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Comments 69001 to 69050:

  1. Changing the Direction of the Climate
    According to his website, "Michael Den Tandt is a national political columnist for Postmedia News, publisher of the National Post, Ottawa Citizen, Montreal Gazette, Calgary Herald, Vancouver Sun and Halifax Chronicle-Herald." Not a reputable scientific source.
  2. Schmittner et al. (2011) on Climate Sensitivity - the Good, the Bad, and the Ugly
    dana1981 writes: "neal - it does appear that the models are related. For example, the UVic sea ice module was included in CCCMA, and the UVic model is extensively used in developing and testing the CCCma model. But it's not a critical point, and if it exaggerates the relationship between the two (which is unintentional, if so), I don't have a problem with removing that section." Thank you for removing that section, but what you say above is also false. I am a CCCma scientist and have extensive experience with the CCCma models, and well as with the UVic model and many other models. These models share some common features, as do all climate models -- but beyond that they have been developed and tested independently of one another. This is not a big deal in terms of what you're debating in your post, but I correct you all the same.
  3. Peter Hadfield addresses the recent email release
    Ditto - what tmac57 said.
  4. It's the sun
    the end of comment 914 indicates Don Gaddes compiled these numbers in 1990. I am curious how accurately his calculations predicted the global average temperature for the years 1990-2011.
  5. The Debunking Handbook: now freely available for download
    Apologies, I meant Page 8 (eight). Second to last paragraph, just before the bibliography, reads, The gap created by this debunking is the question “how can there be a 97% consensus if 31,000 scientists dissent?” This gap if filled by explaining that almost all the scientists in the Petition Project are not climate scientists. Please replace "This gap if filled..." with "This gap is filled..."
  6. The Debunking Handbook: now freely available for download
    I would like an ebook format (epub) too. I would pay for it.
  7. It's the sun
    Don Gaddes - Well, that's a lot of numbers. But do they mean anything? The temperature of the Earth climate is determined by the amount of energy in it - which in turn is driven by the rate of energy in (sunlight, throttled mostly solar output and Earth albedo) and the rate of energy out (throttled by temperature, IR emissivity of Earth to space). You seem to be claiming that current temperature changes are driven by cyclic phenomena, not CO2 and other greenhouse gases. Unless these 'cycles' determine the rate of energy entering or leaving the Earth's climate, somehow modifying insolation (in ways that are not currently detected by TSI studies), albedo (again, in ways not currently detected), or IR emissivity to space, they are essentially "climastrology", "numerology". Tamino has discussed this exercise, and has most appropriately labeled it Mathturbation. Given sufficient data and imagination, it's possible to fit any natural phenomena to 'cycles', but unless there is a physical basis affecting energy rates you are looking at correlation without causation. How do these various cycles physically affect the energy balance of the climate - in some measurable fashion? Without that, these 'cycles' are simply a pointless intellectual exercise...
  8. Changing the Direction of the Climate
    Thanks
  9. Economic Growth and Climate Change Part 2 - Sustainable Growth - An Economic Oxymoron?
    perseus : I remember the estimates of Jackson in the chapter on the ‘myth of decoupling’, but I cannot examine precisely this for now. I think he is globally right, but I’d like to check the rate of energy intensity gain really implemented in some models (there are probably an inverse function of substitution rate). To be sure, a 450 scenario is at least a ‘gamble’ but I agree with Tom’s answer above. Not a substantive but a pragmatic consideration: take the time necessary to reach a policy consensus on negative growth ou zero growth, and we will probably double the CO2 concentration! Bluntly put : if, in a democratic system, people were really to choose between the immediate consequences of an organized stagnation / recession and the distant consequences of a 2K or 3 K warming, I bet most of them would prefer the second option. At least in some countries and, as 15 years of climate negotiations have shown, a global consensus on solutions is requested, because local efforts (like Kyoto Protocol) didn’t produce significant effects on emissions rate. adelady : I agree, but this is probably a matter of pace and scale. Small changes will cause small debates and opposition. For bigger change, you must anticipate much more resistance IMO. And there is also the macro-economic effect of an ambitious energy transition plan. If you take for example all the direct and indirect jobs related to car use in transportation (not just the engineers and workers in production industry, but all services, products and value chain centered on car), it is uneasy to plan a revolution in one generation. At least, the hypothesis of zero social friction is a gamble !
  10. It's the sun
    My apologies if I misinterpreted DB's moderation comment @909, I did not ever see your original. I will use a more friendly tone from here on if you will do the same. The evidence you provide in @914 is not the least bit helpful without some context. It is just a Number Salad. Please provide an outline of your argument because at this point I have no idea what it is your numbers are supposed to show me.
  11. Changing the Direction of the Climate
    jimb - see our CERN rebuttal
  12. Economic Growth and Climate Change Part 2 - Sustainable Growth - An Economic Oxymoron?
    I'm not sure Tom, it may proove more expensive to deliver a near zero carbon energy system than to stop economic growth. As an Engineer I know how hard and expensive it will be to deliver this without a scientific breakthrough. It might be possible to deliver 20% at present though green energy without breaking the bank, but a 80-90% reduction for an increased economy and population is a totally different matter. The demands on materials, storage costs, design for worst case meteological conditions is staggering. If we are struggling now, you haven't seen nothing yet. Simply foregoing needless toil and rubbish is so much easier than 9 bllion people forever trying to catch up with the Jones' Neither can I see any reason why simply forgoing buying even more stuff should lead to a crisis. Reductions in economic growth have previously been driven by some underlying crisis such as war or famine, and we are talking about steady state economy not a reduction. Japan has been a steady economy and a reducing population for 20 years now yet I see no evidence of widespread suffering or lack of innovation. Sometimes it can be better to be honest and tell people straight what is necessary to do the job 'Ask not what your country can do for you - ask what you can do for your country' or fellow human or planet in this case, rather than weak promises of ever greater riches. They might actually believe that. I guess the route is to move away from GDP metric altogether and towards a quality of life index then at least you could show them real improvements, than through fantasy economic figures.
  13. It's the sun
    Yes, I was 'banned' and reinstated, with further (-snip-) warning. No, I did not try to sell anything, I offered a free pdf of the 'proofs'. (-snip-) Anyhow, here is a small taste. If you are still interested you can pursue the rest. Earth's Period (No. 1 Constant) Divided by 4 (Obliquity, No 2 Constant) = Quarter Year Multiplied by 27 (Ratio, No. 3 Constant) = 6.75 Years (Regional Drought Cycle) Multiplied by 11.028148 Yrs (Sunspot Wave Frequency, No. 4 Constant) = 74.44 Years ( Quarterly Sub-cycle of a full 297.76 year Sunspot Cycle) Divided by 4 (Obliquity, No. 2 Constant) = 18.61 years (Metonic Cycle of the Moon's Nodes.) Multiplied by 27 (Ratio, No.3 Constant) = 502.47 Years (Full Tree-ring Cycle, 3x167.49 Year Tree-ring Sub-cycles.The 167.49 Year Sub-cycle is in turn made up of 9x18.61 Year Metonic Cycles of the Moon.) Multiplied by 11.028148 Yrs (Sunspot Wave Frequency, No. 4 Constant) = 5,541.3135 Years (Which equals 2x2,770.6567 Year Glacial Cycles, See J Bray.) Multiplied by 11.028148 Yrs (Sunspot Wave Frequency, No. 4 Constant = 412,495.34 Years (=?) Divided by 4 (Obliquity, No 2 Constant) = 103,123.83 Years (Precession of 'Perehelion and Aphelion') "According to Strahler,(Ref. No.17.) the rotation rate of the Sun differentiates at a slower rate from lower to higher latitudes. It seems to me that we ought to be investigating the latitude of the Sun which is rotating at the 27 day rate." (A S Gaddes, 1990.)
    Response:

    [DB] Inflammatory tone snipped.

    "I offered a free pdf of the 'proofs'."

    If no peer-reviewed published citable sources exist your claims devolve to "climastrology".  QED.

  14. Changing the Direction of the Climate
    One reason we may end up 'wait to implement serious mitigation' may be found in op-ed pieces like the one in our local paper this morning, titled "Of course, Canada ditched Kyoto commitments". The author, Michael Den Tandt writes as follows: "The skeptical science, for years confined to the scruffy margins by the International Panel on Climate Change and its supporters, took a huge leap forward with the discovery by no less than the CERN laboratories based in Switzerland-arguably the most prestigious scientific group in the world-that fluctuations in the sun's magnetic field have a very large, perhaps dominant effect on the earth's climate." He continues "the CERN findings are steadily trickling through the blogosphere, quietly altering the political discussion everywhere..." The only thing I can think he is referring to is the CERN work relating cosmic rays to cloud formation, but I get most of my climate science from this site. Hopefully, someone more familiar with the science than I am can stop this trickling before it drowns the discussion.
  15. Peter Hadfield addresses the recent email release
    Another excellent piece of work by Hadfield.We all owe him our gratitude for fighting the disinformation that seems nearly bottomless (in more ways than one).And of course the same appreciation goes out to SkS.
  16. Climate Solutions by Daniel Bailey
    In the UK the vast majority of people don't need the types of vehicles they use and could easily make do with smaller vehicles. People make up excuses for buying a vehicle with large carrying capacity, stating things like: 'it would be really useful for carrying a lawnmower to the repair company, or for picking up some timber from the DIY store'. Yet they often only ever do this once or twice a year or even never! So the reality is they could have got the store to deliver for a fraction of the cost of the the fuel and materials needed to build and use the bigger vehicle. Yeah a few people 'need' them, but most vehicles are driven with just the driver at the wheel 90% of the time. Plus of course cars need a lot of parking space at various places to cope with the probability of someone needing a parking space.
  17. IEA CO2 Emissions Update 2010 - Bad News
    dakiller6, the SRES tables you link to show gigatons of carbon ("GtC")... figure 1 above shows gigatons of carbon dioxide. Basically, one set of figures is counting only the mass of the carbon atoms while the other is including the two oxygen atoms as well.
  18. Peter Hadfield addresses the recent email release
    Oh...well done! Simply wizard!
  19. Climate Solutions by Daniel Bailey
    WRT living closer to work, this is not always a reasonable solution. In my case I live relatively close to my primary employer and plan to move farther away as the neighborhood is not good. My 2nd job (which I work remotely 90% of the time) is in an even *worse* area. Moving to a nicer area and commuting might be the wrong environmental choice but the right one for my family.
  20. It's the sun
    You are still posting so you are not banned (see post 911). If you want to discuss the science here then discuss the science. State your case and provide your evidence. Provide links to more details if it is too much for a single post. This is not rocket surgery, it is basic conversational skills. "Buy my book to learn the Truth" is not at all the same thing.
  21. IEA CO2 Emissions Update 2010 - Bad News
    Hello, I just registered to ask a question on this article. I am a Ph.D student on atmospheric science but my main area of research is cloud physics ('aerosol indirect effect' which is covered in IPCC WG1 report) and I am not familiar with CO2 emission (instead of concentration) statistics or anything treated in WG3 report. I found this article very interesting (and alerting!) and want to introduce this article at a forum whose main attendances are non-scientists, which is part of volunteering work for environmental movement here in Korea. My question is, why are the numbers for SRES scenarios in the Figure 1 (which is around 20~30 Gton/yr) different from the numbers of Fossil Fuel CO2 provided at the SRES website (http://sres.ciesin.org/htmls/data_list.html), which is lower than 10Gton/yr? There must be some sort of notion difference between them. If it's too much work for you to explain, a nice reference will do. Thank you.
  22. Climate Solutions by Daniel Bailey
    I would add that an area for big potential savings in energy consumption and CO2 emissions is not just what or how much you drive a personal vehicle, but how you drive it. Unnecessarily hard acceleration kills your vehicle's efficiency. One study from a dept. of the US gov't (EPA, I think) found that avoiding hard acceleration would save the average American driver (who drives like a movie stunt man on a bad acid trip) about 30%(!) in fuel consumption. Add in other obvious savings like not carrying a lot of dead weight in the vehicle, keeping tires properly inflated, not speeding, etc., and the average driver can easily see real world improvements about equal to swapping their car out for a hybrid version of the same model. I drive a Scion xA and routinely get 40 mpg, which is above the EPA rating for that model (when it was still in production). We certainly need to change the nouns and verbs in our lives (what we buy and what we do with it), but we also need to change the adjective and adverbs (how we do things).
    Response:

    [DB] I have found that I improved my gas mileage by 6 mpg by reducing my average speed from 5 mph above the speed limit (yes, I was one of the masses who routinely flouted the speed limits) to 1 mph under the speed limit.  Much better mileage and no chance of speeding tickets.  And lower blood pressure.

  23. Economic Growth and Climate Change Part 2 - Sustainable Growth - An Economic Oxymoron?
    skept.fr "That is particularly true for a fast transition – people and society are not so flexible." I'm not so sure about that. afaik, most people really don't care how their power is generated unless they have a job in a mine or a generation facility. For transmission infrastructure, some engineers might be stick-in-the-muds who'd like to keep doing what they've always done, but there are many who'd really like to see more efficient and effective distribution systems. Users rarely care about the details as long as the power stays on. As for industry. Just pick the low-hanging fruit to start with. If they can save money on airconditioning and lighting - esp for administration facilities which they see as a cost burden on their productive processes anyway - they'll get a taste for it. And then look for ways to do things better with their core operations. For transport. People who already use public transport will welcome any improvements in services. People whose access to such services is poor at the moment will adopt useful services if they are provided. The only issue is how quickly they'll do so. It's just a question of design and how much governments or other agencies are willing to spend at start up before the frequency and quality of the service gets a good enough reputation for more and more people to use it.
  24. Economic Growth and Climate Change Part 2 - Sustainable Growth - An Economic Oxymoron?
    perseus @41, yes pursuing a low or zero emissions economy with continued population and economic growth is a gamble. That is the invidious position we have been placed in by the slow response to global warming. But ending economic growth as a deliberate policy, or population growth in the short term are not political possibilities, and shackling the response to global warming to those policies just makes any effective response to global warming less likely. Further, there is no instance in history (that I know of) in which either declining population or declining economies have not caused wide spread suffering. Further, rapid technological change with static economies will cause wide spread suffering as already discussed. So your proposal is also a gamble, and IMO a far greater gamble than the alternative.
  25. Schmittner et al. (2011) on Climate Sensitivity - the Good, the Bad, and the Ugly
    skept.fr @53, no! What I suggest is that one of the model warming ratios, the land proxy temperatures, the sea proxy temperatures, or both, are in error because of the discrepancy between the Warming ratio found by Schmittner et al, and that from models in Sutton et al. I further suggest based on the additional evidence of warming seas north of Iceland according to Schmittner et al's reconstructions that an underestimate of sea surface temperatures is at least one component of the puzzle, so that once the issue is cleared by further studies a higher estimate of climate sensitivity is likely to be one of the results. Further, regarding models, the UVic model is described as follows:
    "A globally-averaged lapse rate is used to reduce the model’s apparent sea level temperature in calculating the following: the outgoing longwave radiation; the surface air temperature (SAT) dependent planetary co-albedo through the calculation of the areal fraction of terrestrial snow/ice; the saturation specific humidity to determine the amount of precipitation; whether the precipitation will fall as rain or snow"
    and:
    "The other major simplification to the atmosphere is the parametrization of atmospheric heat and moisture transport by diffusion, although moisture advection by the winds is also included as an option (Section 4)."
    Ray Pierrehumbert comments on this at Real Climate:
    "What is more severe, in my view, is that the energy balance model cannot represent the geographic distribution of lapse rate, relative humidity or clouds. In the interview over on Planet 3, Nathan Urban clearly doesn't understand the full limitations of the model even though he is one of the authors of the paper. It's more than just failing to represent the albedo effects of clouds -- the model doesn't represent the geographical variation of cloud infrared effects either, or the way these change with climate. Given that clouds are known to be the primary source of uncertainty in climate sensitivity, how much confidence can you place in a study based on a model that doesn't even attempt to simulate clouds?"
    So, this is not just another example of GCM's disagreeing about climate parameters. This is a case the model not allowing the relevant variables that determine the warming ratio to be set by physics within the model. That is a fair enough choice given budget constraints, but it does have consequences. Further, with regard to the use of other models, James Annan writes:
    "Jules has also been looking at some of these data recently, particularly in comparison to the PMIP2 experiments - that is, simulations of the last glacial maximum by several state of the art climate models, most of which also mostly contributed to the CMIP3/IPCC AR4 database of modern/future projections. One telling point is that several of the PMIP2 models actually appear to fit the data better than Schmittner's best model, even though these were not specifically tuned to fit the data. Moreoever, these models are all clearly colder, in terms of global mean temperature anomaly, than the -3C value obtained in this latest paper. We haven't done a thorough analysis of this yet but I think it is safe to say that there is a significant bias in the Schmittner fit and that the LGM was really more than 3 degrees colder than the present. The implication of this for climate sensitivity is not immediate (since there are also well-known forcing biases in the PMIP2 simulations), but this line of argument also seems to suggest that it may be reasonable to nudge the Schmittner et al values up a bit."
    So initial indications are that use of an ensemble of AOGCMs would have resulted in a higher climate sensitivity than found in the paper. So, I think in this case we can consider AOGCMs, and certainly and ensemble of AOGCM's to be more realistic in this case (because UVic ignores physics for relevant processes) and that it does make a difference, and is likely to have biased Schmittner et al's results low. Again, this is not a flaw in Schmittner et al's study, but a constraint on it. I'm sure they would have preferred to use an ensemble of AOGCM's if somebody had ponied up the cash. Nor is it a conclusive argument that they are wrong. But it is certainly grounds for caution with regards to their result, and suggests that when all the smoke clears, they will be low estimate of the LGM climate sensitivity.
  26. Schmittner et al. (2011) on Climate Sensitivity - the Good, the Bad, and the Ugly
    skept.fr @52, they allow change in albedo due to changes in ice sheet as a forcing in the model. Because the change is ice sheet is treated as a forcing, it is not treated as a feedback. Hence there are no (or at least no large) slow feedbacks in their model, from which it follows that they estimate fast-feedback climate sensitivity.
  27. Schmittner et al. (2011) on Climate Sensitivity - the Good, the Bad, and the Ugly
    Most importantly, I think the central point is not how well UVic model deals with evaporation, lapse rate, etc. – it is very unlikely in my mind that a particular model can be considered as more or less realist in its simulation, see here for example (figure 8.14) the still important divergences among IPCC AOGCM for WV, lapse rate, cloud, etc. The land/ocean warming ratio is a starting point from the reconstructed temperature (new proxy data set), not an utlimate result from the model runs. The model just try to reproduced the temperature and it seems to me that you reason as if the inverse was true. If the new proxy reconstruction is correct, then the land-ocean ratio will have to be reproduced by any model, no matter its complexity (RCM, EMIC, AOGCM, etc.). What you suggest in fact is that the proxy results are probably false, because most models produce a land/ocean warming ratio incompatible with the new proxy-based temperature.
  28. Schmittner et al. (2011) on Climate Sensitivity - the Good, the Bad, and the Ugly
    #51 Tom : "In contrast Schmittner et al discuss fast-feedback climate sensitivity" This point is not clear for me. Their analysis deal with "annual mean surface temperature (sea surface temperature over oceans and near surface air temperature over land) change between the LGM and modern" (legend, figure 1). So in my mind, that is a 10 or 12 ka change between two equilibrium states, including what you call "slow feed-back".
  29. Economic Growth and Climate Change Part 2 - Sustainable Growth - An Economic Oxymoron?
    If these models conclude that we can preserve economic growth while substituting fossil to non-fossil energy sources in the next 40 years, I think we must conservatively give credence to these models for their realism (that is, we should prove there are wrong if we disagree with their conclusions). I thought Jacksons calculations would have laid this possibility to rest. Let me repeat it again: In his book ‘Prosperity Without Growth’ Jackson calculates how much we would need to reduce the product of energy intensity and carbon intensity (in units of CO2e/economic output) to meet a CO2e of 450 ppm by 2050 without adjusting GDP or population growth rates. In the absence of such controls, we would need to reduce this factor by 10 times faster than the present rate, that is a 21 fold improvement by that date relative to the present to meet this target! Some other scenarios regarding population or GDP growth would require a virtual complete de-carbonisation of our entire energy system. Nothing other than a revolution in energy generation could meet 450ppm whilst retaining economic growth. That is the gamble people are taking who reject this. Is this too different to the mentality of those who reject climate change altogether? Are they not all either Deniers or gamblers?
  30. Economic Growth and Climate Change Part 2 - Sustainable Growth - An Economic Oxymoron?
    For orders of magnitude, fossil fuels produce approx 425 EJ or 13,5 TW each year. Solar radiation on land surface at the exclusion of polar, subpolar and difficult access regions produces a suitable flux of 15 PW, nearly a thousand times fossil consumption. For wind energy, the theoretical estimate of accessible flux is approx. 70-80 TW, five times the fossil flux. Waves kinetic total energy is 60 TW, but for coastal exploitation the value is rather 3 TW, a fourth of fossil flux. Tidal total energy amounts to 3 TW, but just 60 GW on coasts. Geothermal flux is estimated at 42 TW, but mainly on ocean floor so the current potential on land surface would be 100-600 GW. Terrestrial photosynthesis proceeds at a rate of 60 TW, from which approx 3 TW are currently exploited. So the conclusion is clear : the total amount of renewable energy flow that humanity could exploit is far over the fossil fuel, with direct solar energy as the most important source. Without even mentioning nuclear fission or fusion. But as we are speaking of economic growth (and climate mitigation), I think the relevant question is not the total and theoretical energy flow for a long term transition (numbers above), rather the realist exploitation of this flow on short term (decadal rather than centennal scale). We should recognise that either on energy density (amount of energy per unit of volume) or on power density (rate of flow of energy per unit of surface of land area), most renewable sources are for the moment less efficient that fossil or nuclear. And that’s also true for energy conversion from total incoming flux to final service, particularly for solar processes (the main source from total energy flux on Earth). As 80% of our energy come from fossil sources, the other problem is the weight of installed infrastructures in transportation, industry, building, etc. as they represent capital assets and human skills (ultimately, jobs). These points are much more uneasy to estimate and that’s why we must rely on energy-economy models. That is particularly true for a fast transition – people and society are not so flexible. If these models conclude that we can preserve economic growth while substituting fossil to non-fossil energy sources in the next 40 years, I think we must conservatively give credence to these models for their realism (that is, we should prove there are wrong if we disagree with their conclusions). But for sure, from all that I’ve read, a strong effort toward the use of clear and similar indicators among energy-economy models is needed (as this have been done in IPCC WG1 climate models). For the moment, each model ‘tinkers’ its own energy mix and cost estimations, but in the public debate, we need much more clarity about what we can and cannot choose, and at which cost. Ultimately, economic growth and climate change are particular points of a larger democratic debate. I remember here the Mike Hulme’s interesting essay, Why we disagree about climate change. We, citizens, have different and sometimes discordant attitudes toward nature, technology, risk, well-being, etc. These attitudes ultimately depends on our psychological traits, ideological convictions or ethical beliefs. What we can do here is to precise the basic facts, then to clarify our interpretations and to test their coherence, but I would say there is no reason (and probably no hope) to reach an ultimate consensus. That is particularly true for our most subjective judgments on capitalist or market-based societies. As a regular reader of 'degrowth' (negative growth) advocates, like for example Serge Latouche or Philippe Ariès for French authors, I observe that the frontier between growth as physically impossible trend and growth as ethically undesirable attitude is not very clear. As Tom put it in a previous message, a substantive judgement on growth is welcome as a starting point.
  31. Schmittner et al. (2011) on Climate Sensitivity - the Good, the Bad, and the Ugly
    skept.fr @50, Royer et al, 2007 has shown that climate sensitivity between 1.6 and 5.5 degrees C has been a feature of the Earth's climate for the last 540 million years. More recently, Park and Royer, 2011 refines that result. As they state in their abstract:
    "As a result, our experiment maintains an agreement with ΔT2x estimates based on numerical climate models and late Cenozoic paleoclimate. For a climate sensitivity ΔT2x that is uniform throughout the Phanerozoic, the most probable value is 3° to 4 °C. GEOCARBSULF fits the proxy-CO2 data equally well, and with far more parameter choices, if ΔT2x is amplified by at least a factor of two during the glacial intervals of the Paleozoic (260-340 Ma) and Cenozoic (0-40 Ma), relative to non-glacial intervals of Earth history. For glacial amplification of two, the empirical PDFs for glacial climate sensitivity predict ΔT2x(g)>2.0 °C with ∼99 percent probability, ΔT2x(g)>3.4 °C with ∼95 percent probability, and ΔT2x(g)>4.4 °C with ∼90 percent probability. The most probable values are ΔT2x(g) = 6° to 8 °C. This result supports the notion that the response of Earth's present-day surface temperature will be amplified by the millennial and longer-term waxing and waning of ice sheets."
    Note that they are discussing the slow-feedback climate sensitivity, ie, the climate sensitivity with the Earth is allowed to adjust by changes of vegetation, and the melting of ice sheets etc. In contrast Schmittner et al discuss fast-feedback climate sensitivity. For comparison, Hansen has recently found a fast-feedback climate sensitivity of 2.8 degrees C per doubling, and a slow feedback climate sensitivity of 6 degrees C per doubling of CO2. Applying the same ratio to Schmittner et al' fast-feedback climate sensitivity from their best fitting model (2.4 degrees C per doubling of CO2) would yield a slow-feedback climate sensitivity of 5.14 degrees C per doubling. Most of the response of the slow-feedback climate sensitivity is due to melting ice sheets, so that in non-glacial worlds the slow and fast feedback sensitivities approximately equal each other (best estimate 3 to 4 degrees C ). Applying Hansen's ratio to the glacial slow-feedback sensitivity suggests a glacial fast-feedback as derived from Park and Royer in the range of 2.8 to 3.7 degrees C. That is a little rough, of course, but suggests that slow-feedback climate sensitivities are approximately constant across a wide range of geographical configurations and temperature ranges. To that it should be added that in discussing Schmittner et al, Real Climate report that Hargreaves and Annan find model simulations of the LGM show short-feedback climate sensitivity that is 80-90% of that found for a doubling of CO2 from preindustrial conditions across a range of models. So, some difference, but small. More importantly, and as discussed in my post @48, because the equilibrium warming ratio is a consequence of evaporation, either directly, or due to increased humidity and hence reduced lapse rates, in a cooler world (and hence a world with less evaporation) we would expect the warming ratio to be smaller. Indeed, there is some evidence of this in Sutton et al, 2007 which show the warming ration declining to 1 near the poles in models, and (less clearly) in observations. Hence, while I do think there will be some change in the Warming ratio in the LGM, it will be in a direction that makes my point (1) above more significant, and my point (2) above less significant.
  32. Peter Hadfield addresses the recent email release
    Yes, I love how he once again highlights how so-called "skeptics" will swallow every piece of nonsense they read on the internet *without* bothering to double-check the validity of the claims-the exact *opposite* of a genuine skeptic.
  33. Schmittner et al. (2011) on Climate Sensitivity - the Good, the Bad, and the Ugly
    #48 Tom : on Real Climate, I read : The first thing that must be recognized regarding all studies of this type is that it is unclear to what extent behavior in the LGM is a reliable guide to how much it will warm when CO2 is increased from its pre-industrial value. The LGM was a very different world than the present, involving considerable expansions of sea ice, massive Northern Hemisphere land ice sheets, geographically inhomogeneous dust radiative forcing, and a different ocean circulation. The relative contributions of the various feedbacks that make up climate sensitivity need not be the same going back to the LGM as in a world warming relative to the pre-industrial climate. Sutton et al 2007 examined what the IPCC AR4 models give for land/ocean equilibrium change from our current temperate climate, not from glacial initial conditions. So I think their land/ocean ratio must not necessarily be used as a robust benchmark for LGM/Holocene transition. In other word, it is suggested (in the RC quote) that climate sensitivity for a doubling C02 (as well as local/global signatures of this doubling) should not be seen as a constant for the different climates of our planet over time.
  34. We're coming out of the Little Ice Age
    Stefaan, I understand your point but as I understand it, the argument regarding the LIA is more like "there is a normal temperature given the environment - there was an exceptionnal reason to change it - the reason is gone - therefore it goes back to the normal temperature". which doesn't seems so wrong in theory. Still I am no scientist. Nevertheless you don't always need to be one to take good decisions. I know that a man can die if he stays in a confined environnement with a car's engine on. It sufficient for me to believe that it's not a good idea to have millions of cars on earth without evidence of the absence of effect.
  35. Climate Solutions by Daniel Bailey
    There are more significant changes that can be made culturally and in legislation. 1. Build infrastructure that puts businesses closer to homes. Build communities where it is natural to walk and cycle etc. and the car is not seen as being essential. 2. Legislate for all new homes to be built to use the minimum amount of energy. This would depend on the location globally, but passive home design is a proven idea that works.
  36. Climate Solutions by Daniel Bailey
    uuurgh don't like vinyl windows. There is a Scandanavian company that makes soft wood/aluminium combo triple glazed windows which would be my preference. Not that it would make any difference in the UK, where many old houses are abused with fitted plastic windows and other plastic building materials.
  37. Antarctica is gaining ice
    Is there a possibility that the earth's axis has moved marginally i.e the North Pole is now slighty closer to the sun thus warmer there but colder in the south creating more ice in the Antartic. Wouldn't this also explain the changes in the magnetic fields that some scientists have apparenty noticed? i do believe that the recent earthquakes in Japan were strong enough to move the axis of the Earth albeit a small amount.
    Moderator Response:

    [DB] If you think about this you'll be able to answer your own question.  Any astronomer in the world can tell you that there's no evidence whatsoever for it.  GPS systems would be way off.  The tides would be different.  Satellites that measure earth changes to sub-millimeter accuracy would also provide evidence against it.  There is simply no physical evidence to cause such a shift that would not also be felt the world over.

    The crustal displacement/polar wander fancies of Hapgood are just that: flights of imagination.

  38. Peter Hadfield addresses the recent email release
    Oh, how I wish I could get my local State MP to watch this video. She is a perfectly nice person who is, for some reason, a rabid denier - not a sceptic, sadly, or I would send her the link in hope that she would watch it. A great video and I thank you for putting it up here. I, too, have not read the original emails, so it is nice to now have some context.
  39. It's the sun
    If you would like to contact John Cook, he can provide you with my complete 'proof',otherwise it is available from dongaddes93@gmail.com (-snip-)
    Response:

    [DB] Moderation complaints snipped.

  40. Sudden_Disillusion at 18:29 PM on 30 November 2011
    The Debunking Handbook: now freely available for download
    Great work! Keep it up. This site has become my no.1 reference for trouncing "skeptics". Klimafakten.de will help even more as my target audience speaks German mostly. cheers
  41. GHG emission mitigation solutions - a challenge for the Right?
    [ snip ] And why was my original comments not included here? It was evident that it was here for a while as comment #149 quoted some of my original comments. I'm not sure where to post this current comment since, at first, you told me to go here and now I'm told to go elsewhere. snip this commment where you must but tell me where to post this and I will.
    Moderator Response: On your original comment I responded that it was off topic, and I left it up for a while so you could see that response. Relevant threads are pointed out by KR and a moderator in #149 and #150, and Philippe in #152.
  42. Schmittner et al. (2011) on Climate Sensitivity - the Good, the Bad, and the Ugly
    Dr. Schmittner:
    "Your model is very simple dT=a*dF,but it still is a model. One that, in fact, assumes climate is in equilibrium all the time. Remember a is the "equilibrium climate sensitivity". So you model overestimates the transient temperature changes because it neglects ocean heat uptake."
    I respectfully disagree with your latter point. Please see the Figure 4 caption, which explains that I used an (admittedly very simple) estimated transient climate sensitivity parameter to create the figure. Fair point that it is indeed a model, and a very simple one, but it's a transient model, not an equilibrium model.
  43. Climate Solutions by Daniel Bailey
    Widespread degradation and deepening scarcity of land and water resources have placed a number of key food production systems around the globe at risk, posing a profound challenge to the task of feeding a world population expected to reach 9 billion people by 2050, according to a new FAO report published today. The report, “State of the World’s Land and Water Resources for Food and Agriculture” notes that while the last 50 years witnessed a notable increase in food production, “in too many places, achievements have been associated with management practices that have degraded the land and water systems upon which food production depends.” Source: “Scarcity and degradation of land and water: growing threat to food security” Food and Agriculture Organization of the United Nations news release, Nov 28, 2011 To access the entire news release, click here.
  44. Schmittner et al. (2011) on Climate Sensitivity - the Good, the Bad, and the Ugly
    Andreas Schmittner @39, I'll join with others in thanking you for the time you are taking in responding here. Please do not think that we are trying to savage or unfairly criticize your paper. On the contrary, we think it a good paper. We believe the inaccuracy in the conclusion, if any, is due to the limitations of using only one model (due to budget constraints) and any limitations in the data used (inevitable with paleo-reconstructions) and do not reflect poorly on the authors in any way. In view of some responses you have received, I believe that deserves mention. Unfortunately, we are compelled to dispel the many myths propagated by fake "skeptics" of climate science, who have seized on aspects of your paper and distorted it through no fault of your own. As such our discussion focuses on those areas of your paper which can be so distorted rather than providing the more balanced assessment which in other contexts we would like to give, and which your paper deserves. In particular, we feel it necessary to show the reasons why your paper should not be treated as the last word on a complicated subject in a rush to conclude that climate sensitivity is low, and that climate change is not a problem. (When I say "we" above, it is because I believe I capture the sentiment of most SkS authors including Dana, although strictly I speak only for myself.) Having said that, I turn again to the particular point which I have focused on in comments. I thank you for your correction of my initial confusion about the difference in equilibrium response over land and sea. As you will see above, however, Pauls had already directed me to Sutton et al, 2007, and I had corrected my critique accordingly at 21:37 PM of the 28th. Discussion on Real Climate has further elucidated the issue for me. As I understand it now, there are two overlapping issues: 1) In your paper you state:
    "The model provides data constrained estimates of global mean (including grid points not covered by data) cooling of near surface air temperatures ΔSATLGM = –3.0 K (60% probability range [–2.1, –3.3], 90% [–1.7, –3.7]) and sea surface temperatures ΔSSTLGM = –1.7±1 K (60% [–1.1, –1.8], 90% [–0.9, –2.1]) during the LGM (including an increase of marine sea and air temperatures of 0.3 K and 0.47 K, respectively, due to 120 m sea-level lowering; otherwise ΔSATLGM = –3.3 K, ΔSSTLGM = –2.0 K)."
    As noted in my earlier post, this represents a warming ratio of approx. 1.76 and 1.65 respectively. Using the 1.65 value as being the most conservative, this is significantly higher than the mean of equilibrium warming ratios found in models by Sutton et al. Indeed, it is 2.46 standard deviations higher, so the disparity is statistically significant. This strongly suggest that either your sea surface temperatures are two warm, or your land temperatures are too cold, or both. If in fact it is the sea surface temperatures that are found to be in need of adjustment, then your climate sensitivity estimate will rise. If, on the other hand, it is the land surface temperature that needs adjustment, there will be little change to your estimate in that the sea surface temperature is already strongly weighted. Given this, I note that your reconstructed data shows areas of ocean north of Iceland as being warmer during the LGM than currently, which is counter intuitive to say the least. On that basis, I suspect it is the sea surface temperature which is in error so I expect an adjustment up. I further note that because the equilibrium warming ratio is driven by differences in evaporation rates and/or humidity effects on lapse rates, the equilibrium warming ratio would be expected to decline with colder temperatures so that the above discussion underestimates the discrepancy. 2) You also state that:
    "The ratio between land and sea temperature change in the best-fitting model is 1.2, which is lower than the modern ratio of 1.5 found in observations and modeling studies (19)."
    Note that the warming ration of 1.5 is for transient values, not the equilibrium warming ratio which I believe to be more appropriate for comparison with LGM values. Regardless, that the UVic model gives a low warming ratio is unsurprising in that it poorly models the hydrological cycle and lapse rate changes. More importantly, a low warming ratio in the model would explain a significant part of the small overlap between ocean and land probability density functions of the estimate of climate sensitivity. To some extent it appears then, that the spread in PDF's between land and ocean is partly the consequence of limitations in the data. To the extent that is true, and given that the UVic model handles the hydrological cycle better over sea than over land, this supports the heavier weight given to the ocean value and a low sensitivity. The upshot is that while I think there is significant reason to believe the sensitivity is higher than that you which you found (1), that conclusion clearly does not automatically follow. I would greatly appreciate your comments on these two points.
    Moderator Response: [Sph] Requested correction applied.
  45. Climate Solutions by Daniel Bailey
    ...or more generally, Greg Craven's "You do: everything you can to increase public demand for significant and immediate policy action to combat global climate change. (Here’s the part where you get creative)"
  46. Climate Solutions by Daniel Bailey
    Daniel Bailey, thank you for the work you do at SkS. And that's an excellent summing-up, at end of this post. From my "quotes" file (to which I've added your "we will be judged...") - === As Bill McKibben says: “The number one thing is to organize politically; number two, do some political organizing; number three, get together with your neighbors and organize; and then if you have energy left over from all of that, change the light bulb.” ===
  47. AndreasSchmittner at 15:04 PM on 30 November 2011
    Schmittner et al. (2011) on Climate Sensitivity - the Good, the Bad, and the Ugly
    dana: you are using a model. Your model is very simple dT=a*dF,but it still is a model. One that, in fact, assumes climate is in equilibrium all the time. Remember a is the "equilibrium climate sensitivity". So you model overestimates the transient temperature changes because it neglects ocean heat uptake.
  48. Climate Solutions by Daniel Bailey
    Mercury bioaccumulates. Dead CFL's must be properly recycled which I don't see that happening much. LED's prices have been plummeting. From one specimen two years ago, I see 10-15 types at hardware stores.
  49. Climate Solutions by Daniel Bailey
    mandas, you're probably right. Though at the moment the gazillion cubic metres of straw/mulch and the gigantic bags of chook/cow/other poo we're bringing in to create something resembling soil here makes me think our first vegetable crops will represent a huge carbon investment. Lugging a trailer around does horrible things to fuel consumption. But it is an investment. Now that the 4m by 1m heap of potato crop (in straw and other goodies) is nearing maturity, even if the potatoes aren't that impressive, we'll also have a good crop of earthworms. (I'm not that desperate for protein, so they're going to keep on improving the soil for further crops.) I expect we won't be vegetarian but more like potatomatocapsicarian looking at what the garden's doing. And of course, there's what to do with zucchinis. Buying a freezer to store a chocolate-zucchini-cake mountain doesn't seem very sensible - but there are limits to how many zucchinis family and neighbours are willing to take on after weeks of gritting their teeth and smiling at you. The obvious solution is chooks. But they'll have to wait until sheds and tanks are done. As for people who don't grow their own, I think council waste collection systems that provide separate containers for food waste along with other compostables might get a few people rethinking their food purchases. They can actually see the volume of their 'waste' and maybe even compare it to the volume of their shopping. And reframing sell-by and use-by dating on many products would also cut down a lot of unnecessary discarding of perfectly good food.
  50. Peter Hadfield addresses the recent email release
    It is interesting to note that Hadfield's style in the Youtube piece is entirely consistant with the Debunker's Handbook. A clear and simple message has been expressed with straightforward clarity. Thanks for posting it Rob.

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