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North Pole notes

I always find it interesting as to why some stories get traction in the mainstream media and why some don’t. In online science discussions, the fate of this years summer sea ice has been the focus of a significant betting pool, a test of expert prediction skills, and a week-by-week (almost) running commentary. However, none of these efforts made it on to the Today program. Instead, a rather casual article in the Independent showed the latest thickness data and that quoted Mark Serreze as saying that the area around the North Pole had 50/50 odds of being completely ice free this summer, has taken off across the media.

The headline on the piece “Exclusive: no ice at the North Pole” got the implied tense wrong, and I’m not sure that you can talk about a forecast as evidence (second heading), but still, the basis of the story is sound (Update: the headline was subsequently changed to the more accurate “Scientists warn that there may be no ice at North Pole this summer”). The key issue is that since last year’s dramatic summer ice anomaly, the winter ice that formed in that newly opened water is relatively thin (around 1 meter), compared to multi-year ice (3 meters or so). This new ice formed quite close to the Pole, and with the prevailing winds and currents (which push ice from Siberia towards Greenland) is now over the Pole itself. Given that only 30% of first year ice survives the summer, the chances that there will be significant open water at the pole itself is high.

The actuality will depend on the winds and the vagaries of Arctic weather – but it certainly bears watching. Ironically, you will be able to see what happens only if it doesn’t happen (from these web cams near the North Pole station).

This is very different from the notoriously over-excited story in the New York Times back in August 2000. In that case, the report was of the presence of some open water at the pole – which as the correction stated, is not that uncommon as ice floes and leads interact. What is being discussed here is large expanses of almost completely ice-free water. That would indeed be unprecedented since we’ve been tracking it.

So why do stories about an geographically special, but climatically unimportant, single point traditionally associated with a christianized pagan gift-giving festival garner more attention than long term statistics concerning ill-defined regions of the planet where very few people live?

I don’t really need to answer that, do I?

827 Responses to “North Pole notes”

  1. 451
    Steven Goddard says:


    Thanks much for your response.

    Interesting that Steve Connor explained the exact problem with The Independent story on this thread in post #121, yet Doug Bostrom went ahead and accused me of “lying” about it below Steve’s fully adequate explanation. Thanks for pointing that out, and I will try to get a note put into The Register article that the Independent story has been corrected.

    Re 437: “That was then, this is now”

    Hansen-Nazarenko may no longer be the best source in your estimation, but you are not disagreeing that my interpretation of the article is valid. Zender was from 2007.

    [Response: Perhaps I wasn’t clear. The figure I pointed you to was the latest IPCC assessment of forcing, which very clearly includes an assessment of the black carbon/albedo effect. Therefore quoting H&N04 as saying that isn’t included in IPCC is no longer valid (though it was at the time). You seem very fond of the Zender paper – but that too isn’t a multi-factorial attribution study and so has exactly the same problem that I highlighted above. Try Hansen et al 2005 instead (data available here). – gavin]

    Thanks for pointing me to Hansen 2001. I am familiar with the USHCN adjustments from the ORNL web site and wrote in my series “NASA’s published data is largely based on data from the US Historical Climatology Network (USHCN)” Your description of TOBS was a bit terse, and it is less than half of the upwards USHCN adjustment. As you know, some people have raised serious questions about the accuracy of the FILNET, URBAN and SHAP adjustments.

    [Response: GISTEMP doesn’t use the FILNET or URBAN adjustments. SHAP is something else – but are you arguing that adjustments for station moves shouldn’t be accounted for? In any case, that is done by NOAA, not NASA. – gavin]

    Gavin, I’m curious to hear your interpretation of this graph?

    [Response: What about it? – gavin]

  2. 452
    Rod B says:

    Ray (443), is “What gets us into trouble is not what we don’t know. It’s what we know for sure that just ain’t so” referring to Aaron or to you?? ;-)

  3. 453
    dhogaza says:

    His sailors may have been afraid of falling off the edge; but no scientist of the time was. Educated people have known the world was round since Eratosthenes measured its size circa 300 BC.

    Or perhaps his sailors were simply afraid of the scurvy, which was plaguing them as it did every lengthy sea voyage of the era. Mortality rates from scurvy were high enough to cause anyone to fear a long voyage.

    And perhaps they were afraid of unknown seas with uncharted reefs, unknown weather patterns, of storms blowing their ships onto unknown shores …

    Face it, a long voyage of exploration into the unknown at that time was not quite suicidal but … it wasn’t that far from it. Look up how many of Magellan’s sailors survived the circumnavigation (and keep in mind that Magellan was not one of them).

    Columbus wasn’t arguing that the world was flat, he was arguing that the distance to the east was much smaller than it really was, with or without a friggin’ unknown New World forcing one to sail around Cape Horn to get there.

    It was Columbus that was wrong, not the learned of the day who were aware of Eratosthenes work. Not, that is, the intellectual establishment (science as we know it today did not yet exist).

    I spend time on conservative forums reading from one side of the equation, and I feel like it’s appropriate for me to spend the time to get educated properly on what is going on from the other side of the aisle.

    So, if you want to talk about taking one’s credibility about science to absolute zero, think about what I’m saying.

    Well, you’ve just taken your credibility about science to zero, Paul, because you’ve just described climate science as being “liberal”, which is the same as saying climate science is not science at all, but simply advocacy.

    And you wonder why people don’t take you seriously …

  4. 454
    Aaron says:

    #443 (Ray)

    Ray, I am not “blindly parroting” anything. If you honestly don’t think that climate science is still young and has had many big developments in recent years (I see you didn’t even acknowledge my points about the natural ocean cycles just beginning to be understood), then you are the blind one. The difficult thing about climate science is that it deals with such long time periods, and the changes that occur over those periods are not easy to observe, as well as the forces that drive them. If you think that climatologists have it all figured out right now, you are sorely mistaken. There is so much that is still not known about climate change and climate forcings…which is why every year we hear about so many new theories and possible tweaks that should be made to the climate models. It is a very exciting time to be a climate scientist, I think, because there are still so many discoveries to be made.

    I am not a skeptic of climate science at all, I think it has grown a lot in the last 30 years especially. However, I still see room for debate on the AGW issue because of the incredible complexities of climate itself. Based on what we know, increases in CO2 SHOULD cause atmospheric warming…how much, and what feedbacks interact and alter the impacts, we just don’t know at this point. At least, that’s the conclusion I have reached for myself…at this point.

    As far as your statements about the “denialists” – I think you are being a little extreme. There are some no doubt who publish junk that has no scientific merit, but not all are like that. I think sometimes they look too hard for problems in AGW theory (every theory is going to have some things it cannot explain), but I also think there are some people who honestly don’t believe the evidence favors catastrophic global warming. You make them all out to be crackpots (just as many of them make all AGWers to be religious zealots), but I have encountered a fair number of reasonable-minded skeptics who are not like that at all. If you want me to go into more detail about why I find their arguments somewhat reasonable I will, but I am not here to defend them, or to attack your beliefs.

  5. 455
    Mark says:

    Paul: “Even Evolution is a “theory” not proven scientific fact”

    So why are we worried about Bird Flu. I ain’t no bird, foo!

  6. 456
    Mark says:

    Re: #440

    [ Just as the earth has tides from the sun and the moon, the sun will have tides from the Milky Way and its planets.

    “The Milky Way and its planets” implies that you were confusing the galaxy with the Solar system, a la Alfred Bester. As I showed, tides from the Milky Way galaxy are irrelevant.]

    Yup, still doesn’t say those tidal effects are important.

    Just that they exist.

    Ergo “Huh? The sun is part of the milky way” has nothing (absolutely nothing) to do with refuting the sun is affected by tidal forces from the milky way. That it makes 10^-10m difference IS.

    However, you got to that point rather late.

    If you don’t like being corrected, don’t make mistakes.

  7. 457
    Doug Bostrom says:

    #432 “Steven Goddard”:

    First, it is scurrilous to reprint a private E-mail on a public forum without the author’s consent or knowledge. Then to call the other person a “liar” behind their back is quite remarkable behaviour. I have attempted to deal with you in a civil fashion, and you have violated all decorum.

    [blah-blah, woof-woof redacted]

    Also, you are misrepresenting Hansen’s paper.

    I tried to cover this at The Register, comments need to meet a mysterious threshold for acceptability (invective usually ok, lengthy detailed rebuttals less so) so -I- alerted -you- that I’d posted a response here. Thanks at least for bringing your pseudonym to a place where you can be exposed to some real expertise (not me, I’m not an expert but it’s still easy for me to sail through your gaping holes…)

    Meanwhile, private email? From “anonymous”? No such thing. You volunteered for the “Anonymous Army” and you can resign any time you like, either by stepping into the light with your CV,


    I’m misrepresenting Hansen’s paper?

    You should put down your knitting needles, because your yarn is getting all tangled:

    Your “In 2004, Dr Hansen returned to the subject. This time, he explained (pdf) that most of Arctic warming and melting is due to dirty snow from soot, not CO2.”

    morphs into:

    “By any reasonable interpretation Hansen did imply that most of the warming in the Arctic is due to soot.”

    Explain=Imply? Even if your “interpretation” were correct, that’s quite a loss of definition, eh? Doesn’t matter what the UC articles says, it had nothing to do with Hansen’s explanation/implication/whole-cloth fabrication as created by Steven Goddard.

    Your problem, Steven, is that you weave such a tangled web you can’t help but trip yourself up. If you’d found just –one– good chink in Hansen’s armor and worked on that, you might have come out of this smelling a little better, maybe.


    As to the apology, ok, try on “suffering from paranoid delusions” for size. (The Independent changed their headline because of you. The “ice free Pole”, full of ice as far as the eye can see. Sea ice coverage graphs that look flat to your eyes only. The list goes on…)

    Last night I’d just about persuaded myself that I should stop badgering you because my cavalier remark about “paranoid delusions” might actually be true in which case I’m just being cruel. This morning I see that my repost of the piece I wrote here over to The Register is missing, despite your invitation to bring specific concerns there, and I see that my comprehensive correction to your lunatic hallucination of submarines waltzing about in a mill pond at the North Pole is missing.* Hard to be nice in the face of that, and your general contributions to collective cultural dementia.

    *Turns out the subs had search extensively for polynyas, crash their way upward through masses of a mineral found in abundance at the Pole and known as “ice”, stand guard w/rifles against polar bears which presumably would be walking most of the way to Lunch, etc.

    [Response: I’ve edited out some of the invective in this post and I’m tempted to edit out more. This is not a free for all, and I’m not going to allow any more of this venting. Please stick to the issues and matters of fact – that goes for everyone. – gavin]

  8. 458
    Mark says:

    Paul states:

    “If you look at the info, you’ll see that there was a great amount of debate but that the spherical concept did originate (in the Western world) in the third century BC. There were many people and many descriptions of the earth as being a flat sphere.”

    Nope, the Mayans knew the earth was round and knew the moon was too. Admittedly they thought both rotated around the earth.

    But that was a lot earlier and definitely (unless plate tectonics was a lot faster in them dais) not in the western world. New world, yes.

  9. 459
    Mark says:


    STEP 1: Deliberate acquiescence should be hidden in reasonableness.

    cf #424. “So I am still making up my mind until I see better proof from either side.”

    See, one side says “don’t change because GW isn’t A” and the other side says “change because GW is A”. So you’ll do nothing until both sides have proven their statements.

    Now to me, this looks like believing the anti-AGW crowd. At the very least, all they have to do to get their way is NOT prove anything. You shall be doing what they want.

    Alternatively, just as you don’t let your child walk the dark streets “in case they get abducted”, you should likewise do something to remove the possibility of bad things happening. If they don’t turn up, you can go back to what you were doing. You can’t so easily undo the changes you did that cause GW.

  10. 460
    Mark says:

    [> No, if Hank in posting #328 had said “huh? …

    If I’d written anything in 328, my name would be Barton.
    Check your sources.]

    Aye, sorry.

    Pity there’s not a way to say sorry that doesn’t fill this already overlong thread…

    Still, I ought to apologise, so I do.

  11. 461

    Odd piece of bad timing? Especially for the remaining old ice to continue drifting towards the North Atlantic:

    This is odd…. Quite peculiar.

  12. 462
    Dan says:

    re: 446. Paul, as has been pointed out several times already, it has become clear that you simply do not have a full understanding of the scientific method/process with regards to theories. When a new theory comes out it is tested and peer-reviewed. When you have a testable, peer-reviewed theory re: global warming that relies on natural forces/variation and not anthropogenic CO2 and GHGs to discuss, we will be waiting. Meanwhile, the scientific method has worked for centuries. As it has for AGW.

    BTW, you continue to refer to “proof” or “proven”. Please see post 449.

  13. 463
    Alan Millar says:

    “Gavin, I’m curious to hear your interpretation of this graph?

    [Response: What about it? – gavin]”

    I think Steve is pointing out that it is currently cooler than in 1988, the year, coincidently, Mr Hanson made his seminal statement to Congress.

    Steve probably would like to see a comment on how this can be, given that A/CO2 emmisions have increased at a greater rate than predicted at that time. What natural causes can have stopped the huge forcings that the theory states has been happening since this time?

    [Response: Weather. Long term trends 1988-2008 are all positive – which is, as I keep saying, the key to climate change. – gavin]

  14. 464
    Phil. Felton says:

    Re #407
    For the longest time, the world’s leading scientists and scholars told us the world was flat. That the world was the center of the universe.

    Not for over 2000 yrs in the first case, accurate estimates of the radius of the earth have been available for about as long. In the latter this was a dogma of the church and heresy was severely punished because of this western scientists were rather late in adopting heliocentricity (unlike the arabs and indians).

    A lot of the problem with the concept of “flat earth” being scientifically acceptable is from the romantic notion that Columbus’ crew was reluctant to sail to the New World because of falling off the edge of the world. It may be that there was little to no scientific belief in it, but there certainly points to there being a debate, and one with serious social consequences.

    Which is a nonsensical notion in the first place, sailors had long known that the world was round.
    There was a debate but it’s not the one you mention: it was between Columbus who used an old and discredited value of the radius of the earth which gave a distance to Japan of about 3,000 miles, whereas the Queen’s advisors were using a much more accurate value which gave a distance to Japan of over 9,000 miles (well beyond the range of their ships). The sailors were scared of sailing so far that they would not be able to make it back. Columbus’s voyage ultimately proved the advisors right although to his deathbed C believed that he had reached Asia.

  15. 465
    Dan says:

    re: 447. Rod, I’d be quite interested if you could find a scientific study/paper re: AGW which refers to it as scientifically “proven”. This is not simply semantics. When you say “proof par excellence”, that is not within the scientific realm. As you pointed out, “proof” does have a clear and accepted meaning outside of mathematics. But I am specifically talking about the meaning within science.

  16. 466
    Doug Bostrom says:

    #451 “Steven Goddard”:

    Interesting that Steve Connor explained the exact problem with The Independent story on this thread in post #121, yet Doug Bostrom went ahead and accused me of “lying” about it below Steve’s fully adequate explanation. Thanks for pointing that out, and I will try to get a note put into The Register article that the Independent story has been corrected.

    I grant you that online newspaper headlines are frangible, so I’ll take that –single– item off my list of gripes. But as usual with you, there’s more to the story. Here’s what you wrote:

    “The North Pole will be ice-free this summer “for the first time in human history,” wrote Steve Connor in The Independent. Or so the experts at the National Snow and Ice Data Center (NSIDC) in Boulder, Colorado predict. ”

    Here’s everything that was said by NSIDC in the article:

    “From the viewpoint of science, the North Pole is just another point on the globe, but symbolically it is hugely important. There is supposed to be ice at the North Pole, not open water,” said Mark Serreze of the US National Snow and Ice Data Centre in Colorado.


    “The issue is that, for the first time that I am aware of, the North Pole is covered with extensive first-year ice – ice that formed last autumn and winter. I’d say it’s even-odds whether the North Pole melts out,” said Dr Serreze.

    and finally:

    “Indeed, for the Arctic as a whole, the melt season started with even more thin ice than in 2007, hence concerns that we may even beat last year’s sea-ice minimum. We’ll see what happens, a great deal depends on the weather patterns in July and August,” he said.

    Now I realize this is a matter of “interpretation” as you call it, but where in that did “experts at the National Snow and Ice Data Center (NSIDC) in Boulder, Colorado predict” the Pole would be ice-free? The closest statement to that is Dr. Serreze’s “it’s even-odds whether the North Pole melts out”, a very long way from your “interpretation”.

    This is exactly what I mean when I say you don’t know when to stop.

  17. 467
    Steven Goddard says:

    Re Gavin 451 :

    Thanks again for your courteous response

    It appears that UAH and RSS data would indicate that global temperatures over the last 20 years may have fallen below even the most conservative IPCC scenarios. Satellite data for May had the tropics at it’s lowest value of any May on record. UAH June had nearly all areas below the 30 year mean, despite a neutral ENSO.

    Answering your earlier remark – I have never accused anyone of “fixing data” or intentionally skewing records. All human beings tend to preferentially look for information which agrees with their core value system. When there is a lot of subjective data post-processing and adjustment occurring, this becomes increasingly problematic. Some people believe that UHI is not properly accounted for in GISS data. This is a highly subjective judgment call. Some people believe that many GHCN and USHCN stations are of inadequate quality. Once, again another judgment call.

    No one is infallible and it is completely appropriate to look for data patterns and changes in data which may indicate an inherent bias or error. That is an essential part of the scientific and journalistic process.

    [Response: As above, estimates of change associated with a single month are completely irrelevant to climate. For instance, take the exact day June 23 and specific location – it was warmer in DC in 1988 than in 2008. Does that mean that the planet has cooled over that period? Obviously not. What about a week, and the whole north eat coast? No? well try the month and the continental US? No again. The global mean trends are derived from global mean trends – nothing else will do! PS. I do hope we can see more of this reasonable tone in your future pieces. – gavin]

  18. 468
    Aaron says:


    Mark, I’m not sure if you are accusing me of lying, I hope you are not. I am being as honest as I possibly can – I am admitting that I do not see conclusive proof from either side of this debate to convince me. When looking at evidence, I try to be as logical as possible, and the “worst-case scenarios” presented by some AGWers appeal to my feelings, not to my sense of logic.

    I have looked at as much evidence as I can, from both sides, and I find that both sides tend to fixate too much on short term examples (latest ten/twenty year trend, sea ice, etc), and I need more compelling evidence. To me, the most compelling evidence for AGW is not temperature trends, but the physics, the mechanisms behind CO2 warming. They seem to indicate that some warming MUST occur. On the other hand, the most compelling argument from the skeptics is previous natural cycles and the PDO/NPI variations that appear to have better correlation with temperatures than CO2.

    To give you another example of something I am undecided on: solar forcing. Many skeptics will argue that solar activity is a big climate influence, even though TSI measurements, etc. would indicate it is not. Nevertheless, there do seem to be some temperature correlations with past solar activity. So I do not see compelling evidence on either side to convince me that solar forcing on climate is signficant.

  19. 469
    Doug Bostrom says:


    Gavin, thanks for the edits. Nearly everybody can benefit from red ink and there’s no doubt I’m overheated about the matter at hand. Meanwhile the author is here now which is a good thing for all.

  20. 470
    John L. McCormick says:

    RE # 468; Aaron, if you say you are looking for PROOF one more time, I might say you are lying.

    Can you please accept what so many honest contributors have said in this long and lost thread; SCIENCE DOES NOT WORK TOWARDS PROOF; MATH DOES. Please; enough with the proof searching….unless you are working to triangulate.

    John McCormick

  21. 471
    CobblyWorlds says:

    Steven Goddard.

    1) What was your purpose in citing tiny areas of open water in the Arctic way back in 2000?

    2) Why did you think a graph of ice area for both poles summed was more appropriate than the Arctic area?

    a)What was your rationale for selecting a 1980s paper by Hansen?
    b)Were you unaware that current models don’t show equal warming at both poles?

    4) Why did you not feel it appropriate to mention in your article that published papers suggest a role for enhanced greenhouse effect driven stratospheric cooling?

    5) Were you aware that Amundsen’s 1903-06 transit through the NW Passage was done in much worse conditions than we saw in the NW passage last year?

    6) Why did you not consider it appropriate to mention the caveats that Serreze/Meir/Stroeve made concerning weather and latitude (i.e. insolation angle)?

    #486 Aaron

    Correlation does not imply causation.

    The correlation between CO2 and paleoclimatic temperatures would mean nothing were it not for the sound physical basis for knowing CO2 will cause warming as it’s atmospheric concentration is raised. It’s that understanding that makes the correlation significant. Without mechanism the correlation is intriguing, but no more.

  22. 472
    Aaron says:


    John, why does looking for proof indicate dishonesty? What would you say science working towards? I think that the goal of science is to work towards greater knowledge and understanding of the physical world. Once a certain amount of knowledge is attained on something, scientific rules and laws can be created and applied. That, to me, is the process of reaching scientific proof. Arguing the exact meaning of proof is merely semantics: I’m just saying a certain amount of evidence is needed to claim something as a scientific certainty.

    If I am trying to make a decision on something, I am going to carefully weigh the arguments from both sides and make my own decision. This attitude of: “You are not completely sold on AGW, you must not comprehend science, or else you would see the truth as I do”, is rather off-putting. I happen to see this as a very complex issue that will take more time to resolve for certain.

    [Response: Your asking for ‘scientific certainty’ is a chimera. It doesn’t exist – not for medical procedures, not for epidemiology, not for climate science. Yet people (quite sensibly) try to lose weight if they are obese, get vaccinated, and (hopefully) try to reduce their carbon emissions. Thus demanding certainty is equivalent to demonstrating that you will never be persuaded, and thus signalling to those who might be minded to help you that there is no point. This is not a new tactic, nor is it merely a semantic point. There really is a big difference between beyond reasonable doubt and absolute certainty. In your real life, you do not depend on absolute certainty for anything practical – why should climate change be an exception? – gavin]

  23. 473
    SecularAnimist says:

    Paul wrote: “To those of us who aren’t ‘believers’, there is a lot of debate. And there are a lot of legitimate questions that frankly, those of us who look at it from the outside have. For the debate to be ‘over’, it has to be accepted science.”

    With all due respect, you are merely parading your ignorance as though it were some kind of challenge to the science.

    Anthropogenic global warming and climate change is “accepted science” — indeed it is overwhelmingly accepted science. There is absolutely no genuine scientific debate about the reality of anthropogenic global warming, period. You “argument” amounts to declaring that because you are ignorant of the science — as your comments have repeatedly demonstrated — the science must not be “accepted”.

    There certainly are “legitimate” questions that may be, and should be, asked by those such as yourself who are just beginning to learn about the issue. But those questions arise from your lack of knowledge, not from any problem with the science of global warming. If you keep asking legitimate questions, and learning from the answers, your understanding will grow. But to assert that because you don’t understand the science and don’t know the facts, there is something wrong with the science, or global warming is a “religion” or a “liberal conspiracy”, is absurd.

  24. 474
    Paul Melanson says:

    This post has certainly been a “lightening rod” for denialist “discussions” (I use this term loosely because a lot of it is “sniping” than an effort to start a discussion), no doubt due to the visual and emotional impact an ice-free North Pole would have.

    Re: Columbus and the flat earth. Columbus was arguing for a smaller earth, not a spherical one (by the way, what the heck is a “flat sphere?”). By shrinking the size of the earth and expanding the breath of Eurasia he could argue that it was practical to sail west to get to the Far East. Not a very good example for good vs. bad science, but maybe one for “dumb luck.” Denialists may take heart, but I’m at a loss as to what “new world” might intervene in the path of our carbon usage and save our biscuits like America saved Columbus’.

    A better example than a belief in a “flat earth” might be something that happened to me in the late 70’s at a party. Someone I had just met, after finding out I was a chemist, pressed me for “the chemical you can add to water to make it burn like gasoline.” His reasoning was like this: 1) Gasoline and water are both liquids, 2) The biggest difference I can see is that gasoline has a distinctive odor that water doesn’t, 3) You can add things to water to make it smell (e.g. perfume), so thus, 4) You should be able to add something to water to make it like gasoline which would mean you could use it in your car a fuel. I tried to argue with him using any number of simple examples, but nothing broke through. If it hinted of chemistry, like oxidation and reduction, I was confusing him with technical terms, if I tried to divorce it from unfamiliar concepts I was “talking down” to him. It was not only a complete waste of my time, the person left thinking I was part of an OPEC conspiracy. You can lead a horse to water…

    P.S. Although I’m both “Paul” and “Paul M.” I’m not the one posting here under either of those names. Some here thought that I was posting denialist arguments when I was simply trying to quote them (#217), but I was unable to put them all in italics for quoting (I’m not very posting-format savvy).

  25. 475
    David B. Benson says:

    Paul (430) — Then you first ought to learn some actual climatology. One way is the use the Start Here link at the top of the page. Another is to read “The Discovery of Global Warming” by Spencer Weart:

    Review of above:

    A third is to read a beginning text on the subject. I suggest starting with W.F. Ruddiman’s “Earth Climate: Past and Future”.

  26. 476
    Rod B says:

    Dan (465), it’s probably a matter of definition, but IMO when someone “validates” AGW with umpteen pieces of evidence that rattle on for sentence after sentence, and uses every probative word in the book except “proof”, …they’re proving it. No matter how they rationalize their treatise. Otherwise, they would lightly acknowledge us sceptics (even while asserting we are incorrect, even tiresome) instead of telling us we’re just way too stupid and blind (and probably hang with bad people) if we can’t see the mounds of (non) proof lying around.

  27. 477
    Tom Dayton says:

    A nit: To prevent unnecessary arguments, I suggest folks not use the most common turn of phrase “Correlation does not imply causation.” The correct phrase is “Correlation is insufficient evidence of causation.” I realize that most folks know what is meant. But we’ve had arguments break out over similarly loose language.

    (Correlation is the heart of causation. Anyone wanting to dive into the topic–but you should wear deep-sea gear–should read The Cement of the Universe: A Study of Causation, by J.L. Mackie.)

  28. 478
    Rod B says:

    ps see SecularAnimist’s 473 as a rough example of what I’m saying.

    Gavin, your point as stated is well taken, but we are not talking about “proof certain (100%)” which is only mathematical. We’re talking of proof “par excellence” (my term) that is probably a scientific proof exceeding legal’s beyond a reasonable doubt, but less than absolutely certainty. But “scientific” proof it is. I do not understand the aversion to the term (other than a bit because it might be misinterpreted) when it’s clearly what is being attempted.

  29. 479
    David B. Benson says:

    From the Free Online Dictionary, we have

    proof n.
    1. The evidence or argument that com-pels the mind to accept an assertion as true.
    a. The validation of a proposition by application of specified rules, as of induction or deduction, to assumptions, axioms, and sequentially derived conclusions.
    b. A statement or argument used in such a validation.
    a. Convincing or persuasive demonstration: was asked for proof of his identity; an employment history that was proof of her dependability.
    b. The state of being convinced or persuaded by consideration of evidence.
    4. Determination of the quality of something by testing; trial: put one’s beliefs to the proof.
    5. Law The result or effect of evidence; the establishment or denial of a fact by evidence.

    None of these variants are actually very helpful to practioners of the

    except possibly as the scientific method applies to mathematics; in mathematics deductive logic alone is used to structure the proofs of theorems.

    For experimental science, it is far better to use the Bayesian terminology of ‘confirm’ and ‘disconfirm’ when relating data to hypotheses. This is sometimes done quite formally, but often enough scientists are but informal Bayesians; this works quite well.

  30. 480
    CobblyWorlds says:

    #477 Tom Dayton, noted. Thanks.

  31. 481
    Hank Roberts says:

    > solar activity [not is, but was] a big climate
    > influence, even though TSI measurements, etc. would
    > indicate it [not is, but was] not [since the middle of the 1900s].

    Get the details right in the description, there’s no disagreement about the facts.

  32. 482
    Aaron says:


    I appreciate your response, but you too seem to misunderstand me. I am not beyond being persuaded at all by evidence. In fact, I see strong scientific evidence of many things (gravity, a round earth, viral infections, evolution/natural selection, recurring weather patterns, energy conservation, etc), and I have high certainty in the scientific validity of those things. However, I think it is too soon to reach that conclusion with AGW (especially catastrophic AGW), as more empirical evidence is needed. That’s just my personal opinion, though, I understand that others feel there is plenty of evidence to support their viewpoint.

    Alternately, I would believe wholeheartedly in AGW if I saw no other reasonable explanations for the warming that has been seen in the past 100 years or so. However, I think there are some plausible natural explanations for the climate change that has occurred, and so even though the physics of CO2 concentration in the atmosphere would indicate a likely rise in temperature, I cannot rule out that natural forces have also had quite a bit of influence on our climate.

    Therefore, my position as of right now is that natural forcings and human forcings have *both probably* contributed to the observed climate change. I am inclined to think CO2 is more responsible than natural forcings since at least 1950…but what I really hope for is substantial negative forcings from the ocean cycles and solar the next 10 years or so. This should help clear things up quite a bit…if GHG’s are indeed the primary climate force, then global temps should continue to rise (with some variability, of course) regardless of low solar cycles or historically cooler oceanic phases.

  33. 483
    Hank Roberts says:

    Aaron, read up on ocean pH.

  34. 484
    Tim McDermott says:

    Paul Melanson: italics use an i-tag followed by the text to be in italics, followed by an /i-tag. “Tag” means preceded by the less-than sign and followed by the greater-than sign.

    You will find more than you ever wanted to know about HTML by googling “html tags”

  35. 485
    l david cooke says:

    RE: 451

    Hey Steven Goddard and Dr. Schmidt,

    I know the discussion has moved beyond this region of the thread, (RE posting 451). However, I suspect the data contained within the link below may be of high value to not only the referenced exchange; but, to the thread as a whole. To this end let me share my question of whether either of you reviewed the more recent data appearing to come from the ARCTAS Mission?

    I understand Dr. Schmidt’s pointing to the IPCC AR4, as it is likely the most reviewed document to date; hence, more likely to reflect the greatest accuracy. personally, I just thought it would be of value to review the data there in reference to more recent data collections.

    It appears that some of the questions that Steven Goddard is attempting to address are better explained within the NOAA paper. (I have yet, to complete the papers.) I have found a lot of interesting hypothesis being examined within and it appears to be relevant to your discussion. Hopefully, this interruption in the threads progression will help advance the discussions here.

    RE: 482

    Hey Aaron,

    I have been reviewing the various posts from Mark, Paul and yourself and find that many of the points brought up have been addressed in the past, if not here, at least in other similar forums. Personally, I remain a skeptic in regards to AGW; however, the state of the data at this point seems to support the validity of the theory. (Keep in mind, it is difficult to prove a theory, if you want to challenge a theory you need to have the data to disprove it. (A basic premise I have stolen from John Mason at UKweatherworld.))

    As the science advances the basic underlying processes that are occurring appear to be following the AGW trending that has been laid out for over 24 years. As Dr. Schmidt has already shared there is natural and even Anthropogenic variability involved in the recent synoptic variations, suggesting that there may be a short term deviation from the noted cause and effect model scenarios.

    As to your hopes, I will share a small thought that has occurred to me in regards to concerns regarding the CO2 uptake in the oceans. The evidence to date points to a reduction or a flattening of uptake in the Southern Pacific and North Atlantic.

    It has been noted in a recent study that the PH of the ocean water has dropped to @ 7.4 and the uptake of CO2 has plateaued. (However, the acid that appears to be contributing to the change in PH has not been documented, to my knowledge. This brings up the question of possible biologic decay and the acidic bacterial wastes generated as the bacteria break down dead phytoplankton in the oceans.) There may be hope; however, at this time it appears to be related to a process that is in decline.

    Dave Cooke

  36. 486
    llewelly says:

    Aaron, #482:

    … but what I really hope for is substantial negative forcings from the ocean cycles and solar the next 10 years or so.

    By far the most likely negative climate forcing is the staggering increase in aerosols from Asia. (And perhaps this will help explain the global temperature trends of the last 10 years or so. But not all aerosols cause cooling. ) After that is the potential of a large volcanic eruption. But Asia will likely be forces to reduce its aerosol pollution – and in any case, CO2 has a far longer atmospheric lifetime than any aerosol. So there’s essentially no prospect of a negative forcing that will outweigh CO2 over the next 50 years or more.

  37. 487
    Timothy Chase says:

    Aaron wrote in 482:

    Therefore, my position as of right now is that natural forcings and human forcings have *both probably* contributed to the observed climate change. I am inclined to think CO2 is more responsible than natural forcings since at least 1950…but what I really hope for is substantial negative forcings from the ocean cycles and solar the next 10 years or so. This should help clear things up quite a bit…if GHG’s are indeed the primary climate force, then global temps should continue to rise (with some variability, of course) regardless of low solar cycles or historically cooler oceanic phases.

    Why ten years, Aaron?

    We have seen the warming of the past century. Those negative feedbacks could have kicked in during any one of those decades.

    Why not twenty years from now?

    Why not thirty? Forty? Or a hundred years from now?

    Thing of it is, you can always claim that the feedbacks that are going to bring us back from the brink are only a few years off — no matter how bad things get. But in the meantime we will be committing ourselves to business as usual with new energy infrastructure — in all likelihood alternate fossil fuels. Oil from coal with twice the emissions per unit of energy. Oil from tar sands with three times the emissions per unit of energy. New coal mines in China and other parts of the world.

    Why didn’t those negative feedbacks kick in half a million years ago — or any of the years in between? We have a paleoclimate record that shows that temperature and atmospheric carbon dioxide are strongly correlated. Approximately 2.8 C per doubling. We get the same sensitivity to the forcing from carbon dioxide as we do from solar radiation and roughly the same from the aerosols due to volcanoes.

    There is of course some uncertainty in any of the methods used to estimate climate sensitivity, but it is greater on the high side than the low — more likely to be a half a degree higher than half a degree below the central estimate. However, this climate sensitivity which they estimate takes into account only fast feedbacks. It doesn’t as of yet take into account the feedbacks due to the carbon cycle and it doesn’t take into account the feedbacks due to ice sheets. Feedbacks due to the latter are positive. Ice, afterall, melts.

    And there is a great deal of evidence that feedbacks through the carbon cycle will be strong and predominantly positive. As droughts increase in frequency, duration and severity flora become a carbon source. As temperatures rise, the ocean has a reduced capacity to absorb or even hold carbon dioxide. As temperatures rise, permafrost melts — and the deeper it goes the closer it gets to methane-rich yedoma. As temperatures rise along the shallow coasts, the likelihood of massive releases from methane cathrates rise as well.

    Its happened on several occasions in the Earth’s past. It has happened on a scale scarcely imaginable. The release of carbon dioxide on a scale sufficient to cause runaway global warming. One of those times was 251 million years ago. A Siberian supervolcano resulted in what is sometimes called the “Permian-Triassic Extinction” or more simply, “The Great Dying.” By the time it was done, the majority of the carbon in the biosphere had been converted to atmospheric carbon dioxide.

    It is unlikely that we will be able to cause something on quite that scale — but there is good reason to believe that a great many lives hang balance over what we do in the next decade or so — particularly with the inertia which will exist within the system.

  38. 488
    Phil Scadden says:

    Aaron says. “I think there are some plausible natural explanations for the climate change”.

    And this is where we disagree. Just where are the published papers that account for observed temperature record which are somehow negating the changes in CO2 concentration in the atmosphere? What I see is a lot of hand waving, without any serious attempt to create an alternative model. Why do you suppose carbon-lobby funds advocacy instead of trying to build their own non-AGW model?

    You cant have certainty in science because you cant know for sure that some new insight and flight of the human imagination wont find a better model tomorrow. However, you can do some risk-analysis and decide whether you want to find out what the upper end of the future prediction might look likes. When the prevailing model says we would be in hell, then I’ll back solutions that go there rather than hoping somehow that the model is wrong.

  39. 489
    Steven Goddard says:

    Re 471

    Dr. Hansen’s 20th anniversary comment “We see a tipping point occurring right before our eyes… The Arctic is the first tipping point and it’s occurring exactly the way we said it would”

    appears to have been intended to indicate that he believes that his 1980s CO2 predictions have borne out. That is certainly how it was interpreted by the press and politicians.

    Yet, his writings from the 1980s indicated that we should see symmetrical warming in the Antarctic, which has not happened. figure 2-2.
    Some NASA maps show significant cooling across most of the Antarctic.

    [Response: It’s not symmetric because the ocean dynamics are different in the South. Slower warming in Antarctic has been expected for over a decade. I’m sure that you’ll be equally critical of people who said in the 1980’s that global warming wouldn’t continue at all. – gavin]

    Dr. Hansen also predicted maximum mid-troposphere (200mb) equatorial warming which has not happened – same figure 2-2

    [Response: You are completely off-base with this one. The TMT is not a ‘mid-troposphere’ signal – instead it integrates over the mid-troposphere and lower stratosphere – one of which has been warming and one cooling, thus the integral is pretty flat. This has been known for decades. Instead, look at the multiple recent papers on the radiosonde data – the mid-troposphere is likely warming as the models suggest they should. – gavin]

    Additionally we now know that a substantial portion of the Arctic warming which has been observed is due to soot and ozone. Anyone who flies over western Greenland in late summer or fall can plainly see the black snow along the margins of the ice sheet and around the moulins.

    [Response: You are mostly seeing water not soot. Black carbon does play a role, but perhaps you’d like to demonstrate your attribution study that takes all of the changes and works out exactly what caused what? If you can’t, then your statement is no more defensible than someone saying it’s all the sun. – gavin]

    The models do not explain well the extensive Arctic cooling which occurred from 1940-1970, and they do not explain why (according to GISS records) most Arctic temperatures were at least as high in the 1940s as they are now – despite substantially lower CO2 levels.

    [Response: Not true. – gavin]

    Given all of these shortfalls, I don’t see how the case can be made that we have an adequate understanding of what is going on at the poles. We certainly did not 20 years ago.

    [Response: Yet out of all this uncertainty, you claim complete certainty that it is all due to soot? Huh. – gavin]

    The case for the Arctic being at a “tipping point” is also quite subjective. The Greenland ice sheet is having an exceptionally cold summer, and Arctic sea ice is not headed for a repeat of last summer.

    Temperatures remain cold at the pole.

    [Response: Temperatures are cold at the poles. Truly profound. – gavin]

  40. 490
    Mark says:

    [Therefore, my position as of right now is that natural forcings and human forcings have *both probably* contributed to the observed climate change.]

    What other forcings are there? Supernatural?

    And if humans are contributing to the observed climate change, how about NOT contributing until we do know exactly what we’re doing?

    It’s not like we can move to another apartment when we’ve got this one in such a mess…

  41. 491
    Mark says:

    Hank in #481, sounds like my complaint with “Huh? The sun is part of the milky way”…

  42. 492

    Paul writes:

    What if, tomorrow, geologists announced that they had determined that the core of the earth was expanding for some unknown reason, and the expansion was what was causing a heating of the earth, and they had calculated models that proved it?

    I’d say they were on drugs. We’ve measured the heat from the Earth and it isn’t enough to cause the observed warming by orders of magnitude. The average geothermal flux is 0.087 watts per square meter. Compare to 237 W m-2 from absorbed sunlight.

  43. 493

    rod writes:

    the history BPL cites is of one or two outliers who had an idea even before Boltzmann was being thrown out for his “stupid” theory of gases, but were not given the time of day and got virtually zero acceptance in scientific circles.

    That is not true. Debate about what had caused the ice ages was a big scientific issue in the late 19th century and continued to be until about 1970. And the existence of the greenhouse effect has been accepted since the early 19th century. The fact is there was a science of climatology in the 19th century, it is older than quantum mechanics, and to say climate science is a young field is just plain wrong.

  44. 494

    Aaron writes:

    If you honestly don’t think that climate science is still young and has had many big developments in recent years (I see you didn’t even acknowledge my points about the natural ocean cycles just beginning to be understood), then you are the blind one.

    No matter how many times you write that climate science is a young field, you will still be wrong. It isn’t. Deal with it.

  45. 495

    Mark posts:

    If you don’t like being corrected, don’t make mistakes.

    Confusing the Milky Way Galaxy with the Solar System is a mistake. Implying that tides from the Milky Way influenced the Sun significantly is a mistake. Pointing out those two mistakes is not a mistake.

  46. 496
    Mark says:

    Re #495

    Uh, that wasn’t the orignal huff n puff.

    #328 Barton Paul Levenson Says:
    5 July 2008 at 6:35 AM

    Alastair writes:

    the sun will have tides from the Milky Way

    Huh? The Milky Way is the galaxy we’re in.

    So? What does “The mily way is the galaxy we’re in” relate to whether the sun will have tides from the milky way? You were either dribbling or making a mistake in thinking this rebutted Alastair’s comment.

    Feel free to tell us why you brought up this irrelevancy if neither are correct.

    [Response: Drop it – this is pointless and uninteresting. – gavin]

  47. 497
    Steven Goddard says:


    The point about temperatures being cold at the pole is that we are at peak melt season in the Arctic, and as the season winds down over the next 3-4 weeks it is increasingly unlikely that the predictions of an ice-free pole will be realized. That is the topic here after all.

    [Response: It’s always cold at the pole – even when it’s melting. The fact that there is any ice, restricts the ocean surface to be near freezing, and the air temperature can likely only go one or two degrees above that. The NP issue was a 50/50 call, and I have no special insight into which way it will go. -gavin]

    I’m surprised at your assertion that the models explain the equally warm 1940s Arctic temperatures. If CO2 is the driver of recent warming, what was driving equivalent or greater warming 90-70 years ago?

    [Response: I didn’t say that above, but you can see what the models can and cannot explain in the figures in the IPCC report. They don’t, in the mean, get quite as much warming in the 1940s as observed – indicating that (assuming the forcings were appropriate) the Arctic peak was likely not a forced response. That leaves either internal variability – possibly associated with the N. Atl. ocean circulation: some models do show excursions of about the right magnitude, or uncertainties in the forcings. Curiously, and I’m surprised you haven’t picked up on this, the maximum black soot deposition in the Arctic was in the 1930s, not today – mostly from US industrial sources. – gavin]

    I can’t imagine why anyone would predict that warming would stop. The earth has been warming for at least 200 hundred years, and the most likely trend is that it will continue.

    [Response: Climate science using only Excel’s linear regression routine! Tyndall would be proud. – gavin]

    Your claim that I have attributed all the warming to soot is incorrect. I never said anything like that, and it is a bit careless on your part to say that I did.

    [Response: You keep implying it, but if that’s not what you mean, try again. – gavin]

    The fact that the models have more recently been adjusted to match empirical evidence in the Antarctic does not negate my point. Events have not proceeded “exactly as predicted” in the 1980s.

    [Response: You are correct. In the Arctic, ice melt is happening faster than predicted. – gavin]

    I’ll have a look at your radiosonde links and respond later.

    Thanks much for your response, Gavin.

  48. 498
    Chris Colose says:

    [Response: Temperatures are cold at the poles. Truly profound. – gavin]

    This had me laughing for a few minutes.

  49. 499
    Chris says:

    #432 Steve Goddard.

    Dishonesty and misinformation do not make for objective analysis!

    This is dishonest:

    Also, you are misrepresenting Hansen’s paper.

    In Hansen Nazarenko 2004, Hansen wrote that “Our estimate for the mean soot effect on spectrally integrated albedos in the Arctic … is about one quarter of observed global warming.”

    i.e. Dr. Hansen said that one-fourth of all global warming (over the entire planet) is due to Arctic soot. The same paper shows the forcing of soot as 2XC02 at 4.05 W/m2 Figure 1 shows Arctic warming of as much as 2-3C due to soot. My statement was completely correct – By any reasonable interpretation Hansen did imply that most of the warming in the Arctic is due to soot.

    In fact Hansen didn’t say what your “i.e….” indicated at all, since your “quotation” of “what Hansen wrote” is a crude and blatant truncation.

    Here’s what Hansen and Nazarenko actually stated (putting back the parts of the sentences you omitted, with your “selection” in italic):

    Our estimate for the mean soot effect on spectrally integrated albedos in the Arctic (1.5%) and Northern Hemisphere land areas (3%) yields a Northern Hemisphere forcing of 0.3 W/m2 or an effective hemispheric forcing of 0.6 W/m2. The calculated global warming in an 1880–2000 simulation is about one quarter of observed global warming.

    James Hansen and Larissa Nazarenko (2004) “Soot climate forcing via snow and ice albedos” Proc. Natl. Acad. Sci. USA 101, 423-428

    So Hansen and Nazarenko are (i) not referring to soot effects on Arctic albedo as you insinuate, but to soot effects on the entire N. hemisphere ice albedo (ii) they are referring to global warming during the period 1880-2000.

    Secondly, if you are interested in representing the science or an individuals research faithfully, you should ensure that you stay abreast of the field. You should note that amongst other things that:

    (ONE) Hansen et al have reassessed the contribution of black carbon on global snow/ice albedo and have “downgraded” the contribution by around a factor of 3 compared to their PNAS paper. So the simulated contribution of black carbon to global warming since 1880 is now 0.065 oC. In other words the total black carbon effect on snow and ice worldwide (not just the arctic) is around (according to Hansen) 1/12 of all global warming since 1880:

    Hansen, J et al. (2007) Climate simulations for 1880-2003 with GISS modelE. Clim. Dynam., 29, 661-696

    (TWO) That while black carbon has a positive contribution to global warming, it is part of the total human atmospheric aerosol load the nett contribution of which is a cooling one. In other words while black carbon in isolation through its effects in the atmosphere and surface is overall warming, black carbon cannot be considered in isolation from all the other atmospheric aerosols.

    So while black carbon has contributed to Arctic ice melt/warming to some extent, the overall cooling effect of our aerosolic emissions has contributed to Arctic cooling. It would be nice if we could selectively eliminate “soot” from our emissions, but “soot”/black carbon is a product of combustion processes that release a cocktail of aerosols the nett effect of which is a cooling one.

    This is discussed in detail in a recent review:

    V. Ramanathan & G. Carmichael (2008) Global and regional climate changes due to black carbon; Nature Geoscience 1, 221-227.

    In their Table 2, R&G diagram the contributions from various man-made greenhouse gas (GHG) and man-made aerosols, considering the effect on both the atmosphere or surface:

    all GHG’s (CO2, methane, N20, halons, ozone):
    atmosphere +1.4
    surface +1.6
    total +3.0 (W/m2 presumably)

    atmosphere +1.0
    surface +0.6
    total +1.6

    black carbon (BC):
    atmosphere +2.6
    surface -1.7
    total +0.9

    non BC man-made aerosols:
    atmosphere +0.4
    surface -2.7
    total -2.3

    There is uncertainty in the precise local and global contributions of these warming and cooling forcings. However if one is interested in presenting what the science indicates, one needs (a) to be honest, (b) to stay abreast of the field and (c) to consider the whole story…

  50. 500
    Ray Ladbury says:

    Rod, re 452, actually I believe I make a pretty concerted effort to ensure that what I know is, in fact, so. As you have in the past not hesitated to ask me questions, I presume that you do not disagree to vigorously with this characterization. Also, when someone shows me that I am wrong, I usually thank them for their efforts. This is one reason why I am still happily married.
    As to anthropogenic causation of the current warming epoch, I’d be more than happy for somebody to show me I am wrong or even that there remain significant doubts. Unfortunately, all of the evidence, as represented by peer-reviewed studies, points toward the inescapable conclusion that we are to blame. When the evidence and the physics agree, it’s hard to retain serious doubts.