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PETM Weirdness

Filed under: — gavin @ 10 August 2009

The Paleocene-Eocene Thermal Maximum (PETM) was a very weird period around 55 million years ago. However, the press coverage and discussion of a recent paper on the subject was weirder still.


For those of you not familiar with this period in Earth’s history, the PETM is a very singular event in the Cenozoic (last 65 million years). It was the largest and most abrupt perturbation to the carbon cycle over that whole period, defined by an absolutely huge negative isotope spike (> 3 permil in 13C). Although there are smaller analogs later in the Eocene, the size of the carbon flux that must have been brought into the ocean/atmosphere carbon cycle in that one event, is on a par with the entire reserve of conventional fossil fuels at present. A really big number – but exactly how big?

The story starts off innocently enough with a new paper by Richard Zeebe and colleagues in Nature Geoscience to tackle exactly this question. They use a carbon cycle model, tuned to conditions in the Paleocene, to constrain the amount of carbon that must have come into the system to cause both the sharp isotopic spike and a very clear change in the “carbonate compensation depth” (CCD) – this is the depth at which carbonates dissolve in sea water (a function of the pH, pressure, total carbon amount etc.). There is strong evidence that the the CCD rose hundreds of meters over the PETM – causing clear dissolution events in shallower ocean sediment cores. What Zeebe et al. come up with is that around 3000 Gt carbon must have been added to the system – a significant increase on the original estimates of about half that much made a decade or so ago, though less than some high end speculations.

Temperature changes at the same time as this huge carbon spike were large too. Note that this is happening on a Paleocene background climate that we don’t fully understand either – the polar amplification in very warm paleo-climates is much larger than we’ve been able to explain using standard models. Estimates range from 5 to 9 deg C warming (with some additional uncertainty due to potential problems with the proxy data) – smaller in the tropics than at higher latitudes.

Putting these two bits of evidence together is where it starts to get tricky.

First of all, how much does atmospheric CO2 rise if you add 3000 GtC to the system in a (geologically) short period of time? Zeebe et al. did this calculation and the answer is about 700 ppmv – quite a lot eh? However, that is a perturbation to the Paleocene carbon cycle – which they assume has a base CO2 level of 1000 ppm, and so you only get a 70% increase – i.e. not even a doubling of CO2. And since the forcing that goes along with an increase in CO2 is logarithmic, it is the percent change in CO2 that matters rather than the absolute increase. The radiative forcing associated with that is about 2.6 W/m2. Unfortunately, we don’t (yet) have very good estimates of background CO2 levels in Paleocene. The proxies we do have suggest significantly higher values than today, but they aren’t precise. Levels could have been less than 1000 ppm, or even significantly more.

If (and this is a key assumption that we’ll get to later) this was the only forcing associated with the PETM event, how much warmer would we expect the planet to get? One might be tempted to use the standard ‘Charney’ climate sensitivity (2-4.5ºC per doubling of CO2) that is discussed so much in the IPCC reports. That would give you a mere 1.5-3ºC warming which appears inadequate. However, this is inappropriate for at least two reasons. First, the Charney sensitivity is a quite carefully defined metric that is used to compare a certain class of atmospheric models. It assumes that there are no other changes in atmospheric composition (aerosols, methane, ozone) and no changes in vegetation, ice sheets or ocean circulation. It is not the warming we expect if we just increase CO2 and let everything else adjust.

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.

Now for the Paleocene, it is unlikely that changes in ice sheets were very relevant (there weren’t any to speak of). But changes in vegetation, ozone, methane and aerosols (of various sorts) would certainly be expected. Estimates of the ESS taken from the Pliocene, or from the changes over the whole Cenozoic imply that the ESS is likely to be larger than the Charney sensitivity since vegetation, ozone and methane feedbacks are all amplifying. I’m on an upcoming paper that suggests a value about 50% bigger, while Jim Hansen has suggested a value about twice as big as Charney. That would give you an expected range of temperature increases of 2-5ºC (our estimate) or 3-6ºC (Hansen) (note that uncertainty bands are increasing here but the ranges are starting to overlap with the observations). ALl of this assumes that there are no huge non-linearities in climate sensitivity in radically different climates – something we aren’t at all sure about either.

But let’s go back to the first key assumption – that CO2 forcing is the only direct impact of the PETM event. The source of all this carbon has to satisfy two key constraints – it must be from a very depleted biogenic source and it needs to be relatively accessible. The leading candidate for this is methane hydrate – a kind of methane ice that is found in cold conditions and under pressure on continental margins – often capping large deposits of methane gas itself. Our information about such deposits in the Paleocene is sketchy to say the least, but there are plenty of ideas as to why a large outgassing of these deposits might have occurred (tectonic uplift in the proto-Indian ocean, volcanic activity in the North Atlantic, switches in deep ocean temperature due to the closure of key gateways into the Arctic etc.).

Putting aside the issue of the trigger though, we have the fascinating question of what happens to the methane that would be released in such a scenario. The standard assumption (used in the Zeebe et al paper) is that the methane would oxidise (to CO2) relatively quickly and so you don’t need to worry about the details. But work that Drew Shindell and I did a few years ago suggested that this might not quite be true. We found that atmospheric chemistry feedbacks in such a circumstance could increase the impact of methane releases by a factor of 4 or so. While this isn’t enough to sustain a high methane concentration for tens of thousands of years following an initial pulse, it might be enough to enhance the peak radiative forcing if the methane was being released continuously over a few thousand years. The increase in the case of a 3000 GtC pulse would be on the order of a couple of W/m2 – for as long as the methane was being released. That would be a significant boost to the CO2-only forcing given above – and enough (at least for relatively short parts of the PETM) to bring the temperature and forcing estimates into line.

Of course, much of this is speculative given the difficulty in working out what actually happened 55 million years ago. The press response to the Zeebe et al paper was, however, very predictable.

The problems probably started with the title of the paper “Carbon dioxide forcing alone insufficient to explain Palaeocene–Eocene Thermal Maximum warming” which on it’s own might have been unproblematic. However, it was paired with a press release from Rice University that was titled “Global warming: Our best guess is likely wrong”, containing the statement from Jerry Dickens that “There appears to be something fundamentally wrong with the way temperature and carbon are linked in climate models”.

Since the know-nothings agree one hundred per cent with these two last statements, it took no time at all for the press release to get passed along by Marc Morano, posted on Drudge, and declared the final nail in the coffin for ‘alarmist’ global warming science on WUWT (Andrew Freedman at WaPo has a good discussion of this). The fact that what was really being said was that climate sensitivity is probably larger than produced in standard climate models seemed to pass almost all of these people by (though a few of their more astute commenters did pick up on it). Regardless, the message went out that ‘climate models are wrong’ with the implicit sub-text that current global warming is nothing to worry about. Almost the exact opposite point that the authors wanted to make (another press release from U. Hawaii was much better in that respect).

What might have been done differently?

First off, headlines and titles that simply confirm someone’s prior belief (even if that belief is completely at odds with the substance of the paper) are a really bad idea. Many people do not go beyond the headline – they read it, they agree with it, they move on. Also one should avoid truisms. All ‘models’ are indeed wrong – they are models, not perfect representations of the real world. The real question is whether they are useful – what do they underestimate? overestimate? and are they sufficiently complete? Thus a much better title for the press release would have been more specific “”Global warming: Our best guess is likely too small” – and much less misinterpretable!

Secondly, a lot of the confusion is related to the use of the word ‘model’ itself. When people hear ‘climate model’, they generally think of the big ocean-atmosphere models run by GISS, NCAR or Hadley Centre etc. for the 20th Century climate and for future scenarios. The model used in Zeebe et al was not one of these, instead it was a relatively sophisticated carbon cycle model that tracks the different elements of the carbon cycle, but not the changes in climate. 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. Thus nothing in the paper related to the commonly accepted ‘climate models’ at all, yet most of the commentary made the incorrect association.

To summarise, there is still a great deal of mystery about the PETM – the trigger, where the carbon came from and what happened to it – and the latest research hasn’t tied up all the many loose ends. Whether the solution lies in something ‘fundamental’ as Dickens surmises (possibly related to our basic inability to explain the latitudinal gradients in any of the very warm climates) , or whether it’s a combination of a different forcing function combined with more inclusive ideas about climate sensitivity, is yet to be determined. However, we can all agree that it remains a tantalisingly relevant episode of Earth history.


203 Responses to “PETM Weirdness”

  1. 1
    savegaia says:

    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.

  2. 2
    David Horton says:

    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”‘.

  3. 3
    Chris Colose says:

    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.

  4. 4
    Matt Andrews says:

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

  5. 5
    Steve Fish says:

    Gavin:

    Wow!

    Steve

  6. 6
    Oakden Wolf says:

    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

  7. 7
    savegaia says:

    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,’
    http://www.sciencecentric.com/news/article.php?q=09062320-nickel-isotope-may-be-methane-producing-microbe-biomarker

  8. 8
    John Mashey says:

    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?

  9. 9
    Hank Roberts says:

    If Gavin will allow a couple of asides
    — some notes on the press release cluster*ck:

    http://scienceblogs.com/stoat/2009/07/communicating_science.php#comment-1779943
    http://scienceblogs.com/stoat/2009/07/communicating_science.php#comment-1781410
    with a pointer to
    http://scienceblogs.com/islandofdoubt/2009/07/gaps_in_climate_knowledge_oh_n.php?

    (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):

    http://www.soest.hawaii.edu/oceanography/faculty/mackenzie/mackenzie_SOCM.html

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

  10. 10
    dhogaza says:

    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 ….

  11. 11
    Hank Roberts says:

    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:
    http://answers.google.com/answers/threadview?id=350436

  12. 12
    coby says:

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

  13. 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.

  14. 14
    Mark J. Fiore says:

    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

  15. 15

    #8 John Mashey

    How about ‘Spin-Cycle Science’

  16. 16
    Mike Coombes says:

    Re #8

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

  17. 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.

  18. 18
    Rene says:

    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.

  19. 19
    pete best says:

    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.

  20. 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.

  21. 21
    pete best says:

    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.

  22. 22
    S2 says:

    Re. 20:

    Chinese whisper Science. I like that!

  23. 23
    seb says:

    Excellent post.

    The perils of journalism covering science.

    http://www.phdcomics.com/comics/archive/phd051809s.gif

  24. 24
    Adam says:

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

  25. 25
    David Heigham says:

    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.

  26. 26
    Mark says:

    “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.

  27. 27
    pete best says:

    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.

  28. 28
    David Wilson says:

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

    a minor quibble on an excellent post

  29. 29
    Doctor K says:

    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.

  30. 30
    Mark says:

    “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?

  31. 31
    Mark says:

    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.

  32. 32
    Walter Manny says:

    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]

  33. 33
    Dean says:

    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.

  34. 34
    Walter Manny says:

    Gavin, “almost certainly” what?

  35. 35
    Mark says:

    “Perhaps I misunderstand the proposed headline.

    [Response: Almost certainly. -gavin]”

    One would presume.

  36. 36
    Ike Solem says:

    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:

    http://www.rightpundits.com/?p=4304

    http://blogs.usatoday.com/sciencefair/2009/07/could-we-be-wrong-about-global-warming.html

    *Doyle Rice, by the way, also is portraying the low temps in July in the northwest as “a problem for global warming proponents”: http://www.usatoday.com/weather/climate/2009-08-10-july-climate-report_N.htm – 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.

    http://www.dailytech.com/Study+Finds+Global+Climate+Models+May+Be+Missing+Something/article15706.htm

    http://www.labnews.co.uk/laboratory_article.php/4628/2/global-warming:-are-the-models-wrong

    http://www.globalresearch.ca/index.php?context=va&aid=14536

    http://canadafreepress.com/index.php/article/12954

    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:

    http://www.sciencedaily.com/releases/2009/08/090807091435.ht
    “Spectacular Melting Of The Largest French Glacier”

    http://www.sciencedaily.com/releases/2009/08/090807154404.htm
    “Psychological Factors Help Explain Slow Reaction To Global Warming”

    http://www.sciencedaily.com/releases/2009/08/090811091832.htm
    “Climate Models Confirm More Moisture In Atmosphere Attributed To Humans”

    http://www.sciencedaily.com/releases/2009/08/090806141716.htm
    “Ozone Depletion Reduces Ocean Carbon Uptake”

    http://www.sciencedaily.com/releases/2009/08/090806141512.htm
    “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…

    http://www.sciencedaily.com/releases/2009/08/090806112609.htm
    “Researchers Reveal Ocean Acidification At Station ALOHA In Hawaii”

    http://www.sciencedaily.com/releases/2009/08/090807103907.htm
    “Highest Ever Winter Water Temperatures Recorded Off Tasmania”

    http://www.sciencedaily.com/releases/2009/07/090725120303.htm
    “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?

  37. 37
    Doctor K says:

    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.

  38. 38
    pete best says:

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

    http://en.wikipedia.org/wiki/File:LateTriassicGlobal.jpg

    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.

  39. 39
    pete best says:

    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.

  40. 40

    Re #8

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

    Cheers, Alastair.

  41. 41
    frederic says:

    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

  42. 42
    Paul K in Seattle says:

    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.

  43. 43
    Mark says:

    “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”?

    Nobody.

    “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.

  44. 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.

  45. 45
    Jim Galasyn says:

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

    Such as?

  46. 46
    D Robinson says:

    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.

  47. 47
    Hank Roberts says:

    Another suggestion for John Mashey:

    Rendition.

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

    http://home.bway.net/drstu/chapter.html

    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.

  48. 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

  49. 49
    Doctor K says:

    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.

  50. 50
    Theo Hopkins says:

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


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