What we know with confidence

by Judith Curry

Of the four IPCC assessment reports, I  think the first assessment report (FAR) presents the case with the greatest clarity.

Since the FAR was published 20 years ago, it is worth taking a look to see how their conclusions and levels of confidence and uncertainty have stood up to the test of time.

The FAR Summary for Policy Makers makes the following statements:

We are certain of the following:

  • there is a natural greenhouse effect which already keeps the Earth wanner than it would otherwise be
  • emissions resulting from human activities are substantially increasing the atmospheric concentrations of the greenhouse gases carbon dioxide, methane, chlorofluorocarbons (CFCs) and nitrous oxide These increases will enhance the greenhouse effect, resulting on average in an additional warming of the Earth’s surface. The main greenhouse gas, water vapour, will increase in response to global warming and further enhance it

We calculate with confidence that:

  • some gases are potentially more effective than others at changing climate, and their relative effectiveness can be estimated. Carbon dioxide has been responsible for over half the enhanced greenhouse effect in the past, and is likely to remain so in the future
  • atmospheric concentrations of the long-lived gases (carbon dioxide, nitrous oxide and the CFCs) adjust only slowly to changes in emissions. Continued emissions of these gases at present rates would commit us to increased concentrations lor centuries ahead The longer emissions continue to increase at present day rates, the greater reductions would have to be for concentrations to stabilise at a given level.
  • the long-lived gases would require immediate reductions in emissions from human activities of over 60% to stabilise their concentrations at today’s levels, methane would require a 15-20% reduction

Our judgement is that:

  • Global – mean surface air temperature has increased by 0.3°C to 0.6°C over the last 100 years, with the five global-average warmest years being in the 1980s.  Over the same period global sea level has increased by 10-20cm. These increases have not been smooth with time, nor uniform over the globe
  • The size of this warming is broadly consistent with predictions of climate models, but it is also of the same magnitude as natural climate variability Thus the observed increase could be largely due to this natural variability, alternatively this variability and other human factors could have offset a still larger human-induced greenhouse warming The unequivocal detection of the enhanced greenhouse effect from observations is not likely for a decade or more
  • There is no firm evidence that climate has become more variable over the last few decades However, with an increase in the mean temperature, episodes of high temperatures will most likely become more frequent in the future, and cold episodes less frequent

I have left off various climate model projections and a few other things that aren’t directly related to detection and attribution.

How have these statements held up over time?  Have there been any serious challenges to these statements?  Is the known ignorance associated with these statements substantial?  Are these the statements that pretty much everyone can agree with?

Is this a better way of describing the state of our understanding, relative to the  confidence and likelihood statements in the TAR, AR3?

Lets see if we can identify the common ground of agreement on the scientific basics.

390 responses to “What we know with confidence

  1. Stephen Singer

    So far in my studies across many blog sites and web sites on this issue suggest that there is still considerable debate about the life-time of CO2 in the atmosphere. So, that suggests that drastic reductions of anthropogenic CO2 are likely a solution to a non-existent problem. This is especially true since climate scientists acknowledge large uncertainty in the feedback properties of cloud cover. Read Dr. Spencer’s recent paper on cloud feedback on climate sensitivity: http://www.drroyspencer.com/wp-content/uploads/Spencer-Braswell-JGR-2010.pdf.

    • Please define what you mean by lifetime, do you mean residence time of a CO2 molecule, or the time over which an increase in the CO2 mixing ratio remains.

      They are significantly different, but people use lifetime for both.

  2. The FAR is certain of this:
    “The main greenhouse gas, water vapour, will increase in response to global warming and further enhance it [greenhouse effect]”

    The FAR calculates this with confidence:
    ” Carbon dioxide has been responsible for over half the enhanced greenhouse effect in the past, and is likely to remain so in the future”

    These juxtaposed statements say to me that the trace gas CO2 is calculated to be a more potent greenhouse enhancer than is the major greenhouse H2O gas. This is a non-sequitur, it appears. Maybe someone could show me the logic here, without arm-waving or paywalled references, please

    And what is an “enhanced greenhouse effect in the past” ? Which timescale, from when to when, how is this confidently calculated ? For that matter, “enhanced” from what assumed background ? Why is the comparitive background not assumed to be depressed, in the sense of opposite to enhanced ?

    Spence & Braswell 2010 (referenced above in Stephen Singer’s post) also contend that evaporation (from heating) is matched by precipitation (cooling). A dynamic balance, of course, not static

    • David L. Hagen

      The main greenhouse gas, water vapour, will increase in response to global warming and further enhance it.

      Roy Spencer highlights a major uncertainty is which is the cause and which the effect regarding water vapor and clouds.
      Does warming decrease clouds, or does a reduction in clouds cause warming?
      Is the change in clouds the consequence of anthropogenic CO2?
      OR do natural causes impact clouds which change warming which impacts water and CO2 concentrations?
      e.g. see Henrik Svensmark‘s growing evidence for Cosmoclimatology. e.g. evidence that solar Forbush events show up to a 7% reduction in liquid water in clouds.
      Model of optical response of marine aerosols to Forbush decreases Atmos. Chem. Phys., 10, 2765–2776, 2010

      This may have a critical impact on CO2 as cause/consequence.
      This uncertainty critically undercuts the “certainty” that “water vapour, will increase in response to global warming”, as it might be vice versa.

      This causation/consequence uncertainty equally hits:
      “And further enhance it”
      It might be the other way around.

      Until causation/consequence is sorted out regarding clouds/water/CO2/warming, we cannot be confident in these FAR pronouncements.

  3. ” Are these the statements that pretty much everyone can agree with?”

    We are certain of the following:

    ■there is a natural greenhouse effect which already keeps the Earth wanner than it would otherwise be

    So far, so good, for certainty. Though I’d have said “warmer’ in place of “wanner”. ;)

    ■emissions resulting from human activities are substantially increasing the atmospheric concentrations of the greenhouse gases carbon dioxide, methane, chlorofluorocarbons (CFCs) and nitrous oxide These increases will enhance the greenhouse effect, resulting on average in an additional warming of the Earth’s surface.The main greenhouse gas, water vapour, will increase in response to global warming and further enhance it

    This.. I’m not sure fits into the ‘certainty’ category, and would demote it to the ‘with confidence’, which I would then endorse depending on the evidence.

    We calculate with confidence that:

    ■some gases are potentially more effective than others at changing climate, and their relative effectiveness can be estimated.

    Why isn’t the above in the certainty category? It’s certainly vague enough at to be almost a tautology, and needs in itself little explicit calculation.

    Carbon dioxide has been responsible for over half the enhanced greenhouse effect in the past, and is likely to remain so in the future

    Agree with the placement of the above line, and with the confidence-level associated with it for a policy paper.

    ■atmospheric concentrations of the long-lived gases (carbon dioxide, nitrous oxide and the CFCs) adjust only slowly to changes in emissions.

    The immediately preceding line ought (now, at least) be moved into the certainty category, based on the claims of isotope studies, etc, I think.

    Continued emissions of these gases at present rates would commit us to increased concentrations lor centuries ahead

    Above line looks like it is probably placed correctly by category, though perhaps “for” for “lor”, and might specify “present projected rates”.

    The longer emissions continue to increase at present day rates, the greater reductions would have to be for concentrations to stabilise at a given level.

    I see no reason to support the above line. It assumes too much with too little support, that reductions can lead to stabilization still

    ■the long-lived gases would require immediate reductions in emissions from human activities of over 60% to stabilise their concentrations at today’s levels, methane would require a 15-20% reduction

    Wouldn’t mind reviewing the calculations and conclusions in detail, but can see this might be a possible conclusion, however I suspect much more work is needed for the above line to be described as ‘confident’.

    Our judgement is that:

    ■Global – mean surface air temperature has increased by 0.3°C to 0.6°C over the last 100 years, with the five global-average warmest years being in the 1980s. Over the same period global sea level has increased by 10-20cm. These increases have not been smooth with time, nor uniform over the globe

    Seems to fit into the ‘judgment’ category well, given the overall issues with the temperature record mentioned later.

    ■The size of this warming is broadly consistent with predictions of climate models, but it is also of the same magnitude as natural climate variability

    Kinda vague still, but sure.

    Thus the observed increase could be largely due to this natural variability, alternatively this variability and other human factors could have offset a still larger human-induced greenhouse warming

    The unequivocal detection of the enhanced greenhouse effect from observations is not likely for a decade or more

    Seems they got this at least bang on.

    ■There is no firm evidence that climate has become more variable over the last few decades

    Nor had anyone really looked too hard, so.

    However, with an increase in the mean temperature, episodes of high temperatures will most likely become more frequent in the future, and cold episodes less frequent

    Seems they got this one bang on, to.

    Do I like this approach?

    It seems too open to malicious misunderstanding, and more appropriate to a first report than a report reflecting three decades of advancement and continual improvement of methods and processis.

    • David L. Hagen

      IPCC held that:

      The size of this warming is broadly consistent with predictions of climate models, but it is also of the same magnitude as natural climate variability

      The Ptolemaic cosmic system could equally be described as “broadly consistent” with observations. So was Capernicus’ theory.
      Kepler’s key breakthrough of elliptical orbits was based on Brahe’s very accurate observations, which provided the basis to distinguish “broadly consistent” from quantitative elliptical models.

      In climate, the most accurate measurements may be the Length Of Day (LOD) variations. These are now being modeled vs solar parameters. e.g.:

      We study the evolution of the amplitude A of the semi-annual variation of the length-of-day (lod) from 1962 to 2009. We show that A is strongly modulated (up to 30%) by the 11-yr cycle monitored by the sunspot number WN. A and WN are anticorrelated, WN leading A by 1-yr. A is therefore directly correlated with galactic cosmic ray intensity. The main part of the semi-annual variation in lod is due to the variation in mean zonal winds. We conclude that variations in mean zonal winds are modulated by the solar activity cycle through variations in irradiance, solar wind or cosmic ray intensity.

      Solar forcing of the semi-annual variation of length-of-day Jean-Louis Le Mouël et al.
      GEOPHYSICAL RESEARCH LETTERS, VOL. 37, L15307, 5 PP., 2010
      doi:10.1029/2010GL043185
      That sounds a lot more quantitative than “broadly consistent”!

      • David L. Hagen

        While your points work comparing the IPCC summare to the details of your candidate, it’s a bit of comparing apple seeds to apple pie.

        A summary is meant to summarize; a summary of a broad field must in the same space as a summary of a narrow field cover many times more ground and the complex interrelations of the whole compared to just the contention of one narrow hypothesis.

        That the candidate you propose may have some sort of merit notwithstanding, a summary of all natural variability claims would be more appropriate a comparison, and it appears your own candidate would be less than a footnote to more prominent claims in such a big field.

        In comparing like to like, what you say does not satisfy.

  4. Hi Judith, thanks for opening up this discussion.

    The qualitative elements of these statements remain broadly correct, and is consistent with the 2010 National Research Council Climate Stabilization Targets reports which discusses the evidence for climate change and concludes that global warming can endure for tens of thousands of years, with concentrations remaining elevated in considerable time even after emissions have ceased and that only a fraction of warming has been realized due to time lags inherent in the Earth-system. Among other things, they also highlight issues in defining ‘temperature extremes’, with some focus on anomalously hot summers.

    Clearly the quantitative aspects of summaries such as this, such as the amount of warming ,sea level rise, etc will grow outdated as time progresses, and there is now substantial confidence in anthropogenic contribution through D&A efforts and larger radiative forcing since the FAR. Thus their is little in this post itself that has underwent serious challenge since the FAR. There are still large body of questions, such as how the El Nino Southern Oscillation will change as the climate warms, which cannot be answered with much confidence yet.

    Although your stated goal was to discuss the basics, perhaps looking for a common ground amongst people on this blog, there is no indication that any of these “key” components will change in the Ar5– rather I think this serves as a good starting point for where people discussing this issue intelligently should be at, with an emphasis on moving the disagreement toward the more subtle “non-basic” matters.

    • This is really quite simple. The second “certainty” statement is the basic claim of AGW. The CO2 increase is human, it will cause warming, which a positive water feedback will amplify. AR4 is actually weaker, having abandoned the claim of certainty.

      Skeptics in general agree with none of this, and most of the other claims as well, offering detailed counter arguments to do so. So no, there is no point of common ground here, except the out-of-place statement that the estimated warming to date might well be natural.

      Twenty years and many billions of dollars in climate research have failed to resolve these issues. Skeptics argue that this proves that the human influence is undetectable. It certainly makes the certainty claims untenable.

      • To close the circle, what we know with confidence is (1) climate changes naturally and (2) we do not yet know why. A research program awaits us. In the meantime AGW is simply premature (and unlikely given what we do know).

  5. “broadly consistent” means nothing.

    Birds singing outside my window before the sun rises is broadly consistent with the sun rising because of the birds singing.

    • John McLean

      If it makes you feel more comfortable, simply transpose the phrase “broadly consistent with,” and “of the same magnitude as.”

      ;)

      • Guys, with all due respect, Judith has written a post discussing a series of claims and ways to sift through the confidence in those claims within the confines of scientific evidence. If you’re going to make claims or counter-claims, at least provide some indication you have familiarity with the subject in question– formal D&A has never been about agreements in magnitude between models and obs for instance, and in fact could be accomplished by removing the global mean signal. Process by elimination is not very convincing (See some work by Knutti on this issue for example). Thus Bart R’s transposition is simply not right.

      • Chris Colose

        Of course the transposition wasn’t right. It was an equivalency of two similarly ambigious (and almost possible to read with the same meaning) imprecisions. It’s impossible to get it right with the words in the original quote, used in any order.

    • The comments are a summary of the research, not the research itself. If you want the reasons, they are there, in the rest of the reports, with references to the research.

  6. Willis Eschenbach

    Judith, you are aware of course that you’ll be thrown out of good company if you persist in trying to actually determine the areas of agreement and disagreement …

    Onwards to your most interesting question, point by point:

    We are certain of the following:

    • there is a natural greenhouse effect which already keeps the Earth wanner than it would otherwise be

    I would agree that this is certain.

    • emissions resulting from human activities are substantially increasing the atmospheric concentrations of the greenhouse gases carbon dioxide, methane, chlorofluorocarbons (CFCs) and nitrous oxide. These increases will enhance the greenhouse effect, resulting on average in an additional warming of the Earth’s surface. The main greenhouse gas, water vapour, will increase in response to global warming and further enhance it

    Some of that, on the other hand, we are far from certain of. In particular, the claim that increasing GHGs will perforce warm the planet is a puerile and absurdly simplistic claim about a complex system. We have many examples of complex systems which do not respond in expected ways to changes in forcings. Assuming that the climate will respond linearly to climate is just that … an assumption. I do not know of a single observation that substantiates that claim of linearity, and the overwhelming lack of linearity in complex systems makes it an improbability, not a certainty in any sense.

    We calculate with confidence that:

    • some gases are potentially more effective than others at changing climate, and their relative effectiveness can be estimated. Carbon dioxide has been responsible for over half the enhanced greenhouse effect in the past, and is likely to remain so in the future

    “Calculate with confidence”??? What kind of bogus scientific statement is that? That’s handwaving. But I digress.

    Next, I would say that “some gases are theoretically more effective than others …”, but whether that is true in practice is a statement I have no confidence in.

    Also, the idea that CO2 has been responsible for “half the enhanced greenhouse effect in the past” has no observational substantiation. We do not know enough about the climate to say that with any confidence at all. Heck, we don’t even know if the “enhanced greenhouse effect” exists, because it assumes a net positive climate feedback for which we have no evidence. However, lack of evidence hasn’t ever stopped the IPCC from having “confidence” in their claims …

    • atmospheric concentrations of the long-lived gases (carbon dioxide, nitrous oxide and the CFCs) adjust only slowly to changes in emissions. Continued emissions of these gases at present rates would commit us to increased concentrations for centuries ahead. The longer emissions continue to increase at present day rates, the greater reductions would have to be for concentrations to stabilise at a given level.

    In my opinion, internally inconsistent. Atmospheric concentrations of the long-lived gases adjust immediately to increases in emissions, as any investigation of the year-over-year CO2 levels will verify. So to say the atmospheric concentrations “adjust slowly” to changes in emissions isn’t true. However, it is true that atmospheric concentrations decrease slowly if emissions decrease, and that if we continued to emit at current levels, the atmospheric concentration will not achieve equilibrium for a century or so.

    • the long-lived gases would require immediate reductions in emissions from human activities of over 60% to stabilise their concentrations at today’s levels, methane would require a 15-20% reduction

    I can’t replicate their math. If the carbon e-folding time is ~ 31 years, if we were to reduce our emissions by 60% tomorrow, the concentrations of the GHGs would start to drop right away, and would stabilize around 340 ppmv, far below today’s values. On the other hand, if we believe the e-folding time of the Bern Carbon Model of the IPCC, levels would continue to rise in the same scenario, and level off at about 420 ppmv. In neither case do they “stabilise their concentrations at today’s levels”. However, at the time of the First Assessment Report, they used different parameters in the Bern Model than are currently used, which likely gave the 60% reduction answer.

    What this means, of course, is that there are scientific questions about the accuracy of the Bern Carbon Model, questions which we do not have enough years of data to settle yet. So our confidence in this claim has to be low.

    Our judgement is that:

    • Global – mean surface air temperature has increased by 0.3°C to 0.6°C over the last 100 years, with the five global-average warmest years being in the 1980s. Over the same period global sea level has increased by 10-20cm. These increases have not been smooth with time, nor uniform over the globe

    Seems about right. However, I’m not sure why they have less confidence in this statement than in the ones above, since it is the only one of their claims that we have some actual data for. Perhaps their unfamiliarity with using real-world observations made them nervous and less certain of their claims.

    • The size of this warming is broadly consistent with predictions of climate models, but it is also of the same magnitude as natural climate variability. Thus the observed increase could be largely due to this natural variability, alternatively this variability and other human factors could have offset a still larger human-induced greenhouse warming. The unequivocal detection of the enhanced greenhouse effect from observations is not likely for a decade or more.

    True, although their estimate of a decade for observational detection is already off by 100%, and is likely off by something up to an order of magnitude.

    Also, when someone says that a fact is “broadly consistent with” the models, I get real nervous. The models are all over the board (and more so 20 years ago), so I find it hard to imagine any result that is not “broadly consistent with” the models.

    • There is no firm evidence that climate has become more variable over the last few decades However, with an increase in the mean temperature, episodes of high temperatures will most likely become more frequent in the future, and cold episodes less frequent

    This last one is brought to you by the Ministry of the Blindingly Obvious, and is of a piece with the claim that “X out of the last ten years are among the top ten warmest years” … I point out the idiocy of this claim here. True but meaningless.

    Overall? As you said, the First Assessment Report was much better than the SAR, the TAR, or the FAR … but that’s not saying much. Unfortunately, what we know with confidence about the climate system is dwarfed by what we don’t know about the climate system.

    • Willis, your argument basically boils down to “if it’s hard to understand, we minus well wave our arms in the air and call it a lost cause.” Sorry, but scientists have to move away from freshman-level stuff eventually and understand complex systems. Just because you don’t know the biological processes that act to regulate body temperature, doesn’t mean biologists don’t. Your arguments allows for denial of any conceivable evidence on the grounds we don’t understand everything. This is just not convincing.

      • Chris, it would be far more convincing if, instead of just saying “your argument basically boils down to …” and then dismissing this, you actually engaged with the points Willis made. I’m pretty sure he doesn’t agree with you about what his arguments (note the plural) “basically boil down to”.

        As a basic point of debate, I never find it very convincing when someone purports to summarize an opponent’s arguments into one sentence, then dismisses that sentence. It’s too close to a straw man.

      • Alex, fair enough.

        Stuff like ‘some greenhouse gases are more effective than others’ is radiative transfer of the most basic sort, and no imaginable amount of “complexity” , whether it be ENSO prediction, how gravity waves work, whether you can simulate the synoptic-scale cyclone forming over your part of the country, or whatever is going to change that. If you can’t understand the issues of band saturation, spectral selective absorption, etc then you just aren’t in a place to make authoritative judgments on the quality of climate science. Complexity is a reason for study, but it’s not an excuse to make things up or dismiss the many, many things we do know about climate.

        In fact, many features of the climate system can be understood purely by re-arranging some equations together or exercising a bit of physical intuition. One of most beautiful parts of my formal education in atmospheric science has been applying straightforward physics to complex systems and building off of those first-order results. In fact, even a rotating tank of water in the laboratory injected with colored dye to track the flow of water can give first-hand visual representations of the Hadley Circulation, the existence of an upper-level jet,an overturning ocean circulation, etc and other key features which make up the climate system. MIT’s opencourseware site provides an opportunity to see some of these rotating lab results (or to advertise, an AOS 800 level class here in Wisconsin-Madison, which should be supplemented by the core fluid dynamics courses and a class in Global Climate Processes, allow you to play with such experimental setups yourself).

        The global energy balance of the planet provides an immensely powerful boundary condition that constrains the global climate of all planets. To first order, differentiating between snowball Earth, Venus, modern Earth, and Mars, boils down to knowing something about the absorbed amount of sunlight and the optical properties of the atmosphere. As with any science, there’s of course fine structure and detail to interrogate after you build that basic understanding, but to argue that those details will cancel out everything we think we know requires an extraordinary amount of faith. For that matter, all the “complexity” could just as well amplify the CO2 forcing tenfold.

        Finally, countless papers and reports exist which cover much of the stuff described in the lead post and in the comments, a good citation is the NRC 2010 report on emission stabilization that I referenced above, which goes into good detail (and provides citation) for the long tail of CO2 removal in the atmosphere). It’s extremely difficult to engage in discussions if people aren’t going to read any of the literature out there, dismissing them with juvenile attacks like “…their unfamiliarity with using real-world observations made them nervous” and then yelling to “show me the evidence!!” on blogs. You might disagree with the science, but let’s have a little bit of academic self-respect.

      • Willis Eschenbach

        Chris Colose | November 15, 2010 at 1:55 am

        Stuff like ‘some greenhouse gases are more effective than others’ is radiative transfer of the most basic sort, and no imaginable amount of “complexity” , whether it be ENSO prediction, how gravity waves work, whether you can simulate the synoptic-scale cyclone forming over your part of the country, or whatever is going to change that. If you can’t understand the issues of band saturation, spectral selective absorption, etc then you just aren’t in a place to make authoritative judgments on the quality of climate science. Complexity is a reason for study, but it’s not an excuse to make things up or dismiss the many, many things we do know about climate.

        You are 100% correct … in theory. But how those gases work and interact with each other and the entire complex climate system in the real world is far, far from the “basic sort” of science you claim it is.

        It is this huge jump, from “CO2 is a greenhouse gas” to “therefore increasing CO2 will perforce make the world heat up”, that is the problem. It is identical to the jump from “the sun heats things up” to “therefore if I go out into the sun my core body temperature will rise”. The first statement is 100% true in a theoretical, “all other things being equal” sense. But it does not logically lead to the second statement in either case.

      • Willis, contamination-by-complexity is a hypothesis, and as stated is only an assertion. It’s also generally a very bad starting off point to science, which works by building up understanding, not by starting off with the assumption that everything is just “theory” and can’t be applied with confidence in practice. If this is the way you feel, it’s not just climate, it’s any physical science or system of “non-linear” behavior that can’t be understood with basic predictive equations (geology, astrophysics, behavioral ecology, evolutionary biology, etc) which you’re probably not going to be very comfortable with.

        The human body is an example of an extremely complex system and yet doctors have jobs because they can still get stuff right. If your hypothesis is right though it doesn’t seem like we’d be unable to do any valid radiative transfer modeling for our planet, Venus, etc or do satellite retrievals of data from space and get reasonable results–and yet we do. You say you don’t like models, but science at its core invokes ‘models’ to explain everything, with models ranging in all sorts of complexity.

        The “huge jump” you articulate is not an extravagant one, it merely requires knowledge of the planetary heat budget, and many key ‘signatures’ of the enhanced CO2 greenhouse effect (such as in spectra, or stratospheric cooling) have been detected. By the same logic of complexity, do you think it’s impossible to attribute cooling to the Pinatubo eruption to significant amounts of sulfate ejecta?

      • Willis,

        “It is this huge jump, from “CO2 is a greenhouse gas” to “therefore increasing CO2 will perforce make the world heat up”, that is the problem. It is identical to the jump from “the sun heats things up” to “therefore if I go out into the sun my core body temperature will rise”. The first statement is 100% true in a theoretical, “all other things being equal” sense. But it does not logically lead to the second statement in either case.

        As you know and have relied upon in past arguments, increasing C02 will ( all other things being equal) result in warming. Now, of course we have less certainty about the cases where all other things are not equal. What we know is that current climate theory would estimate that the increase in C02
        from 1850 to today ( under scenarios where other things are not equal) would result in an increase in temperature. That theory is bolstered by the observations. If temperature had gone down, you would surely point that out. here is what we dont have: we dont have a theory that:
        1. accepts the truth of RTEs (C02 warms, all other things being equal)
        2. estimates the effects when other things are not equal.
        3. predicts that more C02 will cool when all other effects are taken into account

        Here is what we do have: a theory that:
        1. accepts the truth of RTEs (C02 warms, all other things being equal)
        2. estimates the effects when other things are not equal.
        3. Agrees with the observation record.. gets the basics right (the sign) Warmer or cooler

        While it is leap from the calculations of RTEs to the “final” effect of more C02, it is not a leap of faith. further it is not a logical truth ( but no science is) It is a leap of modelling. Those models, while imprecise, do not predict a net cooling effect. If they did, they would not square with the observational record since 1850. they predict a net warming ,an amplified warming, a warming that is relatively close to the observed warming, a predicted warming that your own approach to understanding the climate could never make.
        yes, there is a lacuna between the undeniable physics of RTE and the projections of GCMs. Merely taking epistemological notice of that gap is not very edifying. Pointing out the shortcomings of scientists efforts to fill that gap is mundane. Coming up with a better model ( better than the shuolder shrug of “natural variability) is honest labor. Until somebody does the best science is the science we have. Absent some other quantifiable model to fill the gap, I’ll take a GCM. Its the best tool we have.

        You know when designing the flight control system for an aircraft, we might know the effect of various forcings in isolation. In the end we would have to build a model of the final effects. Sometimes the systems had narrow bounds, sometimes wide boundaries. But the complexity did not stop us from making physic based estimates. In no case did we ever let our fuzzy understand of all the physics stop us from building a working system.

      • Willis Eschenbach

        Steven Mosher, you say:

        As you know and have relied upon in past arguments, increasing C02 will ( all other things being equal) result in warming. Now, of course we have less certainty about the cases where all other things are not equal. What we know is that current climate theory would estimate that the increase in C02 from 1850 to today ( under scenarios where other things are not equal) would result in an increase in temperature. That theory is bolstered by the observations. If temperature had gone down, you would surely point that out. here is what we dont have: we dont have a theory that:

        1. accepts the truth of RTEs (C02 warms, all other things being equal)
        2. estimates the effects when other things are not equal.
        3. predicts that more C02 will cool when all other effects are taken into account

        Here is what we do have: a theory that:
        1. accepts the truth of RTEs (C02 warms, all other things being equal)
        2. estimates the effects when other things are not equal.
        3. Agrees with the observation record.. gets the basics right (the sign) Warmer or cooler

        Here is what we don’t have: a theory that explains why the earth warmed from say 1700 to 1800, or why it cooled from say 1500 to 1650.

        Since we don’t have that, we have no way to distinguish putative CO2 warming from natural warming. And since the world has generally been warming since the Little Ice Age, any theory of why it is warming now that doesn’t explain why it was warming then is greatly weakened. Our long-term records show no statistical difference between times of non-GHG warming and times of putative GHG warming.

        You see, you’ve left out a possibility—a theory that accepts RTEs etc., estimates the effects etc., and concludes that CO2 doesn’t make a whole lot of difference. My Thunderstorm Thermostat Hypothesis is one such theory, there are others. And since recent rises in CO2 have not produced statistically unusual warming, such a theory has to be counted as a possibility.

        Yes, model results give you CO2 warming as you say … but each model is using different forcings, yet they get the same result that increasing CO2 increases temperatures. Perhaps this is connected to the fact that the people who built the models believe implicitly that CO2 causes increasing temperatures … I have learned to my cost that such preconceptions in model building are lethal.

        So yes, we do have a CO2 theory that explains the 1900-2000 temperature rise (although the theory hasn’t performed well since then). But we don’t have the slightest indication that the 1900-2000 temperature rise is a historical anomaly.

        Finally, I fear that people have missed my point when I described the climate system as being a non-linear complex system. Likely my fault for lack of clarity. What I mean is that the climate, like a river, like the human body, contains homeostatic mechanisms that can entirely over-ride forcings. Consider a river. Sure, you can cut through an oxbow bend and shorten the river. But the river will then lengthen to compensate. That is what I mean by non-linearity of complex systems. My forcing (cutting through the river) did not result in a long-term change in the length of the river. It’s not “non-linear” in the sense that there is a kink in a graph. It is non-linear in the sense that forcings may not be connected to the length of the river at all.

        Flow systems which are far from equilibrium do not just randomly assume one or another of the myriad of possible flow states. Instead, the system itself constantly readjusts to maintain preferred states. (Generally these are related to maximizing the total of energy produced plus energy that goes to heat, see the Constructal Law for lots of examples). That is the issue that I am trying to point out. Flow systems have preferred states, and changes in forcings may or may not change those preferred states very much.

        So no, we do not have a theory that agrees with the observational record. The “CO2 drives climate” theory does not agree with what we know of the temperatures since the Little Ice Age. CO2 was nearly stable for most of that time, but temperatures still went up for most of that time. How does that agree with the CO2 theory? If CO2 is the climate control knob, the global thermostat, as is claimed, then why wasn’t the temperature stable then?

      • Willis:
        “Here is what we don’t have: a theory that explains why the earth warmed from say 1700 to 1800, or why it cooled from say 1500 to 1650.

        1. Unfortunately as you well know you dont have observations from 1700 to 1800 that are worth anything.
        2. you dont have observations from 1500 to 1650 that are worth anything.
        You can hardly hold this against AGW. Simply, for the BEST observations we have (1850 to present) The best theory we have , is counter to what you claim.

        “Since we don’t have that, we have no way to distinguish putative CO2 warming from natural warming. And since the world has generally been warming since the Little Ice Age, any theory of why it is warming now that doesn’t explain why it was warming then is greatly weakened. Our long-term records show no statistical difference between times of non-GHG warming and times of putative GHG warming.”

        No Theory can categoricially rule out gremlins. Until you quantify “natural variation” you’re complaint is that the best theory is wrong because it doesnt rule out gremlins.

        “You see, you’ve left out a possibility—a theory that accepts RTEs etc., estimates the effects etc., and concludes that CO2 doesn’t make a whole lot of difference. My Thunderstorm Thermostat Hypothesis is one such theory, there are others. And since recent rises in CO2 have not produced statistically unusual warming, such a theory has to be counted as a possibility.”

        Your theory is qualitative hocum. But lets test it. Provide the math and lets do some paleo runs? heck lets see what your theory would PREDICT for the temps from 1850 to today. it would predict nothing. its not a theory.

        “Yes, model results give you CO2 warming as you say … but each model is using different forcings, yet they get the same result that increasing CO2 increases temperatures. Perhaps this is connected to the fact that the people who built the models believe implicitly that CO2 causes increasing temperatures … I have learned to my cost that such preconceptions in model building are lethal.”

        I’ll take it that you never spent a single minute looking at the source code. The assumptions you state are not there.
        AND you miss the point to boot.

        “So yes, we do have a CO2 theory that explains the 1900-2000 temperature rise (although the theory hasn’t performed well since then). But we don’t have the slightest indication that the 1900-2000 temperature rise is a historical anomaly.”

        Since when does something have to be a historic anomaly.
        Look willis, the cooling from volcanoes is not “unprecendented” but your toy theory cant explain it. A GCM can and does. Your theory would predict nothing from 1900 to today and you think it superior merely because it doesnt fail at game it cant play.

        “Finally, I fear that people have missed my point when I described the climate system as being a non-linear complex system. Likely my fault for lack of clarity. What I mean is that the climate, like a river, like the human body, contains homeostatic mechanisms that can entirely over-ride forcings. Consider a river. Sure, you can cut through an oxbow bend and shorten the river. But the river will then lengthen to compensate. That is what I mean by non-linearity of complex systems. My forcing (cutting through the river) did not result in a long-term change in the length of the river. It’s not “non-linear” in the sense that there is a kink in a graph. It is non-linear in the sense that forcings may not be connected to the length of the river at all.

        Flow systems which are far from equilibrium do not just randomly assume one or another of the myriad of possible flow states. Instead, the system itself constantly readjusts to maintain preferred states. (Generally these are related to maximizing the total of energy produced plus energy that goes to heat, see the Constructal Law for lots of examples). That is the issue that I am trying to point out. Flow systems have preferred states, and changes in forcings may or may not change those preferred states very much.”

        Hocum. Blather. Sorry, willis, show me your code for this.

        “So no, we do not have a theory that agrees with the observational record.”

        yes we do.

        “The “CO2 drives climate” theory does not agree with what we know of the temperatures since the Little Ice Age. CO2 was nearly stable for most of that time, but temperatures still went up for most of that time. How does that agree with the CO2 theory? If CO2 is the climate control knob, the global thermostat, as is claimed, then why wasn’t the temperature stable then?”

        Good grief. It’s the most important knob, not the only knob. I turned the AC on yesterday and it first got warmer in my house. WTF.. oh ya, lag. duh.

      • Willis Eschenbach

        Steven Mosher | November 17, 2010 at 8:54 am

        Willis:

        “Here is what we don’t have: a theory that explains why the earth warmed from say 1700 to 1800, or why it cooled from say 1500 to 1650.

        1. Unfortunately as you well know you dont have observations from 1700 to 1800 that are worth anything.
        2. you dont have observations from 1500 to 1650 that are worth anything.
        You can hardly hold this against AGW. Simply, for the BEST observations we have (1850 to present) The best theory we have , is counter to what you claim.

        I love the “CO2 must be the driver, it’s the best theory we have” claim. Since it does no better than a straight line at explaining temperature, that is a pathetically weak argument.

        I do like the idea that we can just ignore everything prior to 1850. It makes the problem so much more tractable …

        “Since we don’t have that, we have no way to distinguish putative CO2 warming from natural warming. And since the world has generally been warming since the Little Ice Age, any theory of why it is warming now that doesn’t explain why it was warming then is greatly weakened. Our long-term records show no statistical difference between times of non-GHG warming and times of putative GHG warming.”

        No Theory can categoricially rule out gremlins. Until you quantify “natural variation” you’re complaint is that the best theory is wrong because it doesnt rule out gremlins.

        Gremlins. The lack of any statistical anomaly or unusualness of the temperature records is due to gremlins … hey, you got me there, Mosh …

        “You see, you’ve left out a possibility—a theory that accepts RTEs etc., estimates the effects etc., and concludes that CO2 doesn’t make a whole lot of difference. My Thunderstorm Thermostat Hypothesis is one such theory, there are others. And since recent rises in CO2 have not produced statistically unusual warming, such a theory has to be counted as a possibility.”

        Your theory is qualitative hocum. But lets test it. Provide the math and lets do some paleo runs? heck lets see what your theory would PREDICT for the temps from 1850 to today. it would predict nothing. its not a theory.

        Ummmm … you do understand why my yypothesis is called a hypothesis, yes? Because it is qualitative? And we were discussing theories, not fully fledged branches of science. You discussed the theories that we have. I say there are more things in heaven and earth, Horatio, than are dreamed of in your philosphy … and you demand photographs.

        “Yes, model results give you CO2 warming as you say … but each model is using different forcings, yet they get the same result that increasing CO2 increases temperatures. Perhaps this is connected to the fact that the people who built the models believe implicitly that CO2 causes increasing temperatures … I have learned to my cost that such preconceptions in model building are lethal.”

        I’ll take it that you never spent a single minute looking at the source code. The assumptions you state are not there.
        AND you miss the point to boot.

        I have spent hours and hours and hours looking at the source code. I’ll take your foolish claim as typical of your discussion style. And if you would actually list the “assumptions” that I state that are not there, we might have something to discuss, instead of you just flinging empty allegations around.

        “So yes, we do have a CO2 theory that explains the 1900-2000 temperature rise (although the theory hasn’t performed well since then). But we don’t have the slightest indication that the 1900-2000 temperature rise is a historical anomaly.”

        Since when does something have to be a historic anomaly.
        Look willis, the cooling from volcanoes is not “unprecendented” but your toy theory cant explain it. A GCM can and does. Your theory would predict nothing from 1900 to today and you think it superior merely because it doesnt fail at game it cant play.

        OK, I’ll see if I can make this clearer. Science is used to explain the unusual. If the weather is the same every day, we don’t look for scientific reasons for a usual day. But if the temperature suddenly starts to rise, that is an anomaly that needs explanation. It’s kinda the precursor to the scientific method. Because if our temperatures are no different from what we have seen from the last couple centuries (a gradual rise), then just what is it that you are trying to explain?

        Can my theory explain volcanoes? My theory can explain the shape of the response to volcanoes (overshoot), which the GCMs don’t and can’t.

        “Finally, I fear that people have missed my point when I described the climate system as being a non-linear complex system. Likely my fault for lack of clarity. What I mean is that the climate, like a river, like the human body, contains homeostatic mechanisms that can entirely over-ride forcings. Consider a river. Sure, you can cut through an oxbow bend and shorten the river. But the river will then lengthen to compensate. That is what I mean by non-linearity of complex systems. My forcing (cutting through the river) did not result in a long-term change in the length of the river. It’s not “non-linear” in the sense that there is a kink in a graph. It is non-linear in the sense that forcings may not be connected to the length of the river at all.

        Flow systems which are far from equilibrium do not just randomly assume one or another of the myriad of possible flow states. Instead, the system itself constantly readjusts to maintain preferred states. (Generally these are related to maximizing the total of energy produced plus energy that goes to heat, see the Constructal Law for lots of examples). That is the issue that I am trying to point out. Flow systems have preferred states, and changes in forcings may or may not change those preferred states very much.”

        Hocum. Blather. Sorry, willis, show me your code for this.

        You’re like the guy trying to explain the temperature in the house. Someone finally says “the house stays the same temperature because it has a thermostat”. His response is “Hocum. Blather. Show me the your code.” You don’t seem to get the fact that we are talking about a theoretical framework. The Constructal Law shows that all flow systems rearrange themselves to maximize some variable. If you think that it doesn’t apply to the climate, that’s fine … but it remains a very strong possibility.

        “The “CO2 drives climate” theory does not agree with what we know of the temperatures since the Little Ice Age. CO2 was nearly stable for most of that time, but temperatures still went up for most of that time. How does that agree with the CO2 theory? If CO2 is the climate control knob, the global thermostat, as is claimed, then why wasn’t the temperature stable then?”

        Good grief. It’s the most important knob, not the only knob. I turned the AC on yesterday and it first got warmer in my house. WTF.. oh ya, lag. duh.

        OK, glad to know that, the “lag” explains why climate warmed from 1650 to the present … to borrow a page from your book, since you believe in this “lag”, surely you can show me the code for the “lag”, and demonstrate mathematically just how that “lag” makes the earth warm for 300 years?

      • Willis Eschenbach

        Chris, your most telling comment is

        For that matter, all the “complexity” could just as well amplify the CO2 forcing tenfold.

        You are quite correct, it could do that … which is why your certainty in the real-world actual effect of a change in CO2 is terribly misplaced. You seem to simultaneously believe that we know exactly what CO2 will do if it increases, and at the same time believe that your results could be out by an order of magnitude.

        You certain about that?

      • I don’t believe in the very high sensitivity, it’s just an example of the “complexity” argument working both ways. I believe there’s constraints though, albeit fairly large ones (2 to 4.5 C/2xCO2 at equilibrium). That doesn’t allow me to make up stuff.

      • You ‘believe’…or you can demonstrate confidently, repeatedly and with observations of the real world – to the satisfaction of both your peers and critics?

        The two, as you know, are very different things.

        Or to put it another way…

        Have you done any experiments to prove it..or is it all jsut theory?

        I do not need to be an absolute expert in all the radiative physics to judge that all theory and all models with no experimental proof does not necessarily lead to the ‘correct’ answer. Been there, done that – did not get the Tshirt.

      • Climatologists are unable to demonstrate the validity of their claims in repeated trials because they are extraordinarily short on observed statistical events. If the averaging period that defines the climate is 20 years and the temperature and CO2 records are unreliable before 1850 then the claims of climatology must be based upon 8 independent observed statistical events. That’s way too few.

      • Effective degrees of freedom
        Moving Average

        For 150 years of data and a 20 year moving average I get 150 – 7.5 = 142.5 degrees of freedom (7.5 is the trace of a moving average matrix, I assumed a trailing average, and the first twenty years are all just the average of the first twenty years) to use in making inferences. For example, the first couple rows of a two year moving average matrix would look like:
        [1/2 1/2 0 … 0]
        [1/2 1/2 0 … 0]
        [0 1/2 1/2 0 … 0]
        ….

        If, instead, you use the first twenty years directly with no smoothing, for the two year smooth it would look like:
        [1 0 … 0]
        [1/2 1/2 0 … 0]

        You get a trace of 26.5, which gives 150 – 26.5 = 123.5 degrees of freedom for making inferences.

        What math do you use to get “8 independent observed statistical events”? How does this relate to making inferences about your smooth (model) of the data?

      • OK, that’s more substantive. Even so, you have apparently missed (for example) that there is at least one point Willis made that I’m sure you agree with (ie there is a greenhouse effect, point one of the FAR extract). Further, from my reading Willis wasn’t disagreeing about it being a long time before CO2 levels stabilized, only doubting the exact calculation proposed (in fact, one of the alternative approaches he mentioned would lead to stabilization at a higher level than the FAR suggested).

        So in summary, I think the need for respect cuts both ways.

      • @chris colose

        ‘If you can’t understand the issues of band saturation, spectral selective absorption, etc then you just aren’t in a place to make authoritative judgments on the quality of climate science’.

        I wonder how many of the ‘97% of the climate scientists’ who supposedly form the ‘consensus’, are real experts with a deep understanding of these particular topics. Gavin Schmidt? Mikey Mann? Phil Jones? Perhaps the ‘etc’ is their specialist subject.

        They seem to believe, however, that their judgment is authoritative, despite this lack of knowledge. Please let me know how (given your assertion above) they manage to do so with their scientific integrity intact.

      • And what about the “parrot” scientists in other fields who predict dire results in just about any natural science field you can imagine due to global warming. I seriously doubt these guys, for the most part, have a clue about radioactive physics, much less the more complex aspects of climate science. Unfortunately, that doesn’t stop them from predicting species loss and other catastrophes.

      • Make that “radiative” physics. I really need to check these more closely!

      • Here is a great example of “radiative” physics.

        Look at all those nice brown nitrogenous oxides! Yummy.

      • Well, I’m learning something at least. From what I’m reading, it appears that thunderstorms occur more often over land because land diverts the winds in an upward direction, starting the convection process. Maybe all we have to do in order to cool the planet is create some wind diverters at sea. (I take it you were making a joke about the brown coloration of the map. Of course, there would also be enhanced NOX. )

      • When you mentioned “radiative” physics, I was reminded of all that was unknown and learned in the era of atmospheric nuclear weapons testing. Nonlinear radiative, dissipative and disbursal effects of various forms appears to have been a big unknown. (At least, so sayeth some of the declassified documents that have been released since then. That wouldn’t be a bad place to re-visit in considering atmospheric physics. Newer generations of scientist might be unaware of the relevance of those earlier experiments.)

        From what I’m reading, it appears that thunderstorms occur more often over land because land diverts the winds in an upward direction, starting the convection process.

        If that’s the case then windmills might retard this activity.

        … As for inversion layers?

      • I couldn’t view your AB until later today. Very funny! I was thinking of the NOX created by lightning in the thunderstorms. I still wonder if the climate models predict more energetic TS over land and the tropics. Does anyone know?

      • Sorry Chris, but this is simply condescending and arrogant: “If you can’t understand the issues of band saturation, spectral selective absorption, etc then you just aren’t in a place to make authoritative judgments on the quality of climate science.”

        With a background in optics, this is pretty basic to me but I suspect very few IPCC AR4 authors have any depth of understanding in this area. We all have areas of expertise. Strength or weakness in one aspect of climate science does not render ones opinion irrelevant.

        How strong are your skills and understanding of 1H2H16O and 1H218O to determine paleo climate from ice core analysis? A key component in our record of past climate change. I am sure there are some online “800 level” courses available for you to brush up.

      • I’ll accept a poor phrasing of my argument.

      • Perhaps you’d like to think of a more felicitous one?

        Because it smacks of that sense of arrogant entitlement that seems to be a feature of many climatologists. It may be that you learn this early in your climatology career from your ‘elders’ so is not entirely your fault.

        But it is doing you no favours bigtime in public debate.

      • Chris Colose: To first order, differentiating between snowball Earth, Venus, modern Earth, and Mars, boils down to knowing something about the absorbed amount of sunlight and the optical properties of the atmosphere.

        And I ignorantly assumed that it had to do with the elemental ratio compositions of those assorted planetary bodies. Go figure.

      • Complexity is a reason for study, but it’s not an excuse to make things up or dismiss the many, many things we do know about climate.

        In fact, many features of the climate system can be understood purely by re-arranging some equations together or exercising a bit of physical intuition. One of most beautiful parts of my formal education in atmospheric science has been applying straightforward physics to complex systems and building off of those first-order results.

        Agree.

        The global energy balance of the planet provides an immensely powerful boundary condition that constrains the global climate of all planets. To first order, differentiating between snowball Earth, Venus, modern Earth, and Mars, boils down to knowing something about the absorbed amount of sunlight and the optical properties of the atmosphere.

        Agree strongly but also disagree.

        The evolution, arrangement and development and on the many many included phase states (those active,participating boundary conditions) is complicated,unknown and alters the pattern of heat flux and re-radiation.

        Past events on earth do not represent a full example of all possible configurations. Predicting how the biota has responded in the past and might be primed to do so in the future is an open issue.

        The physics is easy.

        The endless multiplicity of possible boundary configurations is hard to imagine.

        On top of it all is the tendency of complex system to create and aggregate phase states which engage and alter the fluxes of heat and radiation. That is a general consequence of interactions carried over extended durations.

        As each decade progresses, science discovers nature is all the richer in complex phase interactions.

        The simple laws of fluid dynamics and radiation are pertain. They pertain within the milieu of unanticipated and poorly understood structures.

        You are welcome to your optimism.

        I shall leave (again) because I know that I can make better progress elsewhere, A danmable place of solitude which has become gutted as a result of physicists excessive premature confidence and blind arrogance.

        Might I suggest you look into the topic of “Environmental Peace” being offered by one of your environmental colleagues and supporters. I certainly won’t waste another moment’s thought on that subject either.l

    • Willis:

      ” We calculate with confidence that:

      • some gases are potentially more effective than others at changing climate, and their relative effectiveness can be estimated. Carbon dioxide has been responsible for over half the enhanced greenhouse effect in the past, and is likely to remain so in the future

      “Calculate with confidence”??? What kind of bogus scientific statement is that? That’s handwaving. But I digress.”

      ######
      Willis, you can certainly agree that RTE’s ( since you used them in the past) are clearly not armwaving. If you take a Modtran result as a first order estimate you can see that we do have good calculations about this.

      • Willis was quite specific about his point. He said

        “Next, I would say that “some gases are theoretically more effective than others …”, but whether that is true in practice is a statement I have no confidence in.”

        This appears to be exactly what you are saying however he is coming at it from the skeptical angle whereas you and Chris appear to be coming at it from the “its a given” angle.

    • “I would agree this is certain” – I’d prefer “uncontroversial”.

      “Perhaps their unfamiliarity with using real-world observations made them nervous and less certain of their claims.” is vintage Esch – thanks.

    • Well..

      – First, there is no assumption of linearity. If we made this assumption, then we would be assuming that a doubling of CO2 would leading to a doubling of the natural greenhouse effect, i.e. a rise in temperatures of 33K!

      – Second, we can calculate the natural enhanced greenhouse effect and check it against observation. If the natural effect did not exist we’d all be frozen solid, and I can assure youy that we are not. If you dispute this then you are going to have to show your working.

      – You claims about CO2 lifetimes don’t seem to actually go anywhere.

      – And you point to a post on WUWT which would make a textbook example of cherry picking, not to mention bad statistics.

      • “If we made this assumption, then we would be assuming that a doubling of CO2 would leading to a doubling of the natural greenhouse effect, i.e. a rise in temperatures of 33K!”

        No, starting at 1 we have already had 8 doublings. 1,2,4,8,16,32,64,128 to 256 ppm. The jump from 1 ppm to 2 ppm has the same effect as the jump from 256 to 512 ppm all other things being equal unless I’ve gotten my radiative physics wrong. Humanity had nothing to do with the 1st 8 doublings. Since we are all here then the 1st 8 doublings doesn’t appear to have been harmful.

      • harrywr2

        Nicely put!

        Though a bit oversimplified, as CO2’s GHG effect is logarithmic, warming from 1 ppm to 2 ppm would be greater than 2 ppm to 4 ppm, etc., if I understand the predictions.

        Also, these are hypothetical doublings, since doublings 10-14 happened in the geological past, so we got to where we are by halvings.

        Humanity is the result of the conditions of the first 14 doublings and next 6 halvings, which settled millions of years before we evolved.

        Since we are all here, we have the opportunity to go the way of what life dominated at the end of the first 10 net doublings minus halvings.

        Which, they mostly ain’t here no mo’ fo’ long long time past.

      • It is somewhat picky, but at 1-2 ppm or 2-4, the effects would be linear. it is only when you get up to ~50 ppm or so that the logarithmic nature of the effect begins to kick in. You can play around with http://www.spectralcalc.com/calc/spectralcalc.php to verify this yourself. Indeed, it is the fact that the mixing ratio of methane is so much smaller that makes it more effective as a greenhouse gas

      • Eli

        Greatly appreciated

        I learn something where before I was wrong _and_ get a new online toy to play with!

        Double dividend.

        Thanks

        PS nothing wrong with being picky, I’m sure there’s other things about my argument that could be said better, too.

      • Hmmm.

        What’s so magical about 1ppm?

        Wait – we’ve has doublings from 0.5ppm! 0.25ppm! 0.125ppm!

        Come to think of it, half of the entire greenhouse effect must have been provided by the first molecule of CO2, if I follow your logic.

        You have got your physics wrong.. the atmosphere cannot be approximated by a single sheet, even a basic working model has to include height and density, which you are not; in this case extra CO2 or other greenhouse gasses will always increase the surface temperature, by increasing the saturation altitude, which will adiabatically warm the surface.

        I’d also point out that although the earth will indeed survive CO2 levels of 1000ppm, those species that depend on coastlines staying where they are, rivers keeping their flow and crops growing may find things a bit trickier.

    • Some of that, on the other hand, we are far from certain of. In particular, the claim that increasing GHGs will perforce warm the planet is a puerile and absurdly simplistic claim about a complex system. We have many examples of complex systems which do not respond in expected ways to changes in forcings. Assuming that the climate will respond linearly to climate is just that … an assumption. I do not know of a single observation that substantiates that claim of linearity, and the overwhelming lack of linearity in complex systems makes it an improbability, not a certainty in any sense.

      The earth is complex internally, but the energy arriving and leaving is not so complex. We know more energy is being absorbed into the climate system. Unless you know of some way that energy is going to magically disappear, then it will get warmer. The only question is by how much.

      • Snide says: “The earth is complex internally, but the energy arriving and leaving is not so complex. We know more energy is being absorbed into the climate system. Unless you know of some way that energy is going to magically disappear, then it will get warmer. The only question is by how much.”

        So how do you explain the Ice Ages? It seems to me that if what you say is true, then the Earth should have continually warmed over its entire history.

      • I’m guessing he means the system is absorbing more energy from the greenhouse effect.

        My technical explanation for the Ice Ages: it got cold.

      • The ice ages were the result of less energy arriving or being retained.

      • The common metaphor is a bath with water running in at the top, and out the bottom down the plughole. The water is coming in at the same rate it is leaving, the water level will stay the same. The nozzle at the top controls the rate at which water, that is, the energy, is arriving at the earth, the plughole controls the rate at which it leaves.

        What if the rate of water coming in varies by turning the tap? What if the size of the hole varies, changing the rate at which it drains? By closing the plughole a bit, we are not making more energy enter, but we are slowing the rate at which it leaves. The water level rises, but we have not touched the tap.

        For arguments sake, (not sure if this is true, but can’t be bothered working out the physics for the sake of the analogy), as the water level rises, it pushes harder on the water leaving, slightly increasing the outflow. The water level will rise, till there is a new equilibrium reached.

      • An intriguing question in hydrodynamics. I’m sure the properties of the aperture and many other variables could come into play.

        I think, in short, you’d end up with endless quibblers playing in bathtubs.

        Which, not a bad metaphor, overall.

      • For those with an EE background, I drew a connection with Ohm’s Law to illustrate the greenhouse effect with a current source (sun), a capacitor (earth) and a resistive discharge path (the atmosphere) here . Ice ages are due to a low value for the current source. The leaky bucket analogy is equally good.

      • Hmm. I’m afraid that people are trying to simplify this a bit too much. The earth is sufficiently complex that the same amount of energy coming in can have different effects, depending on the timing and location of the incoming energy. That is one of the underlying reasons why the degree of eccentricity of the earth’s orbit and the earth’ s axial tilt can affect the climate.

      • That is correct, but the Milankovich cycles aren’t active at this point in time.

      • That’s an odd statement. The Milankovitch cycles are surely always active. Isn’t that why we are currently in an interglacial period?

  7. What do I think is a better way of describing our understanding relative to confidence and likelihood?

    I think analogy may be a better approach than broad abstract categories.

    In a previous post (https://judithcurry.com/2010/11/10/uncertainty-gets-a-seat-at-the-%e2%80%9cbig-table%e2%80%9d/#comment-10837), I likened probability and uncertainty to Las Vegas and Drive-Ins.

    Las Vegas is built on probabilities (risk, chance, odds) with the goal of reducing the uncertainties; Drive-Ins are never a risk or matter of chance, but remain constantly under the threat of uncertainties beyond their control.

    What light can the comparative histories of these two American institutions, both familiar to and beloved by so many policy makers, shed on the topics of confidence and likelihood?

    In Las Vegas, likelihoods are low (just slightly favoring the Dealer), and confidence is high and controlled.

    In Drive-Ins, likelihoods are extremely high, while confidence (in weather in the short range, finding a good spot near the concession and with a good view, real-estate prices pushing the property owner to sell, passion-pit morality issues, and so on) is very low.

    Las Vegas is a stable staple of American life today.

    Drive-Ins are little more than nostalgia.

    Compare how Las Vegas responded to threats to confidence (crime, morality issues, cheating, dishonest dealers) by organizing both government and voluntary policing and proactively using the best technology, expertise and promotion available at every point, with how Drive-Ins floundered, trying to control weather effects and short showing times (after dark) by failed giant tent experiments, trying to lobby against televisions as a threat to their industry, moving further and further from cities as land prices soared, and so on.

    It doesn’t take much to mine these two examples for countless relevant comparisons accessible to the understanding of policy makers and the general public.

    Few people really can’t grasp the issues, once stated in familiar context, I believe.

    Once they comprehend, they may still not agree, but at least they’ll be disagreeing from the same common base of understanding, which is infinitely preferable to the chaos we have now.

  8. The size of this warming is broadly consistent with predictions of climate models, but it is also of the same magnitude as natural climate variability Thus the observed increase could be largely due to this natural variability, alternatively this variability and other human factors could have offset a still larger human-induced greenhouse warming The unequivocal detection of the enhanced greenhouse effect from observations is not likely for a decade or more.

    Bringing this into the present and looking back I thought today’s climate models significantly over estimate the rate of change in temperature (“Panel and Multivariate Methods for Tests of Trend Equivalence in Climate Data Series” 2010 McKitrick et al). However this is more a commentary on climate models than evidence or otherwise for AGW (something there seems to be a curious lack of understanding of in this subject area).

    Others have commented on the use of “broadly consistent with”: – that again tells us little about the evidence or otherwise for AGW.

    In the spirit of trying to find the common ground I’d suggest a proposition something like:

    “Climate models have not been adequately validated against the actual behaviour of the climate and the level of uncertainty around their forecast has been generally understated. Thus their use for long-term forecasts of climate change under various assumptions remains controversial. Other techniques such as stochastic models may provide better information for policy purposes.”

    Or perhaps that wasn’t helpful in trying to get a consensus.

    • Bruce Cunningham

      “Climate models have not been adequately validated against the actual behaviour of the climate and the level of uncertainty around their forecast has been generally understated. Thus their use for long-term forecasts of climate change under various assumptions remains controversial. Other techniques such as stochastic models may provide better information for policy purposes.”

      Spot on!

  9. I’ve sat down and drawn the CO2 curve myself, and the necessity of doubling of concentration to achieve the same temperature increase flattens the curve quickly. Without feedback I can’t see increasing CO2 levels as any kind of a problem. But has anyone determined definitively that the feedback is positive, or do most simply assume that it is? My understanding is that all IPCC models assume positive feedback, am I wrong about that (just asking)? None of the effects cited for temp increase (.6′ C) and sea level increase (30 cm) are remotely troubling, and yet did they not by definition occur on a steeper part of the CO2 curve? Based on the shape of the curve, why would people assume worse effects in the future from a flatter CO2 level of contribution unless they understood the feedback mechanisms precisely? If there is a high degree of correlation between temperature and CO2 concentration, and CO2 concentrations have continued to increase while temperatures have not, then doesn’t the feedback have to be negative (or at least a large proportion of it)?

    • Hi Chip,

      You ask good questions. It’s very nice to see people express unfamiliarity with the science in the form of question marks rather than exclamation points, and I’ll be happy to discuss these issues.

      You are correct that the logarithmic effect of CO2 means that every doubling of concentration produces the same forcing. This is fundamentally a consequence of the way absorption saturates away from the line center . Whether or not the no-feedback amount of warming this produces is a problem is more of a value and a local political/economic issue than a scientific one, so I’ll leave that unanswered. Though, it’s not really right to say that some of the impacts don’t occur “by definition” in a low sensitivity world.

      You ask about feedbacks. Feedbacks in models are emergent properties, they aren’t “assumed to be positive.” Some of them are very intuitive (less ice over a better absorbing surface means solar absorption is enhanced) but some are not, such as cloud responses, and in fact various models produce feedbacks of different magnitude or even sign in that regard (most predominately on the shortwave side of the feedback effect). This is widely recognized to be a big question in climate projection, and not just for modern AGW issues– how clouds are relevant for setting the threshold for Venus to get in a runaway greenhouse state, or how they might effect habitability on exoplanets, is just as much a big question in astrophysical issues.

      The key support for climate sensitivity estimates is Earth’s history, although we have a strong basis of observational support for individual feedbacks such as the water vapor feedback. This doesn’t allow us to know the feedback magnitude issues “precisely” but it provides constraints, some of those are that a very low sensitivity (like half a degree per doubling) or a very high sensitivity (like 10 degrees per doubling) are extremely unlikely to be real based on the convergence of various lines of evidence (see Knutti and Hegerl, 2008 for a review that is still pretty up-to-date). My aim here is not to argue this, only to describe the current thought on the subject and where several lines of information have pointed climate and geoscientists to. I talk about these in my recent RealClimate articles on feedbacks.

      Finally, more pertinent to climate change than “CO2” is the total forcing (CO2 +aerosols +methane+natural factors like sunlight, etc).

      • ” Some of them are very intuitive (less ice over a better absorbing surface means solar absorption is enhanced) ”

        You have different intuition to me then because open water is also intuitively better at radiating heat than ice and I expect changes the convection of the water too. It seems to me that if warmer waters were flowing from the south then the Earth may lose more energy as a net result.

        ps…sorry about the duplicate post down lower. I dont know what happened there…

      • Ice reflects (solar) shortwave radiation back into space.

      • …and ice acts like a blanket to the ocean. Which effect wins as a feedback?

        This is the problem with looking at effects in isolation. You cant. You just cant.

      • If the ocean and surface is warming, the ice melt will produce a positive feedback, if it cools, the feedbacks work the other way. From what I remember, the sensitivity at 2xCo2 is between .2 and .4 Wm 2. This is inserted into simple radiative forcing equations as one of the feedback mechanisms, along with water vapor, clouds, etc.

      • “If the ocean and surface is warming, the ice melt will produce a positive feedback, if it cools, the feedbacks work the other way.”

        Consider this, if the oceans warmed to the point where ice never quite formed all year around (and migrating warmer southern waters kept it this way) then this would be at the limit of the effect of ice reduction.

        In this case the oceans gain energy for 4-5 months of the year due to additional SW radiation but lose LW energy all year and particularly for the 7-8 months of darkness and intuitively this is a negative feedback.

        So where did you “intuition” get positive feedback for decreased ice from?

      • TTTM,
        The situation you describe is like El Nino where warmer water expands in area. The extra energy goes to the atmosphere, leading to average atmospheric warming in those years. So, yes, a warmer ocean leads to a warmer atmosphere. It does not just radiate it to space.

      • However it is eventually all radiated to space. I think you’re missing the point. With ice, the heat is trapped in the ocean. Without, its released to the atmosphere where it is radiated to space.

        This is why its not intuitive (to me) that decreasing ice leads to a positive earth energy feedback and I would say that the suggestion that decreasing ice = positive feedback as an “obvious intuitive result” simply means its not been thought through because it needs careful measurement to justify.

      • TTTM, if anyone is still on this thread, reducing ice will reduce albedo leading to more energy in the earth system overall. This is what leads to net warming. The point is taken that this also makes the polar regions more efficient at losing heat, so we have more heat in and better loss of heat by polar regions. This latter effect would only affect the warmer temperature’s distribution, allowing more of the warming to remain in the polar regions, in my opinion.

      • “This latter effect would only affect the warmer temperature’s distribution, allowing more of the warming to remain in the polar regions, in my opinion.”

        Everyone is entitled to an opinion. Some people have better intuition about their opinions than others but at the end of the day no-one’s opinion is science.

        The only thing that is certain is that “ice loss leads to warming” based on decreased albedo alone is one of those “less considered” opinions and should never be put forward as an “obvious truth”.

      • The Earth loses energy as a negative feedback all year around anyway, in which the loss is constrained by the enhanced greenhouse, the importance of the albedo is how much solar is absorbed by either new greenery, open ocean, or the newer slick darker ice. Also, ocean takes up most of the energy in the short term in the upper layers and some is moved below into deeper ocean. This is why we will not experience the entire warming from the energy imbalance as a fast response.

      • The only thing that is certain is that “ice loss leads to warming” based on decreased albedo alone is one of those “less considered” opinions and should never be put forward as an “obvious truth”.

        This has nothing to do with “intuition”. Where are you getting that from? It based on physics, known physics going back a long time, including working out heat fluxes, balance of energy reflected and absorbed, cloud cover, etc. I was going to cite an example, but the amount of information I received from a simple ‘Google scholar’ search on “physics albedo climate” was overwhelming. I’d suggest you look into the basic physics before accusing people of using their intuition when describing well established science theory, backed by reams of evidence.

      • And how does a search on “physics albedo climate” find the resulting outgoing radiative changes due to the increasingly open ocean?

        For example, if you look at the NSIDC website that describes incoming solar radiation’s effects in the Arctic, there is no mention of increased outgoing radiation at all.

        http://nsidc.org/arcticmet/factors/radiation.html

      • Oh…and regarding your question of “intuition”, Chris specifically mentioned it in his post which started all all this.

        “Some of them are very intuitive (less ice over a better absorbing surface means solar absorption is enhanced) “

      • For example, if you look at the NSIDC website that describes incoming solar radiation’s effects in the Arctic, there is no mention of increased outgoing radiation at all.

        Your own citation gives you the equation you are looking for.
        S(down arrow)(1-alpha) + (Lup-arrow + Ldown-arrow)

        S(up arrow) is incoming solar radiation, alpha is surface albedo, L(down arrow) is downwelling longwave radiation (thermal infrared radiation emitted from cloud bases and atmospheric gases), and L(up arrow) is upwelling longwave radiation (thermal infrared radiation emanating from the earth’s surface).

        The basics are, 1. Earth is taking in more energy because of less reflective surface area and more absorbing area. 2. The longwave radiation (of which there is more of) that emits upwards is absorbed and emitted by increased greenhouse gases.

        You seem to be suggesting that because the Earth is taking on more energy, the Earth is losing more energy, and the extra energy is mitigated this way somehow. But even at stable greenhouse levels, energy is kept within the system by absorption of ocean, land, and water vapor, CO2, clouds, etc. It’s what keeps us from being like Mercury. By what physical process do you think would make your suggested reality possible?

        Just to get you started, at thermal equilibrium, the emissivity of a body (or surface) equals its absorptivity. (Kirchhoff’s law of thermal radiation)

      • TTTM,
        Judith Curry has done extensive work in this area, especially the in arctic clouds, which would be a possible reflecting mitigator if it happened in other areas besides the arctic. She should be able to answer some of these questions you have. You should start a thread like this in the open thread and hopefully she will get to it.

        If not, here is one of the papers I found, along with another paper that cites her work

        http://lightning.sbs.ohio-state.edu/geo622/paper_ice_Curry1995.pdf

        http://www.gfy.ku.dk/~kaas/forc&feedb2008/Articles/Vavrus.JClim.2004.pdf

      • Very interesting and informative exchange about things I’ve been reading about.

        Worth rereading each message carefully.

      • “Your own citation gives you the equation you are looking for”

        Giving an equation isn’t the same as acknowedging the feedback from increased ocean…which it specifically doesn’t.

        What it does say in the Arctic Energy Budget section (check out the diagram) is “”O” represents the flux of heat from the ocean to the atmosphere through openings in the ice (leads and polynyas). ”

        Leads and Polynyas eh? What about increasing open ocean?

        I guess they dont want to confuse the punters. Afterall by suggesting there are both positive and negative feedbacks the average punter might wonder which dominates. Why confuse them when there is a perfectly good meme out there saying ice loss is a positive feedback…no extra thought required…

      • gyposaurus:

        This has nothing to do with “intuition”. Where are you getting that from? It based on physics, known physics going back a long time, including working out heat fluxes, balance of energy reflected and absorbed, cloud cover, etc.

        Based on all of that aye? Why not test your knowledge?

        I see mention of dark surfaces being better absorbers but no mention of being better emitters (Kirchhoff’s Law). There are places where a lot of ice has been lost for example Mt Kilimanjaro do you think you can demonstrate that it’s warmer up there than it would have been had the ice not sublimated away?

      • “The key support for climate sensitivity estimates is Earth’s history, although we have a strong basis of observational support for individual feedbacks such as the water vapor feedback… (see Knutti and Hegerl, 2008 for a review that is still pretty up-to-date).”

        Link to Abstract. Full article is paywalled.

        Reto Knutti & Gabriele C. Hegerl, “The equilibrium sensitivity of the Earth’s temperature to radiation changes” (Review). Nature Geoscience 1, 735 – 743 (Oct. 2008), doi:10.1038/ngeo337

      • For full paper without paywall: http://www.gfdl.noaa.gov/cms-filesystem-action/user_files/ih/papers/knutti_hegerl.pdf

        A hint for people looking for non-paywalled versions of papers. Use Google Scholar to search for the paper initially. You may get only the original site as a primary hit (I did with this one). But at the end of the hit reference is a link that says “All 7 versions”. Click on this and usually you will find that one or more of the authors has the paper on their institution’s website, without the paywall.

      • Of course, I meant in that particular case the link says “All 7 versions”. Obviously the number will vary.

      • Hi Chris,
        Thanks for the reply. I appreciate the tone of this converstaion a great deal. My follow-on question is: in a world with feedback, can anything be taken as intuitively obvious?
        Also, my comment about “by definition’ concerned the CO2 curve. Any part of the curve to the left is by definition steeper than any part to the right (true?). My question then is: why would anyone believe things will get worse with increasing CO2 concentrations? Since the curve is flatter, shouldn’t the effects of increasing CO2 be less extreme?

        Chip

      • Finally, more pertinent to climate change than “CO2″ is the total forcing (CO2 +aerosols +methane+natural factors like sunlight, etc).

        You could be more misanthropic about it by substituting the word “raping” in lieu of “forcing”.

  10. Willis Eschenbach

    Chris Colose | November 15, 2010 at 1:18 am

    Willis, your argument basically boils down to “if it’s hard to understand, we minus well wave our arms in the air and call it a lost cause.” Sorry, but scientists have to move away from freshman-level stuff eventually and understand complex systems. Just because you don’t know the biological processes that act to regulate body temperature, doesn’t mean biologists don’t. Your arguments allows for denial of any conceivable evidence on the grounds we don’t understand everything. This is just not convincing.

    Say what? I say that complex systems often do not respond to forcings in nice neat linear predictable ways. Your response is that biologists know about body temperature regulation, and that my arguments allow for the grounds of denial of evidence on the grounds we don’t understand everything … which of course, I never said. In fact, I didn’t say anything like that at all, you are simply making things up. This is a most revealing tactic, since it reveals that the person making things up is not really interested in a scientific discussion.

    Yes, Chris, I know that biologists understand temperature regulation. But that is immaterial to my point. Complex systems in general do not respond linearly to forcings. If you have any evidence that the climate responds linearly to forcings, bring it out and let’s discuss it. Because I know of none. Yes, models seem to respond linearly to forcings … but I’m looking for evidence, not models.

    • @-Willis Eschenbach
      “Complex systems in general do not respond linearly to forcings. If you have any evidence that the climate responds linearly to forcings, bring it out and let’s discuss it. Because I know of none. ”

      You are right, there are feedbacks that amplify the effect of any forcing as seen by the ice-age to interstadial transition. The variation in insolation from the Milankovitch cycles is very small – comparable to the energy change from rising CO2. It is the complexity of the climate system that amplifies that small change because of changes in ice-cover affecting albedo and rises in CO2.

      This is part of the argument over climate sensitivity. We know the climate response is not linear from past climate change, it shows feedback responses that amplify it. If that climate sensitivity is very low then climate variation would be very small, the LIA and MWP period would be imperceptible.
      The fact that small variations in volcanic emissions and solar output can make measurable alterations in climate is clear evidence that the sensitivity is high, and there is no reason to assume that non-linearity will fail to operate in response to the extra energy from the rising atmospheric CO2.

      • Izen
        Your remarks on climate sensitivity are very interesting and have caused me to pause and reconsider my (mildly) skeptical position. Do you think this is what Judith has been trying to achieve?

        PS I think (anecdotally) that activity on the some of the skeptic blogs is down – everyone is here!!

      • Yes, izen, this is something I have tried to emphasize in posts here and elsewhere. Doubling CO2 has seven times the forcing of the estimated solar increase coming out of the Little Ice Age. Yet, while people happily accept the LIA and MWP, they don’t realize the relative magnitude of the forcings, regardless of feedbacks. CO2-doubling is not a small thing compared to solar variation, it is much more significant.

    • Willis I’ve been trying to find the original reference to biologists and temperature regulation – did you make it?

      • Is this what you seek?
        CC may have conflated today´s exchange and the example from WE´s link.
        ………………………………
        Chris Colose | November 15, 2010 at 1:18 am |
        Willis, your argument basically boils down to “if it’s hard to understand, we minus well wave our arms in the air and call it a lost cause.” Sorry, but scientists have to move away from freshman-level stuff eventually and understand complex systems. Just because you don’t know the biological processes that act to regulate body temperature, doesn’t mean biologists don’t.

        Thank you, Judith

    • Yes,
      Colose is time-wasting and misleading by arguing that “climate is complex” is the same as “body temperature regulation”.

      Everytime anyone articulates a clear statement of ‘state of knowledge/ignorance’, you are likely to find a science activist brandishing the ‘are you implying that we climate scientists dont’ know anything, refutation-from-complexity’ argument.

      Grow up and stop playing word games, guys – if someone says ‘climate is complex’, as Willis did in this case, it is only to say: a certain level of certainty is not possible at the moment about certain things, which in turn do affect our overall understanding.

    • Willis

      I don’t think you understand what you are saying. Chris’ summary is right. It appears to be more a case of your not being able to understand the evidence provided for AGW that you cannot be convinced it is real. Instead you just wave your arms about there not being, evidence for lack of anything better to do.

      It is because there is not a neat linear response that we have to rely on the models for our best understanding of the response of the climate to increased CO2. They do consider a variety of forcings, including changes in ice coverage and vegetation changes. They do not just respond in a simple linear fashion.

      Your demand that we have something other than models is just petulance. That is what we have.

      If you only want to look at the evidence, the temperature record is there, as is the changing cryosphere. There is biological evidence like crop planting areas, where crops are no longer viable in areas that are now to hot, but viable in areas that were once too cold.

      • Willis Eschenbach

        snide | November 16, 2010 at 1:04 am

        Willis

        I don’t think you understand what you are saying. Chris’ summary is right. It appears to be more a case of your not being able to understand the evidence provided for AGW that you cannot be convinced it is real. Instead you just wave your arms about there not being, evidence for lack of anything better to do.

        Again I ask, if there is a statement of mine that you think is wrong, quote it. I have no idea what you are referring to above, it is solidly vague.

        It is because there is not a neat linear response that we have to rely on the models for our best understanding of the response of the climate to increased CO2. They do consider a variety of forcings, including changes in ice coverage and vegetation changes. They do not just respond in a simple linear fashion.

        Your demand that we have something other than models is just petulance. That is what we have.

        No. We have evidence. Physical observations. History. “Natural Experiments”. What we don’t have is an underlying theory to make sense of it.

        My issue is not with models. I first programmed a computer 47 years ago, I’ve written models myself. I know models inside and out, I know that “all models are wrong, but some models are useful”, and I use them frequently.

        To be useful, however, a model must be a sufficiently accurate representation of the real world. I think that the underlying paradigm used by the models is incorrect, and I detail the reasons why here. (Again, if you disagree with what I say in that piece, please quote what you disagree with.)

        If you only want to look at the evidence, the temperature record is there, as is the changing cryosphere. There is biological evidence like crop planting areas, where crops are no longer viable in areas that are now to hot, but viable in areas that were once too cold.

        Your lack of a quotation leaves me in mystery as to what you are objecting to. It sounds like you believe I don’t think the world generally warmed over the last century, which I certainly have not said. Please quote what I said that you disagree with, so I can tell what this last paragraph is referring to.

        Thanks,

        w.

      • Willis, with all due respect to your WUWT pieces…

        I have this issue where my mother calls me sometimes, and I’d like to think of myself as a good son, but on occassion she ends up rambling for minutes on end about nothing and I end up not comprehending a word. I have looked at two WUWT pieces that you have referenced so far, on control feedback systems and now this, and I’m not sure anything you’re saying even involves a scientific reply, as much as a statement that you’re not saying anything relevant to how scientists build up to acquire knowledge, climate or the process of climate modeling. You’re saying a lot of words about “complexity” and “non-linearity” and now tropical thunderstorms but you’re not actually saying a word about issues with the scientific process in climatology, or being specific about examples in the refereed literature that converge to show evidence for anthropogenic climate change, and why I should be convinced it’s not robust.

      • Willis Eschenbach

        Thanks for your thoughts, Chris. I take it that there is obviously nothing significant in either of my WUWT pieces that you disagree with. Because if there were, surely you would have quoted it as I requested, and told me what was wrong with it.

        You note that I’m not saying anything relevant to a host of topics like “how scientists build up to acquire knowledge” and “about issues with the scientific process in climatology”. Yep. You’re right. I’m wasn’t writing about those things there. They weren’t the topic of the posts. I love it when people want to tell me what topics I should write about.

        Finally, please accept my profound condolences regarding your inability to comprehend your own mother. It must be a burden.

      • All thermodynamic systems in nature are flow systems (i.e. live, non-equilibrium systems), and they all have configuration. If they do not have it, then they acquire it, in time. The generation of configuration is ubiquitous, like other phenomena covered by other ‘laws’ in physics. Biological systems are configured. Geophysical systems are configured. Engineering and societal systems are configured. The configuration phenomenon unites the animate with the inanimate.

        Wakalixes makes it go!

      • snide – The argument is that models are “what we have” is irrelevant. The question is, are they adequate to the task of prediction of climate? If they are not, they are not and shouldn’t be used in any way to make civilization-changing decisions.

      • Are they really used that way? Citation needed.

      • Also, I’d like to have the reason why models **must** be adequate for prediction of climate.

        Just having an idea of what “predicting the climate” looks like would be nice.

  11. The obvious difference between the FAR and the present is the comment –
    “Global – mean surface air temperature has increased by 0.3°C to 0.6°C over the last 100 years, with the five global-average warmest years being in the 1980s. ”
    In the two decades since then the 90s were warmer than the 80s and the last decade warmer than than the 90s, the warming has continued, and attribution to CO2 has become much more certain.

  12. These statements are still mostly fairly close to current understanding, although a few things like the degree of warming so far need updating. One thing that strikes me is the exclusive emphasis on greenhouse gases. Some anthropogenic influences on climate that have gained more prominence since the FAR seem to deserve a mention. I am thinking particularly of the role of aerosols, soot and land use change, all of which we have better knowledge of than at the time of the FAR. Also we understand somewhat better the role of CFCs in the production of ozone.

    Finally, I note that there is no mention of clouds, or albedo in general, in determining the direction and strength of climate change. Clouds are the big unknown factor (AFAWK :-)) in the area of feedbacks.

  13. Here I show two sets of data: the Central England temperatures-CET and the ‘North Atlantic precursor’ – NAP.
    http://www.vukcevic.talktalk.net/LFC-CETfiles.htm
    You might be surprised to know that the NAP data, for number of reasons is far more certain than the CET data, but it is totally ignored by the climate science, although has all attributes necessary to have a substantial effect on the climate of the North Atlantic basin.

  14. Let me suggest that water vapor should also be added to the list of “emissions resulting from human activities” that are “substantially increasing. ” Since 1950 man-made sources of water vapor have expanded dramatically–expansion of agriculture in formerly arid and desert locales, acres of swimming pools in S. California, open aqueducts, expansion of rice farming, and the like. Maybe there’s a good reason to exclude anthropogenic water vapor from the discussion, but I’ve made a modest effort to find it and couldn’t.

    .

    • Hi Mike

      Have you ever compared the area of the oceans with the area of the swimming pools? I think you will find that oceans are VERY VERY BIG. And even the most ostentatious Californian swimming pool is very very very tiny by comparison. :-(

      BW LA.

      (Capitals not to shout, but to emphasise my point about relative size)

      • Latimer,

        Thanks for the reply and education. Still a nagging thought though. If CO2 is only providing a small increase in temperature, in and of itself, but is, of concern, due to an amplification of that small temperature increase by feed-back with water vapor, then wouldn’t the same concern attach itself to a water vapor as a source of small, incremental warming? In other words the same worrisome amplification of a small incremental warming, would be triggered by any source of GHG warming, to include water vapor, wouldn’t it?

        I’m in way over my head, Latimer, and I know I’m dealing with some of the finest scientific minds in the world, to include yourself. But if I may be so bold, could I respectfully ask for some more of your valuable time to explain this issue just a bit further?

        But thank you kindly, again, for your previous reply.

      • Mike

        I would be happy to explain it if I could. But I can’t. The same thought struck me a few hours ago as I was contemplating these mysterious feedbacks.

        The way I describe it to myself is more like physical chemistry.

        It seems that it is believed that CO2 acts like some form of a ‘catalyst’ (OK, OK – I know the analogy is not exact – I did reaction kinetics for my Masters :-) ) which sets off a much greater temperature increase due to water vapour than would otherwise occur. Or maybe like a detonator in an otherwise stable mixture…it gives the final push that sets off the big bang.

        But this ‘feedback’ has some very mysterious properties. It has no sound theoretical basis in physics afaik. And it is self-limiting. Somehow a heated water molecule ‘knows’ whether it was heated by heat caused by carbon dioxide – in which case it will carry on heating up – or if it was heated by heat because of the warming of the much more abundant water vapour all around it. In which case it says ‘halt’, and stabilises its temperature. But only when it has caused Nearly Catastrophic Anthropogenic Global Warming – or so we are led to believe.

        You or I might think that this all sounds like a considerable load of hooey, and my physical chemistry/kinetics nostrils are twitching a bit.

        But it is climate science we are investigating here. And stranger things than this happen in climate science. The principle of ‘Teleconnections’ asserts that selected trees respond to climate changes thousands of miles away, but are unaffected by local conditions. This is a form of telekinesis that has not been observed in any other field.

        Years ago, I studied Quantum Mechanics. Which is very very strange. A strong character in this tale is Schrodinger’s Cat, whose existence (or non-existence) only becomes apparent when somebody looks for it (Yes, again, I know that this is a simplification). When nobody is looking the Cat is neither dead nor alive…..which is pretty counter0intuitive – as is all of QM.

        Climate science is a bit like this. Full of phenomena that are only observable to ‘peer-reviewed Climate Scientists’. When mortals or statisticians or chemists or engineers or IT guys go looking for the same effects they disappear. As does the raw data, the programs that saw the effect, the history of ‘adjustments’, and more gigajoules of heat than you could use to build a travesty with. But it must be true because ‘peer-reviewed Climate Scientists’ tell us so.

        Funny Old World innit?

      • Latimer,

        Wow, that was a great reply! Now time for me to retreat to my “lurker” corner, except to say, if no can justify keeping anthropogenic water vapor off the list of GHG , then it would appear that it should be included.

        Again, thank you so much, Latimer.

        Mike

      • Anyone interested may find amusement in a recent tale over at WUWT where Anthony’s New Cat (Mega Watts – ouch!) went missing over the weekend…causing sleepless nights for several observers. Happily now restored to the bosom of his loving family.

        It seemed he had tunnelled into a drawer smaller than himself. Which proves that maybe quantum mechanics has some basis in everyday life after all :-)

      • Short answer: It Rains.

        Longer version: The residence time of water vapour in the atmosphere is very short (~3 days), so any excess over equilibrium would simply fall as rain before it had a chance to heat the planet.

      • Andrew,

        Thank you for your reply. Greatly appreciate it. If you don’t mind, I’d like to explore your response a bit more. My likely misguided thought is that while anyone water vapor molecule may spend no more than 3 days or so in the atmosphere, if another molecule promptly takes its place from an anthropogenic source, then isn’t there a “steady-state” of water vapor with an anthropogenic warming potential? In that regard, once a rain fall flushes out the water vapor in the atmosphere, doesn’t the water vapor simply reappear when the sun comes out?

        It is also puzzling (due to my ignorance, I have no doubt) that water vapor can be such a powerful forcing agent on the one hand, but then ignored in the consideration of anthropogenic GHG, on the other hand, since water vapor rains out of the atmosphere before it can produce heating.

        My further best efforts to figure out water vapor as a source of warming is that anthropogenic sources of water would have little additional warming effect if the atmosphere in a given locale is generally saturated with water vapor from natural sources to its fullest potential. But in more arid locales, anthropogenic sources of water vapor from agriculture, combustion by-product, aqueducts, watered-lawns, swimming pools, etc. would provide for an in crease in the average amount of water vapor in the atmosphere with an attendant warming effect, wouldn’t it?

        This has been a puzzling issue for me and exceeded my amateur powers of analysis. Andrew, could you help me get a handle on this matter since I’m developing something of an uncomfortable obsessive/compulsive curiosity about it and haven’t been able to find a clear explanation aimed at my level (which is pretty much the Scientific American level).

        Thanks again for your last reply and any time you might spend responding to this comment.

      • Of course, if anyone else wants to help out with an answer, that would be much appreciated, as well.

      • Hi,

        Although mankind is producing a steady stream of water vapour, because is rains out almost immediately, the concentration-over-equlibrium remains small. Like filling a bucket with a big hole in the bottom..

        Wheras with CO2, the ‘hole’ is very, very small.

      • Thanks, Andrew. I’m getting there, but one more question please. I think I understand the bucket analogy in terms of the long-term build up of CO2 vice water vapor with a future potential for increased AGW (assuming CO2 induced warming does not plateau beyond a certain concentration) in proportion to that CO2 build-up.

        However, isn’t the more short term behavior of water vapor perhaps better illustrated by a bucket without a hole in the bottom that “fills-up” with water vapor until it overflows? And if the above sort of bucket is normally only partially filled with water vapor, such as in arid/desert locales, for example, won’t the man-made creation of new water sources in such locales (the laundry list of the previous comment) further fill the bucket within the limits of its rim. If so, then it would seem that a net increase in atmospheric water vapor would be realized from anthropogenic sources and hence increased anthropogenic warming from water vapor.

        I suspect I have something cock-eyed, please help straighten me out. You’ve spent a lot of time on my education, Andrew. Thanks again.

      • Actually mike, your description is pretty accurate, except that in the context of dry desert regions there are dynamical rather than thermodynamical constraints on the climatological-mean water vapor content. If you’re under the wings of the descending branches of the meridional tropical circulation, for instance, as you move out of the tropics then your air is going to be pretty dry (actually the isentropic transport by midlatitude eddies plays an even large role in setting the dryness of the subtropics, moreso than the direct diabatic descent of air from the outflow of the Hadley circulation).

        Direct anthropogenic inputs of water vapor is only relatively small in terms of forcing; the argument for a positive water vapor feedback is simply a statement that the specific humidity will rise in the upper troposphere in a global warming scenario, a suggestion seen not just in models but in observations and a number of studies examining the distribution of water vapor in the atmosphere (see my post on this here) and the Dessler and Sherwood review paper last year.

        It’s important to note that it is often said “the hydrological cycle will be more intense” in a warming climate. I’m not exactly sure what that is supposed to mean, but it’s worth keeping in mind that the fractional changes in water vapor content as the globe warms exceed (by at least a factor of 2 or 3) the fractional changes in water vater vapor sources to the atmosphere (i.e., evaporation, and correspondingly, the precipitation). In a sense that actually means the water vapor cycling in the atmosphere becomes more sluggish as the globe warms. Note also that the spatial distribution of these changes is much more heterogeneous than the temperature change, with some regions becoming wetter and some drier.

      • Direct anthropogenic inputs of water vapor is only relatively small in terms of forcing; the argument for a positive water vapor feedback is simply a statement that the specific humidity will rise in the upper troposphere in a global warming scenario,

        The word ‘bubble head’ (vapor lock, inversion) comes to mind here.

      • Chris,

        Thanks, I think I’ve got it now. Greatly appreciate your reply.

        Mike

      • Dismissing your query by suggesting that swimming pools are puny compared to oceans misses at least part of what may be an important question.
        An enormous reservoir in Egypt, another in China, another on the Columbia, TVA-built lakes, every gated community with several golf courses bordering lakes, flood-control impoundments: we store even more water than C. canadensis.
        I think your inquiry deserves more study: grant-writers, Alert.

    • I think you forgot H2O emissions from burning hydrocarbons. It is new water formed by oxidation of Hydrogen from HC.

  15. Re: Izen, Willis, and interested parties on “non-linearity”

    There’s been sufficient references to non-linearity, complexity, and positive feedbacks on this thread so far to make some notes about it. I want to to do this since the terminology is starting to get technical, and we’re probably saying things that other people may interpret as something else, and clarification may be of interest to readers to sort out these arguments.

    The first issue, which steve mosher described well, is if we take a CO2 forcing and make everything else equal, the temperature is mandated to rise. This is because the optical depth τ (which is the negative of the logarithm of the transmissivity of the air column) increases, resulting in the whole planet radiating less energy to space (since the vertical temperature gradient of the atmosphere results in absorption line features). The only way to get back to radiative balance is to increase the area under the curve of a Planck-like distribution, meaning T must rise. The first issue of “complexity” is of course to determine whether CO2 is the only forcing we’re interested in. Clearly if we double the CO2, but turn off the sun, the planet is going to cool down by a similar type of reasoning described above. As such, it is important to understand all forcings (natural+anthropogenic) and not to dismiss either without actual observations and quantification. The so-called “radiative forcing” provided by the well-mixed greenhouse gases is relatively easy to calculate, and good agreement exists between detailed line by line radiative transfer codes and GCM’s.

    The question naturally arises to what extent are forcings expected to change in the future. On the anthropogenic side, this is clearly a socio-economic issue, but to the extent that air pollution doesn’t increase dramatically it seems reasonable to suggest aerosol effects won’t change significantly, or even decline in importance, as is reflected in surface brightening trends over much of the globe (with the exception of China, possibly some other territories like India but I’d have to look this up). On the natural side, long-term observations of the sun show that its changes are very small relative to the type of forcing expected from a doubling of CO2. Volcanoes are important but are only very pronounced on the short-term. The Holocene provides good evidence that the climate is generally stable (to within +/- 1 degree) with respect to non-anthropogenic and minimal anthropogenic forcings since the last glaciation. Thus even if we move into a Maunder-Minimum type of situation, this is expected to only offset anthropogenic warming by a few tenths of a degree, and more importantly will not do so indefinitely. The CO2 we emit today has full potential to impact climate for hundreds and even thousands of years.

    Armed with knowledge about what appears to be a generally stable climate without forcing (a feature also seen in models), we can ask how this situation might change as you move to glaciation or to a 2xCO2 world, that brings us to “complexity.” A key question here is whether the forcing provided by the well-mixed GHG’s is sufficiently strong to overcome the possible sensitive dependence to initial conditions (chaos effects) that may lurk in the climate system on decadal to millennial time-frames. The working hypothesis from observations and modeling is that even if some sort of chaotic effects such as this exist, the trend induced by a sufficiently strong and persistent radiative forcing will overcome the sensitive dependence to initial conditions. No coupled simulation for example of Holocene-like conditions abruptly creates climate changes as large as a doubling of CO2, which is borne out in observations of the magnitude of Holocene climate evolution.

    Now it may be that doubling CO2 spontaneously triggers some “tipping point” which no model includes, as may have been the case with D-O events in the past during glacial times, but it’s of course not possible to make much sense of these “what if” cases that have no paleo-analog and no suggested mechanism for what they might be. I The types of abrupt climate shifts seen during the last glaciation do not occur in warm regimes where you don’t have much ice. t is of course possible to enter a new climate state, such as one with a summer-free Arctic or no Amazon, that is not readily reversible even if CO2 concentrations were magically set back to pre-industrial. The IPCC concluded that it wasn’t very likely (<10%) of a THC shutdown for example this century. Though, the prospect for these "tipping points" many would argue should be included in policy risk assessment, but I don't have much opinion on this point. An NRC report several years ago on Abrupt Climate Change engages this topic thoroughly.

    Clearly examples of non-linearity are seen in climate. It's probably not big if you confine your model to the atmosphere and slab ocean, but if you start to include ocean dynamics you get ENSO which clearly falls under the type of behavior Willis eludes to, losing predictability on the order of years. In fact, ENSO behavior is a big question in future climate projections. This does have influence on the year-to-year patterns in climate and can potentially be a big player for global or tropical mean temperatures in particular years, but there's no suggestion that its behavior could radically change as to significantly affect a radiative-induced trend.

    Finally, while I agree with Izen that positive feedbacks seem to be robust results on the timescales of consideration, this is not synonymous to saying the climate displays intrinsically non-linear responses to forcing. The working definition of net positive feedbacks in climatology is simply that the final temperature response is greater than the no-feedback Planck radiative response alone, which is about a quarter degree C per (W/m2) forcing, with very little uncertainty. However, under the relatively small changes in consideration, the temperature response is thought to respond linearly to the forcing (Knutti and Hegerl, 2008 discuss this in detail).

    A large part of the recent Zaliapin and Ghil (2010) paper is that abrupt jumps due to non-linearity don't occur unless the system is awfully close to a bifurcation point (as in the canonical f=1 limit that roe and baker have popularized). This might happen if the ice-line reaches a critical latitude to make a Snowball Earth a stable solution to given solar and greenhouse parameters. As Roe, 2009 has pointed out, feedbacks behave intrinsically like Taylor Series, and the first term of a Taylor series is a linearization term; of course, in the f=1 limit you need higher order terms to tell you what happens.

    • “The so-called “radiative forcing” provided by the well-mixed greenhouse gases is relatively easy to calculate, and good agreement exists between detailed line by line radiative transfer codes and GCM’s.”

      What? Could you please clarify here?

      A GCM innately does not know what do with a greenhouse gas, does it?

    • Willis Eschenbach

      Chris, thanks for your response. You say:

      Chris Colose | November 15, 2010 at 4:38 am | Reply
      Re: Izen, Willis, and interested parties on “non-linearity”

      There’s been sufficient references to non-linearity, complexity, and positive feedbacks on this thread so far to make some notes about it. I want to to do this since the terminology is starting to get technical, and we’re probably saying things that other people may interpret as something else, and clarification may be of interest to readers to sort out these arguments.

      The first issue, which steve mosher described well, is if we take a CO2 forcing and make everything else equal, the temperature is mandated to rise. This is because the optical depth τ (which is the negative of the logarithm of the transmissivity of the air column) increases, resulting in the whole planet radiating less energy to space (since the vertical temperature gradient of the atmosphere results in absorption line features). The only way to get back to radiative balance is to increase the area under the curve of a Planck-like distribution, meaning T must rise.

      That’s where we part company. You are in the fallacy of the excluded middle. There are at least two other possible ways to bring the system back into balance.

      One way to bring the system back into balance is to decrease the incoming energy. This is seen every day in the tropics as temperature increases. Above a certain temperature, clouds form, and reduce the incoming energy by tens of w/m2. If the average cloud cover of the earth increases only a few percent, it totally negates the increase in forcing from a CO2 doubling, restoring the balance.

      The second way to bring the system back into balance is to increase the efficiency of the heat loss mechanisms. This occurs in a variety of ways, principally via thunderstorms which move huge amounts of heat to the upper troposphere, where it is free to radiate to space or to move poleward. Once again, the radiative balance is restored.

      This is a perfect example of what I mean about complex systems. There are always more possibilities than you imagine. And to bring that back to the topic of the thread, that is why we lack certainty about many aspects of the climate.

      • Willis Eschenbach

        See if I have this right: Prince Charming and Prince Gallant will ride in on a fluffy white cloud and a thunderstorm and save us all from our wicked CO2-emitting dragon?

        Our certainty that these princely negative-feedbacks are going to dominate or even come to a similar order of magnitude to the positive feedbacks comes from our Fairy Godmother’s wand?

        For any complex enough system, one can fabricate or inflate plausible-sounding emergent effects endlessly. They may even exist, on some intermittent pattern, in some narrow range of responses, or on some very tiny scale. They’re little footmen who turn into little white mice at midnight and scurry away.

        Even if they are persistent large-scale effects, how is disturbing the climate with huge shifts in cloud cover and storm increase a good thing, again? Do the tropics really need more intense and frequent storms on a longer storm season with a wider storm creche? Because that’s what your feedbacks amount to, isn’t it?

      • Bart R, you just stepped over the line from “what’s the science consensus” to meeting the needs of the planet.

      • I have zero interest in consensus, as anyone ought be able to tell.

        Also, I’m pretty sure there’s a consensus that I stepped over the line a long time ago.

        However, if you want it said inside the box, I claim that all anthropogenic thermomechanical disruptions — whether temperature feedbacks or not — unless they are also completely nugatory of anthropogenic forcing effects — remain disruptions still, and anthropogenic still, and ought be examined for potential danger still.

        I call tropical cyclones, which are part of the growing group of clouds and thunderstorms, potentially dangerous. This ‘negative’ feedback is storm-seeding in an already demonstrably more hurricane prone climate. It’s shoot-yourself-in-the-foot salvation.

      • Willis Eschenbach

        Bart R | November 15, 2010 at 10:28 am

        Willis Eschenbach

        See if I have this right: Prince Charming and Prince Gallant will ride in on a fluffy white cloud and a thunderstorm and save us all from our wicked CO2-emitting dragon?

        See if I have this right: you would rather trivialize and divert the discussion with nonsensical fantasies than deal with the science.

      • Willis Eschenbach

        I was openly proclaiming by my manner and words that your argument has the appearance to me of nonsensical fantasy, which I would certainly rather not see when dealing with science.

        Not everyone can do the mathematics, estimation, approximation, recognize the Chaos-Theoretical implications, visualize the broader picture offered by these cloud and storm mechanisms.

        I contend you have a long way to go before you convince me you have this aptitude sufficient to support the claims you make.

        By all means, please feel free to demonstrate otherwise.

        There is nothing I love so much as to learn.

      • Willis Eschenbach

        Bart R | November 15, 2010 at 10:33 pm

        Willis Eschenbach

        I was openly proclaiming by my manner and words that your argument has the appearance to me of nonsensical fantasy, which I would certainly rather not see when dealing with science. …

        No. You were openly proclaiming that rather than point to a single scientific error I have made, you would rather make a puerile and pathetic attempt to mock me.

        If you think I am wrong in some scientific claim that I have made, then quote exactly what I said and let me know exactly where it was wrong. Anything other than engaging on the science is just onanistic self-amusement on your part, childish mockery which you likely find hilarious but which is far less amusing when viewed from this side.

      • Specific scientific error; “possible ways to bring the system back into balance,” must be possible, which I grant both your examples are, but also must bring the system back into balance, which appears to my mind to conflict with the Second Law of Thermodynamics.

        Can you demonstrate how your scenarios do not violate conservation of entropy, on whatever scale you choose?

        Saying the temperature won’t go up because the Thermomechanical Principle requires some of the heat to be turned into mechanical power doesn’t reduce the impact, it turns it from warming with smaller negative feedback into storming with larger negative feedback in the short term… which is to say, it increases dangerous weather.

        Even if we never get any warmer temperatures, getting permanently stormier is by no means a solution.

        External forcings disrupt complex systems incrementally. While the forcing persists, the chaos of the system continues to increase; I believe this is a precept of Chaos Theory.

        Am I anywhere near close?

      • Willis Eschenbach

        Thanks, Bart. My answers follow:

        Bart R | November 16, 2010 at 12:02 am
        Specific scientific error; “possible ways to bring the system back into balance,” must be possible, which I grant both your examples are, but also must bring the system back into balance, which appears to my mind to conflict with the Second Law of Thermodynamics.

        I’m sorry to hear that … but until you detail and demonstrate the conflict, I feat that’s not too helpful.

        Can you demonstrate how your scenarios do not violate conservation of entropy, on whatever scale you choose?

        Sure, I’d be glad to. First, if you wouldn’t mind, could you demonstrate that your solutions do not violate “conservation of entropy”? That way I’ll know what kind of demonstration you are looking for, and I won’t waste everyone’s time with a demonstration that you won’t accept.

        While you are at it, a definition of “conservation of entropy” would be valuable … as far as I know, entropy is generally increasing and is not conserved.

        Saying the temperature won’t go up because the Thermomechanical Principle requires some of the heat to be turned into mechanical power doesn’t reduce the impact, it turns it from warming with smaller negative feedback into storming with larger negative feedback in the short term… which is to say, it increases dangerous weather.

        Even if we never get any warmer temperatures, getting permanently stormier is by no means a solution.

        Fortunately, we have reasonable data on this one. The earth has been warming for about 300 years, and warming rather quickly in two pulses in the 1900s, one in the first half of the century and one in the second half.

        However, there is no evidence of increasing storminess over those periods of warming, whether of gales or hurricanes. And lots of people have looked for it. So your theorizing doesn’t fit historical observations.

        External forcings disrupt complex systems incrementally. While the forcing persists, the chaos of the system continues to increase; I believe this is a precept of Chaos Theory.

        I’m sorry, Bart, but I have no idea what you are trying to say here.

        Am I anywhere near close?

        Better. It would help if you would be more specific about exactly what I said that you disagree with, by quoting my words that you are claiming are wrong. I have no problem with being wrong, otherwise I couldn’t be a scientist and an inventor. But you need to tell me exactly where I’m wrong.

        PS- The idea that you can let off the gas to balance out a heat engine is not exactly a novel world-shaking claim. That’s all that happens with the clouds, they cut down the amount of solar energy entering the climate system to restore the balance.

        And it is trivial to note that if input and output of anything are not balanced, it is quite often possible to adjust either one to bring the system into balance … which casts doubt on your claim that clouds reducing the solar energy entering the climate system somehow violates “conservation of entropy” …

      • Willis

        That was really quick.

        Of no special use to anyone, but quick.

        I think, for now, I’ll maintain my opinions as stated, with the reasons as stated.

        But thanks for the effort.

      • If I’m not mistaken, there is no empirical support for the conservation of entropy.

      • Willis Eschenbach

        re: “you would rather make a puerile and pathetic attempt to mock me.

        Such was not my intention, and if you take it thus, I apologize.

        I intended to ridicule arguments which appeared glib and facetious with an equally — to my mind — glib parody.

        Yourself I maintain the highest regard for, and admit I learn from; I value your contribution to Climate Etc. in everything you post, though I may from time-to-time dispute the content or conclusions in their own right, with no reflection on yourself.

      • Willis Eschenbach

        Bart R, thank you for a most gentlemanly reply. I apologize for the harshness in my tone.

        I am making more general arguments here because the question is what we know with confidence.

      • Willis – Take a look at this global lightning map. It bears out what you are saying about greater energy absorbed = more active heat dissipation.

        http://www.lightningsafety.com/nlsi_info/lightningmaps/worldlightning.html

      • I’m wondering if the climate models show thunderstorm activity and, if they do, do they show the real pattern?

      • Willis Eschenbach

        Thunderstorms are far smaller than the grid size of a climate model, so models give us no information on this.

      • Richard S Courtney

        Willis:

        You say:
        “Thunderstorms are far smaller than the grid size of a climate model, so models give us no information on this.”

        I undertand what you mean (i.e. the models can only emulate effects larger than their spatial resolution), and I agree with it.

        However, with respect, I think there is a more serious issue provided by your wording.

        The climate models are – and can only be – formulations of existing understandings of the real climate. They can be used
        1. to test those understandings against empirical data,
        2. to explore the limitations of those understandings against empirical data, and
        3. to assess the possible behaviours of the climate system according to those understandings.

        But that is very different from “giving us understanding” of anything (including thunderstorms) in the real climate.

        Simply, the models are not the real climate and they emulate effects of the understandings built into them. So, the models can be used to test those understandings but cannot be assumed to indicate anything about the real climate.

        This difference is important and is not knit-picking. It is why the outputs of the models are not “evidence” of any aspect of the real climate. The model outputs are “evidence” of the understandings and assumptions built into the models.

        Richard

      • After looking into this a bit more, it appears the temperature is also as high over some of the ocean as some of the land. Maybe aerosols cause more thunderstorms over land.

  16. Dr Curry, rather than setting an exam question for your pupils here, how would *you* answer the following?

    “How have these statements held up over time? Have there been any serious challenges to these statements? Is the known ignorance associated with these statements substantial? Are these the statements that pretty much everyone can agree with?”

  17. Re ” Some of them are very intuitive (less ice over a better absorbing surface means solar absorption is enhanced) ”

    You have different intuition to me then because open water is also intuitively better at radiating heat than ice and I expect changes the convection of the water too. It seems to me that if warmer waters were flowing from the south then the Earth may lose more energy as a net result.

    • Richard S Courtney

      TimTheToolMan:

      You say:
      “Re ” Some of them are very intuitive (less ice over a better absorbing surface means solar absorption is enhanced) ”

      You have different intuition to me then because open water is also intuitively better at radiating heat than ice and I expect changes the convection of the water too. It seems to me that if warmer waters were flowing from the south then the Earth may lose more energy as a net result.”

      I agree with your intuition.

      At present the Arctic region is a net emitter of radiation because
      (i) heat energy is transported from the tropics and polewards by the oceans
      and
      (ii) there is little solar radiation received in polar regions in summer months and none in winter months (which is why these regions are cold).

      Ice is a better reflector (so a poorer absorber) of solar energy than water but there is little solar energy recieved by polar surface regions.

      And ice acts as an insulant on the surface of the water and, therefore, acts to inhibit heat loss from the water. Indeed, it prevents direct radiative heat loss from the water surface.

      Hence, complete removal of Arctic ice would have little effect on absorbtion of solar energy in the Arctic region. And it would enable greater radiative heat loss from the water.

      So, a complete loss of Arctic ice would make little change to heat gain/loss from the Arctic region, and that little change would most probably be an increase to the net radiation which – at present – is from the surface.

      Richard

      • Richard S Courtney “I agree with your intuition.”

        We might also add intuition from the curvature of the Earth and diminishing angle of incidence at polar extremes.

        Exposing darker surface might well produce a better absorber of incoming solar, but at shallow angle of incidence. Exposing a darker surface also exposes a emitter to the full hemisphere.

        Is it not therefore intuitive to conclude that ice retreat produces an enhanced cooling effect.

        The reverse may also be true – if we start with retreat beyond a critical point (local excess of cooling over incoming solar), the ice surface would be expected to advance.

        To engineers and mathematicians, this is a negative feedback loop, where the ice boundary advances or retreats in the direction of a theoretical equilibrium. (In practice we never get the luxury of observing such a theoretical equilibrium because of seasonal and other variations.)

        AGW arguments only ever present a case of receding ice cover as though it must produce enhanced warming.

      • Richard S Courtney

        Jordan:

        I agree with all you say.

        And I think it is an interesting subject for conjecture and discussion if only as an example of how real climates are local (not global) and their mechanisms are not understood with certainty.

        Richard

  18. Chip,

    I would add to Chris’ solid reply that the expectation is that global CO2 concentrations will increase for a while to come (at least in a business as usual scenario). Add to that the the climate will slowly catch up in responding fully to this climate forcing, and that negative climate forcing by aerosols may subside, and it becomes clear that the warming we may expect (at least in a business as usual scenario) will be much more than what we have experienced so far. These expectations of warming take into account what you correctly note is the diminishing return of each subsequent increase in CO2 concentration (the logarithmic effect Chris referred to).

    • “Add to that the the climate will slowly catch up in responding fully to this climate forcing,”

      Of course the world didn’t start warming in the latter half of the 20th century. It has been warming for some time now. Yet when looking at the table of attributions from the IPCC the “response to earlier forcings” catagory appears to be absent. So would you claim that there is a difference between today’s forcings and previous forcings such that only today’s has a long response time? Or would you claim that some significant portion of recent warming would be due to the long term affects of natural variability and should be attributed in that manner?

      • Steven,

        The response time depends on the timescale of the forcing: Solar insolation is strongest at noon, but the warmest part of the day is later in the afternoon.

        There is a lag in climate response to the forcing, but the *change* is strongest when the forcing is strongest; it just keeps on changing (with diminishing return, as a very slowly fading signal) for a while after the forcing has stopped changing. Thus, one cannot just assume that the warming from the seventies until the present is due e.g. to increased solar insolation between 1900 and the 1950’s, or due to the end of the little ice age in 1850. That would be the opposite of a slowly fading signal (which is what climate inertia refers to) but rather a sudden increase in signal long after the cause (the forcing) had ceased. That’s not how it works.

        Likewise, we don’t usually observe daytime temperature to be relatively constant throughout the morning and early afternoon and suddenly increase sharply at 3 or 4 pm, in response to the slowly increasing forcing (solar insolation) between sunrise and noon.

      • I didn’t say all the attribution should be placed on earlier natural variation. I also don’t see the slowly fading signal in the warming of the earlier part of the 20th century. I can only assume that the lack of a slowly fading signal at the end of the warming trend in the early part of the 20th century indicates that there was forcing left to be realised. This is of course assuming a long lag time. Perhaps it would be helpful if you indicated the lag time you think is a reasonable approximation.

  19. Dr Curry,

    “We are certain of the following” and “The main greenhouse gas, water vapour, will increase in response to global warming and further enhance it”

    Correct me if i’m wrong, but we still do not understand clouds and their relationship towards climate. So what they claim here would appear, to my simple mind, to be a downright lie.

    Am i missing something?

  20. Judith: Just a quick observation: Missing from the discussion is the simple fact that the oceans have their own “greenhouse effect”. That is, they are warmed by downward shortwave radiation to depth, but can only release heat at the surface, meaning a planet that was all ocean would have a higher surface temperature than a planet that was all land. I believe it was John Daly who discussed this, but, if memory serves me well, he did not document the values he presented in his post.

    Yup, just found his discussion:
    http://www.john-daly.com/deepsea.htm

    This discussion starts at heading Do The Oceans Warm The Planet?

    Regards

  21. What has happened to the font? Everything on my machine is now in italics. This usually (for me ) denote emphasis…

    • Yeah, ’tis a bit strange.

    • Word press has a problem when posters don’t close the Italics at the end of their post… This happened back here.>
      izen | November 15, 2010 at 2:15 am | Reply

      The obvious difference between the FAR and the present is the comment –
      “Global – mean surface air temperature has increased by 0.3°C to 0.6°C over the last 100 years, with the five global-average warmest years being in the 1980s. “
      In the two decades since then the 90s were warmer than the 80s and the last decade warmer than than the 90s, the warming has continued, and attribution to CO2 has become much more certain.

      • Richard S Courtney

        Richard Holle :

        You assert:

        “The obvious difference between the FAR and the present is the comment –“Global – mean surface air temperature has increased by 0.3°C to 0.6°C over the last 100 years, with the five global-average warmest years being in the 1980s. “

        In the two decades since then the 90s were warmer than the 80s and the last decade warmer than than the 90s, the warming has continued, and attribution to CO2 has become much more certain.”

        Sorry, but that is a clear misunderstanding (misrepresentation?) of the data.

        The warming occurred in two distinct periods; i.e.
        1910 to 1940
        and
        and 1970 to 2000.

        There is no dispute (even Phil Jones agrees) that
        (a) the warming had the same rate in these two periods
        and
        (b) there has been no statiscally significant warming (at 95% confidence)for the last 15 years.

        But atmospheric CO2 has continued its relentless increase over the last 15 years.

        If the cause of the rise were to be confidently attributed to the CO2 increase then there should be a clear correlation between them. No such clear correlation exists: the most that can be said is that both the mean global temperature and the atmospheric CO2 concentration have both increased over the past century.

        Correlation does not prove causation but lack of correlation indicates lack of causation.

        Richard

      • there has been no statiscally significant warming (at 95% confidence)for the last 15 years.

        Oh come on! This is a bogus argument and you know it is a bogus argument and you know exactly why.

      • Richard S Courtney

        Andrew Adams:

        Are you really trying to say that warming over the last decade at the rate had the same rate as in the periods 1910 to 1940 and 1970 to 2000?

        GISS and HadCRUT3 agree that the rate of warming since 2000 has been much less than in the prevcious 3 decades. Indeed, the recent warming rate is so small that it is not distinguishble from zero at 95% confidence.

        Perhaps you could enlighten me as to why AGW-supporter always dismiss as “bogus argument” any demonstrable facts which they consider to be inconvenient truths?

        Richard

        .

      • Richard,

        No, I am not claiming that warming over the last decade has been at the same rate as in previous decades. We might argue about what that signifies but it is not a “bogus” argument.
        I am objecting to your misuse of the “no statistically significant warming” argument. That is a bogus argument because you are pretending that it means something other than it actually does – you are conflating “warming which is not statistically significant” with “no warming”.
        There has been warming since 1995, it is shown in all of the various temperature records, but 15 years is not (quite) sufficient to establish a statistically significant trend.
        But in any given year you will always need n years of past data to establish a statistically significant trend, so you will always be able to say “there have been no statistically significant warming for n-1 years”. It’s just cherry-picking.

      • Richard S Courtney

        Andrew Adams:

        Please dispute what I say but do not dispute what you assert I have said. You say of me:

        “you are conflating “warming which is not statistically significant” with “no warming”.”

        Say what!?
        When and where did I do that?

        Indeed, I specifically refuted it in the post you are replying when I wrote:

        ” GISS and HadCRUT3 agree that the rate of warming since 2000 has been much less than in the previous 3 decades. Indeed, the recent warming rate is so small that it is not distinguishable from zero at 95% confidence.”

        I can only repeat my question and to and another.

        Perhaps you could enlighten me as to why AGW-supporters always dismiss as “bogus argument” any demonstrable facts which they consider to be inconvenient truths?

        An why do they pretend those inconvenient truths have not been stated but something else has?

        Richard

  22. Richard S Courtney

    Bart Verheggen:

    Your response to “Chip” implicitly assumes the Berne Model is correct. But that assumption is extremely uncertain. Indeed, the 2001 IPCC Third Assessment Report (TAR) states that it has no empirical validation; i.e. Chapter 2 from Working Group 3 in the TAR says; “no systematic analysis has published on the relationship between mitigation and baseline scenarios”. And that situation has still not changed.

    The isotope data adds confusion because if the Berne Model is accepted then the magnitudes of the observed isotope ratio changes differ by a factor of 3 from the “accumulation” of anthropogenic CO2 predicted by the Berne Model. The directions of the changes is correct but their magnitudes are not, and this must – at very least – provide doubt to the Berne Model.

    This matter is important because the AGW hypothesis is founded on three assumptions: viz

    (1) It is assumed that the anthropogenic CO2 emission is the major cause of the increasing atmospheric CO2 concentration
    and
    (2) It is assumed that the increasing atmospheric CO2 concentration is significantly increasing radiative forcing
    and
    (3) It is assumed that the increasing radiative forcing will significantly increase mean global temperature.

    There are reasons to doubt each of these assumptions. But if any one of them were known to be false then the entire AGW hypothesis would be known to be false, so it is important to question each of them with a view to its validation or rejection.

    Unquestioning acceptance of the Berne Model is a failure to question Assumption (1).

    One of our 1995 papers did question the Assumption (1) and concluded that there is very good reason to doubt it.
    (ref. Rorsch A, Courtney RS & Thoenes D, ‘The Interaction of Climate Change and the Carbon Dioxide Cycle’ E&E v16no2 (2005) ).

    That paper assessed mechanisms in the carbon cycle and used model studies to determine if natural (i.e. non-anthropogenic) factors may be significant contributors to the observed rise to the atmospheric CO2 concentration. These considerations indicate that any one of three natural mechanisms in the carbon cycle alone could be used to account for the observed rise. The study provides six such models with three of them assuming a significant anthropogenic contribution to the cause and the other three assuming no significant anthropogenic contribution to the cause. Each of the models matches the available empirical data without use of any ‘fiddle-factor’ such as the ‘5-year smoothing’ the UN Intergovernmental Panel on Climate Change (IPCC) uses to get its model to agree with the empirical data.

    In other words, we conducted attribution studies that used three different models to emulate the causes of the rise of CO2 concentration in the atmosphere in the twentieth century. And these numerical exercises are a caution to estimates of future changes to the atmospheric CO2 concentration. The three models used in these exercises each emulate different physical processes and each agrees with the observed recent rise of atmospheric CO2 concentration.

    The three models were then each used to assess whether the recent rise in atmospheric CO2 concentration could be solely a consequence of the anthropogenic emission or may be solely a result of, for example, desorption from the oceans induced by the temperature rise that preceded it; i.e. a total of 6 models.

    These models demonstrate that the observed recent rise of atmospheric CO2 concentration may be solely a consequence of the anthropogenic emission or may be solely a result of, for example, desorption from the oceans induced by the temperature rise that preceded it. Furthermore, extrapolation using these models gives very different predictions of future atmospheric CO2 concentration whatever the cause of the recent rise in atmospheric CO2 concentration.

    And it is important to note that each of the models in our paper matches the available empirical data (i.e. atmospheric CO2 concentration as measured at Mauna Loa since 1958) without use of any ‘fiddle-factor’ such as the ‘5-year smoothing’ the UN Intergovernmental Panel on Climate Change (IPCC) uses to get its model (i.e. the Berne Model) to agree with the empirical data.

    So, if one of the six models of our paper is adopted then there is a 5:1 probability that the choice is wrong. And other models are probably also possible. And the six models each give a different indication of future atmospheric CO2 concentration for the same future anthropogenic emission of carbon dioxide.

    Data that fits all the possible causes is not evidence for the true cause. Data that only fits the true cause would be evidence of the true cause. But the above findings demonstrate that there is no data that only fits either an anthropogenic or a natural cause of the recent rise in atmospheric CO2 concentration. Hence, the only factual statements that can be made on the true cause of the recent rise in atmospheric CO2 concentration are

    (a) the recent rise in atmospheric CO2 concentration may have an anthropogenic cause, or a natural cause, or some combination of anthropogenic and natural causes,

    but

    (b) there is no evidence that the recent rise in atmospheric CO2 concentration has a mostly anthropogenic cause or a mostly natural cause.

    This finding is consistent with the statement in IPCC TAR that says; “no systematic analysis has published on the relationship between mitigation and baseline scenarios”.

    Richard

    • Richard S Courtney

      Oops! Of course I meant to tye “One of our 2005 papers …”.
      Sorry.

      Richard

    • AnthropoceneEndGame

      “There is no evidence that the recent rise in atmospheric CO2 concentration has a mostly anthropogenic causes or a mostly natural cause”
      Either a lie, or you’re ignorant of the science– you pick.

      Start with this primer:

      esrl.noaa.gov/gmd/outreach/isotopes/

      • Richard S Courtney

        AnthropoceneEndGame:

        Your loutish stalking of me on this blog is becoming tedious. Indeed, I wonder why it has not yet been moderated. So, I shall ignore it and make no responses to it after this.

        But for now, your apparently complete ignorance of the carbon cycle may be aleviated by reading (as a primer) our paper that I referenced in the post to which you have appended your silly comment.

        Richard

      • Actually AEG was correct, and he left you with two good options for picking…

      • Richard S Courtney

        Chris Colose:

        You say;
        “Actually AEG was correct, and he left you with two good options for picking…”

        Right about what? It would be a first on this blog.

        If you have a substantive point (critical or affirmative) to make, then please do, but merely saying you support the stalker is pointless.

        Richard

      • AnthropoceneEndGame

        “Right about what?”
        Right about the science of distinguishing the isotopic ‘fingerprints’ of man-made atmospheric carbon from naturally occurring carbon.
        See the NOAA link I provided, stop the pretense, and learn something.

        CC presumably supports the science provided by the ‘stalker’ (!) which you are unwilling to read.

      • Richard S Courtney

        AnthropoceneEndGame:

        Your comment is silly and abusive. Of course I have read that link and much else beside. You clearly know nothing about the carbon cycle and your merely posting links to web articles does not disguise that fact.

        However, if web articles are the only source of information that you like then try this one from Roy Spencer
        http://wattsupwiththat.com/2008/01/28/spencer-pt2-more-co2-peculiarities-the-c13c12-isotope-ratio/
        This link differs from yours in that it also includes comments (both supportive and critical) of Spencer’s analysis.

        The link I provide demonstrates the range of problems in assessing the isotope data. Indeed, Spencer’s article concludes by saying:
        “BOTTOM LINE: If the C13/C12 relationship during NATURAL inter-annual variability is the same as that found for the trends, how can people claim that the trend signal is MANMADE??”

        But, better than web articles, read some of the papers I have co-authored on the subject and perhaps you will start to learn something about the carbon cycle.

        Importantly, if you have any point of dispute with any of our analyses then I would like to hear it. But your abuse indicates that you cannot dispute any part of them. I would regard such failure to find fault in my work as being a complement from someone whom I respect.

        Your stalking of me on this web site to throw abuse tells much about you and nothing about my work. And, no, your behaviour is not going to drive me away. You demonstrate your cowardice by conducting your stalking from behind a screen of anonymity provided by an alias, but I do not share your affliction.

        Richard

      • AnthropoceneEndGame

        Thanks for the citation, the one where Spencer hung himself out to dry (he’s nevber done that), corrected his errors in the exchange, and never got his ‘ideas’ published? If there’s anyone who doesn’t know the carbon cycle it’s Roy. And if there’s anything I ‘stalk’ it’s fringe garbage, posing as science, your favorite. What’s up with that?
        Try again, King Coal.

      • Richard S Courtney

        AnthropoceneEndGame:

        Thank you for your confirmation that you can find no flaw in our work.

        Richard

      • AnthropoceneEndGame

        E&E is trade journal for people like you. That’s why you’re on their Board. It’s garbage, and no one in the field reads it.

      • Richard S Courtney

        AEG:

        Yours is the first time I have heard academia described as a “trade”.

        And the ‘climategate’ emails state that the self-titled ‘Team’ read it: Trenberth specifically states E&E’s peer review procedures. So, you are claiming they are not in “the field”, which is a claim which is similarly valid as all your other claims on this blog.

        Richard

  23. Harold Pierce Jr

    Chris Close says:
    The first issue, which steve mosher described well, is if we take a CO2 forcing and make everything else equal, the temperature is mandated to rise.

    In the real atmosphere, you can not “make everything else equal, ”
    Watch weather reports on the TV . There is no uniform distribution of
    clouds in space and time as shown by satellite images. Clouds modulate the earth’s various climate zones and regions. The temperature may or may not rise from a CO2 forcing. This depends on cloud response and behavior.

  24. “What happned to the font”.
    Someone left an html italic tag open. Naughty izen.

    Let’s see if I can fix it.

  25. Harold Pierce Jr

    ATTN: Bart
    Why do I have to keep reminding you and the clueless (i.e., ignorant) multitudes that “Fossil Fuels Are Forever”

    Harold the Chemist says:

    Boats, planes, freight trains and trucks, military and emergency vehicles, heavy machinery used agriculture, construction, forestry and mining, cars and light trucks, recreational vehicles, and so forth will always require and use hydrocarbon fuels because these fuels have high energy density and are readily prepared from abundant crude oil, which exists free in Nature, by fractional distillation and blending of the distillate fractions, low energy processes which do not involve the breaking of chemical bonds. Even catalytic cracking of the heavy distillate fractions into lighter fractions for fuel formulation is a relative low energy process.

    FYI: A Boeing 747 takes off with 346,000 US gallons of fuel for a long intl. flight. At large airports big jet are more numerous that house sparrows

    In the heavy industries, only fossil fuels can supply the heat energy and high process temperatures either directy or indirectly (e.g. the electric furnace) required by lime and cement kilns, smelters, steel mills, foundries and metal casting planets, all facilities manufacturing ceramic materials (glass, bricks, tiles, porcelin ware, china , etc), refineries and chemical plants and so forth.

    Diesel-electrical generating systems are used extensively throughout the world for primary and back-up power and for power generation in many delveloping countries and at remote locations (e.g., diamond and gold mines, resort islands, drilling rigs, movie sets, etc). Electrical generators using gasoline are quite portable and are used for small snd modest power requriments.

    Many processes in food production require large amounts of heat for baking, cooking and steam for sterilization, etc which can provided economically by fossil fuels. Drying of grain for storage requires enormous amounts of heat which can only be provided economically by fossils fuels.

    Energy for space heating especially in cold climates and hot water production and for electricity generation, in particular for refrigeration, communication systems, hospitals and emergency services, is provided most reliably and economically by use of fossil fuels. .

    The most wasteful use of energy is diamond mining. Tons of ore are sometimes processed to obtain a few carats of rough diamonds which lose about half of their weight in the cutting and polishing processes. About 80% of gold production goes to the jewerly industry.

    Who among you wants to tell the ladies, “No more diamonds, gold, sliver, platinium, rubies, emeralds, etc for jewerly.” In NYC, they would become outraged, ponce on you, take off the Pradas and pound you into hamburger which they would feed with glee to coyotes in Central Park!

    I don’t want read any more foolish comments about getting rid of fossil fuels. Ain’t ever going to happen.

    • Slight issue: Fossil fuels are finite. So we are going to get rid of them – indeed we are currently getting rid of them at a pretty high rate by dint of extracting them and burning them.

      Ultimately, all fossil fuels can be replaced; they are after all either carbon or carbon compounds, and synthesizing them is merely a matter of having sufficient energy. Although you’d only really bother for liquid fuels in mobile applications, where electricity is inconvenient; even then you’d probably create methanol on the grounds of the chemical synthesis being easiest of all carbon based liquid fuels.

      As an energy source, the easiest solution overall is probably the nuclear breeder fission reactor, based on either Uranium or Thorium fuel cycles. Breeder reactors minimize both high level waste and fuel mining requirements; indeed if the fission products are also used (nuclear batteries being the obvious application) then the goal of fully waste-free energy production could be realized.

      Thorium goes into the nuclear park, electricity and methanol come out. Discussions of global warming and energy shortages go back to the realm of theory.

      • Richard S Courtney

        Andrew Dodds:

        You make the correct statement;
        “Ultimately, all fossil fuels can be replaced; they are after all either carbon or carbon compounds, and synthesizing them is merely a matter of having sufficient energy.”

        Yes, but do you not agree that in the absence of totalitarnianism (which some of us do not like) economics plays a part in whether fossil fuels will be eliminated by replacement with synthetic compounds?

        As I explained on another thread, the effect of economics and fossil fuels having the ability to be synthesised from one fossil fuel to another means that for all practical purposes fossil fuels can be considered to be infinite.

        As you say, fossil fuels can also be synthesised from other things, but so what? Nobody is going to make expensive synthetic fossil fuels while fossil fuels are available and cheaper.

        So, Harold Pierce Jr is being realistic about the foreseeable future when he says;
        “I don’t want read any more foolish comments about getting rid of fossil fuels. Ain’t ever going to happen.”

        Richard

      • Craig Goodrich

        One long-term suggestion has been to use waste heat from nuclear power plants to produce liquid fuel from coal, which is far more abundant (at least in currently known reserves) than oil.

      • AnthropoceneEndGame

        “I don’t want to read any more foolish comments about getting rid of fossil fuels”
        THIS is the totalitarian voice of the energy cartels.

      • Phillip Bratby

        No, it’s the voice of common-sense. As long as there are fossil fuels available, they will be used, because we cannot manage without copious energy (unless we all go back to being peasants).

      • AnthropoceneEndGame

        See today’s NYT:
        “Peak oil is not just here–it’s behind us already”

        Humanity going to have to ‘manage without copious energy’, if you meant crude.

        I can’t wait to hear what the ‘common sense’ energy interests represented here have to say.

      • Let’s go ‘tar sands’ and ‘oil shale’.

        Use nuclear energy and/or wind power and/or geothermal energy and/or solar energy and/or petrochemical byproducts to do the extraction and cracking.

      • There’s a basic error of logic in that statement, though: Why are fossil fuels the only copious energy source that we are allowed to use?

      • Richard S Courtney

        Andrew Dodds:

        As a non sequiter your comment takes some beating.

        I wrote:
        “As you say, fossil fuels can also be synthesised from other things, but so what? Nobody is going to make expensive synthetic fossil fuels while fossil fuels are available and cheaper.”

        Philip Bratby supported that saying;
        “it’s the voice of common-sense. As long as there are fossil fuels available, they will be used, because we cannot manage without copious energy (unless we all go back to being peasants).”

        And you have responded by saying and asking;
        “There’s a basic error of logic in that statement, though: Why are fossil fuels the only copious energy source that we are allowed to use?”

        The only “error of logic” is your assumption that people only use the cheapest thing because that is the “only” thing they are allowed to use. But your assumption is plain wrong.

        People always do the cheapest thing because it is cheapest unless a more expensive option gives them some personal advantage.

        If you think otherwise then try making and selling your synthetic fossil fuels without subsidy and see how long it takes to go out of business.

        Richard

      • No.

        The error of logic was to assume that only fossil fuels could provide sufficient energy to run an advanced industrial economy; and the only alternative to that would be technological regression.

        As far as fossil fuels being cheapest, certainly in the case of coal fired electricity this is only because of a lack of accounting for externalities and the fact that many fixed costs have already been paid. As far as oil goes… how do you account for the economic costs of keeping military forces in the Persian Gulf? Never mind the implicit funding for extremists. I think the world is a bit more complicated than you think.

      • As far as economics goes, of course, I’d have to point out that Coal gets a free pass in many areas – mine clear-up, mercury and uranium emissions, particulates (in many places), and carbon dioxide. I suspect that the economics would work out rather differently were all power sources required to pay for all of their externalities.

        (This would, of course, also apply to wind and solar having to pay for the cost of storage or backup)

        I certainly do not agree that reserves are ‘practically infinite’; we have already hit capacity limits for oil, natural gas is now onto expensive non-conventional supplies and if you want to expand coal to the point of supplying the whole world at 1st world energy consumption levels, AND substituting for oil and gas, then you’ll find that you hit shortages quicker than you think.

        Never mind that burning that amount of fossil fuel – if it were technically possible – could lead to a quadrupling of atmospheric CO2 from pre industrial, and even the lowest creditable estimates for CO2-sensitivity would put us in danger at those levels.

        As far as talking about totalitarianism goes, having an energy policy for a country is not oppressive; energy, with it’s large fixed investments, extremely long investment horizons and relative paucity of realistic options, is a good candidate for a process where techncial experts may make better decisions than market forces.

      • Richard S Courtney

        Andrew Dodds:

        Sorry, but you are wrong about the economics. Each of your assertions is rehetorical and not factual. Indeed, the world probably is “more complicated” than I think and it is certainly much, much more complicated than you assert.

        It would take too long to dismiss all your mistaken assertions about “externalities”, so I will choose one that is simply dismissed.

        You ask:
        “how do you account for the economic costs of keeping military forces in the Persian Gulf? ”

        I answer as follows.

        This is a political decision based on need for national security including avoidance of wars and invasions. This need certainly does include protection of oil supplies from the Middle East, but that is only one small part of the political equation.

        Consider the US military involvement in the Middle East. It is less than in Europe where (excluding the UK and Norway) there is little oil production. True, the military activity in the Middle East increases on occassions (e.g. the Gulf Wars) but it has also done that on occassions in Europe (e.g. in the years prior to 1919 and 1946).

        Protection of oil supplies is only one – and a minor one – of the reasons for US military involvement in the Middle East. Indeed, the US obtains most of its oil imports from Canada and could completely displace its oil imports from the Middle East if it were to produce more oil from Alaska and from its off-shore resources.

        Clearly, Big Oil is not the primary reason for US military involvement in the Middle East and, therefore, asigning the costs of that military involvement as an “externality” of fossil fuels is plain wrong.

        Your other assertions are plain wrong, too. I am sure you could convince the trolls on this blog of your assertions, but try convincing politicians who need to decide these matters and you will get laughed out of the room.

        Richard

      • A very strange post indeed.

        The only point you bothered to answer was about US military involvement in the middle east. The fact that this is less than, for instance, Europe is neither here nor there; plus, of course, you seem to forget basic market economics regarding oil; an interruption to ME supplies would cause shortages for all oil-importing countries (and quite possible some exporters) due to the fungible nature of crude oil. It goes to the highest bidder.

        Given that you managed to get that wrong, I doubt you’d do much better on questions of a more technical nature.

      • Richard S Courtney

        Andrew Dodds:

        Your content- free set of ad hom tells more about your lack of knowledge of the “economics” than my own. But, since you are interested in that, I copy from another thread of this blog something I posted about ‘peak oil’ because it seems to be pertinent. I wrote:

        Benjamin:

        It seems that you do not understand these issues. Concerning the very adequate reserves of oil, you say:

        “It’s meaningless.

        What matters is production rate.

        Adding reserves accessible by just digging a hole in the sand in Saudi Arabia and reserves offshore Brazil under 5.000 meters of water, 2.000 meters of salt and 2.000 meters of rock is meaningless.

        Why not adding the oil reserves found on Titan too ?”

        Yes, production rate matters, but that is an economic judgement. And your facile comment about Titan is just plain silly: nobody can get anything from there so whatever is there cannot be a resource.

        The issue is reserves and resources, and both of these are determined by economics.

        If there is insufficient supply then the price will rise until balance is re-established between supply and demand (this is economics 101).

        The balance is achieved by two effects.
        1. When the price rises then producers have an incentive to increase production (and vice versa).
        and
        2. When the price rises then purchasers have a disincentive to buy (and vice versa).

        So, the limiting factors are
        (a) the need for oil by its purchasers (i.e the maximum they can or will pay for it),
        (b) the resources available to oil producers,
        and
        (c) the costs of production the oil producers have.

        These factors determine the reserves (i.e. the amount that can be produced at economic cost).

        But the profits available to producers vary with both output (that has production cost) and price. Producers provide a production rate that maximises their profits.

        If the supply gets too great then the saleable price falls so producers reduce output with resulting return to higher price.

        And if the supply gets too low then the saleable price rises so producers increase output with resulting return to higher profits.

        Therefore, the available oil from “digging a hole in the sand in Saudi Arabia and reserves offshore Brazil under 5.000 meters of water, 2.000 meters of salt and 2.000 meters of rock ” is NOT “meaningless”: such possibilities are crucial ecause they enable additional production with additional production rates (albeit at higher production cost). Simply, the availability of any source affects both the available rate of production and the cost of production.

        The most important factor affecting production is price because at low price the sources with highest production costs are not economic.

        Importantly, these factors are complicated by
        (i) the oil companies making most profit from trading and not production
        and
        (ii) short-term market fluctuations.

        But that does not alter the fact that the oil companies have little difficulty in adjusting output as they wish (unless governments prevent them) so long as adequate resources exist. Indeed, this is why OPEC was founded. At that time there were insufficient producer countries around the world for market forces to operate and, therefore, producer countries were concerned that a single producer country could ‘game’ the system. But OPEC has since lost its power to control production rates as more countries have become oil exporters so market forces have taken over OPEC’s power.

        Simply, oil is a fungible commodity. Reserves and resources are what matter and market forces determine production rates.

        Richard

  26. Willis,
    This planet has given us ample evidence that actual physical changes to the atmosphere are occuring.
    Scientist are so hyper focused on temperatures and models, they failed to see the actual problem.
    Do greenhouses build up pressure?
    Of course not, so their models fail to include an enclosed biosphere.

  27. Harold Pierce Jr

    God Morning Judy!

    You should definetely check out Alan Cheetam’s website “Global Warming Science” at:
    http://www.appinsys.com/globalwarming/

    This website has the most comprehensive info and data on global warming and climate change on the planet, and is orders of magnitude better than any website I visited so far.

    BTW, did you check out the late John Daly’s website “Still Waiting for Greenhouse”?

  28. Judith,

    I have come accross so much science that does not include the rotational energy our planet has infused to the molecules rotating with us. So, actual physical energy is not taken into account as the theories have already been established and made into LAW.

  29. Joe

    Sorry to rain on your parade again, but they don’t take into account the enormous energies available via nuclear fission either. And the reason is that they, too, are potential energies only. Until you can come up with a way of turning that potential energy into another form, then your observations remain interesting but irrelevant.

    I remember thinking about this question when I was a kiddiewink. Because it seemed to me that if an aeroplane took off and just waited in the air until the earth had rotated far enough round beneath it and then landed, it would not need to use any fuel. And it could go right round the Earth in about 24 hours. It took me quite a while – and a bit of help from my Grandad who was a scientist – to figure out why this was not used as a cheap and quick means of transportation.

    If the answer isn’t obvious, have a think about the speeds of the aeroplane when it takes off..relative to the ground, relative to the air and relative to some ‘fixed position’ in space. Come back in a while if you’re still having problems and I’ll try to help. Good luck….LA

    • But they are relevent to understanding where tornadoes and hurricanes get their ACTUAL physical energy. I have yet to see a tornado form on the ground. Windswirls yes but not the massive energy held to produce wind.
      Suns energy can only be absorbed or deflected but current science believes this is where wind comes from…does that make sense?
      Current planetary windspeeds are dying down why?
      They are all inter-related. It means more density of molecules building -up in the atmosphere.
      What happens to the windsheer that breaks up cloudcover created by evaporation?

  30. Willis Eschenbach

    Trying to clear italics

  31. Dr Michael Cejnar

    This discussion is great, but seems to be an echo of AR4 and does not answer the many question raised by skeptics and recent findings:

    1. Are you saying – CO2 with positive feedback makes my models work so they must be right? Chris Colose – you say “The working definition of net positive feedbacks in climatology is simply that the final temperature response is greater than the no-feedback Planck radiative response alone, which is about a quarter degree C per (W/m2) forcing, with very little uncertainty.” If so, is this not just a hypothesis awaiting validation – and nothing more. Any number of the postulated natural phenomena, even the mutidecadal ones could make the model work, if included.

    2. What is the physical evidence for this positive feedback – the only direct study found a negative of flat response (Linsen & Choy 2009 – even with some error corrected). If there is strong evidence of +ve feedback – why is it not on the news?

    3. Catastrophic model preditions rely on CO2 e-folding or settling time being 50 to a 100 years in IPCC and up to 1000 year (residual) in others. The only evidence IPCC gives is a Footnote a: “The CO2 response function used in this report is based on the revised version of the Bern Carbon cycle model used in Chapter 10 of this report” – so the Bern Model assumptions feed into the Climate model assumptions. In engineering, these uncertainties would have to be multiplied. Is there not one physical study?

    4. I would also like an honest explanation of the hard to find tropospheric hotspot. The evidence for it after 20 years seems unconvincing to me – arguments of windsheer proxies, too large error bars (ironically – one of the few times I recall climate scientists showing error bars on graphs) or attempts to make its absence irrelevant because it’s non-specific to water vapour fedback all seem disingenuous.

    5. 15 years of flat temperature or cooling I think deserves a mention and explanation how that fits in with CO2 being the dominant regulator of climate and when will this make climate models fall outside their 95% confidence – or more importantly – if IPCC was >90% sure when models were spot on temperature, how is that confidence now?

    6. Finally, in all the explanations by experts above, including Dr Curry, why is there no discourse on clouds, apart from a mention by Chris Colose, and then largely in a context of Venus? Not mentioned either are effect of cosmic rays, solar cycles, atmospheric convection, and multi-decadal ocean currents as alternative or contributing explanations supplanting the need for +ve feedback. I have read that they explain >50% of modern warming – should this not reduce the need for +ve feedback in the models – I would be interested in Dr Curry’s analysis of these.

    • Aaaaargh – this is doing my head in! I’ve come to this site hoping for enlightenment and all that happens is that I get more and more confused as I bounce between commentators. Just as I thought my skepticism was on the wane, this excellent comment came along and I’m back where I started. Maybe the subject is just too big to be able to form a definitive opinion, but it’s certainly addictive. :)

      • Hi Rob– addictive indeed!!

        If I may make a suggestion, if you truly have a passionate interest in sorting through the technical arguments in the blogs, I would suggest starting off with some textbook material on climate. Some standard references are Hartmann’s ‘Global Physical Climatology,’ Houghton’s ‘Physics of Atmospheres’ if you have some calculus and physics behind you, and Ray Pierrehumbert has an up and coming book. The best text I know of that treats the subject in some detail but doesn’t require advanced mathematics is David Archer’s Understanding the Forecast, which only requires a bit of basic algebra to sift through. Once you become acquainted with the basics, maybe look at some peer-reviewed papers, a good start would be reports or review papers (like NAS reports, IPCC, etc).

        I think an issue on the blog debates, much like the evolution-creation wars, is that so many people attempt to step into the blogs without this basic grounding in climate science, and therefore are prone to making decisions based on “their favorite choice” or by following whoever appears to be the most articulate.

      • Chris describes the fundamental problem very well. If this is required reading before anyone is qualified to discuss the theory, concept and policy implications of AGW then the cause is already lost. The average voter or congressman will never go there.

        Another way to approach this is for AGW advocates to appreciate that we all come from different backgrounds and yet are people of equal value at the voting booth. Speaking in terms that listeners can understand. Speaking to them as people of equal value. Save the lectures for the classroom. Acknowledge uncertainties within climate science.

        One of my favorite examples of scientists talking over listeners heads was the weeks long, highly detailed scientific analysis of DNA evidence at the OJ trial. The scientific evidence was irrefutable. His blood was all over the crime scene. And yet OJ was found not guilty. A paraphrased quote from one of the jurists after the trial: “I don’t know nothing about no DNA”

        What we have here is a failure to communicate. If AGW is real (and I believe it is but to a lesser degree than many) there should be a way to tell people about it without making them feel stupid or irrelevant.

      • @ivpo

        Your point is exactly spot on!

        I do not foresee much positive endorsement from Joe Sixpack when he quite reasonably asks why he cannot any longer take his family for a sunshine holiday as the aeroplane taxes are so high. Or that he must pay extra in his energy bills because they are shutting down all the tested and reliable coal and nuclear station son favour of ten times more expensive – and totally unreliable – wind power.

        And I explain to him that unless he

        ‘understands the issues of band saturation, spectral selective absorption, etc then he just isn’t in a place to make authoritative judgments on the quality of climate science’. And that he should just do what he’s told by his intellectual superiors.Because his just a stupid peasant. Then I expect that Joe might be less than convinced. And possibly even annoyed enough to vote against such propositions next time.

        Some climate scientists may be quite ‘bright’ in the passing exams sort of a way. But as a collective they have almost no interpersonal skills. Read the Denizens blog and see how many well-qualified and experienced people with real practical experience of related fields have been disgusted by the arrogance and sheer unpleasantness of the ‘community’. As well as the ‘misbehaviour’ (I am being charitable) so graphically revealed in Climategate.

        I’m with Ivpo above, but would go further. If you can’t make your ‘science’ irrefutably clear to the interested man in the street, and answer his simple (sometimes deceptively so) questions with good grace and an open manner, then you deserve to fail in your cause. Judging by this blog, you guys still have a very long way to go.

      • Latimer, please see below.

      • “I’m with Ivpo above, but would go further. If you can’t make your ‘science’ irrefutably clear to the interested man in the street, and answer his simple (sometimes deceptively so) questions with good grace and an open manner, then you deserve to fail in your cause. Judging by this blog, you guys still have a very long way to go. …”

        The “deserve to fail” thing is just plain weird as far as I’m concerned.

        IMO, they’ve made the science quite clear and understandable. They cannot make it what it isn’t: easy.

        I would disagree a bit with CC on reading peer-reviewed papers. I have no science background at all and no math background, but I think I can achieve a fairly good understanding of things from reading peer-reviewed papers. It was not easy at first, but I work hard. Sometimes I have to read things several times, and do a lot of digging from other sources to slice away at my confusion, but I get a great deal out of them. I agree with him that somebody with upper-level math can garner far more and spend a lot less time.

        CC has probably taken time to answer some of my silly questions as he commonly answers comments on climate blogs, and he’s written very helpful things for people at my level to read, and he’s given excellent tips on how to improve understanding.

      • AnthropoceneEndGame

        RobB:
        I would highly recommend that you take the comments in this discussion with a grain of salt unless citations are provided to back-up claims.
        In other words stick with the science, like this from NASA:

        ‘CO2: The Thermostat that Controls Earth’s Temperature’ by A. Lacis (Oct 2010)

      • AEG,
        Please go read Dr. Roy Spencer’s response (at his website) to that article. He does not agree with that paper.

      • Also, read the response to Christy by Lacis in the comments.

      • AnthropoceneEndGame

        And then read where Spencer agrees with the findings of the Lacis paper….but who cares? Why do deniers turn to Spencer like he’s the only standing authority on climate science? Is any one else sick of him comlpaining that he couldn’t get a critique published if he tried? Heck, why not create a ….blog.
        What a joke.

    • Richard S Courtney

      Dr Michael Cejnar:

      You ask:

      “Catastrophic model preditions rely on CO2 e-folding or settling time being 50 to a 100 years in IPCC and up to 1000 year (residual) in others. The only evidence IPCC gives is a Footnote a: “The CO2 response function used in this report is based on the revised version of the Bern Carbon cycle model used in Chapter 10 of this report” – so the Bern Model assumptions feed into the Climate model assumptions. In engineering, these uncertainties would have to be multiplied. Is there not one physical study?”

      I discussed this issue in my paper
      (ref. Courtney RS, Crystal balls, virtual realities and ‘storylines’, E&E (2001) )
      which provided a critique of the SRES analyses in Chapter 2 of Working Group III in the IPCC’s Third Assessment Report (TAR). In that paper I explain:

      “Also, the scenario authors do not place any probability levels on their scenarios. This means that they – and everybody else – are forced to assume that even the most improbable – some say ridiculous – scenarios are just as likely as those that agree with reality.

      Additionally, the word “scenario” may be thought to be ambiguous. The problem arises because the scenario authors use a method that does not permit distinct separation of scenario types. The method has the following stages.

      a) “Storylines” of future human activity changing over time are created (i.e. social/technology change scenarios).
      b) For each “storyline”, the GHG emissions anticipated in future years are estimated (i.e. emissions modelling).
      c) The changes to mean global temperature in future years resulting from the anticipated future GHG emissions are estimated (i.e. climate modelling).

      The complete scenario contains all three stages; (a), (b) and (c). Hence, in each complete scenario, accumulating effects resulting from social/technology changes alter extrapolations from existing social/technology systems, existing GHG emissions, and existing climate.”

      Etc.

      Richard

  32. Judith,

    Twenty yeas ago, NASA’s articles were also accurate in the following summary:

    … For example, in the early 1970’s, because temperatures had been decreasing for about 25 to 30 years, people began predicting the approach of an ice age! For the last 15 to 20 years, we have been seeing a fairly steady rise in temperatures, giving some assurance that we are now in a global warming phase.

    NASA FACTS – Global Warming – April 1998, NF-222
    http://bit.ly/9qpdUD

    Here is the data that supports the above statement:
    http://bit.ly/96nokt

  33. The FAR Summary for Policy Makers makes the following statements:

    We are certain of the following:

    ■there is a natural greenhouse effect which already keeps the Earth wanner than it would otherwise be

    —————–

    Let’s leave aside the question of whether the IPCC’s assessment is correct; that is that it is not biased and selective primarily of literature that supports the thesis of AGW-by-CO2.

    Then what to make of the TAR statement, “there is a natural greenhouse effect which already keeps the Earth wanner than it would otherwise be”?

    Wouldn’t a clearer statement be something like (my words), “If we take the existing Total Earth System and, by thought experiments, add or subtract various atmospheric gases (without varying anything else) then we have the possibilities of both the reduction and/or increase of Total Earth System energy levels on cycles of varying timescales. Any given atmospheric thought experiment can lead to new cycles of both reduction and increases in Total Earth Energy levels. We do not know yet what the real Total Earth System does in any of these thought experiments, although some knowledge of the earth in the past many millions of years gives reasonable evidence that higher temps (by whatever cause) is not a catastrophic issue and likewise higher CO2. ”

    BTW: The word ‘greenhouse’ is very unscientific and is misleading.

    John

    • Note: I think that the italic html tags and may not be functioning properly.

    • AnthropoceneEndGame

      So for you higher temps in the geologic past ‘is not a catastrophic issue’.
      How convenient, and completely wrong. See ‘Anoxic Events’ at wiki for a primer.

      • AnthropoceneEndGame,

        Thanks for the comment.

        To me it looks like the only mass extinction event that does not appear to have been identified with a probable massive volcanic or large meteoric causation was the late Triassic extinction event that was about 201 mya. The CO2 level estimates just prior to and during the 201 mya extinct event were much less than the average CO2 level estimates for the whole Mesozoic Era (251 to 65.5 mya). The Mesozoic Era was perhaps the richest time of abundant life on earth. Note: Also, the temp anomaly estimates just prior to and during the 201 mya extinct event were much less than the average temp anomaly estimates for the whole Mesozoic Era (251 to 65.5 mya). So, GW and Anoxic Ocean by atmospheric CO2 does not make much sense as a cause for the 201 mya extinction event.

        John

      • AnthropoceneEndGame

        “So, GW and Anoxic Ocean by atmospheric CO2 does not make much sense as a cause for the 201 mya extinction event”.

        How about for the PETM (Paleocene-Eocene Thermal Event) ?
        For a good intro for the layperson, see P. Ward’s book UNDER A GREEN SKY. Then fast forward to the Anthropocene…End Game.
        I don’t think the average chick or dude on the street really understands how rapidly, in an eyeblink of geologic time, our species is adding carbon to the atmosphere. I think if folks can get that concept into their heads (versus what the ‘mind sucking devices’ entertain their brain with), we’d have little argument about the dangers of a planet with atmospheric carbon at 600 ppm. Sadly, unemployment, bad science educations, mind suckling devices, and the energy cartels are tipping this ‘debate’, at least in this country.

  34. Just start your next comment with an end-italics tag. (That’s open angle-bracket, upstroke, i, close angle-bracket).

  35. |
    Chris Colose wrote
    quote
    The question naturally arises to what extent are forcings expected to change in the future. On the anthropogenic side, this is clearly a socio-economic issue, but to the extent that air pollution doesn’t increase dramatically it seems reasonable to suggest aerosol effects won’t change significantly, or even decline in importance, as is reflected in surface brightening trends over much of the globe (with the exception of China, possibly some other territories like India but I’d have to look this up).
    unquote

    Are you happy with our knowledge of aerosols – both future predictions and past and present trends? Has it improved, ie smaller uncertainties, as the reports have been refined?

    If not, of course, then reasonable assumtions are rendered impossible.

    JF

  36. Ref – “The FAR Summary for Policy Makers makes the following statements: (etc)…”

    Perhaps it would be easier to rank the pieces of the FAR Summary for significance as individual points and assign a level of confidence rating? As written, the statements have a scientific-political tone and inferrence. Need to trash the political.

    As “Points of General Agreement” there doesn’t appear to be much hope as it’s currently writen.

  37. Beeause Chris Colose in his various comments has done such a remarkable job describing our current understanding of climate change, I don’t see how I could add much in the way of content. My only criticism of his commentary is that some of his points will seem a bit cryptic to readers without a background in geophysics/climatology and a familiarity with the current literature.

    My larger concern with this post and thread, however, relates to the definition of “we” in the title. If “we” refers to members of the scientific community actively engaged in work on the areas cited in the FAR, confidence in the conclusions has certainly risen since the time of that report. Uncertainties remain, of course, but the general conclusion that we are warming the planet, primarily via CO2 and other greenhouse gas emissions, and with potentially serious adverse consequences, has been greatly strengthened by the accumulation of evidence. “Confidence”, however, remains in the mind of the beholder, and many of the comments here and elsewhere in the blogospher clearly signify a lack of confidence in the conclusions drawn by mainstream science.

    I don’t know how to remedy this level of discordance, which is reinforced by the substantial economic and political implifcations that follow from the scientific conclusions. Further discussions here, as Judy Curry has envisioned, may be helpful, but I remain pessismistic that much agreement will be reached in the immediate future. In my view, we will have to wait for an unassailable authority to tell us who is right. I expect we’ll hear from that authority sooner or later. Its name is Nature.

    • Beeause Chris Colose in his various comments has done such a remarkable job describing our current understanding of climate change, I don’t see how I could add much in the way of content.

      Agreed.

      ‘Rationality’ is a wonderful thing. All else is meaningless and irrelevant.

      I shut up and go away now.

  38. Dr C
    Currently, Realclimate has a post by Gavin where he writes:

    ” I have criticised Judy Curry for not knowing enough about what she has chosen to talk about, for not thinking clearly…”

    In the ‘not thinking clearly’ part, he links to a blog comment he gave addressing you, at Collide-a-scape. In that thread – titled ‘The Curry Agonistes’ – you laid out your objections clearly, spread out over several posts, for why the IPCC derivations about the 20th century warming were not all that confidence-inspiring.

    We now know that Gavin, James Annan and others, have used that episode and others to claim, that you have not confronted their counterpoints to your objections about the IPCC.

    I have not seen them confront the line of thinking that you laid out sincerely either. What I do see are several ad hominem comments and blog posts. But no matter, they stick to their line.

    For example, we can catch this from Gavin downstream in the same thread:

    “No-one has claimed that there is zero contribution to the 50 years trends of multi-decadal internal variability (of all types – not just that associated with the modes you name) – but note that the contribution may have been positive or negative, just as no-one is claiming that there is no forced component 1910-1940. It is also clear that trends over 10 years have a higher internal component than trends over 50 years, so I don’t understand your jab at Hansen and Rahmsdorf at all.”

    In my understanding, this statement supports tacitly, though perhaps inadvertently, that what you formulated about the 1910-1940, 1940-1970 periods is basically correct, which implies that the IPCC is over-reaching, but yet the argument veered away with Arthur Smith and other loudly protesting about aspects peripheral to the central line of discussion in those few posts – and the central focus was subsequently lost.

    You did write however that you will turn to the ‘technical issues’ at some point when you have the time.

    Since we are now talking about “what do we know with confidence”, would it be possible for you, to sketch out what you said earlier, in a single post with references etc – so that people can have a go at it?

    Thanks

    • Regarding the detection and attribution thing discussed at c-a-s (hardly the place to make detailed technical argument), i did a multi-part series at climate etc., on overconfidence in IPCC’ detection and attribution. They (Tobis, Annan, etc) then tried to twist the IF analysis into curry is an idiot, when the IF application in that post was intended as a simple heuristic device to think about the the uncertainties in aspects of the IPCC and to raise issues of ambiguities in the ipcc’s confidence statements. I have been meaning to write an extensive post on the IF for several weeks, but i got waylaid by heretic, climategate, and now testimony (in addition to this being an accutely busy time both for my day job and my weekend job). IF is at the top of my list in terms of substantive post as soon as i have time (hopefully before thanksgiving.) At this point I have no time to read stuff at RC or anywhere else for that matter. I frankly have better and more important things to do than deal with the little tempests created elsewhere in the climate blogosphere, but I have multiple reasons for wanting to do a more extensive IF post.

      And if people want to argue this with me, they should come over here to do so (Tobis scores points in this regard).

  39. It should be obvious by now that we don’t agree on much. That tells me we need a better clarification of the “we” who do.

  40. From dp

    ‘It should be obvious by now that we don’t agree on much. That tells me we need a better clarification of the “we” who do’.

    But how can this be? Surely we all agree. There is a consensus n’est-ce pas? And most here seem to have thoughtful and well-considered points – on both sides of the argument.

    I don’t pretend to judge the rights and wrongs of all of it, but I do observe that nobody here has mentioned: Creationism/Evolution, One World Government or their paycheques from Big Oil or Koch Industries.

    Nor has anybody been going around ‘denying’ anything. This has not been a slug fest of evil deniers despoiling the planet against the forces of truth, justice and Mother Gaia. Which in many ways is quite refreshing, and Judith deserves enormous thanks for bringing about the circumstances that have allowed such a debate to occur.

    But the big conclusion I draw is that even among the scientifically literate there is very little ‘consensus’. There are huge differences of opinion even about the basic science. Those who say that it is only possible for Climate Scientists to understand the science have not been able to demonstrate either that this is so, nor that there is any good reason why it should be so. The more sceptical viewpoints remain intact.

    I think at the end of this exercise it will have adequately been demonstrated that there are very few things that people can agree on at all. Even the basics remain in considerable dispute, and any argument by ‘appeal to consensus’ is lame and unconvincing. Ho hum.

  41. Steve Mosher,

    I just want to quibble with a point you make somewhere in the thread above, that we should use the GCM because “it’s the best tool we have” (as if there were only one). Until one has been shown to justify usage, NO. If I have a headache, I don’t want you using a shovel, even if it is the “best” tool you have.

    • suggest another quantitative tool and I’ll put down the shovel.

      The issue is sensitivity. That aspect of the system is not calculatable from first principles. Observation can define some rough boundaries. The only ways to estimate it are:

      1. Shrug your shoulders and say its too complex and bash modelling.
      ( fun work if you can get it)
      2. Actually write a model and estimate it.

      3. Stand up and pull numbers out of your… err hat.

      • I must say that models are measured in utility, robust models come complete with estimates of uncertainty for just that reason, and dynamic reductionist modeling ain’t the only trick in town, and can suffer from diminishing returns in any application.

        So overly complex models with high levels of usually unreported uncertainty that swamp the inferences trying to be made are worth an occasional bash. Particularly when people start substituting the model for reality in experiments (again usually with no hat tip to the inherent uncertainties).

        I blame a generation bought up on computer games myself. I tell you it’s going to get worse the better the graphics get.

  42. Thanks to all for a worthwhile discussion (so far!), especially to Chris Colose for his focus on issues and his display of serious-minded geniality.

  43. If the term “we” is ambiguous, I would argue that “confidence” is equally so. Sufficient evidence has now accumulated to justify very high (>95%) confidence in the rather modest FAR conclusions. The question arises as to confidence assignable to the more definitive conclusions in AR4. Here, too, I would suggest the importance of identifying specific elements of AR4.

    Without question, uncertainties remain in regard to elements of the climate system. However, if the conclusion in question is the assignment of >90% confidence that anthropogenic activities – primarily greenhouse gas emissions – are responsible for “most” of the warming of the past 40-50 years, it is hard to find any serious evidence to contradict that conclusion. On the other hand, many within the climate science community assert that “almost all” the warming averaged over that interval is anthropogenic. This claim is certainly defensible, but does not justify the same level of confidence.

    Here, we can specify the alternatives to anthropogenic forcings that signify the differences between “most” (>50%) and “almost all”. These include residual forcing from solar increases from much earlier decades, internal variability (AMO, PDO, ENSO, etc.), declining anthropogenic aerosols or volcanism (if such declines can be documented), and unidentified elements within the totality of solar radiation that depart in trend from the flat or slightly declining total solar irradiance and extend beyond the observed changes in the UV component or effects on cosmic rays. Attempts have been made to quantify these factors. The best estimates support the “almost all” conclusion, but the error estimates make it far safer to settle for “most” warming. The possibility of a <50% contribution seems remote, but as in other fields of science, even remote possibilities are possible. On the other hand, I'm not convinced that we will soon amass evidence to reduce uncertainty much further before we experience the consequences of whatever nature has in store for us. It is probably worth proceeding with that expectation in mind.

    • Fred

      There are two issues at stake when it comes to confidence. What is the empirical confidence in the scientific explanations; and how confident are we in our beliefs. The problem with this debate is the latter tends to be much greater than the former.

  44. All of the raw data that the majority of climate science is based on has been shown to be biased and adjusted to fit a preconeived outcome. So until that little problem, (sarc.) is dealt with, how can there be any discussion on climate what so ever.

  45. Judith

    I would imagine that all the other posters on this blog know more about science and in particular climate science than I do, but if you will forgive me there are some basic questions that I need to get off my chest.

    I read in your blog:

    “Our judgement is that:
    Global – mean surface air temperature has increased by 0.3°C to 0.6°C over the last 100 years, with the five global-average warmest years being in the 1980s………..

    I just wonder why we continue to have an obsession with ‘global mean surface air temperature’.

    This last summer there were periods of unusual heat in Russia whilst at the same time there was unusual cold in South America. If the unusual hot cancelled out the unusual cold there would be no change in the global mean surface air temperature. Or to put it in other terms, no-one experiences global mean surface air temperature, so why the obsession with this metric?

    How useful is it as a proxy for climate?

    I have also heard it said that the reported rise in global mean surface air temperature is due to the fact that it is largely the minimum temperatures that are increasing (not the maximum), so we have warmer nights and warmer winters. If this is the case, I would have thought it would be beneficial for mankind?

    I have also read that there was nothing unusual about the reported rise in global temperatures at the end of the 20th century. In a statement to the British House of Lords, Lord Hunt of King’s Heath said ‘Observations collated at the Met Office Hadley Centre and the University of East Anglia Climate Research Unit indicate that the rate of increase in global average surface temperature between 1975 and 1998 was similar to the rates of increase observed between 1860 and 1880 and between 1910 and 1940 (approximately 0.16 C° per decade).’ This has subsequently been confirmed by Phil Jones. Can anyone explain why we are so uptight about late 20th century warming?

    And who decided that 1961-1990 (Hadley Centre’s base line) had the most favourable mean global surface temperatures? Is this not just a bit arbitrary?

    I have also read that temperature is not the same as heat energy and it is the earth’s heat energy budget that is important wrt climate. I think Roger Pielke Sr makes the point that SST should be the preferred metric. Is this a change that should be adopted by the climate community?

    Sorry more questions than answers

    Regards Gary

    • Gary – There are good reasons for the use of mean global temperature anomalies as a metric, as well as good reasons why these anomalies should not be the sole metric for judging climate change. There are also good explanations regarding other questions you raise. However, your questions were addressed to Dr. Curry, and I hope she will have a chance to address them before too many of us preempt the occasion.

      • Hi Gary, Fred, too swamped with testimony at the moment to reply at length, unfortunately. good topic for discussion tho

      • Fred

        Thanks for your response. My enquiry was addresses to Dr Curry as a matter of courtesy as this is her blog but I am sure she will have no objection if others seek to enlighten me.

        Regards Gary

      • When people say that without greenhouse gases the global temperature would be 255 K, and with them it is 288 K, they are really referring to the equivalent longwave energy output at the surface which has a one-to-one correspondence with temperature, but 288 K (or 13 C) is easier to relate to than 390 W/m2, which is the equivalent energy flux for a surface at 288 K. And, while global average surface air temperature is not quite the same as surface black-body temperature, it is comparable, and would rise and fall at the same rate.

      • oops, 288 K is 15 C of course

      • Hi Gary– Since Judith is busy at the moment, hopefully you will entertain other replies, since you ask reasonable questions.

        Certainly there’s many other variables (temp, precip, droughts) and statistics (mean, extremes, etc) people are interested in, but global mean temperature anomaly is a useful starting point. To begin with, I want to give a quote from Dr. Isaac Held at GFDL in a response he gave to a similar question a few years ago, and then I’ll add a few words of my own:

        ………..

        “Define some measure that you are happy with of the severity of local climate change. Take some representative set of climate models predicting the climate at the end of the 21st century given some scenario of emissions (for example the 20 models in the archive established by IPCC for the 4th assessment) and compute this global measure of local impact. Then correlate it with the change in global mean temperature across the different models. My guess is that it will correlate pretty well, with the model’s predicting larger global mean temperature responses also predicting larger local impacts.

        If your impact measure is very regional — for example, if all you care about is rainfall in the Sahel — then it likely will not correlate well with global mean temperature change (I’ve checked this one). But if your metric is an average over the Earth of the magnitude of regional climate change, then my guess is that you will see a strong positive correlation. This is the limited sense in which I think it is meaningful to use global mean temperature change as a surrogate for the local effects that, of course, we all care about — in the context of considering the implications of differing model predictions.”

        …………………..

        In addition to Isaac’s comments, I’d add that under a CO2 forcing scenario the temperature change is pretty uniform over the globe relative to other variables. There’s amplification at higher latitudes and clear magnitude differences across regions, but most areas warm and to within a factor of maybe 3 or 4 from each other. For other variables, like precipitation, the spatial heterogeneity is large, with many regions drying and others getting wetter, making the concept of a global mean precipitation anomaly a bit less meaningful. Of more interest is how gradients in precipitation patterns may be altered.

        This is, of course, forcing-dependent since it’s possible to construct some forcing (such an alteration of the thermohaline circulation) which has very minimal global T impact but has significant regional impacts. I certainly agree though that moving beyond just a global T outlook is important, but it’s a good start.

        Global Warming of anthropogenic-causes generally does cause a reduction of the seasonal and day-night temperature gradient as you mention, but there’s also the threat of hotter summers, heat waves, droughts, etc. There’s a lot of impacts of various sorts, some of the more pronounced ones are hydrologic-related and not just temperature-related….so there’s an expected distribution of positives and negatives (e.g., possibly good for agriculture in Canada, and negative for food productivity in the States). That distribution should change as the magnitude of climate change becomes larger, particularly since the rate of change is relatively large in the context of past climate shifts. This brings us into a very extensive topic of impacts (and value judgments) of which countless papers and books have been devoted to, and also an area I lose some confidence in my ability to answer more specific questions.

        On the HadCRUT baseline: no one decided it’s the best to use, it’s just a choice, and others use different baselines. It doesn’t matter.

        I’ll leave it at that for now.

      • Chris and Fred

        Thanks for taking the trouble to respond. Apologies for the delay in getting back to you, but we live in different time zones.

        Can I just pick up on a number of points if I may

        Chris you refer to Dr Held who says ‘My guess is that it will correlate pretty well, with the model’s predicting larger global mean temperature responses also predicting larger local impacts.’ Forgive me but this is not the sort of argument that I find in any way compelling. Is guessing scientific? Also note that I have very little confidence in models.

        You then say ‘Global Warming of anthropogenic-causes generally does cause a reduction of the seasonal and day-night temperature gradient as you mention, but there’s also the threat of hotter summers, heat waves, droughts, etc.’ If there is a reduction in the heat gradient (day-night / seasonal) will this not lead to less extreme weather?

        You then say ‘since the rate of change is relatively large in the context of past climate shifts’. When you refer here to climate shifts do you mean climate shifts as represented by changes in global surface temperatures? If so this seems to be at odds with the observation that there was nothing unusual about the rise in temperatures at the end of the 20th Century, a point that I note you did not address.

        Turning then to ‘On the HadCRUT baseline: no one decided it’s the best to use, it’s just a choice, and others use different baselines. It doesn’t matter’ I believe GISS use a similar baseline. As Fred points out this is to establish a base for the anomaly. So, someone did decide it was the best to use and it does matter. It matters in the same way that any statistical analysis depends on which numbers you choose to look at. The claim coming from the sceptic community is that the evidence offered by climate scientists is slanted towards a pre-conceived outcome. So it does matter.
        And ‘I certainly agree though that moving beyond just a global T outlook is important, but it’s a good start’. My point is, though, is it a good start? Does it have ANY scientific merit or is it more of a policy approach. If there was no global mean temperature, there would be no need for a ‘global’ approach to mitigation. Given the acknowledged problems in creating an accurate dataset for a body as large as the earth that has been subject to countless wars, pestilence and natural disasters over the period of the record and given controversies with UHI, station moves/drop-out and data manipulation this is always going to be an area where climate science is going to struggle to persuade.

        Fred says ‘Regarding SST, this tracks global temperature anomalies rather faithfully, not surprising given that about 70 percent of the surface is ocean and that most of the world’s heat is stored in the ocean.’ Is this not an example of the evidence being presented in a slanted way? Is it not the case that global temperature anomalies track SST, a subtle but very important difference?

        I do not know if you guys will see these comments as our host has moved on to other things, but I thank you again for your time and trouble

        Regards Gary

      • Gary, I will eventually do a series of threads on surface temperature, also on natural climate variability

      • Thanks Judith

        it is an area where I think progress can be made

        Regards Gary

      • Gary– if you want to discuss this with me, you’re going to have to drop the whole “we want a slanted outcome” sound byte. If the only arguments people have are conspiracies it’s not going to be a very good dialogue. The only good thing about blogs is that you’re allowed to make baseless allegations without any evidence and unless you actually have some stature in the field no one is going to care much. Please don’t take advantage of the internet outlet to get away with this.

        The global temperature change doesn’t care what your “zero” point is. It’s warming regardless. If you choose an arbitrary zero point at “-10” and move to “-9” it’s just as much change as going from “7” to “8”, and biological systems, or whatever else doesn’t care about our definitions. It’s probably a good idea to choose a baseline with relatively little change (as in the 1951-80 climatology like GISS does, and with good observations). This isn’t very complicated and there’s no secret conspiracy in these choices, and this information is all accessible online.

        There’s more questions you asked but I’m getting the sense you’re not really in a learning mode right now as much as an accusation mode. When you shift your thought process I’l be more willing to engage in the future.

      • And if there is cooling, is this “cooling” or “not warming at that moment”?
        Even if the record has been manipulated to “hide” cooling? C’mon.

      • Gary – Just to add one small point to the comprehensive responses already given, climate science is generally not interested in tracking “global temperature”, which is not a terribly meaningful statistic, but rather global temperature “anomalies” (as well as regional temperature anomalies and separate land and sea surface temperature anomalies. The term refers to the difference between the measured temperature at any given time and the baseline temperature (which can be chosen somewhat arbitrarily). In essence, each location is compared with itself at an earlier time. This provides useful information about what is happening regionally as well as globally. Regarding SST, this tracks global temperature anomalies rather faithfully, not surprising given that about 70 percent of the surface is ocean and that most of the world’s heat is stored in the ocean.

      • Fred

        I have replied to both you and Chris. If I understand how this works that reply will be above in the thread

        thanks for your input

        Gary

  46. Phillip Bratby

    You are right about global average temperature being an unscientific and meaningless metric. Temperature is an intensive variable and so you cannot determine an average value. For example, if your house has seven rooms of different sizes with known different temperatures in each room, can you say what the average temperarture is? No.

    Energy is an extensive variable and is what should be used.

  47. The unequivocal detection of the enhanced greenhouse effect from observations is not likely for a decade or more

    I think that except for the above quote – the FAR was very reasonable.

    I would suggest, that we are still waiting for unequivocal detection of AGW – as the signature is still smaller than natural variation.

  48. I agree that there has not been much added. But like all of the IPCC reports there is little mention of natural variability and its role in climate variability.
    Peter W

  49. vukcevic, sorry, what is the North Atlantic precursor? Iapetus? It’s not explained in the graphs nor anywhere I could easily find.

  50. Sorry, Latimer, you won’t be handed what you want on cable news.

    But you can get what you want if you’re willing get off the computer and poke around. There are plenty of good books out there besides Archer’s (which Chris recommended and which you’ve all read, of course): Alley’s “The Two Mile Time Machine” (a great read); Emanuel’s very short “What We Know About Climate Change”; Weart’s “The Discovery of Global Warnig” (available on the web); Henson’s “The Rough Guide to Climate Change”; even Kolbert’s “Field Notes From a Catastrophe”.

    Chris Colose gives good advice. I shudder everytime I see somebody say “I decided to look into the science myself so I started reading the blogs…”

    You can’t learn climate science from blogs; too much noise, too many “opinions”, too much nonesense. It’s like learning economics by reading the Letters to the Editor. People like Chris and Fred Moolten, who take the time and have the skills to explain, are rare.

    Also, browse the journals at the AMS website:
    http://journals.ametsoc.org/
    Check out Wiley’s Interdisciplinary Reviews: Climate Change:
    http://onlinelibrary.wiley.com/journal/10.1002/(ISSN)1757-7799
    See what scientists are actually doing. You can still learn a lot even if you don’t understand everything.

    Paywalled? Try:

    Dear Dr. Zorch – I would greatly appreciate a reprint (or pdf) of your article “Why AGW is a Hoax”, published in J. Irreproduc. Res., Vol. xx, pp. 888 – 999.
    Yours truly, Trian Toulern

    Don’t understand a point? Formulate a thoughtful, specific question that shows you’ve read their work and inquire of the author. Don’t badger with multiple requests; ask for helpful references “if you are too busy to respond in detail”. (Try to avoid “I read on the web that…”)

    Most scientists are too busy to hang around these blogs, but they are very happy if people are really interested in their work.

  51. Malcolm Miller

    The ‘world lightning map’ shows NO lightning over ther oceans. Are we really supposed to believe that there is no lightning at sea? The omission makes the map meaningless.

  52. Malcolm Miller

    Without the use of huge qualtities of ‘fossil fuels’ we would never be able to send anything into space. Even rocket engines using only hydrogen and oxygen are built and fuelled and transported using oils. It seems to me that there are people who would like to confine us to Earth – and a stone age earth at that!

    • The disturbingly consistent misanthropy that many in the AGW community embrace is something that deserves to be highlighted at length.
      Perhaps the most egregious example of this was Hansen’s initial unsolicited endorsement of ‘Times Up’, a book that rationalizes massive levels of terrorism and sabotage to destroy the industrial technologies of humanity.

  53. Someone please close the italic tag . There. Hopefully it worked

  54. We know climates have changed as long as there have been climates.
    We know that the risk is great cooling and glaciation.
    We know that temperatures have risen some in the last 150 years or so.
    We know that no terrible changes in cliamte or weather patterns have occurred during that time.
    We know that CO2 helped with the current round of climate change.
    We know that the current state of the climate is not more dangerous or extreme than past climates.
    We know that we have spent > $50 billion dollars pursuing this topic.

  55. The paper by Gerlich & Tscheuschner raised the issue that the physics describing CO2 on climate change were misapplied as the boundries for the equations were exceeded. I posted on an earlier thread similar suggestion and was told by Eli Rabett that the arguements by G&T were a joke and I should Google: Tscheuschner, which I have read and then re-read the original paper for the 3rd time. I did not see a deconstruction of the paper. I saw ad hominem and commentors who said they did not read the full paper, but I didn’t see a deconstruction. Relevant for me, the paper says that the physics as used in GCM are not applicable outside of the constraints of the how the equations were derived: ie, they have limits. When applying the equations of the physics to phenomenon which are very large, chaotic and related to a sphere there are large errors. G&T develop their arguement stepwise, and I admit reading their paper requires a bit of patients. Nevertheless, my request is a formal deconstruction of this paper, either currently available or yet to be developed. To me at least, this paper says that the equations for the physics upon which GCMs are based are not valid. If so, then “what we can all agree upon” is frought with the same errors as the “consensus” meme.

    • RiH008, see our paper in IJMPB (Halpern et al 2010) where we show many of the issues in G&T. For the most part it’s not an argument about climate, it’s a misunderstanding of thermodynamics, and an absurdly long amount of time dedicated to discussing things which are well known like “the greenhouse effect doesn’t work like a real greenhouse.” The best is their housewife with a pot of boiling water example of why the greenhouse effect isn’t real. Eli categorizes this paper properly.

      • Thank you. I couldn’t get past the paywall although I tried several avenues.
        Is there another way to get at that issue since it contains the G&T rebuttal? Obviously the abstracts are not sufficient.
        Regards

  56. Judith: “The main greenhouse gas, water vapour, will increase in response to global warming and further enhance it.” This statements is only certain to be correct for areas where water vapor is known to be in equilibrium with liquid water. The only place where this equilibrium exists is in the boundary layer over the oceans. In regions where the air is rising and has recently been in contact with the boundary layer and through which rain has been falling, it appears reasonable to speculate that water vapor will increase with warming. By the time rising air gets to the tropopause, it is absurd to assert the water vapor must be in equilibrium. Subsiding regions of the atmosphere have been in contact with the tropopause more recently than the boundary layer. So the statement appear to be correct for only part of the atmosphere. When you consider that the coldest, driest region of the troposphere is directly above the warmest, dampest region of the troposphere, it seems likely that increases in deep convection could reduce the amount of water vapor in the air.

    • Frank, your idea is not unreasonable. In fact, it resembles Lindzen’s old negative feedback hypothesis (of drying of the upper troposphere) in the early 90s, although he has since abandoned that in favor of the IRIS idea.

      The upper troposphere is the key target to look at for water vapor feedback, especially in the tropics, and many key thermodynamic arguments which constrain relative humidity in the boundary layer don’t hold well in the free troposphere. Yet the changes are still far too small to overcome the saturation vapor pressure dependence on temperature, and a moistening of the upper atmosphere has been borne out by observations (it is at least a credit to Lindzen that he has departed from this hypothesis). There’s many articles which discuss this, including Held and Soden 2000 and 2006, Pierrehumbert et al 2007, and various works by Tapio Schneider and Andrew Dessler for some of my favorites.

      • Judith was discussing the FAR which probably drawn a conclusion about water vapor feedback that relied upon equilibrium considerations in places where equilibrium does not exist. I am interested in observational “proof” of water vapor feedback; Held and Soden 2006 is all about models. Soden 2005 is observational evidence and I would have mentioned it in my first post if I wasn’t so rushed. The summary of other observational evidence in Ar4 is very thin and the recent papers you mention don’t stick in my mind. My impression (without re-reading everything) is that AR4 (& Soden) concluded that the observations were (“likely”?) more consistent with constant relative humidity than with constant specific humidity – which falls far short of a usefully-constrained value for water vapor feedback. It does suggest that increased water vapor does survive a round trip to the tropopause. If there is any observational evidence stronger than Soden 2005, I’d be interested.

        SOD discussed Ramanathan’s early Science paper (ca 1990) on water vapor feedback. The analysis only covered clear skies. Suspiciously, no one seems to have applied the method to other data sets and Ramanathan only analyzed data from one of several years. From my amateur perspective, this could be a way to get a handle on water-vapor feedback in clear skies, exactly where the assumption of constant relative humidity is least likely to be correct.

  57. I am bothered by the IPCC citing the 100 year rise in temperatures as proof of the AGW model, when all the attribution studies assume forcings only increased after the 1970s (more or less). This is like taking credit for things that happened before you were born.

    • //”I am bothered by the IPCC citing the 100 year rise in temperatures as proof of the AGW model…”//

      I am bothered when people just make things up and pass them off as being skeptical of the original idea…

      • Craig Loehle isn’t making things up. He is correct in stating that the IPCC cites a 100-year rise in temperatures (“the total temperature increase from 1850–1899 to 2001–2005 is 0.76̊C”) and also broadly correct in stating that “forcings only increased after the 1970s (more or less)”. According to the GISS forcing estimates, which are substantially what the IPCC uses, almost 90% of the 1.7 watts/sq m increase in total anthropogenic forcings between 1880 and 2003 occurred after 1950 and 70% of it occurred after 1970 (http://data.giss.nasa.gov/modelforce/).

        He might also have mentioned that the disconnect isn’t just limited to temperatures. The same problem exists with sea levels, which have been rising at reasonably constant rates for at least the last 100 years, and with glaciers, which have been in worldwide retreat for at least the last 150. (http://hal.archives-ouvertes.fr/docs/00/29/85/23/PDF/tcd-1-77-2007.pdf)

        What Craig has done is put his finger on a major flaw if not in the AGW theory itself, then at least in the way it’s presented. Rising sea levels, rising temperatures and retreating glaciers are arguably the most commonly-cited “proofs” of AGW, yet if our forcing estimates are correct they all began long before human impacts on the climate became significant.

      • Both CO2 and solar forcings became evident after the mid-1800s, and the temperature record is consistent with those forcings. A significant solar forcing has been absent from the post-1970 record, which is why the trend before the middle of the twentieth century can be apportioned between the solar and CO2 influences, but CO2 predominates among the influences of the past 40 years.

        The rate of land ice melting (from glaciers and the Greenland and Antarctic ice sheets) has increased substantially over earlier intervals, and as a consequence, the rate of sea level rise has also increased. Measurements are more accurate since the inception of satellite altimetry monitoring, but based on the best data available, the recent trends of 3mm/year since the 1990s exceed those derived from tide gauge measurements of earlier twentieth century decades. One can legitimately refer to uncertainties regarding all these measurements, but there are no inconsistencies between observations and the principles underlying anthropogenic influences.

  58. I believe this approach is putting the cart before the horse.

    The first thing to establish is the natural condition, the controls thereof and the natural forecast prognosis, assuming that we represent mere fauna, disregarding any environmental disturbance or resource exploitation.

    It would appear that the natural condition is geologically atypical, and unstable. We find ourselves in an ice age, within but near the end of a brief interglacial thermal respite. Despite this respite, natural CO2 atmospheric concentration and global temperature is very low, perhaps even critically low, compared to the bulk of geological history. Clearly the ancestor stock of all life forms today thus evolved and acclimatised in their phylogeny in warmer higher CO2 concentrations in a so-called ‘greenhouse’ dominant world. It is therefore illogical to assume that higher temperatures and CO2 concentrations threaten the survival of the Earth’s biota, rather the reverse.

    Be that as it may, it behoves us to understand first the precise controls and mechanisms causing the ice ages and the interglacial stands and interstadial spikes. And then to be able to precisely predict the timing of future switches in warm/cold ‘polarity’.

    Do we have high confidence in these controls? No.
    Can we predict with confidence the timing of future switches? No
    Should these be a research priority? I think yes.

    Since we are in the interglacial situation, the ultimate Sword of Damocles dominating the fate of humanity is the commencement of the next glaciation. In comparison, ‘global warming’, true or false, is a triviality.

  59. Judith: “Have there been any serious challenges to these statements? .. Are these the statements that pretty much everyone can agree with?”

    AR1: “We are certain of the following: … emissions resulting from human activities are substantially increasing the atmospheric concentrations of the greenhouse gases carbon dioxide, methane, chlorofluorocarbons (CFCs) and nitrous oxide These increases will enhance the greenhouse effect, resulting on average in an additional warming of the Earth’s surface. The main greenhouse gas, water vapour, will increase in response to global warming and further enhance it”

    We can easily observe unsupported mass falling to the floor in the laboratory. We do not therefore insist that all unsupported mass must immediately fall to the ground. Laboratory observation don’t immediately translate to all observations outside the idealised laboratory conditions. Why then simply take it for granted that such an extrapolation may be made for the GHE?

    Climate sensitivity is concerned with response to a change of some aggregate measure of the composition of the atmosphere. It is therefore concerned with the slope of climate response to GHGs, not the absolute response.

    Ferenc Miskolczi argues that the greenhouse effect is saturated by the water vapour response. His case is presented in a form which should be familiar to practitioners. As it challenges the above AR1 assertions, we may not conclude that pretty much everyone agrees.

    According to Miskolczi, the incremental response to all GHG’s is equal. In a state of saturation, there is no incremental climate response to any of them. Water vapur fully compensates (it is a strong negative feedback in the engineering and mathematical sense).

    I should like to see Miskolczi’s work being subjected to full scientific discourse and testing. It deserves much more than knee-jerk replies and slap-downs in the blogosphere. Has anybody formally replied to Miskolczi in detail in the literatire? Has anybody applied for a grant to examine the processes and responses? (Such as formal detailed analyis of trends in RH). Serious questions – not just rhetorical.

    In addition, Chapter 9 of TAR provides an elaboration of the purported climate repsonse, with the predicted observation being presented graphically in Figure 9.1. This should already be evident if any past warming can be attributed to the physical processes behind the enhanced GHE. If the pattern of warming is not already supported by observation, this may be viewed as another serious challenge to the above AR1 statement.

    • Has anybody formally replied to Miskolczi in detail in the literatire?

      this?

    • Frank – Miskolczi’s analysis has been subjected to numerous critiques and has been found deficient in several areas. These include his misunderstanding of Kirchoff’s Law, and his failure to distinguish between equilibrium scenarios and those involving radiative imbalances. However, the most decisive refutation comes from climate observations themselves. Miskolczi’s stabilization hypothesis requires a warming tendency mediated by increasing CO2 to be offset by a compensating reduction in atmospheric water vapor. The notion that warming will cause water vapor to decline appears to conflict with predictions from both models and basic physical principles. Nevertheless, nature sometimes surprises us, and so the true test entails actual water vapor measurements. These show an increase in parallel with the warming climate, invalidating the Miskolczi theory.

      Regarding TAR Figure 9.1 and its prediction of temperature increases consequent to CO2 increases, I see no conflict with observations. Remember that CO2 is only one of multiple forcing agents affecting temperature, with anthropogenic aerosols providing a negative forcing that partially reduces the CO2 effect. This is well demonstrated by the various GCM hindasts, which start with an earlier climate and then project changes without or without the observed increases in CO2 and aerosols, but including natural variability. The models reproduce the observed changes well when the anthropogenic factors are included, but do not come close when they are omitted. (Note that despite misconceptions perpetuated in some parts of the blogosphere, the models are not “tweaked” after the fact to make them coincide with observations. Their ability or lack of ability to simulate the observed changes is an unalterable feature of the model at the time the CO2 data are applied to it).

      • In writing my above comment, I failed to notice that gryposaurus had already provided a link to a detailed refutation of Miskolczi that is worth visiting.

      • Fred Moolten: “Miskolczi’s analysis has been subjected to numerous
        critiques and has been found deficient in several areas.”

        Ciitations please. From the literature (Please don’t bother reporting what RC has to say about it).

        Fred Moolten: “However, the most decisive refutation comes from climate observations themselves … the true test entails actual water vapor measurements. These show an increase in parallel with the warming climate, invalidating the Miskolczi theory.”

        Citations please. Please stick to the literature – preferably articles which directly address Miskolczi’s analysis and present their own observations (if there are any).

        Without citations you have not answer my question and it just appears to be more handwaving on the blogosphere.

        Fred Moolten: “Regarding TAR Figure 9.1 and its prediction of temperature increases consequent to CO2 increases, I see no conflict with observations.”

        Without wishing to be too disrepectful, what “you see” does not meet the standards that I have asked for. It take it as confirmation that you cannot cite observations of the predicted pattern of warming in the literature.

        The remainder of your post is handwaving about models and model results. I phrased my questions with the specific intention to avoid that.

      • Jordan – I don’t think I have the time to do your homework for you. You can find extensive literature on the rise of atmospheric water vapor paralleling the rise in temperatures, as well as extensive literature demonstrating the consistency of temperature measurements with predictions as in TAR Fig. 9.1. Start with the references in AR4 and proceed from there. – you’ll find many on atmospheric water vapor. I’ve also discussed this in reply to ivpo below, again directing him to references. I doubt that many authors have bothered to refute Miskolczi in the published literature, because the observational data on water vapor clearly invalidate his theorizing without a need to write a paper about it, and because even skeptics among the climate science community don’t take his work seriously.

      • Usually when you don’t even know the difference between “absorption” and “absorptivity” or grasp Kirchoff’s law, and the virial theorem you won’t be taken seriously. Not everything needs a “published response.” This isn’t a game of last words.

      • Ferenc Miskolczi

        Chris – Where are you with your study? I do not see much progress. Absorption…emission…??? Why do not you have a look at this link:
        http://science.larc.nasa.gov/ceres/STM/2005-11/miskolczi_airs.pdf

        you may learn something about radiation.. absorption bands and similar other thinghs ….Could be good reading to Fred Molten too. On the other hand, I do not think that this blog is about the qualifications of the participants…

      • Fred Moolten: “… the true test entails actual water vapor measurements. These show an increase in parallel with the warming climate …”

        The “a detailed refutation of Miskolczi that is worth visiting” [not peer reviewed]: “Moreover, there is ample observational evidence that the most important greenhouse gases, water vapour and carbon dioxide have increased in the last four decades, meaning that the total infrared optical depth is indeed increasing”

        Actually no that was a wrong assumption from IPCC reports see this from peer reviewed literature:
        http://www.theclimatescam.se/wp-content/uploads/2009/03/paltridgearkingpook.pdf

        and this calculates and shows the consequence of the above paper on the optical depth:
        http://www.eike-klima-energie.eu/uploads/media/EE_21-4_paradigm_shift_output_limited_3_Mb.pdf

        This issue has the recent paper from Miskolczi and a note about an earlier one from Noor van Andel.

        Thus the real observations actually support the theory and you can check that data for yourself here
        http://www.esrl.noaa.gov/psd/cgi-bin/data/timeseries/timeseries1.pl

      • The increase in atmospheric water vapor is now well documented by 4 out of the 5 reanalysis datasets as well as recent satellite monitoring. The inaccuracy of the NCEP reanalysis, which utilized only radiosonde data with documented measurement biases is well known in the literature, but apparently unrecognized in some parts of the blogosphere that still cite those data. I won’t go into details but part of the problem was a delay in terminating humidity measurements, leading to a positive humidity bias. As the instruments improved to reduce the delay, the bias was reduced, creating a spurious trend of decreasing humidity. The satellite data avoid this error.

      • Fred Moolten:

        The increase in atmospheric water vapor is now well documented by 4 out of the 5 reanalysis datasets as well as recent satellite monitoring.”

        Really there is no argument about the increase in specific humidity in the lower troposphere, hence the total SH, so what is your point?

        The NCEP data shows that quite clearly if you had take the trouble to look. It’s the effect on the atmospheric optical depth of the reduced specific humidity in mid to upper troposphere where the effect becomes more pronounced that is at issue. You do understand this don’t you?

        “The satellite data avoid this error.” This must be a little more difficult for you to grasp but the TIGR data set (used in Miskolczi 2007 ) among others are radiosonde data sets used for calibration (training neuronets) of the satellite instruments to measure water vapour. Now if there is a problem with those data sets how do you think the satellite instruments calibrated with them are going to avoid those problems?

        If you think you have a better data set not dependent in any way dependent on radiosonde data why don’t you present it?

      • The humidity increase is documented for the mid-upper troposphere as well. The problem with the NCEP reanalysis relates to changes in instrumention over multiple decades (downward jumps following each change in instrumenttion), and not to radiosonde data per se.

        Some further descriiptions can be found in Dessler and Davis as well as extensive references to the satellite data in AR4.

      • Fred Moolten:

        Thank you for the link to the abstract of Dessler and Davis others might find it useful but I have the whole paper on several hard drives around the place including in long term storage. I don’t know why I have kept it as I don’t give it a lot of credence. and we were aware of it before Miskolczi 2010 was written. There are several reasons why:

        1.

        … and there is a growing consensus within the scientific community that the water vapor feedback is strong and positive.

        I’m sorry but positive feedback and/or amplification (you can’t really have one without the other) to a dissipative system is like Laetrile to cancer cures. Now perhaps you can show that the climate system isn’t a dissipative one (or has an internal/auxiliary power source to overcome the losses, if you can then you should do so.

        2. The trend plots of the 5 reanalysis are wildly different from each other they can’t all be right and at least 4 out 5 must be wrong. There is a Talmudic saying:

        the mouth that binds is the mouth that looses.

        IOW I’ll go with the ones for whom the data they present is to their disadvantage. Since a negative trend in mid to upper troposphere specific humidity is to the disadvantage to NOAA climatologists who would like support for that spurious positive feedback I would go with NOAA data.

        3. Like a said earlier the satellite instruments were checked against radiosonde data (as was the spectral data from the satellite instrument that you may see here

        I could go on but I think you have enough to chew on.

      • From the above, I gather that you haven’t yet been dissuaded from your earlier-expressed views that CO2-mediated warming violates the Second Law of Thermodynamics. I won’t try further, and you are welcome to ignore the positive humidity trends in 4 out of 5 reanalyses as well as satellite radiance data also showing the humidity increases in both lower and upper troposphere. At this point, it’s best to let others review all of these comments to make their own judgments about Miskolczi and about the Second Law, because neither Miskolczi nor the Second Law appear to warrant much more in the way of extensive discussion in the views of most of the rest of us, and your views aren’t going to change.

  60. I suppose it could be worse. What if someone earlier up had dropped a different HTML tag and the entire discussion ended up in “scare quotes”.

  61. Dr Michael Cejnar

    Dear Chris Colose
    I remain hopeful of a helpful response to even one of the six questions troubling me and skeptics about AGW ( I understand Dr Curry is busy) . While I am skeptic, I do have two young kids, so I do visit Warmist blogs in case I am wrong or new evidence has arisen – but like with religion, I don’t find firm arguments based in reality, but instead, a lot of human frailty. I was hoping for more on this blog.

    I agree that many bloggers (on both sides) are ignorant. While I also sympathize with your request that they should have to read climate theory before they to speak to you, this does not serve your purpose (nor does your use of the “..evolution-creation wars” simile).

    The Climatologists have in effect said to mankind – I am >90% certain you have a terminal cancer called Climate Change and you must have radical surgery immediately. The doctor has authority, and some patients will accept this on faith. But some patients are physiotherapists, nurses, doctors themselves, others are physicists and many are far more intelligent than the doctor. The patient has a right to demand a coherent explanation in terms he can understand and needs to be confident that the doctor is objective, competent & impartial. If the doctor cannot explain it logically, if he discovers the doctor is exagerating certainty of even one test, if he is cought out being untruthful about even one detail, if he is sloppy and lost your test, if the doctor owns the company supplying the radical treatment, or if the treatment has only been tested on mathematical models, the patient is right to hesitate.

    Doctors have learned a long time ago not to say – “Look, you are not qualified to understand this, so you have no say in this”. Seems Climate Scientists have yet to learn this.

    There is of course one other possible reason why you are failing to persuade the public other than just poor communication….

    • Michael – Reasoning by metaphor has its limits, but in any case, I would suggest that the empirical evidence supporting a significant positive feedback amplification of CO2-mediated warming is substantial, and spans more than 400 million years of climate data. If you were to argue that the evidence does not constitute absolute proof, no-one will disagree, but the evidence involves data comparing temperature changes with known changes in CO2 and other variables, and is compelling.

      Regarding your other questions, this blog can’t serve as a comprehensive treatise on the entire climate change process, so I will be reasonably brief, suggesting that further information is available in the published literature (and to some extent on the Web).

      Much of Lindzen-Choi-2009 has been retracted by these same authors in a 2010 draft that apparently has not yet been accepted for publication. The new version is better, but still fails to provide any evidence regarding long term feedback responses to perturbations arising in the atmosphere, such as CO2 increases. It focuses on very short term responses to temperature changes originating in the ocean, which bear no necessary relationship to atmospheric perturbations.

      There is no “e-folding time” for excess CO2 in the atmosphere, which does not follow a simple exponential decay curve. Rather, a small fraction equilibirates within decades, whereas other fractions subside over intervals ranging from centuries to hundreds of thousands of years (the latter for the weathering of silicate rocks). The IPCC is not the best data source for this, but David Archer among others has published on the subject. From the perspective of a human timescale, much of the excess CO2 can be thought of as “forever”.

      Tropospheric amplification (the “hotspot”), as you indicated, is a response to any type of surface warming, not merely CO-mediated warming, and it a response predicted by basic physics rather than originating in climate models. It is demonstrable when short intervals (e.g., a few years) are examined, but has been elusive with data over many decades. As instrumentation has improved, the disparity has lessened, and so it is likely that much of the difference reflects measurement problems. To the extent that we ultimately find less amplification than predicted, we may be forced to conclude that climate sensitivity to CO2 is greater than currently estimated (i.e., the positive feedbacks are even more dominant), because the “hotspot” is a manifestations of a negative feedback – the lapse rate feedback. At this point, however, I expect that most of the unresolved difference will turn out to reflect measurement issues.

      The warming trend observed over the past century has inevitably been characterized by ups and downs over shorter intervals, due mainly to internal variations but also to some anthropogenic factors such as aerosols. The most recent decade is the warmest on record, and 2010 is destined to be either the warmest year since record-keeping began, or close to it. Climate models are known to be much less precise in matching short term trends than the multidecadal trends since the early 1900s. High confidence is justified for the long term, but less justified for shorter trends.

      Your question 6 appears to be a composite of topics spanning much of climatology, and you shouldn’t expect details here. Clouds are thoroughly addressed in the climatology literature, and acknowledged to be a source of uncertainty, but not enough to seriously challenge the evidence for net positive feedbacks over the no-feedback Planck response. The other factors you mention have been quantified and fail to explain more than a small fraction of the warming of the past 40 years. I’m afraid you’ll have to visit the published literature if you want a more detailed analysis than a blog thread can accomodate. If you do find published data that you believe have been overlooked, I hope you’ll bring them to our attention. In particular, if you can link to a full-length article that was published in the peer-reviewed literature, that would be helpful. Otherwise, it would be useful to cite the authors, title, journal name, volume, page numbers, and year, so that we can dig out the reference for ourselves.

      I realize that to address even one of your questions with the full weight of evidence would require far too much column space than is available here, which is why referring you to the literature is not an evasion but a necessity. What I have done above is indicate that your questions are not ignored within the purview of climate science, and their answers are compatible with current views of how the climate responds to CO2 and other greenhouse gases.

      • Re Fred Moolton: “I would suggest that the empirical evidence supporting a significant positive feedback amplification of CO2-mediated warming is substantial, and spans more than 400 million years of climate data. If you were to argue that the evidence does not constitute absolute proof, no-one will disagree, but the evidence involves data comparing temperature changes with known changes in CO2 and other variables, and is compelling.”

        Mmmm, I gotta disagree with this Fred. The pure radiative physics of CO2 is very compelling. The evidence for significant positive feedback amplification of CO2-mediated warming is weak. I would say very weak. This is the fundamental question really and we don’t know the answer. Without significant positive feedback amplification to rising CO2 there is no catastrophic warming. In 300 years of melting global ice and 150 years of man pouring CO2 into the atmosphere we cannot detect a positive feedback amplification signal in our climate system.

        Dr Michael Cejnar points out that a well informed patient wants to make sure that the proposed radical surgery will not be more invasive than the disease . This is an accurate analogy in regards to current climate science and demonstrates the importance of carefully separating what we know from what we don’t know.

      • Ivpo – You state, “The evidence for significant positive feedback amplification of CO2-mediated warming is weak… In 300 years of melting global ice and 150 years of man pouring CO2 into the atmosphere we cannot detect a positive feedback amplification signal in our climate system. ”

        Could you specify what signal you had in mind that you fail to see in the evidence, or better yet, can you cite specific publications in the literature identifying the signal you believe to be missing? I say that because the observational data appear to be quite consistent with positive feedback amplification of both positive forcings (e.g., CO2) and negative forcings (aerosols), which combine to yield the measured temperature trends.

        However, the evidence for positive feedback extends back far earlier than the past 300 years and is substantial, even if not 100 percent conclusive. For a beginning foray into the very extensive literature on this issue, you might want to look at chapter 9.6 of AR4 to read the text, and even more importantly, to view the references that can give you further details. The link is
        Climate Sensitivity

        I haven’t seen compelling published data refuting what is in those references, but if you are aware of any, we can review it. Recent attempts have been made to demonstrate low climate sensitivity by Spencer and by Lindzen and Choi. Analysis of these is a separate topic; they appear to exhibit significant flaws, but in any case are irrelevant to long term feedbacks mediated by changes in atmospheric components such as CO2. As far as I know, the evidence for positive feedback responses to CO2 and other perturbations originating in the atmosphere is robust.

      • Sure. From your link:
        “Since observational constraints on the upper bound of ECS are still weak (as shown below), these prior assumptions influence the resulting estimates.”
        And:
        “Methods that incorporate a more comprehensive treatment of uncertainty generally produce wider uncertainty ranges for the inferred climate parameters. Methods that do not vary uncertain parameters, such as ocean diffusivity, in the course of the uncertainty analysis will yield probability distributions for climate sensitivity that are conditional on these values, and therefore are likely to underestimate the uncertainty in climate sensitivity. On the other hand, approaches that do not use all available evidence will produce wider uncertainty ranges than estimates that are able to use observations more comprehensively.”

        Climate sensitivity and feedbacks are the areas of climate science with the highest uncertainty and the most compelling questions. We know from paleo studies that feedbacks do take place and that climate has changed rapidly in the past (both warming and cooling) through natural variability. In a dynamic climate with influences by solar and oceanic variability, changes in water vapor and clouds, and biological response, we have yet to identify, measure and quantify a positive feedback mechanism tied to rising CO2. Or did you have a link to a study I am unaware of with much tighter bands of uncertainty than AR4?

        The goal being to carefully separate and clarify what we know from what we don’t know.

      • No, the uncertainty estimates in AR4 remain relatively unchanged. Note, however, that as AR4 states, there may well be more uncertainty at the upper limit of climate sensitivity than the lower limit, and so the usual range of 2-4.5 C for doubled CO2 (with 90% confidence limits) might fail to include a much higher sensitivity more often than a much lower sensitivity. In fact, the latter appears to be highly improbable (although again, not completely excludable). The range, while indicating considerable uncertainty, encompasses only net positive feedbacks. It’s unlikely we will greatly narrow the range in the near future, and so it appears prudent to make decisions on the basis of a very likely but not certain range of 2 to 4.5 C.

        I would commend the references in AR4 to other readers interested in this topic as well.

      • I guess we will just have to agree to disagree. History shows that climate feedbacks both positive and negative can and do take place. A positive or negative feedback to man made GHGs is certainly within the realm of possibility. Actually observing and measuring a positive feedback response to CO2 and separating that response from natural solar, oceanic, water vapor, cloud, and biological variability? I don’t see it anywhere. Certainly not within AR4. I do differentiate actual observation and measurement from theoretical model results when considering the robustness of the evidence.

        This question may simply come down to our different tolerance for confidence levels and our willingness to act on those levels… which is the point of this thread.

      • Bunk.
        There is only faith-based evidence for a strong positive feedback from CO2.
        The rest of your post is a waste of bytes.

    • “I agree that many bloggers (on both sides) are ignorant. While I also sympathize with your request that they should have to read climate theory before they to speak to you, …” – Dr Michael Cejnar

      I don’t think that is what he said. Early in the thread Rod B, I believe in response izen, said some of izen’s points were, my word, lessening his skepticism. In response to the list of points you made in your post, Rod B indicated he was becoming more skeptical.

      All Chris Colose told Rod B was he might be better able to sort out blog debates if he would read some books a book about climate science.

      That was hardly offensive. I would say he was being helpful. Perhaps he did not see a question there he could answer.

      If you look through the thread, a commenter named mike actually thanked Chris, after prolonged back and forth, for helping him with some feature of climate science – I think water vapor. He has answered a slew of questions in this thread, and I bet he’s just as busy as Judith Curry is.

      My dad practiced medicine for more than 50 years. He never allowed a patient to have a say in anything.

      They could bark, or oink, or moo, or cluck, or meow, but none of them ever got to talk.

      • My sensitivity to blog ‘forcings’ is high! Probably too high, which is why I keep swaying between the two camps. However, regarding Chris’ suggestion that I read a book on climate science, it was taken in the same spirit that the suggestion was made. Certainly no offence was taken. Regards, Rob (not Rod)

      • JCH: I have on occasion had the misfortune to consult with doctors like your father I only did it once and refrained from recomending him/her to anyone else.

      • Please re-read JCH’s last sentence very carefully. He is not saying what you think he is in his penultimate one.

      • Yes I know his father was a vet, I realised it just after I posted but nevertheless, as an RN since 76 I have come across doctors who are not as nice to people as JCH’s dad would be to a dog.

    • I wish I had written that so clearly and compellingly.

      Dr Michael – I applaud you! You have said it so well.

      And the longer climate scientists and their fellow travellers in policy and lobbying and funding and all the rest of the kit and caboodle fail to appreciate your points and clean up their act, the more public faith in AGW ..and in the measures proposed to mitigate or prevent it… will reduce. It is already plummeting. Soon it will be limited to a few committed Greenies alone.

      Their choice, their call.

    • Doctors have learned a long time ago not to say – “Look, you are not qualified to understand this, so you have no say in this”. Seems Climate Scientists have yet to learn this.

      The paternal attitude of British medicine is patronizing, vain, insulting, unnecessary and reeks of hubris.

      It’s almost as dumb as the American model of ‘Admit an error or make an unfortunate ‘informed expert guess’ and get your arse sued off for having taken responsibility.

      Of course the convenience of having 10 layers of interested parties, each insisting upon exercising their desire and need to control and decides for themselves in their own self-interest does a good job of hiding (mitigating) responsibility for decision making.

      It also helps to inflate to cost of health care more than all other reasons combined.

  62. “We are certain of the following:

    there is a natural greenhouse effect which already keeps the Earth wanner than it would otherwise be”

    Well, virtually everyone was certain that Newton’s important equations were exactly correct….until Einstein proved otherwise.

    I suggest that a good scientist should be “certain” about very little. Perhaps “convinced for the time-being?”

    There is now quite a bunch of scientists out there that don’t even accept the conventional greenhouse gas theory: http://hockeyschtick.blogspot.com/2010/06/physicist-co2-greenhouse-effect-is.html

    Remember that we even have all kinds of empirical evidence for Newton’s Laws. But we have NONE for the greenhouse effect.

    Just how “certain” can one be about something for which no empirical evidence even exists?

    • Well, virtually everyone was certain that Newton’s important equations were exactly correct….until Einstein proved otherwise.

      But Newton’s equations worked in the real world and continue to be used today. No doubt our current understanding of the climate will prove to be “wrong” in many ways, that doesn’t mean that the level of knowlege we have now cannot give us a meaningful insight into the way our climate operates.

  63. What we know with confidence?

    … that we are blindly stuck in tunnel vision.

    • And who built the tunnel and who is claiming it is the path through the mountain?
      Not the skeptics.

      • Everyone builds tunnels. It’s inescapable.

        Speaking personally as I have very little sense as how it is for others …

        Some people (more or less) occasionally (more or less) glimpse landscapes (more or less) beyond their own tunnel vision (more or less).

        Those insights are fleeting and hard to remember because of perception’s affinity to seize upon the forward looking focus. Context is intended to be assumed ignored and eventually forgotten.

        ——————
        P.S. I project my own experience and sensibilities. That too is ubiquitous. Everyone does it.

        The advantage of ‘raving’ is to discover beyond, before and about what was previously imagined to be so.

        Those who don’t rave give indications of being not so aware beyond the narrow confines of their specific interests. This may or may not be misleading?

        ———————-

        Excuse me while I go and write a thesis that unifies ‘subjective’ and ‘objective’ reality. This piece of construction is thousands of years overdue.

        Arguing and moving between ‘subjective’ and ‘objective’ experience without overtly understanding the tangible connection between these two variants of experience only serves to frustrate and confuse.

        I know with confidence how to move beyond this persistent fundamental hurdle, Now I must make the effort to gather and disseminate a synthesis.

        Repeating: Everyone builds tunnels. It’s inescapable. That’s what ‘subjectivity’ means.

        ‘Objectivity’ is a recognizable and specific type of ‘subjectivity’ which co-exists within a much larger set of possibilities. That is something which is very difficult to appreciate. By it’s essential nature ‘objectivity’ provides the illusion of universal application.

        It’s not like ‘rocket science’ hunter. I’m a boring limited and ordinary person.

        Rather, it’s about perception. It’s about how many many individual perceptions are formed, used and coupled in an aggregate body called cognition.

        Some see philosophy as a topic that is turgid and agonizingly slow to develop.

        For me, cognitive science has not gotten started notwithstanding the furious efforts made by many to develop it fully.

        The topic of ‘perception’ is almost wholly non-existent despite being accessible and familiar to everyone. Perhaps perception is a process which is far too quick to assume and use, dissolving away into implicit context.

        ‘Perception’ underlays ‘cognition’, ‘philosophy’ and ‘description’. The topic is void.

        I hope my explanation is sufficient here. Thank you for responding.

      • But the tunnel we are in and discussing is the tunnel of global climate disruption caused by CO2.
        Thank you for your survey of tunnels, but please try to be a bit more responsive.
        Defending the dead end tunnel the AGW community has dragged us into by way of an excursion into phenomenological existentialism is not talking about the failure of climate science to control its urge to save the world from a problem it has discovered and cured all in one push…..after we toss a few tens of billion$ there way, of course.
        So care to rewind this and actually answer the point?

      • What we know with confidence [*snigger*]

        So care to rewind this and actually answer the point?

        No.

        Rather I’ll comment on what you describe below …

        But the tunnel we are in and discussing is the tunnel of global climate disruption caused by CO2. …
        …..after we toss a few tens of billion$ there way, of course.

        Tunnel dwellers are known to expand and improve their residence with the aid of a self-consistent, self-similar tool called the ‘inflationary bubble’

        For more information about ‘mortgage derivatives’ and how to inflate your way to ‘fiscal independence and financial wealth consult your with your bank manager or investment broker.

        _________________________________________

        Further background information:
        South Sea Company

        Bounded rationality
        See also

        * Altruism
        * Analysis paralysis
        * Austrian economics
        * Behavioral economics
        * Cognitive bias
        * Homo economicus
        * Irrationality
        * Neoclassical economics
        * Psychohistory
        * Rational choice theory
        * Rationality
        * Rationality and power
        * Parametric determinism
        * Rational ignorance
        * Satisficing
        * Herbert Simon
        * Carnegie School
        * Utility maximization problem
        * Transaction cost
        * Subjective theory of value

        Economic bubble

        An economic bubble (sometimes referred to as a speculative bubble, a market bubble, a price bubble, a financial bubble, a speculative mania or a balloon) is “trade in high volumes at prices that are considerably at variance with intrinsic values”.[1][2] It could also be described as a trade in products or assets with inflated values.

        While some economists deny that bubbles occur,[3] the cause of bubbles remains a challenge to those who are convinced that asset prices often deviate strongly from intrinsic values.

        While many explanations have been suggested, it has been recently shown that bubbles appear even without uncertainty,[4] speculation,[5] or bounded rationality.[6] It has also been suggested that bubbles might ultimately be caused by processes of price coordination[7] or emerging social norms.[6] Because it is often difficult to observe intrinsic values in real-life markets, bubbles are often conclusively identified only in retrospect, when a sudden drop in prices appears. Such a drop is known as a crash or a bubble burst. Both the boom and the bust phases of the bubble are examples of a positive feedback mechanism, in contrast to the negative feedback mechanism that determines the equilibrium price under normal market circumstances. Prices in an economic bubble can fluctuate erratically, and become impossible to predict from supply and demand alone.

  64. Dr Michael Cejnar

    @JCH
    Sorry, I did not intend to misquote anyone and I certainly did not suggest anyone was being offensive. I am however frustrated by a lack of answer to the key objections raised by sceptics, which appeared dismissed by Chris by a referal of reader to basic textbooks. I know the answers are not there, having read some, e.g. text by McGuffie. Perhaps the scientists here don’t know, perhaps the questions are seen as stupid to them, perhaps they are tired of answering them, (though they are not tired of alarming people) – but they won’t win the public by dismissing them.

    Regarding your father practicing medicine for 50 years and never allowing a patient to have a say in anything…..yes, those were the good old days. But is that how establishment Climate Scientists see their relationship with dissenting colleagues and the public? :)

    • Doc, my dad was veterinarian.

    • Dr. Michael, please bare with a slightly long rant that doesn’t amount to saying much for a second:

      In general, I think you’ll find a lot of people are very willing to answer questions. I know I am, and I’ve done so on this board repeatedly.

      Several years ago, I emailed an expert about a question, which in retrospect would have been better answered by opening up a textbook on thermodynamics. A textbook may not have actually answered my question explicitly, but again in retrospect, I realized it wasn’t a very good question. The fact I couldn’t recognize that it wasn’t a good question promoted some initial anger at the response, but looking back I also see that if he answered my specific question it wouldn’t have actually allowed me to learn anything about the topic. Learning what’s right is a great first step, as opposed to learning what is wrong about 50 different items on a list.

      That said, it is very much appreciated if people who have legitimate questions phrase them as questions rather than bold assertions. I, for example, don’t know a thing about black holes. If I approach an astrophysicist with a thought I am unclear about, I can either ask him a question or I can tell him he’s a liar and we really don’t know anything about black holes because they are complex systems and there’s no evidence for anything. You can pick which one of those is the better approach.

      Now, it may seem arrogant, and it may seem dismissive, but when a teacher receives a question that reflects legitimate curiosity, yet also reflects unfamiliarity with the “basic” stuff, then that person may recommend that the person look up some literature/textbooks first. It’s very difficult to teach calculus if your student doesn’t know algebra and trigonometry first, and that’s why schooling has pre-requisites. The system isn’t in place to dismiss people who don’t know algebra, and there’s classes for them too. Usually students at this level aren’t bold enough to stand up and declare that the whole field of mathematics is crap :-)

      You might not like that approach, and in other settings (blog debates) it may be difficult to sort out which types of questions are akin to the student sitting in the calculus class without algebra background, but experts, professors, or even people studying out of interest for several years can recognize it, and pointing out references elsewhere is not dismissive…it’s setting the student along the right path. RobB expressed himself as a serious student of the subject, and to the extent I didn’t misread his intentions, I think someone with unfamiliarity with the basics shouldn’t start off reading a boatload of contradictory “technical” information, since they are not apt to make a judgment on the matter for good reasons, but rather for things like who talked better or who got the last word in.

      Now I’ll make a claim you may not like: In the textbook examples I provide, anyone who reads these books will already start off on better footing than 95% of the people engaging in these blog wars. The books I referenced provides the training equivalent to almost an undergraduate degree in Atmospheric Science, which usually takes some two years of relevant coursework, on top of an initial two years of calculus and physics background. This isn’t arrogance or dismissiveness, it’s how education works. Same with any topic of “internet debate.” The fact is many people become initialized into these debates by watching a youtube video (particularly younger people) and when they became convinced that the video must be right, it becomes difficult to convince them otherwise, regardless of the science.

      This training might not equip them with the tools to respond to every skeptical argument out there, but hopefully it will set a person on the right ground to recognize how to think good about a topic and will weed out the more obvious absurdities… such as recognizing why “the greenhouse effect violates thermodynamics” is simply not even a legitimate scientific issue.

      That’s all…

      • Chris,
        If the astrophysicist was demanding many many billions$ and claiming that the world would end if he did not get that money, while then being shown in his own words to be fluffing the books and over stating the risk ‘to be more clear’, then yes, I would have every right to point that out to him.
        The great plebe masses may not understand physics any better than they understand theology, but they do understand bs when they see it. Even if dressed up as science.

      • Chris,
        I appreciate your perspective. Coming from a long line of scientists and educators I recognize the standard approach: “Go complete the prerequisite coursework and then we can get down to a serious discussion.”
        This works very well within the academic world. It is a waste of time to teach gravitational physics to someone who cannot perform basic calculus. If the only consequence is whether a student gets accepted to grad school this approach would be efficient and effective. It isn’t.

        The concept of AGW and it’s policy implications suggest a radical change in the way we all live, and trillions of dollars to reinvent ourselves and move away from fossil fuel energy sources. This is a very tough sell. If we are to proceed we must sell this not only to academics but to government representatives, businessmen, florists, auto mechanics and janitors to name a few. For such a radical policy change to work, everyone must buy in.

        Suggesting that people around the world give up the cars, stoves, and heaters they have used all their lives will raise a lot of questions. I am not sure how to best answer these questions but I know that “read these four textbooks and get back to me” will generate a tremendous amount of resistance to anything else I have to say.

  65. Michael Larkin

    Chris Colose,

    I can understand to some extent where you are coming from. I don’t have expertise in climate science, but I do have it in other areas, at least in relation to some people. And surely, there comes a point at which one can’t explain certain things with fidelity unless the listener has a minimum level of competence.

    The thing is, I have genuinely tried to understand some of the detailed science, but I can’t get past first base because I don’t have that minimum level of competence. My principal shortcomings are in maths and physics. Some people, and I am one, don’t have much of a head for maths – I got as far as elementary calculus and knew I couldn’t go any further. I was always more interested in biology. There’s little wrong with my abilities to think logically – I earned my living for many years in commercial software development – and I can spot errors in logic pretty quickly – but I need to understand the detailed grounds of an argument, which doesn’t apply here.

    What chagrins is that you seem to be saying that there’s no hope for me and people like me to come to understand enough of climate science to be able to judge whether it’s sound or not. Either we somehow do the impossible and get up to speed, or we accept what scientists say.

    Thing is, some climate scientists whom I have no less reason to respect than the consensualists are sceptics. I would quote Roy Spencer. He has an article entitled “My Global Warming Skepticism, for Dummies” here:

    http://www.drroyspencer.com/2010/07/my-global-warming-skepticism-for-dummies/

    Being one such dummy, this looks reasonably persuasive, though I’ll grant you it may be wrong. Even Dr. Spencer concedes he may be wrong; he’s in a minority, knows it, but isn’t conceding defeat. Why should he if he thinks he is probably right? And yes, why should you if you also think you are probably right? I don’t expect that of you or anyone else.

    But please realise, this issue is too important for me and everyone else on the planet to make an arbitrary decision one way or the other. And I’m not going to let a claim of mere superiority of adherents to one particular view to sway me. Dr. Spencer has something cogent to say on that issue in his point 17:

    “How Important Is “Scientific Consensus” in Climate Research?

    “In the case of global warming, it is nearly worthless. The climate system is so complex that the vast majority of climate scientists — usually experts in variety of specialized fields — assume there are more knowledgeable scientists, and they are just supporting the opinions of their colleagues. And among that small group of most knowledgeable experts, there is a considerable element of groupthink, herd mentality, peer pressure, political pressure, support of certain energy policies, and desire to Save the Earth – whether it needs to be saved or not.”

    We seem to have an irresolvable impasse here. You’re telling probably the large majority of humanity that they can’t hope to understand what you understand, and yet we’re being encouraged (I’m not saying by you personally) to spend enormous amounts on a problem that might not even exist, or if it does, be of much significance. Many of us can’t bring ourselves to support that precisely because we don’t understand the science and because there is obvious difference of opinion even amongst experts. Roy Spencer isn’t alone, of course, and even though our host is an AGW supporter, she’s recognising more uncertainty than is generally admitted to in that camp.

    If you thought you were helping ease the issue, you aren’t. You’re actually making it worse. You’re telling me there’s no point asking questions because I can never get detailed enough answers to make a sensible choice.

    Given that this circumstance applies, imagine yourself in my position; that others are expert in something you’re not and know you never will be, but that it is vital you make the right decision based on their advice before committing resources. Advice which markedly differs. Tell me, which would be the most logical choice:

    1. Accept the opinion of the majority
    2. Accept the opinion of the minority
    3. Suspend judgement and hope that in due course some definitive evidence will create unanimity

    Seriously, don’t couch this in terms of climate science. Try to think of something completely different.

    • Michael, I actually understand where you are coming from. The problem is with the overall AGW argument, the way it is structured. It comes across to people outside the field as a pile of circumstantial evidence, with confidence levels in conclusions from this evidence assigned by experts. Then people take potshots at pieces of the evidence, and then the experts don’t look so trustworthy after climategate. And then serious and well educated people trying to understand this are told they need to have some special competence to understand this. This isn’t rocket science, but its a very complex system (that the scientists have arguably oversimplified). And if this doesn’t add up for people with college degrees who have taken a course in calculus and some science courses that have tried to investigate the issue, then the problem is with the scientists trying to make the overall case. Yes there are thousands of good journal articles out there on pieces of the subject. The problem is when you try to integrate everything and make a case, given the complexity of the climate system. Then using this to drive a massive treaty on global energy policy, and scientists are wondering why the support is lacking.

      • Dr. Curry,
        I would propose a thought experiment regarding your clearly written response to Michael:
        What if the problem is not that the climate scientists (CS) have poorly communicated as you assert? What if the real mis-communication has been in the communications internally? What if the communication has resulted in the CS community building an unwarranted level of confidence in its own work product?
        I would suggest that is closer to the logical conclusion of finding out that so many outside the CS community see big problems in the community position.

      • Michael Larkin

        Thank you for your respone, Dr. Curry, and for the empathy.

        Am I to be encouraged? Can I in fact understand this to mean that I CAN understand climate science if only I can find some way to bring all the complexity together, or if some genius in communication can do what Chris Colose (Is he a PhD? If so I ought to be using his title, but no offence intended) says he can’t, then that is what the world is waiting for. But it would need to come from a completely disinterested source.

        I feel like Diogenes with his famous lantern…

      • Dr Curry, I’m not sure that “potshots” is an appropriate term. As an example take stratospheric cooling. From 1979 to 1994 the stratosphere was cooling. It has not been cooling since then and the trends are equal in length. This does not conform to the models and probably deserves a more worthy designation such as barrage, especially considering how often the stratospheric cooling is cited as evidence in arguments. On the other hand this doesn’t flow well in the paragraph so I can see where potshots may have been the word of choice despite it being what I would consider an understatement of the facts.

      • Agreed that there is some serious criticism of the AGW argument; my statement was in the context of how this seems to be perceived by the public.

      • I think how it is perceived by the public largely rises and falls with weather, not potshots or gates.

        If it gets hotter, sell denial; if it gets colder, sell science. Scandals blow over. They have a short shelf life.

      • Stone a bleedin’ crow! People are clueless about ‘subjective’ point of view. You are a giant amongst midgets and can do a better job of expressing yourself

        I follow what you assert and I appreciate why you are saying it. From personal experience, it’s evident that many won’t be able to track you. You make the same mistake that I do. You alter the implied context too rapidly. Most people find it very difficult to detect and follow that “shifting contextual landscape”.

        First off you come across as *appearing* to be slamming your own colleagues (You are actually slamming the public because you are assuming that the public (as yourself) are cognizant of all the unstated assumptions internal to the AGW evaluation activity). …

        Michael, I actually understand where you are coming from. The problem is with the overall AGW argument, the way it is structured. It comes across to people outside the field as a pile of circumstantial evidence, with confidence levels in conclusions from this evidence assigned by experts. Then people take potshots at pieces of the evidence, and then the experts don’t look so trustworthy after climategate.

        1) – “The problem is with the overall AGW argument, the way it is structured” [Inference: you are alluding to the IPCC]

        2) – “It comes across to people outside the field as a pile of circumstantial evidence” [Inference: the process involves aggregating and integrating individual observations]

        3) – “with confidence levels in conclusions from this evidence assigned by experts.” [Inference: per each individual observation there is indication of it’s quality (reliability)

        4) – “Then people take potshots at pieces of the evidence.” [Inference: People respond/react to each solitary packet of information that is tossed at them and appear to be heedless of otherwise]

        5) – “and then the experts don’t look so trustworthy after climategate. ” [Inference: a few experts are outed to be ordinary mortals enthusiastically engrossed in academic gamesmanship]

        You have mentioned 5 things. At each step of the progression from 1) through 5) the scale of focus and the implied context are altered.

        Most people have difficulty cluing into context at the outset. Tracking that implied context as it changes scale while roaming across a shifting landscapes in real time demands all the more ability.

        No problem here from me. I do it very easily.

        I’m your expert! The reason I am competent with it is because it’s more or less the only thing I do. It’s that or nothing.

        Other people have their own individual. Chances are, it’s likely to be the ability to track shifting context. YMMV.

        Now you do what appears to be the infamous Curry about face.

        Suddenly you give the appearance changing sides. You provide the the appearance of slamming the public. It’s the public that’s misconstruing the ‘implications’ of the serious criticism. ….

        Agreed that there is some serious criticism of the AGW argument; my statement was in the context of how this seems to be perceived by the public.

        .. Unfortunately in this instance you are slamming both yourself and your colleagues,probably without realizing it.

        Much of the confusion in communicating the situation about AGW stems from not overtly stating the inherent unspoken background context.

        _________________________________

        Since the experts seem to be clueless regarding what they assume but fail to declare, I guess that I shall have to it for them. yuck :-(

      • Steven – stratospheric temperature is affected by a multitude of factors including volcanic eruptions, CO2, and ozone. If ozone increases (e.g., due to the Montreal Protocol banning CFCs), the stratosphere should warm unless it is also subjected to a cooling influence. Despite interannual variations, the long term trends continue to be consistent with a combined influence of ozone and CO2 as expected. This expectation is based on fundamental principles of physics and does not originate in the models, which merely quantify it.

      • Yes, I’m aware there are other factors involved.

        Ozone and temperature trends in the upper stratosphere at five stations of the Network for the Detection of Atmospheric Composition Change

        W. Steinbrechta et al

        International Journal of Remote Sensing, Volume 30, Issue 15 & 16 2009

      • No, the long term trend is not consistant.

      • A rigorous analysis of the multiple factors affecting stratospheric temperature trends is given by Ramaswamy et al – Anthropogenic and Natural Influences in the Evolution of Lower Stratospheric Cooling, Science 311,1138,2006

        Figure 2 deconstructs the various factor, demonstrating the respective roles of ozone depletion, increases in CO2 and other greenhouse gases, and volcanic eruptions, all of which play some part. This analysis showing consistency with observational data is based on modeling, but the cooling effect of CO2 is derivable from basic radiative transfer principles without recourse to models.

      • Fred, explaining to me how things happen does not explain away that they aren’t happening as modeled. Perhaps you should explain it to the authors of the paper I cited :

        W. Steinbrechta; H. Claudea; F. Schnenborna; I. S. McDermidb; T. Leblancb; S. Godin-Beekmannc; P. Keckhutc; A. Hauchecornec; J. A. E. Van Gijseld; D. P. J. Swartd; G. E. Bodekere; A. Parrishf; I. S. Boydf; N. Kmpferg; K. Hockeg; R. S. Stolarskih; S. M. Frithh; L. W. Thomasoni; E. E. Remsbergj; C. Von Savignyk; A. Rozanovk; J. P. Burrowsk

        who state this:

        “This non-decline of upper stratospheric temperatures is a significant change from the more or less linear cooling of the upper stratosphere up until the mid-1990s, reported in previous trend assessments. It is also at odds with the almost linear 1 K per decade cooling simulated over the entire 1979-2010 period by chemistry-climate models (CCMs). The same CCM simulations, however, track the historical ozone anomalies quite well, including the change of ozone tendency in the late 1990s. “

      • Chemistry climate models are appropriate for ozone depletion but not for the cooling mediated by CO2. If you look at ozone levels post-1994, they rise slightly. The flat temperature is inconsistent with effects dictated exclusively by ozone, but consistent with the combined effects of ozone and CO2. I’m not sure why the authors you cite neglected this – perhaps they were simply trying to consider the ozone-temperature relationship exclusive of other variables.

      • The results already showed insufficient cooling, and you are guessing that they left out an element of the equation that should have caused even more cooling therefore making the discrepancy even worse. I’m not sure how that improves the situation. Of course it makes no sense to say you expect to find a -1K trend if all you are taking into account is increasing ozone, does it?

      • -1K/decade trend. I don’t bother going back after I have made a typo since I would be going back entirely too often. I really should learn to be more careful but that post comment button is so tempting.

      • I regret that the link I supplied to the Science article will put some readers behind a paywall, because the article thoroughly analyzes the multiple factors involved in altering stratospheric temperature – CO2, ozone, volcanism, solar irradiance, etc., – and demonstrates a role for each. It also makes clear that individual factors affect temperature differently at different altitudes. Note that warming due to rising ozone and cooling due to rising CO2 can cancel out at certain altitudes, leaving a flat temperature line at those altitudes despite the observed rise in ozone.

        In any case, when two different papers present different conclusions, the best recourse for readers is to read both papers rather than follow second-hand discussions here. They can then make their own judgments.

      • Fred, if you have access to the paper you are using to support your position then by all means feel free to post the pertinent parts here. I don’t think many of the people reading our conversation will be confused by what ozone and volcanoes do to the temperature in the stratosphere so I doubt an explanation of that is in order. The argument that the lack of cooling is accounted for might be interesting to many readers. I know it would be to me.

      • I haven’t been able to look at the Steinbrechta stuff yet, and won’t have time for at least a week or so, but one of the more up-to-date papers on this (at least that I’m aware of, I only track this stuff loosely) is http://arlsun.arlhq.noaa.gov/documents/JournalPDFs/RandelEtal.JGR2009.pdf

      • Chris, it is an interesting paper but the purpose seems to be establishing sources of error from measurement techniques. It doesn’t appear to change the data used or attribute the causes of the recent lack of cooling. In other words, it doesn’t dispute anything in the paper I referenced as far as I could tell. I’ll be looking foward to your evaluation of the Steinbrechta paper.

      • And then serious and well educated people trying to understand this are told they need to have some special competence to understand this. This isn’t rocket science, but its a very complex system (that the scientists have arguably oversimplified).

        If it’s a very complex system then why is it unreasonable to suppose that some special competence is required to properly understand it? Even for serious and well educated people. I don’t pretend to be anything other than a layman myself and I try to be aware of the limitations of my knowledge, I think it’s a principle which is best followed by everyone, whatever their qualifications.

        And if this doesn’t add up for people with college degrees who have taken a course in calculus and some science courses that have tried to investigate the issue, then the problem is with the scientists trying to make the overall case.

        Why is this neccessarily true? Why do you always put the blame entirely on the scientists and assume absolute good faith and willingness to approach the subject without any preconceptions on the part of the skepticss?

      • Why do you believe that people who ‘get’ evolution, modern cosmology, quantum physics, Newton, etc. should not be qualified to point out that climate science is full of bs and hot air?

      • Well, by “get” I presume you mean are able to understand the basic principles which underly the subject and some of the mechanisms involved.
        That’s different from being qualified to overturn the current scientific understanding of the subject. There are certainly people who are well educated and intelligent who claim to be able to show that evolution is wrong based on arguments of irreducable complexity and the like.

      • Hi Andrew

        The two examples are not comparable.

        You do not need to be an expert in all aspects of climate modelling to know that a model or set of models that has yet to make a single prediction verifiable by experiment – after 30 years of endeavour – is pretty much equivalent to crap.

        You do not need to be an expert in the details of climate data collection and analysis to know that any system that cannot consistently and correctly identify and archive the origin of the data that it has got is very unlikely to be a reliable source for all future predictions (nor for training the models).

        You do not need to be very clever to work out that there is huge potential for ‘human error’ in the data adjustment process. And even more when those adjustments are undocumented and the raw data thrown away.

        and so on and so on…

        Your argument would be correct if a whole lot of sceptics were saying – ‘your science is wrong..here is mine – it is better’.

        But we’re not. We’re saying that the Emperor of AGW is ‘very poorly and scantily clad’. We are not in the business of designing his new wardrobe.

        That is the job of the climatologists, if and when they acknowledge the legitimate criticisms presented. Do not mistake the one for the other.

      • Hi Latimer,

        OK, I understand the distinction you are making and it’s a fair one. But there is a difference between making legitimate criticisms and making wild and sweeping generalisations. To answer your specific points –

        You do not need to be an expert in all aspects of climate modelling to know that a model or set of models that has yet to make a single prediction verifiable by experiment – after 30 years of endeavour – is pretty much equivalent to crap.

        Models are not perfect but neither are they as useless as you say. If they were then scientists would not use them. Among other things, models have correctly forecast that warming from GHG emissions would result in more warming at the poles than at the equator and more warming at night than during the day, and tropospheric warming/stratospheric cooling. They accurately predicted the effects of the Mt Pinatubo eruption and when Spencer’s satellite data initially contradicted the models it was the models which were proved right. I’m sure at those more knowledgeable than me can give more examples.

        You do not need to be an expert in the details of climate data collection and analysis to know that any system that cannot consistently and correctly identify and archive the origin of the data that it has got is very unlikely to be a reliable source for all future predictions (nor for training the models).

        Phil Jones’s data archiving certainly left a lot to be desired, although the original data is still held by the various national meteorological associations who provided it to CRU. But do you have any evidence that there is a more widespread problem?

        You do not need to be very clever to work out that there is huge potential for ‘human error’ in the data adjustment process. And even more when those adjustments are undocumented and the raw data thrown away.

        Yet there is still good agreement between the GISTEMP and Had/CRUT temperature records and the satellite data which would indicate that there is no great problem. Also, there are some people doing independent analysis of the data and they haven’t found any big problems either – see http://www.skepticalscience.com/Assessing-global-surface-temperature-reconstructions.html.

        That is the job of the climatologists, if and when they acknowledge the legitimate criticisms presented. Do not mistake the one for the other.

        Of course climate scientists should acknowlege legitimate criticisms and like most people can occasionally be overly defensive when criticised. But for example CRU has accepted that it needs to overhaul its procedures for data handling and responding to freedom of information requests, and make its data as widely available as possible. I read some pretty scathing criticisms of the IPCC from climate scientists over the Himalayan glacier fiasco, and the IPCC itself is reviewing its procedures in the light of this and other criticisms.

        But equally scientists are perfectly entitled to defend themselves if they feel that criticisms are not legitimate or are overstated and point out to skeptics if they are mistaken. And those making criticisms shoud be careful to keep them in proportion and not assume the worst possible motives on teh part of scientists if tehy want to get a fair and reasonable response

    • Michael Larkin,

      Yes, from the class of individuals within academic science we occasionally run across those with a condescending attitudes toward those outside their narrow academic discipline or toward those outside of academia/science per se. Yet, I see others, the very best of the best scientists, ‘bending over backwards***’ to keep their papers and their discussions crystal clear and open. We need to strongly reward/encourage the later publically. The former will ‘get the memo’ eventually.

      *** Apologies to Feynman

      Cheer up! : )

      John

      • Arrogant, snotty twerps can be just as right as people who bend over backwards to be sweeties.

        Reward right.

      • JCH | November 16, 2010 at 9:47 am

        Arrogant, snotty twerps can be just as right as people who bend over backwards to be sweeties.

        Reward right.

        —————-

        JCH,

        Looks to me like condescending attitude, besides being insulting, just limits communications; harder to tell if someone is ‘right’ with any limited communication scenario. There is a reason when someone acts in a condescending manner; compensation for weakness perhaps.

        John

      • And it is just as likely the friendly, smiling, whatever-it-takes, “I enjoy a beer just like you,” guy is compensating for a reason.

        Reward right; ignore personalities.

  66. Dr Michael Cejnar

    @ JCH – OK, fell for that one. I thought it was toungue in cheek but the opportunity for a dig was too tempting.
    @Chris, no climate scientist spans all climate fields, so communication across fields to othr scientists, including ones like me is always required. But lets just agree to disagree. Ultimately, I want nothing from climate scientists or the green industry – they want something from me – my tax money, and it falls upon them to convince me.

    • I don’t know about what “they” want, Michael, but as a scientist knowledgeable about climate change, I can only speak for myself. I want your children to have a better life.

      • Then spend your own money on it and stop demanding I spend mine to fund your job security.

      • Dr Michael Cejnar

        @Fred Moolten
        Save my children? Fred, I do recognise your personal good intention. But therein lies the problem – the Messiah complex of the movement and the precautionary principle – any risk-benefit irrationality can be justified by crying ‘but think of the children’.

        Fred, equally, I want your children to be not brainwashed (as I was under communists) and not be enslaved in an ‘ecofascist’ world built on a lie, and please look around – there is a lot more real evidence of rising state control and attacks on our freedoms right now than there is of climate catastrophe, vis. UN world governance treaties, Greens wanting suspension of democracy, branding deniers as traitors, carbon credit cards, smart meters controlling our home power, 1010 blowing up non-believers, Wespac bank now refusing to fund ‘gassy’ projects, taxes, carbon permits … there is no end to this. I too feel a moral imperative to save your children from this.

        If you really, really believe the world is being destroyed and no one is listening, then you probably have a moral imperative to make people do the right thing for their own good – for their children, by whatever means – dictatorship, interment, re-education camps – it’s better than destruction of the planet and death of billions, right? Is this not the logical end point of you trying to save my children in the face of catastrophic AGW? I think it’s a moral dilemma that each Alarmists must resolve. How strong is his belief in AGW and how far will it make him go.

  67. Heikki Hartela

    A really interesting discussion here, although I only got to about 100 so far… This is some kind of “runaway greenhouse effect discussion”. I feel guilty adding to the thread.
    I would like to go back to the original post, and ask those of you who were doing climate science at the time of the firs IPCC report: What has changed? Are we more or less certain now?

    A lot of the science appears to be revolving around the “models” (as they may be the best tool we have), and then trying to define how sensible the climate system is from these models. As mentioned the results are also of the same magnitude as natural climate variability. So, in order to get any certainty from the “models” one would have to be able to eliminate the natural climate variability from the calculations.
    -Are we now any closer to understanding the natural variability of the climate, than we were twenty years ago?

    Twenty years ago the water vapor feedback was considered as being positive, with certainty. Reading the discussions that now appears to have gone to the “reason to believe” category.
    -Was the approach to water vapor feedback too simplified back then?

  68. David L. Hagen

    Demetris Koutsoyiannis points out that we KNOW that classical statistics does NOT match climate. Hurst-Kolmogorov Statistics are required.

    Classical Statistics is inconsistent with real-world climate; rather, it corresponds to a static climate
    * Hurst-Kolmogorov Statistics is the key to perceive a multi-scale
    changing climate and model the implied uncertainty and risk
    * Hurst-Kolmogorov Statistics has marked differences from Classical
    Statistics, which are often missed; thus, it implies:
    **Dramatically higher uncertainty of statistical parameters of location
    **High negative bias of statistical parameters of dispersion and
    dependence
    **Dramatically higher predictive uncertainty

    Memory in climate and things not to be forgotten
    11th International Meeting on Statistical Climatology,
    Session 10: Long Term Memory, University of Edinburgh, Scotland, 12-16 July, 2010
    Similarly:

    Only a portion (36% to 46%) of natural variance can be described by orbital forcing. . . .
    The residual time series can be described by an HK process. This is NOT white noise. . . .
    The comparison of statistical analysis between CS (classical statistics) and HK (Hurst Kolgomorov Statistics) results in serious differences in the estimation of data variability.

    Orbital Climate Theory and Hurst-Kolgomorov dynamics

  69. This nonsense about not “communicating well enough…” is, well, nonsense. It is extremely arrogant and elitist. It’s the same stupid arrogant idea that our socialists inside the Beltway (who have no clue about the real world) are trying to push right now after an election which should have put them in their place . “If only we were able to explain our complicated Obamacare system to you (stupid) people, you would love it.” Does ANYONE really believe this pap? Same with climate. Everyone I know is laughing about such statements.

    The majority of people who can read don’t believe in AGW and “disasterous climate disruption,” not because the climate scientists have not explained it well enough, not because it is “too complicated for the (stupid) people,” and not even because the science is equivocal, but BECAUSE the “stupid people” are smart enough to recognize a con, which is continually being affirmed by the really stupid climate science community, politicians, and NGOs, when they attempt to tie EVERY NEGATIVE THING IMAGINATIVE to “global warming.” Now, they are even trying to blame the cold weather on global warming!!!! They are their own worst enemies! It’s a pathetic comedy!!!

    • jae,
      Well said.
      Steve Martin used to have a great joke about how stupid the French are, pointing out that no matter how loudly slowly and carefully he would speak, the idiot French taxicab driver would still not understand what he was saying.
      Climate scientists are convinced we are stupid because we are not believing them, no matter how loudly or histrionically they speak down to us.
      My question up thread was for Dr. Curry to take a different look at her communications concern, and apply it to her own community:
      What if the communication problem is that the AGW community has mis-communicated to itself the quality of the data, the significance of the issue and the implications of the work they are doing?
      No matter how the AGW community dresses this up, if they are the problem, yelling at us more/communicating better does not make them less wrong.

    • More to your point, when the people are bombarded daily with THIS:

      http://www.numberwatch.co.uk/warmlist.htm

      … it becomes almost impossible to NOT be a skeptic, because it seems like the message “we’re all gonna die! run for the hills!” is being heard and retransmitted loud and clear.

      DR CHRIS COLOSE, DR FRED MOULTON

      The journalists are hearing every word you utter, filtering this through environmental activists (sometimes) or climate advocates who are worried about our children (usually) and the numberwatch list is the result. It looks absurd, doesn’t it?

  70. Forgot to include this link in my rant: http://www.numberwatch.co.uk/warmlist.htm

  71. Fred Moolten,
    There is one factor that supporters of the IPCC have not fully taken into account and that is the influence of extreme long-term changes in the solar/lunar tides and their effect on climate sub-systems.

    I will be publishing a paper about this important factor in 2011, so I can only speak in generalities at this point. All will say is that I now have iron-clad scientific proof that extreme lunar/solar tides play a critical role in influencing the world’s mean temperature. The IPCC has not factor this effect into their models and so what you and others have said about the predictions of the Climate models will have to be modified to take into account these important effects.

    • That is quite interesting. It stands to reason that tidal forces will affect climate, particularly via their effects on ocean currents and vertical displacement of ocean water. There is some previous literature on this, I believe, including a paper by Charles Keeling. What will be worth knowing is both the magnitude of the effects, as well as their periodicity. How does the latter relate to known internal climate variations affecting the oceans on a periodic or quasi-periodic basis – ENSO, PDO, AMO, etc.? Is it an independent source of variation or more a contributor to the known variations?

      What journal will your paper appear in?

  72. Fred Moolten:

    From the above, I gather that you haven’t yet been dissuaded from your earlier-expressed views that CO2-mediated warming violates the Second Law of Thermodynamics. I won’t try further.

    Good idea it never does to misrepresent people. You might be accused of mounting a straw man argument a common way to deal with an argument one can’t refute.

    and your views aren’t going to change.

    They will Ferenc has succeeded in helping me change my views some but it’s good that you recognise that you are not up to it, or do you really think that claiming that 4 analysis of the same thing that don’t agree with one another must all be right, is persuasive?

  73. I agree with Hunter about inversion of “communication problem”. However, it might be impossible to overcome the barrier of arrogance of so-called “scientists” of AGW. Their deep ignorance in physics and mechanics of air and complete detachment from reality does not allow any communication. Just look at the standard AGW nonsense and dogmas that are lectured here by Chris Colose with insulting condescension. I cannot find a single statement from him that is not deeply flawed. Here are few examples:

    “The global energy balance of the planet provides an immensely powerful boundary condition that constrains the global climate”

    “This is because the optical depth τ … increases, resulting in the whole planet radiating less energy to space (since the vertical temperature gradient of the atmosphere results in absorption line features).”

    “Armed with knowledge about what appears to be a generally stable climate without forcing (a feature also seen in models)…”

    “The so-called “radiative forcing” provided by the well-mixed greenhouse gases is relatively easy to calculate, and good agreement exists between detailed line by line radiative transfer codes and GCM’s. ”

    The whole situation is very disturbing. Given the green agenda and overwhelming financial support, this field will attract more and more under-educated and unscrupulous freshmen who, fueled by righteousness of goals (save the Earth, save our children) and pressure of job insecurity, would produce more and more climate pseudoscience.

  74. Judith:

    This thread asks if there have been any serious challenges to the statements in AR1 or whether we can a pretty much agree on a list of assertions.

    I cited the interesting work of Ferenc Miskolczi as a challenge to the claim that “We are certain of the following: … increases [of GHG’s] will enhance the greenhouse effect, resulting on average in an additional warming of the Earth’s surface. The main greenhouse gas, water vapour, will increase in response to global warming and further enhance it”

    In response to my request for serious replies to this work , I got the usual atttempted slap-downs, references to insubstantial material and told to do my homework (thanks Fred). Oh yes, and the (increasingly customary) flameball from Chris Colose which included this gem: “Not everything needs a “published response.” This isn’t a game of last words.” (Oh yes it does, assuming climatologists want to claim to be applying the scientific method with due process and rigour!)

    My conclusion from this brief encounter is that Miskolczi presenty stands in answer to your question. Certainty in the original AR1 statements has reduced.

  75. Is there general scientific agreement that basing world economic policy on Al Gore’s “documentary” is bad politics, poor politics, and invalid science?

    I know I’d be better able to engage the consensus view when that view collectively repudiates the hype that is “An Inconvenient Truth”.

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