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  1. Why don’t you mention the clathrate gun?
    Also we can already see an uptake in methane output ie. siberia. And why is the reason for the PETM warming so importend? This process can be established by temperature rise.

    Comment by savegaia — 10 Aug 2009 @ 7:24 PM

  2. This sort of denialist literary cherry picking (to go with data cherry picking) increasingly reminds me of the kind of movie promotion which takes a review by Woody Allen that says “This movie is such utter rubbish that in order to turn it into a great movie you would have to have a different cast, director, cinematographer and script writer, and even then it would remain perhaps the worst movie made in the history of movie making, whatever you do, don’t go to see it” and publishes a poster saying ‘Woody Allen “Great movie”‘.

    Comment by David Horton — 10 Aug 2009 @ 7:45 PM

  3. Good post–

    I was really surprised when I read this paper and then I found a few commenters posting on my site asking me to explain the quote “There appears to be something fundamentally wrong with the way temperature and carbon are linked in climate models” (e.g., this one). This came right after Zhengyu Liu of Wisconsin-Madison posted a comment saying that the magnitude of large-scale climate changes can be modeled well, although he was referring to a much different event. My impression is that the quote was the only thing certain people read in the news releases, but I must admit I feel it was rather sloppy on the side of Dickens. But it is indeed a bit concerning that there’s still no evidence of a very low sensitivity as proposed by Lindzen, Spencer, etc in the paleoclimate record (quite the opposite perhaps).

    On the other hand, there’s a lot of caveats in this kind of topic that should make one wary of applying it today’s climate change or saying things like “what was really being said was that climate sensitivity is probably larger than produced in standard climate models.” There’s also been a few other misconceptions on other sites about this or similar papers worth elaborating on, even by commenters emphasizing that feedbacks are underestimated:

    — There is a big difference between radiative feedbacks and carbon feedbacks. Today, the radiative forcing from greenhouse gases is well constrained since concentration can be measured to high accuracy for CO2, methane, ozone, etc which is not the case for deep-time equable climates. In the PETM, it is likely that a majority of the warming which exceeds the expectations from just the direct CO2 forcing was a carbon feedback (which would be easily picked up today) and not directly related to changes in cloud cover, water vapor, etc where it is more difficult to contrain the magnitude or sign of the amplification/dampening.

    — The timescales relevant to anthropogenic climate change are such that we probably don’t need to worry about large, de-stabilizing carbon feedbacks such as methane release from the sea floor unless emissions continue to go unabated for a long, long time. And, it’s probably still the best option to use the Charney or even transient sensitivity for anthropogenic timescales, unlike the PETM. I don’t want to to discount the response occurring several hundred years in the future to a climate stabilized at, say, 500 ppmv but I wouldn’t try to adopt the slow-feedback-included sensitivity too much in policy settings.

    — As gavin mentioned, you also have to be really careful about using the current linear relation between forcing and temperature as it may eventually break down as temperatures move far enough from the current climate (either for Charney or longer-term timescales), something discussed in Colman and McAvaney (2009), Geophysical Research Letters.

    Comment by Chris Colose — 10 Aug 2009 @ 7:54 PM

  4. Typo: in para 2, &gt 3 should be > 3 (add semicolon after &gt).

    Comment by Matt Andrews — 10 Aug 2009 @ 8:46 PM

  5. Gavin:



    Comment by Steve Fish — 10 Aug 2009 @ 8:50 PM

  6. After that paper came out, I attempted to compile a set of links to resources about the event. Goes all the way back to “ocean burps”.

    Resources on the Palaeocene-Eocene Thermal Maximum

    Comment by Oakden Wolf — 10 Aug 2009 @ 10:12 PM

  7. Maybe we can link methane takeup during PETM to methanogenesis?

    Nickel isotope may be methane producing microbe biomarker
    ‘Our data suggest significant potential in nickel stable isotopes for identifying and quantifying methanogenesis on the early Earth,’

    Comment by savegaia — 10 Aug 2009 @ 10:27 PM

  8. I need a term for this. Any ideas?

    There is:

    1) Science (where this one started).

    2) Pseudo-science (trying to get something really silly accepted as science).

    3) Anti-science (or agnotology): trying to make some knowledge disappear (and some of that is was going on as well).

    4) But I need a term like non-science, or fuzzy-science, or miscommunicated-science, or ???? to describe what happens when one:

    a) Starts with real science.

    b) Either the originators, or those who write the press releases, ascribe higher significance to the results, over-interpret, or mis-state them (often accidentally).

    c) It gets progressively mangled/confused as it flows through various media.

    I think of this as the dust inherent in a (science) construction site, as opposed to a smog-generator trying to hide the site from view.

    But, is there a generally-accepted term, or can people argue for one?

    Comment by John Mashey — 10 Aug 2009 @ 10:45 PM

  9. If Gavin will allow a couple of asides
    — some notes on the press release cluster*ck:
    with a pointer to

    (I wonder if the _third_ author’s press office ground out a release, or only those two, which are the two that Gavin mentions)

    But enough about the need for better press officers, that’s established.

    Gavin, I wonder if the three authors are just keeping their heads down.
    I’d sure like to hear what they think; anyone seen anything?

    Having looked at the Moana site, there’s a huge collection of interesting work there.

    I grew up knowing the difference between limestone and dolomite, helped a geologist map our county based on that among other things (before continental drift was accepted — all synclines and antisynclines — but we got the rock boundaries clear enough to map the county geology.

    Learning that that difference between limestone and dolomite marks the time and depth where ocean water changed from forming shells to dissolving shells — makes one sit back.

    One of Zeebe’s colleagues has a good page on a model of the chemistry (just happened on it; can’t evaluate it compared to others, but very readable):

    Page to the bottom of that if you want to skip the chemistry and read the consequences.

    Comment by Hank Roberts — 10 Aug 2009 @ 11:09 PM

  10. 4) But I need a term like non-science, or fuzzy-science, or miscommunicated-science, or ???? to describe what happens when one:

    a) Starts with real science.

    b) Either the originators, or those who write the press releases, ascribe higher significance to the results, over-interpret, or mis-state them (often accidentally).

    c) It gets progressively mangled/confused as it flows through various media.

    Sigh … you’re looking for “denialism”, because it’s much more sophisticated or subtle (sometimes) than it was a decade ago ….

    Comment by dhogaza — 10 Aug 2009 @ 11:13 PM

  11. For John Mashey — a word for the Rice press release and its consequences?

    Is there a word in baseball for a pitch so bad it humiliates the team, injures a teammate or two, and maybe even gets the pitcher fired?

    Heck, you could call the Rice press office and ask them what _they_ called it.
    (Or call the Moana press office, who did a much better job a few days later and were mostly ignored).

    Or there’s Tom Wolfe’s phrase:

    Comment by Hank Roberts — 10 Aug 2009 @ 11:24 PM

  12. John, how about “garbled science”? There may also be room in your taxonomy for “spin science”…

    Comment by coby — 10 Aug 2009 @ 11:58 PM

  13. Your new format is 3/4 inch too wide for my monitor.

    In the Eocene, when the methane suddenly erupted from the clathrates, were there fuel-air explosions? In “Six Degrees” by Mark Lynas, he predicts fuel-air explosions from that very source as one of the extreme kill mechanisms. “Worse than a nuclear war,” he says. How would you find the concussions/blast effects in the geological record? Do you find fossil evidence of fuel-air explosions? It seems to me that there should have been fuel-air explosions. I know from the fact that the Department of Defense finds fuel-air bombs to be “effective” that many animals would be killed by such a blast. Could anybody elaborate? Some of the methane would oxidize in a more gradual way, catalyzed by sunlight?

    A paleontology graduate student told me that most of the extinctions from the PETM happened at the end of the event, when the Earth cooled back down. Could you comment on that?
    What was the Earth like during the PETM? I heard something vague about swampy forests everywhere. Could anybody elaborate? I take it that most humans would not like that kind of climate.

    Comment by Edward Greisch — 11 Aug 2009 @ 12:00 AM

  14. Another excellent post from RealClimate.I’m an amateur climate guy who prides himself on having read most all the climate news since 1987.I graduated Harvard College, and Boston College Law school,liscenced to practice law in Massachusettes, and teach in public schools here in San Francisco.I’m a liberal Democrat environmentalist who sometimes blogs my humble opinions on DeSmog Blog or RealClimate.
    I’m going to say a few things.First, if you think that the methal hydrate outgassing from the seabed floor is nothing to worry about in the short term then that is a huge mistake.Next, the peat moss in Siberia will outgass.The three feedbacks that Gavin talk about in the PETM will also converge on us.The currents that cleanse the Arctic ocean have already started their shift.Remember that if the North Atlantic current driver, the salinity levels off Greenland, continue to change with the freshwater melt, then the North Atlantic current could shut down.This article on the PETM exactly show the complete folly of underestimating the radiative forcing of an increase in methane.Some believe the outgassing in that era was well above 3000 GtC.Such an outgassing (even less),in the 22nd century could easily push co2 levels to stabilise well about 1000 mmp, for many centuries.The methane will stay around long enough to force a logarithmic increase in temperature.See the record for 55 million years ago.That is right in the article, people!Hansen once again has it correct.The CUMULATIVE OUTGASSING AND CUMULATIVE AMPLIFIED RADIATIVE FORCING is what we need to look at when examining any Earth based system.So, we need to include,(not a complete list by far), the melting of sea ice(loss of albeido effect), the outgassing from the peat mosses,the cascade effect on the drying of the Amazon, increased earthquakes and volcanic activity due to loss of pressure on the land masses from loss of sea ice tonnage,release of co2 as forests increase their massive die off, and, most importantly, the loss of the ability of the oceans to take up and bind co2 as they become even more acidic and saturated with co2, and, God forbid, the QUITE POSSIBLE RELEASE OF MEHTAL HYDRATES CURRENTLY CAPPING METHANE ON THE SEABED FLOOR.The changes are cumulative, logarithmic, and FEED on each other.That is exactly the lesson we can learn from examining the PETM data in this article. It may as well be a simple roadmap for anyone to see.The fact that the press got it wrong and told the exact opposite message and that the news outlets picked up on this incorrect message is what usually happens when scientists’ messages get distorted.See De Smopg blog(everything they’ve ever done) for clarification, if you need to.You know it as well as I do. The people who twist the message backwards simply do not have the capacity( or the political will) to understand what the scientific paper said.The press release on this scientific article made it appear that there is less to worry about with global warming.Actually, if you read the paper, the message to the world should have been that there is way, way more to worry about. If such a large event happned at the PETM, there is no logical reason to assume it cannot happen again.Actually, the default logic should be that if happened before, then it could happen again.Once again, I’ll say it. 1000 mmp,starting about year 2200, for a few thousand years.Feedbacks grow on each other, folks.End of story.You know, if one little extra fracture in an earthquake zone due to the change in pressure from loss of sea ice were to start an otherwise inactive volcano, THAT ALONE MIGHT BE ENOUGH TO QUICKLY MELT THE METHANE ICE, by the year 2200.With all the cumulative, logarithmic, feedbacks in play that are listed above, the levels could rise well above 1000 ppm, and stay there,just long enough,to secure the Anthropocene’s place in geologic history as the sixth major Epoch.Our history as a species, however, is quite another story.What type of a world do we want?And, did not some great writer say something to the effect that if we let fools govern us while the smart people stay home and sit on the sidelines then we get what we deserve, or something to that effect?As I leave you for the evening let’s hope that one volcano stays unlit.Hoping for success at the December, 2009, Copenhagen talks, but it does not look good.One more little thing.The oceans are almost at their carrying capacity.What if the capacity is lower than expected, as some experts believe, and the ocean itself starts to release co2?If it starts a chain reaction with a release of co2 stored in the actual seabed rocks then that is also it, folks.I’ll say it again.The song goes like this.”1000 ppm, 1000 ppm, 1000 ppm.”
    Mark J. Fiore

    Comment by Mark J. Fiore — 11 Aug 2009 @ 12:05 AM

  15. #8 John Mashey

    How about ‘Spin-Cycle Science’

    Comment by John P. Reisman (OSS Foundation) — 11 Aug 2009 @ 12:46 AM

  16. Re #8

    Isn’t there already a term? Confirmation Bias – only seeing what you want to find.

    Comment by Mike Coombes — 11 Aug 2009 @ 12:51 AM

  17. “we probably don’t need to worry about large, de-stabilizing carbon feedbacks such as methane release from the sea floor”
    Methane is already bubbling out of the Arctic ocean and out of tundra peat bogs that have melted and turned into lakes.

    Comment by Edward Greisch — 11 Aug 2009 @ 1:06 AM

  18. Regarding new terms for confusions, and linking partly to the earlier ‘Unscientific America’ thread, I think we need to start even more fundamentally – with the misconception that politically funded ‘science’ is real science at all, unlikely to ever do much more than make sure that science lines up correctly behind politics.

    Comment by Rene — 11 Aug 2009 @ 1:59 AM

  19. Personally this paper and its resultant headlines in the media might smell of getting additional interest in the paper itself, which seemed to succeed or in the medias constant fascination in the debate on the subject of climate change and the vested interest that some media outlets have in putting doubt into peoples minds about doing anything about it by denying it is even happening.

    The computer models are the area that the deniers attack the most (where the most laymans doubt lies) and hence the headlines promote this area of headline. Personaly I cannot understand how the academic establishments linked to the paper in question are being too pushy with their headlines. They understand the scientific process surely and should understand the media input into these papers. Peer review is not the truth, its just more likely to be true at this point and hence worth reading by scientists in the field.

    Someone needs to sort out the marketing/media departments when it comes to reporting science to the media. Too many mistakes are being made.

    Comment by pete best — 11 Aug 2009 @ 4:50 AM

  20. Fascinating stuff. What a pity we have to hear about it filtered through fending off denialist garbage. A real pleasure to read this article after being subjected to repeated application of the Dunning-Kruger effect at my local newspaper’s online forum.

    #8: John Mashey: this reminds me of the broken telephone game, where kids whisper a message to each other, then the last in the chain says the “message” out loud, usually totally garbled.

    Comment by Philip Machanick — 11 Aug 2009 @ 6:03 AM

  21. Re #14, I cannot read all of the post but from what I have read of it you have to put it into context in regard to todays world. Antartica was physically where it is now (pretty much) 55 million years ago but it was not frozen over and neither was the Arctic (I am assuming) meaning that sea levels would have been a lot higher than today. This would change the sensitivity of the earth to what was already a warm world (far warmer on average than todays) and the carbon cycle would not be the same as in todays world.

    The Antartic began to develop ice sheets around 34 million years ago and the Arctic as early as 3 million. The worlds CO2 levels 34 million years ago was between 425-475 ppmv and the Arctic lower still (perhaps as low as todays level of 390) hence its present summer time Greenland and Sea ice melting. Antartica and Greenlands present more unstable conditions seem to indicate that we have entered the area of CO2 where melting is occuring and not recovering in the winter sufficiently to regain that lost mass or the process of ice sheet loss at the edges. The poles as we appreciate them now have 100 ppmv of CO2 warming to contend with and some of them will be lost.

    The senistiivty of arctic permafrost defrost and other emissions from that part of the world will probably ineviatably accelerate warming in the future but the question is how much melting has 390 ppmv committed us too. A lot of I would suggest and hence a lot more permafrost issues.

    Comment by pete best — 11 Aug 2009 @ 6:38 AM

  22. Re. 20:

    Chinese whisper Science. I like that!

    Comment by S2 — 11 Aug 2009 @ 6:55 AM

  23. Excellent post.

    The perils of journalism covering science.

    Comment by seb — 11 Aug 2009 @ 7:10 AM

  24. #8: John Mashey – how about “second law” science, where there is an inevitable *increase* in entropy with time and spread of the findings.

    Comment by Adam — 11 Aug 2009 @ 7:26 AM

  25. As Steve Fish says, wow! I happened to be looking at a Richard Feynman lecture yesterday. Gavin has more of that marvellous ability to expound than most of us can dream of.

    Like Mark Fiore, I am an amateur in the field who has been reading the stuff for twenty years. Neither he nor I can have any sensible idea of where nor when this climate warming episode that we are in will end up; and less about its likely duration. Nonetheless Hansen’s informed uneasiness about apparent amplifying effects in past global warmings seems to be acquiring more and more findings which are congruent with it; and, worse, damn all that falsifies his hypotheses. As I read these PETM tentative findings: if release of ground methane is a powerful driver, then it may be massively released from stores which do not depend upon Arctic cold, as well as from those that do. Not a comforting thought.

    Comment by David Heigham — 11 Aug 2009 @ 7:41 AM

  26. “The Antartic began to develop ice sheets around 34 million years ago and the Arctic as early as 3 million.”

    I think you mean *permanent* ice sheets.

    It developed winter ice a lot longer than that ago.

    Comment by Mark — 11 Aug 2009 @ 7:48 AM

  27. Re #26. I have a chart that I cannot post here due to it being seen as spam but its a BAS chart of ice sheet formation putting the first Antarctic permanent ice sheet at 15 million years ago and the Arctic/Greenland ones at 3 million so I cannot see you logic if the Greenhouse world only finished when the first polar ice sheets formed (not permanent) 34 million years ago.

    Comment by pete best — 11 Aug 2009 @ 8:44 AM

  28. “very singular” – seems to me it is either singular or it is not

    a minor quibble on an excellent post

    Comment by David Wilson — 11 Aug 2009 @ 9:14 AM

  29. RE: Media manipulating a story to suit their own purpose.

    I would suggest any time the ADD afflicted media gets involved the message gets garbled.

    This happens on either side of the debate and is probably the biggest reason the science has yet to be settled (and it is not – please don’t call those that are still
    searching for answers know nothings – I am an MSc. Engineer, trained, as are all engineers, in the method of synthesis for problem solving and work in the field of Quantified Risk Assessment).

    If there were still such a thing as investigative journalism, the opposite of ADD journalism, some of the climate model predictions would have been outed for not stating the uncertainty associated with their input assumptions. Perhaps then we could have more reasoned discussion on possible CO2 contribution to the Earth’s greenhouse effect and reach a more logical consensus on where we should be directing policy.

    A poem from Stephen Leacock comes to mind: “He flung himself from the room, flung himself upon his horse and rode madly off in all directions” It seems to me the policy decisions are a bit like that and not as much based on sound, reasoned decision making, as I am used to using in my own field of work.

    Comment by Doctor K — 11 Aug 2009 @ 9:33 AM

  30. “please don’t call those that are still searching for answers know nothings”

    a) they do know nothing. Then again, it isn’t EXPECTED they would know about this. Climate is *hard*. So stop making “you know nothing” a bad thing. The bad thing happens when someone who knows nothing thinks they know a lot.

    b) while they search for answers, they are know nothings but that isn’t a problem (see above). However too many “searchers” are searching for a way to deny the science. Denialists who call themselves skeptics are not “searching” for answers, they’re wasting time and won’t change their mind about AGW no matter what is presented. Why is it not OK to diss those who are sham skeptics?

    Comment by Mark — 11 Aug 2009 @ 9:41 AM

  31. Pete Best (#27) The Antartic was ice bound in winter before the Triassic (unless you want to claim “Walking With Dinosaurs” incorrect). Episode 4, IIRC.

    Comment by Mark — 11 Aug 2009 @ 9:43 AM

  32. The ‘more specific’ headline proposed: ”Global warming: Our best guess is likely too small”

    seems to be at odds with the Zeebel, Zachos and Dickens conclusion:

    “We conclude that in addition to direct CO2 forcing, other processes and/or feedbacks that are hitherto unknown must have caused a substantial portion of the warming.”

    If CO2 sensitivity, as currently understood, is not enough to explain the PETM, one response would be, indeed, to raise that sensitivity in the models. It would appear, though, that the authors do not propose such a response, and so a headline saying “warming guess too small” would not match up with this particular study very well. Perhaps I misunderstand the proposed headline.

    [Response: Almost certainly. -gavin]

    Comment by Walter Manny — 11 Aug 2009 @ 9:53 AM

  33. In identifying attacks on science, we should recognize as a category the attack on statistics (or should I say probability?). This is I think a part of the attack on the concept of modeling of climate, but it extends well outside of the AGW. We’ve seen it wrt the census as well. And I’m not talking so much about fitting techniques as attacks on the underlying concept. I think it is one that finds support among the public who see it as guessing when there isn’t any “real” proof.

    Comment by Dean — 11 Aug 2009 @ 10:08 AM

  34. Gavin, “almost certainly” what?

    Comment by Walter Manny — 11 Aug 2009 @ 10:10 AM

  35. “Perhaps I misunderstand the proposed headline.

    [Response: Almost certainly. -gavin]”

    One would presume.

    Comment by Mark — 11 Aug 2009 @ 10:24 AM

  36. pete best: “Someone needs to sort out the marketing/media departments when it comes to reporting science to the media. Too many mistakes are being made.”

    These are hardly mistakes. In reality, you are looking at a situation where coal-fired electric utilities, coal railroads, coal companies, and a host of related firms are all bent on rolling back climate legislation that would impact their operations in places like Canadian tar sands fields. The largest group is ACCE, which was just caught sending forged letters to Congressmembers as part of their campaign:

    “The American Coalition for Clean Coal Electricty (ACCCE) has led efforts to perpetuate the myth that coal can be clean. Now it turns out they are responsible for forging opposition to a strong climate bill.

    According to E&E News, the American Coalition for Clean Coal Electricity (ACCCE) is the culprit responsible for hiring Bonner & Associates, the DC-based firm busted late last week for forging letters – ostensibly from NAACP and a Virginia network of Hispanic groups – opposing the US House climate bill (ACES.)

    These are the same tactics used previously by the tobacco industry in their decades-long effort to hide the link between cigarettes and cancer. They’ve been adopted by several other industrial sectors – but look at the list and ask how many of these you’ve seen:

    The TobaccoWiki article about tobacco industry PR tactics describes time-tested corporate PR strategies, like commissioning favorable research, reframing the debate onto more advantageous terms, fostering public confusion, changing the focus of the issue, broadening the issue, staging fake “grassroots” uprisings, generating controversy where there really is none, manipulating the media and legislators, undermining science, creating phony economic statistics, inducing fear among the public and harassing and intimidating opponents, to name a few.

    In this case, blaming it on the Rice press release seems difficult – because the first paragraph contains the sentence:

    “The study, which appears in Nature Geoscience, found that climate models explain only about half of the heating that occurred during a well-documented period of rapid global warming in Earth’s ancient past.”

    That’s a little like the climate model’s underestimates of summer Arctic sea ice retreat – so the misinterpretation and respinning should be obvious. The fact here is that the fossil fuel industry has run out of scientific arguments – and they can’t commission favorable research, because every effort has been a failure. All they are left with as a tactic is distorting the work of real scientists.

    To do this, they need the help of those public relations and corporate media outlets who are willing to print what they want them to print. Is it really plausible to assume that media employees only read the headlines of press releases before writing stories about them?

    What you have here is a deliberate effort to interject doubt into the scientific discussion, nothing else. Of course, the press release should have been titled: “Global Warming: Our Best Guess is Likely Too Low.”

    However, here is the list of distorting sites running with the distorted story – and this is just sites that Google declares to be news sources:

    *Doyle Rice, by the way, also is portraying the low temps in July in the northwest as “a problem for global warming proponents”: – but he doesn’t discuss the atmospheric moisture paper below, and his only sources? Spencer and Christy. USAToday is owned by Gannett Inc., one of the largest corporate media combines. Their shareholders are heavily invested in fossil fuels as well as media, so no surprises here.

    It’s beyond ridiculous – especially for a PR industry that previously made temperature and CO2 reconstructions over the past thousands of years the centerpiece of the denialist message, i.e. the “hockey stick” attacks.

    In actuality, you have a study that seems to predict increased warming relative to what climate models predict – it’s surprising that the study itself wasn’t attacked – but what respected scientist could the PR industry rely on to do that? No one, right? Thus, they simply tried to respin the study.

    You can see that this is deliberate press bias by looking at the kinds of studies and press releases that get little or no press mention, compared to the ones that do:
    “Spectacular Melting Of The Largest French Glacier”
    “Psychological Factors Help Explain Slow Reaction To Global Warming”
    “Climate Models Confirm More Moisture In Atmosphere Attributed To Humans”
    “Ozone Depletion Reduces Ocean Carbon Uptake”
    “Long Debate Ended Over Cause, Demise Of Ice Ages? Research Into Earth’s Wobble”

    Denialists might want to try respinning that one, as it talks about how solar changes initiated the ice age, but before you get your hopes up too much:

    “Solar radiation was the trigger that started the ice melting, that’s now pretty certain,” said Peter Clark, a professor of geosciences at OSU. “There were also changes in atmospheric carbon dioxide levels and ocean circulation, but those happened later and amplified a process that had already begun.”

    I suppose if you hacked off the first part of the sentence, and prefaced it with a headline like “Sun, not CO2, drives historical warming”, well, you’d be on your way…
    “Researchers Reveal Ocean Acidification At Station ALOHA In Hawaii”
    “Highest Ever Winter Water Temperatures Recorded Off Tasmania”
    “Global Ocean Surface Temperature Warmest On Record For June”

    Those are all press releases from the period July 27 to Aug 9, alone. How many of them have received similar press coverage by USAToday or any other major U.S. press outlet?

    Comment by Ike Solem — 11 Aug 2009 @ 10:25 AM

  37. Mark, re. “So stop making “you know nothing” a bad thing”

    I was merely referring to the original context of the term used in
    this thread. I was not the one who made the term a bad thing.

    Mark, re. “The bad thing happens when someone who knows nothing
    thinks they know a lot.”

    I believe this is an accurate statement and applies to both sides
    of the debate (and obviously varies greatly depending on the individual).
    We collectively do not know a lot about this issue,(hence the
    numerous unsubstantiated assumptions in the climate models) so we are
    all collectively guilty of thinking we know a lot. It’s hard for all!
    But the scientific method will eventually weed out the theories from the facts.

    Here’s to more open discussion of the various theories (and less name calling)
    and hopefully good policy as a result.

    I just wish the media could set the objective agenda rather than go for the ADD fluff.

    Comment by Doctor K — 11 Aug 2009 @ 10:26 AM

  38. Re #31, Did the Antartic exists 200 million years ago? Not acording to the Wikipedia Map of the triassic period.

    Are we talking at cross purposes here. Cant eliminate the fact that in its present state when the PETM (55 million years ago) happened Antartica was ice free as was the rest of the world. 19 million years later with the oceans temperatures falling ice formed.

    Comment by pete best — 11 Aug 2009 @ 10:53 AM

  39. Re #36, If indeed proxies (funded by fossil fuel companies) released data and press releases deliberately misleading the evidence and indeed being propaganda in nature then fair enough and quite typcial of the US system where lobyists and funding obfuscate the truth. It very much sounds like the outbreak of numerous ludicrous statements surrounding the health change reforms Obama wants to introduce.

    Thanks for the post.

    Comment by pete best — 11 Aug 2009 @ 10:57 AM

  40. Re #8

    How about “Town hall science”, where the one who shouts loudest wins?

    Cheers, Alastair.

    Comment by Alastair McDonald — 11 Aug 2009 @ 11:13 AM

  41. Before PETM, the oceanic bottom waters were as warm as 15°C ; you need to put the event in the global cooling history which began in Paleocene times; an image would be you turn the ocean upside down, and bring to surface heat and all the biogenic Carbon stored in deep waters; the big biologic change that happened at the surface at the K/T limit, happened in the benthic world at the PETM due to cooling of deep waters and starting of the thermo haline circulation, all that having nothing to see with the climatic sensitivity of the CO2

    Comment by frederic — 11 Aug 2009 @ 11:16 AM

  42. There seems to be a need for a whole terminology to deal with the kinds of science reporting you are describing.

    I like “spin-cycle science”, but it doesn’t get to the root of the intentionally misleading reporting and the vicious personal attacks that result. “Chinese whisper science” also lacks the intentional nature of the misleading reports.

    I can get a bit closer by defining two new terms. How about “Corrupted Reporting on Anti-Science Slogs” with the acronym CRASS. A “slog” would be a blog dedicated to CRASS commentary, particularly encouraging slurs against real scientists.

    In general use, we could see statements like “The XXXX site is considered the most popular slog on the internet, with hundreds of CRASS posts annually. Generally the CRASS posts take original source information, and edits the report along with adding a new title and commentary that better suits the views of the slogmeister ZZ. A lack of relevant scientific qualifications or competence is a common feature among the most well known slogmeisters.”

    Try replacing XXXX with “WUWT” and ZZ with “Anthony Watts”, or alternatively “Climate Depot” and “Marc Morano”, to see how that reads.

    Comment by Paul K in Seattle — 11 Aug 2009 @ 11:46 AM

  43. “I was merely referring to the original context of the term used in this thread. I was not the one who made the term a bad thing.”

    No, if you didn’t mean to consider it a bad thing, you wouldn’t be complaining about it.

    Who complains about people being called “upstanding” or “honest”?


    “Dishonest” or “weaselly” yes.

    “I believe this is an accurate statement and applies to both sides of the debate (and obviously varies greatly depending on the individual).”

    A true but purposeless statement.

    After all “being unpleasant to people they don’t like” is something the allies and the Nazi powers had in common.

    Kind of cheapens the point, doesn’t it.

    Which is because it’s a purposeless statement. It adds nothing and helps nothing, producing no discernible change or direction.

    Comment by Mark — 11 Aug 2009 @ 12:06 PM

  44. Hmm–how about a geological analogy for that elusive word for “mangled science?” According to this paper’s abstract, “estimation error increases as the heterogeneity of the rock mass increases.”

    Substitute “information” for “rock mass” and you get the term “heteroscience.” I suppose it’s potentially subject to misinterpretation, but to me it has a suitable Latinate vibe.

    Comment by Kevin McKinney — 11 Aug 2009 @ 12:09 PM

  45. Doctor K: mentions “numerous unsubstantiated assumptions in the climate models”.

    Such as?

    Comment by Jim Galasyn — 11 Aug 2009 @ 12:17 PM

  46. Re: pete best: You are being one-sided.

    First, Generally the titles of an article are not written by the reporter / writer, they are put on by the editor. His/her job is to sell papers, or content, or bring in readers so they jazz it up.

    This works both ways. How many outlets carried the NOAA LOWERING it’s hurricane forecast for this season? How many made it front page news? Because they sure do carry the headlines when there is an increase in the forecast.

    Google Antarctic warming and you’ll see the Steig paper covered by the NY Times, USA Today, MSNBC, the list goes on and on. Then Google antarctic warming corrigdenum and let me know what you see.

    You guys have the media’s ear, they are all listening to you, publishing your studies, and covering all your papers. They publish them without question.

    It’s only a small percentage of the media that bothers to cover anything counter to AGW theory, it tends to be fringe coverage at best, and it’s surprising to believe you could be so bent out of shape by it.

    Comment by D Robinson — 11 Aug 2009 @ 12:41 PM

  47. Another suggestion for John Mashey:


    “Public relations was about fashioning and projecting credible renditions of reality itself.”

    From Ch. 1 of:

    PR!: A Social History of Spin
    By Stuart Ewen
    ISBN: 0-465-06168-0

    Much else good there, worth a look.

    Comment by Hank Roberts — 11 Aug 2009 @ 1:12 PM

  48. It’s unfortunate that some are peddling the wrong message from the cited paper.If the sensitivity numbers are larger than the current ones given by the IPCC, it’s all the more reason for taking action.

    Carbon dioxide forcing alone is also not the only agent affecting warming today. We,of course have methane et al contributing to the problem. The fact that a University is responsible for the misinformation that ‘…Our best guess is likely wrong’ makes the release all the more troubling

    Comment by Lawrence Brown — 11 Aug 2009 @ 1:14 PM

  49. On your horse, Mark…I’m done with your attitute on this blog…

    Jim. I will do some research and get back later with my findings.

    Comment by Doctor K — 11 Aug 2009 @ 1:20 PM

  50. Am I correct that “There is global warming on Mars” is due to some press officer spicing up a press release?

    Comment by Theo Hopkins — 11 Aug 2009 @ 1:54 PM

  51. I think the title was an unfortunate choice and made it easier for it to go the wrong way, but it would have likely gone that way anyway as certain people are chomping at the bit for new information they can spin out of context.

    In celebration of the latest deni alist drama I finished a new page I have been playing with.

    this compliments of course an old classic

    and my favorite

    As always, any contextually relevant comments are appreciated if it looks like I am misrepresenting things.

    Comment by John P. Reisman (OSS Foundation) — 11 Aug 2009 @ 2:18 PM

  52. #8 – another vote here for “spin cycle science”. I’ll also suggest “overspun science”.

    I have a proposed (partial) solution to this problem: major universities siphon off a percent of their PR budgets to create an independent, nonprofit, scientific press office. That office puts out its own press releases for papers produced by member universities. The arms-length relationship will produce more honest releases and headlines, ones that also clearly delineate when the author is talking about the paper’s conclusions and when, as in Dicken’s case, the author is speculating beyond what reviewers allowed.

    The advantage to universities (aside from trivialities like Truth, etc.) would be perceived greater credibility of the resulting press release.

    Comment by Brian Schmidt — 11 Aug 2009 @ 2:23 PM

  53. > global warming on Mars

    Theo, that’s #16: Mars is warming

    Comment by Hank Roberts — 11 Aug 2009 @ 2:57 PM

  54. D Robinson wrote: “It’s only a small percentage of the media that bothers to cover anything counter to AGW theory, it tends to be fringe coverage at best …”

    Do you consider The Washington Post and The Wall Street Journal and Fox News and CNN — all of which have repeatedly and prominently presented ExxonMobil-funded denialist propaganda as legitimate “debate” and have for DECADES, until quite recently, given denialist frauds and cranks “equal time” with the world’s climate science community — to be “fringe”?

    Comment by SecularAnimist — 11 Aug 2009 @ 4:08 PM

  55. The many interesting twists to the PETM story tells me that we’re not so sure if its missing feedbacks or missing carbon…

    Methane has taken center stage since the composition of carbon in our atmosphere became very light, very fast during the PETM. There is pretty good evidence that this occurred in a single pulse, in less than 500 yrs:

    There is also convincing evidence that the earth was warming a couple thousand years prior to the injection of light carbon (Slujis et al., 2007, Nature).

    Volcanoes were doing interesting things during exactly 55 Mya (breaking up Greenland from Europe and stuff, Storey et al., 2007, Science) and outgassing from the mantle does not change the carbon composition of the atmosphere…

    So what’s so crazy about more carbon and less feedbacks?

    Comment by Adam — 11 Aug 2009 @ 4:10 PM

  56. I originally posted on the R. Zeebe et al paper as OT on july 17th under the Sea ice minimum forecasts, 43rd.

    Gavin writes: “In fact, the concept we should be looking at is the Earth System Sensitivity (a usage I am trying to get more widely adopted) as we mentioned last year in our discussion of ‘Target CO2‘. The point is that all of those factors left out of the Charney sensitivity are going to change, and we are interested in the response of the whole Earth System – not just an idealised little piece of it that happens to fit with what was included in GCMs in 1979.”

    Science Magazine(31 july 09) has a book review by LR Kump of He Knew He Was Right, The Irrepressible Life of James Lovelock and Gaia / James Lovelock In Search of Gaia by John Gribbin and Mary Gribbin

    LR Kump writes: “Throughout his book, Lovelock decries American science. He refers to the “disastrous mistake” of assuming “that all we need to know about the climate can come from modeling the physics and chemistry of the air in ever more powerful computers.” The geochemists’ box models of global biogeochemical cycles and the atmosphere and ocean scientists’ general circulation models ignore the physiology of a living planet. They assume linear parameterizations where life instills parabolas, with multiple equilibria and sharp transitions from homeostasis to positive feedback and system failure when pressed beyond optima. In Lovelock’s view, American science is too compartmentalized into narrow disciplines, too reductionist in approach, so well funded as to stifle creativity, and too reliant on computer models. Lovelock places higher value on observation and experimentation than on modeling. To understand his perspective, imagine Marcus Welby, M.D., using computer models to generate a prognosis for progression of a serious disease.
    According to Lovelock, America has largely ignored or rejected Gaia theory, a claim that is somewhat difficult to rectify with the Gribbins’ conclusion that it has become increasingly respectable. In Lovelock’s view, Gaia puts American scientists at professional risk. [Indeed, a reviewer of the manuscript of a 1994 paper I coauthored with Lovelock (4) claimed that its publication would likely ruin my career.] He believes that the concept casts doubt on the way science is divided into disciplines, presumably challenging the value of their associated administrative and educational bureaucracies. “Gaia is a holistic concept and therefore unpalatable to rational Earth and life scientists.” As counterpoint, the Gribbins proffer the two American Geophysical Union Chapman Conferences on the topic and the elevated role that Earth system science has played in the scientific assessment of global warming. Yet we American scientists rarely utter the word Gaia except in critique of, or commentary on, these meetings or the writings of Lovelock, Lynn Margulis, and precious few others; Science’s internal search engine reveals no papers where Gaia was used except in this fashion.
    Early in Final Warning, Lovelock rejects CO2 and climate stabilization schemes, referring to them as “no better than planetary alternative medicine.” Here he sees little prospect in alternative and renewable energy or in most geoengineering schemes, with the exception of the burial of intentionally charred biomass (5). Later—perhaps reflecting an evolution of thought during the writing of the book and an expression of the inventor in him—he argues that we now have little option but to try various geoengineering schemes to moderate what he feels are the inevitable dire consequences of “global heating.”
    Do we do ourselves and society a disservice by ignoring Gaia? Are the intuitions of a planetary physician a more accurate prognosis for the future than those produced by supercomputers created by multidisciplinary teams of scientists? Climate scientists acknowledge the uncertainties of their projections and are working diligently to reduce them. But are we properly incorporating the feedbacks between climate and a globally potent biota? And do we even have time to refine these models? Lovelock thinks not. He calls for an immediate shift of focus to adaptation to a hothouse world, expecting that in the coming decades humanity will be forced to migrate to the few habitable refugia that remain (including the British Isles). The world population will be reduced from billions to millions, Gaia selecting those humans with the traits to live sustainably (her revenge). Models might come to serve an important alternative role even in this crisis phase, if and when it comes. Shifting from long-term projections to medium-term forecasting, future models with proper planetary physiology might identify the harbingers of the approach of a climate threshold, and if coupled to an expanded network of Earth observations, do so before it is too late.”

    The Zeebe et al study itself concluded, “… our results imply a fundamental gap in our understanding of the amplitude of global warming associated with large and abrupt climate perturbations,” and that “this gap needs to be filled to confidently predict future climate change.”

    Perhaps Lovelock’s second opinion for our Planet deserves a second look.

    Comment by glen — 11 Aug 2009 @ 4:46 PM


    I found the above site to be the most neutral in discussing climate models.

    1. Cloud representation and convection appears to be poorly understood in the models and seems to be a fairly big contributor to the level of uncertainty.
    2. Model grids and how they are applied at the poles also appear to cause some uncertainty.
    3. Positive feedback contribution of greenhouse gas vs water vapour cannot be very certain until # 1 can be resolved.

    Comment by Doctor K — 11 Aug 2009 @ 4:54 PM

  58. Ike Solem wrote: “
    “Long Debate Ended Over Cause, Demise Of Ice Ages? Research Into Earth’s Wobble”

    Denialists might want to try respinning that one, as it talks about how solar changes initiated the ice age”

    Actually, this was on WUTT last week. After it was pointed out that the title was misleading it was changed from ‘CO2 not involved’ to ‘CO2 not main driver’.

    Coincidentally my comment there was: “This is one of those articles, like the one about the PETM event, that really makes me wonder what it’s doing on WUWT. The comments make for entertaining reading, though. The power of subjective interpretation never ceases to amaze me.”

    Comment by Neven — 11 Aug 2009 @ 4:56 PM

  59. > most neutral
    Checked the history?

    Comment by Hank Roberts — 11 Aug 2009 @ 5:05 PM

  60. Put oil firm chiefs on trial, says leading climate change scientist
    James Hansen, one of the world’s leading climate scientists, will today call for the chief executives of large fossil fuel companies to be put on trial for high crimes against humanity and nature, accusing them of actively spreading doubt about global warming in the same way that tobacco companies blurred the links between smoking and cancer.

    Good Idea!

    Comment by Thomas — 11 Aug 2009 @ 5:10 PM

  61. When, and after this occurred, the planet still had all its coal, oil, natural gas etc, etc reserves still intact. Not so this time.

    Comment by Bogey — 11 Aug 2009 @ 5:42 PM

  62. Doctor K speaks of …

    We collectively do not know a lot about this issue,(hence the
    numerous unsubstantiated assumptions in the climate models)

    And when challenged, returns a list of model issues that are not “unsubstantiated assumptions”.


    Comment by dhogaza — 11 Aug 2009 @ 5:53 PM

  63. Thanks for the follow-up, Doctor K.

    As I’m sure everybody agrees, the models are certainly not “complete,” but they certainly are useful, and improving all the time. But these widely acknowledged deficiencies are still far from being “numerous unsubstantiated assumptions”. To my mind, the assumptions are pretty well substantiated by observation and realized as parameterizations.

    Comment by Jim Galasyn — 11 Aug 2009 @ 5:57 PM

  64. For me it is frustrating that the posts about such findings so often take the form of “look at how this is misinterpreted by climate denier evildoers and ignorant journalists” followed by the predictable complimentary comments.

    Instead, there’s clearly a growing body of reasonably reviewed climate research that is challenging the veracity of existing climate models and some of the prevailing assumptions about natural climate variation.

    Since the AGW hypothesis rests on the assumption that current models account well for natural variations these findings are significant and should be a core concern of any reasonably minded scientific person.

    Rather than dismissing them pretty much out of hand as “inadequate”, “uncertain” or “denialist propaganda” as is generally done here, it would be enlightening to approach ideas that conflict with current models as good food for thought.

    Comment by Joe Hunkins — 11 Aug 2009 @ 6:25 PM

  65. Re:56 “Positive feedback contribution of greenhouse gas vs water vapour cannot be very certain until # 1 can be resolved.”

    Greenhouse gases are a forcing, not a feedback.

    Comment by Lawrence Brown — 11 Aug 2009 @ 6:35 PM

  66. Well, joeduck (Hunkins), your blog claims Realclimate is a place you’ve found

    “personal abuse and reckless pseudo-science”

    Want more of what you always get here?
    Here’s mine again. Brace yourself:

    Citations, please, for what you claim?
    Which papers are you talking about,
    where are you reading about them,
    and why do you consider your source a reliable one?

    Comment by Hank Roberts — 11 Aug 2009 @ 7:02 PM

  67. Another thought for John Mashey:


    or maybe


    See the NYT column On Language:
    How Fail Went From Verb to Interjection

    Comment by Hank Roberts — 11 Aug 2009 @ 7:22 PM

  68. Rather than dismissing them pretty much out of hand as “inadequate”, “uncertain” or “denialist propaganda” as is generally done here, it would be enlightening to approach ideas that conflict with current models as good food for thought.

    Well, then, list those ideas that conflict with current models that are “good food for thought” rather than last year’s (or, in many cases, last decade’s) garbage, and tell us why you think they are.

    Let’s see if you can do better than Doctor K’s epic fail above, when on being asked to list the “unfounded assumptions” built into models returned with a list of things that, well, aren’t assumptions at all, founded or unfounded.

    Comment by dhogaza — 11 Aug 2009 @ 7:25 PM

  69. 29 Doctor K: Uncertainty is a 2 edged sword. It cuts both ways. We can’t prove that global warming Will make us humans extinct in 200 years and we also can’t prove that it will Not make us extinct in 5 years. The climate scientists who run RealClimate are as good at probability, statistics, risk analysis and error bars as anybody, probably better, but you don’t see the hairy math here in this popular level publication. Since most people are allergic to math, they stop reading at the first mathematical symbol. That is why it is necessary to leave the math, especially the really hard math like statistics, out of the article intended for popular consumption.

    Comment by Edward Greisch — 11 Aug 2009 @ 8:00 PM

  70. Joe Hunkins (63) — AGW is not a hypothesis, but a consequence of what is known about Earth’s climate. Essentially all important parts have been worked out some time ago. You’ll see that by reading “The Discovery of Global Warming” by Spencer Weart:

    Andy Revkin’s review:

    Comment by David B. Benson — 11 Aug 2009 @ 8:38 PM

  71. Mostly I have a science question. Why is the arctic amplification expected to be larger in Paleocene time? My semi-naive guess would be that lack (or minimal) snow-ice albedo feedback would greatly reduce arctic amplification. So what other process is overwhelming that one?

    But, a comment on the denialism. Much of it is collective-ad-hominem in nature “those stupid scientists don’t know what they are talking about”. So any claim that we don’t understand climate sensitivity, even if the new data supports more dangerous higher sensitivity, can be used to discredit climate science in general. Once that is done, the precautionary principle can be thrown out the window.

    Comment by Thomas — 11 Aug 2009 @ 8:40 PM

  72. Gavin, to veer momentarily back to the subject you started here —

    You’ve been clear about the many uncertainties of the paleo record before and during the PETM event. Have you tried to lay out an Earth System Sensitivity for that situation? I’d love to see that set side by side one for the current planet.

    I’d also like to see that somehow show the difference in rates of change.
    (There’s more but something’s hitting the spam filter so I’m chopping it here)

    Comment by Hank Roberts — 11 Aug 2009 @ 10:10 PM

  73. Second chunk to test the spam filter:

    For example, we know (or I think) that at the pre-human geological pace, CO2 in the atmosphere changed at a rate slow enough that ocean pH did not change (because it’s taken up by biogeochemical cycles that operate over millenia not decades).
    That’s change at the pace of evolution (with one-year generations).

    Compare that to the present when ocean pH is changing already. Very different situation. We’ll get selection effects, and we’ve got a much deeper archive of genetic variation since the past big extinctions — far more genes are out there even at low frequencies from previous climate excursions, nature doesn’t lose them, so when the next excursion comes those can show up very fast; we’re not waiting for hopeful monsters to evolve to suit a greenhouse warm planet, this time.

    Copepods living away from the continental shelves already evolved, what, 200 million years or so ago? last time around, or was it the time before that …

    Even though there may be genes available to be selected by changed climate, that works only at the population level (luckily organisms with a planktonic stage can spread fast!) — but for an ecosystem, timing problems show up at current rapid rates of course, e.g.
    “… many species are becoming mistimed due to climate change. We urge researchers with long-term datasets on phenology to link their data with those that may serve as a yardstick, because documentation of the incidence of climate change-induced mistiming is crucial in assessing the impact of global climate change on the natural world.”

    I know much is beginning to be done with the biological cycling — I saw a paper by Dr. LeQuere mentioning that plankton researchers have many records of relative frequencies of species at various locations and times, contemporary and paleo, and that these ought to be made more easily available to modelers.

    Dr. LeQuere has been arguing with other plankton folks for some years about the need to begin incorporating what we know into models sooner than later, e.g. (certainly not the latest word, just what I found easily)
    Reply to Horizons Article ‘Plankton functional type modelling: running before we can walk’ Anderson (2005): I. Abrupt changes in marine ecosystems?

    Plankton Functional Types in a New Generation of Biogeochemical Models
    C Le Quéré, S Pesant – Eos Trans. AGU, 2009 –

    If it makes sense as an extended exercise — I’d really like to see or help with an attempt to lay out an Earth Systems description side by side for contemporary and PETM conditions, error bars and all.

    Comment by Hank Roberts — 11 Aug 2009 @ 10:16 PM

  74. This is more than an issue about public relations, press releases, and what to call ‘science’ that is not science. This is about an absolute crisis-level need to educate the public. Please let’s not use the term “know-nothings”. It is incredibly demeaning, and can be viewed to extend far beyond the vocal anti-AGW lobby group to the public at large. The research community (you) need to work CLOSELY with the education community NOW to inform a voting public. The only reason John Boehner’s ‘climate change model’ gets traction is because of an uninformed pubic. The truth lies in the data and their interpretation by you. It must be translated rapidly and effectively for public consumption. Folks we’re not fighting back enough. This is a war for the future of the planet and our children. Education is the only hope if we are to change the course of this ship.

    FYI – when it comes to science education for the public at large, standard practice in museums and science centers is to assume the equivalent of 5th grade science literacy if the goal is conceptual understanding.

    I said what I needed to say based on what I read in this thread. You can now throw darts and arrows.

    Here is my humble attempt at an explanation. You can help by helping me tune it.

    A Day in the Life of the Earth: Understanding Human-Induced Climate Change, with forward by Jim Hansen, Dir. of NASA/GISS

    For teachers and parents to educate our children, and to educate the public. The crisis is real. The crisis is now.

    Jeff Goldstein
    Center Director
    National Center for Earth and Space Science Education

    Comment by Jeff goldstein — 12 Aug 2009 @ 1:29 AM

  75. Thomas, that looks like a productive question:

    Comment by Hank Roberts — 12 Aug 2009 @ 1:56 AM

  76. The English lexicon is replete with nouns and adjectives to describe the behaviour John Mashey wishes to define:

    fib, lie, untruth, falsehood, fabrication, fiction, fairy story, tall tale, terminological inexactitude, whopper, …;

    fraudulent, cheating, untrustworthy, false, untruthful, dishonourable, unscrupulous, unprincipled, corrupt, swindling, deceitful, deceiving, deceptive, lying, crafty, cunning, designing, mendacious, double-dealing, underhand, treacherous, perfidious, unfair, unjust, disreputable, rascally, roguish, knavish, crooked, shady, bent, ….

    Grab a few.

    Then, in comparison with words such as “asexual”, one could have “ascientific”.

    Comment by P. Lewis — 12 Aug 2009 @ 5:44 AM

  77. Thank you Oakden Wolf for your work on the links – very useful.

    Comment by Steve Hill — 12 Aug 2009 @ 6:06 AM

  78. In a recent book ‘Ice, Mud and Blood’, the scientist Chris Tunney mentions methane hydrates leaking out from Santa Barbara, California!! (I don’t have the book here with me and hence can’t give you the page number).
    I was under the impression that it will be some time before methane hydrates or clathrates thaw to release methane. Can anyone shed light or informed opinion on this?

    [Response: There are many places on the continental shelf where there is a very dynamic balance between methane gas, hydrates and overlying sediment and water column. At these points (sometimes called seeps) you can find hydrates on the sea floor and in the process of outgassing. Santa Barbara is one such place, and there are recent reports from the Siberian continental shelf showing similar things. These haven’t been studied for very long and so the nature of the dynamics (is this outgassing roughly in balance with methane production? over what time period?) is unclear. Given the depths, water temperature stability, and geologic environment, this isn’t likely to be related to any ongoing climate changes. However, this is not my speciality, and so if anyone could add more details and refs. that would be helpful. – gavin]

    Comment by Nagraj Adve — 12 Aug 2009 @ 7:56 AM

  79. “Come Hell and High Water”, popularly known as the “Business As Usual” scenario.

    An unfortunate choice of words the latter, really. It means for most people that to do nothing differently makes things stay the same as before, so why worry?

    Impact related nomenclature is called for.

    Comment by Pekka Kostamo — 12 Aug 2009 @ 8:03 AM


    This is worth a read on all those pesky climate change questions answered in the equivilent of a IPCC interim report as of Copenhagen this year.

    Comment by pete best — 12 Aug 2009 @ 8:52 AM

  81. With the quite different coninental configuration in the Paleocene surely we would expect both the Charney sensitivity and the Whole Earth Sensitivity to be different fron the current values. But would these sensitivities be higher or lower and by how much? To what extent can this help explain the temperature changes in the PETM?

    Comment by Lloyd Flack — 12 Aug 2009 @ 9:01 AM

  82. Jeff #74 Excellent. Thank you. Thanks to Jim Hansen for his strong stand. Thanks to RealClimate for this beacon of sanity in a crazy world.

    Comment by Hugh Laue — 12 Aug 2009 @ 9:39 AM

  83. #69 – But normal people can read temperature graphs without the need of a lot of statistics. A rule of thumb we used was “the more complicated the analysis, the more suspicious”.

    Comment by J. Bob — 12 Aug 2009 @ 10:02 AM

  84. Jim.

    Agree the wording was OTT on my part but the effect of difficiencies/uncertainties in the climate models can result in a very wide range of outcomes. In my QRA field, to address the uncertainty of future events against historical probabilities of failures, we sometimes apply a factor (usually an order of magnitude) to the final results. The factor depends on the reliability of the historical data. I am not fully versed on the selected “forcing” (thanks LB) factor given to CO2 and how much of a range it has in the various models but is there a method applied to address the uncertainty with this?

    On another note. There are some on this blog who seem angry and intollerant re. some of my posts. I am trying to progress the dialogue, so will not get snotty back at any of you. Peace.

    Comment by Doctor K — 12 Aug 2009 @ 10:18 AM

  85. glen (56), does Lovelock hold that belief because he scientifically thinks it’s inevitable, or because his tack requires less work, as in ‘might as well lie back and enjoy it?’

    Comment by Rod B — 12 Aug 2009 @ 10:30 AM

  86. dhogaza (62), though Doctor K might be defining “substantiated” as having extensive external justification, instead of being strongly supported by the feelings and self-satisfaction of the modelers. (Which. btw, does not mean the modelers shouldn’t run with what they know.)

    Comment by Rod B — 12 Aug 2009 @ 10:42 AM

  87. P.Lewis, wrong words I think. Did you actually read the two press releases linked above and compare them? Read the one from Rice, note the date, Google how its hot button phrases spread; read the one from Moana, note the date, Google for mentions of it. Consider the difference between the two press releases. What did the Rice PR department do?

    Well, where I grew up, it’d be called crapping in their own lunchpail.

    Comment by Hank Roberts — 12 Aug 2009 @ 10:55 AM

  88. “A rule of thumb we used was “the more complicated the analysis, the more suspicious”.

    Comment by J. Bob”

    But the very simple analysis shows CO2 is the major driver. Nothing else manages the change anywhere near that closely. And the denialists trying to make out it’s something else are the ones making weird statistical jumps.

    Yet somehow you feel that these are above reproach…

    Comment by Mark — 12 Aug 2009 @ 10:55 AM

  89. Hey Doctor K, fair enough. You might develop more confidence in our understanding of climate by starting with the basics. By this, I mean don’t worry too much about the big GCMs for now, and instead focus on the underlying thermodynamics. From fairly fundamental radiation physics, we can show that for a large increase in GHG forcing, the atmosphere and oceans must warm, in order to regain radiative equilibrium with space. To my mind, this much is uncontroversial, except to the most partisan.

    The ongoing work of climate science community is to refine our understanding of the how this warming will unfold. This is a much more difficult (and interesting) question. I always recommend Ray’s new book, Principles of Planetary Climate, because it’s a rigorous but accessible treatment, and the online draft is free!

    Comment by Jim Galasyn — 12 Aug 2009 @ 11:17 AM

  90. Doctor K might be defining “substantiated” as having extensive external justification, instead of being strongly supported by the feelings and self-satisfaction of the modelers.

    So do you have any evidence that the only external justification of GCMs is the “feelings and self-satisfaction of the modelers”?

    Or is that just the typical unjustified criticism based on the feelings and self-satisfaction of the denialist community that, for the most part, has never even peeked at the documentation on how, say, GISS Model E works.

    Comment by dhogaza — 12 Aug 2009 @ 11:34 AM

  91. The many interesting twists to the PETM story tells me that we’re not so sure if its missing feedbacks or missing carbon…

    Methane has taken center stage since the composition of carbon in our atmosphere became very light, very fast during the PETM. There is pretty good evidence that this occurred in a single pulse, in less than 500 yrs:

    There is also convincing evidence that the earth was warming a couple thousand years prior to the injection of light carbon (Slujis et al., 2007, Nature).

    Volcanoes were doing interesting things during exactly 55 Mya (breaking up Greenland from Europe and stuff, Storey et al., 2007, Science) and outgassing from the mantle does not change the carbon composition of the atmosphere…

    So what’s so crazy about more carbon and less feedbacks?

    Comment by Adam — 12 Aug 2009 @ 11:58 AM

  92. > more carbon and less feedbacks

    Well, where is the missing carbon?
    Where did it come from, and where did it go?

    Well, maybe carbon might come from geology, say heating of carbonate rocks or coal, if a big magma plume rose up.
    Would that leave any evidence?

    But if it’s excess carbon, to cause the PETM temperature spike, it had to go into the atmosphere, then be removed through biogeochemical cycling at geological speed.

    Where would it go that it’s disappeared — and how might it come back to surprise us, if it’s hidden away somehow?

    Comment by Hank Roberts — 12 Aug 2009 @ 12:17 PM

  93. Oh, wait — where’d this come from?
    Adam, what’s your source for saying this?

    > outgassing from the mantle does not change
    > the carbon composition of the atmosphere

    If you are referring to the isotope ratio that can’t be right.

    Comment by Hank Roberts — 12 Aug 2009 @ 12:25 PM

  94. dhogaza (90), I delibertly and overtly did not say or imply “only.”

    Comment by Rod B — 12 Aug 2009 @ 12:40 PM

  95. (Next try to get past spam filter).
    Thanks to all, so far, for comments on #8; I’m accumulating these suggestions.

    Let me try again, as I obviously didn’t explain it well enough.

    Anti-science seems a good term for {deliberate obfuscation, cherry-picking, purposeful mistitling, and claiming that a paper says something it obviously doesn’t, etc, etc}.


    But, I always recall Napoleon’s:
    “Never ascribe to malice, that which can be explained by incompetence.”

    (And to be fair, “incompetence” may be overly pejorative, as sometimes the real problem is difficult, and it may take strong competence to succeed.)

    While many acts are obviously malice or incompetence, some are less obvious, and it takes a while to discern which is which. Then, if one wants to make real improvements, one can at least try to help raise the level of competence (since malice doesn’t easily get fixed). That was the point of what to do about bad science reporting.

    In another domain, read Wachter & Shojania’s Internal Bleeding – The Truth Behind America’s Terrifying Epidemic of Medical Mistakes. This is a calm discussion by two credible UCSF doctors about systemic errors and possible solutions – hospitals may kill people, but it’s not from malice. Then, I’d guess the publisher insisted on a sensationalist title.


    In #8, I’m concerned, not with malice, but with various forms of incompetence/error, for which I seek a good term, or terms, if different effects need them. Consider the progression from real science to widespread publicity, and the various sources of *noise* that may incrementally distort the original signal:

    1) A researcher may claim (and often even believe) more significance than is justified. Of course, there may well be errors, especially in early papers on a subject, and arguments over significance are part of real science.

    It is always worth recalling the military maxim: “The first report from the front is wrong”, and science by press conference can often make one nervous.

    2) A researcher may perfectly well calibrate their results, but not be very good at communicating to a lay audience, especially when regarding uncertainties. One might call this incompetence, but “lacking this skill” is more like it.

    Even with strong competence, good summarization can be very difficult. It is a nontrivial skill to start with a scientific paper, replete with careful caveats, error-barred charts, tables, backup data, etc, and write a 2-page press release that does it justice. If you find somebody who can do that, take good care of them!

    (As a related example familiar to this audience, it is instructive to read MBH98, MBH99, then follow that topic through TAR WG I full report, TS, and finally SPM, looking especially at error bars (or gray depiction), and considering the likely interpretations by general audiences. Worse were derivative versions in which the gray uncertainty background disappeared entirely, giving a visual impression of exactitude never claimed by the real research. This is a hard problem, as it is a much easier to draw and print/display one simple line, than to show multiple lines and density plots (as per AR4 WG I, p.467). General audiences just don’t think this way. The same effect always arose in computer performance ratings, in which people wanted “one number”, despite experts telling them there was no such thing.

    3) A researcher may not write the press release, and the writer can easily err, quite unconsciously. Assuming the researcher has the time and patience to do good reviews, they may not even realize that the press release fails to convey to the public what they think it does. I.e., *they* know what their research said, and they may not realize that a 1-2-page press release may be ambiguous.

    I spent much time (over decades) wrestling with marketing departments about press releases. If you haven’t done this, you may not realize how much effort is needed to make sure something claims as much as it should, but not too much. In some cases, you just run out of time. People mess up press releases *often*.

    4) Media get press releases, and maybe even interviews the researcher, and then writes stories. Occasionally, one finds malice (I experienced one like that, for a national magazine), but mostly, reporters skills and knowledge follow a normal distribution, from really awful, to terrific, with most being more-or-less average.

    At the very best, a fine reporter does their homework and a good interview , then writes an accurate , clear article. But, even then, *someone else* normally puts the headline on the article, with tight space constraints, and *anything* can happen. (Think of a headline as TwitterScience, but with even less characters).

    5) Media is generally incented to make stories look more important, more exiting, more entertaining, more threatening (as in the book mentioned earlier).

    6) But of course, there may well be anti-science malice tacked on at *any* stage of this process.


    I once did an interview with a fine WSJ reporter, who wrote a good article … and the result was:

    The MIPS Stock Glitch Or How I lost 15% of a Company’s Stock Value in a Few Hours

    This was amusing in retrospect, but not at the time.

    a) I was one of the few techies allowed/encouraged to speak to press and customers, i.e., I was experienced at this, and being a VP, was quotable.

    b) The writer was excellent. He’d studied the paper I wrote that started this, and did a good phone interview.

    c) The article was well-written. I was very impressed by his ability to capture the essence of the issue in a short article. I was ecstatic that it was placed on the top-left corner of the second section, first page.

    d) And it still blew up, badly… because the article headline had an unfortunate ambiguity. I don’t think this was malice on the part of the headline-writer. The headline wasn’t even wrong, just easy to misinterpret.

    e) Compared to explaining complex science, this topic was *trivially easy*.


    If one views this as a signal-transmission issue, maybe the whole thing is science-noise, where some of the noise is natural, and some (anti-science) is purposeful attempt to distort or obscure the signal. Early in the process, it may be hard to tell which is which.

    Comment by John Mashey — 12 Aug 2009 @ 12:55 PM

  96. Jim. High school physics also has a relationship between elevation and temperature PV=RT. Hence, as
    elevation increases, the temperature drops and vica versa. The 33K rise in temperature between elev. 4000m
    and sea level for a column of air can be attributed to that fact of physics under the ideal gas law. If GH gas contribution was doubled, this value would not vary much. How do the models allow for this fact of physics? Has the media done any of their own investigative work on this? How has politics at the UN
    played a role in all of this? From what I can tell, the contribution of CO2 to atmospheric warming is overstated drastically, based on the above. Can anyone here explain this?

    Comment by Doctor K — 12 Aug 2009 @ 1:00 PM

  97. I’m a bit confused. Gavin’s post says (emphasis added):

    The conclusions of the study related to the sensitivity of the climate used the standard range of sensitivities from IPCC TAR (1.5 to 4.5ºC for a doubling of CO2), which have been constrained – not by climate models – but by observed climate changes.

    I thought the range was the convergent outcome of both models (ever since Charney split the difference between Manabe’s and Hansen’s models) and observations?

    [Response: That’s how it started, but the AR4 range (2 to 4.5deg C) is actually based on data-derived constraints. – gavin]

    Comment by CM — 12 Aug 2009 @ 1:31 PM

  98. Re terminology, I like “spin science” (or “sexed-up science”, perhaps?).

    A more specific suggestion for what the press release contained:


    Comment by CM — 12 Aug 2009 @ 1:34 PM

  99. @78[Nagraj Adve & Gavin]:

    Kennet et al. 2000 and E. Solomon et al. 2009 and their refs might be helpful.

    Comment by thingsbreak — 12 Aug 2009 @ 1:48 PM

  100. “From what I can tell, the contribution of CO2 to atmospheric warming is overstated drastically, based on the above. Can anyone here explain this?”


    It’s rather like asking: since the result of the hamiltonian solution to an asymetrically charged nucleus results in quantum imbalances, there seems to be an error in the assumption that atomic fusion will release any energy of use. Can anyone here explain this?

    PV=nRT has nothing to do with CO2 and its only contribution to AGW science is that such an adiabatic lapse rate ensures that the saturated gas argument is incorrect, since such a conclusion only has validity when taken through a homogenous gas, where this lapse rate ensures no such limitation pertains.

    Comment by Mark — 12 Aug 2009 @ 1:52 PM

  101. Doctor K,

    I’m not sure it’s clear what you’re asking. It’s a bit ironic asking how models allow for “fact[s] of physics” seeing as a GCM is – in a terribly simplified way – just a giant physics equation solver. The thermodynamics I think you’re referencing are pretty straightforward (they’re treated in the book that Jim linked for you, and they’re not difficult to understand and derive) and most definitely considered in the core of the model.

    Now, what sort of investigative work do you think the media should do this end? Is it a journalists job to dig through a model’s source code and analyze it? Of course not. Now, we can argue all day about whether or not the media accurately characterizes papers in the scientific press or whether they fairly represent the basic science behind global warming, but it’s not their place to do the actual science. On a similar note, how does UN politics come in to play here? The IPCC merely summarizes the existing literature on the atmosphere and climate change, and then based on projections (informed by presumed, clearly described economic/greenhouse emissions scenarios) makes conservative policy suggestions on how to best avert catastrophic global warming. It’s not like they’re political bosses sitting in the smoke-filled back room of Tammany Hall fabricating scientific figures!

    Finally, I hope you do go back and read through the textbook Jim linked you. That will explain CO2’s role in the atmosphere and global warming far better than a mere comment on a blog can.

    Comment by counters — 12 Aug 2009 @ 1:57 PM

  102. Doctor K, your question about physics and global warming is so ill informed, it is hard to know where to start. Read some basic non-denialist works on GW. In short, no one is saying that warming is from increased pressure of GHGs add to the atmosphere.

    Yes, politics doubtless played a role in IPCC–the findings and especially the recommendations were watered down because of pressure from governments including our own. The decision not to consider the most recent data also ended up creating a report that understated the pace at which the negative effects of global warming would unfold, particularly in the Arctic.

    Why would you think “the contribution of CO2 to atmospheric warming is overstated drastically”? You have to explain your position before anyone can address it intelligently. Since models have turned out to underestimate the amount of warming and other effects, it is more likely that the contribution of CO2 to warming is drastically understated than overstated.

    Comment by wili — 12 Aug 2009 @ 2:00 PM

  103. #88 What simple analysis?

    Comment by J. Bob — 12 Aug 2009 @ 2:03 PM

  104. > what simple analysis

    Comment by Hank Roberts — 12 Aug 2009 @ 2:13 PM

  105. > IPCC …. politics

    “… virtually all of the world’s governments belong to it. Thus, governments that don’t want to do anything about climate change have just as much input to the report as countries that do.

    This tension between the ideological factions of the IPCC actually gives the reports credibility. Only statements that everyone agrees to make it into the report. A few countries that object to some result can keep it out of the report. This is, in fact, why the IPCC process was designed this way.”

    Comment by Hank Roberts — 12 Aug 2009 @ 2:15 PM

  106. Rod B (85)
    glen (56), does Lovelock hold that belief because he scientifically thinks it’s inevitable, or because his tack requires less work, as in ‘might as well lie back and enjoy it?’

    not sure which “belief” you are pointing to?

    Comment by glen — 12 Aug 2009 @ 2:37 PM

  107. #96

    In what sense is the ideal gas law (pV = nRT) a relationship between elevation and temperature? If it were, how can it be that the law holds in both the troposphere and stratosphere, yet air temperature decreases with height in the troposphere (on average), but increases with height in the stratosphere?

    [Response: The ideal gas law is for a circumstance in which there are no phase changes or external energy sources (and for ideal gases of course). So it works well for dry air that is compressed or expanded. In the atmosphere, the pressure is basically just the weight of air above you, and so if you move a dry air parcel up, the pressure will decrease, and the temperature will fall (at about 9 C/km – the dry adiabat). In moist air, you can make a correction assuming that the water vapour will be saturated and the resulting latent heat release when water condenses can be included as a correction to T. This makes the effective cooling rate less (about 6 deg C/km – the moist adiabat). However, if you have significant amounts of radiative transfer (i.e. internal heating from absorption by ozone, water vapour, clouds or aerosols), then the approximations start to break down. So in the stratosphere, where ozone is very important, it doesn’t work at all. It should also be noted that it breaks down as well if there is no convective instability – the atmosphere is perfectly happy to have temperature gradients that are larger than the adiabat (i.e. very cold air near the bottom is stable). – gavin]

    Comment by Jerry Steffens — 12 Aug 2009 @ 2:50 PM

  108. Are we not in a very perilous place already?

    In the paleoclimate record the rate of change was of the order of +0.1K per century, possibly less. And the temporal lag between temperature rise and the observed GHG increase is something in the range between as little as 200 years to maybe 800.

    So the temperature rise that triggered the GHG increase (if it is initiated by temperature rise) is somewhere in the range of 0.2 to 0.8K.

    Which is roughly where we are now, isn’t it?

    Comment by Nigel Williams — 12 Aug 2009 @ 2:52 PM

  109. Re #85 where Rod B questions Lovelock’s motives.

    About 5 years ago, Jame Lovelock visited the Hadley Centre, and discovered that all the scientists were sitting in different rooms in despair at the way the environment, ocean acidification, depletion of fisheries, loss of top soil, desertification , loss of biodiversity, increase in wildfires, melting of glaciers, warming ocean, loss of Arctic sea, and the collapse of the Antarctic Peninsula ice shelves. They could not speak out for fear of being labeled alarmist by the scientists in the other rooms.

    Lovelock wrote his book, “the Revenge of Gaia” to warn about this and proposed nuclear power as the answer to solving the problem of global warming. He believed that when the US came to its senses, they would deal with the problem in their characteristic robust fashion.

    But nothing has happened. He has now written another book:

    The Vanishing Face of Gaia A Final Warning by James Lovelock Allen Lane, London, 2009. 199 pp. £20, C$34. ISBN 9781846141850. Basic Books, New York, 2009. 288 pp. $25. ISBN 9780465015498.

    which Lee Kump reviewed along with a biography of Lovelock by the Gribbens in Science.. It was that article that glen cut and pasted into comment #56.

    I share Lovelock’s despair. The US cannot even sort out the health of their own citizens, far less that of our planet :-(

    Cheers, Alastair.

    Comment by Alastair McDonald — 12 Aug 2009 @ 3:38 PM

  110. #78 Nagraj Adve

    re. Gavins comment and information about methane hydrate clathrates

    Euan Nisbet has been working in that area and last I heard from him the general assessment Gavin made still stands as far as I can tell. It is being looked at and while there are indicators, we don’t know a lot yet. But this is a very interesting area.

    Euan gives a general talk about it. Don’t mind the drop out in the front, it does not last long… and download the slide show to follow along.

    Comment by John P. Reisman (OSS Foundation) — 12 Aug 2009 @ 3:59 PM

  111. Re #109

    I apologise for misspelling John and Mary Gribbin’s surname. I have seen John post here, so I hope he is not offended when he sees my mistake.

    As a further penance I am reposting details of their book [moderators permitting]. Its UK title is He Knew He Was Right: The Irrepressible Life of James Lovelock and Gaia and the US title is James Lovelock In Search of Gaia by John Gribbin and Mary Gribbin Allen Lane, London, 2009. 262 pp. £20, C$42. ISBN 9781846140167. Princeton University Press, Princeton, NJ, 2009. 286 pp. $24.95, £16.95. ISBN 9780691137506.

    Comment by Alastair McDonald — 12 Aug 2009 @ 4:29 PM

  112. glen (106), the following (sorry for the confusion). “…He calls for an immediate shift of focus to adaptation to a hothouse world, expecting that in the coming decades humanity will be forced to migrate to the few habitable refugia that remain (including the British Isles). The world population will be reduced from billions to millions, Gaia selecting those humans with the traits to live sustainably (her revenge)…”

    Comment by Rod B — 12 Aug 2009 @ 5:26 PM

  113. Alastair (109). Interesting. Thanks.

    Comment by Rod B — 12 Aug 2009 @ 5:31 PM

  114. 112 Rod B.

    “…migrate to the few habitable refugia that remain (including the British Isles)”

    That idea has its limitations too, as it will be standing-room only on the British Isles by the time Gaia has settled down again.

    80m sea level rise gives:

    Comment by Nigel Williams — 12 Aug 2009 @ 6:17 PM

  115. Re refugia, I trust we’ve all seen Children of Men? There’s your Lovelockian near-future.

    Comment by Jim Galasyn — 12 Aug 2009 @ 6:38 PM

  116. Re #113

    James Lovelock outlined the ideas from “The Revenge of Gaia” in a lecture to the Royal Society which can be seen here:
    Professor James Lovelock CH CBE FRS “Climate change on the living Earth”

    Comment by Alastair McDonald — 12 Aug 2009 @ 6:40 PM

  117. CM @98


    Ooh! I like it. Ladies and germs, I think we have a winner!

    Dr. K @ 96 Oh dear! You poor man. No wonder you are so confused.

    Comment by Ray Ladbury — 12 Aug 2009 @ 7:17 PM

  118. Gavin,
    You make all the right caveats in your above essay, but the fault lies in how you stress them to your audience. Please indulge me some scientific liberty to make a point.
    Allow us first to surmise that the forcing changes needed to accomplish the PETM temperature spike indeed involve a sustained contribution of CH4 from methane hydrates, as you propose in your 2003 paper. One could imagine that this might hypothetically be triggered by a change of gateways controlling ocean circulation, but it also might be simply be a highly non-linear feedback response to an initially modest CO2 out-gassing from a pulse of volcanic activity. Next, we note that the base climate during the Paleocene was already much warmer than today, and may have already been near a critical threshold that tripped the sustained liberation of methane stored in the gas hydrates. The modern background earth system however may be very far away from such a tipping point so that a modern doubling of C02 triggers much more moderate positive feedbacks. In such a case, the full earth system sensitivity inferred from a doubling of CO2 (after the full geochemical response to the methane release) during the PETM might yield a grossly different sensitivity than for a doubling scenario over the modern background climate. Depending on the location, geometry, and volume of methane hydrates at any given time in the earth system (and we have no idea about the variability of these hydrates over geologic time), there may be no linear scaling of climate sensitivity whatsoever.
    This is just one example of many other potential pitfalls relating a deep time climate to modern analogs. I can think of more factors which might suggest that the earth system response to changing atmospheric gas forcing is non-linear across many different scales, especially across long spans of geologic time.
    Finally, you say in conclusion: “we can all agree that it remains a tantalisingly relevant episode of Earth history.” Relevant to what? If you are subtly inferring that there is any evidence from the PETM that in some way can be used to infer a climate sensitivity of 6-8C to the modern CO2 forcing changes, I’m afraid I will need to call BS on that (as I have done before on this same subject).

    Comment by Bryan S — 12 Aug 2009 @ 7:25 PM

  119. Rod B (112)

    inevitable — Lovelock’s “beliefs” turns everyone on this blog into a climate optimist! He has a pretty gloomy outlook.

    Comment by glen — 12 Aug 2009 @ 9:52 PM

  120. #104 – If it’s so simple, you should be able to explain it, in say 1 or 2 paragraphs, not give a bunch of ref.

    Comment by J. Bob — 12 Aug 2009 @ 10:10 PM

  121. In my first post(56) — what I really wanted to highlight is Lovelock’s reasoning for decrying American Science(maybe I was too subtle). Is American Science emphasizing the wrong science?

    “We seem to have forgotten that science is not wholly based on theory and models: more tiresome and prosaic confirmation by experiment and observation plays just as important a part. Perhaps for social reasons, science has in recent years changed its way of working. Observation in the real world and small-scale experiments on the Earth now take second place to expensive and ever-expanding theoretical models. It may be administratively and politically convenient to work this way, but the consequences could be disastrous. Our tank is near empty of data, and we are running on theoretical vapor: this is especially true of data about the oceans that make up more than 70 percent of the Earth’s surface, and about the responses of ecosystems to climate change — and, just as importantly, the effect of change in the oceans and ecosystems on the climate.
    The ideas that stem from Gaia theory put us in our proper place as part of the Earth system — not the owners, managers, commissars, or people in charge. The Earth has not evolved solely for our benefit, and any changes we make to it are at our own risk. This way of thinking makes dear that we have no special human rights; we are merely one of the partner species in the great enterprise of Gaia. We are creatures of Darwinian evolution, a transient species with a limited lifespan, as were all our numerous distant ancestors. But, unlike almost everything before we emerged on the planet, we are also intelligent, social animals with the possibility of evolving to become a wiser and more intelligent animal, one that might have a greater potential as a partner for the rest of life on Earth. Our goal now is to survive and to live in a way that gives evolution beyond us the best chance. The philosopher John Gray has discussed the extent to which we are still an emerging intelligence and still have far to go to match even our own estimation of ourselves. Do we really believe that we humans, wholly untrained as we are, have the intelligence or capacity to manage the Earth?
    We have become good at burying bad news, and maybe this is why we do not like the reports brought back by those brave and true scientists who go out into the world — like Charles David Keeling and his son Ralph, who for so long and so accurately monitored carbon dioxide on the peak of Mauna Loa, or Andrew Watson who took wintertime measurements from a ship that bounced on the cold and stormy seas off Greenland. There are a few scientists like them who now make observations of temperature and sea-level rise, and their measurements were reported by Stefan Rahmstorf and his colleagues in May 2007 in Science. They found the sea level was rising 1.6 times as fast and the temperature 1.3 times as fast as the IPCC had predicted in 2007. In September 2007 we were devastated to discover that all but 40 percent of the ice floating on the Arctic Ocean had melted. It is true that the visible loss in 2008 was slightly less, but the remaining ice had thinned by a record 1.5 feet. These changes are far more rapid than the gloomiest of model forecasts and, as we shall see, could have serious consequences.
    Through Gaia theory I offer a view of our and the Earth’s possible future as climate change develops. It differs from that of most climate scientists. The differences come from procedure, not from a different factual basis. Most of the climate-change models, for example, do not yet include the physiological response of the ecosystems of the land or oceans. In no way is this the consequence of a battle between theories; it is that climate models stretch our mental and computing capacities so much that it takes a long time before new procedures can be included reliably — it is somewhat like changing the transport system of a city from buses to trams. In an ideal world all-inclusive climate models might lessen or even remove the disagreement, but we cannot afford to wait for perfected models: we have to act now, so I offer predictions based on simple models from Gaia theory and evidence from the Earth now and in the past.
    Professional climatology is based mainly on geophysics and geochemistry and often assumes that the Earth is inert and incapable of a physiological response to climate change. What makes the ideas in this book different is that they are based on a consistent theory of the Earth — Gaia — which has proven itself by successful predictions and is beginning to be accepted as the conventional wisdom of Earth and life science. Do not suppose that conventional wisdom among scientists is similar to consensus among politicians or lawyers. Science is about the truth and should be wholly indifferent to fairness or political expediency.
    When I criticize the IPCC consensus, I am most of all criticizing the lack of wisdom among managers and politicians who forced (I suspect unwilling) scientists to present the conclusions of different national and regional climate centers this way. Just before completing this book, I read Steve Schneider’s deeply moving recent work, A Patient from Hell, about his long and painful but successful battle with cancer. Schneider is one of the world’s leading climate scientists, and he recalls in the book his part in a session at the UN in Geneva during the development of the IPCC Working Group II report of 2001, describing how the good science presented at the session was manipulated until it satisfied all of the national representatives present. The book makes clear that the words used to express the consequences of global heating were blurred until they were acceptable to representatives from the oil-producing nations, who saw their national interests threatened by the scientific truth. If this is what the UN means by consensus, scientific truth cannot be expected to come from its deliberations, and we are misled about the dangers of global heating. This may also be why national governments and international agencies are reluctant to fund observation and measurement but ready to fund models. Measurements by scientists are much harder to contest. It is said that truth is the first casualty of war, and it seems that this is also true of climate change. If I am more right than the consensus, it alters profoundly the best course of individual and political action.”

    Excerpt from J Lovelock’s book The Vanishing Face of Gaia, 2009

    Comment by glen — 12 Aug 2009 @ 10:41 PM

  122. I’m afraid I will need to call BS on that (as I have done before on this same subject).

    Well, yes B[ryan] S, but why do your initials carry any weight whatsover?

    The world wonders.


    This is just one example of many other potential pitfalls relating a deep time climate to modern analogs.

    I’m heartened to see that you reject the “climate has changed drastically over geologic time therefore anthropomorphic change is impossible” crap.

    Thank you.

    I can think of more factors which might suggest that the earth system response to changing atmospheric gas forcing is non-linear across many different scales, especially across long spans of geologic time

    So perhaps the earth isn’t entering an ice age today, after all, as is so widely touted by your denialist cohorts?

    I do presume you’ve informed them of your wisdom, too, and don’t restrict yourself to “correcting” working scientists …

    Comment by dhogaza — 12 Aug 2009 @ 11:16 PM

  123. Doctor K,
    I look forward to the result of your investigations. Personally, the few models I’ve looked at make a point of ‘substantiating’ their asumptions, it’s a key part of building an Earth Systems model. However the fact that they’re assumptions (i.e. parameters) means they are often based on measured values not built from first principles.

    From where I sit it appears that someone that knows nothing about GCMs is claiming GCMs know nothing…not sound foundations for an argument imho.

    Similarly claiming the scientific method will weed out the facts from theories show little understanding as well….it can only weed out theories. And again from my perspective, it seems to be doing a prety good job judging by the lack of substantiated theories telling me there’s nothing to worry about.

    Comment by ross glory — 13 Aug 2009 @ 2:16 AM

  124. Re #109, Joe Romm over at climate progress would not agree with you. He knows the score in the USA with regard to its energy politics and what needs to be done. He also knows that the USA burns 1/4 of the worlds fossil fuels and it needs to start to do something about it. Its wind power is growing nicely but its a slow process that needs a lot of incentives to get going and really make a difference.

    Not relying on middle eastern oil sounds good. Self sufficient in energy provision is another good sound bite and the arguments about the USA new found natural gas reserves can make a big difference in getting rid of coal. Its all up in the air though and as yet not strategy exists.

    Comment by pete best — 13 Aug 2009 @ 3:32 AM

  125. #118 Bryan S (BS)

    dhogaza – you nailed it well.

    Re. BS’s “Relevant to what?” statement:

    Learning more and understanding mechanisms regarding earths climate I imagine.

    And I’m suggesting before you start calling something BS without relevant context you have at least the courage to post your real name… unless of course you are under threat of being fired for calling something BS that you don’t even have context for?

    Nail down the context first, then call BS.

    However, since there is so much yet to learn in this area, I think it is a bit premature to attack what Gavin is saying: “we can all agree that it remains a tantalisingly relevant episode of Earth history.”.

    What I read in Gavin’s inference is that it is a very interesting event and we can learn a lot from it. You’re inferred reading of his inference in my opinion is readily seen as well… BS.

    Comment by John P. Reisman (OSS Foundation) — 13 Aug 2009 @ 3:51 AM

  126. Dr. K,

    PV = nRT only gives lower temperature for a gas due to volume if the gas has expanded. The air at upper altitudes has not expanded; it has been at its present “volume” for a long time. The lapse rate with altitude is due to other factors.

    I recommend checking out a book like Houghton’s “The Physics of Atmospheres” (2002). If you don’t like all the math, an explanation of just this phenomenon (why higher altitudes are colder) is found in an appendix to S. George Philander’s “Is the Temperature Rising?” (1998).

    Comment by Barton Paul Levenson — 13 Aug 2009 @ 5:58 AM

  127. J. Bob writes:

    If it’s so simple, you should be able to explain it, in say 1 or 2 paragraphs, not give a bunch of ref.

    Okay, here it is in two paragraphs.

    The greenhouse effect works like this: sunlight gets through air without much being absorbed, but is absorbed by the ground and heats it. The ground radiates infrared light. Greenhouse gases (GHGs) in the air absorb the IR and this heats the atmosphere. The GHGs in the warmer air radiate infrared, and some of this goes back to the ground, heating it further. You’ve got both sunshine and “atmosphere shine” heating the ground, so a planet with GHGs in its air is warmer than one without.

    Add more GHGs to the air and the ground will get warmer, all else being equal. In the past 150 years, “all else has been equal”–there has been very little variation in sunlight, ENSO, cloud cover, surface albedo, etc., etc. But GHGs have gone way up, and the surface has warmed accordingly. The correlation between NASA GISS temperature anomaly and ln CO2 for 1880-2007 is r = 0.87, which is confirmation of the theory.

    Comment by Barton Paul Levenson — 13 Aug 2009 @ 6:06 AM


    A. Climate change during Cenozoic – the last 65 million years of Earth
    history, i.e. the time after the etxinction of the dinosaurs.

    1. in response to several posts: most paleoceanographers indeed think
    that permanent ice sheets on Antarctica REACHED SEA LEVEL at about
    33.7 Ma (in the earliest Oligocene); e.g. Zachos, J., Pagani, M.,
    Sloan, L., Thomas, E., and Billups, K., 2001, Trends, Rhythms, and
    Aberrations in Global Climate Change 65 Ma to Present. Science, 292:
    686-693. That paper shows development of a significant Arctic ice
    sheet much later, although earlier than 3 Ma ago, i.e. somewhere in
    the late Miocene, about 8-9Ma.
    2. Many scientists would argue that smaller Antarctic ice sheets (and
    present at higher altitudes) developed earlier, with cooling of high
    latitude oceans starting at the end of the early Eocene, i.e. at about
    49 Ma.
    3. Since the publication of Zachos et al 2001 much evidence has been
    published documenting at least possible ice sheet formation on
    Greenland and sea ice in the Arctic somewhere at the same time as on
    Antarctica, i.e., in the middle-late Eocene (45-35 Ma ago). See
    Eldrett, J., Harding, I. C., Wilson, P. A., Butler, E., and Roberts,
    A. P., 2007. Continental ice in Greenland during the Eocene and
    Oligocene. Nature, 446, 176-179, and the special volume of the Journal
    Paleoceanography (vol. 23, 2008; Introduction has doi:
    10.1029/2007PA001516; references in see various references in Thomas,
    E., 2008. Research Focus: Descent into the Icehouse, Geology, 36:
    4. This evidence for global rather than Antarctic cooling reinforces
    the argument that the ice sheet formation at both poles reflects
    falling atmospheric CO2-levels (De Conto, R.M., Pollard, D., 2003:
    Rapid Cenozoic glaciation of Antarctica induced by declining
    atmospheric CO2. Nature, 42,: 245-249; Liu, Z., Pagani, M., Zinniker,
    D., DeConto, R., Huber, M., Brinkhuis, H., Shah, S. R., Lackie, M. R.,
    and Pearson, A., 2009. Global Cooling during the Eocene-Oligocene
    Transition. Science 323, 1187-1190)
    4. There is indeed ample evidence for warm (even very warm Arctic)
    during the PETM; see e.g. Pagani et al., 2006, Arctic hydrology during
    global warming at the Palaeocene/Eocene thermal maximum, Nature 442,
    671-675, and references therein; many papers in the special volume of
    the Journal Paleoceanography mentioned above (vol. 23, 2008;
    Introduction has doi:10.1029/2007PA001516)
    5. Antarctica as a separate continent formed during the split-up of
    the southern continent of Gondwanaland during the Early Cretaceous, so
    any Antarctic climates during the Triassic (much earlier than the
    Cretaceous) can not really be used to arguments on the most recent
    Antarctic ice sheet.
    5. Yes, such a warm world would have a very different ocean, biosphere
    and climate system than what we know today – see for reviews e.g.
    Thomas E., Brinkhuis, H., Huber, M., and Röhl, U., 2006. An ocean view
    of the early Cenozoic Greenhouse World. Oceanography (Special Volume
    on Ocean Drilling), 19: 63-72 or Huber, M., and Thomas, E., 2008.
    Paleoceanography: Greenhouse Climates. Encyclopedia of Ocean Sciences,
    J. H. Steele, S. A. Thorpe and K. K. Turekian, eds. , 2nd edition,
    (Elsevier), p. 4229-4239; doi: 10.1016/B978-012374473-9.00701.3; and
    references therein.

    B. Extinctions during the PETM: in fact, there was NOT a lot of
    extinction during the PETM, even if I have in many instances argued
    for serious extinction. Robert Kunzig said in Discover magazine in
    March 2004: ‘Not much that “WE” care about died then; the most
    prominent victims were deep-ocean microscopic foraminifera that live
    on the sea floor’. Since I have been studying these microscopic
    organisms for many years I do not think that I am included in the ‘we’
    above. However, oceanic surface dwellers did show evolutionary
    turnover and changes in their assemblages but no great extinctions;
    many organisms on land and in the sea show exactly what we expect
    during global warming, i.e. migration from low to higher latitudes.
    Mammals show high rates of evolution, not so much of extinction (see
    review by Gingerich, P. D., 2006, Environment and Evolution through
    the Paleocene-Eocene Thermal Maximum; Trends in Ecology and Evolution,
    21 (5). In my opinion we can still not explain the extinction of deep-
    sea bottom dwelling foraminifera; they live in the largest habitat on
    Earth, and many species are cosmopolitan, so than can easily re-
    migrate in if they go extinct locally. We have no evidence that all
    the world deep oceans became anoxic or highly corrosive to carbonate.
    They did not suffer significant extinction during the mass extinction
    at the end of the Cretaceous. Animals (i.e., metazoan organisms) in
    the same environment did not go extinct to such a large degree (paper
    in press, September volume of the journal Geology, Webb, A. E.,
    Leighton, L. R., Schellenberg, S. A., Landau, E. A., and Thomas, E.,
    2009, in press. Impact of Paleocene-Eocene global warming on
    microbenthic community structure: using rank-abundance curves to
    quantify ecological response. They have short lifespans months to a
    few years at the maximum). So I do think it is important to undertsand
    what happened to them at the PETM: was it the warmth itself and
    changes in metabolic rates and effects on ecosystems? was it
    sensitivity to environmental pCO2 in the oceans, which supposedly is
    higher for unicellular organisms than for animals (e.g., Melzner et
    al., 2009, Physiological basis for high CO2 tolerance in marine
    ectothermic animals: pre-adaptation through lifestyle and ontogeny?
    Biogeosciences Discuss. 6, 4693-4738)?

    Reviews of biotic reactions to the PETM are: Bowen, G. J., Bralower,
    T. J., Dickens, G. R., Delaney, M., Kelly, D. C., Koch, P. L., Kump,
    L. R., Meng, J., Sloan, L. C., Thomas, E., Wing, S. L., Zachos, J. C.,
    2006. Disciplinary and cross-disciplinary study of the Paleocene-
    Eocene Thermal Maximum gives new insight into greenhouse gas-induced
    environmental and biotic change. EOS Transactions AGU, v. 87 (17), p.
    165, 169, and Sluijs, A., Bowen, G. J., Brinkhuis, H., Lourens, L. J.,
    and Thomas, E., 2007. The Palaeocene-Eocene Thermal maximum super
    greenhouse: biotic and geochemical signatures, age models and
    mechanisms of climate change. ‘Deep Time Perspectives on Climate
    Change: Marrying the Signal from Computer Models and Biological
    Proxies’, eds. M. Williams, A. M. Haywood, F. J. Gregory, and D. N.
    Schmidt, The Micropalaeontological Society, Special Publications, The
    Geological Society, London, 323-351

    Comment by Ellen Thomas — 13 Aug 2009 @ 7:11 AM

  129. Re #128, If we have evidence of ice sheets on Greenland and Antartica as far back as 49 mya then does that mean that we will not threaten them until we reach much higher levels of GHG than we might be thinking now. Those foraminifera appear to be the method that is used to reconstruct past ocean temperatures and indeed indicate when they started to form.

    If summer Arctic sea ice is disappearing but Greenland and WAIS are safe for now although they are losing mass then at what point did the great ice sheets stabalise I wonder in terms of mass balance?

    Comment by pete best — 13 Aug 2009 @ 9:26 AM

  130. Dr. Thomas, thank you.
    > what happened to them at the PETM
    Your post helps make the puzzle easier to appreciate

    All — That’s a wonderful compilation. Paste those cites given as text directly into Google Scholar, to get links to papers or abstracts.

    Comment by Hank Roberts — 13 Aug 2009 @ 10:01 AM

  131. #127 Barton, I assume you are using the “homogenized”, or “corrected” temperatures, that seems to change, or “re-homogenized” over time. Have you looked at other sources, closer to the original data, to correlate against CO2? Try correlating CO2 against the 1659-2008 English data or go to:

    and look for long term temperatures without being “homogenized”. Here’s a hint:
    Stockholm-GML 1755-2005
    Stuttgart Ger 1792-2005

    At least the English and Stuttgart data, being in the heart of the early industrial revolution, would show some influence on AGW. The oldest US data
    Mpls-St. Paul USA 1819-2006
    Is fairly flat except for a dip in the 1880’s.

    Use the Rimfrost option to sort on length of data to get the oldest sets of the original data (wo GISS homogenization). It’s not the best, but gives a idea where some of the oldest data is.

    When you start using more of the long term, 150+ years, more original data, then we can talk. Establishing significant correlation C02 and “global temperature” is NOT a simple statistics exercise.

    P.S. Having had graduate & post grad work in radiation heat transfer, as well as working in that area, I’m well aware of the Far to Near IR region of the atmosphere.

    Comment by J. Bob — 13 Aug 2009 @ 11:23 AM

  132. Pete Best, you’re asking questions based on assumptions Greenland quit melting? What basis do you have for this belief? Where are you reading it? The IPY news is pretty well covered:

    Comment by Hank Roberts — 13 Aug 2009 @ 12:39 PM

  133. JBob’s having a laff isn’t he?
    First says he can’t be troubled to read even the Start Here link for the basics, then a day later asserts he has gone past a graduate degree in, and now has a job involving, radiation physics.

    Claim authority based on a graduate degree?
    Say where and when obtained and who you are.
    Else nobody can verify that you’re not a dog …

    Comment by Hank Roberts — 13 Aug 2009 @ 12:45 PM

  134. Re: post 93

    >Oh, wait — where’d this come from?
    >Adam, what’s your source for saying this?

    >>outgassing from the mantle does not change
    >>the carbon composition of the atmosphere

    Delta-13 C of atmosphere over geologic time (+2 to -7 per mil) is near mantle carbon values(0 to -10 per mil)…Which makes sense since that’s where our atmosphere came from! Massive degassing of primordial carbon would be nearly invisible to the Delta-13 C of our atmosphere. Check any isotope book or carbon cycle paper.

    >Well, where is the missing carbon?
    >Where did it come from, and where did it go?

    The relationship between flood basalts and catastrophe is undeniable (e.g., Siberian Traps, CAMP Volcanism and for the PETM, North Atlantic Igenous Province). The paper we are discussing in this post suggests that methane release may not explain the extreme warming or ~2km rise in CCD. Therefore, missing carbon, not missing feedbacks, can explain this discprepency…see post 92

    Comment by Adam — 13 Aug 2009 @ 12:57 PM

  135. PS for Pete, did you read to the end of the Newsweek piece?
    It’s being quoted quite a bit. Google as of today:

    Results … about 428 for “A consensus has developed during IPY that the Greenland ice sheet will disappear”

    Comment by Hank Roberts — 13 Aug 2009 @ 1:19 PM

  136. Adam, what would have happened to the carbon you’re talking about? Is there a spike in accumulation of some carbon-containing material (sedimentary rock, presumably?) associated with the end of the PETM? I haven’t found mention of such, and as I read the original post, that’s part of the puzzle — if there were such a spike in carbon what became of it, how did it leave the atmosphere, where did it move to?

    Comment by Hank Roberts — 13 Aug 2009 @ 1:25 PM

  137. Re: Two paragraphs… I wrote the following textual passage to explain and discuss measured data supporting global heating by GHGs to friends who may not be knowledgeable or patient enough to understand more complicated descriptions. The passage reads better broken into smaller paragraphs, but it still is fairly short. If anyone could suggest some editing to improve it, thanks in advance.

    Lets discuss the key data supporting global warming… the effect can be summarized fairly briefly:

    First look at the heat balance on Earth:
    1. Energy from the sun strikes the Earth, and some of the energy is absorbed in the atmosphere and at the surface.
    2. The only way that energy can leave the Earth is as long wave radiation (similar to the infrared radiation a human emits, that can be seen in IR detectors, such as those used by the military). This is because the Earth is surrounded by the vacuum of space, which prevents heat loss except by LW radiation.
    3. LW radiation increases as the temperature of the upper troposphere increases, and decreases as the temperature drops. LW radiation from lower levels of the atmosphere are mostly absorbed, then re-radiated. In the upper troposphere, and in the even higher stratosphere, most of the outward LW radiation escapes into space.
    4. If the energy coming in from the sun is higher than the LW radiation emitted outward, the Earth gets hotter. And the heat must build up somewhere. The bulk of the excess heat will end up in the oceans, with lesser amounts melting icecaps and glaciers, and even lesser amounts heating up the air and water vapor in the atmosphere, thus raising global temperatures.

    Now lets look at the data; satellite measurements show that the temperatures of the upper troposphere and stratosphere are cooling globally, so the net LW radiation going out is dropping. This is incontrovertible… a lower temperature in the atmosphere at that level must result in less outgoing LW radiation and hence less heat loss.

    So where is the heat building up? In the oceans! Sea levels have been steadily rising, and although a portion of sea level increase is due to the melting of ice sheets, the bulk is due to thermal expansion of sea water. This is also incontrovertible… rising sea levels clearly show increased heating of our planet.

    In addition, NASA’s GRACE satellite project (which uses changes in measured gravitational pull) clearly show that the ice sheets in Greenland and Antarctic are losing ice mass. Furthermore,the long term global temperature record for the planet surface shows that the ten hottest years have been in the period from 1998 until 2008. So all three major components of our planet are showing heat buildup; the lower atmosphere and surface is heating, the ice sheets are absorbing more heat, and most importantly, the oceans are heating.

    Meanwhile, other possible sources of heat, such as total solar irradiance (TSI) remain remarkably constant. Although there is an eleven year cycle in TSI, the net energy from changes in solar are almost insignificant in explaining the heat buldup on Earth. A major volcanic eruption can slow down the heating for several years, but the planet has heated over time in spite of the cooling effect of these eruptions.

    Notice, all this data clearly shows global heating. These key datasets showing global warming are actual measured data, and don’t rely on the complex computer models attempting to analyze the impacts of increased GHGs on the planet. The facts point overwhelmingly to global warming, and the heat buildup will impact and severely change our planet’s existing biosphere.

    Comment by Paul K in Seattle — 13 Aug 2009 @ 1:32 PM

  138. One for Gavin —

    noticing “Earth Systems” turn up here
    via a link I followed from the International Polar Year page; does what they’re doing have any relation to the Earth System Sensitivity term you talked about in the original post?

    The page includes links for

    “Earth system research online consultation … deadline … extended to 1 September.”
    “World Climate Conference-3 (WCC-3) … in Geneva, Switzerland, 31 August – 4 September. WCC-3, co-sponsored by ICSU, will identify the essential elements of a global framework for meeting the future climate information needs of the United Nations …”

    Comment by Hank Roberts — 13 Aug 2009 @ 1:55 PM

  139. Adam, I’m working on this but not clear why a large volcanic CO2 spike wouldn’t show up. Is this the sort of discussion and analysis you’re talking about when you say there’s no difference expected?
    Interpreting carbon-isotope excursions: carbonates and organic matter
    Lee R. Kump* and Michael A. Arthur

    “… . The counterintuitive overall result of the enhanced organic carbon burial event is that the carbonate carbon isotopic composition actually decreases because of the more substantial increase in δ13Corg. In addition, we illustrate the effects on carbon isotopic compositions of the oceanic inorganic carbon reservoir and buried organic matter of a 50% increase in volcanic CO2 outgassing ….”

    Cited By in Scopus (164)

    Comment by Hank Roberts — 13 Aug 2009 @ 2:28 PM

  140. #133 Hank – If it’s so easy, how about your 1-2 paragraph proof of CO2 warming? One shouldn’t need a link to more links.

    Comment by J. Bob — 13 Aug 2009 @ 2:29 PM

  141. You’re now chasing your own imagination, J.Bob, and deluding yourself I offered you the impossible you dream of.

    Mathematics has proofs.

    “For the physics with equations there is no shortcut: you must study the full, complex story as described in textbooks for science students.”

    Anyone who claims a graduate degree and a job in radiation physics but still imagines a 2-page proof in words is badly wrong about something. Try to track your the error.

    Comment by Hank Roberts — 13 Aug 2009 @ 5:13 PM

  142. Oh, and the updated version:

    “… it would do little good to present a copy of the Manabe-Wetherald paper to a technically trained person who demands proof that global warming is a problem. The paper gives only a sketch of complex and lengthy computations that take place, so to speak, offstage….”

    “I’m not saying we don’t understand the greenhouse effect. We understand the basic physics just fine, and can explain it in a minute to a curious non-scientist. (Like this: greenhouse gases let sunlight through to the Earth’s surface, which gets warm; the surface sends infrared radiation back up, which is absorbed by the gases at various levels and warms up the air; the air radiates some of this energy back to the surface, keeping it warmer than it would be without the gases.) For a scientist, you can give a technical explanation in a few paragraphs. But if you want to get reliable numbers—if you want to know whether raising the level of greenhouse gases will bring a trivial warming or a catastrophe—you have to figure in humidity, convection, aerosol pollution, and a pile of other features of the climate system, all fitted together in lengthy computer runs.”

    Comment by Hank Roberts — 13 Aug 2009 @ 5:27 PM

  143. No clue what to call this bizarre saga of science and media — it’s a first for me.

    Gavin and I have had a few emails over the last few weeks, and he kindly told me ahead of time about the idea of posting a “PETM weirdness” article on RealClimate. Of course, we have had a few interesting back and forth discussions. So, with Gavin’s blessing, I post parts of these (with some editorial modifications).

    Well, first off, there was no deliberate attempt on my part to hype the story. A press guy at Rice contacted me about the paper (after seeing a release by Nature). After about 45 minutes of chatting and all, he asked me for a basic summary of why the paper is interesting, whereby I gave the quote: *In a nutshell, there appears to be something fundamentally wrong with the way temperature and carbon are linked in climate models.* Okay, think here — I’m an oceanographer not a politician nor a movie star — I had no idea that the story and the quote would take off through the media like a rocket. So, yes, in retrospect, I agree the quote might have been cut, reworded, stressed differently, etc., given its over-saturation and public consumption. (Though please note the crucial word *appears*, and thankfully this came through in most references to the quote). I disagree with Gavin, though, that the title of the paper should be worded differently – this hits right at the main message (more below).

    There have been two diametrically opposed responses, which I find fascinating.

    One response, with hindsight, was fairly obvious. Skeptics of global climate took the quote as true but completely out of context. This led to suggestions that climate models are intrinsically wrong, that future global warming is unlikely, and other such commentary. This response is probably not worth dwelling upon at RealClimate; as pointed out by the Washington Post and several blogs above, neither the original article nor the press release lead to such inferences. In fact, as correctly noted by the Washington Post, one might take from the original paper or the press release that, if anything, climate sensitivity as often modeled is too low for a given carbon input.

    The other response was somewhat surprising. Several of my colleagues from the climate modeling community reacted as if the statement was entirely false (i.e., Jerry – how could you possibly have said that ….)

    For a truly meaningful discussion, we probably need to qualify the quote with some definitions, in particular like what does *fundamentally wrong* mean. (This is where, I think, Gavin and I both agree and disagree). In any case, and to bypass the semantics for now, to date:

    1/ No climate model has been able to explain temperature distributions, especially at
    high-latitudes, during past *Greenhouse intervals* (e.g., the early Paleogene – nominally 60 to 48 million years ago). We can argue ad infinitum about the merits and demerits of individual proxies for past temperature, but the sum total of evidence for extreme high latitude warmth during past time intervals is overwhelming and unexplained. My favorite example, because it’s across the street where I can show kindergarten kids, is the beautiful early Eocene fossil palm frond from Wyoming at the Houston Museum of Natural Science. Does a current model exist which can explain early Paleogene temperatures – well maybe – but this has not been demonstrated.

    2/ No sophisticated model has been able to adequately explain changes in late Quaternary climate (or other intervals) with CO2 as an internal parameter (i.e., as a coupled feedback that responds to external forcing). Instead, CO2 (and usually methane) are prescribed as external parameters.

    3/ Our interpretations for the PETM (aka the Nature Geoscience article), assuming they are correct, suggest another problem. This is one regarding sensitivity to carbon input. Specifically, that the sensitivity is too low.

    [Here, it is worth responding to Gavin’s blog on two issues. If CO2 was much lower than 1000 ppmv in the early Paleogene (which is inconsistent with most proxy data, especially and interestingly the presence of the mineral nacohlite in lake deposits), then the temperature discrepancies between models and data pointed (item 1) are worse than suggested. If elevated atmospheric methane is the correct answer for enhanced sensitivity (which is inconsistent with the extended >30,000 yr of warmth following the carbon injection at the start of the PETM), where is this source or feedback of methane in climate models?]

    These are, in my opinion as a scientist, pretty fundamental problems with current climate models. Does this mean that the models are wrong or that the idea of AGW is incorrect – absolutely not. But, the *paleo-evidence* definitely suggests that some component linking atmospheric carbon and global temperature is missing, at least on the 1000 year time-scale. I (and other colleagues) strongly suspect there is a major positive feedback involving methane, the terrestrial biosphere, or both. Does the unknown *it* need to be included the short term predictions for global climate … well that’s an interesting question indeed!

    I guess the one bright side to the PETM weirdness saga is that probably thousands of new people now know about this truly amazing event in Earth’s history. Ellen’s references are great ones for reading. If anyone is really interested, I also attempted to write a short article for the public earlier this year at:


    Comment by Jerry Dickens — 13 Aug 2009 @ 5:36 PM

  144. #137 Paul, there has been a gradual rise (trend line) in temperature, according to the East English data, since 1659. So how is that related to man or CO2? The earth has probably been warming since the last glacial period. Again, looking at long term temperatures (~200 years, what correlation to C02 can you show?

    Comment by J. Bob — 13 Aug 2009 @ 5:52 PM

  145. Re post 92,93,139…


    Perhaps I shouldn’t have suggested any ‘carbon cycle paper’…In the paper you cite, he actually relates global temperature to photosynthetic fractionation, which is interesting, but confuses my point that volcanic degassing would go unnoticed in the atmos. delta-13 C. Kump often uses functions relating global temperature to something, for example,increased organic matter burial. Burial of very light carbon (delta-13 C -25 per mil), would cause the atmos. delta-13 C to be strongly positive. Therefore, you can see how a Kump model of volcanic degassing of CO2 (again, delta-13 C of ~-5 per mil) would have purely indirect effects on delta-13 C of atmos.

    If you look closely in the paper you cite, it should say that volcanic CO2 is ~-5 per mil. In Payne and Kump, 2007,

    “To investigate the potential effects of these eruptions, we modeled the
    release of 3×1018 mol of volcanogenic CO2 (δ13C=−5%) over periods of 100, 300, and 600 ky.”

    Now, volcanic degassing would have gone unnoticed to atmos. delta-13 C, but wouldn’t have gone unnoticed to the CCD…which rose more than can be explained by estimates of methane release during PETM…hence, volcanoes.

    Comment by Adam — 13 Aug 2009 @ 6:29 PM

  146. > probably been warming since the last glacial

    Way, way off topic. I sure wish you guys who want to prevent the discussion of the PETM would get a blog somewhere else. But as long as you’re here:

    Says who? Why do you think so? Got a source? Got any logic or facts?

    It’s sort of true, not quite the way you spin it.

    And that’s odd, because the normal pattern is that the planet would have been cooling — as it did after each previous interglacial peak. You can look it up.

    For any youngster who needs the help, here it is.
    Note today is at the left side of the timeline:

    This last interglacial peak was different — the cooling barely began and then — agriculture and the human activity began, this last time around.

    Comment by Hank Roberts — 13 Aug 2009 @ 6:40 PM

  147. Closer to back on topic:

    Comment by Hank Roberts — 13 Aug 2009 @ 6:43 PM

  148. Jerry Dickens, thanks for posting.

    I have to wonder, though, how can models be “fundamentally wrong” if, as you say here:

    Does this mean that the models are wrong or that the idea of AGW is incorrect – absolutely not.

    They’re not wrong?

    I think “fundamental problems”, which you also say, is a better phrasing, though still subject to deliberate misrepresentation (lies) from denialists.

    But even better would be to state that the models “are imperfect”, or something else milder.

    Because the denialsphere can be *guaranteed* to pick up on the word “fundamental”, and then to scream repeatedly that you’re saying “CO2 does not cause warming”.

    It’s a shame that as a scientist you have to be the least bit concerned about political operatives intentionally lying about your work by quote mining or otherwise misrepresenting things you’ve said in all innocence and honesty.

    But, I’m sorry, you’ve got to worry about it. These people can be relied upon to ignore what a paper actually concludes and to twist your words to say the opposite if you give them the least opportunity.

    You’ve got to be on your toes, I’m afraid, and actively guard against dishonest misrepresentations of your work and words if you want to avoid a repeat experience.

    Comment by dhogaza — 13 Aug 2009 @ 6:47 PM

  149. Dr. Dickens’s post slipped in as I was writing.
    THANK YOU, and thank you for commenting on Dr. Thomas’s references and adding your article, and — please — more from you all who are actually doing the science.

    Dr. Thomas gave us one such – the personal really helps:

    “the most prominent victims were deep-ocean microscopic foraminifera that live on the sea floor’ …. I have been studying these microscopic organisms for many years …”

    How does an event like this do the most harm to the best protected organisms? Something odd fell through the depth of the ocean and landed on them?? (grin) Maybe a toxic bloom… argh. I’ll quit speculating. But … more please.

    Mention the obvious that interests you. What was alive on Earth where (or, where should we ordinary readers look to all get on the same page about what we should know to be able to follow your conversations).

    Comment by Hank Roberts — 13 Aug 2009 @ 7:09 PM

  150. Re: #144 (J. Bob)

    Your characterization of central England temperature is both wrong and misleading.

    Comment by tamino — 13 Aug 2009 @ 7:18 PM

  151. J. Bob (144) — Well, no. The Holocene Optimum was many thousands of years ago and since then the global has, on average, been slowly cooling until around 1850 CE.

    Comment by David B. Benson — 13 Aug 2009 @ 7:46 PM

  152. @140 “Bob” If it’s so easy, how about your 1-2 paragraph proof of CO2 warming?

    Prior to Keeling, the concentration of carbon dioxide in the atmosphere was thought to be affected by constant variability. Keeling had perfected the measurement techniques and observed strong diurnal behaviour with steady values of about 310 ppm in the afternoon at three locations (Big Sur near Monterey, the rain forests of Olympic Peninsula and high mountain forests in Arizona). By measuring the ratio of two isotopes of carbon, Keeling attributed the diurnal change to respiration from local plants and soils, with afternoon values representative of the “free atmosphere”. By 1960, Keeling and his group established the measurement record that was long enough to see not just the diurnal and seasonal variations, but also a year-on-year increase that roughly matched the amount of fossil fuels burned per year.

    Comment by savegaia — 13 Aug 2009 @ 8:32 PM

  153. Jerry Dickens:

    Thanks for posting, and welcome to the weird world of talking to the press, as amplified by the blogosphere these days, something we didn’t ahve to worry about 20 years ago.

    If you haven’t read all this, you might try malice vs incompetence, here. Your experience could have been worse.

    Also, (for anyone), I recommend Richard Hayes, Daniel Grossman, A Scientist’s Guide to Talking with the Media – Practical Advice from the Union of Concerned Scientists, 2006.

    Comment by John Mashey — 13 Aug 2009 @ 10:10 PM

  154. Dr. Dickens,

    You made the comment:

    “No sophisticated model has been able to adequately explain changes in late Quaternary climate (or other intervals) with CO2 as an internal parameter (i.e., as a coupled feedback that responds to external forcing). Instead, CO2 (and usually methane) are prescribed as external parameters.”

    Your statement gets at the heart of an important issue. The coupled models that are being used for these types of deep time geological process experiments are essentially weather prediction models with some modifications, and are being employed to try and solve problems that they were not designed to solve. Why should we expect them to faithfully reproduce many of the important non-linear emergent properties within the earth system, when many of the important geological, biological, and biogeochemical processes are absent from their code? If one wants to attempt to test certain physical hypotheses of the short-term effect of changes in atmospheric composition on weather and climate (modern climate prediction problems), that is fine, but it is unfair to expect more than the current generation of models are coded to deliver. Numerical models would essentially need to accurately depict the geological and biological evolution of the entire earth system with all its feedbacks between its various components, to even have a chance to produce many of the complex phenomena we observe in deep time climate. Can you imagine a dynamic model that numerically simulates the ES of the entire Cenozoic, where process such as crustal deformation, basin subsidence and deposition, dynamic fluid flow through the rocks, hydrocarbon generation, methane hydrate formation, benthic and pelagic ecology, and all other sorts of goodies were realistically depicted by a numerical model? Interestingly, Gavin seems to be urging usage of the “Earth System” approach, and I think may be hinting that he favors the ambitious goal to build such an integrated earth system model. (I hope he will comment in this.) In any case, I think your view of the role of numerical models is in error. They are simply tools that allow certain well-defined hypotheses to be tested numerically. They are not all-inclusive earth system prediction tools.

    Comment by Bryan S — 13 Aug 2009 @ 10:38 PM

  155. Hello,

    In response to some posts and emails … and to emphasize precise wording … the quote that initiated all this “weirdness” was *In a nutshell, there appears to be something fundamentally wrong with the way temperature and carbon are linked in climate models.*

    This should not be equated with *climate models are fundamentally wrong* — it’s the coupling of temperature and carbon that appears to be wrong when we examine intervals of Earth’s past — presumably because an important component of the climate system is either missing or incorrectly parameterized in existing models.

    Is this crucial for understanding climate change over the next 100 years? Can the discrepancies be solved with a (future) sophisticated model that has carbon fluxes as internal responses to the system (plus/minus other potentially interesting feedbacks such as peat oxidation and hurricanes)? These are great questions.

    (And hopefully this does not get taken out of context … again!)


    Comment by Jerry Dickens — 13 Aug 2009 @ 10:43 PM

  156. Could the large and rapid (relatively speaking) rise in GHGs have been initiated by a meteor strike? The idea being that the meteor strike, occurs in a geographically sensitive area (say, continental margins, deep seas, etc) and destabilises deposits of methane hydrates. That could get the ball rolling, so to speak. Presumably there would be geological evidence of the isotopic variety, if meteor strike(s) occurred before or during the PETM.



    Comment by Donald Oats — 14 Aug 2009 @ 12:43 AM

  157. Hat tip to Robert Grumbine, here:
    Excerpt therefrom:

    “… the volcanic source of CO2 is depleted in 14C, but not in 13C. The source of the CO2 rise is fully depleted in 14C, but is also depleted (some, a large amount as these things go) in 13C … i.e., it is very (greater than 50 ky) old carbon from a biological source (fossil fuels, carbonate rocks).

    Jan Schloerer wrote up, more than a decade ago, the CO2 Rise FAQ. Jan also managed to write a faq on the topic that is readable by nonprofessionals.

    While much work has been done in the last 10-15 years, it does not change the basic picture he documented back then (follow up his citations to the professional literature). The basics of this case were established in the late 1950s and early 1960s. Keeling’s first papers on observing CO2 included the isotopic composition for just this reason.”
    — end excerpt —

    Comment by Hank Roberts — 14 Aug 2009 @ 1:10 AM

  158. Re 132 and 135

    Pine Island Glacier is thinning 4x faster than it was a decade ago. To some degree this might answer my question on the formation of the worlds three main ice sheets (WAIS,EAIS and Greenland) and when they formed and how stable they are. Its looking worrying for to go from 600 year melt rate to 100 is alarming some might suggest but with the warming in the pipeline to come it might disappear in even less time then it presently is.

    The world has never experienced warming at this rate, its unprecedented in the history of the earth for 200 years is not even a geological time.

    Comment by pete best — 14 Aug 2009 @ 4:27 AM

  159. J. Bob writes

    When you start using more of the long term, 150+ years, more original data, then we can talk. Establishing significant correlation C02 and “global temperature” is NOT a simple statistics exercise.

    P.S. Having had graduate & post grad work in radiation heat transfer, as well as working in that area, I’m well aware of the Far to Near IR region of the atmosphere.

    A response like this tells me you’re going to ignore anything anyone says that might threaten your fixed views on this subject. You asked me to explain AGW in two paragraphs; I did it, you reject it. And why? Because you’ve bought into the denier “the NASA data is tampered with!” line. Gimme a break. FYI, I get major contributions from CO2 with Hadley CRU and UAH TLT data as well. And global data is more relevant than data from central England, or even from Scandinavia. As a statistics minor, I know that much.

    Comment by Barton Paul Levenson — 14 Aug 2009 @ 4:50 AM

  160. #143 Jerry Dickens

    Jonas Salk once told me he solved the polio virus by imagining he was the virus, and what in the human body might hurt him. Einstein and many if not most scientists play in the same way with though experiments. The question of mechanism in PETM and Eocene optimum remains interesting and is an important key to building better models to get us closer to modeling the events more accurately.

    I have had success presenting the contexts of ‘models are always wrong’ so I can relate to your expression. Unfortunately, I also know how such things get spun out of context.

    combined with a rather intense 35 minute presentation and I add the following arguments in my slide show:

    I believe we are still underestimating the potentials and rapidity of change, as well as the economic consequences.

    My guess is that the combined effects of multiple feedbacks in the past amplified the total effect through the resonance of one feedback upon another. Almost like a fundamental frequency in a structure amplifying upon itself, once disturbed, at the right frequency (see galloping gertie)

    The amplification waves are resonating on a slower time scale than physical vibration but the effect is likely the same.

    This would occur until a peak equilibrium is reached, or a system break/state change and then natural processes might mitigate/ameliorate the peak forcing over time with the main mechanism being Milankovitch cycles combining with earth processes.

    Of course I don’t have a clue what these mechanisms are? Sort of like looking at and result and saying: wow, something caused that, but I can’t see the cause. But I would love to sit in on a discussion from this perspective just to see what pops up.

    There is an indication of a temporal high end state (or max ceiling), based on planetary and atmospheric configuration. The questions seem to be what are the component mechanisms, and what happens around the high end thermal equilibrium? Maybe imagining this from that perspective might yield new insights from which one might work backwards towards our current state and discover new mechanisms to model?

    Comment by John P. Reisman (OSS Foundation) — 14 Aug 2009 @ 7:15 AM

  161. Thanks to Ellen Thomas (#128) and Jerry Dickens (#143). In my quick scan I didn’t catch the link to ‘earth system sensitivity’ and would like to read more.

    One of the important points in all these discussions is the concept of feedback. To an atmospheric scientist, changes in earth surface conditions are not considered as feedbacks, because they change what are typically considered the boundary conditions.

    Slow changes to the system should really be described by a different term, like climate memory or inertia.

    The fundamental point of the PETM study is that the slow changes tend to amplify the change beyond the temperature one would expect from merely a change in capture of longwave radiation.

    Comment by Mitch Lyle — 14 Aug 2009 @ 7:30 AM

  162. hmmm, this idea makes me think… upon reflection, maybe this should be looked at exactly like a physical vibration since it actually is a brand of vibration on the molecular level resonating on the climate system in years, decades per cycle based on energy increases in the forcing levels contained within the sphere of earth atmosphere, a wonderful place to resonate effects inside a concave GHG shell. We need to slice up the components and look at how they resonate inside the shell???

    This is one of the reasons I was intrigued by Swanson & Tsonis, 2009, though I think they didn’t have enough components involved yet to get down and get decadal (possibly a case of premature publication, or media mania ;)

    Comment by John P. Reisman (OSS Foundation) — 14 Aug 2009 @ 7:44 AM

  163. Not much that “WE” care about died then; the most
    prominent victims were deep-ocean microscopic foraminifera that live
    on the sea floor.

    How will this affect the numerous overfished fisheries upon which hundreds of millions of people depend?

    Comment by llewelly — 14 Aug 2009 @ 11:09 AM

  164. I agree, this topic is off the main subject, but Mark said is was very easy to show CO2 & global warming.

    150 Tamino – How?

    Comment by J. Bob — 14 Aug 2009 @ 11:09 AM

  165. Thank you for the comments, Mr. Dickens. In your opinion why do the models get the PETM wrong ? How can we improve the models ?What are some candidates for the missing physics ?

    Comment by sidd — 14 Aug 2009 @ 1:49 PM

  166. Lovelock has been saying all along that we were headed for another PETM and all we can do is sit back and build more nuclear power plants.

    Comment by Marion Delgado — 14 Aug 2009 @ 2:57 PM

  167. Hank I’m obviously talking about the Zeebe paper that is the topic of *this post*. Also of interest is the recent finding by Swanson that was largely ignored and disparaged here = their observed “… pause in warming”.

    The implication of both papers is that climate models face challenges when compared to real world observations. Since accurate modelling of natural variability is essential if we are to move on to determine the extent of warming caused by humans and possible mitigation scenarios, I’d be more comfortable with the demands for massive mitigation efforts and the claims of impending catastrophe if we could at least have models that matched up to reality in a more robust fashion.

    Your ongoing double standard for “citations” supports my point also – you and others routinely attack people here on general grounds, yet suggest the general criticism of others is misguided. Citation?
    [edit – OT and wrong in any case]

    Comment by Joe Hunkins — 14 Aug 2009 @ 3:15 PM

  168. Mr. Best
    Re:Pine Island Glacier

    I looked for this paper on the GRL site, but did not find ? Has anyone a reference to a preprint ? or a URL to the paper ?

    Comment by sidd — 14 Aug 2009 @ 4:17 PM

  169. J. Bob (164) — See any book on atmospheric physics.

    Comment by David B. Benson — 14 Aug 2009 @ 4:45 PM

  170. Is it known if the PETM had any sort of cellular structure, analogous to but presumably different from the current day Polar – Ferrel – Hadley structure? Do any of the GCMs reveal collapse of the PFH structure under future scenarios, or are such structures absolutely stable? If they show propensity for instability, what are the key triggers for destabilisation? If there was a significantly different cellular structure, or dyanamic cellular pattern/ordering existing through the PETM, might that be accompanied by strong spatial-temporal dependence of climate sensitivities (and hence accompanying geo/bio phenomena)?

    Comment by michael — 14 Aug 2009 @ 4:45 PM

  171. While appreciating Dr. Dickens comments on this thread, I do have a problem with his statement that has caused such a kerfuffle i.e.:

    In a nutshell, there appears to be something fundamentally wrong with the way temperature and carbon are linked in climate models.

    This seems ill-advised for two (linked) reasons:

    1. We don’t really know what the situation was at the time of the PETM 55 MYA. Perhaps when the situation is clearer we’ll find that the way temperature and climate is linked in climate models actually applies very well to the PETM.

    2. There’s no reason why climate models, parameterized with respect to the wealth of detail of Holocene and late Quaternary measurements and proxies, should necessarily apply to the Cenozoic era. The world was very different then. The apparent lack of expected response of Cenozoic era climate to greenhouse forcing then doesn’t necessarily mean that there is a significant problem with current modelling of climate responses to greenhouse forcing now .

    Comment by chris — 14 Aug 2009 @ 4:48 PM

  172. re #167

    Joe, Swanson (and Tsonis) didn’t “observe” “a pause in warming”! They postulated the possibility of a pause in warming….

    …and the Zeebe paper doesn’t “impl(y) that climate models face challenges when compared to real world observations”. After all, when we fully understand the PETM, we might find that climate models fit the observations rather well after all. Alternatively, there’s no reason to expect that climate models parameterized with respect to Quaternary observations/proxies, should necessarily apply to the Cenozoic era which was a rather different world.

    Your post highlights exactly the problem with the rather careless press release from Rice University. It is catnip to misrepresenters!

    Of course we should continue to improve climate model parameterization by comparison with real world observation. But neither Swanson and Tsonis, nor Zeebe et al. are necessary grounds for questioning current climate models. If anything, Zeebe et al might lend us to consider that unforeseen positive feedbacks could make climate responses to greenhouse forcing rather more problematic than models project. That’s what Dr. Dickens was trying to convey in the the press release I believe.

    Comment by chris — 14 Aug 2009 @ 5:06 PM

  173. A question for any of the researchers familiar with the paleo record —

    > the most prominent victims were deep-ocean microscopic foraminifera
    Is there any estimate of the biomass and CO2/methane they’d release, dying?

    And, of the species that didn’t disappear, how about the biomass of those that lived mostly in the depth range of the expanded zone of solution — same question, are the biologists contributing to the search for possible added CO2 and CH4?

    If a big swath of the fossil record was dissolved, how would we know?

    Comment by Hank Roberts — 14 Aug 2009 @ 6:39 PM

  174. “…what would have happened to the carbon you’re talking about? Is there a spike in accumulation of some carbon-containing material (sedimentary rock, presumably?) associated with the end of the PETM?”
    Hank Roberts — 13 August 2009 @ 1:25 PM

    “Initial results suggest that the Eocene cooling occurred much earlier, and much faster than previously assumed; summer SSTs were extremely high during the so-called Paleocene Eocene Thermal Maximum (ca. 20-24ºC, at ~55 Ma) dropping to values as low as ~5ºC only 5 Ma later. These values are in good agreement with initial dinoflagellate-based SST-trends. One hypothesis is that this dramatic cooling that happened much faster than up to now anticipated may be related to a substantial drop in pCO2 resulting from the highly efficient production and burial of large amounts of organic carbon in the huge Arctic Basin. This may have been the consequence of anoxic water column conditions in the stratified basin and the massive growth of the hydropterid fern Azolla in the surface waters of the Arctic at this time, another surprising ACEX finding.”

    “ТACEX was the first Integrated Ocean Drilling Project (IODP 302) expedition into the Arctic and recovered over 400m (1,400ft) of cores, including 200m (700ft) of Paleocene and Eocene deposits.’ explains Jonathan. ‘In the section corresponding to the earliest Middle Eocene – near the point in time when we start to see a sudden shift in CO2 levels – we found more than eight metres of core composed almost completely of a plant known as Azolla, a floating fern sometime found in suburban ponds.”
    GEO ExPro September 2007

    “An Azolla Event in the Middle Eocene – Dinoflagellate cysts, diatoms, ebridians, and silicoflagellates are common to abundant in the middle Eocene section that includes a spectacular basal layer showing massive occurrences of glochidia and massulae (megaspores) of the fresh-water hydropterid fern Azolla, suggesting strongly reduced surface-water salinity or perhaps even a brief episode of fresh-water conditions at the surface.”

    “The Paleocene to Eocene interval shows TOC values of 1 to more than 3wt%.” Scientific Drilling, Number 1, 2005 doi:10. 0 / . 00

    I plugged some very approximate numbers into a spreadsheet and came up with about 900 gigatons of carbon sequestered, so the order of magnitude is about right(i.e., 90 Gigatons wouldn’t do it, and 9000 Gt would be too much); I wouldn’t bet on my numbers being within an order of magnitude, though. Well, maybe a sixpack of Guiness; I could afford to lose that.

    Comment by Brian Dodge — 14 Aug 2009 @ 10:20 PM

  175. Well, from the little ive read of this event, the most likely mechanism for the shift may be a submarine tectonic rift/volcanism. And until the ocean circulations can be modeled with sufficient resolution for that time period, i doubt whether the models will ever be able to recreate this event accurately.

    Obviously its the continents, and their effect on ocean circulation/albedo that set the initial climate, and considering the relative stability of the various other “hot house” periods, it stands to reason that the trigger for this event, is something on the exceptional side. As opposed to a gradual tipping point being reached?

    How well is ocean circulation modeled? It seems like this would be near impossible to do in hind site?

    Comment by Mike — 14 Aug 2009 @ 10:41 PM

  176. Hello Chris (171) and Bryan (154),

    With all due respect, I think you are missing my main points (although given all the *kerfuffle* — great word btw — it’s certainly possible that I’m just not very good at making points clearly!). So, to clarify and to address several other comments, I give the following with a bit more elaboration (apologies if this is a long boring post, and I hope that people don’t pick and choose selected passages) …

    1/ In regards to using Quaternary (which includes the Holocene btw) climate variations as a template for constraining climate models for the future, there are two basic and somewhat related problems. One of these is observational; the other is conceptual. There are no clear examples in the pre-industrial Quaternary where massive amounts of carbon entered the exogenic carbon cycle (i.e., the combined ocean-atmosphere-biosphere). Yes, of course, there were definitely major changes in climate (and surface temperature) across Earth, and, yes, of course, some of these are obviously linked to changes in atmospheric pCO2. But nowhere in this part of the geological record is there compelling evidence for a warm climate (i.e., similar to today) when large quantities of carbon rapidly entered the exogenic carbon cycle from an external source (e.g., fossil fuels). Rather, in regards to Quaternary climate variations, the general consensus is that carbon was redistributed between the ocean, atmosphere and biosphere because of external forcing (e.g., changes in Earth orbital configurations). However, to my knowledge, present climate models do not have carbon fluxes as internal components to Earth’s system that respond to external forcing (i.e., the carbon fluxes are prescribed during time runs – but please correct me if I am wrong here because I have to edit these sort of papers pretty regularly). (Also, as an aside, I should stress that there are definitely ideas for where and how the carbon is redistributed). Now, one might suggest, as some of my friends and colleagues have done, that these things do not matter in terms of predicting future climate change for the next 100 years, and this may, in fact, be the case. But, please understand, there are some basic issues with trying to use observed climate change during the Quaternary to constrain existing models for predicting future climate change (i.e., adding carbon to a world where no such analog exists in last million years (probably 40 million years) and the models are not appropriately set for this anyhow (e.g., I agree with Bryan’s comments btw).

    2/ The amazing aspect of the PETM is that this extreme warming event is somehow associated with a fairly rapid and massive input of carbon to the exogenic carbon cycle from an external source. There is actually a great deal of information about the PETM, although there are also some major problems, again both observational and conceptual. There are the basic facts: we (well we think) we know the approximate temperature rise (~6 °C based on d18O, Mg/Ca, TEX86 and fossils – I can elaborate on these proxies if needed …); we also know there was a massive input of isotopically-depleted carbon (i.e., carbon depleted in 13C, similar to fossil fuels). This latter fact is readily appreciated by looking at hundreds of locations across the globe, which show a carbon isotope excursion and, in the deep-sea, carbonate dissolution. The event is wholly unlike anything in the Quaternary (and, in fact, probably at least the last 90 million years in terms of magnitude, except, of course, what is happening now). The overarching problems are that we do not know where the carbon came from (i.e., its source, mass and composition) or how it entered the exogenic carbon cycle, although there is much speculation (e.g., oxidation of peat, release of methane from seafloor, contact metamorphism of a petroleum system, etc.).

    The placement of *associated* (above) is deliberate. The latest IPCC document *Scientific Basis for Climate Change* also nicely (and fairly) dances around this issue when discussing the PETM (p. 442). The gist behind the semantics is that some data suggests that other forcing may have initiated the carbon input (i.e., it was not truly an external input of carbon, such as from the burning of fossil fuels, a carbonaceous bolide impact, contact metamorphism, etc.); rather, it involved a positive feedback. This complication, however, is subordinate to the case that the PETM was almost assuredly linked to an external source of carbon to the ocean/carbon/biosphere system, unlike anytime in the Quaternary. (To elaborate on two possibilities in this regard – initial changes to Earth’s coupled system drove warming of bottom waters and released seafloor methane or drove a change in the hydrological cycle and oxidation of peat).

    To restate earlier posts (and my quotation that led to all of this), no one has been able to explain basic temperature observations before, during, and after the PETM using a climate model. Indeed, with most existing carbon cycle models, there is no way to actually explain the event … despite the fact that it happened. (But to stress again, observations of the rock record during this time point to a greater temperature rise per unit of carbon added to the system than suggested in most existing models).

    (As an aside to Bryan, the beauty of examining the PETM from a scientific perspective is that the input (and output of carbon) occurred very fast (geologoically). There is likely no need to consider long-term changes in boundary conditions, although the precise boundary conditions at the time are important. My main point here, we probably do not need to model the entire Cenozoic to understand a short-term perturbation to the system)

    3/ From perhaps an overly simplistic view, one might consider the present input of carbon as one where the Quaternary is appropriate for setting boundary conditions (e.g., continent positions, ocean circulation, overall distributions of carbon, permutations to orbital configurations, etc.) but that carbon injection events of the early Paleogene (e.g., the PETM) are appropriate for understanding the effects of external carbon forcing (even if the carbon is a coupled external feedback). Both have conceptual issues, both are important. There is certainly a tendency for people to dismiss something that happened 55 million years ago as too distant to be used for model constraints, especially when the observations do not conform to expectations. But this is neither helpful nor good science. We have the basic facts that (a) there was a brief interval in time (the PETM) where global temperatures rose significantly and almost coincident with a massive input of carbon to the ocean and atmosphere; but (b) we cannot understand the link between temperature and carbon input during this time with existing models, either in terms of causal relationship or magnitude. Something needs to be amended (and, btw, just changing 1 to n parameters for climate sensitivity in models, while perhaps acceptable in terms of computer coding, does not give a lot of insight to the basic problems).

    4/ So where does this leave us as a scientific community studying climate change? Without doubt, from short to long records of the geological record (at least over the last 100 million years), there is almost unquestionably a link between Earth surface temperature and atmospheric pCO2. Do we have climate (and carbon cycling) models that can satisfactorily explain these links? I would argue no (and I will suggest that many of my colleagues would agree on this but I’ll let them dare enter into this crazy hornet’s nest of blogosphere politics, science and media ….). Does this mean that climate models predicting climate change on the 100 yr time scale (the immediate future) are wrong? I don’t know, because this may be an issue of time and a straightforward issue for atmospheric scientists, and where my expertise fades. I would strongly suggest, though, that the geological record indicates that there are carbon cycle feedbacks that are not incorporated in most models for climate change, at least as we can observe on the >1000 year timescale. Okay, I can see how that comment can spun all sort of ways … I’m learning ☺

    I hope this addresses things more clearly, although maybe I am just dreadful at the role of presenting science to people ….

    Comment by Jerry Dickens — 15 Aug 2009 @ 1:19 AM

  177. In response to Sidd (165) and others with some great science questions – (these are definitely more fun to consider than comments revolving around semantics, notions, emotions, politics, etc).

    Well, probably the simplest and most straightforward means to answer the science questions that have arisen in this stream is to pass along a review paper from last year (Zachos, Dickens & Zeebe, Nature, v. 451, p. 279-283). It can be downloaded at:
    (Although, I am not sure if one needs a subscription to access).

    Comment by Jerry Dickens — 15 Aug 2009 @ 1:32 PM

  178. The article is paywalled; links to the figures, and descriptions, are here:

    Comment by Hank Roberts — 15 Aug 2009 @ 2:36 PM

  179. Thanx for the Zachos et al. reference.

    They mention that the warm poles could not be due entirely to increased poleward heat flux in ocean currents, and speculate that the heating influence of polar stratospheric clouds may have played a role. Can anyone think of some paleo measurement that might confirm or refute an increase in such clouds during the PETM ? I confess that I cannot, but I hope I am wrong.

    [Response: No. The problem with the polar stratospheric clouds idea is that it has become clear that getting the requisite cloud optical thickness to make a difference is currently impossible using any known or easily extrapolatable physics. So while you can hypothesise a LW absorber in the stratosphere that does the trick, no one has any mechanism to actually produce one. Nonetheless, something was going on – and people are trying lots of different ideas to produce a similar result (no luck so far though). – gavin]

    Comment by sidd — 15 Aug 2009 @ 3:56 PM

  180. Thanks to Dr. Dickens and RC for this intriguing post and follow ups, which are clearly written and well articulated. I think the two very different types of responses to the paper and comments are really intriguing and suggest many are a lot more interested in position advocacy than more rational approaches.

    Comment by Joe Hunkins — 15 Aug 2009 @ 6:38 PM

  181. Thanx for the response. I see from the Huber reference in the Zachos paper that an oceanic heat flux on the order of 1 Petawatt is insufficient to reduce the equator to pole temperature gradient. I calculate that Petawatt scale fluxes due to precipitation into the polar regions would require rainfall on the order of 10meter/yr. I take it that there is no evidence for such huge precipitation imbalance in the record, at least I have not been able to find much.

    Comment by sidd — 16 Aug 2009 @ 2:02 AM

  182. re #176

    Many thanks for your comprehensive account Dr Dickens. If the press had access to that level of explanation/interpretation there would certainly be no possibility of misinterpretation! I don’t disagree with any of what you say. In fact the main point I raised is incorporated in your statement about your colleagues and their assessment that current climate models may be rather good for assessing the climate response to raised greenhouse gases over the coming century. I would tend to go along with that. The concern that is reinforced from your studies of the PETM is the very real (but presently unparameterizable perhaps) possibility of downstream feedbacks that might greatly amplify the warming. I guess the most well understood of these might be the warming-induced release of methane from tundra and clathrates and other currently sequestered carbon sources (e.g. peat or forest).

    Can I ask a question about your paper that concerns methane feedbacks? In both your paper and the accompanying commentary of Beerling, methane release from unknown sources is proposed as one of the putative feedback that might have amplified the warming resulting from the initial 3000 Pg release (and the subsequent longer term “pulsed” release of carbon) that initiated the PETM. Since this methane (from clathrates or swampland or permafrost) will also be 13C-depelted and presumably (once oxidised) will contribute to the effects on the carbonate-dissolution records you used to constrain the amount of carbon released, shouldn’t this “feedback” (warming-induced methane release) have already been accounted for in your analysis, if it had in fact existed?

    Or does your analysis only constrain the initial (~3000 Pg) carbon release, and any subsequent release (e.g. 13C-depleted C from methane) is not directly assessed in your analysis? I’ve read your very nice paper a couple of times, but can’t clarify this point myself!

    Comment by chris — 16 Aug 2009 @ 7:29 AM

  183. @164:

    Graph of CO2 rises. Temperature rises.

    Easy peasy.

    Comment by Mark — 16 Aug 2009 @ 8:25 AM

  184. “Now for the Paleocene, it is unlikely that changes in ice sheets were very relevant (there weren’t any to speak of”

    This view (Shackelton and Kennett, 1975) is coming under more and more scientific scrutiny in recent years. In 1980, Matthews in Poore published a paper suggesting that glacio-eustacy was the dominant driver in sharp rapid sea level changes for much of the Paleogene, even back into the Cretaceous. This hypothesis resulted from examining the relationship between the d18O proxy and the global sea level curves produced by Exxon in the late 1970’s (credited largely to Peter Vail, 1977). The hypothesis went largely un-noticed outside the petroleum geology community, and the dominant theory held that Antarctic glaciation was not initiated until the middle Miocene (ca 15 Ma). With the publication of the Haq et al. sea level curves in 1987, it came under wider recognition that large and rapid eustatic changes, if valid, presented a serious challenge to the theory that the Eocene and Paleocene were ice free. It is important to note that such rapid and large magnitude changes reported in the Haq et al. curves can only be explained by glacio-eustacy. The Haq paper was highly criticized within academia, mainly due to the lack of public access to much of the proprietary seismic data used to generate these curves, and also the widespread view that these curves were contaminated from local effects. The Matthews hypothesis continued to go largely un-noticed, except by a few workers (Stoll and Schrag, 1998) (Abreu and Anderson, 1998) (Miller et. al 2005). In recent years however, the Haq curves have been independently produced by several workers, and largely vindicated. An important recent paper by Miller et al. in 2008 looked at the passive margin along the coast of New Jersey, and demonstrates that the first order sea level cycles agree well with the Haq curves, although the absolute magnitude of the variations is somewhat less than earlier reported (although still very significant). The new work also demonstrated a good correlation between sea level and the d18O proxy, as had been asserted by Abeu and Anderson in their 1998 paper.

    This newer emerging view of glacio-eustacy is of importance to the problem of investigating even rapid events such as the PETM. First, temperature reconstructions for the Early Cenozoic are based largely on the d18O proxy, and implicit in the older reconstructions was the assumption that ice sheets during the early Cenozoic are negligible. Since the d18O proxy is sensitive to both temperature and glaciation, the temperature story gets very complicated in the presence of ice. Secondly, significant ice sheets in the hothouse climate of the Eocene, even if ephemeral, are potentially important to the feedbacks within the earth system. As Gavin states in his essay, modelers currently view these ice sheets as either non-existent, or too small to matter. That older assumption is not holding up well in recent years however. The initiation of both Antarctic and even NH glaciation is being pushed further and further back in time. An examination of the Miller (2008) curves shows rapid sea level rises and falls of over 50-75 meters on either side of the PETM. These curves present a significant challenge to anyone who insists on largely ice-free conditions near the Paleocene-Eocene boundary.


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    [Response: There’s a big difference between the early Cretaceous and the Paleocene/Eocene transition period, let alone the mid Eocene thermal max. I am unaware of any evidence for significant ice over that period (say 53 to 45 million years ago) – but maybe I just haven’t noticed. Do you have anything specific? – gavin]

    Comment by Bryan S — 17 Aug 2009 @ 9:52 AM

  185. Gavin, Yes, there is specific evidence for ice at the Paleocene/Eocene boundary and also near the Eocene Climatic Optimum (ca 51 Ma). The new sea level curves shown by Ken Miller indicate 50 meter+ rises in falls of sea level within relatively short intervals surrounding the Paleocene/Eocene boundary, and also periodically during the ECO. Such rapid sea-level changes pose an enigma, because the only known mechanism for causing sea-level changes in excess of 10m in less than 1myr is glacioeustasy (Golovchenko, 1983).

    Specific sedimentological evidence for glaciation in East Antarctica during the Eocene comes from ODP Leg 119 drill sites on the continental shelf of Przdz Bay. Site 742 in Prydz Bay recovered middle-upper Eocene massive diamictons, interpreted as water-lain till (Barron et al., 1991, Hambrey et al., 1991). The occurrence of till on the continental shelf is synchronous with the first significant occurrence of ice-rafted detritus at Leg 119 site 738 on the Kerguelen Plateau (Ehrmann, 1991, Abreu and Anderson, 1998). Evidence also exists for alpine glaciation in West Antarctica during the middle Eocene. Glacial marine sediments were recovered at CIROS-1 in the western Ross Sea which contain middle Eocene dinoflagellates (Hanna, 1994). The evidence is however, that the West Antarctic glaciation did not advance across the continental shelf during the Eocene.

    Gavin, the evidence is quite compelling that there is significant ice on the continent possibly coinciding with some of the warmest hothouse climates of the Eocene. I encourage you to read some of the references I have listed here. John Anderson, who is a respected researcher of Cenozoic Antarctic geology (and a colleague of Gerald Dickens at Rice) has compiled some of this data in his paper with the reference listed above.

    Comment by Bryan S — 17 Aug 2009 @ 4:02 PM

  186. Worth a look — consolidated page on ocean drilling:

    (found following the Anderson reference forward in time via some of the many citing papers)

    Comment by Hank Roberts — 17 Aug 2009 @ 4:15 PM

  187. and this:

    “… The sediment records are studied to gain insights into palaeo glacial dynamics of the East Antarctic Ice Sheet from a marine perspective by the reconstruction of glaciomarine processes in the past. The study area is bordered by the Lambert Glacier-Amery Ice Shelf system that drains about 20% of the East Antarctic Ice Sheet and is considered to be representative for the behaviour of the whole East Antarctic Ice Sheet. The retrieved sediment cores allow the reconstruction of ice-sheet dynamics at different time scales, comprising high-resolution Holocene records, the time interval of the latest glacial-interglacial cycle during the past 130 kyr, and one long-term record back to the mid-Pliocene. Special emphasis will be focussed on the provenance and dispersal of ice-rafted debris (IRD) and the distibution of contourites in space and time, as indicators of palaeo iceberg drift tracks and AABW activity….”

    Comment by Hank Roberts — 17 Aug 2009 @ 6:18 PM

  188. (PS, yes, that’s recent; I’m still looking for cores going through the PETM; anyone have a specific pointer to something available online?)

    Comment by Hank Roberts — 17 Aug 2009 @ 6:22 PM

  189. Ah, too easy:

    Comment by Hank Roberts — 17 Aug 2009 @ 6:24 PM

  190. Is it really that hard to figure out where the carbon came from? Aren’t the possibilities rather limited?

    Comment by Jackie — 17 Aug 2009 @ 11:34 PM

  191. What difference does the rate of change (of rate of change) make, if any, with feedbacks other than ocean pH? I think I understand that with a geologically typical CO2 increase, the ocean pH doesn’t change very much because other chemical reactions use up the ions as fast as the CO2 dissolves. But with our extreme rapid increase of CO2 that doesn’t work, so the carbonic acid accumulates.

    I know there were some suggestions a comet or asteroid impact into an area rich in carbon could kick off something like the PETM event if it happened on top of a normal warm stretch. Anything more on that?

    Is this still current thinking?

    Comment by Hank Roberts — 17 Aug 2009 @ 11:35 PM

  192. Re: Cenozoic (last 65 million year)
    No. 55 mya, (65 is the KT, 10 mya after is PETM).

    Comment by Ed Pardo — 17 Aug 2009 @ 11:56 PM

  193. Glacioeustatic Control of Sea-Level: Eocene Hothouse Climate

    I’ve added a few more references from my comment #185 and fixed the format for the previous ones listed. Many papers and reports (many over 20 years old) documenting evidence of at least ephemeral Antarctic ice sheets during the Eocene have not been widely read outside the geology community, and it is my hope that this accumulating body of information in support of the Matthews hypothesis will become better appreciated in the larger earth systems world. For climate scientists and modelers without a strong working knowledge of seismic stratigraphy, a good place to begin is with the 2008 Miller et al. paper and work backward to some of the older literature.


    Abreu, V.S., and Anderson J.B., 1998 Glacial Eustacy During the Cenozoic:Sequence Stratigraphic Implications. American Association of Petroleum Geologists Bulletin, V. 82, No. 7, P. 1385-1400

    Barron, E. J., B. Larsen, and J. G. Baldauf, 1991, Evidence for late Eocene to early Oligocene Antarctic glaciation and observations on late Neogene glacial history of Antarctica: results from Leg 119: Proceedings of the Ocean Drilling Program Scientific Results, v. 119, p. 869-894.

    Ehrmann, W. U., 1991, Implications of sediment composition on the southern Kerguelen Plateau for paleoclimate and depositional environment: Proceedings of the Ocean Drilling Program Scientific Results, v. 119, p. 185-210.

    Hambrey, M. J., W. U. Ehrmann, and B. Larsen, 1991, The Cenozoic glacial record from the Prydz Bay continental shelf, East Antarctica: Proceedings of the Ocean Drilling Program Scientific Results, v. 119, p. 77-132.

    Hannah, M. J., 1994, Eocene dinoflagellates from CIROS-1 drillhole, McMurdo Sound, Antarctica: Terra Antarctica, v. 1, p. 371-372.

    Haq, B. U., J. Hardenbol, and P. R. Vail. 1987. Chronology of fluctuating sea levels since the Triassic (250 million years ago to present). Science 235: 1156-1167.

    Kennett, J. P. 1977. Cenozoic evolution of Antarctic glaciation, the Circum-Antarctic Ocean, and their impact on global paleoceanography. Journal of Geophysical Research 82:3843-3860

    Matthews, R. K., and R. Z. Poore. 1980. Tertiary d18O record and glacioeustatic sea-level fluctuations. Geology 8:501-504.

    Miller, K. G., J. D. Wright, and J. V. Browning. 2005. Visions of ice sheets in a greenhouse world. Marine Geology 217:215-231

    Miller, K.G., Wright, J.D., Katz, M.E., Browning, J.V., Cramer, B.S., Wade, B.S. Mizintseva, S.F., 2008. A View of Antarctic Ice-Sheet Evolution from Sea-Level and Deep-Sea Isotope Changes During the Late Cretaceous-Cenozoic. In Cooper, A. K., P. J. Barrett, H. Stagg, B. Storey, E. Stump, W. Wise, and the 10th ISAES editorial team, eds. (2008). Antarctica: A Keystone in a Changing World. Proceedings of the 10th International Symposium on Antarctic Earth Sciences. Washington, DC: The National Academies Press

    Pitman, W.C., III, and X. Golovchenko, 1983. The effect of sea-level Change on the shelf edge and slope of passive margins. Special Publication 33, pp. 41-58. Society of Economic Paleontologists and Mineralogists.

    Shackleton, N. J., and J. P. Kennett. 1975. Paleotemperature history of the Cenozoic and the initiation of Antarctic glaciation, oxygen and carbon isotope analyses in DSDP sites 277, 279, and 281. In Init. Reports DSDP,eds. J. P. Kennett, R. E. Houtz et al., pp. 743-755. Washington, D.C.:U.S. Government Printing Office.

    Stoll, H. M., and D. P. Schrag. 1996. Evidence for glacial control of rapid sea level changes in the Early Cretaceous. Science 272:1771-1774.

    Vail, P. R., R. M. Mitchum, R. G. Todd, J. M. Widmier, S. Thompson III, J.B. Sangree, J. N. Bubb, and W. G. Hatlelid. 1977. Seismic stratigraphy and global changes of sea level. In Seismic Stratigraphy—Applications to Hydrocarbon Exploration, ed. C. E. Payton. Memoirs of the American Association of Petroleum Geologists 26:49-205. Tulsa, OK: AAPG.

    Comment by Bryan S — 18 Aug 2009 @ 8:23 AM

  194. Thanx for the references to glaciation around PETM.

    1) Is it possible that albedo feedback might have been a larger contributor ?

    2) Would a larger albedo feedback help explain either the magnitude of temperature rise or low pole to equator temperature gradient ?

    3)A letter to Nature in 2006 by Nunes and Norris indicates that ocean overturning and deepwater formation switched from S to N hemisphere at the beginning of PETM. Has there been further work in that area ?
    (Nature Letters v 439, pp60-64, 2006)

    Comment by sidd — 18 Aug 2009 @ 11:02 AM

  195. Sidd, yes:

    Abrupt reversal in ocean overturning during the Palaeocene/Eocene warm period
    F Nunes, RD Norris – Nature, 2006 –
    Cited by 21 (including names you’ve seen here at RC)

    Comment by Hank Roberts — 18 Aug 2009 @ 12:59 PM

  196. PS, from the above search, a reminder how complicated rapid change gets:

    “… Despite acidification of the ocean there was not a productivity crisis among calcifying phytoplankton.”

    Sounds promising. Read on …

    “… maintenance of stable or increased productivity there likely reflects increased nutrient inventories of the ocean. Increased nutrient inventories could have resulted from climatically enhanced weathering ….”

    Which, I venture, is a way of saying, good luck holding onto your topsoil and gravel.

    I’ve come across that before, e.g.
    Page 1
    doi: 10.1130/G23261A.1
    Birger Schmitz and Victoriano Pujalte

    Abrupt increase in seasonal extreme precipitation at the Paleocene-Eocene


    Now again the PETM was fast the way geology is fast, not fast the way the anthropocene event is fast.

    But does this suggest we might not see ocean pH change as projected, because we might see a rapid increase in “weathering” as in peak storm erosion increasing available nutrients in the ocean? Not to mention all that fertilizer ….

    Comment by Hank Roberts — 19 Aug 2009 @ 2:55 PM

  197. Oh, for the latter, the abstract:

    and some subsequent cites there too.

    Comment by Hank Roberts — 19 Aug 2009 @ 2:57 PM

  198. Following citing papers — oh my, the further in you go the bigger it gets:
    In this issue of PNAS, Schumann et al. (4) report evidence for new microorganisms that appeared and disappeared with the PETM, signaling another specific ecological response to the biogeochemical changes associated with this extreme warming event….

    Nature doesn’t throw adaptations away, so odds are the genes highly favored during the PETM are conserved at low levels.

    Comment by Hank Roberts — 19 Aug 2009 @ 3:00 PM

  199. Geez Climate scientists – and science journal editors in particular – have to realise the political and social context of their work. If you’re studying an obscure subspecies of termite then choose your own title. But if the future of civilization depends on responding urgently to Global Warming – to give momentum to global warming deniers at this point of time by loose phraseology in paper titles is foolish, frustrating and unethical.

    Comment by ruckrover — 21 Aug 2009 @ 6:36 AM

  200. Beside the small typo (65 to 55), overall good article.

    I suggest a look at overall the maps shows what happens of oceans. The change from the KT to the 50 mya (not 55 mya) is important at beginning the Eocene starts.

    The PETM is a small period, cools then warm again but over a larger period. Climate changes becomes of the oceans are major new currents.

    Comment by Ed Pardo — 21 Aug 2009 @ 12:08 PM

  201. Theo: Mars is warming

    PETM, more:

    Multiple early Eocene hyperthermals: Their sedimentary expression on the New Zealand continental margin and in the deep sea

    Micah J. Nicolo*,1, Gerald R. Dickens1, Christopher J. Hollis2 and James C. Zachos3

    “[PETM]… a geologically brief interval characterized by massive influx of isotopically light carbon, extreme changes in global climate, and profound variations in Earth system processes. An outstanding issue is whether it was an isolated event, or the most prominent example of a recurring phenomenon. Recent studies of condensed deep-sea sections support the latter, but this finding remains uncertain. Here we present and discuss lithologic and carbon isotope records across two lower Eocene outcrops on South Island, New Zealand…. The presence of five intervals with similar systemic responses in different environments suggests a mechanism that repeatedly injected large masses of 13 C-depleted carbon during the early Eocene.”

    I always like to look on the optimistic side. It looks like the enhanced erosion and sediment transport from the continents to the ocean may have neutralized the pH spikes around previous episodes of rapid CO2 increase.

    As always, rate of change/timing is different at present — we’re increasing CO2 much, much faster than in past events; ocean pH is rising correspondingly much faster, not leaving time for chemical buffering to moderate the change.

    I’d guess even the eventual massive increase in erosion typical of past events won’t happen fast enough to prevent a serious ocean dieoff.

    Comment by Hank Roberts — 27 Aug 2009 @ 1:17 PM

  202. PETM, new:

    Rapid Paleoenvironmental Change during the Paleocene-Eocene Thermal Maximum (PETM), Bighorn Basin, WY*
    Mary J. Kraus, Daniel Woody, Jon Smith, and Stephen Hasiotis
    Search and Discovery Article #50160 (2009)
    Posted January 16, 2009
    *Adapted from oral presentation at AAPG Annual Convention, San Antonio, TX, April 20-23, 2008


    Comment by Hank Roberts — 4 Sep 2009 @ 10:40 AM


    Liu, S. C., C. Fu, C.-J. Shiu, J.-P. Chen, and F. Wu (2009), Temperature dependence of global precipitation extremes, Geophys. Res. Lett., 36, L17702, doi:10.1029/2009GL040218.

    “Data from the Global Precipitation Climatology Project (GPCP) covering the period 1979–2007 are examined for changes of precipitation extremes as a function of global mean temperature by using a new method ….

    … suggesting that the risk of extreme precipitation events due to global warming is substantially greater than that estimated by the climate models.”


    Comment by Hank Roberts — 5 Sep 2009 @ 2:48 PM

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