makers have proposed is going to cause us to sink to Third World levels of deprivation, or revert to a pre-industrial economy. Citizens of Western Europe have been living with drastically higher gasoline prices than us for decades, and they don't seem impoverished to me. Downgrading to a smaller and more fuel-efficient car is not a huge decrease in living standards relative to what the rest of the world has to endure.

      But you're responding with the equally hyperbolic fallacy of assuming that the sum total of fossil fuel consumption and carbon output is people driving cars, and that just getting SUVs off the road would fix everything. The guilty secret of why western Europe's carbon output has dropped so much is because a lot of the dirty stuff like mining and manufacturing has been outsourced, and many of the economies have refocused on finance. Now, it doesn't take a rocket scientist to work out that not every country can do that: you cannot have a world that is solely populated by bankers. China's, India's, even Australia's carbon outputs meanwhile have shot up as their share of the manufacturing and mining (particularly mining in Australia's case) load has increased. Only this time we also have the additional carbon output of shipping stuff all the way around the world as nothing is made locally any more.

    28. Re:Climate Change Deniers by khallow · · Score: 3, Insightful

      when there is a physical mechanism connecting two phenomena AND a correlation between them

      Here's a simple game to try. Claim that someone has figured a relationship between two unrelated phenomena and ask an audience to guess what the connection is. Your audience will come up with numerous "physical mechanisms" for explaining the correlation they think might exist. Sure, having a physical mechanism (that is, a model for interaction in other words) and a correlation is better than a raw correlation, but it's a far cry from actual causation.

    29. Re:Climate Change Deniers by the+gnat · · Score: 4, Insightful

      But you're responding with the equally hyperbolic fallacy of assuming that the sum total of fossil fuel consumption and carbon output is people driving cars, and that just getting SUVs off the road would fix everything.

      I was cherry-picking an example; it wasn't intended to suggest a simple remedy. There are many more equally egregious wastes of energy in first-world countries; massive floodlights illuminating empty athletic fields at night are my favorite. Some of the culprits are seemingly trivial: I live in a relatively temperate climate (Northern California) where it almost never freezes, and a properly insulated residence needs minimal heating during winter. But I've ended up in several apartments or houses that were so poorly insulated that I had to choose between doubling my gas bill, or eating breakfast at 10 C. Gas is cheap, of course; insulating or rebuilding costs much more. But it isn't going to send us back to the Bronze Age; I just might have to wait another year to buy the Macbook Air. Heavily air-conditioned big-box stores are another example of extravagant waste and luxury - not that I have any moral objection to big-box stores or vapid consumerism (I also partake from time to time), but from the perspective of energy efficiency, we might as well just set gasoline on fire for fun. (Actually, we already do that: it's called NASCAR.)

      More generally, we could make much better use of renewable and/or carbon-neutral energy sources (and I do include nuclear* in this category). Yes, most of these are more expensive, but none so much that we're going to suddenly find ourselves burning garbage to stay warm. The targets proposed for carbon emissions are exceedingly modest, and more than affordable for a country with huge amounts of surplus wealth. (And I don't mean that in a tax-the-rich way: even as a grad student living on a research stipend in one of the most expensive areas in the nation, I was still able to afford a car, Internet service, plane flights home on Christmas, occasional gadgets, etc., without going into debt.) I like money too, the more of it the better, but frankly, I can afford to pay more for energy if necessary, and most of the rest of the country can as well. Unless you have an absurd sense of entitlement, this is not an apocalyptic scenario.

      I don't know what to suggest for the rapidly industrializing nations; it's much easier for us to adapt. However, it seems like the argument that "China won't cut back, so why should we?" is gaining increasing popularity. I don't think we should be using the Chinese government as a moral example for anything, let alone energy policy.

      (* including fusion, if it ever works. It's appalling that we're spending a total of more than $300 billion on the F-35 when the industrial superpowers combined can barely get their act together to build ITER for less than €20 billion.)

    30. Re:Climate Change Deniers by the+gnat · · Score: 2

      The government-funded scientists are welfare queens. They use facilities paid for by taxpayers. How much money is spent on those facilities?

      The budget of the entire US Department of Energy is approximately $25 billion, and it's by far the largest chunk spent on publicly-funded energy research. $10 billion of this is actually "nuclear security", i.e. keeping our nukes functional, which has nothing to do with global warming. The most expensive energy-research project currently in progress is the fusion reactor ITER in southern France, which is estimated to cost 16 billion Euros, split between the EU and most of the other industrial superpowers, and will take 10 years to build. The most expensive US-only project that I'm aware of is the National Ignition Facility at LLNL, which I think was around $3.5 billion, and was partly driven by its potential applicability to nuclear weapons research (as well as fusion energy).

      Oil and gas companies have some of the largest revenues in the world, including 13 of the top 50 companies (I got bored after counting that far), with a combined revenue of $2.7 trillion, which is more than the GDPs of all but a handful of nations. (They're all multinational and mostly headquartered in other countries, of course - the US-based companies account for $770 billion.) So the amount of money invested in government-funded research is orders of magnitude less than the fossil-fuels companies.

  2. Re:Too little too late by mr1911 · · Score: 5, Funny

    No, but I'll be sure to read all about it on Sunday.

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  3. Re:Omg by tibit · · Score: 2

    You're absolutely right, AC. We will. The only question is: why.

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  4. Re:CFC banning is good for ozone by bunratty · · Score: 3, Informative

    I haven't seen anyone propose "world government" for the solution to global warming. The solution put forward has been for countries to agree to reduce carbon dioxide emissions. Reducing carbon dioxide emissions will increase costs, but effects of global warming will increase costs, too. The debate is what amount of spending on reducing carbon dioxide emissions will minimize total costs.

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  5. Re:Too little too late by 680x0 · · Score: 5, Funny

    Hope your plane doesn't crash from all those flying Christians getting sucked into the jet engines.

  6. Re:can someone please explain a couple holes I see by Mindcontrolled · · Score: 4, Informative

    In a nutshell, because the thermal, i.e. kinetic energy of atmospheric molecules is way too high to get separation by weight. They are moving in random directions too fast to settle down. As for the ozone layer being where it is, yes, it is being produced up there. The layer is a dynamic process - ozone being produced from oxygen by UV activation and reacting back. You get the layer at a certain height where you have the right balance of O2 concentration and UV intensity. CFCs are a catalyst that shift that equilibrium to the side of oxygen, removing the conditions that lead to the dynamic formation of the layer in the first place.

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  7. Re:Omg by Jesus_666 · · Score: 2

    Because our bodies cease to function if certain requirements are not met. The more interesting questions are: How? And when?

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  8. Re:Some curious coincidences by Mindcontrolled · · Score: 4, Interesting

    Nice crackpot you found there. My favourite - his acid rain piece. "Decades of monitoring to detect an effect". Right. Tell that to the deforested mountain ridges in my home county that have recovered just fine after SO2 was essentially removed from coal plant exhaust. As for that nature reference - you conveniently omit that this is not a paper, but a news blurb. Serious papers on the issue? Well, rather thin in that department. I met Paul Crutzen on several occasions and had some nice talks with him. Calling him a tool of special interest lobbying is quite... off the mark.

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  9. Numbers please! by mangu · · Score: 3, Insightful

    Global warming is caused by the emission of gases, mostly CO2, but also CFC replacements that are 1000s of times more potent than CO2.

    Fixed that for ya. Apparently Nature doesn't provide free lunches :(

    No, you fixed nothing, you just failed to take into account numbers.

    CO2 isn't harmful just because it's a global warming gas. It's so harmful because it's emitted in several orders of magnitude more than other gases.

    Another gas may be 1000 times more potent, but if only a billionth as much as CO2 is being emitted, then so what?

    1. Re:Numbers please! by Layzej · · Score: 2

      Another consideration is the half life of the gas. For instance methane is quite a bit more potent as a GHG than CO2, but the half life is 7 years compared to about a century for CO2.

  10. Re:22 years of banning CFC by geekoid · · Score: 2

    Fucking troll.

    Mechanizes, evidence and prediction. They all came true. This is exactly what was predicted.

    It was CFC, and I am sick and tired of you poor excuses for a limp wristed cum stains not even bothering to look at the research and data, yes still thinking your opinion on the matter deserves equal weight in the matter. You're opinion deserves no weight on this matter, and it is provable wrong.

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  11. Re:Some curious coincidences by Mindcontrolled · · Score: 3, Interesting

    SO2 is insofar part of the subject in question as the crackpot mentioned above rants about acid rain not existing in the quoted blog. As for the references. Yes, ClOOCl photolysis under stratospheric conditions modelled in the lab is by a factor 6 lower than previously predicted. So? To quote the abstract of the paper in question: "This large discrepancy calls into question the completeness of present atmospheric models of polar ozone depletion" - true that. At no point, the basic mechanism is questioned, though. To quote the part of Rex' quote you conveniently omitted: "Overwhelming evidence still suggests that anthropogenic emissions of CFCs and halons are the reason for the ozone loss.". In summary - you and the crackpot above take part of the usual scientific process, which is characterized by continuous refinement of models, out of context and construct a fundamental disagreement from it, which never existed in the first place. Basic propaganda tool.

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  12. Re:Some curious coincidences by ChrisMaple · · Score: 2

    The SO2 and trees are relevant because they are another article by the same person. While it is possible for some truth to be found in a forest of lies, it's not a good place to go looking for it.

    That said, there were a lot of errors made by those who proclaimed that acid rain was a serious problem. In addition, there was plenty of reason to reduce sulphur emissions beyond the fact that SO2 forms suphurous acid: SO2 is a poison by itself, as is H2S in sufficient concentration.

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  13. Re:can someone please explain a couple holes I see by riverat1 · · Score: 2

    The difference between the North Polar region and the South Polar region is that the Arctic is an ocean surrounded by land and covered by ice and Antarctica is land surrounded by ocean with ice sheets built up on it. It's considerably colder in Antarctica. The two regions are not really very comparable when you get into details. The Wikipedia article on ozone depletion has an explanation about the cause of the ozone hole. The northern hemisphere atmosphere and southern hemisphere atmosphere are somewhat separated but not completely which only affects how long it takes for full mixing to occur.

  14. Re:can someone please explain a couple holes I see by Mindcontrolled · · Score: 2

    That's where it gets somewhat complicated. While I have a pretty good grasp of the chemistry involved, I am a dilettante when it comes to atmospheric dynamics on the large scale. The stratospheric conditions over Antarctica seem to be particularly good for activating chlorine compounds into the catalytically active ClO-radicals. Cooling of the air in winter leads to sinking of the air masses which then, via the coriolis effect, form a very stable vortex that lasts into summer. This polar vortex isolates the antarctic stratosphere. Polar stratospheric clouds form and are confined to the antarctic region by the dynamics of this vortex. The particles in these clouds, water ice and nitric acid, help with the formation of active chlorine compounds. Due to confinement by the vortex, these compounds get not diluted out and lead to strong ozone depletion as soon as the sun comes up again. Over the arctic, this confinement effect is lower, so the clouds get "diluted out" - they only can form in the extreme cold, so less active chlorine is formed and the arctic effect is weaker. That's it in a nutshell.

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