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Why Arctic sea ice shouldn't leave anyone cold

Posted on 27 August 2012 by Neven

In the past week the Arctic sea ice cover reached an all-time low, several weeks before previous records, several weeks before the end of the melting season. The long-term decline of Arctic sea ice has been incredibly fast, and at this point a sudden reversal of events doesn't seem likely. The question no longer seems to be "will we see an ice-free Arctic?" but "how soon will we see it?". By running the Arctic Sea Ice blog for the past three years I've learned much about the importance of Arctic sea ice. With the help of Kevin McKinney I've written the piece below, which is a summary of all the potential consequences of disappearing Arctic sea ice.

Arctic sea ice became a recurrent feature on planet Earth around 47 million years ago. Since the start of the current ice age, about 2.5 million years ago, the Arctic Ocean has been completely covered with sea ice. Only during interglacials, like the one we are in now, does some of the sea ice melt during summer, when the top of the planet is oriented a bit more towards the Sun and receives large amounts of sunlight for several summer months. Even then, when winter starts, the ice-free portion of the Arctic Ocean freezes over again with a new layer of sea ice.

1-kinnard2011Since the dawn of human civilization, 5000 to 8000 years ago, this annual ebb and flow of melting and freezing Arctic sea ice has been more or less consistent. There were periods when more ice melted during summer, and periods when less melted. However, a radical shift has occurred in recent times. Ever since satellites allowed a detailed view of the Arctic and its ice, a pronounced decrease in summer sea ice cover has been observed (with this year setting a new record low). When the IPCC released its Fourth Assessment Report in 2007, it was generally thought that the Arctic could become ice-free somewhere near the end of this century. But changes in the Arctic have progressed at such speed that most experts now think 2030 might see an ice-free Arctic for the first time. Some say it could even happen this decade.

2-albedofeedbackWhat makes this event significant, is the role Arctic sea ice plays as a reflector of solar energy. Ice is white and therefore reflects a large part of incoming sunlight back out to space. But where there is no ice, dark ocean water absorbs most of the sunlight and thus heats up. The less ice there is, the more the water heats up, melting more ice. This feedback has all kinds of consequences for the Arctic region. Disappearing ice can be good for species such as tiny algae that profit from the warmer waters and extended growing season, but no sea ice could spell catastrophe for larger animals that hunt or give birth to offspring on the ice. Rapidly changing conditions also have repercussions for human populations whose income and culture depend on sea ice. Their communities literally melt and wash away as the sea ice no longer acts as a buffer to weaken wave action.

3-jetstreamBut what happens in the Arctic, doesn't stay in the Arctic. The rapid disappearance of sea ice cover can have consequences that are felt all over the Northern Hemisphere, due to the effects it has on atmospheric patterns. As the ice pack becomes smaller ever earlier into the melting season, more and more sunlight gets soaked up by dark ocean waters, effectively warming up the ocean. The heat and moisture that are then released to the atmosphere in fall and winter could be leading to disturbances of the jet stream, the high-altitude wind that separates warm air to its south from cold air to the north. A destabilized jet stream becomes more 'wavy', allowing frigid air to plunge farther south, a possible factor in the extreme winters that were experienced all around the Northern Hemisphere in recent years. Another side-effect is that as the jet stream waves become larger, they slow down or even stall at times, leading to a significant increase in so-called blocking events. These cause extreme weather simply because they lead to unusually prolonged conditions of one type or another. The recent prolonged heatwave, drought and wildfires in the USA are one example of what can happen; another is the cool, dull and extremely wet first half of summer 2012 in the UK and other parts of Eurasia.

4-greenlandsurfacemeltjuly2012The accumulation of heat in Arctic waters also influences other frozen parts of the Arctic, such as glaciers and ice caps on Greenland and in the Canadian Archipelago. As there is less and less sea ice to act as a buffer, more energy can go into melting glaciers from below and warming the air above them. This has a marked effect on Greenland's marine-terminating glaciers and the Greenland Ice Sheet. Not only are glaciers flowing faster towards sea, but there is also a rapid increase in the summer surface melt Greenland experiences, leading to accelerating mass loss from the Greenland Ice Sheet. As the Arctic warms, an increased contribution to sea level rise is inevitable.

5-permafrostdistributionAnother way Arctic warming could have worldwide consequences is through its influence on permafrost. Permanently frozen soils worldwide contain 1400-1700 Gigatons of carbon, about four times more than all the carbon emitted by human activity in modern times. A 2008 study found that a period of abrupt sea-ice loss could lead to rapid soil thaw, as far as 900 miles inland. Apart from widespread damage to infrastructure (roads, houses) in northern territories, resulting annual carbon emissions could eventually amount to 15-35 percent of today’s yearly emissions from human activities, making the reduction of greenhouse gases in the atmosphere a much more difficult task.

6-methaneconcentrationAn even more worrying potential source of greenhouse gases is the methane in the seabed of the Arctic Ocean, notably off the coast of Siberia. These so-called clathrates contain an estimated 1400 Gigatons of methane, a more potent though shorter-lived greenhouse gas than carbon dioxide. Methane clathrate, a form of water ice that contains a large amount of methane within its crystal structure, remains stable under a combination of high pressure and low temperature. At a depth of 50 meters or less the East Siberian Arctic Shelf contains the shallowest methane clathrate deposits, and is thus most vulnerable to rising water temperatures. Current methane concentrations in the Arctic already average about 1.90 parts per million, the highest in 400,000 years.

7-russiaplantsflagApart from these unrecoverable sources of fossil fuel the Arctic is also endowed with large amounts of recoverable oil and natural gas. As the sea ice retreats, the Arctic's fossil treasures are eyed greedily by large corporations and nations bordering the Arctic Ocean. Not only might this lead to geopolitical tensions in a world where energy is rapidly becoming more expensive, it is also highly ironic that the most likely cause of the disappearance of Arctic sea ice - the extraction and burning of fossil fuels - could lead to more extraction of said fuels. Another feedback loop.

News articles referring to the Arctic and its sea ice usually have pictures of polar bears accompanying the text. But although many animals in the Arctic will be impacted negatively by the vanishing of Arctic sea ice, much more is at stake. After thousands of years in which the sea ice played a vital role in the relatively stable conditions under which modern civilization, agriculture and a 7 billion strong world population could develop, it increasingly looks as if warming caused by the emission of greenhouse gases is bringing an end to these stable conditions. Whether there still is time to save the Arctic sea ice, is difficult to tell, but consequences will not disappear when the ice is gone. It seems these can only be mitigated by keeping fossil fuels in the ground and out of the air. Whichever way you look at it, business-as-usual is not an option.

 

For more information on Arctic sea ice, check out the Arctic Sea Ice blog.

Images used:

Arctic sea ice extent reconstruction - Kinnard et al. 2011
Sea ice albedo feedback - NASA
Polar jet stream - NC State University
Greenland ice sheet surface melt - NASA
Permafrost distribution in the Arctic - GRID-Arendal
Atmospheric methane concentration - NOAA ESRL
Russia plants flag at North Pole - Reuters

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Comments 1 to 50 out of 85:

  1. Neven never fails to amaze me in his broad comprehension of this subject and ability to put it into such well written postings. This post should be required reading for everyone in the world old enough to comprehend it. Can someone please translate this into a few key languages and get this spread to as many blogs around the web as possible!?
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  2. In case any reader still thinks this is within the realms of 'normal' - Alex, in a comment on Neven's Arctic Sea Ice blog, updated Kinnard with 2012 ice extent and posted a link to this image:

    from Kinnard updated with 2012 data

    Quite a worry.
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    Moderator Response: TC: Concern has been expressed privately among SkS authors about the potential for this graph to mislead the unwary. The key concern is that the original graph shows a 40 year running average of mean August extents, which the amended graph compares with the 2012 minimum (to date) extent. That is not an apples to apples comparison. Further discussion can be found below by Kar, Dana, and myself.

    This comment should not be interpreted as indicating we do not appreciate the efforts of Alex, Sou or Kar in preparing and displaying the graphs.
  3. A good overview but a dire outlook, thank you anyway. I missed the connection between vanishing sea ice and a possible weakening of the Thermohaline Circulation with may in turn influence the gulf stream. Or is this out of the question?
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  4. sout @2, in the interests of accuracy, Alex showed a 2012 sea ice extent of just over 4 million km^2, close to its current value. The reconstruction, however, is of August average extent. To compare like with like, we should compare the modern August average extent, which is likely to be around 5 million km^2,or about five dashes above the position shown for 2012 in the graph.
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  5. The events and phenomena described in this thread constitute what I believe are collectively a pivotal point in the whole of humanity's response to human-caused global warming.

    Quite frankly, if this isn't sufficient to move us to an urgent, global, and extreme response to what we're doing to the planet, nothing will. Certainly not until it's far too late.

    And if we don't engage in that immediate response, then the future non-viabilities of our global, technological culture, and of a significant proportion of the biodiversity of the planet besides, are guaranteed.

    Those who have known me for a number of years are probably familiar with my progress toward pessimism over the last two or three. I'm going to stick my neck out now and say that if nothing substantial is achieved around the world in the next 12 months or so, or of things go backwards - for example, if there is a change of government in Australia that results in a removal of a carbon price - then subsequent commentary of the whole subject of climate change will simply be no more fruitful than to speculate on how we best manage our decent back to the stone age... if we're that lucky.
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  6. R.Gates @ 1 - Your wish is our command: I just published the German translation!
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  7. There have been two big science stories already this year that made front pages and led TV news bulletins:

    - the Higgs Boson announcement
    - the Curiousity Rover on Mars

    The Arctic Ice story, which will affect millions on the planet far more that these two, should be the science highlight of the year.

    But it isn't, not to the news media anyway. Even if Arctic Ice Extent falls below 4.0million km^2, as it seems bound to in the next two days, or even if it hits the almost incredible (until now!) 3.5million mark, it seems that major media outlets will keep this story an inside page and not at the top.

    It is dispiriting. The laughable thing (if it was not so serious) is that many deniers I have met on the web think this is still mainly about polar bears.
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    Moderator Response: [DB] Fixed text per request.
  8. Current Arctic sea-ice extent is about 15% below the previous record for this date - for comparison this would be equivalent to the men's 100m record dropping down to approximately 8.18 seconds - but as far as I can see no significant mention of this in the main-stream media and most people are presumably blissfully unaware.
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  9. I recently wrote a post on the various effects of a seasonally ice-free Arctic and came up with precisely the same nine as Neven just mentioned, so I feel pretty good about that.

    1. Arctic ecosystem change/habitat loss
    2. Arctic (human) communities culture/infrastructure loss
    3. Albido change to global energy budget
    4. Permafrost melt acceleration
    5. Methane clathrates destabilisation
    6. Greenland ice sheet melt acceleration
    7. Geo-political tensions over Arctic resources
    8. Exploitation of Arctic fossil hydrocarbon resources feedback
    9. Complex effects on NH wind/weather patterns via polar jetstream effects.

    10. I considered a tenth, namely, a further disruption to the global energy budget from the freeing of the latent heat energy that previously was being used to accomplish the phase transition of ice -> water, though my back of the envelope calculations suggest that this is a much smaller issue than albido change (I’d love to see some reputable work on this topic as I’m far from any kind of expert).

    Now that I think about it a little more, I can think of a further seven issues that neither Neven nor I mentioned. Some of these I’m very tentative about (esp ##15&16).

    11. The release of persistent toxins and heavy metals that had become trapped in the ice.

    12. The opening up of Arctic shipping routes which (a) reduces fuel needs of global shipping by cutting distances (negative feedback) but (b) brings more diesel fuel into the Arctic region, leaving black soot on glaciers (positive feedback). Not sure which is the larger effect.

    13. Reconnection of marine ecosystems previously separated by ice with unpredictable ecosystem changes from invasive species. This is already occurring.

    14. Opening up of Arctic fishing grounds to greater exploitation (and noise pollution).

    15. Potential effects on thermohaline circulation. I haven’t seen any work on this related to seasonal sea ice loss, so I have no idea whether it is significant.

    16. Potential effects on ocean acidification by increasing surface area for atmosphere-ocean gas exchange. Would this make any difference to ocean capacity to act as CO2 sink or rate of acidification? Maybe this is irrelevant. I haven’t seen it mentioned anywhere and is just an idea that came to me.

    17 . Highly visual and difficult to dispute sign of climate change, representing a potential tipping point in public awareness and concern. If we are waiting for that, however, before we make any serious efforts to slash emissions (esp if it doesn’t occur until 2030 or later), we’ll already have so much warming committed that we’ll pretty much be toast. At best, therefore, this point might consolidate public support for massive rapid emissions reductions already underway.
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  10. Tom @ #4, thanks for pointing out the difference between minimum and monthly average extent. I probably should have looked more closely.

    It's still dramatic though, isn't it, even if you lift it up a bit. Wonder what the September monthly average will end up being.
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  11. I posted 2 comments earlier and they've been deleted? Could an admin tell me what I should edit please, as I am new to the actual website but not new to your facebook posts. I think that I am making some good points and they are on-topic!

    I agree with Mustermann, the article doesn't even touch on the effects of the Atantic gyre which the Gulf stream is a part of. It runs on water temperature and density and if it halts it will throw Europe into an ice age as the Gulf stream part of the gyre takes water from West Africa underground (I believe) to the Med where it heats it up by trillions of degrees a day which in turn heats the land mass by 5 degrees which is why, even though we're on the same latitude as Russia or New York, we have a milder climate.
    This should mean that the earth will right herself on her own but I do think that there are things that we should be doing to help her along:

    Abort all plans to drill for oil in the arctic, it should be disturbed as little as possible and if there was a spill the hazardous conditions would make a clean-up extremely difficult, if possible at all because they would be digging very deep and the climate and isolated location would greatly hinder any clean-up.

    Almost all travel by boat should be banned or restricted, especially by those huge ice breakers and by those new fangled arctic tourists who are looking to do what very few people can afford to do. Whales from the Pacific along with a lot of other marine life and organisms are finding their way into the Atlantic and vice-versa.
    We've had Pacific whales here in European waters for the last couple of years. As species have evolved to adapt to their own climate they do not have any immunity to alien species. For example, algae from the Med has migrated to the Red Sea and is threatening its existence, it has also migrated to the Indian Ocean and we do not know of its effects yet nor that of other organisms...

    A possible solution:
    I have said for years that we should be spreading or spraying chalk on all parts of exposed earth in the arctic. Basically, for every inch of land that is exposed, it heats up the land a lot more than the parts covered by ice. It absorbs the sun's energy and dissipates it in the surrounding area which is speeding up the melt. Chalk would be an ideal material as it is non-toxic and it is plentiful.

    (-Snip-)
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    Moderator Response:

    [DB] The earlier comments were moderated out due to exceeding the scope of the topic of this thread (a familiarity with this site's Comments Policy, also used on its FB page, is suggested).

    In the interest of furthering discussion, those individual portions of this comment also fitting that description were moderated out.

    It is left as an exercise to readership to address the other remaining portions of this comment.

  12. Several things have depressed me in the last few days.

    First was the smashing of the sea ice extent record in grand style -- though in the last few weeks it became clear it was going to go.

    The next was the conference which began in Alaska, yesterday. When I heard some of the speakers talking on the live feed my jaw dropped. Talk was almost totally about the opportunities presented by an ice-free Arctic, from the development of oil, gas and mineral resources, to the increase in tourism and opening of new shipping routes. Hardly a word about negative consequences; just a few asides about how to manage 'change' sensitively. No climate change denial here!

    Then this morning I opened the Sunday Times to see an article about the sea loss by Jonathan Leake, their science correspondent. OK, it started well enough by providing graphs and quotes from key Arctic scientists and NGOs, but then ended with this blatant 'false balance' (taking up about 25% of the copy) ...
    "Some scientists are more cautious and point out that satellite imaging of the Arctic -- the main way of measuring coverage -- only began in 1978.

    One idea is that the icecap may shrink and grow naturally over decades. Such cycles are common in ocean science, so the recent melt may just be the first time we have monitored it.

    Professor John Christy director of the Earth System Science Centre at the University of Alabama in Huntsville, said the Arctic had indeed warmed, but there was also anecdotal and other evidence suggesting similar melts from 1938-43 and on other occasions.

    "Climate change is a murky science", he said. "To some it's an easy answer to say it's due to extra green house gasses. To the rest of us, separating natural variability from human impacts remains a wicked problem."
    My blood boils: "some say...", "...but to the rest of us...". Yeh, right, 'the rest of you' -- a tiny, tiny minority in denial. And that thought is left in the minds of the influential people who read, arguably, the UK's most prestigious Sunday paper. [Sorry I can't provide a link, it's behind a paywall].
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  13. BaerbelW @ 6 - Excellent! Thank You...

    John Russell said: "When I heard some of the speakers talking on the live feed my jaw dropped. Talk was almost totally about the opportunities presented by an ice-free Arctic."

    And there's the heart of the matter. Many don't see the pending Dragon King regime change coming to the global climate that has begun in the Arctic. The are taking a business-as-usual approach, believing that nothing is about to change, and life will go on as it has, but now with "greater opportunity" for getting at the fossil fuels in the Arctic. This is akin to the Thanksgiving Turkey who has been well fed for many years prior to the day before Thanksgiving, and assumes this trend will continue forever. Of course, the Turkey's assumption would be wrong as that Turkey's Dragon King event is soon to hit. But This is a conservative mind-set. Not conservative in the political sense, but in the psychological sense that such a mind-set is always the last to even think that change could come and come swiftly.

    Think about how amazing it is that even just in the 2007 IPCC report, no thought was even given to the possibility of an ice-free Arctic by 2020-- yet that is entirely possible now, perhaps even probable. What should be happening right now are international efforts to prepare to figure out how we are going to feed 7+ billion humans if the NH weather (where the bulk of the food is grown) continues become more disrupted as described by Dr. Francis at Rutgers.

    And we haven't even begun to see true force of the methane releases that are inevitably coming. In short...this story of the dramatic loss of sea ice in the Arctic this year should be the top science story.
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  14. I agree with you John, some people always think about making a fast buck rather than ensuring that life as we know it, or just life, carries on on this planet. As shoyemore siad 'The Arctic Ice story, which will affect millions on the planet far more that these two, should be the science highlight of the year.'
    I would also like to clarify one of my points about the albedo effect: Dry sand has a higher effect than sand and less than snow. In the arctic, very little snow falls as it is usually too cold and there is very little wind to throw that snow around to maximise the effect.
    I say usually, because there has actually been more rain of late in the arctic, speeding up the melt.
    Interesting articles here: http://www.sciencedaily.com/releases/2008/11/081107072003.htm
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  15. "...it heats it up by trillions of degrees a day..."
    You should rethink your phraseology used in this bit; as it stands it is very wrong...on many levels.
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  16. Leake has a certain track-record along these lines, John. Due skepticism and all that, as in the final sentence of my post on Patrick Moore the other day. But the trouble is that people don't always think skeptically.
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  17. For a modest (but possibly useful) Arctic geoengineering effort, see Ice911.

    Read carefully, including people involved, some of whom I see occasionally, including Leslie. Steve Schneider was an advisor before his death.
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  18. Dear admin, I have just seen your reply, how is the albedo effect off-topic?! In the third paragraph it states '... the role Arctic sea ice plays as a reflector of solar energy', which is the albedo effect...
    Daniel, in my deleted post I did say I would appreciate feedback. Please explain where I am wrong as I have heard this amount used in more than one publication and although I found the figure mindblowing at first, it seems reasonable that it would take that much energy to heat up the land mass of Europe. (
    Jonh Mashley, I am finding it difficult to find what the project actually is on the link that you have provided so could you please elaborate?
    I was thinking about geoengineering before the term was even coined, but i thought that the UN had ordered a halt on all geoengineering projects a couple of years ago?
    Admin, please bear with me, I'm not a scientist, nor a climate change denier, I want to learn and understand and am actually glad to speak to people who are knowledgeable in this area...
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    Moderator Response: [DB] If you wish to pursue a discussion on desert albedo changes, please post a comment on the Skeptic Argument The albedo effect and global warming. This thread is about Why Arctic sea ice shouldn't leave anyone cold
  19. Just thinking about the 'opportunities' an ice-free Arctic presents: it's a bit like falling off a cliff and exclaiming, "At last! I've always wanted to fly!"

    What worries me most is that once the countries bordering the Arctic start exploiting their new territories, they'll come to think climate change is a net benefit and then become a force to resist emissions reduction. This really could create fierce new planetary divisions: the low versus the high latitudes.
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  20. @ sout # 10. It's a little hard to say, given the fairly noisy and weather driven nature of the sea ice minimum. However, given the increased melt rate (daily falls of more than 100 thousand have occurred regularly this month) and an extent already below 07's lowest; it'll be, at best, 600 K square kilometers less than the 2007 September average.

    As of Aug 26th, the current extent is roughly 4.05 M SqKm, and I expect that by September 01 that will have reached at least 3.7 - 3.8, looking at the daily figures provided by the IJIS (http://www.ijis.iarc.uaf.edu/seaice/extent/plot.csv).

    It's not improbable that the annual minimum will drop or below 3.5 M Km - given that most years a further 200 -300 K is lost in September itself. Thus a projected September average of 3.6 - 7 ish is at this stage hardly outlandish, and may yet prove a conservative estimate.

    For it to be even as high as 3.8 it would probably need to plateau by the end of the week, which doesn't seem likely at this stage.
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  21. Does anyone have any ready references to Christy's allegations about the arctic 1939-43? I'm not sure where I'd start looking and it helps to be prepared.

    Thanks
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    Moderator Response: [DB] There is a compendium of links under the Christy Crocks button on the left side of every SkS page.
  22. RealClimate has just posted this update from NSIDC Arctic Sea ice Extent:


    [Source]

    Note the use of absolute extent. Shades of Brody, 2013 will need a taller graphic...
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  23. John @12,

    I share your feelings.

    That quote you provided is an unsubstantiated and blatantly false statement by Dr. Christy. We now have another Christy Crock to add to the long list. Dr. Christy is entitled to his own (misguided) opinions, but not his own facts. I have a pretty good idea what Christy is doing here, but the comments policy prevents me from being perfectly candid. I’ll let readers draw their own conclusions.

    By the "rest of us", Christy is in fact referring to certain fringe and contrarian elements such as himself who represent 2-3% of climate scientists. Christy's assertions are also at odds with those scientists who specialize in Arctic sea ice (e.g., Polyak et al. 2010; Walsh and Chapman 2001). To wit,



    [Source]

    As the above figure shows, Walsh and Chapman found no evidence whatsoever of a reduction in total Arctic sea ice in the thirties or forties that came even remotely close to the scary minima in total Arctic sea ice that we are now experiencing. Not to mention that previous minima (as found by Kinnard et al) were transient, what we are experiencing now is a systematic and accelerating downward trend in total Arctic sea ice at a time when temperatures over the northern high latitudes should be decreasing because of a reduction incoming solar radiation.

    I will have more to write on this soon, Christy should be taken down hard for yet again making such blatantly false and unsubstantiated statements to the media. This is shameful, irresponsible and unprofessional behaviour for someone of his standing IMO.
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  24. You might want to update the Christy Crocks to include the allegation on arctic ice 1938-43. I sure didn't see it on the main page of quotes, and it was certainly new to me. Albatross' post was exactly what I was looking for.
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  25. @Dave 123

    The only "anecdotal or other evidence" I can find to back up Christy's assertion -- and I can find a reference to Lindzen saying the something similar -- is this letter to Nature in 1996. However, I can find loads to support the view that the melt we're witnessing is unprecedented in historical time frames. Try here, here and here.
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  26. @Albatross

    You might find the links I provided in my comment, immediately above, useful for the Christy debunk.

    By 'historical times' I, of course, meant 'recorded history'.
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  27. Changing the thermohaline current is scary but unlikely. There are 3 main reason why we should be concerned with AGW: food, food, and food. Corn dies on the stalk when it's exposed to temps above 112. This summer it hit that and more in Kansas, the heart of the agricultural production in the US. And corn died. Pronto. The next bad heat wave will be worse. Soon, and for the rest of our lives, it will be much worse still.

    Not to play the Panic Card, but at this point, what exactly would it take to get politicians off their duffs?
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  28. Neven has now posted an extended version of this article on his Arctic Sea Ice Blog:
    Why Arctic sea ice shouldn't leave anyone cold
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  29. (Continuing the numbering of points)
    18. (containing likely fruitless original research) While it's pretty clear that seasonally ice-free arctic messes up the polar jet stream with all sorts of weather irregularities in the temperate zones, the effect further south is not that clear. one might think there would be summer time continental high pressure areas (as the lows are in the arctic) which gives rise to the wet oceans/dry continents -argument that has been referred in some scientific literature for a long time. No doubt the arctic clouds will come southwards but how far they'll get? These highs in turn might effect the routes of tropical storms so (comes to mind) eastward hurricanes in Atlantic might become the norm (could there be two jet streams still in NH but the other one is new and not polar?).

    With the extra energy in NH (via the albedo effect), will these consequent changes in weather patterns propagate even to the equator pushing the intertropical convergence zone elsewhere (and north or south, does it matter?) Will there be more doubled ITCZs than previously and what does that mean?

    Anyway it's pretty clear the extra energy finds its way to the southern hemisphere eventually (thermohaline circulation at last) and starts warming up the waters there too. In summary, it looks to me like the countdown to acceleration of GIS or WAIS -melt ends with the disappearance of a stable polar vortex/summer ice in NH.

    (gotta stop, seeing tropical storms in the British channel and that's not good for clear thinkin ;-))

    jyyh @ +20 ASL
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  30. The St. Roch, a Canadian ice breaker, made its passage of the North West Passage in 1943. This SKS post describes that passage. Some deniers claim that since the St. Roch was able to make the passage it means there was no ice. This is clearly not true and anyone who checks the written record can see that it is false. Obviously, Cristy does not care if it is true or not. This denier meme has not been used much lately, but was more popular a couple of years ago.
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  31. Jeffrey Davis @ 27

    "what exactly would it take to get politicians off their duffs?"

    Seeing as the politicians, media and large portions of the general public are effectively giving the finger to the scientific community and its opinions, how about a global day of scientific inaction? That might get some people to at least ask what the fuss is all about. It might even get some politicians interested, well, the ones who are not to be bought by campaign donations, anyway.
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  32. John Russel @25 - great links, thanks. However, the 1996 Nature letter refers to Antarctic sea ice. I don't suppose you can find the article quoting Christy anywhere, or perhaps could scan your paper version for us?

    michael sweet @30 - thanks for that link too. I wonder if the St. Roch passage is the 'anecdotal evidence' Christy refers to.
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  33. Although this ice melt is a worry, so was the Texas 2011 drought, incredible, as was the Russian drought, as was the March North American heatwave (records brocken by 20-30C), as was the Amazon drought 2010 and so on, so why should this make people less likely to withdraw from denial?

    Considering the lagged heating system the earth is and the extra energy imbalance the sea ice melt, NH early snow melt and Greenland Ice sheet albedo shift due to dark ice under the snow induce, how much more additional carbon emissions feels safe?

    Does 2C feel safe considering what is happening already?

    1.5C, 1C?

    The quickest and easiest way to stop emissions to stop using power, or is that too much of a challenge?
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  34. I was looking around for info on another topic when i came across this blog which is the scariest scenario iv'e come across for a warming arctic ocean, a short extract
    Striping of Oxygen from the Oceans
    Another disquieting effect of methane release is related to what happens when you bubble a gas through a liquid. The surface of each bubble acts as a semi-permeable membrane. Gases diffuse across the surface of the bubble in proportion to the difference in their concentration on either side of the 'membrane'. In the case of a bubble of methane, the oxygen from the water diffuses into the bubble and is carried to the surface of the ocean. In other words, an extensive evolution of methane gas from the ocean bottom would scrub the oxygen out of the water. Methane which remains dissolved in the water reacts with the oxygen, depleting it and forming Carbon dioxide. Not only do you have a depletion of oxygen but also an acidification of the water from the Carbon dioxide. If this happens, all water breathing life, may die and the Arctic will become an anaerobic cess pool. This adds a further dimension. All the dead sea life, under anaerobic conditions, will also liberate methane as it breaks down not to mention oxides of nitrogen and sulphur. There is also the possibility that under deep ocean pressure, methane will dissolve in large amounts in the water and as currents bring this water closer to the surface, the methane may start to bubble out, causing an upwelling like an air lift, far from the original source of the methane. This will pull more methane rich water upwards to release its burden of methane suddenly into the atmosphere.

    http://mtkass.blogspot.co.nz/2008/07/arctic-melting-no-problem.html
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  35. Take a look at the opening paragraph of the Toronto Changing Atmosphere: Implications for Global Security conference held in 1988. The conference statement is here. Scientists who attended explained that 95% of their colleagues would not hesitate to sign that. The first sentence:

    "Humanity is conducting an unintended, uncontrolled, globally pervasive experiment whose ultimate consequences could be second only to a global nuclear war"

    The conference was a four day effort for 400 high level delegates assigned the task of coming up with that statement. What could 400 delegates from 40 countries agree the threat of climate change represented?

    I remember a back room conversation between Digby McClaren, then President of the Royal Society of Canada and a delegate I didn't recognize. McClaren cut the man off in the middle of his statement about how things might not be so bad. "What about the Vostok Core?" is all he said. He expressed this thought with feeling - he sounded like a navigator on a space ship addressing the captain who had just committed the ship to hit a star.

    No one stood to contest McClaren.

    With all due respect to those saying the latest data from the Arctic is so bad everyone should take it seriously and the world and civilization will change, I say, the same thing was said about this or that dataset back then.

    The Vostok core data should have been enough to convince civilization it needed to stabilize the composition of the atmosphere.

    But it didn't.

    If you went out into politics, back then, and tried to make a case that people should vote for people who would implemenet policy to stabilize the composition of the atmosphere and return it to the preindustrial you were regarded by most people as insane. This is what I did. I had my own little version of a slide show like Gore's and I would appear wherever I could find an audience.

    I felt then the way many are expressing themselves in the comments here now.

    It was obviously too late for civilization to save itself back then. What we faced back then was greater change than what the planet had experienced in going from an ice age to an interglacial only the change was further warming from an interglacial, and what was most worrying was the projected rate. This was going to go at a speed far faster than almost anything in the paleo record. You have to think about the asteroid hit that took out the dinosaurs when you wonder about change that was faster and you have to think that the climate change prospect we faced in 1988 was going to be more far reaching and much longer lasting. And especially what we faced then was a civilization so deeply committed to using fossil fuels it could not think straight.

    This is still what we face now. Every aspect of the situation is more grave today, but in essence, it is the same situation.

    So it can be faced. You can understand what is happening and still find power to act on any given day.

    So don't be so downhearted. My grandmother used to say that to me sometimes. So what if the latest data streaming in from the Arctic is bad news.

    By now what we want is the worst news possible.

    The main problem I see with the latest Arctic data is the news isn't bad enough. The morons are ignoring it. They're drooling over the vast region that is opening up where they're going to find more oil and gas.
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  36. Michael Sweet @ n

    New threads pop up and die down quickly here, and you appear and vanish almost like a virtual particle. Anyway I left you a message in the teaching thread:

    http://www.skepticalscience.com/Teaching-Climate-Change-Schools.html
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  37. johnm33 @34, I cannot help feel that you are buying trouble here. The upper ocean concentrations of various gasses maintain an equilibrium partial vapour pressure with the atmosphere on a very short (about one year) time scale, so that any "oxygen scrubbing" by methane bubbles would be quickly compensated for by increased absorption of oxygen by the ocean at the surface. Indeed, with greater exposed surface due to reduced sea ice cover, the return to equilibrium should be even quicker.

    There will be a reduction of dissolved oxygen as the planet warms, but that is because warmer water holds less gas. However, the amount of that reduction is, I believe, too small to be a significant threat to marine life.
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  38. "A 2008 study found that a period of abrupt sea-ice loss could lead to rapid soil thaw, as far as 900 miles inland."

    Has anyone taken into consideration the fact that the quicker the permafrost warms, the higher the metabolic rate of the Methanogens becomes?

    With a higher metabolism there will be a higher rate of methane production. Would anyone know how much of an increase in methane production we'd get per degree of increasing soil temperature?

    Due to the lethargy of micro-organisms in the cold there should be an enormous increase in metabolism from, let's say, 40F soil to 60F soil.

    Another positive feedback loop?
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  39. In response to suggestions that 'we' don't know about the arctic sea ice before satellites, it's pointed out that there were ships.

    Ships keep logs - and very good logs.

    NSIDC has some good compilations of Nordic ice edge from March through August for the period 1750-2002. It's not complete for obvious reasons, but if there is impenetrable ice down to a certain latitude then there's likely to be ice north of that latitude. Files are in different formats, even jpeg so you can visualise the edge.

    http://nsidc.org/data/docs/noaa/g02169_nordic_sea_ice/
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  40. If I get banned I will assume you're all climate change deniers! Joke. It's bank holiday here in the UK and it's 7.20 am. I fink the admins have gone to sleep so I will copy n paste ur comments and read them when I'm sober, I love all the viewpoints. Is there a page on 'ere where u can discuss general interaction of ecosystem in one place?
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  41. BTW I don't understand the abbreviations and therefore can't follow the threads properly. Please enlighten me and refer to the whole words initially at least, TYVM.
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  42. Tom Curtis @37 I dont' find your comment very reassuring, if the equilibrium is re-established over the time period you claim how do they 'breathe' in the meantime?
    https://sites.google.com/site/apocalypse4realmethane2012/home/2012-vs-2011-airs-ch4-359-hpa
    and clearly the [arctic] oceans warming is provoking a vast increase in methane release.[and not just in the ocean]
    If you have the time you should read the whole post i took the extract from and linked to, it raises many issues, has been recently added to, and assuming his profile is true has much relevent expertise.
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  43. "Can someone please translate this into a few key languages and get this spread to as many blogs around the web as possible!? "

    A Dutch version is on my blog: http://klimaatverandering.wordpress.com/2012/08/26/waarom-arctisch-zee-ijs-niemand-koud-zou-moeten-laten/
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  44. What about the Gulf Stream? I understand that it would be in danger of collapsing if there is too much fresh water introduced into the Atlantic. The consequences to European agriculture would be immense if the Gulf Stream no longer brought warm water to the north of Europe.
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  45. John while there is reason to believe that circulation changes may result in a slowing of the AMOC (of which the Gulf Stream is a part), there doesn't appear to be enough evidence to show that a shutdown is in order.

    For a detailed discussion of this, see here:
    The Last Interglacial Part Four - Oceanic Influences
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  46. curtis@4 commenting sout@2 are suggesting that the curve should be more like this:



    Still clear, bad and not a trend anyone would like.
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    Moderator Response: TC: Concern has been expressed privately among SkS authors about the potential for this graph to mislead the unwary. The key concern is that the original graph shows a 40 year running average of mean August extents, which the amended graph compares with the estimated 2012 August mean extent. That is not an apples to apples comparison. Further discussion can be found below by Dana, and myself.

    This comment should not be interpreted as indicating we do not appreciate the efforts of Alex, Sou or Kar in preparing and displaying the graphs.
  47. Zachariae Ice Stream is one place that needs much more cold. Dan Bailey, our prediction is still valid.
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  48. Anytime you're ready we can do a standalone post on the ZIS, Mauri. The big league hitters like Zacharaiae deserve some attention all their own.
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  49. Much discussion about this year's trends in sea ice extent and area on line. I've seen several comments mentioning how the extent continues to drop, even though by this time of year we usually start to see a reversal (or at least a slowing of melt).

    I followed the links on Neven's blog to grab the data from IARC-JAXA, and created the following graph. It shows the daily change in sea ice extent. I've smoothed it with a five-day running mean, but a couple of caveats:

    - I didn't bother dealing with the end-of-year wrap, so days 1-5 and 360-365 aren't quite right
    - I didn't bother accounting for Feb. 29 in leap years
    - nothing special was done to the last few days of 2012, so the running mean actually runs on past today (August 27) because the means for August 28-31 already have one value that they will need. Thus, the last few points for 2012 actually are for fewer than 5 days, and devolve into a single day's value, with the last one being the real value for today (plotted as it if is the August 27-31 running mean). This tends to accentuate the current decrease.

    Anyway, here is the graph:

    Image and video hosting by TinyPic

    All I can say is that the current melt pattern (over the past week) certainly seems to be outside the bounds of experience. "Normal" doesn't live here any more.
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  50. A point of clarification on the Kinnard graphic. It extends to 2008, thus including the 2007 minimum, and thus does not need to be extended much further down to incorporate data up to present. The values are not as low as one might expect, no doubt because of the 40-year lowpass filter being applied. I'd say the unedited version of the graphic is a pretty reasonable representation even up to present.
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