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Science

This Year's Ozone Hole Largest Ever 14

Katydid writes "Got sunscreen? It's UV exposure season in Antarctica again, and for the first time a city in South America - Punta Arenas, in Chile - was directly under the area of missing atmosphere we know and love. At 11.4 million square miles, the hole is 'more than three times the size of the United States.'"
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This Year's Ozone Hole Largest Ever

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  • We haven't always been able to measure ozone and have no way of knowing if this is the largest hole ever. It may be the largest we've observed, but I would question anyone who thinks it's the largest ozone hole *ever*.

    Just like the comet a couple years back that "just missed earth". I'm sure there are more that have come closer and missed, and we just weren't watching yet. (Yes, I know some have landed. But I would bet still bet that we are missed by more than we think.)

    Proud father,
    Jason
  • Fortunately, you can take a peek at this similar, but a bit more accurate story [bottomquark.com], posted over a week ago on Bottomquark [bottomquark.com].

    Hope you all enjoy!

    OldSaxon [mailto]


    You like science?

  • I think that one of the key things we have to come to realize at this dawn of a new century is the extreme danger of a growing and increasingly politicized use of science.

    Only dedicated and intelligent scientists, devoted to their field of inquiry [while in competition with each other] are qualified to make any determinations of provable risk, and if there is any at all.

    Increasingly science has become a pawn in the ideological culture wars of the modern real-politik, and claims are made when evidence is not yet forthcoming. If there was a 1/10 chance, then yes. But when the chance is unknown, that claim can not be made.

    An excellent, nay outstanding essay on precisely this can be found - at this location - [lawyernet.com].

    This article is slightly dated, but rings as true now as when it was first published.


    --
    man sig
  • Personally, I find it more dangerous that our society looks at the empirical evidence of science and calls it political when it threatens the cushy life that we've built for ourselves
    You have it completely backwards. It is the nonscientific and politically motivated elements of society that have called their statist motivated hysteria empirical. In this case, the scientific evidence clashes with the orthodox forces of the environmental left. This is not dissimilar from recent occurance with Corning silicone breast implants, in which an entire industry was driven virtually bankrupt by massive class action settlements brought about by a jingoisticly leftist media drum-beat of the horrid risks, representing itself as empirically justified... (when most scientists said their was insufficient evidence either way). And it turned out, after the fact, that there was no risk whatsoever for the diseases claimed. [Sure, it could be ugly if one ruptured, but that was all]. This came out after a successfull 3,000,000,000 settlement against Dow Corning. Now that significant studys have been done, it has been determined that there is no real disease risk whatsoever from silicon breast implants.
    Facts:

    1. The major public concern about a possible depletion of ozone comes from the fear that solar UV-B (280-320 nm) radiation reaching the surface will increase, typically by 10%. Yet UV-B intensity increases naturally by about 5000% between pole and equator; there is less ozone traversed when the sun is closer to the zenith. Hence a 10% increase at mid-latitudes translates into moving 60 miles (100 km) to the south, hardly a source for health concerns.

    2. The driving force behind the policy to phase out CFCs has always been the fear of skin cancer, particularly malignant melanoma. The EPA has predicted 3 million additional skin cancer deaths by the year 2075 as a result of ozone depletion. But unlike basal and squamous cell skin cancers, which are easily cured growths caused by long-term exposure to UV-B, melanoma does not show the same characteristic increase towards lower latitudes (38) (Surprisingly, European data on melanoma incidence show a reverse latitude effect).

    3. A breakthrough in our understanding of the mechanism of melanoma induction came with the experiments of Dr. Richard Setlow and colleagues at the Brookhaven National Laboratory. they conclude that 90%-95% of melanomas are caused by UV-A.

    4. But UV-A is not absorbed by ozone at all, and therefore melanoma rates would not be affected by changes in stratospheric ozone. This important finding undercuts one of the main reasons for the Montreal Protocol and all subsequent regulations.


    1. The question of global ozone depletion has been bedeviled by doubts about the quality of the data. Readings from Dobson ground observatories can be contaminated by long-term trends in SO2 pollution of the lower atmosphere.

    2. Another, quite separate problem is produced by the extreme noisiness of the ozone record. To establish the existence of a small, long-term trend it is necessary to eliminate the large natural variations, especially also those correlated with the 11-y sunspot cycle. This is an impossible task given the shortness of the record and the virtual absence of data on long-term variations of the solar far-UV radiation that produces ozone in the upper atmosphere. And then there is the huge cost, estimated at over $200 billion worldwide, of replacing capital equipment that cannot accept the substitutes, just for freon refregerant
    I myself have spent over $2500 on upgrading automotive airconditioners, for a system that is significantly less energy efficient , and therefore burns more gas to achive the same effect.
    I used to think the religious right was scary... now I've found the religious left to be far more pernicious. [Vote libertarian]

    --
    a truly functioning police state needs no police

  • The question of global ozone depletion has been bedeviled by doubts about the quality of the data. Readings from Dobson ground observatories can be contaminated by long-term trends in SO2 pollution of the lower atmosphere. DeMuer and DeBacker have demonstrated that the Dobson ozone meter can misinterpret the downward trend of SO2 pollution, giving rise to a "fictitious" ozone trend (1). (Their finding was confirmed by a task group, chaired by Robert T. Watson, in a Joint Workshop of the IPCC and the International Ozone Assessment Panel in May 1993).

    Another, quite separate problem is produced by the extreme noisiness of the ozone record. To establish the existence of a small, long-term trend it is necessary to eliminate the large natural variations, especially also those correlated with the 11-y sunspot cycle. This is an impossible task given the shortness of the record and the virtual absence of data on long-term variations of the solar far-UV radiation that produces ozone in the upper atmosphere. The analysis fails a simple test: The "trend" is found to depend strongly on the choice of time interval (2). An additional problem in identifying a man-made trend arises from long-term trends in sunspot number, and therefore long-term ozone trends of natural origin (3).
    1. DeMuer, D.; DeBacker, H. Revision of 20 years Dobson total ozone data at Uccle (Belgium): fictitious Dobson total ozone trends induced by sulfur dioxide trends. J. Geophys. Res. 97:5921-5937;
    2. Singer, S. F. What could be causing global ozone depletion? Schatten, K. H.; Arking, A. eds., Climate impact of solar variability. Washington, DC: NASA Publication 3086;
    3. Angell, J. K. On the relation between atmospheric ozone and sunspot number. J. Clim. 2:1404-1416; 1989.
  • A few years ago there was a hole in the ozone layer over the north pole.

    It was being bamed for all sorts of suff, including irrosion in the Yukon area of Canada.

    I have not heard anything about this for a little while, does any body know anything.....
  • Sorry, I was recalling an article some years ago that was an interview with one of the top guys on a committee to recommend a position to G. Bush on ozone - or something. I don't hav it, but it turns out I was WAY off on the timeline - Dobson did his study in the 50's. And now I find that the article I read was probably mis-stating the Dobson measurements. I just read a faq explaining : ----------------------------- Subject: 6.) But I heard that Dobson saw an ozone hole in 1956-58... This is a myth, arising from a misinterpretation of an out-of- context quotation from a review article by Dobson. In his historical account [Dobson 1968b], Dobson mentioned that when springtime ozone levels over Halley Bay were first measured, he was surprised to find that they were about 150 DU below corresponding levels (displaced by six months) in the Arctic. Springtime arctic ozone levels are very high, ~450 DU; in the Antarctic spring, however, Dobson's coworkers found ~320 DU, close to winter levels. This was the first observation of the _normal_, pre-1980 behavior of the Antarctic ozone layer: because of the tight polar vortex (see below) ozone levels remain low until late spring. In the Antarctic ozone hole, on the other hand, ozone levels _decrease_ from these already low values. What Dobson describes is essentially the _baseline_ from which the ozone hole is measured. [Dobson 1968b] [WMO 1989] .................................................. ............ So that's what I get for believing what I read - (and I won't necessarily make the same mistake with the above quoted FAQ either...) Sorry about spreading hearsay -
  • I remember reading about this nearly ten years ago, and what I remember is that the data often presented by the protagonists is carefully selected. As I recall, they choose to show trends in short periods - like ten years - that tend to support the scare. The reality is that due to the rotation of the earth, axis, jetstreams, etc. there will ALWAYS be an ozone hole of some size over the south pole (well, not the pole exactly, but...) The guy who invented the method of measuring the thickness of the ozone layer in 1930's took data in scatterred areas around the globe. His data showed a larger 'hole' than there is today (I thin this was in 1993) And - at least in 1993 - the method of measuring had not improved since the 30's, so it's not just bad initial data. BTW - it's really ony a thinness to the layer even today The other evidence often presented is anecdotal and mis-represented. The blind sheep often referred to at the tip of South America are supposed to be blind as the result of overexposure to UV. The truth is that they are isolated on an island and centuries of inbreeding have led to the blindness - not UV. (I wonder what that says about the farmers ?) I think the environmentalist groups latch on to issues like this (as well as the acid-rain issue) because it's a tangible, scary tool that facilitates the funding of legislative efforts. I wholeheartedly agree that we need to be much more responsible about pollution in general - especially water and air pollution, but these inflammatory issues are just lies being used to further a noble cause. They're doing the wrong thing as a means to a good end. We should have a society that is mature enough to do the right thing for the sake of it - not only in response to immediate danger. DaveL
  • "The guy who invented the method of measuring the thickness of the ozone layer in 1930's took data in scatterred areas around the globe. His data showed a larger 'hole' than there is today (I thin this was in 1993)"
    Actually, the hole in the ozone layer was discovered only in 1985. Do you have any references to back up your claim? Other than that, I agree with you that "We should have a society that is mature enough to do the right thing for the sake of it - not only in response to immediate danger". However, I don't think we live in such a society...
  • Hmmm... I find it interesting that you should cite Fred Singer, a notorious anti-environmentalist who has repeatedly received consulting fees from Exxon, Shell, Unocal, ARCO, and Sun Oil...
    (ref: http://www.sepp.org/bios/singer/cvsfs.html)
  • Skin cancer is the most popular association with depleted ozone, but there are other theoretical effects that could be much worse. The one that comes to mind is the destruction of microscopic ocean life close to the surface. The idea goes that these plankton and whatnot form the basis of a major food chain. Take out that link and the whole system could break down, starting with the oceans. Okay, I don't know the particulars and I'm not even sure I believe any of it, but the article sanemind offered didn't go very far towards convincing me that ozone depletion is not worth a great deal of economic upheaval. Besides, anytime anyone puts forth the economy as a good reason NOT to do something, I'm suspicious. --- You can find today's sig on page 28 of your User's Manual.
  • by Valdrax ( 32670 ) on Thursday October 19, 2000 @08:29AM (#703165)
    I think that one of the key things we have to come to realize at this dawn of a new century is the extreme danger of a growing and increasingly politicized use of science.

    Personally, I find it more dangerous that our society looks at the empirical evidence of science and calls it political when it threatens the cushy life that we've built for ourselves. In this case, the scientific evidence clashes with the orthodox forces of the industrial establishment. This is not dissimilar from the attitude of Big Tobacco with dueling studies over the cancer-causing effects of tobacco smoke.

    Facts:
    1. The ozone hole is getting larger. Satellite photos show this.
    2. The ozone layer protects us from the larger amounts of UV radiation outside the atomsphere.
    3. UV radiation contributes to cancer. FYI, UV radiation is sufficiently energetic to break carbon bonds -- the chemical backbone of all biological structures.
    4. Certain chemicals we emit into the environment react with ozone, disrupting the ozone-oxygen/free radical cycle that blocks UV rays.
    5. While there may be a natural component to this happening, deep cores taken from Antarctic ice indicate that this is the worst the planet has probably seen.


    Only dedicated and intelligent scientists, devoted to their field of inquiry [while in competition with each other] are qualified to make any determinations of provable risk, and if there is any at all.

    They are making predictions of risk, and they are starting to come true, but people are ignoring them, calling their research "political."
  • by sanemind ( 155251 ) on Monday October 16, 2000 @04:50AM (#703166) Homepage
    One thing that gets me is the near universal assumption that the 'ozone hole' is a necessarily new phenomonon that represents a fundlemental danger to humans and other life on earth.

    There is an interesting essay [with an excellent bibliography] here [sepp.org] Which endeavors to critically debunk the rationale behind the scaremongering widely perpetuated by the mainstream media. Many respected scientists have had critical disagreements over the validity of the 'ozone problem', yet this has suprisingly been absent throughout the long history of mainstream media coverage of the topic.

    Think what you will, I won't say I am wholly convinced one way or another, but this is well worth reading. Even if you are an adamently radical environmentalist, if nothing else it is good to know thine enemy. ;)

    The preliminary introduction is a bit slow, if you're in a hurry, skip down to the subsection titled SCIENTIFIC UNCERTAINTIES AND CONTROVERSIES and as well to CONCERNS ABOUT SKIN CANCER , which I found particularly interesting.

    It wouldn't be the first time that national hysteria (in this case, international) got out of hand, fed by a singular drum-beat of media hype, leading to bad policy. [Remeber columbine, the drug way, countless others?]

    It's valuable to challege orthodoxy, and I found this article a fascinating read. You should check it out.


    --
    man sig
  • by Mad Hughagi ( 193374 ) on Monday October 16, 2000 @05:42AM (#703167) Homepage Journal

    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.

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