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Plimer’s homework assignment

Filed under: — gavin @ 24 August 2009

Some of you may be aware of George Monbiot’s so-far-unsuccessful attempt to pin down Ian Plimer on his ridiculous compendium of non-science. In response to Monbiot’s request for explanation and sources for some of Plimer’s more bizarre claims, Plimer has responded with a homework assignment that is clearly beyond even his (claimed) prowess. This is quite transparently a device to avoid dealing with Monbiot’s questions and is designed to lead to an argument along the lines of “Monbiot can’t answer these questions and so knows nothing about the science (and by the way, please don’t notice that I can’t cite any sources for my nonsense or even acknowledge that I can’t answer these questions either)”. (Chris Colose and Greenfyre have made similar points). It’s also worth pointing out as Andrew Dodds has done that each question is actually referencing a very well known contrarian and oft-debunked argument, but dressed up in pseudo-scientific complexity.

However, as a service both to Plimer and Monbiot (as well as anyone else interested), we give a quick scorecard on the relevance, actual scientific content (whether the questions can actually be answered) and sources for discussion for each of the, to be charitable, ‘odd’ questions. For relevance, we grade each question on a scale from 0 to 5, 0 being irrelevant to the issue of detection and attribution of 20th Century climate change, 5 being extremely relevant. For scientific content, we rate the reasonableness of the question posed (i.e. does it make any sense at all), from A to F (A being a very well posed question, F making no sense). For sources, we generally point to a paper or discussion that addresses the real issue.

  1. From the distribution of the vines, olives, citrus and grain crops in Europe, UK and Greenland, calculate the temperature in the Roman and Medieval Warmings and the required atmospheric CO2 content at sea level to drive such warmings. What are the errors in your calculation? Reconcile your calculations with at least five atmospheric CO2 proxies. Show all calculations and justify all assumptions.
    • Relevance: 0 – poor. Basic logical fallacy. The existence of prior warm periods that may have been caused by different effects (such as solar changes, orbital variation, continental configuration etc.) does not imply that the human-caused increase in CO2 is not causing warming now.
    • Scientific Content: D – phenology (the distribution and timing of species) can potentially be useful for tracking climate changes, but it is just one of many different types of proxy information available, and has its own regional, temporal, and seasonal limitations. Even more problematic, it is well known that the patterns of surface temperature variability during the “MWP” – more accurately, the Medieval Climate Anomaly (MCA) – and LIA periods were spatially quite heterogeneous, and a record at one or two locations generally tells us very little if anything about global patterns. Even a cursory examination of the relevant recent literature (for instance, Osborn and Briffa, 2006) reveals that the pattern of warmth during the Medieval era was far regional in nature, and does not approach the truly global scale of warmth evident in recent decades.
    • Sources: Greater extent of vineyards today in England than in medieval times. Ice core records. Incoherence of the Medieval warm period.
  2. Tabulate the CO2 exhalation rates over the last 15,000 years from (i) terrestrial and submarine volcanism (including maars, gas vents, geysers and springs) and calc-silicate mineral formation, and (ii) CH4 oxidation to CO2 derived from CH4 exhalation by terrestrial and submarine volcanism, natural hydrocarbon leakage from sediments and sedimentary rocks, methane hydrates, soils, microbiological decay of plant material, arthropods, ruminants and terrestrial methanogenic bacteria to a depth of 4 km. From these data, what is the C12, C13 and C14 content of atmospheric CO2 each thousand years over the last 15,000 years and what are the resultant atmospheric CO2 residence times? All assumptions need to be documented and justified.
    • Relevance: 0 – pure misdirection.
    • Scientific Content: F – We know what CO2 and CH4 levels have been over the last 15,000 years and they oscillated within about 10 ppmv (CO2) and 100 ppbv (CH4) of their Holocene values since the start of the current era – until the industrial period (around 1750) since when CO2 has increased by 35%, and methane concentrations have more than doubled. In each case the values being measured today are way higher than anything measured in 800,000 years of ice core records, and likely higher than anything since the Pliocene (~3 million years ago). The idea that bacterial methane production at 4km in the Earth’s crust has anything to with this is laughable.
    • Sources: IPCC FAQ is all that is required. Do volcanoes produce more CO2 than human activity? Not even close.
  3. From first principles, calculate the effects on atmospheric temperature at sea level by changes in cloudiness of 0.5%, 1% and 2% at 0%, 20%, 40%, 60% and 80% humidity. What changes in cloudiness would have been necessary to drive the Roman Warming, Dark Ages, Medieval Warming and Little Ice Age? Show all calculations and justify all assumptions.
    • Relevance: 3 – clouds certainly have an effect on climate and understanding their variability is the subject of much research.
    • Scientific Content: F – The question makes no sense. Clouds at 0% humidity? Is humidity supposed to be globally uniform? And where should these cloud changes occur? The change for low-level clouds will be of the opposite sign to changes in high level clouds, and changes in the Arctic will give different answers than changes in the tropics. It should go without saying that Plimer is mistakenly assuming that he has accurate information for global temperatures over 2000 years.
    • Sources: Cloud Feedbacks in the Climate System.
  4. Calculate the changes in atmospheric C12 and C13 content of CO2 and CH4 from crack-seal deformation. What is the influence of this source of gases on atmospheric CO2 residence time since 1850? Validate assumptions and show all calculations.
    • Relevance: 0 – completely irrelevant.
    • Scientific Content: F – for those that don’t know ‘crack-seal deformation’ is a geologic process that causes the veins of crystals/minerals etc. in many rock types. (see here). Its relevance to atmospheric concentrations and isotopic composition is absolutely zero. It has no influence on atmospheric residence time – whether since 1850 or at any time in the past.
    • Sources Discussions of the actual carbon cycle and the real influences upon it.
  5. From CO2 proxies, carbonate rock and mineral volumes and stable isotopes, calculate the CO2 forcing of temperature in the Huronian, Neoproterozoic, Ordovician, Permo-Carboniferous and Jurassic ice ages. Why is the “faint Sun paradox” inapplicable to the Phanerozoic ice ages in the light of your calculations? All assumptions must be validated and calculations and sources of information must be shown.
    • Relevance: 0 – (again). The acknowledged climate changes in the past caused by natural events in no way implies that human effects are negligible today. Does the existence of forest fires caused by lightning imply that arson can never happen?
    • Scientific Content: C – There is a lot of interesting science related to deep time, but any discussion of such changes must be prefaced with the acknowledgment that our knowledge of greenhouse gases, temperatures or any other potential forcing or response is very limited compared to what we know about climate today or even in the last ice age. Given that we don’t know precisely what CO2 levels were (let alone CH4, N2O, ozone, aerosols, ice sheet configurations, vegetation distribution etc.), the attributions of climate change at this distance is speculative at best.
    • Sources: The faint young sun paradox.
  6. From ocean current velocity, palaeotemperature and atmosphere measurements of ice cores and stable and radiogenic isotopes of seawater, atmospheric CO2 and fluid inclusions in ice and using atmospheric CO2 residence times of 4, 12, 50 and 400 years, numerically demonstrate that the modern increase in atmospheric CO2 could not derive from the Medieval Warming.
    • Relevance:1 – There are amplifying feedbacks between climate and CO2 – which are most evident in the long ice cores from Antarctica, but this argument is trivial to dismiss without any recourse to ocean current velocities etc.
    • Scientific Content:D – You can calculate the change in CO2 per deg C global warming over long (multi-centennial) timescales from the ice age data – it’s roughly 100ppmv/5ºC = 20 ppmv/ºC. The increase in atmospheric CO2 in the last 200 years is now about 110ppmv, implying that any natural driver would have need to have been more than 5ºC natural warming in recent centuries. This would have been noticed by someone.
    • Sources: None required.
  7. Calculate the changes in the atmospheric transmissivity of radiant energy over the last 2,000 years derived from a variable ingress of stellar, meteoritic and cometary dust, terrestrial dust, terrestrial volcanic aerosols and industrial aerosols. How can your calculations show whether atmospheric temperature changes are related to aerosols? All assumptions must be justified and calculations and sources of information must be shown.
    • Relevance: 4 – aerosols are an important climate forcing, and their history through time (even in the 20th Century) are quite uncertain.
    • Scientific Content: C – Calculating the impacts of aerosols is quite hard, first because we don’t have great records for their distribution through time and space, and secondly there are uncertainties in how the mix with each other and how they interact with clouds. Forcing estimates for the human-caused changes in aerosols over the 20th Century therefore have quite large uncertainties associated with them and are a principle reason why attempts to constrain climate sensitivity from the recent record along have not been very successful. Volcanic effects are however quite well characterised, and actually provide one of the many lines of evidence for why GCM simulations are reasonable since they get the right magnitude and character of the volcanic effects on climate. However, there is no evidence whatsoever for large changes in interstellar dust changes in recent millennia and trying to pin recent warming on that is really grasping at straws.
    • Sources: Climate sensitivity and aerosol forcings.
  8. Calculate 10 Ma time flitches using W/R ratios of 10, 100 and 500 for the heat addition to the oceans, oceanic pH changes and CO2 additions to bottom waters by alteration of sea floor rocks to greenschist and amphibolite facies assemblages, the cooling of new submarine volcanic rocks (including MORBs) and the heat, CO2 and CH4 additions from springs and gas vents since the opening of the Atlantic Ocean. From your calculations, relate the heat balance to global climate over these 10 Ma flitches. What are the errors in your calculations? Show all calculations and discuss the validity of any assumptions made.
    • Relevance: 0 – again more misdirection. The throwing around of irrelevant geologic terms and undefined jargon is simply done in order to appear more knowledgeable than your interlocutor. The argument appears to that climate is changing due to tectonically slow changes the direct heat input from ocean sea floor spreading. This is absurd.
    • Scientific Content: F.
    • Sources: Definition of ‘flitch’.
  9. Calculate the rate of isostatic sinking of the Pacific Ocean floor resulting from post LGM loading by water, the rate of compensatory land level rise, the rate of gravitationally-induced sea level rise and sea level changes from morphological changes to the ocean floor. Numerically reconcile your answer with the post LGM sea level rise, oceanic thermal expansion and coral atoll drilling in the South Pacific Ocean. What are the relative proportions of sea level change derived from your calculations?
    • Relevance: 2 – pretty much irrelevant.
    • Scientific Content: C – isostatic issues in sea level are important on long time scales, and there is still an effect today from the deglaciation 15000 years ago. It contributes a decrease of about 0.3 mm/yr to the global sea level rise, compared to 3 mm/yr total (i.e. about 10%). If the idea was to imply that current sea level rise is simply the response to the deglaciation, then it was completely misleading.
    • Sources: Reconciliation of the sea level rise, thermal expansion and ice melt.
  10. From atmospheric CO2 measurements, stable isotopes, radiogenic Kr and hemispheric transport of volcanic aerosols, calculate the rate of mixing of CO2 between the hemispheres of planet Earth and reconcile this mixing with CO2 solubility, CO2 chemical kinetic data, CO2 stable and cosmogenic isotopes, the natural sequestration rates of CO2 from the atmosphere into plankton, oceans, carbonate sediments and cements, hydrothermal alteration, soils, bacteria and plants for each continent and ocean. All assumptions must be justified and calculations and sources of information must be shown. Calculations may need to be corrected for differences in 12CO2, 13CO2 and 14CO2 kinetic adsorption and/or molecular variations in oceanic dissolution rates.
    • Relevance: 5 – the carbon cycle is actually a key issue.
    • Scientific Content: A – understanding the carbon cycle given multiple constraints on the carbon fluxes (including some of the issues raised in the question) is important in showing that the ~35% rise in CO2 since ~1750 is in fact anthropogenic. This has been shown numerous times to be consistent with the known human emissions, increases in oceans and terrestrial carbon, the decrease in 14C content of the atmosphere, the decrease in 13C content in the atmosphere, the decrease in O2 in the atmosphere.
    • Sources: Read the FAQ.
  11. Calculate from first principles the variability of climate, the warming and cooling rates and global sea level changes from the Bölling to the present and compare and contrast the variability, maximum warming and maximum sea level change rates over this time period to that from 1850 to the present. Using your calculations, how can natural and human-induced changes be differentiated? All assumptions must be justified and calculations and sources of information must be shown.
    • Relevance: 4 – detection and attribution of climate change is an important issue.
    • Scientific Content: B – First principles calculations of climate variability are most closely approximated by GCMs and multiple modelling groups have done various Holocene simulations. Attribution of any climate changes requires model simulations with and without each particular forcing and for the Holocene, this involves changes in the orbit, greenhouse gases, solar, meltwater regimes, ice sheet change, aerosols etc. and a comparison of the signature of the responses with patterns observed in the real world. However, comparable data to 20th Century sea levels or temperature changes are not available going back to the beginning of the Holocene.
    • Sources: Attribution of mid-Holocene hydrologic changes to orbital forcing. Attribution of patterns of cooling at 8.2 kya to drainage of Lake Agassiz. Attribution of pre-industrial variability over the last millennia to solar and volcanic forcing (IPCC Ch8, p680+).
  12. Calculate the volume of particulate and sulphurous aerosols and CO2 and CH4 coeval with the last three major mass extinctions of life. Use the figures derived from these calculations to numerically demonstrate the effects of terrestrial, deep submarine, hot spot and mid ocean ridge volcanism on planktonic and terrestrial life on Earth. What are the errors in your calculations?
    • Relevance: 1 – irrelevant. Has nothing to do with current causes of species extinction nor sources of CO2.
    • Scientific Content: D – insufficient data exist to infer atmospheric composition, nor the sources of any hypothesised fluxes. We think that it is likely that mass extinctions are probably bad for “planktonic and terrestrial life on Earth” with very little error.
    • Sources: This is a good intro to the P/T extinction event which is fascinating even if mostly irrelevant to today.
  13. From the annual average burning of hydrocarbons, lignite, bituminous coal and natural and coal gas, smelting, production of cement, cropping, irrigation and deforestation, use the 25µm, 7µm and 2.5µm wavelengths to calculate the effect that gaseous, liquid and solid H2O have on atmospheric temperature at sea level and at 5 km altitude at latitudes of 20º, 40º, 60º and 80ºS. How does the effect of H2O compare with the effect of CO2 derived from the same sources? All assumptions must be justified and calculations and sources of information must be shown.
    • Relevance: 3 – radiative transfer is a key issue.
    • Scientific Content: F – the question as it stands makes no sense. How can using fossil fuel emissions of CO2 allow you to calculate the impact of total H2O? And why only three wavelengths? You would need the whole atmosphere distribution of water (in all three phases and which doesn’t exist outside a model) in order to calculate the radiative fluxes, and a full GCM to calculate all the other fluxes that influence the temperature. If Plimer is actually alluding to the impact of the direct injection of water vapour into the atmosphere from the combustion of hydrocarbons, then this makes even less sense since the perturbation time for water vapour is measured in days (rather than decades to centuries for CO2) and the relative importance of anthropogenic fluxes is much much less.
    • Sources: Importance of water vapour and clouds compared to CO2 for the total greenhouse effect (roughly, 50%, 25% and 20% once overlaps are apportioned). Complete irrelevance of anthropogenic addition of H2O. Calculation of radiative forcing for anthropogenic CO2.

In summary, the relevance of these questions is extremely low, and even when the basic question deals with an issue that is relevant, the question itself is usually nonsensical and presupposes many assumptions that are certainly not a given (at least in the real world). In fact, for the couple of cases where the scientific content is high, the answer is in contradiction to Plimer’s unstated assumptions. The most obvious use of these questions to support a ‘we don’t know everything, so we must know nothing’ type of argument, which is a classic contrarian trope, and one that is easily dealt with.

These questions have as much to do with a debate on human caused climate change as tribbles have to do with astrobiology. Both are troubling, but for very different reasons.

285 Responses to “Plimer’s homework assignment”

  1. 1
    Juliette says:

    I often read your blog but never comment, but just this once let me say it: you are AWESOME. Reading the questions on Monbiot’s blog last week, the first thing that came to my mind was “I wonder what the realclimate dudes would say about this?”
    Keep it up, we need you around.

  2. 2
    pete best says:

    Excellent work there RC. I did mention that the climate scientists should take a look at this over at the Guardian UK newspaper webiste where the article was published. I thought it was all nonsense but some if it has some relevance it would seem.

    The facts remain that the deniers will always find an angle to print something but only in the popular press.

  3. 3
    Steve Missal says:

    If these fellows (Plimer et al) actually worked as hard at actually looking at the reality of the data as they do in misrepresenting it, we’d have a remarkable paradigm shift in attitudes…or, it seems much more likely, they’re deliberately misleading the layman, which is very troubling. Question: why would you pour gasoline on a fire in your own living room? Answer (maybe): to collect the insurance. But, where is the payoff here for the Plimers of the world?

  4. 4

    Thanks for this detailed debunking. It’s very irritating see an experienced climatologist have to expend scarce resources to answer such drivel. The denialists can make stuff up off the cuff, and because of the reach of the circulation of their ideas, people like Gavin take time to respond.

  5. 5
    Steve Fish says:

    I had seen the questions previously, and I second what Juliette (#1) said. Thanks, again!


  6. 6
    Bob Ward says:

    Good work. Plimer’s attempts to mislead again begs the question about why so many geologists seem to be involved in collective denial of the findings of climate research – it’s as if they feel that their profession has been snubbed and they all have a chip on their shoulder about it. And I say this as somebody with a degree in geology. The most puzzling aspect is that they get the geology wrong (as the questions above show) as well as the atmospheric physics, oceanography, etc.

    [Response: This has come up before, and it’s very hard to make such generalisations. There are plenty of paleo people and geologists who understand this stuff just fine. Plimer is wrong because he’s wrong, he’s not wrong because he’s a geologist. (I realise this wasn’t the argument you were making but I’m emphasizing this point to avoid a stream of angry geologist responses!). – gavin]

  7. 7

    Superb analysis and fine presentation. A+

  8. 8
    tamino says:

    Terrific post! You guys rule.

    There are TWO main reasons Plimer submitted his nonsensical “questions.” One is, as you suggest, a combination of distraction and to make himself look so much smarter than Monbiot.

    The other, which I believe is the main reason, is: to avoid answering Monbiot’s questions. Perhaps my favorite is Monbiot’s question #2 about Plimer’s book:

    2. Figure 3 (page 25) is a graph purporting to show that most of the warming in the 20th Century took place before 1945, and was followed by a period of sharp cooling. You cite no source for it, but it closely resembles the global temperature graph in the first edition of Martin Durkin’s film The Great Global Warming Swindle. Durkin later changed the graph after it was shown to have been distorted by extending the timeline.

    In your book it remains unchanged.

    Tim Lambert has reproduced the graph here.

    a. What is the source for the graph you used?

    b. Where was it first published?

    c. Whose figures does it use?

    d. How do you explain the alteration of both the curves and the timeline?

    My guess: Plimer will never answer Monbiot’s questions, because the answers reveal him to be a fraud.

  9. 9
    Bob says:

    This whole thing would be funny, if it weren’t so serious, but I must admit… I care far less about things that are as laughably silly as this homework assignment, than about Lindzen’s recent paper on ERBE and positive versus negative feedback effects. I’ve been waiting oh-so-impatiently for an expert’s take on it, with nothing immediately forthcoming. I am assuming that this is because it involves real, involved science, and he is not an amateur or untalented scientist, so the review and critique process is more complex.

    My thought is that many people are at work looking at his paper, particularly the owners of the various “flawed” models, trying to find if there are any flaws in his logic, and no one wants to speak up until hard, cold logic can be properly and thoroughly applied to his observations.

    With that said, I must admit that while a small part of me wants to see him proved wrong so that the argument can be taken out of the anti-AGW arsenal, the bigger part of me wants him to be right. No matter how many “I told you so” comments I might have to listen to, I’d much rather discover that the earth has been keeping a secret super negative feedback mechanism in it’s hip pocket, and pulled it out to save us from ourselves when things were starting to look dire (sort of like Indiana Jones unexpectedly and abruptly shooting the Arab with the big sword in the first movie).

    But I also feel like the whole “unexpected negative feedback” thing would be just too good to be true.

    So… how long do you think we’ll have to wait for a good, solid, scientific appraisal of his report?

    [Response: Good point. As you recognise, Lindzen’s papers (unlike some of his more public comments) are not obviously screwy and therefore demand a bit more attention and work to examine. The one thing that seems odd here is the use of AMIP model runs, as opposed to CMIP simulations. (The difference is whether the ocean conditions are taken from observations (AMIP) or calculated independently (CMIP)). Both sets of runs are freely available from the same source and so access is not the reason why one was chosen over the other). The projections into the future and all statements about climate sensitivity are made with the CMIP models, not the AMIP ones (obviously since we have no observations from the future). Additionally, AMIP runs are known to have very counter-intuitive behaviour when it comes to surface energy fluxes (for instance, an oceanic warm anomaly caused by atmospheric anomalies in the real world is associated with an anomalous downward flux of heat – however in an AMIP run, the flux anomaly is upwards (completely opposite)). AMIP runs are useful, but it may be that Lindzen’s analysis is one of those things that is particularly sensitive to that. Maybe not, but someone has to look and see and that takes time. – gavin]

  10. 10
    Aaron Lewis says:

    RC is ever so much more polite, courteous, and tolerant than my college science professors.

  11. 11
    Harry Applin says:

    Why is it that the “deniers” always want someone to prove the existence of climate change when their only answer is that it is naturally occurring cycle.
    They always point to the little ice age as some holy grail for climate deniers but ignore all the evidence as to a major eruption impacting the atmosphere. They also like to point to the “natural” wobble of the earth but always leave out that large shifts of mass (ice to water and back) relate to the “wobble”.
    Would someone just stamp “idiot” on Ian Plimer forehead so we can move forward with more important things?

  12. 12
    Lin says:

    So I can only wonder … this guy Plimer teaches undergrad courses? What are his tests like?!?!?

  13. 13
    Lynn Vincentnathan says:

    Even a person of very low climate science abilities, such as myself, can answer some of the assumptions in at least some of those questions. Here might be my response: “Oh, really, there were warm periods caused by other factors, such as orbit or volcanism or clouds? That’s really bad news. It means those factors could start kicking in again and increase the anthropogenic global warming caused by our greenhouse gas emissions even further, maybe even to total cataclysm. That means, of course, we need to a least double our cuts in greenhouse gas emissions to offset these other factors over which we have no control, which, who knows (I suppose the scientists know), might start kicking in at any time. So let’s hop to it. Reduce, reduce, reduce, drastically reduce.”

  14. 14
    Rattus Norvegicus says:

    These questions read like a final exam written by a particularly cruel college professor who does not want anyone in class to pass the exam.

  15. 15
    CM says:

    I sure won’t complain that scientists have to spend their time on such things — I think I’ll learn a lot from this tour de force that I would never have come across otherwise. Really nice work.

  16. 16
    Christopher Hogan says:

    Truly outstanding. You are both an excellent writer and a person of great patience, to have waded through all that.

    I’d like to use this comment to point to an interesting but essentially off-topic image of US warming.

    Most US gardeners are familiar with the USDA hardiness zone map. The current (1990) USDA hardiness zone map uses minimum temperatures from 1974 to 1986. The scheduled 2005 update of the map was delayed, and rumor has it that the the delay was due to the USDA’s unwillingness to show how much the US had warmed since the last map. The USDA now plans to release an updated map, but this time, using the last 30 years of data. As the map reflects temperature minimums, that use of 30 years rather than shorter period used for the past two versions will hide the warming. The US Arbor Day foundation has recalculated the USDA hardiness zone map using the 1990 methods and the most recent available data. That is, the Arbor Day Foundation map is the modern analog of the 1990 USDA map. The resulting graphic of the change in the hardiness zones is startling. It’s particularly relevant because this map is a tool that almost all gardeners use. You’ll see it on the back of, well, basically any pack of seeds you buy.

    Anyway, I thought this might be a nice way to connect with the average American on the issue of climate change. It was also interesting to see how much the minimum recorded wintertime temperatures had changed. I think I understand that they ought to be more sensitive than the average. Even acknowledging that short term changes can be misleading indicators of trend, the fact is that the minima did change that much. Whether or not the new map will be a reliable guide for the next 15 years is unknown. But that there were very large changes in wintertime minima is a fact, nicely illustrated on the link above.

  17. 17
    David Erickson says:

    Gavin, thanks for once again being the voice of reason in the skeptic wilderness. As another poster noted schlock jobs such as this Plimer nonsense that show up on blogs are mostly light and no heat, and it’s a shame for someone like you to have to spend any time at all on this type of thing. Of greater concern is journaled work such as Lindzen’s and the yet to be published but oh so loudly heralded work of the U of Rochester physics department. According to their pre-print press release, this paper is about to be published in Physics Letters A. It “debunks” the theory of ocean warming, and that there is long term accumulating heat storage in the pipeline of the ocean. They claim that ocean heat flux has reversed several times in recent history, and that the direction of the heat flux of the ocean is unrelated to atmospheric CO2 levels. This is apparently a hard core scientific work by physicists and needs a response from the climate science community. I know you and your cohorts are not anxious to do this type of thing, but perhaps a response in RC is warranted. Whack-a-mole anyone?

  18. 18
    GFW says:

    Heh, “definition of ‘flitch'”. Anybody have any clue what Plimer meant that word to mean in context? I’m thinking “slice”.

  19. 19
    Jim Eager says:

    Chris Hogan (16), phenologic evidence, although often wrongly dismissed as merely anecdotal, provides some of the most compelling and long term evidence of the current warming and subsequent change in climate. European grape harvest records extend back long before actual temperature records, as do Japanese records of the blooming of cherrie blossoms. Environment Canada is also currently revising it’s hardiness zone maps by inviting citizen input, asking what plant species people are able to grow where they live and noting the expansion of ranges.

    One example: this summer a biologist I know stayed with a farmer who grows corn on St. George’s Bay on the southwest coast of Nerwfoundland along the Gulf of St. Lawrence. My friend was impressed with the very fact that the farmer could grow a commercially viable corn crop, much less the impressive extent of his plantings. The farmer related his experiments in growing species that had been impossible as little as 10 years ago, including several species of hardwoods and fruit trees, including maples, oaks and hardy kiwis. Anyone who has ever visited the southwest coast of Newfoundland will grasp the significance of this. The farmer was acutely aware that the climate has warmed considerably.

  20. 20
    Marion Delgado says:


    and the editable transcluded homework part, the main purpose, is

    I did it a week or 2 ago after I’d emailed Monbiot.

  21. 21
    Chris Colose says:

    Re #9, Bob

    I wasn’t quite sure why Lindzen’s model-observation comparison differed so much from the comparison by Wong et al 2006 so I’m glad gavin had some insight into the model aspect, which I’m not very good at going through myself. I’ve corresponded very briefly with some of the guys at Langley about this paper (as well as some of his other internet postings on feedback which didn’t use the Edition3 data discussed here ). He uses Edition3 in the new paper but it doesn’t appear to have applied the rev1 correction, which is to reduce the absolute magnitude of OLR and increase the absolute magnitude of SWR relative to Edition3 (but doesn’t influence the net). Hopefully other people will have further insight but I can’t imagine this paper is particularly robust given the large number of papers and paleoclimatic constraints on sensitivity.

  22. 22

    What Bob Ward (#6) said, only substitute meteorologists for geologists.

  23. 23
    Jeff says:

    Out of amusement, I typed in time flitches, surrounded by quotes, in a search engine. Not surprisingly, there were only six entries, five of which were related to Plimer.

  24. 24

    Did you notice that Plimer thinks the “Dark Ages” have something to do with climate? Someone should tell him the Dark Ages weren’t literally dark. It was a reference to the state of education and communication after the collapse of the western Roman Empire.

  25. 25
    Marion Delgado says:


    It’s transcluded into another page:

    It includes the history of the page

  26. 26
    Marion Delgado says:

    I can’t comment. It gives a server error, then says duplicate received, then when I reload the comments, it’s not there.

  27. 27
    David B. Benson says:

    Gavin — Well done!

  28. 28
    Deep Climate says:

    Getting back to Monbiot’s questions for Plimer, here is some discussion of Plimer’s claim that the 1934 was the “warmest year” on record (Monbiot’s question 4), as well as Plimer’s other claims about the recent temperature record. The claim about 1934 intrigued me as the National Post’s Lorne Gunter has made the same claim three separate times (and the Post still refuses to correct it and a legion of other errors).

    As Tim Lambert noted back in April, Australian Broadcasting Corporation’s Tony Jones effectively demolished Plimer’s distortions in a live interview. So what does ABC do? They give Plimer a propaganda platform (in the online “Unleashed” series) and refuse to allow rebuttal or correction.

    The questions for Plimer are all very well, and his refusal to answer them is, of course, very telling. But it’s also time to ask hard questions of the media outlets that disseminate this garbage. The continued refusal of Australian ABC, FoxNews and the National Post to uphold even a minimum of ethical journalistic standards is shameful.

    To be sure, much or even most of the mainstrean media, gives little credence to the contrarians. But, with very few exceptions, more responsible media outlets, like the New York Times or NBC, still do very little to expose the various pernicious disinformation efforts at all.

  29. 29
    David Horton says:

    If you haven’t seen it, one of the most recent, and extensive pieces from Plimer is here and could be read in conjunction with the Monbiot questions to understand the thinking behind them. A chillingly typical sentence is “A simple question does not get asked: what part of warming and cooling since 1850 is natural?” Impossible to understand how anyone could make such a statement seriously, let alone someone who has become a major figure in the debate. Much of the article has been dissected by Tamino and Enting, and there are god responses in the thread that follows the article. But something I haven’t seen commented on, which jumped out at me is “Climate chestnuts about polar ice are commonly raised. What is not raised is that ice is dynamic, it advances and retreats, while the Arctic is warming the Antarctic is cooling and vice versa and if ice did not retreat, then the planet would be covered in ice. ” Again, it is hard to imagine anyone purporting to be a serious commentator writing such a thing. I have red it several times, feeling my mind descending into a vortex of madness each time. I can only conclude that Plimer believes that there is only so much ice that can be present at one time on the planet, and if you lose some in the Arctic, then, like breathing out and breathing in, you gain some in Antarctica, and vice versa. As an example of the level of understanding of climate science among denialists it is hard to beat this one.

  30. 30
    Miguelito says:

    Re. #6.

    That’s easy. Coal and petroleum geologists often identify with their industry and their industry’s denialist bents. Whether it’s ideology or financial.

    And I say that as a petroleum geologist.

    Try cruising through the Canadian Society of Petroleum Geologists monthly newsletter (the Reservoir) of 2009 for Dr. Hutton’s denialist climate-change articles and its hodgepodge of the normal, debunked claims.

  31. 31
    William Hyde says:

    With regard to question #1, it is important to remember that agricultural practices are a function of technology as well as of climate. For example, in the 1830s all the milk drunk in the city of New York was locally produced (called “town milk” it was a definite health hazard as the cows were not very healthy). Twenty years later, none of it was. Climate change? No, the railroad. Previously it had been impossible to move milk by land more than a few miles before it spoiled.

    It cost far more in terms of cash and risk to ship wine from France to England in the middle ages. Thus it would make economic sense to grow grapes in otherwise marginal areas. It does not mean it was any easier to make wine in England then than now, and it might well have been much harder.

    William Hyde

  32. 32
    Geoff Russell says:

    If we do manage to get Governments to act and leave fossil fuels in
    the ground, RealClimate will deserve much of the credit. And if we
    don’t, then nobody can say that YOU, at least, didn’t do their best.

  33. 33
    Deep Climate says:

    #29 Re: Plimer on ABC “Unleashed”)

    Right. That’s the ABC piece I discuss in two recent posts (as well as a previous ABC interview) – (also see #28 above for my discussion of one of these).

    Also see Tamino at:

  34. 34
    David Horton says:

    #29 While “god responses” (“what are you idiots doing with that planet I gave you?”) is a nice thought, it should have read “good responses”. And sorry to have forgotten the excellent response from Deep Climate #33.

  35. 35
    Antonio San says:

    Bob Ward’s “Earth” must be an interesting exoplanet to study…

    Plimer’s book is a distraction to the main issues, a convenient distraction I may add for both sides: the Realclimatists will easily dump on this while the opposition thinks they are getting MSM mileage. One wonders if this whole business is indeed a pre Copenhagen set up in order to feature a caricatural figure opposing the true scientists… because so far, I read a lot about Plimer in Realclimate and other pro AGW blogs!

    The main issue is the artificial dichotomy between a so-called “chaotic” weather versus a general “climate”. It is the tell tale of ignorance of meteorological realities. Weather is hardly “chaotic” and obeys to the rules that govern the atmospheric circulation. Not knowing those rules doesn’t mean they do not exist.

  36. 36
    Garry S-J says:

    Re: David Erickson #17

    The media release ( )for the U of Rochester paper upcoming in Physics Letters A says:

    “The team believes that the oceans may change how much they absorb and radiate depending on factors such as shifts in ocean currents that might change how the deep water and surface waters exchange heat. In addition to the correlation with strange global effects that some scientists suspect were caused by climate shifts, the team says their data shows the oceans are not continuously warming—a conclusion not consistent with the idea that the oceans may be harboring ‘warming in the pipeline.’ ”

    Perhaps someone could provide some illumination.

    I had always thought “in the pipeline” in this context referred to an increae in the heat content of the system that will inevitably occur in the future as a result of a forcing (eg added CO2) which has already occurred, rather than heat that has already been added and will subsequently somehow come out of hiding.

    Helpful comments anyone?

    PS: RC team, thank you for all your good work.

  37. 37
    Scott Hastings says:

    Pardon me for not fawning all over the response provided by the gurus at realclimate like these others posting, but as a “climate retard”, please enlighten me on a question Dr. Plimer posed about CO2, that was derided by the respondents, but I believe IS relevant. Is not the sin qua non of AGW the huge spike in CO2 the last few decades? Ok, so if it is, what do you have to ACCURATELY compare CO2 levels from, say 5000 years ago to the current NOAA Mona Loa dry air mole fractionation? In other words, do you have a “rosetta stone” that translates CO2 findings from thousands of years ago to now? For example, do you account for entropy of C12, C13, C14 (I know about the probable stability of C12 and 13 already)? Do you account for the fact that CO2 in ice beds was NOT in dry environment (exposed to H20 and formation of carbonic acid or methane or other carbon substances) for thousands of years? As of yet, I have found no answer to this question! Funny, I would think this answer would be readily available as the theory of AGW rests on it (in my opinion)


    Just a lowly, unintelligent medical doctor and part time exxon oil CEO, (but only in your groupthink world) doing my own climate research.

    [Response: The ice core records have been verified by comparisons of cores in many different accumulation environments and they all match. They match historical data for multiple gases CH4, CFCs, CO2 etc, and show the same basic behaviour in both Greenland and Antarctica. The results fit the expected behaviour given the isotopes, the emissions, the ocean measurements, the decline in O2, Etc… If you think this is groupthink, then you have no idea what the science shows. -gavin]

  38. 38
    Lynn Vincentnathan says:

    Okay, enough with these idiot climate denialists already (but do keep up the tedious work of refuting them, please & thanks). Here are excerpts of a chastisement of us climate activists to stop prissy-footing around:

    The fallacy of climate activism
    by Adam D. Sacks

    In the 20 years since we climate activists began our work in earnest, the state of the climate has become dramatically worse, and the change is accelerating…

    I think that there are two serious errors in our perspectives on greenhouse gases:… The first error is our failure to understand that greenhouse gases are not a cause but a symptom,… The root cause, the source of the symptoms, is 300 years of our relentlessly exploitative, extractive, and exponentially growing technoculture, against the background of ten millennia of hierarchical and colonial civilizations…

    The second error is our stubborn unwillingness to understand that the battle against greenhouse-gas emissions, as we have currently framed it, is over. It is absolutely over and we have lost. There are three primary components of escalating greenhouse-gas concentrations that are out of our control: Thirty-Year Lag…Positive Feedback Loops…[and] Non-Linearity….

    Bitter climate truths are fundamentally bitter cultural truths….We can’t bargain with the forces of nature, trading slightly less harmful trinkets for a fantasied reprieve. Geophysical processes care not one whit for our politics, our economics, our evening meals, our theologies, our love for our children, our plaintive cries of innocence and error.

    If we climate activists don’t tell the truth as well as we know it—which we have been loathe to do because we ourselves are frightened to speak the words—the public will not respond, notwithstanding all our protestations of urgency.

  39. 39
    Guillaume says:

    Procedurally, George Monbiot should include each of RC’s answers as a footnote with the respective question. Ditto, for similar annotated answers from other sources. Links to whole articles can be provided in an appendix.
    I presume its fair game for “George Monbiot,” actual answers to these questions, as long as George Monbiot takes full responsibility.
    Of course, Ian Plimer would get the same courtesy, with the same acceptance of responsibility.

  40. 40
    John Pollack says:

    Thanks for posting a patient, educational response, RC.

    Regarding #16, the USDA plant hardiness zone map of 1990 for the period (U.S.) of 1974-86 reflects an era of unusually harsh winters, and the short period chosen is quite sensitive to that. In fact, the preceding 1965 version of the zone map was warmer in many areas. It was based on the 30 year period from 1899 to 1938, expanded as “readjustments were made for 34 states on the basis of January mean minimum temperatures for 1931 through 1952.” The 1990 map notes “We have been losing from our landscapes plants that apparently survived the 1940’s to the 1960’s. Many of the hardiness zone classifications of plants are no longer considered valid.” Yes, the winters of the 1970s and 80s were often colder than earlier in the century for the U.S.

    The winters since 1990 have generally been a lot milder, and a revision is certainly in order. However, I think a 30 year averaging interval is appropriate. The purpose of the map is not to illustrate short term climate change, as much as to indicate what plants can be expected to consistently survive the winter in various areas. As such, it is better to be conservative. Consider the possibility that an interval of somewhat colder winters could return, threatening the survival of tender landscaping plants. There is nothing in a picture of overall global warming that precludes one or even a series of regionally harsh winters.

  41. 41
    Lloyd Flack says:

    #3 Steve Missal,
    I think the payoff for Plimer is ego. If you find a scientist spouting quackery that will usually be the reason.

    #6 Bob Ward,
    I’ve noticed this happening in archeologists as well. Both archeologsts and geologists have to deal with climate changes in the historical and geological record. But they usually do not deal with their causes but rather take climate changes as a given thing. Deniers in these fields say why should we believe that current climate trends are anything different from the trends that we have seen in the past. They treat past natural climate changes as some sort of black box. And they treat current changes the same way. They are not used to looking at the detailed atmospheric and other data that is the basis for current attributions since such data is not available for the periods that they are interested in.

    This is of course my subjective impression and applies to only a minority of those in threse fields.

  42. 42
    Doug Bostrom says:

    Rattus Norvegicus 24 August 2009 at 2:01 PM

    “These questions read like a final exam written by a particularly cruel college professor who does not want anyone in class to pass the exam.”

    Presumably we’re to picture these requests as delivered down a prominent beak, from behind a pair of half-moon spectacles, in an arid and frosty voice. John Houseman’s stock character or the like.

  43. 43
    Martin Vermeer says:

    Garry S-J #35: Oh yes, your understanding of “in the pipeline” is the correct one.

  44. 44
    David Harrington says:

    My understanding was that Plimer offered to have a public debate with George and that thus far George has declined to agree to this? Is this incorrect?

    Can anyone clarify when and where such a debate might happen, I would be most interested in the outcome?

  45. 45
    Deep Climate says:


    Try cruising through the Canadian Society of Petroleum Geologists monthly newsletter (the Reservoir) of 2009 for Dr. Hutton’s denialist climate-change articles and its hodgepodge of the normal, debunked claims.

    Oh great the CSPG is back again (sigh). I guess I’ll have to check this out, since it is in my backyard.

    This is the same organization that published Chris de Freitas back in 2002 (when his brother Tim was editor of the Bulletin of Canadian Petroleum Geology). (De Freitas of course is one of the the trio that managed to get an abysmal purporting ENSO influence on climate trends published in Journal of Geophysical Research last month).


  46. 46
    Chris says:

    re #35 Garry S-J (and #17 David), here’s my take on this.

    1. The two phrases right at the end of the snippet you pasted Garry, comprise a delightful non-sequiter! The fact that the oceans may not be “continuously warming” doesn’t mean that they are not the main reason for “warming in the pipeline”.

    2. By “continuously”, I assume they mean “monotonously”. It is a no-brainer that the earth responds to enhanced forcing (e.g. from enhanced greenhouse gas concentrations) by evolving towards a new dynamic equilibrium temperature (as you indicate). This evolution occurs on multiple timescales (atmosphere responds quickly, oceans very slowly), so the limiting factor in the time evolution is the ocean response.

    3. Sometimes the oceans will absorb excess heat under the influence of enhanced forcing more quickly than at other times. During solar minima the ocean heat uptake will be reduced somewhat compared to during solar max. Volcanic aerosols will temporarily suppress heat uptake. During El Nino periods where warm surface waters are spread across vast regions of the Pacific, heat uptake by the oceans will be presumably reduced; alternatively during La Nina’s ocean heat uptake will be more efficient. It’s possible that the direction of heat flow might be reversed, especially following large volcanic eruptions.

    4. So the first statement of the press release snippet is a no-brainer too. Shifts in ocean currents will obviously influence the way that deep and surface waters exchange heat (and also heat exchange with the atmosphere). However that is certainly not inconsistent with the idea that the oceans “may be harboring ‘warming in the pipeline.’”. In fact there’s no “may be” about it! There has to be “warming in the pipeline” as a result of the slow response times of the oceans following a perturbation of radiative forcing.

    5. The use of the word “harboring” leads to a non-physical interpretation as you suggest. That’s press releases for you!

    6. I’ve just looked at the press release. I’d be surprised if the direction of heat flow into/out of the oceans has changed direction to a major extent during the last 30-40 years. But it surely has a little bit on an otherwise strongly increasing trend. That’s indicated in the published measures of the evolution of ocean heat content. There’s nothing revolutionary about that!:

    e.g. Levitus et al. (2009) “Global ocean heat content 1955–2008 in light of recently revealed instrumentation problems” Geophys. Res. Lett. 36, L07608

    one can look at their measurements of the time evolution of ocean heat uptake here, for example:

    see also:

    Domingues, C.D., (2008) “Improved estimates of upper-ocean warming and multi-decadal sea-level rise” Nature 453, 1090-1093

    a pertinent discussion of which can be found here:

  47. 47
    Hey Skipper says:

    A chillingly typical sentence is “A simple question does not get asked: what part of warming and cooling since 1850 is natural?”

    Almost all glaciers worldwide have been retreating for roughly the last 200 years.

    How much of that is natural?

  48. 48

    In July, Australian Prime Minister Kevin Rudd dipped his toe into the waters of blogging with an article on climate change. One Malcolm quoted copious errors from a book he didn’t identify though he mentioned Plimer’s name, to which I responded on my blog with the title “Monty Python Climate Change Phrasebook?“.

    I haven’t read the Plimer book myself (I skimmed through a library copy and decided it wasn’t worth the price to buy one); feel free to check my comments there (corrections welcome) to see if he was accurately quoting from Plimer. And have a good laugh before you go back to crying about the idiocy of supposedly intelligent humanity.

  49. 49

    Excellent post!

    I’m puzzled as to why Pilmer asked #10 and #11… did he actually think ‘climate’ is not being studied?

  50. 50
    Robin Levett says:

    @William Hyde #31:

    Following on from your comment; it is also fair to say that after 410 and before 1066 there wasn’t really much of a market for wine in Britain. We were largely ale-drinkers. The influx of a new wine-drinking aristocracy increased demand substantially.

    This an issue I raised when S Fred Singer visited Skeptics in the Pub in London last year; pointing out that the production of wine in Britain tracked very well indeed with economic and political factors, to the extent that using it as a temperature proxy (as he and Avery do) is absurd. The “acquisition” of Aquitaine in the mid-12th century and the Black death in the 14th explain the decline of the English wine industry into the LIA without any need to invoke the LIA itself.

    He wouldn’t answer the point – said it wasn’t his area of expertise…