Jennifer Marohasy

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Low Temperatures Over Antarctica

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I received the following note:

“Hi Jennifer,

Tonight the ABC news reported on the large ozone hole over the Antarctic.

On the news, first it was claimed that the large hole was responsible for the record cold weather there. Then that the cold weather was destroying the ozone and causing the hole.

Can you have it both ways?

Cheers, Helen Mahar”

According to ABC New Online:

“Dr Paul Fraser from the CSIRO says the lowest temperatures ever recorded in Antarctica’s upper stratosphere this winter – minus 85 degrees – are the cause.

“It’s certainly the coldest we have ever seen and it requires very cold temperatures to get very significant ozone depletion,” Dr Fraser said.”

And how does this fit with the IPCC global warming projections?

Reader Interactions

Comments

  2. George McC says

    And at the other end of the planet, Svalbard or Spitzbergen near the North pole had the warmest summer recorded since 1906 …

  3. Paul Biggs says

    We could blame that pesky Sun:

    Solar cycle effect delays onset of ozone recovery

    M. Dameris

    Institut für Physik der Atmosphäre, DLR-Overapprehensive, Wessling, Germany

    S. Matthes

    Institut für Physik der Atmosphäre, DLR-Overapprehensive, Wessling, Germany

    R. Deckert

    Institut für Physik der Atmosphäre, DLR-Overapprehensive, Wessling, Germany

    V. Grewe

    Institut für Physik der Atmosphäre, DLR-Overapprehensive, Wessling, Germany

    M. Ponater

    Institut für Physik der Atmosphäre, DLR-Overapprehensive, Wessling, Germany

    Abstract

    Short- and long-term changes of total ozone are investigated by means of an
    ensemble simulation with the coupled chemistry-climate model E39/C for the
    period 1960 to 2020. Past total ozone changes are well simulated on both,
    long (decadal) and short (monthly) timescales. Even the 2002 Antarctic ozone
    anomaly appears in the ensemble. The model results indicate that the 11-year
    solar cycle will delay the onset of a sustained ozone recovery. The lowest
    global mean total ozone values occur between 2005 and 2010, although
    stratospheric chlorine loading is assumed to decline after 2000. E39/C
    results exhibit a significant increase of total ozone after the beginning of
    the next decade, following the upcoming solar minimum. The observed ozone
    increase in the second half of the 1990s is reproduced by E39/C and is
    identified as a combined post-Pinatubo and solar cycle effect rather than
    the beginning of a sustainable ozone recovery.

    Received 28 September 2005; accepted 3 January 2006; published 8 February
    2006.

    Index Terms: 0325 Atmospheric Composition and Structure: Evolution of the
    atmosphere (1610, 8125); 0340 Atmospheric Composition and Structure: Middle
    atmosphere: composition and chemistry; 0370 Atmospheric Composition and
    Structure: Volcanic effects (8409).

    GEOPHYSICAL RESEARCH LETTERS, VOL. 33, L03806, doi:10.1029/2005GL024741,
    2006

    http://www.agu.org/pubs/crossref/2006/2005GL024741.shtml

  4. Ann Novek says

    George, I’m glad that you mentioned this… You have personally been up in the Barents sea and can document the warming trend… OK, it seems like we agree on this issue and maybe not so much on other topics…but you are worth a glass of wine or beer for this comment…

  6. coby says

    Hi Jennifer,

    A cooling stratosphere is actually consistent with GW theory and this is one of the model predictions that satellite measurements were able to confirm.

    But the poles both remain the most difficult to model well. Ozone depletion also causes stratospheric cooling which complicates both expectations and attribution of observations.

  7. George McC says

    Anne,

    I´m no climatologist ( or whatever they are called ) …. but the pattern I´ve seen in the Barents personally tends towards warmer summers and colder winters – having said that, drift/pack ice has also been very far south at times the past few years … go figure.. maybe one of the climate folks can explain…

    Here´s a new newspaper for you anne ..

    http://www.svalbardposten.no/index.cfm

  8. George McC says

    Anne,

    I´m no climatologist ( or whatever they are called ) …. but the pattern I´ve seen in the Barents personally tends towards warmer summers and colder winters – having said that, drift/pack ice has also been very far south in Spring at times the past few years … go figure.. maybe one of the climate folks can explain…

    Here´s a new newspaper for you anne ..

    http://www.svalbardposten.no/index.cfm

  9. Schiller Thurkettle says

    Given the comments of the AGW theorists, I propose the formation of a stock company that will invest in polar real estate. Previously thought worthless, the poles will now be host to seaside hotels, golf courses, and better yet–people who crave a near-instant suntan.

    Surely the predictions of AGW theorists are sufficient to spur significant investments in polar real estate, with a concomitant, indeed, exponential rise in value.

    Startup funds for this venture will come from the sale of a rather dramatic and historical bridge.

  10. Davey Gam Esq. says

    Now you are sounding like an interdisciplinary Human Ecologist, Schiller. Well done – I am singing your Ode to Joy as I type.

  11. Helen Mahar says

    Thank you Coby

    You are throwing some sense on the apparent inconsistency I heard on the ABC News last night.

    Your comment “ozone depletion also causes stratospheric cooling” lines up with the first claim I heard – that the record low temperatures were caused by ozone depletion. Then Dr Frazer’s comment “it requires very cold temperatures to get significant ozone depletion” was the scond comment.

    So I have the following questions:

    1 Does the ozone layer have a ‘greenhouse effect’?

    2 What caused the ozone layer to deplete sufficiently to cause the abnormally cold temperatures which are now further depleting the ozone layer? Or to paraphrase this question; which comes first, the chicken or the egg?

    3 Do we really know enough about the ozone layer to know what is going on?

  12. Ian Mott says

    Schiller, lets call it “the South Sea Bubble Co”.

    Helen, the answer is “all of the above”. It is fundamental to the operation of all shonks, spivs and green planeteers that the language is debased to such an extent that words can mean anything they want them to mean at any time, place and situation they find themselves in.

    And a little problem with cause and effect is hardly a problem for these great communicators. They will just cruise along, as per the London Institute of Shonks, and imply that the research is no longer in dispute and that all reputable scientists in the field are in agreement.

    You’re not one of those ozone sceptics, are you?

  13. Luke says

    Helen – there is also some evidence that stratospheric ozone depletion is also affecting the Antarctic Oscillation and thus the south west WA region’s rainfall.

    But it’s a complex story: http://www.csiro.au/csiro/content/standard/ps18l,,.html

    Science 3 May 2002:
    Vol. 296. no. 5569, pp. 895 – 899

    Interpretation of Recent Southern Hemisphere Climate Change

    David W. J. Thompson,1* Susan Solomon2

    Climate variability in the high-latitude Southern Hemisphere (SH) is dominated by the SH annular mode, a large-scale pattern of variability characterized by fluctuations in the strength of the circumpolar vortex. We present evidence that recent trends in the SH tropospheric circulation can be interpreted as a bias toward the high-index polarity of this pattern, with stronger westerly flow encircling the polar cap. It is argued that the largest and most significant tropospheric trends can be traced to recent trends in the lower stratospheric polar vortex, which are due largely to photochemical ozone losses. During the summer-fall season, the trend toward stronger circumpolar flow has contributed substantially to the observed warming over the Antarctic Peninsula and Patagonia and to the cooling over eastern Antarctica and the Antarctic plateau.

  14. Ann Novek says

    George,

    Think the issue is so complex that nobody really doesn’t know why some winters have been colder than normally when summer temperatures have had a tendency to increase.

    I’m not familiar with the issue but some mechanisms seem to be:

    1) The North Atlantic Oscillation( NOA). When winters are colder in Labrador they are warmer in Barents Sea and vice versa.

    2) The variability in ice coverage is closely linked to the temperature of inflowing Atlantic water.

    3) Variability in low pressure passages and cloud cover has a strong influence on the winter athmosphere- ocean heat exchange.

    We also know that melting of the Arctic ice cap impacts water temperature in the Norwegian Sea and the Barents Sea.( This might indicate the scenario that you have described, dunno…)

    Thanks for sending the link to Svalbardposten, read also in my local paper that people from Thailand were the biggest group of foreigners working in Svalbard…

    Check out my whaling post today!

  15. Helen Mahar says

    Thanks for the heat, Ian. But I am asking serious questions as a layperson, and I am after some light.

    Luke, you have not addressed my main question (2) unless you are implying that these various antarctic vortexes (winds) and oscillations acutally move ozone away from the south pole, triggering the drop in high level temperature, which further depletes the ozone around the south pole?

  16. coby says

    Hi Helen,

    You are pushing the boundaries of my knowledge of these details, so I have to be a bit vague and general.

    You asked:
    1 Does the ozone layer have a ‘greenhouse effect’?

    Ozone is greenhouse gas and in the troposhpere appears as one of the positive climate forcings identified in the IPCC report:
    http://www.grida.no/climate/ipcc_tar/wg1/figspm-3.htm

    In the stratosphere I believe its property of absorbing ultra violet, hence warming the stratosphere, provides its only significant role, though I can only speculate as to why. Perhaps the layer is just too thin for depletion to cause any significant negative forcing.

    2 What caused the ozone layer to deplete sufficiently to cause the abnormally cold temperatures which are now further depleting the ozone layer? Or to paraphrase this question; which comes first, the chicken or the egg?

    I imagine this is just the standard CFC ozone depletion effect, I guess that would be the chicken 🙂

    3 Do we really know enough about the ozone layer to know what is going on?

    Well, how much is enough? Enough to have identified a very serious developing problem, not enough to have predicted just how much and where the ozone would be most effected. I would guess we know alot more now, but surely there are lots of problems left to solve! I don’t think there is anything scientifically controversial about the basic cause and effect of ozone depletion.

    Looks like alot of good info here:
    http://en.wikipedia.org/wiki/Ozone_layer

  17. John Fabray says

    I saw this piece on the ABC as well. Have we been misled about the causes of the ozone hole? I always thought it was caused by chlorofluorocarbons released into the atmosphere and that it was getting smaller as the concentration of these substances in the air decreased. Now we find out that record low temperatures in the Antarctic are causing the hole to get bigger. What happened to global warming? – not mentioned in the report surprisingly for the ABC – weren’t the poles supposed to warm up more quickly than anywhere else? Certainly raises a lot of questions.

  18. coby says

    John,

    There is no natural law that says an observed change can have only one cause, in fact it is nearly always the opposite. CFC’s cause ozone depletion, there is no reason to doubt this. Ozone depletion causes cooling in the stratosphere. GW from an enhanced greenhouse effect causes warming at the surface and troposphere, but it also causes cooling in the stratosphere.

    I think that the ozone was thought to be recovering also, but recently they are finding surprises. It is complicated.

    Yes the poles are supposed to warm more and the north pole definately is. The south pole is surrounded by the vast southern ocean which provides alot of thermal inertia, so the south pole is not showing the same degree of warming as the north. There is some basic info on that issue here:
    http://illconsidered.blogspot.com/2006/05/antarctic-sea-ice-is-increasing.html

  19. Helen Mahar says

    Coby,
    I followed the Wikepedia links, and I think I can put the ozone hole story in layman’s language. Ozone is formed by chemical reactions driven by the sun, so most is formed over or near the tropics. It slowly rises, then is slowly transported towards the poles, where it forms the highest atmospheric concentrations.

    From winter through spring strong westerly winds start to circulate around Antarctica creating a ‘polar vortex”, trapping and chilling the air. In the extreme cold of winter, polar stratospheric clouds form. These low temperature clouds form particles of either nitric acid or ice. Both types of clouds provide surfaces for chemical reactions which convert chlorine type compounds into free radicals.

    Come spring, and sunlight melts the clouds, releases the compounds and drives the chemical reactions which deplete up to 50% of the ozone trapped around the Antarctic. Thus forming the ozone hole. This destruction process stops around December, when the westerly winds stop, and warmer, ozone rich air moves in from lower latitudes. This destruction is an annual event, but is much more severe over Antarctica because that is the colder of the two poles.

    So John Fabray be reassured, be very reassured. The chlorofluorocarbons are still the ultimate cause of the ozone hole, according to the Wikepedia information.

    But I cannot find anywhere in that Wikepedia article any indication that lower ozone levels cause lower antarctic winter temperatures. Which was the claim on the ABC News program which started my questions. So where did the ABC get that from?

    Ian Mott, if something does not add up I ask questions. My pedantic bookkeeper’s mind, I suppose. It’s when the explanations do not add up that I turn skeptic. And I still have questions about this topic.

    The chicken and egg problem is still there.

  20. coby says

    ” lower ozone levels cause lower antarctic winter temperatures”

    Don’t forget that applies to the stratospheric temperatures only. Thanks for that summary.

  22. coby says

    Paul,

    You are too intelligent to miss the distinction, pointed out at least three times in this thread, between the stratosphere and the surface. The surface is warming, the stratosphere is cooling. Therefore a story about surface warming is not in conflict with a story about stratospheric cooling.

    This is why climate sceptics get so little respect from the mainstream, it appears you guys do these things on purpose.

  23. Pinxi says

    Perhaps Paul too would kindly oblige by clarifying the precise nature of his scepticism (see next thread forward)

  25. Dan McLuskey says

    It is worth noting that the supposed “hole” in the ozone layer is located directly over Mount Erebus, and active volcano in the Antarctic.

    Mount Erebus emits about 7,000,000 tonnes of methane per year, a natural effect.

    And what does methane do to ozone? Destroys it.

  26. Helen Mahar says

    Hi Coby
    Back again after a break. I think I can work my way through my own questions now.

    1 Does the ozone layer have a greenhouse effect? On the currently accepted science, yes.

    2 What caused the ozone layer to deplete sufficiently to cause the abnormally cold stratospheric temperatures which are now fuelling further depletion of the ozone layer.

    This is actually two questions.

    The second part is easy to deal with. Abnormally low polar stratospheric temperatures significantly increase ozone depletion. No problem with that.

    The first part of that question is where the problems are. The question should be: does depletion of the ozone layer cause abnormally cold winter polar temperatures?

    Given that the Wikepedia article makes no such claim, that the ABC news program provided no scientific backing for this claim, that the stratospheric ozone related greenhouse effect is driven by the sun’s UV rays, that atmospheric ozone concentrations are greatest at the poles, and highest in winter, that the polar stratospheric clouds form in winter, in darkness, and that both ozone formation and ozone depletion are driven by the sun’s energy, I doubt that ozone concentrations have much to do with causing abnormally cold polar stratosopheric – or surface – temperatures.

    So what else could cause abnormally cold polar winter temperatures. Paul Biggs’ earlier blog on the eleven year solar cycle indicates a plausible culprit. The model quoted, E39/C, also predicts that the solar cycle will delay the onset of sustainable ozone recovery until after 2010. This lines up with something else that Dr Paul Frazer of the CSIRO said on the ABC, if I remember rightly; that the huge ozone hole had set back ozone recovery by 5 years.

    The sun drives the ozone cycle, and I see no reason why it should not also drive polar temperatures.

    As regards the chicken and egg concern, it is probably not relevant, and thank goodness for that. Imagine ozone, which protects us from UV rays, caught in a self-reinforcing destruction loop. Now that would be a catasrophe.

    Thank you Coby and Paul Biggs for your helpful leads. It’s been a great ride!

  27. Paul Biggs says

    Coby ‘Unexpected’ was my point – not predicted by climate models. Surface temperature data may have a warm bias, and ‘global average temperature’ is a poor metric.

    Nice post Helen, you saved me posting about UV from the Sun driving Ozone in the upper atmosphere.

    Diverging slightly, Ozone has been responsible for one-third to one-half of observed Arctic warming in winter and spring(Shindell).

  28. Davey Gam Esq. says

    I am a complete climate ignoramus. However, I believe those who say it is changing. Has it not always done so? I like the sound of Dan McCluskey’s Mount Erebus theory. Some time ago I asked if the warming of the Antarctic Peninsula could possibly be due to volcanic activity, but got no reply. Might El Nino be due to tectonic subduction? Isn’t the Pacific floor diving under Asia and America as the Earth shrinks? Anybody like to coach me on this? Could bits break off now and again, plopping into the magma, and causing an upwelling of hot water? One thing only I know, and that is that I know nothing.

  29. Luke says

    Davey – yes of course climate has always been changing. But how fast? With what outcomes? Outcomes don’t have to make you happy (or sad). And we now have 6 billion people on Earth and what – 30 days food security. We haven’t done this trick before. And we know that usually a big drought, flood, heatwave or hurricane already can kill many people – so we’re already living with worrisome climate issues.

    Yep volcanoes are good theory – but Macquarie Island is warming too.

    http://www.abc.net.au/quantum/scripts98/9802/script.htm

    http://aadc-maps.aad.gov.au/aadc/soe/display_indicator.cfm?soe_id=1

    And see http://uwnews.washington.edu/ni/article.asp?articleID=26515

    The main reason that Antarctica appears to have cooled during the 1990s is that a natural phenomenon called the Antarctic Oscillation, or Southern Annular Mode, was largely in its positive phase during that time. The Antarctic Oscillation is so named because atmospheric pressure in far southern latitudes randomly oscillates between positive and negative phases. During the positive phase, a vortex of wind is tightly focused on the polar region and prevents warmer air from mixing with the frigid polar air, which keeps Antarctica colder.

    So the middle of Antarctica is walled off “meteorologically”

    El Ninos aren’t climate change – they’ve been round for 1,000s or years. Climate change end up affecting them but that’s till speculative. http://en.wikipedia.org/wiki/El_Ni%C3%B1o gives well known for El Nino – there will be differnet views – there are people talking about “tectonic” connections but I don’t think it’s a dominant theory.

  30. Helen Mahar says

    Luke,
    In regards to your tongue-in-cheek post about Antarctic temperatures rising by 0.2C in the last 150 years, I thought I would check it out, to see if you were just setting loose a rabbit to chase down a hole.

    I was pleasantly surprised. This thread is certainly interesting, and adds to the subjects in this post. Well worth the read. It is a complicated world, isn’t it? Thank You.