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Antarctic Ozone Hole Leveling Off 353

Posted by Hemos
from the getting-smaller dept.
twistedfuck writes: "An Irish Time article reports that the size of the hole in the antartican ozone layer is levelling off and should begin reducing in size. It seems like it should be welcome news but it is tempered by the fact that more UV radiation will reach the southern hemisphere this year because the hole will persist longer. Unfortunately I can not find any details regarding the NOAA report on their website." Update: 11/06 17:31 GMT by H :Thanks to Isaac Lewis, NOAA Sysadmin and Slashdot reader, for pointing out more information, as well as pointing out the ozonelayer site.
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Antarctic Ozone Hole Leveling Off

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  • by bonzoesc (155812) <bkerley@@@brycekerley...net> on Tuesday November 06, 2001 @02:49AM (#2526487) Homepage
    Are we to believe that this reduction in size is a result of global regulation of CFCs, or could it possibly just be part of a natural cycle? Too bad we didn't get satellites before styrofoam.
    • Last summer I did some educational outreach for the lab I work for, at a day-camp for science kids, and the topic was ozone one day. If I remember correctly regulation can't possibly account for this, because the CFC's have a destructive lifetime in the atmosphere for something on the order of 100 years. ie. the little buggers break apart O-3 for a long time after we stop using them. Even if we stopped all CFC use today, we wouldn't see any atmospheric effect for many decades. Begging the question: why IS the hole reducing?
  • Antarctic (Score:3, Funny)

    by Rura Penthe (154319) on Tuesday November 06, 2001 @02:52AM (#2526494)
    Pleeease can you spell it right? :) I swear it isn't hard!
    • by PD (9577)
      I think you are mistaken. The citizens of the Antarctic prefer to be called Antarticanesians.
  • Size will decline? (Score:2, Interesting)

    by Man of E (531031)
    I don't know much about ozone and such, but why would the size of the hole start to decline? Are we producing additional ozone that could somehow refill the hole? Is the remainder of the ozone layer spreading out to fill the gap?
    Are there any meteorologists/ecologists out there who know how this works?
    • by dragons_flight (515217) on Tuesday November 06, 2001 @03:33AM (#2526569) Homepage
      Sunlight naturally converts some oxygen to ozone in the upper atmosphere. Problem is that when CFCs and other chemicals are present, they eat up ozone far faster than it is typically produced.

      Ozone is harder to produce and easier to break down when it is cold, which is one reason ozone is at its lowest levels over the poles in winter (also when there is a deficit of sunlight). The poles are also especially vulnerable because global wind patterns circle around them rather then refreshing the air. Even the most stubborn air pollutants will break down or become absorbed by the environment if we stop pumping them out and give the Earth time to get back to normal.
      • nice try, but it takes CFCs 50 years to get to the upper atmosphear where it can cause the damage to O3. after that the CFCs remain active for 50 more years. so lets see. the CFCs that were released around 1950 are just getting there, that means that the CFCs that were released the day befor the regulations were aprooved have 40 more uears to get there.....seems that the hole is not caused by the CFCs in the air......remember, a corolation does not equal causation, only that there is a relationship. ....perhaps we could not start to measure the atmosphear chemical levels before we began to produce CFCs. perhaps the hole had been growing for the last 400 years. but since our small scope of observation corrolated to the time that we could start measuring the chemicls in the atmosphear we drew a conclusion that was not scientific at all, instead we drew an emotional conclusion based on only part of the facts.
        • Okay, I don't know that the ozone hole is principally man-made, or all the potentially natural causes involved. I do know that if human CFCs are up there then they will be causing problems for ozone. Since chlorine and bromine act as catalysts for the break down of ozone, they don't need to be present in large amounts to have a large impact.

          An interesting question to ask though is where does that 40, 50, 60, 100 years number for travel time and pontency time of CFCs come from. Not surprisingly it comes from those opposed to controls on CFCs. What do people promoting those controls say? If they are honest, they typically say something along the lines of "we haven't the foggiest clue". Before the ozone hole no one really had any expereince with gas diffusion on this scale. And you are kidding yourself if you think anyone in either camp has a really good understanding of high level atmospheric chemistry, they don't. There are constant surprises.

          Similar but not directly related, the experience with the carbon cycle suggests that those the numbers for CFCs might be significantly high. Scientists want to know how fast carbon replenishes itself in the low atmosphere, or equivalently how long it takes before the majority of CO2 emitted today is returned to the biosphere. Prevailing theoretical wisdom pegged this number at around 20-30 years, but recent experimental evidence is giving a number more like 4 years. I could believe that the estimates on CFCs were similarly too large.

          Ultimately though, if CFCs can reach up that high then they will cause damage. Whether they are a primary (or even a significant) cause of depletion is hard to tell, but the ozone layer will probably be better off that we aren't using them. The issue of the ozone hole won't be resolved by people like us sitting on slashdot, it may be though by people who go out and see if the levels of pollutants in the upper Antartic atmosphere actually are dropping off.
          • hey, I think that we need to control all substances that can damage the earth, but lets not do it through miss information and FUD, lets tell people right out that the reduction in the hole may not be caused by our lower production of CFCs, but we should maintain those production levels because they are harmful. the time for fear was over after the legislation was passed, lts educate people and show them that there are other reasons to keep levels low.
          • Drat. As someone pointed out, I misspoke and somehow managed to reverse the issue of who was speaking for the long travel and life spans on CFCs.

            Those SUPPORTING CFC controls say that they are persistent in the environment and take years to reach the upper atmosphere. Those OPPOSED to controls or just plain NUETRAL, say that they don't know the time span involved.

            Don't know how I managed to get that backward when writing it down. Brain fart I guess. Sorry.
        • i>nice try, but it takes CFCs 50 years to get to the upper atmosphear where it can cause the damage to O3

          This is kind of sad. Read up on the details of the science involved in the ozone issue - it is _known_ beyond all reasonable doubt that the problem is manmade.

          Ozone hole science is NOT based on correlation.

          It sounds like you've misheard something along the lines of "CFC's can take as long as 50 years to reach the upper atmosphere" and turned it into some cosy argument for there being no need to change anything.

          You say "perhaps" this, "perhaps" that. But the fact is that most of these "unknowns" are not unknown at all. The doubts you raise have been laid to rest a long time ago by sound methodology. Nobel-winning methodology in one case. Just because joe-public-friendly articles don't have the space or readership go into hard, tedious, boring, ugly science doesn't mean the science isn't rock solid.

          Just because the science indicates that particular industrial emmissions are the cause doesn't mean that it must be some sort of wacko lefty greenie psuedo-science.
          • please show me the study that gave the data that showed the Ozone hole was non existant in 1940 but then in 1960 it was there. then show me the study that shows that a man made OZone hole will close up in 10 years.....sorry but you are corrolating agin sir.

            hey bob, I kicked the door and the light came on. this must be how you turn a light on.
        • nice try, but it takes CFCs 50 years to get to the upper atmosphear where it can cause the damage to O3.

          My guess is that what you read somewhere said, chemicals can take as long as 50 years to reach the ozone layer, but on balance they get there "It can take days or even years for some chemicals to reach the stratosphere." (this quoted from this article [enn.com] at ENN.)

          Also, not all CFCs take so long to break down. To quote the ENN article again, "Ozone depleting chemicals such as CFCs, halons and other substances commonly found in coolants, foaming agents, fire extinguishers and solvents linger in the atmosphere for different periods of time."

          perhaps the hole had been growing for the last 400 years.

          Actually, the hole did appear after we began measurements in Antarctica. This does not preclude some cyclical natural phenomenon, but there's good evidence that anthropogenic effects are at least a major part of the problem.

          Indeed, the evidence is much more clear than anthropogenic global warming.
      • The poles are also especially vulnerable because global wind patterns circle around them rather then refreshing the air.

        Then how do the pollutants get there? Walk there on their own? I agree that we should take care of the environment but some of this stuff is so concocted it not even funny. As in the idea that our pollutants are the major cause of the ozone depletion. While I think they may have some effect, I believe its more likely to be a naturally occuring cycle.
    • Here is the link:

      http://www.noaanews.noaa.gov/stories/s792.htm [noaa.gov]

      lots of links and pretty pictures available.

      (And just a note: Radio Free Nation had this back in the middle of October, but what do I know? [smile])

  • Mother Nature (Score:4, Interesting)

    by rockwood (141675) on Tuesday November 06, 2001 @03:00AM (#2526509) Homepage Journal
    IMHO Mother Nature takes care of herself. Fires to clean the earth, wind to sweep away the garbage, seasons to refresh the vibrance of life and so forth...

    This article suggests that though the total mass of the hole is reducing in size, it is also maintaining itself for longer periods. Without research, an immediate assumption would suggest that this would be letting the same doses of UV rays reach the earth annually.

    I'd say Mother Nature is attemtping to counteract our efforts and regulate the earth the way she has done for millions of years!

    And given our (human) track record.. I'd give 1000:1 odds in favor of Mother Nature doing the right thing.
    • by NecroPuppy (222648) on Tuesday November 06, 2001 @04:20AM (#2526645) Homepage
      *sigh*

      The increase of UV radition getting to the earth due to the depletion of ozone is smaller than the error factor of the best detection instraments.

      And, even if it weren't, even changes as high as 20% aren't abnormal in nature. Otherwise, there wouldn't be life in Florida...
      • And, even if it weren't, even changes as high as 20% aren't abnormal in nature. Otherwise, there wouldn't be life in Florida...


        Explain about the life in Florida bit?

        • The difference between the UV level in some parts of Florida and other parts of the US is as much as 20%.

          So, if people in Montana, for example, were worried about UV, they could look at Florida and realize that it isn't that bad.

          Well, except for Epcot.
      • Yes, please explain this O Brother of Mine.

        I believe that you are once again operating with incorrect scientific information. But I would still like to hear this explained.

        EFGearman
        • Ahh, someone let the idiots loose on Slashdot again...

          In the April 15, 1993 issue of the Washington Post, John Fredrick, an atmospheric physicist from U. Chicago, was quoted as saying, in reference to UV light, that,

          "The amount of increase that the theory says we could be getting from ozone depletion is smaller that the error of our best measuring instraments.


          If an increase of 20 percent were going to be so damaging, there should be no life in Florida..."
  • Big Deal... (Score:4, Funny)

    by Anonymous Coward on Tuesday November 06, 2001 @03:02AM (#2526511)
    Who Cares? This only affects those of us that
    actually go outside, and in all honestly, how many of us have actually been outside in the
    past two weeks. (Outdoor-type quake mods do not count)

    mccann@telalink.net
  • by cats-paw (34890) on Tuesday November 06, 2001 @03:03AM (#2526515) Homepage
    I was just looking into this not too long ago. Strangely enough, we met someone from Israel while we were travelling in New Zealand who said it had closed, which I was sure was wrong. Turns out it's still there.

    And remember it's not really a hole, i.e. there is ozone present, it's just at significantly lower levels.

    Here are a couple of sites I found useful :

    www.epa.gov/ozone/science/hole/holehome.html
    www.atm.ch.cam.ac.uk/tour/

    When we were in New Zealand the sun feels different ! It feels very intense and somewhat uncomfortable, and it was only the first month of spring. You HAVE to use sunscreen.
    • Speaking as a New Zealander. The Sun and Heat here are probably unlike anything most people have felt. Burn time in the summer comes down as low as 10 minutes. You can't even get in your car and go for a drive without getting burnt. In mid summer you literally have to put on a top with long sleeves or your arms will physically hurt if you are out in the sun
    • Actually, I think that was more due to the fact that you were thinking autumn with shorter days than spring. When I lived in NZ in 97/98 (south end of the Mainland) I found no difference.
  • by Moridineas (213502) on Tuesday November 06, 2001 @03:13AM (#2526529) Journal
    The problem with environmental theories is that they are just that...theories.

    Much like chemistry of 50 or 100 years ago in many ways would seem laughable to what we know now (and will again in 50 years probably), the science of the environment is a young and new science. Unlike chemistry or physics, it's much harder to do experiments, and the timescales involved are immense.

    The truth is we simply know too little about the Earth to make longterm models and whatnot that are dead on. We can make GUESSES, and maybe even good guesses, but there is still so much that we don't know at this point.

    As a side note-it is my understanding that CO2 levels during the time of the dinosaurs were much higher than they are today. The Earth can handle huge changes with relatively little environmental impact. It's been around (what? 5 billion years?) a long time, I don't think humanity can destroy it in a little over two century.

    Scott
    • by mrwilsox (174578) on Tuesday November 06, 2001 @03:31AM (#2526566)
      You're right, we're not going to destroy the earth in a little over two centuries. However, we are making great strides toward making the earth very, very hard to inhabit for humans (and a number of other critters). If we just let things keep on going as they are and use up all of our fossil fuels and spew pollution into the air, land, and sea, the earth won't be a great place to live for us. But you better believe Mother Nature wouldn't care one bit if humans disappeared forever. Earth itself would keep on living, with other species remaining and probably a lot happier that we're gone.
    • It's been around (what? 5 billion years?) a long time, I don't think humanity can destroy it in a little over two century.

      It has actually been around about 4.6 billion years (age of the oldest rocks [usgs.gov]).

      As other folks pointed out, we humans can't (yet? ever?) destroy the earth, but we can certainly make it unable to support our form of life [thinkquest.org].

      One last thing: "theories" are generally accepted by the scientific community until they are disproven. The semantics of the word does not lessen the idea behind it. The "theory of plate techtonics" is just that: a theory -- but some plates keep subducting and causing active vulcanism nonetheless.

    • by CaptainCarrot (84625) on Tuesday November 06, 2001 @04:44AM (#2526683)
      As a side note-it is my understanding that CO2 levels during the time of the dinosaurs were much higher than they are today. The Earth can handle huge changes with relatively little environmental impact.

      Actually, the environment at the time of the dinosaurs was hugely different. Earth had no polar ice caps, and the continents were arranged differently. In the dinosarus' heyday around the middle of the Jurassic, the Atlantic Ocean didn't exist. The bulk of the land was grouped into an enormous crescent surrounding what is now the Indian Ocean. The coasts were warm and humid; the continental interior was desert. It was a world utterly unlike that we live in today, and we probably could not have flourished in it.

    • by Jormundgard (260749) on Tuesday November 06, 2001 @04:48AM (#2526689)
      Environmental science is over 100 years old, but it didn't start to thrive until after WWII.

      The ozone hole and CFC sitatuion is one of the most well understood things in science however. It's due to the following:

      • Companies used to produce CFCs - a combination of Chlorine, Fluorine, and stuff that is extremely resilient. Most importantly, it's resilient to radiation, so it can survive long distances. Note that some people try to compare this to the chlorine dumped by Mt. St. Helens - but free chlorine is easily busted apart by radiation, while CFCs can survive the trip ahead of it.
      • The Equatorial Winds are a series of currents that blow from the equator to the poles (with a slight lean towards the north(?) ) - these blow chemicals form the equator (where humans mainly live) to the poles. Chlorine molecules are destroyed in the upper atmosphere by radiation, but CFC's survive the trip.
      • Finally, at the poles, the CFCs (which take a while to decay) break up in appreciable amounts at the poles, where the free chlorine reacts with the ozone, and breaking it apart. The fact that there are free fluorine atoms in the poles, which is only possible by man-made actions, is the smoking gun.

      • Based on the equatorial cycle, one would expect to be free of CFC effects after about 100 years - I guess it's been about 25? So I guess this is about when one would start to notice the effects.

        Although there are the occasional puppets who still denounce ozone problems, the industries and governments were immediately convinced by the evidence, which is why humans have probably fought off this problem.

        Finally, the CO2 issue is a global warming thing, which isn't really related to the ozone hole problem. That's a polar icecap melting problem, and the data is still not totally convincing---the problem is that some predictions say that it's too late to prevent a 1m rise in sea level.
      • I'll just point out a slight inaccuracy in your highly informative answer. CO2 increase in the atmosphere does directly relate to the ozone hole problem. CO2 increase causes global warming. Global warming causes the (presently) weak polar vortex in the North Pole to strengthen. Strengthening of that polar vortex causes the ozone hole in the northern hemisphere to increase in size. Well, many more people live in the land around in the higher latitudes of the Northern Hemisphere...

        That's the thing with the environment; everything is interconnected.

    • The problem with environmental theories is that they are just that...theories.

      Funny, that's exactly what creationists say about evolution. To quote Stephen J. Gould:

      In the American vernacular, "theory" often means "imperfect fact" - part of a hierarchy of confidence running downhill from fact to theory to hypothesis to guess. Thus the power of the creationist argument: evolution is "only" a theory and intense debate now rages about many aspects of the theory. If evolution is worse than a fact, and scientists can't even make up their minds about the theory, then what confidence can we have in it? Indeed, President Reagan echoed this argument before an evangelical group in Dallas when he said (in what I devoutly hope was campaign rhetoric): "Well, it is a theory. It is a scientific theory only, and it has in recent years been challenged in the world of science - that is, not believed in the scientific community to be as infallible as it once was."

      Well evolution is a theory. It is also a fact. And facts and theories are different things, not rungs in a hierarchy of increasing certainty. Facts are the world's data. Theories are structures of ideas that explain and interpret facts. Facts don't go away when scientists debate rival theories to explain them. Einstein's theory of gravitation replaced Newton's in this century, but apples didn't suspend themselves in midair, pending the outcome.

      The problem has nothing to do with the "theoryness" of environmental science, it has to do with the relative dearth of data with which to develop theories. In any case, as far as practical approaches, erring on the side of caution would be a prudent one. No factories are going broke because they had to install scrubbers in their smokestacks, just as loggers weren't losing their jobs because of the spotted owl. The picture of onerous environmental regulations as an unbearable crippling burden is a smokescreen thrown up by industry.

    • Other people have said important things about about differences in the world in the age of the dinosaurs and how you can't destroy the earth but you might make it hard to live on, but I want to add one more.

      The highest known levels of CO2, in fact a jump to around 10 times the modern value (IIRC) occurred prior to the age of dinosaurs and is correlated with the extinction of 90% of all species alive at that time. Of course it's not neccesarily causal and might just be a side-effect of whatever killed all those species, but I would be very leary of supporting arbitrary changes in CO2.

      A little CO2 increase might have a net positive impact, but I would certainly want to take it slow and not be uncontrolled. Besides I'm not sure I want to live in a world like the one the dinosaurs lived in.
  • by Jingle Returno (531353) <AltecFinancial@SertyUnifiedFront.org> on Tuesday November 06, 2001 @03:15AM (#2526532) Homepage
    Thus, the issue of whether the global ozone layer shows a steadily depleting trend is still controversial.

    Taken right from the essay. Although I would agree with you in that I'm not totally convinced on the issue of 'ozone layer depletion' either, it is interesting to see that this article begins with a scientific basis of 'the uncertainty' of research on ozone layer cause and effect and quickly progresses to the fact that it costs lots of money to phase out 'potential' ozone depleting chemicals and whether or not it is in the US's interest to stay in potentially expensive environmental pacts.

    I think one of the key things that we have come to realize at the end of this century is that many of the large scale phenomena we witness here on Earth are the products of an extremely complex and often non-linear series of events. Our technology has reached the point where it can and often does cause serious changes to our environment. One of the problems with the point of view that this essay takes is that it neglects 'precaution' in favour of the idea that we should be more concerned with short term economical gain.

    If something has the potential to possibly cause damage, isn't it more logical to stop using it? Even if we are only right 1 in 10 times on whether something can cause damage to the environment, I would rather waste the money controlling the nine than sweeping the one under the rug.
  • by veddermatic (143964) on Tuesday November 06, 2001 @03:20AM (#2526544) Homepage
    "See, fuck the environment, it just fixes itself! That Alaskan Wildlife thingie my dad and Uncle Cheney say I should let thier companies drill in will be all wildlifey again in no time!"


    Oh well. Luckily the world will end AFTER I'm dead.

  • Press Release (Score:5, Informative)

    by ukryule (186826) <.slashdot. .at. .yule.org.> on Tuesday November 06, 2001 @03:27AM (#2526559) Homepage
    is at http://www.publicaffairs.noaa.gov/releases2001/oct 01/noaa01104.html [noaa.gov].

    To summarise the findings, it seems the density of Chlorine from CFCs has peaked, and it is expected the Ozone hole will gradually (i.e. over the next 50 years!) disappear.

    It now seems to be an interesting case of us screwing up our environment, working out what we'd done, and fixing it. However, you could consider that we just 'got lucky':
    • The fact that it was concentrated in one spot meant that the problem was identified before we'd managed to strip the whole atmosphere of ozone.
    • It was concentrated over the least populated part of the globe. Compare the increase in awareness/incidence of skin cancer in Australia/New Zealand with what might have happened if it was concentrated around the equator.
    • The solution (banning CFCs) had relatively little economic impact making it easily implementable. It was also a universally accepted solution.

    Compare this with the current situation re global warming, and this looks less like a successful victory and more like a warning shot across the bows ...
    • Strange (Score:3, Interesting)

      by socceroo (202491)
      I live in Melbourne. If you look at the piccies of the hole, you'll see it nowhere near approaches Melbourne.

      I have to use sunscreen when I go outside. I've got fair complexion and I burn up in the sun. Yet when I visit Sydney, I can spend 2 hours in the sun without as much getting a lick from sunburn.

      You have to wonder what the situation is like in Hobart or Antartica.
    • Re:Press Release (Score:3, Insightful)

      by Anonymous Coward

      I would like to make two counter-points:

      1. If the hole HAD been over the equator (I know, it couldn't have been), you can bet there would have been a lot more pressure to do something, and quick. It would have brought home to the world how much damage we can do to ourselves through capricious pollution. Millions of third-world people affected with a deadly, lingering, and expensive-to-treat disease would have been a rude awakening. Then again, HIV in Africa is effectively ignored by the media, so maybe I'm wrong on this one.

      2. There wasn't a lot of support for banning CFCs early on in the campaign. Prince Charles was mocked for his stand against them. The same people who claim that deforestation/carbon output/industrial pollution is no big problem now claimed that all this anti-CFC stuff was nonsense, bad science, and hippy-talk. It took actual observations of the hole by Antarctic researchers, solid backing by environmental scientists, and popular support before things got changed.

      I don't think things have changed much, so I don't take this news as any sign that we've changed our thinking. Too many people have an interest in making a quick buck at the expense of future quality of life on this planet.

    • Re:Press Release (Score:2, Interesting)

      by buglord (455997)

      I read a nice article (not sure if was on slashdot), that banning chlorine will be more damagin in the long run.

      Because chlorine is an industrial by-product of many different chemical processes, it has to get gotten rid of somehow. Thus chlorine gas in warfare, cfc's in spray cans, pvc plastics - it's cheap!

      So now the chlorine has to get bound in other materials and will pose an environmental threat some hundreds pf years later.

      Maybe we should take a look at the processes having chlorine as a waste product and try and do them more environmentally-friendly
  • by Powercntrl (458442) on Tuesday November 06, 2001 @03:29AM (#2526561)
    Back in '92 (I believe - not sure), most new air conditioners started being manufactured with CFC-free refrigerants. The "new" coolant requires different tolerances in the compressor and evaporator systems. What this means (as anyone who has tried to retrofit an older car air conditioner with CFC-free coolant can tell you) is that the new coolant doesn't work as well in older systems. This has actually created a black market for the older coolant (freon, as I recall) from countries where it is still manufactured.

    If this research is correct, the coolant switchover and strict rules regarding the recovery of waste freon have probably played a part in the improvement. Even if this is an inconvience for auto A/C mechanics, it's a small price to pay to preserve our valuable ecosystem.

    So if you're driving an older car and your recharged air conditioner doesn't seem as cold as you remember it, you're right. But you're helping save the enviorment.

  • More info on the same subject [nasa.gov].

    Every time I hear someone talk about the ozone hole that we (humans) are creating, I have a little laugh to myself. I mean, seriously... Human beings populate such an insanely small percentage of the Earth's surface (I mean, far less than half is even land anyway), how can you believe that we could really have such an immediate (read: 80 years) impact on something like the global climate? Come on, I think that's getting just a little bit of a big head... We wish we could control the weather...

    • Ahh, false humility.

      Sure, human beings populate only a small bit of the Earth's surface (and an even smaller portion of its volume). An atom bomb takes up very little space vis a vis the area it destroys, or a virii in the hosts they kill.

      You should take a look at a photo of Earth from space, at night. See all the glowing splotches? Those are human cities, pumping light into space. We know how to leave a mark.

      Oh, sure, we can't "control" the weather. That doesn't mean we don't influence it. It takes a lot less skill to wreck a car than to drive it well.
  • Lewis Black (Score:2, Funny)

    by QuiK_ChaoS (190208)
    In the great words of Lewis Black:

    "We've got rockets, we've got plastic wrap... Fix it!"
  • by ukryule (186826) <.slashdot. .at. .yule.org.> on Tuesday November 06, 2001 @04:27AM (#2526657) Homepage
    A good description of the process which results in the ozone hole can be found here [cam.ac.uk].

    Basically, the intense cold of an antarctic winter creates a vortex which isolates the air over the south pole, and allows build up of the CFCs. When the summer comes, the Chlorine from the CFCs acts as a catalyst to destroy the ozone.

    It now seems to be well understood - but it's one of those things that nobody could have predicted before it happened.
  • by sconeu (64226) on Tuesday November 06, 2001 @04:30AM (#2526660) Homepage Journal
    I thought that weather patterns tend to not cross the equator...

    If that's true (and even if it's not), why is the ozone hole over the ANTARCTIC? Aren't most of the CFC/ozone-eating gases being emitted in the NORTHERN HEMISPHERE? Why isn't there one over the arctic?
    • weather patterns may or may not cross the equator. I have no idea. but spreading weather patterns is something entirely different then dispersing a gas worldwide. The weather patterns are made of dynamic stuff like wind.

      //rdj
    • by Anonymous Coward
      Simple reason....

      Take a look at a map of the Arctic and the Antarctic, they are in fact almost exact opposites. The Arctic is a almost circular sea surrounded (almost) by land, roughly centred on the pole. The Antarctic is a high, near circular continent, roughly centred on the pole, surrounded by sea.

      The main effect of this difference is that the Antarctic geography allows a stable polar vortex, which isolates the Antarctic atmosphere during the polar winter, allowing the upper atmosphere in particular to become very cold. The nastiness in the Ozone equilibria happens during the spring when this extremely cold upper atmosphere is irradiated by the sun.

      The Arctic has a much weaker polar vortex, and hence, although ozone depletion is seen, it is much weaker.
  • ..but I thought I'd throw in my 2c (0.8c US) as someone living in New Zealand. Although the ozone hole does affect South Africa, where I moved to New Zealand from, the problem is definitely worse in the Land of Sheep(tm). The sun is more intense, even late in the afternoon, and I find that while the shade is a good indicator of the real air temperature, I get much hotter in the sun than I did in South Africa, despite the fact that air temperatures average around 5 C cooler.

    Just as a flame-worthy side note, there is a lot of antagonism in New Zealand towards the US because of Bush's decision to boycott the Kyoto(sp?) Protocol. The United States is demonstrably by far the worse offender with carbon dioxide emissions, and the general consenus in the scientific community is that these emissions are causing, or at least accelerating the hole in the ozone layer. To be honest, Usians aren't the most popular people (as a society, not individuals--I personally have met several and they were wonderful people), and this is just one more straw on the proverbial and cliched camel's back, with the United States saying what is effectively "Stuff you, we'll do what we want and who cares about your ozone hole causing rising skin cancer and medical costs".

    I didn't mean that as a flame, just a point of view. I'd rather you respond than just mod me down...I'm aware that I am oversimplifying it; this is merely the general trend of thinking in Kiwiland.

    • I doubt Bush will do anything. Personally, one of the first things I'd have done after the Sept. 11 attacks was sign a huge increase in alternative energy funding (Actually I'd have done it before that) with the goal of getting fusion working well in the next 20 years or so and also with the goal of every American driving a hydrogen powered vehicle by 2015. Would have killed several birds with one stone. Mandatory emission standards have resulted in much cleaner cities here, though, and to get a feel for that all you have to do is visit someplace like Romania, where despite the far fewer number of vehicles on the road, it's still fucking hard to breathe the air. Most people don't seem to notice though, since everyone smokes. Outside you're sucking in diesel fumes and inside you're sucking in secondhand smoke.
      • Hydrogen vehicles are probably never going to happen. Even the best metal hyrdride storage has an energy density of under 1 kWh/kg whereas gasoline has 12.7 kWh/kg. Liquid H2 has a larger energy density per kg than gasoline, but takes up four times more volume for equal energy, not including cryogenic devices.

        There is some hope for gasoline powered fuel cells, but I wouldn't be too hopeful here.

        At the end of the day, oil is too concentrated and convenient to be ignored. And because the Middle East is where it is cheapest to produce oil from, they will always rule the global commodity price, and will influence the price of all energy products.
    • CO2 is responsible for global warming, not ozone depletion.

      CFCs (chlorofluorocarbons) and some other gases like halon(tm?) are responsible for the thinning ozone. Most of these gases have been banned under the Montreal protocol for some years now, but because they are largely inert they can rise far into the stratosphere (which takes them quite a few years) where they do their damage. What happens up there is that the suns intense UV rays break the CFC molecules up and the chlorine ends up binding with an oxygen atom from the ozone. The actual reaction is here [nas.edu]

      CO2, on the other hand, absorbs infrared radiation from the earth reradiated from sunlight and keeps the heat in the atmosphere. It basically acts like a big blanket. CO2 is what the Kyoto Protocol is trying to limit.
      • Disclaimer: since this is a blatantly off-topic post, I have already modded myself down (no +1 bonus). Hopefully this is an intelligent enough post that those nice cracked-out modders will find some more worthy flamebait or trolling.

        You're right, of course. I hadn't thought this through very thoroughly, which was why I was careful to state that it was the trend of thinking in New Zealand, rather than my own opinion. As with many things in New Zealand (GE food being a major one), the good old Green Party uses ignorance and fud to spread misinformation, which turns into zealotry and close-mindedness much more easily than reasoned facts and rational evidence. It's amazing how many New Zealanders have nearly no conception of the real facts and information behind the issues they hold such vehement opinions on, and how they don't even question the emotive positions they take from those who should know better. Not that this is a New Zealand-specific thing; as long as humans are human this will continue to be the case.

        Every time I see mass demonstrations against GE food I wish that the media would actually inform people on the issue instead of simply commentating on the opinions that different parties hold. I guess that's one reason I'm studying journalism next year...

        Completely off-topic, I know. Sorry.

        Getting back (vaguely) to ozone holes etc, another poster mentioned the need for alternate energy sources. I figured I'd reply in this post; basically I couldn't agree more. It would make a decent difference to the global warming problem (at least if we believe the majority of the scientists involved in the study thereof), it would probably make some impact on the ozone hole problem (although this seems to be improving, probably due to such things as the Montreal Protocol), it would wean Usia off oil long before shortage became a problem (and this would probably quickly expand to the rest of the first world), and it would also ensure that premature shortage due to tensions in the Middle East wouldn't cause as much damage as is potentially possible. It would probably also lead to a number of offshoot technological and scientific advances that may otherwise not happen for many years yet.

        Frankly (and once again completely ot), I think there's basically only one thing in Bush's little brain. Money. And unfortunately, he's not smart enough to think long-term money either. Oh, and anyone wanting to flame me for "flaming" Bush...just think of all the speeches he has muffed. One of the speeches he made directly after the 11.09 attacks left me cringing as he completely screwed up a relatively common English word, then did it again, then corrected himself, and then did it again. Not the mark of a superior intellect to me.

        The problem is, if the US doesn't lead the world in the adoption of alternate energy, cleaner-burning fuels etc, who will? Other countries still make the attempt, but the US is the world's most powerful economy by far. We need them if this is going to work.

    • Just as a flame-worthy side note, there is a lot of antagonism in New Zealand towards the US because of Bush's decision to boycott the Kyoto(sp?) Protocol.

      Yes well. There's a fair amount of antagonism to Bush about it up here, too, especially from those of us who (a) didn't vote for him, and (b) don't think he actually won the election. I personally make a great effort to "live green" even if it involves some personal sacrifice (spending more $$ to buy environment-friendly products, etc) and I wish our semi-elected leadership was willing to do the same.

      You're absolutely right, it's a damn shame Bush is telling everybody else to shove off about Kyoto. I only hope the rest of the world is strong enough to say "screw you!" right back at him and keep on implementing the treaty. I firmly believe you guys are doing the right thing, and I know many other Americans do too...

      • Just a quick question:

        If you, as an individual can make an effort to live "green", which I must say is a nice effort to be making, than why can't we all?

        If we can all do that, why do we need government to force us?

        More than anything, government can regulate industry and keep them from destroying the world. But more than anything, as individuals, we must do our part. I am very tired of seeing "greens" who drive a nice lovely Ford truck on the way from the suburbs to work everyday, and then complain about the cost of filling up!

        More than anything, if environmental change is going to occur, individuals must change their lifestyle. All the government is useless if not for the actions of the people.
      • Last I checked, Bush obtained a majority of the votes in the Electoral College; hence, he won the election. Furthermore, the recounts in Florida by the news outlets down there have (last I saw) shown rather conclusively that his electors in Florida won a plurality of votes, contrary to the claims of the Gore-Lieberman campaign.

        Furthermore, on the issue of the Kyoto treaty, the Clinton-Gore administration had many years during which to push the Kyoto treaty through the Senate to ratification, and didn't even try. Perhaps you ought to direct some of your displeasure toward them instead of toward an administration that is doing exactly what it said it would do during the campaign?

    • there is a lot of antagonism in New Zealand towards the US because of Bush's decision to boycott the Kyoto(sp?) Protocol.

      Perhaps, then, you could convince the government of New Zealand to advocate a protocol treaty that, unlike Kyoto,

      • has an enforcement mechanism
      • doesn't exclude the vast majority of nations from its provisions
      • doesn't expect the US to pay an amount disproportionate to our environmental impact,
        and
      • deals comprehensively with the issue of global warming instead of dealing piecemeal with one emission at a time.


      Personally, while I am not convinced that the science has shown that there is or will be human induced global warming, I don't see that there is any long term negative impact from addressing what might be a huge problem. In the long run, even if there is no real danger of global warming, it would be to our economic benefit to have cleaner burning, more efficient vehicles, and lower emissions from power plants. I would love for there to be an international treaty that really makes an impact on pollution and emissions globally. But the Kyoto treaty is not going to have any real environmental impact long term, will cost an incredible amount in terms of cash and jobs up front, is not enforceable, is not manageable, is not extensible, and is really nothing more than a feel good measure for politicians to wave in front of their populations to say "see, we're doing something". I'm glad the US backed out without ratifying the treaty; I hope that by staying out, we force a reevaluation of the initial goals of Kyoto, and that we eventually end up with a comprehensive treaty that results in a cleaner environment for the future. But Kyoto is fundamentally broken and is certainly not the way to get there

  • I've heard there have been some, um, anomalies in the flocks. Are they growing wool again? How about the lamb-meat? Is it still tender and juicy from the prolonged basting? :-)
  • Great (Score:2, Insightful)

    by andy_from_nc (472347)
    You know those fine men in Washington are going to use this as evidence that there is no need for tougher environmental laws. Not that they'll understand the difference between global warming or the ozone hole or what have you.

    Can someone find this study and maybe post a link? Have there been any reports of corrolation between the reduction in the use of CFCs in many countries and the leveling off of the hole or was it a natural phenomenom after all.

    To the guy in NZ who talked about the anamosity toward the US for backing out of the Kyoto treaty. We're all feeling very patriotic, but you please remember a majority of the folks in this country did NOT vote for Bush and co. We voted for a guy who thought (according to his book) Florida would be under water in a few years if we didn't do something about the environment! Didn't like either of them, but I vote a bit on the enviromental side with a strong streak of anti-relgious fundementalism. I think pulling out of the Kyoto treaty even if you DIDN'T agree with its premise was a mistake because it dishonored our country. We played a big part in setting the thing up then canceled at the last minute. For that I am truely sorry.

    Unfortunately, due to recent events it will be a number of years before we'll pay a great deal of attention to the environmental problem. It may be a number of year before we link the gas prices with all of us buying SUV's that get 8 miles a gallon (not me!), but we will..hopefully before we melt the place.

    -Andy
    • You can't blame the goverment for this problem. I'm not going to get into the whole Bush vs. Gore issue, its over and what's done is done and complaining isn't going to change it- That said even if Gore were the president it wouldn't change a thing, people here still wouldn't care. We'd still be buying SUV's, they would still eat tons of fast food and throw the trash in a landfill, people still wouldn't be recycling anything.

      All the regulations in the world aren't going to change people's attitudes, people's attitudes will change when American's stop being the greedy jerks that they are (and I'm an american so it isn't flamebait).

      I agree with you but more government isn't the problem. Bush wants to drill in Alaska because we demand cheap oil. (and its a better solution that getting it from Sadaam). If Gore had been elected and did everything with the environment that he said he would do... he would be out in 4 years. Not to say that Bush won't be (although with our little war he stands a chance) but Gore wouldn't have stood up and done the stuff he promised, he would give in under the presure - just like everyone else....

      Okay enough rant.
  • by LazyDawg (519783) <lazydawg@nOsPaM.hotmail.com> on Tuesday November 06, 2001 @08:43AM (#2526979) Homepage
    Ok, here's the deal:

    Stratospheric ozone is created by bombarding normal, happily breathable O2 mollecules with ultraviolet light, splitting the O2 into a pair of O1's. These O1's eventually bump into another O2 mollecule and create O3. Big woop.

    Where there is solar UV light, you'll probably see some ozone popping up. Since the Antarctic Desert is in the dark for a good chunk of the year, you'll discover a not-too-surprising lack in stratospheric ozone over winter and well into the Spring. Also not surprisingly, we have an ozone hole over the north pole.

    Over the north pole, of course, there isn't quite as extreme a desert as over the south, and there are more large land masses nearby to carry air better.

    Back in the 30s when the first weather measurements were taken in Antarctica they found almost identical levels of UV light hitting them as during a modern winter. Greenies prefer to depend on climactic models rather than empirical evidence these days, however, so their multi-million dollar research is stating the problem is getting bigger, even if someone else's multi-thousand dollar research is saying the opposite.

    The ozone hole is the result of too many people putting faith in government, who can't predict the future more than a few weeks down the road, and weather men, who can't predict the future more than a few days down the road, and expecting their government-funded computer models to be able to predict the future years down the road.
    • Good point (Score:4, Insightful)

      by Uttles (324447) <uttles@[ ]il.com ['gma' in gap]> on Tuesday November 06, 2001 @09:17AM (#2527022) Homepage Journal
      I agree with your statements, and I've read similar articles in scientific periodicles. Those articles, however, are usually well hidden and no longer than half a page, because they aren't very popular. So why is rational thought about the O-zone not popular? Well it's not sensationalist, it doesn't give people something to "fight" for, and people who are "environmentally concious" just hate to admit that they are wrong.

      Another thing that I don't think you touched on, our climate goes in cycles. I don't recall the exact dates, but I know that some time ago in recent history (1960's maybe?) all of the popular scientists were warning of global cooling. That's right, the earth was getting too cold and there was going to be another ice age if people didn't do something about it. Our climate is not as stable as some would imagine, and contrary to popular beleive we humans have nothing to do with it. Yes, in large cities there is smog, but that is a microclimate just around the city, and it dissipates in the atmosphere and goes away eventually, doesn't affect the global environment. The global climate is something that is very dynamic and not easily understandable. One thing is for certain though: there is no proof that we have a problem with the O-zone layer.
    • It should also be pointed out that at the poles the atmosphere is at a tangential angle to the sun whose radiation creates the ozone. You are never going to get alot of ozone with the sun comming into the atmosphere at that angle, the UV light would half to travel thru dozens of times more atmosphere than at the equator.

      The real questions we should be asking are ones like why did NASA propose and get a multi-million dollar satelite to study ozone deplletion, when they know darn well that this is normal. Why did freeon become illegal the day after DOW-chemical's patent ran out (DOW also has a patnet on the only known replacement that hasn't expired yet!) These are the real reasons why the ozone is a big deal. Freeon is a very heavy gas, the dispertion probability of it getting up into the upper atmosphere is almost non-existent.
  • I work for the Climate Monitoring and Diagnostics Laboratory which is part of NOAA (National Oceanic and Atmospheric Administration). If anyone is interested, our lab launches balloons that help measure the level of ozone in the atmosphere at the South Pole.

    More information can be found at the South Pole Ozone Page [noaa.gov].

    Eric
  • The ozone hole was discovered back in 1958 by the British Antarctic Survey. At the time, they saw it as a natural phenomenon caused by the South Atlantic Vortex -- a well established air movement pattern.

    Now, there may be some real science behind CFCs and ozone depletion. The original lab work that demonstrated the chemistry was real. However, most of the material that comes my way about CFCs in the atmosphere seems more like spin than science. Maybe someone here can point us to some more measured and competent publications than I have been able to find.

    Before we jump to too many conclusions about all the anti-CFC material, we should bear in mind it is standard practice for corporations to seek methods for making obsolete materials for which the patents have expired. Some creative lobbying and legislation is a great way to stop third-world companies turning out your products on the cheap.
  • For ozone to be destroyed you need:

    1. UV-Light
    2. CFCs and Ozone
    3. cat nitrogen > /dev/null

    Although I am sure that other chemicals can break down ozone, CFCS are the most common and best at doing it because they are lighter than air and they normally DO NOT react with anything around us (at or near sea level). These two properties make them fly up high into the ozone layer. The non-reactant portion is what made these chemicals so great and so unthought of as causing problems. To destroy ozone molecules you have to have some very specific conditions:

    1. Uv-light forces the reaction breaks molecules down and what not
    2. chlorine, as in Chloro-Flouro-Carbon (CFC), these kill ozone
    3. no nitrogen, this is because nitrogen stops the process, being a noble gas it doesn't react too much

      Okay so now how do you get these conditions, and why is there no northern ozone hole? Well we have uv-light and aplenty so that's not a problem. The first issue is gathering a lot of CFCs (and ozone) into one place, this is taken care of by the Antarctic vortex. The vortex is there during certain months of the year and it builds up a lot CFCs and Ozone into a small space. In the northern polar regions it isn't so prominent because there are landmarks to break up these winds, however there are some weaker ones that are present in the north. Okay, we got ozone and CFC and light, now we need to get rid of the nitrogen. This is handled by formation of nitrogen clouds, which are clouds that are really cold and really high up that contain droplets of condensed nitrogen, and now the nitrogen is gone in the atmosphere and CFC havoc may occur. This doesn't happen in the north because the north pole is much warmer (or at least enough to prevent this). Now the scary thing is if we get a cold winter in the north then a big hole can form in the north, and if you look at a globe there are millions upons millions more people in the upper northen latitudes than there are in the southernmost latitudes. And if you use the following statistic, -1% ozone layer = +2% UV-light on the surface of the Earth = +4% skin cancer, which is sorta bad when applied to cities like London and Quebec and what not (yes these ozone holes can affect huge areas).

      Now before someone tries to beat me down for using pseudo science, my mother is on the DIAL team which is a NASA group that measures the ozone hole using a LIDAR(Laser detection) system. These were the people who went to confirm the ozone hole when NASA originally thought the TOMS satellite was malfunctioning because it had almost no readings in the south pole for ozone. I may have bungled some of the facts so if I did please correct me. I think most of these chemical processes have been tested in a lab so they are empirical evidence.

      As for the the stabilizing of the ozone I can only make a few conjectures: 1) the most likely IMHO, the temperature in the southern pole haven't been as cold lately, I know I have been going through some wacky yearly climate cahnges here, 2)the Earth is mucuh more resilient than we like to think, or 3) We're missing something that is there and it may not be only the CFCs or it could be a natural cyclical event, but I have trouble believing it is natural with all the scientific evidence I have seen. There are still too many CFCs in the ozone layer for it start repairing, and due to the resilience and the near-non-reactance of CFCs they will be around for another 60-100 years, before the ozone makes a come back and another 100 after that to repair itself.

    • Small correction: Nitrogen is not a noble gas. N2 is not reactive (hence, we have a nice, non-reactive atmosphere that doesn't chemically decompose us), because it is tightly bound. Atomic nitrogen, however, is highly reactive (that's why N2 is bound so tightly, and why most chemical explosives are nitrogen compounds). Nitrogen interrupts the CFC cycle because, when N2 is photo-dissociated into atmomic N, if the atomic N interacts with a CFC molecule, the molecule is broken up. CFCs live so long in the upper atmosphere because solar emissions contain relatively little radiation with sufficient energy to cause the photo-dissociation of nitrogen. Of course, it's been a while since I did any chemistry, so I may have something wrong here.

  • Observations have just finished one 22-year solar activity cycle. Solar activity has been at a peak this year (producing magnificant aurora visible across much of the USA last weekend). This ascpect of natural causes should be understood too.
  • I've seen too many examples of people overinterpreting there data decrying "disaster is at hand" or "no way the environemnt could be hurt". So little is known about natural activity, that the scientists shouldn't over do it.
  • Here's some statistics and information on the ozone hole from the Climate Prediction Center:

    http://www.cpc.ncep.noaa.gov/products/stratosphere /sbuv2to/ozone_hole.html [noaa.gov]
  • NOAA ozone site (Score:3, Insightful)

    by Isaac-Lew (623) <isaaclew AT gmail DOT com> on Tuesday November 06, 2001 @12:41PM (#2527745)
    As some of you may or may not know, I am the system administrator for www.noaa.gov [noaa.gov] (the webserver, not the whole organization). Ozone information can be found on:


    [noaa.gov]
    http://www.ozonelayer.noaa.gov


    BTW - for anyone that cares, the ozonelayer site runs on a Linux box :).

  • Environmentalism. (Score:3, Flamebait)

    by mad_clown (207335) on Tuesday November 06, 2001 @07:12PM (#2530299)
    Rabid environmentalism cracks me up. It's one thing to reduce pollution to make the sky look less brown, or to reduce respiratory diseases and such, but all this "Save the Earth!" crap is such a lie. It's all about saving HUMANS, not the Earth. If we launched 600 high-powered thermonuclear warheads, life on Earth (on the surface at least) would probably be wiped out, or close to it. But don't forget that there's life TEEMING in the oceans, in pitch black, on thermal vents on the ocean floor that are far more inhospitable than we can make things on the surface. The Earth can take care of itself. It's made it to this point from being a molten ball of rock. No matter what harm we do, give our planet a couple million years, and it'll be back to normal... for instance, check out the surface of the planet... do you see many impact craters? No. Why? Because the Earth, unlike, say, Mercury or our moon, experiences alot of volcanic/weather activity that really helps to erase cataclysms. People ought to stop pretending that they're really trying to save the Earth and admit they're looking out for the species instead. This planet's been through alot more than humans, and once we're gone it'll continue to go on until the sun eventually envelops in when it grows into a red giant. Earth can take care of itself. It's people who need saving.

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