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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. 201
    simon abingdon says:

    #178 Martin Vermeer

    “Simon sayz “Can you refer me to the relevant studies””.

    The answer I invited was “No” because (to my no doubt hopelessly inadequate knowledge) there has been none having the comprehensive global reach that I suggested was necessary to make such a claim (David B. Benson #172) as “Clouds are sufficiently well understood by now”.

  2. 202
    Steve Fish says:


    It took me some time to search up the comment list to find the one by Scott Hastings, currently labeled #160, that was added long after its posted time. I would be sorry to have missed your in-line references to that comment. What is the reason for this annoying practice of adding comments in the sequence, and renumbering the sequence, after we may have already read well past the insertion point.


  3. 203
    Rod B says:

    Ike (190), maybe yes, maybe no. Since the paleoclimate studies predominately show temperature increases leading temperature, this hardly supports the scale of AGW. You can’t say that we can tell how much the increase will be without models because we studied paleoclimate.

    I think that so far the 100 years of the instrumental record is far to sketchy to be conclusive. Though I would agree it at least points in a direction that tends to support the models. In any case it is still the models, not the physics nor the measurements per se, that are determining the scale of AGW; the instrumental record is used to validate the models (and the physics).

    If one can predict the NH global surface temperature 10 years out within .01 degree (±) with their paper, pencil, HP calculator and physics book, why are we spending all of this money on supercomputers and software?

    Maybe we’re passing in the night. You close with, “Models simply [sic] allow one to estimate the scale of those changes with some accuracy…” …which is pretty much my main point. ???

  4. 204

    #192 Rod B

    I agree. There are many complexities to balance here though and time is a serious factor. Spending on less rather than more effective solutions may also seriously impede capacity for meaningful progress as economic degradation ramps up due to scarcity issues.

    We won’t get through this without breaking some eggs and there will likely be more than a few choices that will be very hard to make on multiple grounds.

    Yes, knowledge will always be incomplete in this and many more circumstances, but this is what separates the men form the boys and the responsible from the frivolous.

    I’m not pretending any of the solutions in the pie will not have downsides and some will have more upside as weighed against capacity. Efficiency will be helpful but I fear it is the more difficult challenge in a world that loves to through money at solutions so that politicians can give the impression they have done something.

    I know I am still grossly oversimplifying the problem but this is a subject that is probably better answered in a dedicated discussion.

  5. 205
    tamino says:

    Re: #198, #199

    I’m reminded of a discussion I was in about funding a school in my hometown; everyone went on and on about government waste and inefficiency, high taxes and their burden on the middle class, etc. When my turn came I offered a quote from Mark Twain: “Every time you stop a school, you will have to build a jail.”

    It’s amazing how quickly my fellow citizens changed their minds.

  6. 206

    What a wonderful discussion and how decidedly different from the skeptic sites. I would like to add a quantitative dimension to the discussion on mitigation. The Sonoma County Community Climate Action Plan, referenced in the website, is a deeply researched study and set of conclusions on the most cost effective measures for CO2 reduction at a local scale across all sectors. The data we have produced in this plan conclusively shows that a publicly financed deployment of demand-side peak reduction, massively distributed generation, Smart Grid technology and electric vehicles can be financed using long term municipal bonds. The transformed energy supply portfolio can achieve a significant (25% below 1990 levels by 2015) reduction, cost effectively, and a head start toward carbon neutrality by mid-century. These findings are in line with the findings of the State of California that CO2 mitigation can be revenue positive for the state. I know this is off topic, but I note the well-worn skeptic objection that the energy supply transformation is “hugely expensive”… it simply isn’t.

  7. 207
    Russell Seitz says:

    it’s weird Plimer should invoke crack-seal processes , since some rock fracturing deformation releases radiogenic 3 He enough to provide a handy mass spec proxy for methane.

  8. 208
    David B. Benson says:

    simon abingdon (175) — Clouds are well enough understood for AOGCMs to track paleoclimates, over and over again. But not well enough to predict precipitation patterns with much accuracy, AFAIK. So of course more research is highly desirable.

    One recent study, of the northeast Pacific Ocean, shows that low clouds there provide a very small positive feedback to global warming.

  9. 209
    Phil Scadden says:

    Simon, it is the rich countries that the are the prime emitters of CO2 and need to get off CO2 not the poor countries. And if the rich dont, then climate change will hit the poorer much harder than the rich. Why do you pretend you dont know this?

  10. 210
    Rod B says:

    typo: my statement above should read, “…paleoclimate studies predominately show temperature increases leading CO2….”

  11. 211
    Rod B says:

    David Erickson (204): I appreciate their well intentions, but a County providing “…deployment of demand-side peak reduction, massively distributed generation, Smart Grid technology and electric vehicles…” for the County, and doing it ‘on the cheap’ no less sounds like a fantastic pipe dream rather than anything near a viable plan.

  12. 212
    Lawrence Coleman says:

    Re:191 Ike Solem. I totally agree! Do you think it’s because the US gov realises it’s too big a problem to handle on it’s own. It’s the world’s largest emitter of carbon based pollution and so the job of cleaning up it’s act is pretty well massive! I travelled through China in 1992 and was appalled by the thick layer of smog above virtally every city we visited. What’s quite bizarre as well is the lack of direct sunlight it’s this diffused light like from a flourescent light. So I am really pleased china is taking the initiative that america should be taking. Maybe china can lead america towards a cleaner world if it’s not already too late. In relation to the ocean fisheries..they are already like ‘dead fish swimming’. There are too many decades of increasing acidification locked into the system for it to have any hope of recovery lest not for the next few thousand years. Japan and the island countries will have a huge job of adapting their diet. Aquaculture will have to be the only way to go. So no more tuna, large pelagic fish or coral trout etc…better get used to a far lesser range of seafood to choose from. Us here in the SE corner of queensland australia have had record breaking heat last week..the previous record was 32.8C for August we smashed it two days running at 35.6C. As I type it’s still 31C and the mean for this month is 23C. In June we had a record beaking rainfall dumping 1.5M of rain in a few days. So in so far as australia is concerned the climate is definatley getting more extreme and unpredicable.
    In a nutshell we cannot afford to have a compromised copenhagan agreement..and waste another few years on top of the 10+ the years Geoge W wasted. The US must bite the bullet and send an unequivacal message to the world to drastically cut emissions now. It’s already too late in my opinion but we all have to fight for our lives..there is no truer analogy.

  13. 213

    #195 simon monckton

    I just noticed your note. It is interesting to note that this (like your #168) is the sort of illogical sound bite answer that is the problem in communication of relevant information. Your answer sounds logical (to those that don’t know the relevant contexts) only as long as it does not have the correct context, and of course you have not provided that context maybe/likely because you don’t know the needed contexts. You toss out a short blurb that sounds like it has meat but is really just a red herring (intentional or not). To answer it with context, I need to write a whole bunch of stuff based on the surrounding contexts. The main problem being that it’s easy to say ‘no one has proven Co2 is a greenhouse gas, or everybody knows plants need Co2 to grow, therefore Co2 can not be a pollutant. Non sequiturs, red herrings, straw-man arguments, lack of context/relevancy of facts and statements, appeals to emotion such as living the good life and political bias are the tools of naiveté, ignorance and myopia, they are not the tools of science and reason.

    Switzerland is a rich country. Many of the world’s countries are desperately poor. When energy costs more the poor get poorer. When food is swapped for fuel people die. And so on … Why pretend you don’t know this?

    The main logical fallacy with your post is that most of the poorer countries don’t consume massive amounts of energy like rich countries (and therefore do not bear the burden of culpability relatively speaking).

    Of course Switzerland is a rich country. I can see that with my own eyes, I live in Basel when I am not in California. But Switzerland, unlike other countries, read the McKinsey report and took it seriously instead of debating things like global warming stopped in 1998, and sea level stopped rising since 2006.

    Instead, they realized the physics were sound and the observable evidence is in our face, and voted to begin policy shift. The report does not say that ‘only Switzerland’ can afford to do this though (read it first, then comment). It was written for countries with industrial capacities and can have various degrees of cost/benefit based on speed of implementation.

    The longer we wait, the more expensive it gets. Period. Period!

    Of poor countries that still have a lot of poor people but are producing a lot of Co2 most have poor due to a lack of middle class. Furthermore, those poorer countries producing Co2 that still have a lot of poor are largely producing products for rich(er) countries. Therefore the chain of responsibility to the future cost is tied to demand/consumption, utilitarian, or not.

    What many need to learn is that balance in earth systems requires balance in capacity/cost weighted to source/demand.

    I am not saying there will not be challenges and changes. I don’t believe we can get out of this without some degree of change (some more challenging, some less) but the sooner we act the less impact on standards. This is of course logical.

    Those arguing we do nothing are the ones that should be taxed the highest as they are causing delayed action that will increase cost. I don’t want to have to pay for other peoples ignorance, they should have to pay for that themselves.

    Example: It is contradictory to hear corporations say ‘no regulation’ and ‘free-market’ like a mantra, and wear the facade of feigned responsibility in their pretense and communication; and then after abusing the system egregiously through various means of manipulation in marketing and legislative controls leading to economic system failures, to then scream we need corporate social-ism to save our companies in the form of bailout monies that are paid for by the very people they have been whining for years about making sure people don’t get a free ride while screaming social-ism every two sound bites. The hypocrisy is so thick you can cut it with a knife.

    I do not advocate giving monies out without attachment to responsibility and recompense without reasonable cause. But if everyone (corporations or people) want/demand a free ride in the developed countries while destroying the resource capacity, then inevitably the system will crash.

    Is this what you are advocating by continuing the impression that we just don’t know enough to make a decision, or are you truly that naive?

    Because that is the reasonably presumed world we are moving towards if we don’t move pretty darn fast in meaningful ways.

  14. 214


    Kiehl and Trenberth (1997) used a cloud scheme divided into high, middle, and low clouds, all with different properties.

    High clouds occur at 10-11 km altitude and cover 20% of the sky.

    Middle clouds are at 5-6 km and cover 6%.

    Low clouds are at 1-2 km and cover 49%.

    With random overlap, total cloud coverage over the Earth’s surface is 61.7%. This is a higher figure than was assumed during, for instance, the ’60s, because modern definitions of the area covered by a cloud are wider and mean cloud albedos are considered lower.

    Respective liquid water paths for the three types are 0.009, 0.020, and 0.036 kg/m^2. K&T didn’t give albedos, but using 0.22, 0.50 and 0.72, respectively, with a surface albedo of 0.15, I get A = 0.310 for the Earth, very close to the correct figure (0.306 according to NASA).

    Manabe and Wetherall (1967) used a similar scheme:

    High clouds, 10 km, 22.8% coverage, albedo 0.20.

    Middle clouds, 4.1 km, 9% coverage, albedo 0.48.

    Low clouds, 1.7-2.7 km, 31.3% coverage, albedo 0.69. Random overlap gives 51.7% of the sky covered overall.

    Clouds, of course, are also greenhouse agents. The UK Meteorological Office’s Hadley Climate Centre GCM, “UKMO HadCM3,” uses mass absorption coefficients of 130 m^2/kg for water clouds and 65 m^2/kg for ice clouds, which are typical figures compared to those in the literature.

    For the physics of how radiation interacts with clouds, Houghton (2002) devotes chapter 6 to the subject. The equation of radiative transfer is easily modified to deal with clouds.

    The web site NASA maintains for the International Satellite Cloud Climatology Project is here:

    These guys have been compiling observational statistics on clouds for some time now.

    The latest article on net feedback from low clouds (it’s positive), is Clement et al. 2009.


    Clement, A.C., Burgman R., and J.R. Norris 2009. “Observational and Model Evidence for Positive Low-Level Cloud Feedback.” Science 325, 460-464.

    Houghton, John T. 2002 (1977). The Physics of Atmospheres (3rd Ed.). Cambridge, UK: Cambridge Univ. Press.

    Kiehl, J. and K.E. Trenberth 1997. “Earth’s Annual Global Mean Energy Budget.” Bull. Amer. Meteorol. Soc. 78, 197-208.

    Manabe, S. and Wetherald, R. T. 1967. “Thermal Equilibrium of the Atmosphere with a Given Distribution of Relative Humidity.” Journal of the Atmospheric Sciences 24, 241-259.

  15. 215

    #199 Rod B

    En Addendum to #202

    There will be may flitches we will have to deal with ;)

    “solutions in the pie” could have also been “flitches in the pie”

    Sorry, I realized that I missed an opportunity in my response to use the word and could not resist the opportunity as I doubt I will ever use it again.

    It’s a silly world, but it’s our home.

    #203 tamino

    What a wonderful quote :) thanks for the reminder.

  16. 216
    simon abingdon says:

    Gavin – do you think this paper is important enough for a thread?

    Meehl, G.A., J.M. Arblaster, K. Matthes, F. Sassi, and H. van Loon (2009), Amplifying the Pacific climate system response to a small 11 year solar cycle forcing, Science, 325, 1114-1118.

  17. 217
    Joel Dignam says:

    This is a great read.
    I thought I’d share my own Ian Plimer experience, as it is pleasantly relevant:
    I saw him and Prof. Barry Brook speak in a debate on climate change – anthropogenic, or not?
    Afterwards, there was question time, and I asked him, essentially, what evidence would make him think that climate change was happening and man-made? (Obviously none, as his position is dogmatic.)

    He didn’t answer and instead launched into an ad hominem attack on me, spitting forth rhetoric. Yeah…nice.

  18. 218
    Hank Roberts says:

    An overwhelming need to put people down usually finds a way out, whether from a podium or a publisher or a barstool or a sidewalk. Some people just gotta vent or they’d puff up and explode, I guess, and the details are secondary to the need.

  19. 219

    Joel — attacks like that are one’s badge of courage. One is known not only by the friends who admire but also from the enemies who heap scorn.

    From what I’ve read of Plimmer I would consider it an honor to be verbally chastized by him and his like.

  20. 220
    Alexandre says:

    Totally off-topic, sorry, but I couldn´t resist.

    A “Institution of Mechanical Engineers” claims to have developed an artificial tree that absorbs 10 ton of carbon a day at the price of US$20,000.

    Here´s the article at BBC:

    Here´s the intitution´s report:

    Could someone say if this is for real?

  21. 221
    Hank Roberts says:

    > an honor to be verbally chastized by him and his like.

    You can buy satisfaction of this sort of taste at many discreet establishments without doing it in public and wasting everyone else’s time and bandwidth.

  22. 222
    Hank Roberts says:

    Point being, media love people like that guy because he antagonizes people and promotes controversy. Look at the mess he made of the evolution issue when he was using that as his excuse to vent bile.

    You won’t find the media giving attention to E.O. Wilson’s outreach to people on evolution and climate — reaching out and teaching isn’t going to sell advertising space and clickthroughs.

    There’s just no business model for teaching. Funny thing about that — read Tom Paine on the subject. Excerpt and pointer previously posted here:

  23. 223
    Rod B says:

    Barton, a couple of clarifying questions: Is “water path” the mass (kg) of water in a column one m^2 and the length of the various cloud types — each one km in your example? Where does the 0.15 surface albedo come from, as most sources say around 0.07; what is its effect on your analysis (which is interesting BTW)?

  24. 224
    simon abingdon says:

    #213 Barton Paul Levenson – I did make reply thanking you for your interesting response but it seems to have been lost in the post.

  25. 225
    Chris Dudley says:

    Alexandre (#218),

    Direct capture of carbon dioxide from the atmosphere in under development and the report you link is a pretty good summary. Capture from the atmosphere is more difficult than capture at a cement kiln or power plant. The way things are shaping up with the cost of renewable energy, leaving carbon in the ground is going to be the lowest cost mitigation after conservation but there may be a role for these machines to cut the atmospheric concentration of carbon dioxide once we have stopped fossil fuel use.

  26. 226
    simon abingdon says:

    #214 John P. Reisman (OSS Foundation) – your phrase “en addendum” looks as if it means “additionally” but in a language with which I’m not familiar. What is it?

  27. 227
    David B. Benson says:

    Alexandre (218) — The IME is the British equivalent of the US’s ASME. The problem with artificial trees is the energy costs of cleaning the captured CO2 out of the sorbant. AFAIK this still remains quite expensive.

    Making and burying biochar is a partial solution best suited for the parts of the world with high plant growth rates and low labor costs. So is increased use of biodiesel made from non-food vegetable oils.

  28. 228
    Susan Anderson says:

    It is important not to underestimate the concerted effort to kill the messenger on climate change. The IPCC is vilified because thousands of repetitions of a lie begins to make people believe it. The most effective communicators are the ones most attacked (e.g., Gore, Hansen). We see this currently in the easy lie “death panels”. This kind of effort is not wasted on minor issues but concentrated on those who are regarded as “dangerous” to special interests and their fellow travelers.

    It has been said elsewhere but bears repeating that delay is success. It is easier to destroy than to build.

    On the IPCC, it’s interesting that the basic idea that the world did its best to put together an international series of authoritative studies is not well understood by people in general. They are too easily persuaded it was some kind of limited insider effort.

    There are so many techniques, such as attacking the language and pointing out typos (see 224), subtly modifying what someone says and then ridiculing it (most likely the originator will not be able to do the careful work to point this out until the damage is done, but it is helpful as the lie is thereby revealed), turning words on their heads (pollution enabling labeled “clear skies initiative”, “true believer”), making the issue about the commenter instead of their ideas, etc.

    The insistence on a need for debate (with selected “experts”) ignores the fact that science is one long arduous continuous debate.

    I join in thanking Tamino 204 re Mark Twain!

  29. 229

    #224 simon monckton

    You mean you still have not figured out how to use the ‘internets’?

  30. 230
    Guy says:

    Any update from Pilmer or Monbiot on this article?

  31. 231
    Eli Rabett says:

    The artificial tree things is a crock. First you have to obtain (mine/refine/chemically and mechanically prepare) the capture agent. Then you have to move it to the artificial trees. Then you have to take it down from the trees. Then you have to move it to where you are going to bury it.

    Contrast this with a normal tree.

  32. 232
    Hank Roberts says:

    > artificial trees

    There must be something like stem cells in plants that could be used to grow more of the parts we want, on substrates we can manipulate, in large sizes — more easily than redesigning Creation from scratch to be build industrially.

  33. 233
    Mark S. says:

    I ran across this article “It’s Time for Some Due Diligence on Global Warming Claims” by Denise Moran:

    It denies man made climate change for various reasons. Since I’m new to this area I would appreciate help with a response to Moran’s claims which I or someone could post on the site in which his article appears.


  34. 234
    Alexandre says:

    Thanks for the responses to my OT comment. Since it is off topic, I´ll understand (and be thankful) if someone directed me to some other topic or blog where the subject can be developed without polluting the existing thread.

    I understand real trees have a whole set of benefits besides carbon sequestration. I would not use artificial trees as an excuse to relax conservation or to replace trees entirely.

    But they say 10 ton a day!! That would likely be more than enough to offset other emmisions in the chain (like transport to and from the capture site). And remember pre-industrial levels of CO2 included a large world forest cover AND a lot of carbon buried in the form of fossil fuel. We won´t capture that all back just with natural trees. And the long tail of residual CO2 after we limited emmissions -let´s be optimistic- is a problem already addressed here in RC.

    I´d really like to see some more detailed analysis of this kind of alternative. Something deep enough either to conclusively dimiss it as a crock or to point true possibilities.

  35. 235
    ghost says:

    RE: Rod B. # 202:

    Maybe we ARE passing in the night, but it seems to me that your statement “Since the paleoclimate studies predominately show temperature increases leading CO2….” implies more value to its precise wording than is justified. The paleo sequence has been dissected rather extensively here, e.g., . If your invoking of the concept is consonant with the science discussed there, then my apologies for expanding a molehill. If it is not, then perhaps you would elaborate on your view of this often mis-characterized proposition.

  36. 236
    Hank Roberts says:

    Mark, two suggestions, speaking as just another reader here.

    First, look up the website, and the people who own it and write for it.
    Search the author’s name at Wikipedia and at Sourcewatch.

    There’s little use getting sucked into an argument at a forum owned by people who won’t listen, who are in the business of doing PR for an industry — particularly when you are new to the information you’re trying to find to argue with. You’ll end up looking uninformed — because you are.

    This isn’t something you can help with just by picking up sound bites and transporting them from one blog to another.

    Lots of people do that. It’s just noise, it looks like activity.

    Advice: start with the “start here” links at the top of the page.

    Make your goal to learn where the science can be found and learn it for yourself. Get good at that.

    Then help other people find it for themselves.

    You’ll often see people shocked to have found some PR talking point like those, asking for others to come refute them at one PR blog or another. It’s a distraction and waste of time.

  37. 237
    Michael Jefferson says:

    For over 300 years our knowledge has been increasing about atmospheric chemistry (from Edme Mariotte onwards), and although uncertainties persist (about water vapour, clouds, albedo, and – above all – solar variation) the basis for believing anthropogenic greenhouse gas emissions tend to raise near surface global climatic warming are fundamentally indisputable. Those who have ‘global warming religion’ will tend to overstate their case (especially by deriding natural variation), and there must be question marks about the effort being put into large and excessively complex global climate modelling 100 years out. On the other hand, perhaps the most severe criticisms should be addressed at US oil and coal interests ‘in denial’ in the run-up to Copenhagen UNFCCC summit(reminiscent of the old Global Climate Coalition) and the ‘greedy’ renewable energy ‘Pretendees’ – those who want to put up wind turbines where mean wind speeds are low (but electricity consumers’ subsidies still high), who want simply to burn palm oil thousands of miles from where tropical forests have been destroyed, and those who want to divert rapeseed oil from human and animal use to simply burn the stuff in tiny electricity generating plants (not even hot pressing it for a 44% oil yield, but cold pressing it for a 28% oil yield). It is claimed the UK planning system is holding things back, yet peer-reviewed research demonstrates that the UK system is as helpful to renewables as that in Germany (though at higher cost than the Feed-in Tariff System), and quicker/more reliable than those in Spain and Denmark. Of course, as many of you will expect, neither the UK government, nor the UK planning system, nor the UK Advertising Standards Authority are particularly hot – but that is another story requiring very detailed treatment.

  38. 238
    David B. Benson says:

    Alexandre (231) — Unfortunately Eli doesn’t understand how so-called artificial trees are expected to function. One passes air over the sorbant which captures the CO2. Once full up, flaps to the air are closed and flaps to the CO2-only pipe are opened. Now comes the expensive part, removing the CO2 from the sorbant so that it flows into the CO2 pipe. Once cleansed, start over for another cycle. Nobody is proposing just sequestering the sorbant filled with CO2.

    If the proper sorbant/catalist pair is found then the costs are not too bad. It has been proposed to use stranded wind/solar to energize the artifical tree cycle. Then I suppose it is only capital and maintenance costs to be considered.

    Most research these days is directed towards sorbants suitable for removing CO2 from flue gas. That is actually an easier problem but still a long way from commercialization.

  39. 239
    CM says:

    Mark S. (#230), the author of the article you link to takes issue with the claim “that the recent warming is due mainly to global warming gases produced by mankind”. He claims to have trawled the literature but not found any “good” work supporting this claim, though he doesn’t explain what makes him qualified to evaluate the science (a BS in mechanical engineering?! I mean, come on).

    Since he defines “good” work as “analyses that use validated models and reasonable assumptions that have a sound basis”, and invites anyone who’s seen such work to share it with his readers, I suggest you refer him and his readers to the IPPC Fourth Assessment Report, working group 1, chapter 9: Understanding and attributing climate change.

    Tell him if he doesn’t like what the science says, to be specific: what in his view is missing from the validation of the computer models referred to there, and what unreasonable assumptions are made. Perhaps from there on, you can make some progress.

    Oh, and don’t let him get away with silliness like “the [global temperature] trend has been downward in the last several years”, which shows he doesn’t grasp the difference between trend and noise. You may want to point out that the past decade has been the warmest on record and the 30-year trend remains solidly upward..

    Finally, since he leans heavily on the “NIPCC report”, have a look at Bart Verheggen’s post on that tome, with links.

  40. 240
    Phillip Huggan says:

    #1. Size of medieval warming: 0.4-0.7C. Size of warming this (not even considering beyond this) century worrying the scientific community: 10x that.

    #2 AFAIK requires the CO2 satellite that just failed. Deniers are lobbying for more scietific research. Good.

    #3 is currently unknown. That means the truth may be better or worse than average. There is an esoteric (I just learned this year) economic calculation that says insurance for regressive events is more expensive than is the ecoonmic gain in experience the mirror identical economic growth event. Losing $100T is more expensive than is gaining $100T or $110T. Deniers are arguing here uncertainty means to be even more prudent. Admnittedly tough economics but they are completely discounting uncertainty predicates things may turn out worse than average.

    #4? WTF?….I’ve lost interest in continuing reading their writings…

  41. 241
    Steve Fish says:

    Mark S., ~#230. In a good skeptic’s toolkit is– Any scientific claims should always be backed by citations to scientific publications. Because Moran didn’t provide evidence that can be checked, you should discount all that he said. This fact, by itself, does not mean that what Moran said is necessarily incorrect; it does mean that what he said carries no weight whatsoever.

    If you wish to find what the science actually says about all of his claims, the information WITH scientific citations is available on this RC website.

    If you wish to post a question on the Moran blog that will not be answered, and thereby confirm the skeptic diagnosis, ask for the names of 31 signers (less than one thousandth of the total) of the Oregon petition( that are scientists with a climate science publishing record. If any names are provided, you can easily check their publication records on Google Scholar.


  42. 242
    Geoff Condick says:

    I don’t see how the use of jargon by Plimer is used as you claim to muddy things. I’m sure it makes perfect sense to a geologist. Have you ever seen a mining prospectus? Now that is FULL of jargon.

    [Response: They generally aren’t written for a journalist in the mainstream UK press. In that context, the use of irrelevant jargon is merely to try and confuse. – gavin]

  43. 243
    Rod B says:

    ghost (232) my contention was that global climate models are essential to estimate or project the degree of global warming, and that the paleoclimate studies can’t be used in place of GCMs to justify/show it. This discussion wasn’t over the paleoclimate studies per se.

  44. 244
    CM says:

    Mark S. (#230), then again, you should probably take Hank’s sound advice (#233), not mine…

  45. 245


    Yes, “liquid water path” is specific mass, mass per unit area. The 0.15 figure for Earth’s surface albedo is one typically used in GCMs. I’m not sure where the 0.07 figure came from.

  46. 246

    Mark S, you could start where the articles does–with the claim that it has been cooling since 1998. My (deliberately simplistic, but I believe accurate) counter to that follows.

    I downloaded the UAH satellite low-trop data (the “denialist’s dataset) giving global monthly mean temperature anomalies. I loaded it into a Excel spreadsheet and computed the monthly means for ’89-’98 and also for ’99-’08. The results:

    90s: 0.04367 C
    ’00s: 0.20025 C

    This analysis makes no explicit claims about trend. But if by “cooling” what’shisface means that you can expect a month to be .15 C warmer, then IMO he’s living where Lewis Carroll loved to explore. :-) (And note that this accepts the cherry-picked 1998 baseline.)

    As with my sea-ice spreadsheet, I’d be glad to e-mail you or anyone else the spreadsheet for verification or further development.

  47. 247
    Geoff Wexler says:

    Re #33

    The Revolutionary Geologist?

    Promoters of Plimer emphasise his credentials as a geologist. I know very little of his subject but it seems to me that his colleagues will now have a lot of readjustment to do. Will this turn out to have been a paradigm shift?

    Tamino’s article linked by Deepclimate at #33 is an excellent discussion of some of this geology and is followed by some perceptive remarks which can just about be detected in the very noisy thread which follows it. Look out for the remarks by Divalent and TrueSceptic. Without checking the arithmetic it appears that Plimer is implying that 30% of the eruptions from super-volcanoes like Toba (30 M years ago) must have consisted of CO2. This ‘discovery’ must surely have dramatic implications for the composition of the Earth?

    [With apologies for not submitting this comment to Tamino’s thread but that particular thread appears to have more or less ended]

  48. 248
    Rod B says:

    Barton (240), that seems odd. The standard Trenberth and Kiehl budget graphic shows 6.7-7.0% surface albedo. Are you/they using different surface types, maybe? Or am I reading it wrongly (though it seems pretty clear…)??

  49. 249
    Russell Seitz says:

    re Barton Levenson 245:

    ” The 0.15 figure for Earth’s surface albedo is one typically used in GCMs. I’m not sure where the 0.07 figure came from.”

    .07 is a reasonable figure for lake or ocean water albedo , including phytoplankton , whitecap and microbubble backscatter.

  50. 250
    Mark says:

    “Both low and high clouds retain heat from below more than they reflect light from above during the night. Basic science says so.”


    I sit corrected.

    Simon, do you know that there is going to be a generally cooling effect from clouds?

    If not, how do you know that clouds are going to make the problem disappear?