Slashdot Mirror

← Back to Stories (view on slashdot.org)

Antarctic Ozone Hole Shrinks 30 Percent

Posted by kdawson on from the but-don't-spray-cfc's-in-celebration dept.

polar red sends us news of a story that many outlets have picked up from a European Space Agency press release: the Antarctic ozone hole is 30% smaller than it was during the previous record year. It's still about the size of North America. "Scientists say this year's smaller hole... is due to natural variations in temperature and atmospheric dynamics... and is not indicative of a long-term trend. 'Although the hole is somewhat smaller than usual, we cannot conclude from this that the ozone layer is recovering already,' [one researcher said]."

17 of 436 comments (clear)

  1. Environmental spin by Hal_Porter · · Score: 5, Informative

    Very strange effect. It seems like lots of studies are done. The ones that show drastic environmental collapse are reported very widely. In this case the news seems good and there isn't an alternative study so we get the comment 'Although the hole is somewhat smaller than usual, we cannot conclude from this that the ozone layer is recovering already'. So the studies may be ok scientfically but picking the outliers which show immininent catastrophe and if that is impossible adding comments that the catastrophe might still be present is not.

    So bad news is bad news. Good news means we can't conclude anything.

    It reminds me of the 'worst headline ever' : 'Small earthquake : not many killed'. If you want to attract attention, I guess you need a bit of drama.

    But maybe I'm complacent and we'll all die of avian flu or global warming or a meltdown in the financial markets causing a collapse of our civilisation.

    --
    echo -e 'global _start\n _start:\n mov eax, 2\n int 80h\n jmp _start' > a.asm; nasm a.asm -f elf; ld a.o -o a;
  2. Re:not much historic data on hole by PlatyPaul · · Score: 2, Informative

    Well, even if "going apeshit" was the right response, it'll still take decades to repair the ozone layer completely....

    --
    Misery loves company. Online misery loves unsuspecting random strangers.
  3. Re:global warming - I'll bite by Anonymous Coward · · Score: 1, Informative

    Well, actually 100% of the global warming is from the sun: Take the sun away, and I assure you it will not get warmer even a fraction of a degree, and no amount of CO2 will change that!

  4. Also unreported by the major media by Kohath · · Score: 3, Informative

    Also unreported by the major media is the new crack in the consensus on ozone depletion in general. There are new indications that the mechanism scientists told us was destroying ozone might not be doing what they thought.

    This is the only info available because the press won't report it and I don't have a subscription to the journal "Nature".

    1. Re:Also unreported by the major media by Anonymous Coward · · Score: 3, Informative

      Well since I do have a subscription to Nature magazine, let me summarize it briefly:

      They report on careful measurements of the photolysis of Cl2O2, which has been a key reaction in ozone climate models for a long time. The measurements indicated that the photolysis reaction was much slower than previously believed (~1/10th the speed). If this is true, then it of course has a significant impact on the ozone component of climate models. The article reports that this would mean that instead of being able to account for nearly all the observed loss of ozone, we can only account for 40% of it.

      This is only a single study, however, so it needs to be double-checked by other labs. But, it is coming from a very trustworthy source (NASA JPL), so the climatology community is taking the results seriously. They are now searching for other chemical pathways (both involving and not involving the previous candidates, such as CFCs) that can help explain the observed changes in ozone.

      This new knowledge will certainly help in refining climate models to better predict both future trends and possible outcome scenarios for various ranges of human behavior. It should be noted, however, that other evidence (besides the reaction rate models that have now been brought into question) links CFCs and halons with atmospheric ozone, so any future explanation must reconcile all of those observations. Moreover this new study doesn't change the overall picture that is emerging about anthropogenic links to climate.

      This new study is certainly important. But science is complicated, requiring hundreds of studies to prove any particular point to the satisfaction of the community. So we should be careful to draw any conclusions from this one study until it has been verified and reconciled with other data.

  5. Because they know what they're talking about? by Eevee · · Score: 2, Informative

    If you accidentally read the fine article ('cause we know nobody actually tries to read it), you'll see that first off, it's 30% smaller than the record-setting ozone hole from last year. So while the value for this year is down, it looks to be about at or just slightly below the average level for the 90s. (So far, the 00s seem to have a lot of swings up and down, making it hard to visually estimate off the graph.) Furthermore, this year the hole was less centered over the South Pole than was the case in other years; this allows more warm air into the area which results in less ozone depletion. So the article has good reasons for the caution.

  6. Re:not much historic data on hole by Pentagram · · Score: 2, Informative

    It's impossible to embarrass those who produce bad science.

    Well, I'm going to try with you.

    The link from man-made CFCs to ozone depletion was tenuous at best.

    False. Try educating yourself.

    Preliminary investigation into volcanoes shows that the amount of chlorine they spew dwarfs what man produces, and it is lost high in the atmosphere, instead of feet from the ground.

    Absolute bollocks. See here.

    But, it really troubles me to see a lot of the bad science that is repeated over and over without being checked.

    Irony, thy name is uigrad_2000.

  7. Re: Conspiracy Theory! ... what are you smoking? by MillionthMonkey · · Score: 4, Informative
    You have got to be kidding! We changed our behaviour and it worked? In such a short time frame? You know what? That's utter BS and most climatologists would concur.

    It may not be conclusive that the hole shrank because of what we did, but we definitely reduced the stratospheric CFC concentrations:

    There are no sinks for CFCs in the lower atmosphere. As a result they are transported to the stratosphere (10 to 50km altitude) where they are broken down by UV radiation, releasing free chlorine atoms which cause significant ozone depletion. In 1998 global atmospheric concentrations of on of the CFCs, CFC-11 was 268pptv. Over the past few decades CFCs 11,12 and 113 have increased more rapidly (on a percent basis) than any other greenhouse gas, but there is now clear evidence that growth rates of CFCs have slowed significantly in the aftermath of the Montreal Protocol (1985) to prevent ozone depletion. In fact, the 1998 atmospheric concentration of CFC-11 was lower than the concentration 5 years earlier. The total forcing value for Chlorofluorocarbons is +0.3Wm-2. This includes CFC-11, 12, 113, 114, 115, methylchloroform and carbon tetrachloride. Under the Montreal Protocol, the production of CFCs 11, 12 and 113 has been successfully phased out since 1995. However, despite these measures, the concentration of CFCs in the atmosphere will remain significant into the next century because of the relatively long lifetimes associated with these compounds.
    There's probably better stuff to be Googled up but I'm going to be late for work.

    But they spend better than half their time screaming "M-Fer, I want more research funding". Or so my 15 years in academia and government research leads me to believe.

    I find your credentialism unconvincing- in fact you don't know how many years I have over you. I've been involved in those filings myself and am familiar with what happens. What I find offensive are the accusations that the entire scientific consensus on the issue is attributable to a desire for research funding. Most scientists do not receive funding for climate research. And it's not as if climate research dollars are even in short supply- after all, allocating that money and "waiting until the results are in" is basically how the president has dealt with all these problems.
  8. Re:not much historic data on hole by MrMickS · · Score: 2, Informative
    Pragmatic environmental policies? The current western political structures don't allow for this. They are all designed for the short term, as such long term policies (of the 10 year plus kind) don't really have a lot of sway. They aren't something that most politicians will be still around to claim credit for and worse they may give the opposition chance to claim credit for something that you carried out. The era of the career politician beholden only to the state is detrimental to real democracy and real long term aims.

    The reality is that we don't have a great deal of data, not when you talk in geological terms, and we are then using it to extrapolate into systems that we don't really understand. We have hunches, but nothing definitive. We know some things, we don't know the whole picture. Its a shame but true.

    --
    You may think me a tired, old, cynic. I'd have to disagree about the tired bit.
  9. Re:Tell me something... by Anonymous Coward · · Score: 3, Informative

    I am old enough to remember this. The "second ice age" and "over population" folks were pretty much one-in-the-same. That started in the 60's. I can still remember the TV commercials when I was a kid crying about over populating the planet; "We'll all be a doublin' in thirty-two years". From the same time period I can remember newspaper articles whining about the coming second ice age; "It's already getting colder!". Both congealed into the air/water pollution crowd in the 70's. The 80's saw the same groups briefly trotting out over population once again to add to their pollution sideshow. Then they discovered "ozone depletion". In the late 80's and 90's it was "global warming". Now it's "catastrophic climate change". In *all* cases it's been the same group of people screaming; "the sky is falling".

  10. Re:Conspiracy theory by jayteedee · · Score: 3, Informative

    When then in YOUR universe, you haven't been paying much attention to ozone hole research. They have been predicting that the hole would take 30-100 years to recover. BUT, more importantly, their models don't predict this kind of behavior. Which DIRECTLY brings into question their models in most if not ALL areas of ozone hole research. We, as scientist/engineers/etc, don't expect perfect models, but this kind of errant behavior signals a huge OOPS to the other scientists. Look at the 1st chart here: http://earthobservatory.nasa.gov/Newsroom/NewImages/images.php3?img_id=17436 (NOTICE this is a NOAA chart) and see that the average and the hardly vary by 30%, but what the article states is "Antarctic ozone hole is 30% smaller than it was during the previous RECORD year". My emphasis. 5-10% beyond a record year would be acceptable. 30% beyond a record year (which yields 60-70% beyond the average) is a BIG DEAL. At least some of the models are suspect, end of story (unless you doing politics, then make up your own story).

    --
    Religion and science are both 90% crap..but that doesn't negate the other 10%.
  11. Re:summary... by Anonymous Coward · · Score: 1, Informative

    the ozone depletion problem was solved with the ratification of the Montreal Protocol


    maybe, maybe not
  12. Re:summary... by irenaeous · · Score: 2, Informative

    You make excellent points, so I apologize for wishing to insert a clarification. The depletion of the ozone layer is a separate issue from global warming. Ozone depletion is caused by chemical pollutants, particularly CFCs (chloroflorocarbons), that catalyze chemical reactions in the upper atmosphere that break down ozone. These pollutants have leveled off and are in decline thanks to the 1987 Montreal Protocols. Global warming itself is that the direct cause of Ozone depletion in the upper atmosphere.

    That said, global warming may be making matters worse for the Ozone due to indirect effects (see this article from a couple years ago.

    Also, I would not regard the production of green house gases as less important the toxic chemical pollution over the long haul. Some level of global warming is now more or less inevitable, but if we do nothing now, then things in the long haul could get much worse.

  13. You've got your numbers reversed by Ambitwistor · · Score: 4, Informative

    but what the article states is "Antarctic ozone hole is 30% smaller than it was during the previous RECORD year". My emphasis. 5-10% beyond a record year would be acceptable. 30% beyond a record year (which yields 60-70% beyond the average) is a BIG DEAL. 30% beyond the record year is not 60-70% beyond the average: you're confusing the signs. The current hole is 30% SMALLER than last year's LARGEST size — i.e., closer to the average size.

    We've seen interannual jumps of 30% in ozone hole size before (e.g., here); it's within the range of natural variation, and as such, does not indicate some total failure of the models.
  14. Re:Tell me something... by Anonymous Coward · · Score: 1, Informative


    Here you go. Link to scans from actual newspaper headlines.

    http://www.saveportland.com/Climate/index.html/

    A summary.

    1895: Global Cooling!
    1912: Global Cooling!
    1922: Ice Age Coming!
    1932: Global Warming! Melting Polar Ice caps to flood world!
    1952: Switch to Global Cooling!
    1969: Global Warming! Artic will soon be open ocean!
    1974: Ice Age Coming!

    So you see, we've already been through FIVE ice-age scares and TWO global warming scares since newspapers were invented. I guess were due for another global warming scare.

  15. Re:summary... by IamTheRealMike · · Score: 2, Informative

    The prophets of 1970 said: -We would be out of oil by now

    No, what was actually said was that in the year 2000 oil production would peak and then start to decline. That's not the same as "oil running out" - indeed, oil will probably never run out. Production rates will get so low however that we might as well have run out. This prediction was made by a petroleum geologist working for Shell, and was based on extrapolation of trends and observed decline rates in existing fields.

    Well, oil production didn't peak in 2000. I guess that means it'll never peak! Oh, wait. Shortly after his prediction, the world went through the oil shocks of the late 70s and 80s, which if you plot the production graph pushed the peak date forward by about 7 years. That means if you adjust Hubberts prediction for the oil shocks, production should be levelling off about now. Is it? Well, yes.

  16. Re:Early Data Points by Anonymous Coward · · Score: 2, Informative

    So many uninformed people in this thread, it's quite depressing really...

    The hole in located in the south, because the temperatures in the southern stratosphere are lower than in the north. They are lower than -78C, which is the minimum temperature needed for CFC's to break down O3. This year's 30% decrease in size compared to the RECORD size of last year is caused by the temperatures over the south pole.

    http://www.cpc.ncep.noaa.gov/products/stratosphere/strat-trop/gif_files/time_pres_TEMP_ANOM_ALL_SH_2007.gif

    This graph shows this year's temperature anomalies (up until October obviously) over the south pole. Notice the fact that, though it was on average a bit too cold, it was much too warm last month.

    Here are the average temperatures:

    http://www.cpc.ncep.noaa.gov/products/stratosphere/strat-trop/gif_files/time_pres_TEMP_MEAN_ALL_SH_2007.gif

    -78C is gone, and so is the massive breakdown of O3. Much earlier than last year.

    Now compare to last year.

    http://www.cpc.ncep.noaa.gov/products/stratosphere/strat-trop/gif_files/time_pres_TEMP_ANOM_ALL_SH_2006.gif

    Except for one small blob, it was too cold during the entire spring.

    Average temperatures:

    http://www.cpc.ncep.noaa.gov/products/stratosphere/strat-trop/gif_files/time_pres_TEMP_MEAN_ALL_SH_2006.gif

    Easily -78C well up until November. An entire month extra of O3 breakdown. This is what caused the record size. Things are pretty much back to normal now, so I don't see what the fuss is all about: there still is a need to decrease the amount of CFC's, because the more there are up there, the more damage those cold months can cause.

    Why are you people not checking the facts? Are you really waiting to jump to the next conclusion? To post the next big "conspiracy theory"? WTF are you people doing on Slashdot? You are childish cynics, not nerds. You lost your inquisitive attitude and you just mindlessly regurgitate whatever you're being fed.