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A Scientific Debate

Filed under: — mike @ 13 April 2015

Guest posting from Bill Ruddiman, University of Virginia

Recently I’ve read claims that some scientists are opposed to AGW but won’t speak out because they fear censure from a nearly monolithic community intent on imposing a mainstream view. Yet my last 10 years of personal experience refute this claim. This story began late in 2003 when I introduced a new idea (the ‘early anthropogenic hypothesis’) that went completely against a prevailing climatic paradigm of the time. I claimed that detectable human influences on Earth’s surface and its climate began thousands of years ago because of agriculture. Here I describe how this radically different idea was received by the mainstream scientific community.

Was my initial attempt to present this new idea suppressed? No. I submitted a paper to Climatic Change, then edited by Steve Schneider, a well-known climate scientist and AGW spokesman. From what I could tell, Steve was agnostic about my idea but published it because he found it an interesting challenge to the conventional wisdom. I also gave the Emiliani lecture at the 2003 December American Geophysical Union (AGU) conference to some 800 people. I feel certain that very few of those scientists came to my talk believing what my abstract claimed. They attended because they were interested in a really new idea from someone with a decent career reputation. The talk was covered by many prominent media sources, including the New York Times and The Economist. This experience told me that provocative new ideas draw interest because they are provocative and new, provided that they pass the key ‘sniff test’ by presenting evidence in support of their claims.

Did this radical new idea have difficulty receiving research funding? No. Proposals submitted to the highly competitive National Science Foundation (NSF) with John Kutzbach and Steve Vavrus have been fully funded since 2004 by 3-year grants. Even though the hypothesis of early anthropogenic effects on climate has been controversial (and still is for some), we crafted proposals that were carefully written, tightly reasoned, and focused on testing the new idea. As a result, we succeeded against negative funding odds of 4-1 or 5-1. One program manager told me he planned to put our grant on a short list of ‘transformational’ proposals/grants that NSF had requested. That didn’t mean he accepted our hypothesis. It meant that he felt that our hypothesis had the potential to transform that particular field of paleoclimatic research, if proven correct.

Were we able to get papers published? Yes. As any scientist will tell you, this process is rarely easy. Even reviewers who basically support what you have to say will rarely hand out ‘easy-pass’ reviews. They add their own perspective, and they often point out useful improvements. A few reviews of the 30-some papers we have published during the last 11 years have come back with extremely negative reviews, seemingly from scientists who seem deeply opposed to anything that even hints at large early anthropogenic effects. While these uber-critical reviews are discouraging, I have learned to put them aside for a few days, give my spirits time to rebound, and then address the criticisms that are fair (that is, evidence-based), explain to the journal editor why other criticisms are unfair, and submit a revised (and inevitably improved) paper. Eventually, our views have always gotten published, although sometimes only after considerable effort.

The decade-long argument over large early anthropogenic effects continues, although recent syntheses of archeological and paleoecological data have been increasingly supportive. In any case, I continue to trust the scientific process to sort this debate out. I suggest that my experience is a good index of the way the system actually operates when new and controversial ideas emerge. I see no evidence that the system is muffling good new ideas.

54 Responses to “A Scientific Debate”

  1. 1
    Windchaser says:

    I hate to say it, but the inevitable response from “skeptics” will be that the climate science community only regularly blocks new conservative ideas.

    In short, many of them will doubt that the “early anthropogenic hypothesis” was ever controversial, since they believe or feel that climate scientists are predisposed to some liberal agenda.

  2. 2
    Steve Fish says:

    Bill Ruddman:

    Science deniers of, for example, global warming and evolutionary theory, often back up their intellectually vacant arguments with a conspiracy theory. Your phrase- “censure from a nearly monolithic community intent on imposing a mainstream view” -is a statement of one of the common bogus theories and it is an extraordinary claim that requires extraordinary evidence. The assertion that tens of thousands of climate researchers worldwide, in more than twenty nations, are being forced into lockstep without any complaint is, in my experience, often evidenced by a word of mouth description of a single, unknown scientist who makes the claim. Amazing!

    Steve

  3. 3

    So explain why I can’t get my paper published, Dr. Ruddiman–and why 8 of the 12 journals I submitted it to never even bothered to send it out for peer review.

  4. 4

    Windchaser, that’s probably true, but they are thereby giving their game away since scientific ideas aren’t inherently ‘conservative’ or ‘liberal.’ Their determination to make them ‘be so’ is clear evidence of favoring political ideology over science–and is not hard for most folks to understand.

  5. 5
    Jai Mitchell says:

    I have yet to see a thorough analysis of what the Mt Tambora eruption effect would have been in an environment where CH4 atmospheric abundance was 450 ppbv and CO2 abundance was 240 ppmv. Without access to Dr. David Archer’s CLIMBER-2 ice sheet nucleation model. I ‘believe’ that there is a reasonable likelihood that this event in 1816, coincident with the Maunder Minimum, ‘could’ have formed a permanent ice sheet in North America that would still exist today. Has anyone done this analysis in the published record?

    Thanks!

  6. 6
    Bill DeMott says:

    Barton Paul Levenson–When I review grants and manuscripts, I often support work where I think that the hypotheses are unlikely, but the science is strong and innovative. I also sometimes vote against work that agrees with my own studies, but has low quality science. Does you research make a significant advance in science and do you do a good job of integrating you papers with the scientific literature? These are issues to consider. If the editors did not sent your manuscripts out for peer review, I think that they own you a few lines of explanation. Were you able to revise your manuscript in response to the reviewers’ critiques for the 4 journals that rejected after peer-review? I have seen quite a few manuscripts and grant proposals that have been resubmitted without taking into account the critiques that caused rejection in the first place.

  7. 7
    Hank Roberts says:

    It’s interesting to watch John Baez’s interactions at the Azimuth Project with people who have draft papers needing help. Follow on from this point for one good example:
    https://johncarlosbaez.wordpress.com/2014/06/24/el-nino-project-part-2/#comment-65707

    down through

    The bottom line is that I am in no hurry to get it published.

    Okay. So far you seem to be showing little interest in having me, or the rest of the Azimuth gang, help you get it published. If we did this, I think we’d start by performing statistical tests and examining the energy flows to see if we can make a strong case for this theory. It turned out we could, then we’d help you rewrite the paper to include that material, and also adjust the style to maximize the chance of getting in some specific journal (to be determined as soon as possible).

    In that thread he gives serious pointers to the process of getting the paper suitable for submission to a specific journal — and it’s clear that shape differs for each journal.

  8. 8
    John Mashey says:

    For those interested in more, see Bill’s 2013 AGU Tyndall Lecture, fortunately made available later online.

  9. 9

    The story of the above post fits to my experience. I have been very critical of our abilities to remove non-climatic changes from climate station data. The least I can say is that it did not hurt my career, I would think it helped a lot.

    Unclear thinking, having flimsy evidence, overstating your case, that is bad for a scientist. An interesting challenge is welcome. You will naturally be challenged, but that is good, it would be weird and bad for science if it were different.

    More at Variable Variability: How climatology treats sceptics.

  10. 10
    R. Gates says:

    An excellent guest post. I’ve followed your work for some years and it must be rewarding for you to see the gradual evolution in more wide acceptance of your ideas. Though of course still controversial in some quarters as many won’t even accept that the term Anthropocene has validity, your story is at the core of the scientific process. Suggest a hypothesis, back it up with evidence, allow wide review (passing the “sniff” test multiple times, and let honest skeptical scientists consider the merits.

  11. 11
    Steve Metzler says:

    @4 Jai:

    Not quite sure what you’re getting at. Are you saying *if* Tambora went off about 150 years previous than it actually did, during the Maunder Minimum instead of 1815 – 1816, that the CO2 level was 240ppm and CH4 was 450ppb then? But they weren’t anywhere near those levels. CO2 was ~270ppm, and CH4 was ~600ppb during the Maunder Minimum. Source:

    http://cfpub.epa.gov/eroe/index.cfm?fuseaction=detail.viewPDF&ch=46&lShowInd=0&subtop=342&lv=list.listByChapter&r=239797

    And in 1815, during the *Dalton* Minimum when Tambora erupted, CO2 was at ~284ppm, and CH4 ~700ppb. Source for finer grained CO2:

    http://www.tellusb.net/index.php/tellusb/article/viewFile/15331/17176

    AFAICT, during the last 800,000 years or so, the only time CO2 would have been as low as 240ppm is *coming out of a glacial maximum*, on the rebound to 270 – 290 ppm.

  12. 12
    Mal Adapted says:

    Steve Fish:

    The assertion that tens of thousands of climate researchers worldwide, in more than twenty nations, are being forced into lockstep without any complaint is, in my experience, often evidenced by a word of mouth description of a single, unknown scientist who makes the claim. Amazing!

    For that matter, the conspiracy would have had to start at least 200 years ago, and would require that Joseph Fourier, John Tyndall, et al. had secret left-wing agendas.

    Yet reality-based people can’t make headway against such risible nonsense because we “don’t know how to communicate”. Makes me question whether there’s any point in trying.

  13. 13
    Hank Roberts says:

    … You must decide where to submit your paper. The most prestigious journals are named after abstract nouns and are distinguished by how much they loathe you, personally. Submissions to these journals are generally declined without review by power-drunk “editors”, who protect the delicate eyes of scientific reviewers from your monstrous output. You have poor decision-making skills (why else are you a scientist?), so you decide to prepare your manuscript for submission to Abstract Noun.

    4. Because Abstract Noun believes that the scientific community has not yet been informed of the “internet”, they justify very restrictive word limits on the grounds of “journal space”, as though a “journal” were a thing on paper that people read….

    5. Abstract Noun rejects your paper. If they are kind, they do this outright, explaining helpfully that while your work may be correct, it certainly is not interesting. If not, they find two or three reviewers, one of whom will be unfamiliar with your subject area but toweringly irate at its very existence. Abstract Noun regrets that the reviewers have highlighted serious flaws in your paper and are now undergoing extensive therapy for PTSD. That is, unless your paper is about the global warming “hiatus”, in which case it will be immediately accepted….

    6. The second tier of journals are generally published by reputable scientific societies, and are sometimes referred to as “Society Journals”. I love this because it makes me think of journals with elaborate surnames swanning about country houses …. No two journals have the same length or formatting requirements, which means you must risk the soporific boredom of the Supplementary Material for results that should now be included in the main text. You will also find out that all of your figures are the wrong size and color. By this time you will have misplaced the code that generates them.

    7. Definitely a Journal and Not Something Else sends your work out for peer-review. You grow up, get married, maybe have a kid or two, all while wondering what ever happened to that paper. Maybe you are truly without peer, limiting the pool ….

    http://marvelclimate.blogspot.com/2015/02/reviews-and-regrets.html

  14. 14
    Rob Ellison says:

    ‘Science advances one funeral at a time.’ Max Planck

    ‘The new paradigm of an abruptly changing climatic system has been well established by research over the last decade, but this new thinking is little known and scarcely appreciated in the wider community of natural and social scientists and policy-makers.’ http://www.nap.edu/openbook.php?record_id=10136&page=1

    The US National Academy of Sciences (NAS) defined abrupt climate change as a new climate paradigm as long ago as 2002. A paradigm in the scientific sense is a theory that explains observations. A new science paradigm is one that better explains data – in this case climate data – than the old theory. The new theory says that climate change occurs as discrete jumps in the system. Climate is more like a kaleidoscope – shake it up and a new pattern emerges – than a control knob with a linear gain. This article reviews abrupt change in simple systems, in a 1-D climate model and in the climate system at multi-decadal timescales.

    This idea is the most modern – and powerful – in climate science and has profound implications for the evolution of climate this century and beyond.

    http://watertechbyrie.com/2014/06/23/the-unstable-math-of-michael-ghils-climate-sensitivity/comment-page-1/#comment-53

    There are more difficult ideas than agriculture influencing climate. It still does in a major way – and in fact provides an importing mechanism for both carbon dioxide mitigation and for improving agricultural productivity.

    e.g. http://judithcurry.com/2013/06/07/soil-carbon-permanent-pasture-as-an-approach-to-co2-sequestration/

    But the point is that the dissemination of simple ideas that are supportive of a paradigm is not a measure of the progress of complex ideas that challenge a paradigm.

  15. 15

    Steve Schneider went beyond Sagan’s observation by insisting thet “extraordinary evidence ” be subjected to extraordinary scrutiny,

    When Sagan introduced his 1983 ‘article ‘Nuclear War And Climatic Catastrophe’ with the words “Apocalyptic predictions require higher standards of evidence…” Steve and Strley Thompson responded in Foreign Affairs with “Nuclear Winter Reappraised.” questioning both the supposed sopistiaction of Sagan’s 1-D model and the extraordinary parameter assumptions that went into it.

    The consequences of the first collision of climate science and political advertising linger, as some climate deniers try to tack ‘catastrophic’ on to AGW, and some climate activists continue to indulge in existential threat inflation in the name of ‘framing’.

  16. 16

    #8–Excellent link, Hank. I’ve only ever tried to publish on music theory, and the process was fairly similar. I quit somewhere around step #6.

  17. 17
    Chris Colose says:

    Jai (#4)

    There’s no reason to expect that a volcanic eruption could initiate permanent ice sheet formation of the scale you’re suggesting. The slight changes in the methane/solar boundary conditions aren’t relevant here. The timescale of the aerosol forcing vs. ice sheet growth are just radically different.

    There’s been some recent literature on decadal timescale influence of volcanic eruptions, e.g., operating through sea ice/ocean feedbacks, but if there’s a signal on timescales much longer than the direct sulfate forcing it’s fairly small. I’m sure you can make a simple model kick in to a much longer lived “cold” and stable state (after feedbacks) with a big enough short-lived forcing, but more sophisticated GCMs (and the paleoclimate record) don’t do this under most circumstances.

    In any case, there’s likely been larger eruptions during the last millennium (e.g., Samalas- though there’s a lot of uncertainties in these reconstructions) and even farther back in time (when you start talking about Toba 74,000 yrs ago, etc). What’s more, aerosol size for big eruptions becomes important since particles larger than 1-2 microns start scattering less and work through the infrared part of the budget better, taking some of the bang out of the global cooling you’d otherwise expect.

  18. 18
    Jai Mitchell says:

    Steve @6

    Yes, Dalton Minimum, thanks working from memory here.

    The CO2 and CH4 values I stated are what Early Anthropogenic Emissions theory indicates would be the atmospheric concentrations in 1816 absent anthropogenic land-use changes.

    see: http://3.bp.blogspot.com/-jr0io-V-3rY/UshV3nNO0bI/AAAAAAAAAS4/iKLql3wewgU/s1600/ruddiman.png

  19. 19
    S. Molnar says:

    Well, gosh, I’m opposed to AGW, and I’m not even a scientist.

  20. 20
    Steve Fish says:

    Re- Comment by Mal Adapted — 13 Apr 2015 @ 1:56 PM, ~#8

    Mal Adapted, I disagree with your comment claiming that we “don’t know how to communicate.” I don’t think that there is any way that scientists could improve their communication skills that wouldn’t be negated by clever paid science denial. A financially well supported campaign consisting of aggressive comedians could probably laugh the likes of Watts and the Heartland Institute off the stage because there is so much rich humor available there, but in the US, about half of the population believes that the culturally biased opinions of their favored religious and political leaders trump scientific evidence and explain any discrepancies with government conspiracies. This problem is greatly exacerbated by many agencies whose purpose is obviously entertainment that claim that they are presenting news.

    Steve

  21. 21
    Oale says:

    (jokingly) The funny part of this absolutely correct theory of early anthropocene is that the influence of man on earths’ climate is stated stated to begin right at the beginning of monotheistic religions. So it could be stated ‘AGW is God’s work.’ Still the deniers deny. Of course I reserve the right to change my mind so I don’t have to blame the Hittites for it and reserve the right of religious freedom.

  22. 22
    Steve Fish says:

    Re- Comment by Barton Paul Levenson — 13 Apr 2015 @ 10:45 AM, ~#3

    So BPL, what did the editors tell you when you called them up to get more information?

    Steve

  23. 23
    Jai Mitchell says:

    Chris Colose @17

    According to David Archer, the northern hemisphere solar insolation point that allows the nucleation of ice sheets in North America occurs once the energy balance can support permanent snow cover. However, the condition for glaciation/deglaciation both exist simultaneously for some period of time as the milankovitch cycles operate on very long periods. Once this threshold is breached and CO2 and CH4 have decline below a critical balance point, a single ‘tipping point’ event such as a large eruption may provide the single decade of extra cooling that would allow for a significant, permanent snowcover to form over the upper latitudes. The resultant increase in summer albedo would produce a significant negative forcing factor that leads to the rapid climate plunge that we see in the volstok temperature record as re glaciation occurs. (please note here that we are only looking at the mid to late holocene here so Toba isn’t part of the analysis)

    After looking at the image I found in 18 above, it seems that the reglaciation threshold would have been passed sometime around 3000 BCE but I am sure that there is significant uncertainty about this point.

  24. 24

    That’s me that Hank Roberts is referring to in #8. My name is Paul Pukite and I am in no way, shape, or form a climate science insider. I have published in several other physics and engineering disciplines but harbor no illusions that I can easily get published in an earth sciences field such as climate science. The key word there is “easily”. That’s why I am in no hurry and continue to spend a few hours a week working on these “fruit fly” models of climate, as Isaac Held refers to them.

    Funny story is that I actually received a response to a climate science paper that I submitted explaining that it was ejected because one of the reviewers said it looked like one of those “AI generated” research papers.

    This is real life and stuff like that happens. If you think you are doing interesting and challenging work, you plow forward.

    So what Hank links to in regards to the “Abstract Noun” journal publishing process is par for the course.

  25. 25

    That’s me that Hank Roberts is referring to in #8. My name is Paul Pukite and I am in no way, shape, or form a climate science insider. I have published in several other physics and engineering disciplines but harbor no illusions that I can easily get published in an earth sciences field such as climate science. The key word there is “easily”. That’s why I am in no hurry and continue to spend a few hours a week working on these “fruit fly” models of climate, as Isaac Held refers to them.

    Funny story is that I actually received a response to a climate science paper that I submitted explaining that it was ejected because one of the reviewers said it looked like one of those “AI generated” research papers.

    This is real life and stuff like that happens. If you think you are doing interesting and challenging work, you plow forward.

    So what Hank links to in regards to the “Abstract Noun” journal publishing process is relatable to me and possibly par for the course.

  26. 26
    Rod B says:

    I meant introspection, not retrospective…

  27. 27
    Mark A. York says:

    Indeed. Barton thinks he has something new to add to the subject but lacks the credentials needed to even get in the door. It’s like not having an MFA but wanting to publish a literary novel with Simon and Schuster. Not gonna happen.

  28. 28
    Bill Ruddiman says:

    Comments and clarifications on #’s 5, 11, 17, 18, 23:

    At the orbital scale: The 240-245 ppm anthropogenic-free CO2 value we project for the late Holocene is 40-45% of the way from the typical interglacial 280-ppm extreme to the 190-ppb glacial extreme. Our 445-450 ppb CH4 estimate adds more negative radiative forcing to the orbital total. In addition, orbital obliquity has fallen about half-way toward its minimum value and the northern summer insolation response to precession more than that, so the combined orbital forcing during the key northern summer season is also about half-way toward the glacial extreme. Given that northern ice sheets have existed for 90% of the last 800,000 years, renewed glaciation in a modern anthropogenic-free world should not be surprising. GCM simulations by John Kutzbach, Steve Vavrus and others at Wisconsin using current orbital values and the proposed anthropogenic-free GHG estimates show 12-month snow cover (incipient or embryonic glaciation) in several areas at high northern latitudes.

    At shorter time scales: CO2 in Law Dome ice hit a 284-285 ppm peak from 1100 to 1200. This was likely due to deforestation, plausibly in eastern Europe (west-central Europe was already deforested), southernmost China (north-central China was already deforested), southern Asia, and in the growing civilizations in the Americas. The 7-10 ppm drop between 1525 and 1600 coincides with the 85-90% American mortality rate caused by diseases brought in by European contact, thereby allowing forests to reoccupy previously cultivated land and sequester carbon. As for other forcings, individual volcanic explosions caused coolings lasting a few years, with increased snow cover, but the global climate system would likely have returned to previous levels within a few years. Short-term solar influences have now been downgraded to small or inconsequential. Slow orbital forcing produced cooler summers at high northern latitudes, but temperature changes during northern winters and in both seasons elsewhere were more subtle and are harder to reconstruct.

  29. 29

    I have to claim that scientists are not speaking out enough – especially climate scientists. As indicated in a recent Yale poll (http://environment.yale.edu/poe/v2014) asking “Estimated % of adults who believe most scientists think global warming is happening, 2014”: — it’s less than 50%. Why are scientists perceived that way? Maybe because scientists speak out in areas that are not their expertise – and thus the burden should be more on climate scientists with respect to AGW anyway. The medical field hasn’t helped our effort for scientific credibility when one year caffeine is ok and the next not (same for salt, diets, fats, etc. – that confuse the public and lead to not trusting scientists. Many who claim to be scientists might have been trained in science and apply what they’ve learned in technical ways – but that doesn’t make them “scientists”. We’ve become a country of self-proclaimed experts at every topic in the world. The effort must go on. Anyone who has studies past climates and kept up with the research and discovery don’t need models to tell them where AGW is going to lead us. However, the modern climate scientists can tell us how we are getting there – and must use models to do so. Climate modeling, I’d argue is more accurate than weather modeling; I think most would agree – but explaining that to the public is difficult and leads to the distrust of climate models/modeling. We must continue using this page (realclimate.org and skepticalscience.com) to refute disinformation. Here in Denver, in the Ethics and Environmental Economics study group (http://denverclimatestudygroup.com/?page_id=683) on April 13 we reviewed George Marshall’s “psychological book”: “Why our brains are wired to ignore climate change and what to do about it” and I encourage all to read it and be informed of the challenges we face.

  30. 30
    Mal Adapted says:

    Steve Fish:

    Mal Adapted, I disagree with your comment claiming that we “don’t know how to communicate.”

    Heh. If you thought you were disagreeing with me, I definitely don’t know how to communicate 8^D!

  31. 31
    Aaron Lewis says:

    I find that if I make an interesting point, somebody will promptly write a paper on it. Why should I bother writing papers if I can get others to write them for me?

    From my point of view, it is not difficult to get papers published as long as I do not care who gets the credit.

    And, I would say that the greatest tool of the denial machine is pay walls around of the journals. Our county library no longer subscribes Science or Nature.

  32. 32
    sidd says:

    Prof. Ruddiman thank you for many stimulating papers and books. I did read “Earth Transformed” with enjoyment, but I must admit to missing “Plows, Plagues and Petroleum.”

    I seem to recall that you have previously pointed out the importance of enhanced peat sequestration in the Holocene to balance the isotopic budget, which led me to wonder: We see evidence today of enhanced peat breakdown, would this be visible in isotopic measurements ?

    sidd

  33. 33

    PB 27,

    No. You’re making the mistake the Republican Party keeps making–thinking that if only you made the message clear enough, people would agree with it. It’s not a messaging problem. The problem is on the other end. People could understand perfectly well what we’re saying and still reject it.

  34. 34
    Hank Roberts says:

    I would say that the greatest tool of the denial machine is pay walls around of the journals.

    Yep. Clear message: important people can afford to know about science.
    You don’t want to pay for it? You don’t matter.

    Wrong message, for this.

    http://io9.com/5842304/why-does-it-cost-20000-a-year-to-subscribe-to-a-science-journal

  35. 35
    Bill Ruddiman says:

    Clarifications regarding comments 5, 11, 17, 18, 23:

    At the orbital scale: The 240-245 ppm anthropogenic-free CO2 value projected for the late Holocene is 40-45% of the way from the typical interglacial 280-ppm extreme to the typical 190-ppb glacial extreme. Our 445-450 ppb CH4 estimate adds a little more negative radiative forcing to the orbital total compared to the observed GHG trends. In addition, orbital obliquity has now fallen about half-way toward its long-term minimum value and the northern summer insolation response to precession even more, so the combined orbital forcing during the key northern summer season is also about half-way toward the glacial extreme. Given that ice has been present on North America for 90% of the last 800,000 years, renewed glaciation in a modern anthropogenic-free world with reduced orbital forcing should not seem surprising. GCM simulations by John Kutzbach, Steve Vavrus and others at Wisconsin using current orbital values and the proposed anthropogenic-free GHG estimates show 12-month snow cover (indicating incipient or embryonic glaciation) in several areas at high northern latitudes.

    As for shorter time scales: CO2 in high-resolution Law Dome ice reached a peak of 284-285 ppm from 1100 to 1200. This maximum was likely due to deforestation, most plausibly in eastern Europe (west-central Europe had already been deforested), southernmost China (north-central China had already been deforested), southern and southeast Asia, and regions with growing populations in the Americas. The subsequent 7-10 ppm CO2 drop between 1525 and 1610 coincides with a mortality rate of 85-90% among early Americans due to diseases introduced by European contact. This near-total mortality allowed forests to reoccupy previously cultivated land and sequester carbon. So: anthropogenic CO2 emissions and sequestration played some role during the last 500 years, but so did volcanic explosions that caused short-term cooling and orbital forcing that gradually led to cooler summers at high northern latitudes.

  36. 36
    Steve Fish says:

    Re- Comment by Paul Belanger — 14 Apr 2015 @ 3:03 PM, ~#27

    Paul, I advise caution when describing medical claims in popular culture as science based because science isn’t the voice that makes the absolutist claims (e.g. caffeine OK or not). The problem here is with government bureaucrats, media outlets looking for more market share and, surprisingly, nutrition organizations. I am not saying that you don’t understand this, just that what you wrote implies this.

    The problem is that in large areas of research that have impact on the general public (e.g. health, evolution, climate), one or a small number of studies do not represent the totality of a scientific area that has many thousands of interlocking studies. As we have seen here at Real Climate regarding the climate sciences, individuals and organizations with cultural or political motivations will cherry pick one or a few studies that may appear to support their non-scientific view and use the media, which is mostly motivated by market share not accuracy, to push their agenda.

    In other words, it isn’t that climate science is so difficult to explain at all, it is that non-scientific opposition is effective with about half the population.

    Steve

  37. 37
    adelady says:

    Paul Belanger “I have to claim that scientists are not speaking out enough – especially climate scientists.”

    I don’t think that’s the issue at all. I – along with all my union friends who’d been frightfully proud of their monthly newsletters – were absolutely dismayed when we got some advice from a PR/marketing person. They told us that research shows that people don’t reliably recognise your name or message until they’ve seen or heard it an astonishing number of times. (I recall 23, but I’m not betting anything on that.)

    What they emphasised was that commercial products and services don’t have any opposition apart from brand name or details. There are no other people advertising on the basis of don’t brush your teeth or clean your house or care for your children. Even though they’re not advertising your product they’re supporting your message by reinforcing the message of cleanliness or child health.

    As soon as you’re faced with competition that undercuts or openly opposes your message, you need far more effort to get it across. And then you have to get people to take action on that message rather than just recognise or accept it.

    So it’s not just up to climate scientists to put out the message. It’s up to everyone else who endorses or agrees with it to find ways to repeat and reinforce it. Over and over and over again. Lather, rinse, repeat. You cannot expect people to hear something, understand it, and take its message seriously enough to take action on that basis, especially when that message is contradicted or overwhelmed half a dozen times a day by other messages.

    That’s not how people “work”.

  38. 38
    Tom says:

    Steve Fish says:
    13 Apr 2015 at 9:24 PM
    Re- Comment by Mal Adapted — 13 Apr 2015 @ 1:56 PM, ~#8

    A financially well supported campaign consisting of aggressive comedians could probably laugh the likes of Watts and the Heartland Institute off the stage because there is so much rich humor available there,
    Clip:

    I really wish the Onion accepted contributions. I think a good article might start with the headline “Republicans claim win in climate debate. Shift top politicians to problem of quantum gravity.”

    The denialist sphere may even believe that they have already made a major contribution to science. Niel deGrass Tyson is fond of saying that, “The good thing about science is that it’s true whether or not you believe in it.” But Skeptics might think they have gotten around this using Quantum Political Entanglement. In QPE if you entangle scientific facts with enough innuendo, misinformation, phony experts, and political inertia, you will not just change the public’s belief, but you may change the actual laws of physics as well. It sounds crazy at first, but what aspect of quantum theory doesn’t.

  39. 39
    Jim Prall says:

    Great to see Dr. Ruddiman chiming in at #35. On his point about depopulation of the Americas by epidemics after European contact, I can recommend a great pair of books by Charles C. Mann that give an in-depth overview of this issue, including recent research and some hotly debated interpretations.
    1491: New Revelations of the Americas Before Columbus
    1493: Uncovering the World that Columbus Created
    disclosure: I finished 1491 but haven’t started 1493 yet. I’m endorsing both on the premise that the author has proved himself in book 1 and I’m expecting no less from the follow-up.
    Links:
    http://www.amazon.ca/1491-Second-Revelations-Americas-Columbus/dp/1400032059/ref=sr_1_1?ie=UTF8&qid=1429228134&sr=8-1&keywords=1491
    http://www.amazon.ca/1493-Uncovering-World-Columbus-Created/dp/0307278247/ref=sr_1_2?ie=UTF8&qid=1429228134&sr=8-2&keywords=1491

  40. 40

    I think I lost the previous post. Please delete if it shows up.

    For the fun of it–if you can call it fun–I just did OLS analysis of the HadCrut4 temperature anomalies. A linear fit of anomaly A to year Y gives R^2 61%, F(1,162) 257, p too small to measure. A quadratic fit gives R^2 77%, F(2,161) 274, p too small to measure. SSE reduces from 10.31 to 6.062, for those who’d like to do a partial F-test. So not only is the temperature rising with time, it’s accelerating. Hang on to your hats! Looks like we’re going for a ride!

  41. 41
    Hank Roberts says:

    Tom, QPE isn’t a joke:

    … take neoliberal theorists like Hayek at their word when they state that the Market is the superior information processor par excellence. The theoretical impetus behind the rise of the natural science think tanks is the belief that science progresses when everyone can buy the type of science they like, dispensing with whatever the academic disciplines say is mainstream or discredited science.

    Mirowski, Philip, “The Rise of the Dedicated Natural Science Think Tank” (New York: Social Science Research Council, July 2008), op. cit.

  42. 42
    John Mashey says:

    Of course, the irony of certain people saying this wasn’t a challenge to the mainstream viewpoint (which was that most global climate change was natural until the I.R.) is:

    a) That was often used as base for meme “climate is always changing naturally, so not AGW.”

    b) And Bill’s work does not do away with internal variability … but it says we can show human effects going a long way back, on various time scales.

    Meanwhile, here’s your chance: watch his 2013 AGU Tyndall Lecture and ask questions here while he might still be watching.

  43. 43
    Dimis Poulos says:

    So they publish the nice ideas like yours. When I manage to publish MY paper on a journal I ‘ll tell you!

  44. 44
    Jai Mitchell says:

    Dr. Ruddiman,

    Thank you for your kind response.

  45. 45
    Mark A. York says:

    So, I’ve been involved in a debate about when the WAIS and Ross ice shelves will collapse. A famous nature writer I know hopes it’s, get this, “this year” so it will get government’s attention. When shown Stefan et al and others’ predictions, he called the 200 year timeline BS. “Decades,” he said. Maybe reiterate in a post? I mean we can’t have hoax deniers on one end and total doomsayers on the other when the truth is in between. Way in, in this case. I wish people were reasonable and went with facts but they go with the bandwagon of either stripe. It’s so discouraging.

  46. 46
    Scott Strough says:

    Bill Ruddiman,
    I was very intrigued by your research. Much more than this article itself. I happen to agree with the article BTW. There is no conspiracy here. However there are certain biases that are incredibly difficult to crack. Your paper, THE ANTHROPOGENIC GREENHOUSE ERA BEGAN THOUSANDS OF YEARS AGO, combined with diverse research from completely different sources like Retallack, Teague, Savory, Sait, and Sandom could actually be part of a paradigm changing new synthesis in climate science.

    The interesting thing to me is that these widely separate lines of investigation, from modern agricultural practices to ancient human impacts on the megafauna to paleosoils all are slowly converging on the idea that soils as part of a whole ecosystem have a much larger impact on ecosystem services than previously thought. Particularly the ecosystem services of climate control and the carbon cycle. Namely I hypothesize the AGW effects we are seeing now are actually primarily the result of multiple trophic cascades caused by the spread of mankind and then the rise of civilization. Further that fossil fuel emissions are a problem primarily due to the ecosystem service of carbon sequestration into the soils was already severely damaged, first by the megafaunal extinctions, and then by agriculture, both manmade. Most modern climate models measuring the carbon cycle seem to be measuring the highly degraded ecosystem function currently present worldwide and not factoring in the capability of a fully functioning biome, especially the grassland/savanna biomes. It’s easy to understand why. Hard to measure what has already been destroyed.

    These diverse lines of inquiry, including yours, are not completed into a fully developed synthesis as of yet, but I am convinced yours is the right track not only in better understanding the atmospheric CO2 levels, but also how to reverse them.

  47. 47
    vukcevic says:

    This is note to : Lihua Ma, Chinese Academy of Sciences
    Springer Link
    Science publication: Studia Geophysica et Geodaetica

    Regarding publication:
    Studia Geophysica et Geodaetica Date: 22 Feb 2015
    Possible influence of the 11-year solar cycle on length-of-day change

    First article demonstrating LOD-Sunspot Cycles link was published:
    Role of Natural Cycles in the Global Climate Change
    (pages 13 &14)
    https://hal.archives-ouvertes.fr/file/index/docid/728145/filename/GEO-SOLAR-oscillations.pdf
    Submitted on 4 Sep 2012 by M. Vukcevic, MSc– independent researcher

    And more recently
    Evidence of Length of Day (LOD) Bidecadal Variability Concurrent with the Solar Magnetic Cycles
    (version 2) Submitted on 29 Oct 2014
    https://hal.archives-ouvertes.fr/hal-01071375v2/document

  48. 48
    Tom says:

    Hank Roberts says:
    17 Apr 2015 at 10:32 AM
    Tom, QPE isn’t a joke:

    … take neoliberal theorists like Hayek at their word when they state that the Market is the superior information processor par excellence. The theoretical impetus behind the rise of the natural science think tanks is the belief that science progresses when everyone can buy the type of science they like, dispensing with whatever the academic disciplines say is mainstream or discredited science.

    Mirowski, Philip, “The Rise of the Dedicated Natural Science Think Tank” (New York: Social Science Research Council, July 2008), op. cit.

    – See more at: http://www.realclimate.org/index.php/archives/2015/04/a-scientific-debate/#comments

    Thanks. That was an interesting read, although a bit disconcerting.

  49. 49
    Lynn Vincentnathan says:

    As an anthropologist I thought the idea of early agriculture contributing to a bit of warming was interesting and perhaps held some water. There are 2 reasons — (1) early use of slash and burn in horticulture, plus most people were still hunters some 12,000 yrs ago, but they also used fire to herd game animals into bluffs, etc.

    Plus the fact that Smokey the Bear was not around to tell people not to play with fire. Homo erectus started using fire some 400,000 yrs ago, but the population then was quite tiny, so there wouldn’t have been hardly any impact until the population started booming with agriculture.

    (2) The other reason for believing that theory is — has anyone seen the global climate over the past millions of years? The Holocene looks warm and relatively very stable. Looks like something humans may have cooked up without realizing it — a warm and stable climate pretty much right for agriculture and the rise of civilization and the exponential rise in population….and in intensive agriculture, replacing extensive slash and burn.

    And I didn’t even see the actual article or data — it just made sense to me.

    Now what about that theory that early hunters killing off mega-fauna, thereby reducing their methane-emitting poop & decay, putting us into an ice age? Can’t remember where I read that, but who knows, it also makes some sense.

  50. 50
    Rob Ellison says:

    According to the authors, the massive expansion of energy systems, mainly carried out in the rapidly urbanizing global South, is the only robust, coherent, and ethical response to the global challenges we face, climate change among them. The time has come to embrace a high-energy planet, they say.

    “Climate change can’t be solved on the backs of the world’s poorest people,” said Daniel Sarewitz, coauthor and director of ASU’s Consortium for Science, Policy, and Outcomes. “The key to solving for both climate and poverty is helping nations build innovative energy systems that can deliver cheap, clean, and reliable power.”

    http://thebreakthrough.org/index.php/programs/energy-and-climate/our-high-energy-planet

    >Many of the same studies indicate that liberals and conservatives respond to fear-based appeals about climate change differently. Efforts, for example, to link current natural disasters to climate change motivate liberals and environmentalists, but alienate moderates and conservatives.

    On a positive note, many studies show that framing climate solutions around technological and economic progress and solutions increases belief in global warming…

    ‘In the first study, climate change deniers (N = 155) intended to act more pro-environmentally when they thought climate change action would create a society where people are more considerate and caring, and where there is greater economic/technological development. The second study (N = 347) replicated this experimentally, showing that framing climate change action as increasing consideration for others, or improving economic/technological development, led to greater pro-environmental action intentions than a frame emphasizing avoiding the risks of climate change.

    http://thebreakthrough.org/index.php/programs/energy-and-climate/the-psychology-of-climate-change

    Which is the side of the angels?

    Most sceptics don’t seem to doubt that greenhouse gases are climatologically active – although beyond that there is considerable room for dissension. Indeed the joke around the John Cook 97% paper was that most sceptics were in the yes camp – based on the definitions used. There are some weird theories out there – but this is hardly restricted to the right. This is a topic in which social narrative has taken on monstrous dimensions.

    Moderates might frame it as an N2N strategy – natural gas to nuclear – and as such it is easily sellable to sceptics. That solves some 26% of the greenhouse gas emissions issue – and perhaps a little of the aerosols. Do it wrong and all of the problems humanity faces this century are compounded.


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