Summer ice in the arctic has recovered

This is just one of dozens of responses to common climate change denial arguments, which can all be found at How to Talk to a Climate Sceptic.


Objection:

Sea ice at the north pole recovered a whopping 9.4% from 2007 to 2008 despite the doom and gloom predictions of the alarmists. Yet another wheel falls off the global warming bandwagon.

Answer:

It is true that the minimum summer ice extent in the arctic ocean in 2008 was 9.4% higher than the minimun in 2007. But calling this a recovery is simply not justifiable, not even by a long shot. Firstly, at 4.52 million square kilometers, this measurement is 2.24 million square kilometers below the average minimum observed since 1979 when accurate satellite observations began, so we are nowhere near getting back to normal levels of ice cover. (Source: NSIDC) Secondly, year to year flucuations are very large and simply reflect the chaotic nature of weather, the change over a single year does not say anything meaningful about climate trends.

So what is the trend?

(image courtesy of NSIDC)

There are several things worth noting that we can see from this image. Not only is 2008 below the average as noted above, it fell well below the downward trend line, the fourth year in a row to do so. So hardly showing sings of recovery, this year is consistent with an accelerating ice loss. We can also see that an almost 10% jump from one year to the next is not unprecedented. The jump up from 1995 to 1996 was even larger, nearly twice so. The differences between 1989-1990, 1994-1995, 2001-2002, and 2006-2007 all were larger as well than the difference between 2007 and 2008.

We can also see that 2007 was really an exceptional record setter and aside from that year, 2008 is lower than any other. This is hardly the "warming is over" news the climate denialist organisations and websites have been proclaiming or at least implying.

So that’s what has happened, but what were the "alarmist" expectations? It is true that a small number of media reports quoted people saying there might be another record this year, maybe even total ice loss (can anyone show me an actual prediction?), it makes a nice sensational headline after all, but if you look to climate science you see a predictive failure in precisely the opposite direction. No research papers from scientists in the field have been predicting ice loss at the rate it has been happening. Checking in the IPCC report from 2007, in the Summary for Policymakers[PDF] we find this on page 15:

"In some projections, arctic late-summer sea ice disappears almost entirely by the latter part of the 21st century."

This is nowhere near a prediction of total summer ice loss by 2008 and it is looking more and more like it will be very wrong by being too conservative. This is not the hallmark of an "alarmist"!

So, I guess the reality is that 2008’s summer arctic ice extent observation is not a wheel off the GW bandwagon, it is one more nail in the coffin of denialism.


This is just one of dozens of responses to common climate change denial arguments, which can all be found at How to Talk to a Climate Sceptic.


“Summer ice in the arctic has recovered” is also posted on the Grist website, where additional comments can be found, though the author, Coby Beck, does not monitor or respond there.

108 thoughts on “Summer ice in the arctic has recovered

  1. Coby,

    Read your article and then read the discussion, then checked the sources. NSIDC says that the mean was not 7.7 million sq km. They show that the 1979 – 2000 mean was 15.7 million sq km. The trend was -2.7 +/-0.7 percent per decade not -8.7 percent you listed. This is found at http://nsidc.org/data/seaice_index/images/n_plot_hires.png which shows that the Arctic has been recovering from the 2007 low. The Arctic sea ice is within one standard deviation of the mean.

    When Arctic sea ice recovery is considered part of the global sea ice extent, we are either at or above the global mean. This can be seen at http://nsidc.org/data/seaice_index/images/daily_images/N_timeseries.png . So, the trends are not as bad as you depict, further, recent measurements show that the sea ice is thicker than previously though.

    Oh and 1/3 or more of Arctic warming was due to carbon black (pollution) from Europe and Asia per a UC-Irvine stude a few years back.

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  2. Vernon –

    They show that the 1979 – 2000 mean was 15.7 million sq km. The trend was -2.7 +/-0.7 percent per decade not -8.7 percent you listed.

    You’re referencing the data for April ’09. Coby’s post is showing the data for August last year. These graphs are separated by month.
    “This graph plots ice extent anomalies (the difference in the extent for the month minus the mean extent for that month over 1979-2000) for the most recent complete month.”

    …which shows that the Arctic has been recovering from the 2007 low.

    Using the same logic, we can say that the ice in 1997,1998 and 1999 recovered from the “low” of 1996. But, the long-term trend continued downward. I’ll repeat what you seem unable to comprehend, no one expects monotonically decreasing ice (or monotonically increasing temperatures). You’re missing the forest for the trees.

    When Arctic sea ice recovery is considered part of the global sea ice extent, we are either at or above the global mean.

    I think you’re interpretting this graph wrong. The mean is the gray line. The 2009 data (blue) is below this line for all points by varying amounts (but still above the 2007 data).

    Oh and 1/3 or more of Arctic warming was due to carbon black (pollution) from Europe and Asia per a UC-Irvine stude a few years back.

    It’s unclear what point you’re trying to make here. Artic warming has been significantly higher than the global average, so it stands to reason there are more factors at play here. Also, this supports the contention that global warming is due to human industrial activity, so I struggle to see how you think this supports your conclusion that “the arguments for man-made warming are falling apart” posted in another thread.

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  3. Vernon, the difference in your average extent and your trend is because as Adam points out you are looking at April values, I was looking at August values. This is actually not what I meant to do, I was meaning to look at the annual minimums. This will only be off by about 2 weeks though so I would not expect any substantial difference. Arctic sea ice reaches its minimum extent in mid September.

    The annual minimum is a much more meaningful data point than the April value.

    Your second point about being near the 79-00 mean is yet another appeal to weather to disprove a climate trend. I will not bother to say this again: individual year, and even more so, individual month values represent weather and do not by themselves contain one iota of information about climate trends.

    Trying to argue that the sea ice in the arctic is not shrinking is the essence of denialism and that is why very few intelligent people bother to take those arguments seriously.

    You are correct about black carbon and this should be emphasized more. James Hansen has been arguing for nearly a decade that we could do a lot to mitigate GW right now by reducing that kind of pollution while we try to tackle the much harder problem of CO2 emissions.

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  4. Passage deleted by blog admin

    So just to make things clear we have 30 years of sat data on ice so according to you this past 30 years is the be all and end all of ice extent.

    [Well, we were discussing the available satellite data. Just a couple of comments up thread, you thought a single month in a single year was sufficient to discern a climatic trend. Now you are complaining that 30 years is too little? This is why I don’t believe your interest in the science is at all sincere, you change tactics and arguments and data sets soley to evade a conclusion you don’t like. That is not what skepticism is.

    I deleted the first part and the remainder of this comment because it is all abuse and no content. Please be civil, or at least insert some reason in between your invectives.

    – coby]

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  5. Did not take long for the lap dog to start yapping did it.

    How come when you lot say “the Arctic is melting fasterthan ever, faster than ever i tells ya” its all caused by global warming.

    But when i present factual evidence to show the exact opposite i get “aw thats just weather your to stupid to know the difference”

    I will tell you why this is Adam because you are full of crap. You add nothing to the scientific debate you are simply someone who like to argue. You have not added one comment that is founded in science since your first post here.

    Here is an article that shows the sea ice is in fact in recovery now i am sure you will discredit the web site or the author but i bet you all the tea in china you will not go near the science. Not one of you will do that.

    Click to access AARI_PREDICTS_ARCTIC_COOLING.pdf

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  6. Crakar, see replies inline for comment 54, and please refrain from the gratuitous insults.

    How come when you lot say “the Arctic is melting fasterthan ever, faster than ever i tells ya” its all caused by global warming.

    Because this is what the available evidence very clearly indicates.

    But when i present factual evidence to show the exact opposite i get “aw thats just weather your to stupid to know the difference”

    Because the fact you presented was just weather. I have no idea if you are unable or just unwilling to understand the difference. Well, I do prefer to assume that you are unwilling, because it really is a very simple concept.

    I have looked at the PDF you pointed to, and as they are also unable or unwilling to understand the difference between short term noise and a long term trend, there is clearly nothing to take seriously in there.

    Crakar, humor me while I try one last time. Look at the graph they present to show sea ice has “bottomed out”. Compare the “bottom” in 2007 to the following years: 1984, 1990, 1995. They could have presented the same case in 1985, 1991, and 1996 as they present now, and time has shown they would have been 0 for 3. The argument is wrong every time. Why do you think the argument is valid in 2009?

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  7. Coby you said

    “I have looked at the PDF you pointed to, and as they are also unable or unwilling to understand the difference between short term noise and a long term trend, there is clearly nothing to take seriously in there.”

    The PDF states

    “The most competent polar scientific organization, Arctic and Antarctic Research Institute (AARI) in St. Petersburg, Russia”

    and

    “The authors showed that Arctic climate change is natural in origin and several orders of magnitude greater than the level of anthropogenic impact on the climate.”

    So are you saying that you are a higher authority than the AARI? They claim climate change in the arctic is natural you say it is not. Sorry but i will accept thier findings rather than yours.

    You said

    “Compare the “bottom” in 2007 to the following years: 1984, 1990, 1995. They could have presented the same case in 1985, 1991, and 1996 as they present now, and time has shown they would have been 0 for 3. The argument is wrong every time. Why do you think the argument is valid in 2009?”

    I fail to see your point since 2007, 08 and 09 summer melts have been less so yes it “bottomed” perse in 07. If your point is that since 79 there has been a gradual fall in ice then the eventual bottom maybe still ahead of us, then yes i agree it will be interesting how ice there is in September. But as the PDF states this is all due to natural climate variation and not increases of CO2 in the atmosphere.

    Mind you the graphs do paint a scary picture dont they when in fact from the PDF they state;

    “It has returned to very near the 1979-2000 year average (NSIDC). Had NSIDC used the entire period of record as their base period (1979-2008), we would be at or above the average.”

    So from this we can see that the overall trend (79-08 or 30 years) is infact flat, agreed?

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  8. So are you saying that you are a higher authority than the AARI?

    I see, so now argument from authority is just fine with you? Your inconsistency is the most consistent aspect of your comments. The NSIDC completely disagrees with AARI, do let us know why you prefer to shop Russian all of a sudden.

    This is textbook denialism, cite and argue anything that seems to agree with your prefered conclusion, ignore and deny everything else, change tactics midstream even if it contradicts your own previous points, it is an exercise in futility.

    We’ve been through the rest of your comment before, not interested any more. I only respond so that lurkers and the archives have everything they need to understand the various errors and fallacies you employ, and that job is done.

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  9. Coby states:
    [ Look at the graph they present to show sea ice has “bottomed out”. Compare the “bottom” in 2007 to the following years: 1984, 1990, 1995. They could have presented the same case in 1985, 1991, and 1996 as they present now, and time has shown they would have been 0 for 3. The argument is wrong every time. Why do you think the argument is valid in 2009? ]

    From my position Coby is correct. And his last question is what we are trying to answer. My answer is, I don’t know. The models are trying to predict it. And as time goes forward, weather becomes climate. So we shall observe the reality as it unfolds. Time will test the model and we shall know the answer, but not until then.

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  10. Coby and the soft shoe shuffle,

    Is the Arctic melting due to AGW? If so rather than make these claims based on a belief system show me the empirical evidence that shows it.

    And while your at it show me the empirical evidence as to why AGW makes the Antarctic colder so its ice extent has increased.

    We have 30 years of data showing Arctic ice extent, 30 years of a +PDO, multiple strong el ninos and the most active sun in the past 1000 years but ignore that its all caused by AGW.

    By the way you often quote the Vostok ice cores so what is wrong with russian data ?

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  11. Regarding comment #62,
    here is a study from NASA which clearly states that CO2 plays no role in arctic clmate

    Of course the NASA study cited by that article says no such thing. Nor does the article.

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  12. Regarding comment #63

    And i quote for the article link in comment #62 “New research from NASA suggests that the Arctic warming trend seen in recent decades has indeed resulted from human activities: but not, as is widely assumed at present, those leading to carbon dioxide emissions. Rather, Arctic warming has been caused in large part by laws introduced to improve air quality and fight acid rain.”

    and

    Dr Drew Shindell of NASA’s Goddard Institute of Space Studies has led a new study which indicates that much of the general upward trend in temperatures since the 1970s – particularly in the Arctic – may have resulted from changes in levels of solid “aerosol” particles in the atmosphere, rather than elevated CO2. Arctic temperatures are of particular concern to those worried about the effects of global warming, as a melting of the ice cap could lead to disastrous rises in sea level – of a sort which might burst the Thames Barrier and flood London, for instance.”

    Now you knew it said this Coby but yet still denied it. So in summary you dispute the AARI because we cant trust the Russians unless its the Vostoks ice cores (re used by yourself and IPCC as a source of data) and then you religiously ignore the written word of NASA GISS and just pretend its not written. Are you aware of just how deep your denial is Coby?

    You cannot simply reject reality and substitute it with your own, well you can in computer models of course not in the real world.

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  13. Crakar, there is a big difference between “CO2 plays no role” and “much of the general upward trend in temperatures … may have resulted from changes in levels of solid “aerosol” particles in the atmosphere, rather than elevated CO2″

    This is not a controversial finding, James Hansen has been identifying aerosols and black carbon (soot) as a major contributor to arctic warming for over a decade.

    No one has ever claimed that CO2 alone controls climate trends.

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  14. Coby,

    You do realize that all flap about the melting of the Arctic is red herring. The truth is that the Arctic is not the warmest it has been in the last 1000 years, it is not even the warmest it has been in the last 100 years. If it was warmer in the past, then may be, picking the current 30 year period with satellite coverage is pretty meaningless.

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  15. Paul and crakar

    Thanks for the link. Tell me, did you read the words at the links or just look at the pretty pictures? If you did read them, can you tell what you think of these quotes (near the bottom of the page):

    “…The late date of the maximum extent, though of special interest this year, is unlikely to have an impact on summer ice extent. The ice that formed late in the season is thin, and will melt quickly when temperatures rise…”

    “…However, this replenishment consists primarily of younger, two- to three-year-old multiyear ice; the oldest, and thickest multiyear ice has continued to decline…”

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  16. All new ice is thin, it has to start somewhere. You complain about global warming, err “climate change”, point to the low ice extent as proof, then run away from it when it changes.

    Either it is a useful metric to discuss or it’s not.

    And did you read that the most likely cause of ice loss in the recent years has been wind blowing it out of the arctic more than usual? Or did you simply forget to mention that?

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  17. “You complain about global warming, err “climate change”, point to the low ice extent as proof, then run away from it when it changes.” – PaulinMI

    As useful as sea ice extent is as a measurement, it’s only two dimensional, it tells us nothing about sea ice thickness i.e volume:

    The prognosis is still terminal for the Arctic summer sea ice.

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  18. With this in mind is anyone prepared to make a prediction as to what the minimum sea ice extent will be come September?

    And let me guess: If we don’t get it within a cubic meter you will dance in glee at having again “refuted” AGW–sort of like your faux IPCC 10-year prediction.

    Nice try, Crakar.

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  19. “sort of like your faux IPCC 10-year prediction.”

    I notice crakar has seemingly ‘forgotten’ that he still has questions to answer on that front.

    I won’t hold my breath though…

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  20. I was planning on being a little more lenient than that Skip.

    From what i have read the Arctic sea ice extent depends heavily on the AO which in turn is dependant on the NAO, the NAO has been in +ve phase since around 1976 (three years before sats started looking)on current trends of NAO i would guess that the summer extent will be higher than the previous years. If i were to give a figure i would say somewhere around 6.5 to 7 mil square K’s (about 2003 levels).

    Its a shame warmers are so childish.

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  21. Amazing.

    Since you won’t answer the direct question of what hypothetical evidence it would take to convince that AGW is both real and potentially threatening, here’s another direct question:

    In the history of this forum, who has been more “childish”–you or me?

    Its really simple either-or. I suspect you’ll dodge it.

    And here’s another one while you’re at it: How can you measure “intellectual dishonesty”–I mean, what the are hallmarks?

    Just curious, although I also expect no answer.

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  22. Hypothetical evidence is evidence that does not exist, how could i make a decision based on this?

    The childish comment should be attributed to all those that posted not just you Skip. I asked a question, a simple question really what do you predict the ice extent to be by Sept. However due to your very own narrative and this idea that your faith is being constantly challenged you did not respond to my question but simply took this as an opportunity to post some utter crap.

    I do not know how to measure intellectual dishonesty Skip, why dont you take the measurements and tell me the results.

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  23. crakar. What gives you the right to expect straight answers to your questions when you fail to answer questions posed to you, preferring to obfuscate and evade?

    FWIW you’ve missed the boat on the question of ice extent – the likes of stoat & James Annan used to make this the subject of a betting pool but have since stopped as no-one will take them up on it (due to them persistently being right). Last year the lab lemming had one too. In fact last year there was quite a few goes at predicting including this one at Bob Grumbine’s site: http://moregrumbinescience.blogspot.com/2009/06/connolley-grumbine-sea-ice-bet.html I’ll follow stoat’s method and say that this year’s minimum extent will fall on or near the 1979-2006 linear regression line.

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  24. Hypothetical evidence is evidence that does not exist, how could i make a decision based on this?

    Blatant dodge. You have no answer and everybody including you knows it, but its important that we play this little game so I’ll keep asking and you’ll keep dodging.

    I’ll rephrase the question–yet again–because I’m starting to derive a bizarre sense of resigned satisfaction in watching you repeatedly dodge it.

    Direct Question (you will not answer): What would you accept as evidence, Crakar, that AGW is both real and menacing?

    Who cares what summer ice extent is in September, and how should I possibly have a basis for guessing? What does one month of extent have to do with the real issue at stake?

    Here’s an analogous question, Crakar: How many inches of rain will fall in Tasmania in September? By your logic, if you don’t answer, you’re dodging.

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  25. Interesting news from the National Snow and Ice Data Center on the extent of ice in the Arctic at the moment.

    “……Average ice extent for May 2010 was 480,000 square kilometers (185,000 square miles) greater than the record low for May, observed in 2006, and 500,000 square kilometers (193,000 square miles) below the average extent for the month. The linear rate of decline for May over the 1979 to 2010 period is now -2.41% per decade.

    The rate of decline through the month of May was the fastest in the satellite record; the previous year with the fastest daily rate of decline in May was 1980. By the end of the month, extent fell near the level recorded in 2006, the lowest in the satellite record for the end of May. Despite the rapid decline through May, average ice extent for the month was only the ninth lowest in the satellite record….”
    source: http://nsidc.org/arcticseaicenews/

    Or if you wish, you can have a look at the graphical representation here:

    What’s worse, is this is sea ice ‘extent’ – ie the area covered, and does not take into account the volume of ice (ie thickness), which has been much thinner over recent years. This may explain why it is declining so rapidly – thin ice obviously melts a lot quicker than thick ice. This is the information regarding volume:

    “…..According to PIOMAS (Pan-arctic Ice Ocean Modelling and Assimilation System), the average Arctic sea ice volume for May 2010 was 19,000 cubic kilometers (4,600 cubic miles), the lowest May volume over the 1979 to 2010 period. May 2010 volume was 42% below the 1979 maximum, and 32% below the 1979 to 2009 May average. The May 2010 ice volume is also 2.5 standard deviations below the 1979 to 2010 linear trend for May (–3,400 cubic kilometers, or -816 cubic miles, per decade)….”

    Of course, the conditions may change over the coming months, and it is difficult to make definitive predictions and statements re the longer term outcomes, but this suggests that the low in 2006/7 was not an outlyer, and will be exceeded this season. Not good!!

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  26. I read some interesting papers on Arctic sea ice today, which were either authored or co-authored by a scientist by the name of Christian Haas. Brilliant guy! Lots of experience with measuring sea ice. I believe he even gets interviewed by the newspapers.

    Of course, anyone with any intelligence always follows up what they read in the newspapers with additional research to check if what is reported is correct, and to shed light on the subject which is usually only touched on briefly in the media.

    He are a couple of things that Dr Haas has to say about ice in the Arctic:

    “….Measurements of second-year ice which still persisted at the North Pole in April 2007 indicate a reduction of late-summer second-year modal and mean ice thicknesses since 2001 of 20 and 25% to 1.65 and 1.81 m, respectively. The regime shift to younger and thinner ice could soon
    result in an ice free North Pole during summer….”

    source: http://epic.awi.de/Publications/Haa2008c.pdf (2007)

    “…..Satellite observations demonstrate a decreasing summer Arctic sea ice extent over the past ~37 years, as well as a smaller perennial sea ice zone, with a significantly accelerated decline in the last decade. Recent ice extent observations are significantly lower than predicted by any model employed by the Intergovernmental Panel on Climate Change (IPCC)….”

    source: http://adsabs.harvard.edu/abs/2009AGUFM.C41C0479L (2009)

    “….We conclude that older sea ice in much of the Arctic Ocean was of similar or even slightly larger thickness in April 2009 relative to conditions in 2007, but within the expected range of interannual variability. However, the volume of older ice may have been less overall due to a lower areal coverage, and because our surveys were still spatially limited. It seems that consequences of strong melt and ice export during and after the summer record minimum 2007 may have been compensated for by weather patterns in 2008 that were not conducive to high melt and ice dispersal in summer and may have fostered enhanced thermodynamic ice growth during a colder winter 2008/09 with less snow accumulation, as suggested by anecdotal in-situ observations in spring 2009…”

    source: http://epic.awi.de/Publications/Haa2010b.pdf (2010)

    Makes fascinating reading, and just goes to show that you should not rely on newspapers as a source for your science. If you want REAL light to be shed on a subject, I always believe it is best to go to the source. Don’t you all agree?

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  27. Duly noted . . . but I still will ride you about Germany beating Oz in World Cup, mate.

    That is, until the Krauts smoke us just as badly (or worse) in playoff play.

    (Allow me my petty barbs, Crakar. I am a small and sad man in many ways.)

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  28. Thats OK Skip i understand, the big one starts tomorrow night for us as we take on Ghana in a must win game, which will be followed by another must win game against Slovakia or Slovenia or was that Serbia? Anyway we gotta win them both.

    SBN you still there or for that matter DW? Hows those Kiwis hey bro. I till you whot thiy are e but desiptuve those All Whites.

    Seriously guys good luck with your next two games i hope you get through to the round of 16.

    Cheers for now.

    Crakar

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  29. Yeah, thanks.

    Just past 4:00 am and I’m already amped, not sleeping. I need a proper drug habit or something.

    U-S-A!

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  30. For what it’s worth Skip, thought you guys were robbed with that disallowed goal. God I need some sleep….

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  31. Thank you for the sympathy, Matt, but . . . “robbed”?

    “ROBBED”??!

    Robbery is a property crime. That game was not merely stolen; we were bent over and publicly *violated* by Coulibaly and FIFA.

    Even the Limey bastard commentator admitted it was a hose job! Oh, for the love of God . . . That SOB . . . the Chris Monckton of soccer officiating. (Apologies, Crakar; it seems like a good analogy at the moment.)

    My feeble consolation is the poms (no offense) stunk up the field and tied Algeria . . . so we’re still in this thing.

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  32. ROBBED!!!!

    We was robbed, the ball hits Kewell in the shoulder… result a red card and a gimme goal. It was the same prick that cost us the game last time (06) against the spagetti munchers.

    Speaking of which, the Kiwis had that game in the bag until the Italian player went down as if he was shot in the back of the head from a sniper in the grandstand.

    Our only hope now is the Krauts stung into action by their insipid performance against Serbia come out and belt the bejesus out of “we can only win games by getting dodgy penalties Ghana” and we beat Serbia.

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  33. Ok, Ok . . .

    I started this line and I apologize. Not your fault Crakar, but we can’t turn Coby’s blog into a sports chat forum.

    That being said I still want the last word:

    We got ROBBED!

    Ok back to CO2 residence time . . .

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  34. At post #83, I commented and provided some links on the extent of sea ice in the Artic, and remarked at the time that sea ice was declining at the fastest rate ever observed, but that the extent of sea ice was still only the ninth lowest observed for the month of May. A copy of the quote as follows:

    “….The rate of decline through the month of May was the fastest in the satellite record; the previous year with the fastest daily rate of decline in May was 1980. By the end of the month, extent fell near the level recorded in 2006, the lowest in the satellite record for the end of May. Despite the rapid decline through May, average ice extent for the month was only the ninth lowest in the satellite record….”

    I also remarked that even though the extent (area) of the ice was not the lowest observed, the volume WAS the lowest observed, with most ice being very thin. Consequently it would be subject to melt very easily. The quote I used was as follows:

    “….According to PIOMAS (Pan-arctic Ice Ocean Modelling and Assimilation System), the average Arctic sea ice volume for May 2010 was 19,000 cubic kilometers (4,600 cubic miles), the lowest May volume over the 1979 to 2010 period. May 2010 volume was 42% below the 1979 maximum, and 32% below the 1979 to 2009 May average. The May 2010 ice volume is also 2.5 standard deviations below the 1979 to 2010 linear trend for May (–3,400 cubic kilometers, or -816 cubic miles, per decade)….”

    Whilst I was cautious in my predictions about what might occur in the coming months, I finished on a pessimistic note that things did not bode well for the future.

    Well, the future is here, and sea ice in the Arctic is now at the lowest it has ever been at this time of year – below the record levels set in 2006 and 2007. Here is a link to the daily data for the 21st of June:

    In the September Sea Ice outlook published by the ‘Study of Environmental Arctic Change, estimates were examined from 16 different sources, with every single one being below the long term average, with one estimate (an outlyer admittedly)predicting ice extent as low as 1.0 million sq km. The mean of the predictions is in the region of the 2007 record.

    I wanted to finish this post by making some sort of pithy comment, but I think this time I will just let the facts speak for themselves.

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  35. Here is a link to cryosphere comparing May 1979 to May 2010.

    http://igloo.atmos.uiuc.edu/cgi-bin/test/print.sh?fm=05&fd=01&fy=1979&sm=05&sd=01&sy=2010

    Does the information in post 97 agree with this?

    http://igloo.atmos.uiuc.edu/cgi-bin/test/print.sh?fm=05&fd=01&fy=1979&sm=05&sd=01&sy=2000

    This is from May 79 to May 2000 as far as i can tell there is no difference.

    The site is quite good to compare from one year to the next just make sure you get the months the same though.

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  36. Crakar,

    1. May 1st “May”. Try comparing June 22s. http://igloo.atmos.uiuc.edu/cgi-bin/test/print.sh?fm=06&fd=22&fy=1979&sm=06&sd=22&sy=2010

    2. The lo-res comparison maps at CT seem to show a lot more ice in recent years than the hi-res main map for the same day. Compare the right hand image in the previous link to the hi-res version of the main front-page map for the same day. (Link in next post to avoid moderation.) Interesting differences. There’s more ice area on the lo-res even though it’s supposed to cut off at 30%, while the hi-res cuts off at 15%. One could then argue that maybe if we had hi-res for 1979 it would show less ice too, but the fact remains that in 1979 no one was thinking about using the NW passage, while in the last couple of years *pleasure* boats have done it.

    Like

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