• A proxy on all your houses

    As a result of my following the Michael Mann/Mark Steyn case (well, cases nowI’ve found myself arguing with a rather tough-minded reader in the comments section.  You can see the whole thing over in my “How to Argue LIKE STALIN” post.  One of the things my reader put me onto was the following report from the University of East Anglia, about the Climate Research Unit, in which it says the following:

    CRU publications repeatedly emphasize the discrepancy between instrumental and tree-based proxy reconstructions of  temperature during the late 20th century, but presentations of this work by the IPCC and others have sometimes neglected to highlight this issue.

    Got that?  CRU scientists have been pointing out, repeatedly, that proxy reconstructions (the hockeystick) are not as solid as all that, but the IPCC has been known to ‘neglect to highlight’ this point.

    One thing I have been saying for some time is that there is a yawning chasm between what the science says and what the popular press says.  Now please look at that comment again.  If even the IPCC is simplifying things – how much worse is the case in the popular media?

    When was the last time you read an article in the popular media that even mentioned that we are still quite unsure as to what the exact climate of past centuries was?  Plenty of scientists acknowledge this basic point, and have said so in print in the best scientific journals there are – but when was the last time the Guardian or the New York Times mentioned this point?

    This is why so many people think the whole thing is nonsense – they are being fed a false and hyped image of what is actually going on.

    Category: APGW

    Article by: The Prussian

    • Jim

      Of course there is uncertainty about the Earth’s past climate, but we do know that the Earth’s climate has changed dramatically over the millennia from Ice ages that covered half the globe to warm tropical climates – all without any input from Man. Natural climate variability is driven by variations in solar output, Earths orbit and inclination relative to the Sun, changes in tidal and oceanic currents, plate-tectonic motion, and other natural causes. The additional CO2 added by burning fossil fuels is a second order effect at best, and is not primarily responsible for climate change.
      The biggest harm being done by the climate charlatan’s is that real research into the primary drivers of climate is being neglected or ignored; and their solution of global energy control/rationing is harmful to humans who want the freedom to pursue a better life.

      • josh

        “Natural climate variability is driven by variations in solar output,
        Earths orbit and inclination relative to the Sun, changes in tidal and
        oceanic currents, plate-tectonic motion, and other natural causes.”

        You neglect to mention that feedback effects from capture/release of CO2 also play a role in past climate change. But ‘past’ is the key word here. The current climate change appears to be driven by human-released CO2. I’m not sure why this should be a difficult point. Compare: past mass extinctions were caused by meteor strikes, rapid climate change, and other natural causes. The current mass extinction appears to be driven by humans.

        There is also a question of time scales. Ice ages occur on scales of ~100,000 years, not the decades and centuries that concern humans. Look at it this way: the sun will expand and consume the Earth in 4 billion years or so. That does not mean that we can ignore what happens in the meantime, or that the consumption of the sun’s fuel is the ‘primary driver of climate’ on relevant time scales.

        • Chic Bowdrie

          Josh, Jim may have neglected feedbacks because of the question about the sign, let alone magnitude, of those effects currently under investigation by climate scientists. Climate change “appears” to be driven by CO2 (regardless of the source) by some, but a strong case has been made recently for temperature driving CO2. Prudence suggests we wait until science has a chance to sort these things out before we start talking about extinctions.

          • josh

            Hi Chic,
            Prudence would suggest that if there is a threat of (even more) extinctions we should be risk averse, no? Like buying house insurance even if you aren’t 100% sure that your house is on fire. About the sign, I don’t know of any serious argument that CO2 is not a positive feedback. The greenhouse effect isn’t really in doubt.

            I’m not sure what you’re referring too about a ‘strong case’ for temperatures driving CO2. Again, this distinction about the past and the present is important. As the globe warms, more CO2 from natural sources is released, this in turn tends to raise global temps. It’s a positive feedback. In past warming events it may well be that another factor first started raising temps, but CO2 is an important part of the total warming, to the best of my knowledge. In the current situation, we still have to worry about that natural CO2 release, but we have a major additional source from humans, and we know with useful certainty how much we are generating. That generation accounts for observed warming which cannot be accounted for from natural sources. And the problem is that on long time scales the net effect of that anthropogenic warming, multiplied by the net feedback effect, is a major shift in global climate.

            The science on this won’t stop and we can look forward to better estimates of magnitudes in the future, but that doesn’t imply that we can ignore what we know now: warming is happening, it is primarily caused by humans and the future magnitude is significant enough to be seriously worried.

            • Chic Bowdrie

              Josh,

              The planet is not a greenhouse. If you mean IR absorbing gases contribute to a moderate climate, well of course I agree. However, positive feedbacks are disputed by the failure of climate models to match observations and the current research of some prominent climate scientists.

              The best of your knowledge is basically the unsubstantiated hypothesis that humans contribute the majority of increasing CO2 thus warming the planet as much as 3 degC for 2xCO2 and your assertion that natural causes cannot otherwise account for over a century of less than 1 deg of warming.

              I agree with you that climate science will improve, but doubt it will confirm your prognostications. Murray Salby has a provocative presentation that disputes some of the central tenets of AGW doctrine you described. He makes a very strong case for temperature driving CO2 and NOT vice versa. http://hockeyschtick.blogspot.com/2013/06/climate-scientist-dr-murry-salby.html

            • josh

              Hi again Chic,
              “The planet is not a greenhouse. If you mean IR absorbing gases contribute to a moderate climate, well of course I agree.”

              The greenhouse effect refers to an increased concentration of IR absorbing gases leading to a higher equilibrium temperature.

              “However, positive feedbacks are disputed by the failure of climate models to match observations and the current research of some prominent climate scientists.”

              There are positive and negative feedback mechanisms. All the data points to the net effect in our current conditions being positive. Climate models predict a long term positive trend in temperatures, which is what we observe. Models don’t perfectly predict short term trends that depend on things like the heat exchange cycle between the ocean and the atmosphere. But this doesn’t invalidate the general agreement between models and observation.

              “The best of your knowledge is basically the unsubstantiated hypothesis
              that humans contribute the majority of increasing CO2 thus warming the
              planet as much as 3 degC for 2xCO2 and your assertion that natural
              causes cannot otherwise account for over a century of less than 1 deg of
              warming.”

              It’s not the “best of my knowledge” and “[my] assertion”, it is the best estimate of the body of experts whose job it is to understand these things. It’s not an unsubstantiated hypothesis, it is a theory based on experimental results.

              I took a look at the link you posted and I have to say it looks like a bunch of fallacies. The first slide, which incorrectly labels rate of emission as ‘net emission’, actually seems to show that rate of CO2 emission leads temperature swings. But these are swings on a yearly timescale almost, which may correlate with all sorts of things. What they don’t do is somehow disprove the accepted theories of global warming.

              His main schtick seems to be the idea that natural CO2 emissions are quite large compared to anthropogenic ones. But this isn’t news and it’s a red herring. What matters is the balance between emission and absorption, and how humans have shifted that through fossil fuel burning. He claims ‘climate model predictions track only a single independent variable – CO2 – and disregard all the other [variables]…’ Which is patently false. Climate models include water vapor, methane, aerosols, volcanic eruptions, sun intensity, albedo, ocean salinity, etc. etc. etc.

            • Chic Bowdrie

              Josh, aside from it being a misnomer, the problem with greenhouse
              verbiage is it reduces the complex physics of the atmosphere to an oversimplified misleading model. Quantifying the effect of additional CO2 in the atmosphere on the global temperatures is quite a different issue than recognizing that only a sufficient amount of IR absorbing gases is required to establish a relatively narrow range of global temperatures varying around a temperate mean compared to an atmosphere without IR absorbing gases. Climate models fail to quantitate that effect and I don’t see how you can say it “is what we observe.” The general agreement that you imagine with the models is a hindcast achieved by introducing enough adjustable parameters to obtain a reasonable model fit. The failure of the models to forecast correctly is evidence that the model is flawed either because of incorrect parameters, exclusion of factors, or both. You can assert what experts say and cite their results, but that doesn’t make the hypothesis proven or the theory valid.

              I compliment you for viewing Salby’s presentation. If you see fallacies, then maybe go over it again as I have had to do. He is showing data that highly correlates temperature with the derivative of CO2 with a lag time of about 10 months. Satellite measurements show local CO2 increases in rural forested areas, as opposed to urban areas, which could be explained by temperature affects on vegetation. As you point out, these natural sources of CO2 emissions overwhelm anthropogenic ones. This is strong evidence that CO2, regardless of its source, is not determining global temperatures. His assertion that model predictions track only CO2 is essentially saying that CO2 is the predominant contribution to the trajectory of future temperatures and that this is not reality.

              Neither Salby’s talk nor any computer modeling has definitively determined the magnitude of the effect CO2 has on temperature. That research remains to be unveiled. What his research does show is that man’s influence on global temperatures may be minimal.

            • josh

              Whether you approve of the name is really irrelevant. Of course climate models quantify the size of the greenhouse effect! Otherwise there would be no basis for saying that they do or don’t agree with predictions. Like all scientific quantities they have error bars which is why you get a distribution that looks something like between 1.5 and 4.5 degrees C for climate sensitivity. The change in actual temperature then depends on the change in radiative forcing, which is calculated for CO2 and other gasses, as well as changes in solar irradiance, albedo, etc.

              “The general agreement that you imagine with the models is a hindcast achieved by introducing enough adjustable parameters to obtain a reasonable model fit.”

              No, although some ‘skeptics’ take this approach of adding parameters to do short term fits. In real climate models all the parameters reflect actual physical properties which you have to go out and measure, they aren’t just added in (or ignored) for convenience. To test a model, since we can’t just wait 100 years on the relevant questions, you start with the best estimates of those parameters at some historical period and compare the model with the actual record. What else could you possibly do? And the key point is that this works, BUT for the modern period if you don’t include the anthropogenic CO2 you don’t reproduce the observed temperature increase. That is precisely not a case of introducing parameters to get a fit.

              Now, no model will ever be perfect and there will always be deviations between the model and reality at some level. For the models we’re talking about there are dynamics like ocean-air, ENSO type interactions that are far from perfectly modeled. Thus, while models DO predict decade-plus periods of small change in the surface temperature (we continue to observe ocean heating), they aren’t sufficient to forecast exactly when they will stop and start. That doesn’t negate the long term trend predicted or observed. Think of it like a casino: I can predict your long term winnings if I know the rules of the game, and I can predict that hot and cold streaks are likely, but I can’t say if the next few rolls of the dice will be lucky.

              “This is strong evidence that CO2, regardless of its source, is not determining global temperatures”

              You’re hung up on a fallacy here. Global temperature is determined by a combination of factors, not least of which is the existence of the sun! But what is relevant to the discussion is how that temp will change in response to changes in the factors we can track. In terms of the near future (multi-decade to centuries) the dominant factor in the change is man-made CO2. Of course if the sun radically altered it’s behavior, or the biomass collapsed, or we had massive volcanic eruptions that would also alter the temp, possibly overwhelming the CO2. But we don’t have reason to think any of those things will happen and we do know CO2 is only going to increase on the current path.

              Salby is ‘discovering’ the fact, known long ago by climate scientists, that plants produce CO2 and respond to temperature. You also have outgassing and absorption by the ocean. These produce big annual swings in atmospheric CO2. But the question is what happens in the long run. The swings balance out to almost zero and the human contribution is what’s left over to pile up over time. In fact, as humans add to the overabundance of atmospheric CO2, nature is absorbing more than it normally would. Thus we have, e.g., a measurable increase in ocean acidification. Rather than Salby, who is not an expert in this area, why not go to the actual experts to find out how they do attribution?

            • Chic Bowdrie

              Yes, my approval of greenhouse terminology is irrelevant, but can you understand why I dislike using a greenhouse as a climate analogy? A greenhouse is relatively warm and the atmosphere is relatively warm. That’s all they have in common. Most everyone recognizes the greenhouse effect is the result of IR absorbing gases in the atmosphere. But temperature sensitivity to changes in the composition of the gases is another matter. The effect of doubling CO2 (or any nominal increase) is an alleged enhancement of this so-called poorly named greenhouse effect. No one knows for sure what the magnitude of the CO2 effect is. There are no measurements with which error bars can be associated. All you have is computer modeling based on a hypothesis that has yet to be verified by experimental data. As you admit, we can’t do a 100 year experiment. Neither can we inject 100 ppm more CO2 now. But a model has to be tested at some point against data. Hind-casting is not testing. And comparing model predictions with the actual record has NOT worked! The models call for increasing temperatures, but have flat-lined going on two decades now.
              Either some factors have much more influence than expected or CO2 has much lower sensitivity than previously supposed.

              “But what is relevant to the discussion is how that temp will change in response to changes in the factors we can track.”

              How do we track factors that are as yet unknown or not adequately understood? You dismiss current research indicating the involvement of the sun, clouds, oceans and then assert without proof that man-made CO2, let alone CO2 from whatever source, is the dominant factor controlling temperature change. That doesn’t make sense to me.

              Plants consume CO2 when growing and produce CO2 when decaying which Salby proposes happens in response to temperature and soil moisture. Oceans produce and out-gas CO2 also in response to temperature. Salby estimates the natural emissions are as much as thirty times human emissions. Believing
              human emissions make up all of the increased CO2 requires believing no net natural emissions were due to the 1 degC temperature rise in the past century. Does that make sense to you?

            • josh

              I’m not sure why you object so strongly to the term greenhouse effect. I’m aware that conservatories work mostly by preventing convection but they make for a simple picture when explaining how different wavelengths of light can be more or less transmitted.

              Anyhow, you say ‘No one knows for sure what the magnitude of the CO2 effect is.’ Which is trivially true. No one knows for sure what the charge of an electron is either, we only know what the measurements tell us within error bars, in the context of a consistent theory. The error bars are larger in the case of the greenhouse effect, but you seem to equate that with ‘completely unknown’, which isn’t the case. I’m not sure what measurements you think we aren’t doing. We measure temperatures, we measure radiation at different wavelengths, we measure CO2 content, and where it comes from…

              You say a model has to be tested against data, that is exactly what is done, that’s what hind-casting is. But you want to rule that out for some reason. Do you also rule out scientific theories of cosmology, of evolution, of geology? Is plate tectonics just a guess until we wait 50 million years? You then change tactics and say that models do make predictions but that they are falsified, and this also is not true. The models make predictions and the observations are consistent within the margin of error. You say that temps have ‘flatlined’ but actually they have jumped all around, which means you are looking at short term noise. If you take the short term trend you get something relatively flat, but the model prediction is for the long term trend, which remains consistent. Are there models that claim they can predict the climate over a single decade with small errors? If so they may well be falsified but that’s not the model claim the IPCC is talking about.

              I think I already said this, but one thing that isn’t well modeled is ENSO-type oscillations that can have large effects on the short term. Not that we can’t see similar things in climate models, but that getting the timing right is beyond our current best efforts. But that doesn’t mean they can cancel out long term trends. It’s like predicting when a thunder storm will occur months ahead of time vs predicting that summer will be hot months ahead of time.

              “How do we track factors that are as yet unknown or not adequately understood?”
              We look at the upper limit on how big those effects could be from past data, from basic physics, etc. We have experts whose job it is to determine what factors are important, what are unknown and what can be reasonably ignored, same as in any science.

              “You dismiss current research indicating the involvement of the sun,
              clouds, oceans and then assert without proof that man-made CO2, let
              alone CO2 from whatever source, is the dominant factor controlling
              temperature change.”

              No, I point out that climate research takes into account current research on clouds, oceans, the sun etc. And the picture which emerges is that CO2 is the dominant factor on the time-scales we care about. I’m not asserting this without proof, I’m telling you that’s what the research says. If you really want all the gory details then go through the reams of research put out by the climate community.

              “Believing human emissions make up all of the increased CO2 requires
              believing no net natural emissions were due to the 1 degC temperature
              rise in the past century. Does that make sense to you?”

              The IEA estimates human emissions from fossil fuel burning. We emit around 30GT per year. About half of that is absorbed by nature and the rest goes into the atmospheric excess. The oceans are absorbing more, not emitting more. The rise in atmospheric CO2 is less than the amount emitted by humans. There is a net natural absorption.

            • Chic Bowdrie

              Hi Josh,

              The charge of an electron is 1.602 x 10-19 coulombs. We can estimate the error of the measurements that resulted in that figure by assuming the last digit is significant. The point is there were actual measurements involved. How much CO2 will raise temperature has never been measured directly. What has been done is taking a spectrum captured from a satellite years ago and comparing it with a recent spectrum. Computer programs like Modtran or Hitran convert differences in the absorption bands to energy values assumed to cause an energy imbalance or “forcing”. The forcing is associated with temperature according to a sensitivity scaling factor. This method has not been validated and since these calculations are not actual measurements, the error bars are just as much an estimate as the most likely value of the sensitivity.

              “You say a model has to be tested against data, that is exactly what is done, that’s what hind-casting is.”

              No, hind-casting is fitting a model to data. The testing comes by doing further experiments to see if the model holds up. In the climate case this means more time points in the future. GCM models predict steadily rising temperatures, but the temperatures have jumped all around a mean that has remained the same for arguably 18 years or so. I don’t want to quibble over terminology so I apologize for erroneously describing it as flatlined. You can dismiss this discrepancy by saying it is within the margin of error. I prefer to look at the other factors that are the likely cause of the discrepancy.

              “We look at the upper limit on how big those effects could be ….”

              How can you trust an upper limit on a factor you don’t understand?The cloud feedback is arguably net negative. Putting an upper limit on it as a positive feedback is meaningless. Also, suggesting we should leave the evaluation of relevant factors to the experts is not a very convincing argument. Who decides who is expert? Many I would call experts are challenging your conventional views, particularly the one that claims CO2 is the dominant factor.

              30Gt of CO2 emissions with 50% absorbed per year corresponds to a yearly increase of 2ppm CO2 which is about right. So I repeat does it make sense that all of that increase is due to humans when natural emissions are 20 times greater than human emissions? How do you know natural emissions are not increasing due to the rise in global temperatures?

            • josh

              Hi Chic,
              Error bars always involve a degree of estimation, otherwise we would know the exact answer. I still don’t know why you won’t acknowledge the actual measurements that are made. Satellite readings of spectra are measurements, temperature readings on land and sea are measurements, the absorptions behavior of CO2 in a lab is a measurement. All these things require codes and calibrations and theory to correlate, which is true for any modern science. You say these things haven’t been validated but that’s because you refuse to acknowledge the method of validation.

              Hind-casting isn’t the same a model fitting. In a hind-cast you take a given model, start it with the parameters of a particular time (CO2 levels, current temps, volcanic eruptions and aerosols, solar output, etc.) and let it run from that point. The test is whether the model can reproduce the historical record from that point. Now this is an iterative process of course, if the models don’t pass the test then you have to go back and refine them. But again, this is how science normally works. As far as predictions, the models predicted we would see global warming and we have.

              You object that models predict steadily warming temperatures but I don’t believe this is accurate. An individual model run will produce a jagged prediction that can include decadal pauses. What is usually presented as the prediction is an average over many model runs and multiple models. This shows a smoothed increasing trend but it would only be a fair comparison if you had multiple earths to average over.
              If you want to look at factors that cause short term discrepancy, well, so are the climate modelers. But that doesn’t invalidate the long term prediction or make the models garbage.

              “How can you trust an upper limit on a factor you don’t understand?The
              cloud feedback is arguably net negative. Putting an upper limit on it
              as a positive feedback is meaningless.” An upper limit on magnitude. If clouds are a net negative they can’t be such a big effect that they would invalidate past observations (or they would require a similarly large positive feedback from another source to account for the overall net behavior).

              “Who decides who is expert?” Well, for starters I would go with the majority of professors and postdocs who work in the field. But you can also evaluate the quality of argument offered by the different sides. When I go to a prominent skeptic, like Salby, and I can immediately recognize fallacies in his presentation I am wary. And then when I read the response from the consensus position and I get technical details as well as perspective, I can judge who knows what they are talking about.

              “How do you know natural emissions are not increasing due to the rise in global temperatures?”
              If only half of human emissions account for the observed increase in CO2, then their must be a net absorption from natural sources, no?

            • Chic Bowdrie

              Josh, I never said the models are garbage. I said they are wrong either because some factors are missing or miss-handled or the CO2 sensitivity is too large. I don’t understand your explanation of how hind casting works. What is the reference point you refer to? If your test is whether a model tuned to fit the temperature record prior to that reference point can reproduce the temperature record from that point on, then can you explain why the vast majority of climate models have and continue to over-predict global temperatures? http://www.drroyspencer.com/2014/02/95-of-climate-models-agree-the-observations-must-be-wrong/ In no way does this confirm CO2 as a dominant factor. Would you agree, if future temperatures fail to increase or even decrease, the reason might be that CO2 sensitivity is too large?

              “An upper limit on magnitude. If clouds are a net negative they can’t be such a big effect that they would invalidate past observations (or they would require a similarly large positive feedback from another source to account for the overall net behavior).”

              Not if the overall net behavior, ie surface temperature increase, is overrated. The big picture is that clouds, sun, and ocean are not well understood and the models reflect that.

              I don’t agree that you identified fallacies in Salby’s work. You say you can judge who knows what they are talking about. Are you an expert?

              All you are saying about emissions is that the sinks are absorbing more than the total sources. That does not preclude that natural sources are growing due to increasing global temperatures and soil hydration. You can see this in the satellite data shown in Salby’s presentation. So increases in natural sources of CO2 could be conflated with human sources.

            • Chic Bowdrie

              Where is the validation procedure for predicting the temperature rise due to an incremental increase in atmospheric CO2?

            • WFC

              Some questions:

              (A) which models do you say forecasted 21st century temperatures?
              (B) which models can even hind cast 21st century temperatures?
              (C) if the surplus energy is going into the oceans (deep or otherwise) how is it ever going to emerge, undiluted, from those oceans?

            • josh

              (A),(B) http://www.skepticalscience.com/contary-to-contrarians-ipcc-temp-projections-accurate.html

              (C) What do you mean undiluted? If the excess energy in the oceans suddenly was converted into an air temperature excess it would be catastrophic. In the long run excess temperature in the ocean will equilibrate with the atmosphere (on average, we’ll still have annual oscillations around the average). You can’t just raise the temperature of the oceans indefinitely while keeping the atmosphere fixed. In the long run the oceans will be warmer, the deeper water will be warmer, and the atmosphere will be warmer. (Actually the stratosphere cools, but that’s a complication for another day.)

              Of course we are out of equilibrium now and it is a dynamic process by which equilibrium is approached. One major factor in this is the El Nino-Southern Oscillation which corresponds with variations in the Pacific Ocean surface temperature and how much cold water from lower depths is welling up to the surface.

            • WFC

              But it wouldn’t be “converted into an air temperature” at the same temperature, would it?

              The amount of energy which would increase atmospheric temperatures by 1 deg would only warm sea temperatures by 0.01 degs (numbers illustrative).

              Which means that the oceans (and that energy) could only ever warm the atmosphere by 0.01 degs as the result of that additional energy.

              (That’s what I mean by “diluted”.)

            • josh

              I don’t think the ocean heat is going to suddenly pop back into the air. At the same time it is more complicated than putting two reservoirs with a .01 deg heat difference in contact and waiting for them to come to equilibrium. (Sorry if I seemed to imply that above.) The earth isn’t in equilibrium, although it can be in an approximately steady state. Heat transfer between the ocean and atmosphere happens through convection, evaporation and radiation and you can get big atmospheric effects from, e.g. El Nino.

              The point is, it is extremely unlikely that we can just continue to dump heat into the ocean with no effect on the land and sky, nor is it likely to be a good thing even if we could choose to only heat the ocean.

            • WFC

              As regards (A) and (B) I will look at you link, but I’m not a big fan of SkS.

              ISTM that going to SkS for climate science is like going to the Vatican for an impartial opinion about the existence of God.

            • josh

              Well, I appreciate you’re going to read them because they are the experts and I am not.

            • WFC

              SkS?

            • josh

              The research linked, in this case coming through the IPCC. I don’t know the people behind the website.

          • Jim
    • MikeNov

      Well these same CRU scientists were part of the IPCC. Brifa was a chapter lead author and only mentioned divergence in response to review comments from Steve McIntyre.

    • MikeNov

      Surprising revision to Pages2K. Now that IPCC has passed, it has been corrected back to a non-hockey stick.