Worst case scenario versus fat tail

by Judith Curry

 If we omit discussion of tail risk, are we really telling the whole truth? 

Kerry Emanuel

This post is motivated by an essay by Kerry Emanuel published at the Climate Change National Forum, entitled Tail Risk vs. Alarmism, which is in part motivated by my previous post AAAS: What we know. Excerpts:

In assessing the event risk component of climate change, we have, I would argue, a strong professional obligation to estimate and portray the entire probability distribution to the best of our ability. This means talking not just about the most probable middle of the distribution, but also the lower probability high-end risk tail, because the outcome function is very high there. 

Do we not have a professional obligation to talk about the whole probability distribution, given the tough consequences at the tail of the distribution? I think we do, in spite of the fact that we open ourselves to the accusation of alarmism and thereby risk reducing our credibility. A case could be made that we should keep quiet about tail risk and preserve our credibility as a hedge against the possibility that someday the ability to speak with credibility will be absolutely critical to avoid disaster. 

Uncertainty monster simplification

In my paper Climate Science and the Uncertainty Monster, I described 5 ways of coping with the monster. Monster Simplification is particularly relevant here:  Monster simplifiers attempt to transform the monster by subjectively quantifying or simplifying the assessment of uncertainty.

The uncertainty monster paper distinguished between statistical uncertainty and scenario uncertainty:

Statistical uncertainty is the aspect of uncertainty that is described in statistical terms. An example of statistical uncertainty is measurement uncertainty, which can be due to sampling error or inaccuracy or imprecision in measurements.

Scenario uncertainty implies that it is not possible to formulate the probability of occurrence of one particular outcome. A scenario is a plausible but unverifiable description of how the system and/or its driving forces may develop over time. Scenarios may be regarded as a range of discrete possibilities with no a priori allocation of likelihood.

Given our uncertainty and ignorance surrounding climate sensitivity, I have discussed the folly of attempting probabilistic estimates of climate sensitivity, and to create a pdf (see this previous post Probabilistic estimates of climate sensitivity).  In my opinion, the most significant point in the IPCC AR5 WG1 report is their acknowledgment that they cannot create a meaningful pdf of climate sensitivity with a central tendency, and hence they only provide ranges with confidence levels (and they avoid identifying a best estimate of 3C as they did in the AR4).   The strategy used in the AR5 is appropriate in context of scenario uncertainty, where they identify some bounds for sensitivity, and present some assessment of likelihood (values less than 1C are extreme unlikely, and values greater than 6C are very unlikely).

So I starkly disagree with this statement by Emanuel:

we have a strong professional obligation to estimate and portray the entire probability distribution to the best of our ability.

In my opinion, we have a strong profession obligation NOT to simply the uncertainty by portraying it as a pdf, when the situation is characterized by substantial uncertainty that is not statistical in nature.  This  issue is discussed in a practical way with regards to climate science in a paper by Risbey and Kandlikar (2007), see especially Table 5:

 

Risbey

 

Climate sensitivity is definitely not characterized by #1, rather it is characterized by #2 or #4.  The lower bound is arguably well defined; the upper bound is not.  The problem at the upper bound is what concerns Emanuel; I am arguing that the way to address this is NOT through considering a fat tail that extends out to infinity of a mythical probability distribution.

Nicholas Taleb’s black swan arguments emphasize the non-computatability of the consequential rare events using scientific methods (owing to the very nature of small probabilities)

What’s the worst case?

I have spent considerable effort in identifying possible/plausible worst case scenarios, black swans and dragon kings:

Identifying possible/plausible worst case scenarios is much more useful in my opinion  than the fat tail approach to identifying possible black swans and dragon kings in the climate system.

The philosophical foundation for thinking about ‘worst case scenarios’ is laid out in the work of Gregor Betz, see especially his paper What‘s the Worst Case? The Methodology of Possibilistic Prediction.  This paper deserves a thread of its own (I regard it as hugely important), but I want to at least introduce the relevant concepts here. Excerpts

Where even probabilistic prediction fails, foreknowledge is (at most) possibilistic in kind; i.e. we know some future events to be possible, and some other events to be impossible.

Gardiner, in defence of the precautionary principle, rightly notes that (i) the application of the precautionary principle demands that a range of realistic possibilities be established, and that (ii) this is required by any principle for decision making under uncertainty whatsoever.

Accepting the limits of probabilistic methods and refusing to make probabilistic forecasts where those limits are exceeded, originates, ultimately, from the virtue of truthfulness, and from the requirements of scientic policy advice in a democratic society.

‘Possibility’, here, means neither logical nor metaphysical possibility, but simply (logical and statistical) consistency with our relevant background knowledge.

A surprise of the rst type occurs if a possibility that had not even been articulated becomes true. Hypothesis articulation is, essentially, the business of avoiding surprises (of this 1st type). There is, however, a second type of surprise that does not simply extend the picture we’ve drawn so far, but rather shakes it. Our scentific knowledge is constantly changing, whereas that change is not cumulative: scientific progress also comprises refuting, correcting, and abandoning previous scientificc results. Now a readjustment of the background knowledge questions the entire former assessment of possibilistic hypotheses.

I take this brief discussion to indicate that the decision deliberation starts to become messy and complicated. It is not clear to me whether there are general principles which can guide rational decisions in such situations at all. This, however, must not serve as an excuse for simplifying the epistemic situation we face! If a policy decision requires a complex normative judgement, then democratically legitimised policy makers have arguably a hard job; it is, nevertheless, their job to balance and weigh the diverse risks of the alternative options. That is not the job of scientic policy advisers who might be tempted to simplify the situation, thereby pre-determining the complex value judgements.

Alarmism

I have written two previous posts that address the idea that uncertainty increases the argument for action

As Betz points out, there is no simple decision rule for dealing with this kind of deep uncertainty.

Alarmism occurs when possible, unverified worst case scenarios are touted as almost certain to occur.  U.S. Secretary of State John Kerry frequently does this, as does Joe Romm (and Rachendra Pachauri).  A recent example from Dana Nuccitelli, John Cook and Stephen Lewandowsky:

The climate change uncertainty monster – more uncertainty means more urgency to tackle global warming

The problems with this kind of thinking is summarized in my two previous posts (cited a few paragraphs above); in summary this is a stark and potentially dangerous oversimplification of how to approach decision making about this complex problem.

Summary

Back to the AAAS statement What We Know.  Unverified hypotheses about fat tail events are NOT what we KNOW.  Presenting this as knowledge rather than speculation, and unduly focusing on it for policy decisions, is alarmist.

My biggest concern is that by unduly (and almost exclusively) focusing on AGW that we are making a type 1 error:  a possibility that has not been articulated might come true.  These possibilities (e.g. abrupt climate change) are associated with natural climate variability, and possibly its interaction with AGW.

Pretending that all this can be characterized by a fat tail derived from estimates of climate sensitivity is highly misleading, in my opinion.

So I agree with Emanuel that we should think about worst cases (e.g. black swans and dragon kings); I disagree with him regarding how this should be approached scientifically and mathematically.  However, undue focus on on unverified worst case scenarios as a strategy for building political will for a particular policy option constitutes undesirable alarmism.

 

383 responses to “Worst case scenario versus fat tail

  1. In the paragraph above table 5: “. . .not to simplify . . . “

    • David L. Hagen

      McKitrick fixed Weitzmal Dismal Theorem Ln Simplification Fat tail
      Much of the “fat tail” doom and gloom is caused by Weitzmal’s Ln(C) simplification error implying an enormous willingness to pay. By deriving the accurate equation, Ross McKitrick eliminates this error and the “pay through the nose” major Fat Tail financial policy alarm.

      The Weitzman Dismal Theorem (DT) states that peoples’ willingness to pay to insure against possible future global warming damages is, effectively, infinitely large, as long as they have constant relative risk aversion and an uninformed prior view about the risks of climate change. . . . I show that the degeneracy is not a general result. It relies on the use of a log approximation to the rate of consumption growth and an extreme prohibition on intergenerational wealth transfers. Use of an exact growth measure simplifies the pricing model such that insurance prices can only be unbounded in a trivial case. In general the model implies unexceptional willingness to pay to avoid future costs, even when climate risks are large and uniformly distributed.

      Ross McKitrick, Cheering Up the Dismal Theorem, Dept. Economics & Finance, Discussion Paper, March 16, 2012, College of Management and Economics, Guelph Ontario (corrected 2013)

  2. Emanuel:

    A case could be made that we should keep quiet about tail risk and preserve our credibility as a hedge against the possibility that someday the ability to speak with credibility will be absolutely critical to avoid disaster.

    Does he mean for climate science or all of science?

  3. Climate science seems to be all about Type 1 errors. The conditions being experience sometimes mirror those that predate the thesis of the effects of man made CO2. So there are a lot of other factors at work. Factors that are getting short shrift due to the alarmism of a trace gas.

  4. Worse-case scenarios call for private-sector retention of resources–wealth- is-health adaptation.

    Government mitigation policy from a fat tail inherently runs into government failure in the quest to address market failure. Kerry Emmanuel still has not made a case for real-world government mitigation, just blackboard optimization for a Climate God to know and implement.

  5. Sorry, Emanuel

  6. The alarmists seem always to ignore the adverse consequences of what they advocate – CO2 emission reduction. But for nuclear, non-CO2 alternatives will increase the cost of energy increasing prices for food, manufactured goods, and likely everything else. They also ignore the favorable consequences of higher CO2 – better crop yields and a slightly warmer and a more uniform, thus less stormy climate. Similarly, they ignore the likelihood that the actions they propose will have little or no effect on climate. Shouting ‘fire’ in a theater because the projector might start one is never a good idea.

    • I don’t think the lower bound for climate sensitivity is as defined as believed, and I don’t find distributions that don’t include negative values credible. It’s not implausible that climate sensitivity is or will become negative. I would think it is at least as likely as it becoming greater than 3C. It’s not implausible that a response to more LW radiation could lead to a decrease incoming shortwave radiation by an even greater amount (so long as the decrease in SW doesn’t decrease the amount of LW).

      The greenhouse effect is diffuse over the surface and through the atmosphere. Warming in one region could produce a unknown albedo effect in another region, resulting in cooling rather than warming overall.

  7. Judy – Excellent post. I only disagree with your statement

    “The lower bound is arguably well defined;”

    I assume you are referring here to the global annual average surface temperature anomaly. If one assumes that the radiative forcing of added CO2 dominates all other radiative forcings and feedbacks, you are, of course, correct.

    However, even natural radiative forcings (e.g. solar, multiple volcanic eruptions, internal long term variations), could result in values of the global annual average surface temperature anomaly below your lower bound. Combined with human negative radiative forcings (e.g. sulfates), the anomaly could even be less than the “lower bound”.

    This high level of uncertainty is why we have proposed the bottom-up assessment of risk in our paper

    Pielke Sr., R.A., R. Wilby, D. Niyogi, F. Hossain, K. Dairaku, J. Adegoke, G. Kallos, T. Seastedt, and K. Suding, 2012: Dealing with complexity and extreme events using a bottom-up, resource-based vulnerability perspective. Extreme Events and Natural Hazards: The Complexity Perspective Geophysical Monograph Series 196 © 2012. American Geophysical Union. All Rights Reserved. 10.1029/2011GM001086. http://pielkeclimatesci.files.wordpress.com/2012/10/r-3651.pdf

    The abstract of our paper reads

    “We discuss the adoption of a bottom-up, resource-based vulnerability approach in evaluating the effect of climate and other environmental and societal threats to societally critical resources. This vulnerability concept requires the determination of the major threats to local and regional water, food, energy, human health, and ecosystem function resources from extreme events including those from climate but also from other social and environmental issues. After these threats are identified for each resource, then the relative risks can be compared with other risks in order to adopt optimal preferred mitigation/adaptation strategies. This is a more inclusive way of assessing risks, including from climate variability and climate change, than using the outcome vulnerability approach adopted by the Intergovernmental Panel on Climate Change (IPCC). A contextual vulnerability assessment using the bottom-up, resource-based framework is a more inclusive approach for policy makers to adopt effective mitigation and adaptation methodologies to deal with the complexity of the spectrum of social and environmental extreme events that will occur in the coming decades as the range of threats are assessed, beyond just the focus on CO2 and a few other greenhouse gases as emphasized in the IPCC assessments.”

    Such an approach permits a more robust response to the global annual average surface temperature over a wide range of values, including what Kerry has written about.

    Roger Sr.

    • That caused me pause also. I think you are right. The lower boundary is not established with any certainty. It’s more likely temperatures will increase than decrease, but how do you quantify that?

      Roger: are you going to publish anything soon at Fivethirtyeight? Just curious . . .

    • Jim Cripwell

      I was about to write a long discourse on this, but, fortunately, Roger has beaten me to it. I would point out our hostess also wrote “values less than 1C are extreme unlikely,”

      Global temperatures have not risen in the 21st century, despite massive increases in the amount of CO2 we have added to the atmosphere.. Global warming has ceased, at least temporarily. No-one has measured a CO2 signal in any modern temperature/time graph. Beenstock et al looked for such a single, and failed to find one.

      I suggest our hostess should not ignore the fact that the lower limit of the bounds of climate sensitivity might be just plain wrong. The lower limit is, IMHO, indistinguishable from zero.

      • Agreed the lower limit might be plain wrong, but given our background knowledge on this, it isn’t unreasonable to say very unlikely below 1C. IMO, 0C is probably a better very unlikely lower limit. But the lower limit is arguably constrained within 1C; the upper limit is not.

    • Roger Sr.: “I assume you are referring here to the global annual average surface temperature anomaly.”
      The AR5 WG1 statement that “values less than 1C are extreme unlikely” concerns the sensitivity of global annual average surface temperature to a CO2 doubling. It was not a projection of the anomaly value itself, which as you say can be affected by other factors such as solar or volcanoes.

    • Jim Cripwell

      Judith, you write “but given our background knowledge on this”

      What background knowledge? The only background knowledge you have is based in hypothetical estimations, and the output of non-validated models.

      The vast majority of empirical data points to the lower limit at 0 C.

    • I don’t think the lower bound for global average temperature sensitivity (GATS) is as defined as believed, and I don’t find distributions that don’t include negative values credible. It’s not implausible that climate sensitivity is or will become negative. I would think it is at least as likely as it being greater than 3C. It’s not implausible that a response to more LW radiation could lead to a decrease incoming shortwave radiation by an even greater amount. This scenario is at least as likely as the ridiculous chain of events required for catastrophic climate responses to downwelling LW radiation.

      The greenhouse effect is diffuse over the surface and through the atmosphere. Warming in one region could produce a unknown albedo effect in another region, resulting in cooling rather than warming overall.

      The transient GATS is likely less than 1.5, the assumptions that it will increase seem rather riduculous to me. And yes, I think it really could go negative, with warming near the poles producing albedo effects in the mid and low latitudes once we reach a certain amount of warming.

    • Dr Curry’s suggests that ‘Climate sensitivity…lower bound is arguably well defined…’. Yes, the lower limit for this elusive quantity is indeed well defined. It is zero. One doesn’t need the ‘arguably’. It must be higher than zero, but nobody knows how much higher, so zero is the limit.

  8. Unfortunately, the total collapse of the Greenland Ice Sheet isn’t in the fat tail.

    It is not a dragon king nor a black swan.

    • When is that suppose to happen? If I remember right National Geographic said it could happen within the next 75 to 200 years. What’s the probability?

    • Let’s see now. How long would it take 3.8W/m2 to melt through a 2-mile thick slab of ice?

    • Fortunately, total collapse of the Greenland Ice sheet is geophysically impossible. The underlying land is bowl shaped, in part because of mountains and in part because of isostaic compression. It would have to melt. Which it presently very slowly is. And a paper two years ago cited in my book calculated that a 3C rise would take up to 40,000 years. “simple” calculation based on volume of ice, current net loss per year, and net annual increase in loss at increasing annual average temperature. Which is why it didn’t come close to disappearing during the Eemian, when Greenland temperatures for several thousand years were 3C higher than at present.we have numerous ice cores to prove it.
      Mr Droege, you could do better than spout utter nonsense.

    • Probability 100%,

      That what Michael, Robert and Richard said on the debate from the previous post.

      How soon? Sooner than the age of a lot of buildings.

      Phatboy, I get 31,000 years for 3.8 w/meters2 to melt through 2 miles of ice.

      But it all doesn’t have to melt to collapse, ever see a glacier calve?

      And how does the TOA energy imbalance rate compare to the rate that Greenland is warming?

      We know from paleo that the ice sheets don’t survive 400 ppm CO2, how we get to the collapse is one of the unknowns.

    • Why isn’t the collapse of the Greenland Ice sheet in the fat tail, dredge? How could they forget to include that?

    • Bob, as Rud pointed out, collapse is a physical impossibility.
      Yes, I have seen glaciers calve, just as I have seen waterfalls falling into the sea
      And the TOA imbalance hasn’t yet reached anywhere near 3.8W/m2, let alone the surface forcing at Greenland.

    • Don, he’s right about it not being in the fat tail, as it’s virtually certain to happen – albeit in tens of thousands of years at the earlest

    • Rud, your Greenland is a bowl is a cracked theory, because it is not. Look at topographical maps of the mountains of Greenland under the ice, and you will find that there are numerous outlets that are near sea-level.

      And during the Eemian, sea-levels were 4 to 6 meters higher than today.
      And those Eemian ice cores found evidence that the surface was melting similar to the events of 2012 when the entire surface of the Greenland Ice sheet was melting.

      But we are on a path to blow by the temperatures of the Eemian interglacial, so nothing is geophysically impossible.

      Rud, stop posting such drivel, and there was a front end loader and a washed out bridge that says it’s not melting slowly, the rate of melt is accelerating.

    • Don, it’s not in the fat tail because it’s square in the middle.

    • bob,
      The level of critical analysis you offer also suggests that Earth becomeing Venus 2.0 is a fat tail risk that must be considered. Also, the rising run away temperatures could start mutating water loving reptiles into godzilla type monsters that could ravage our cities. And since we are uncertain, we should also preapare for AGW caused expansion of the atmosphere to capture large asteroids and send them hurtling to Earth. And as the Greenland icesheet collapses, it could trigger volcanoes in a teleconnected effect that would tset off the Yellowstone super volcano, burying North America under meters of ash.
      Wow, you are really on to something here.

      • @Hunter

        Also, the rising run away temperatures could start mutating water loving reptiles into godzilla type monsters that could ravage our cities. …
        Wow, you are really on to something here.

        The Japanese thought so. ;-)

    • “Bob, as Rud pointed out, collapse is a physical impossibility.”

      I didn’t see Rud post any experimental proof of that claim.

      It’s funny how demanding skeptics are of CO2’s warming influence, but they’ll happily accept other parts of mainstream science that are more convenient for them.

    • “Let’s see now. How long would it take 3.8W/m2 to melt through a 2-mile thick slab of ice?”

      Now, if the temperature remains below freezing, how long will it take?

    • Lolwot,

      Yeah, it’s happened before, it’ll happen again, it’s all part of the Gaia cycle.

      Ice age cometh, I thought that’s what the climatologists were saying in the 70s.

    • Droege, Lolwot.
      For the geology, see svc.gsfc.nasa.gov/stories/Greenland
      For the melting rate computations, see Robinson et. al, Multistability and Critical Thresholds of the Greenland Ice Sheet, Nature Climate Change doi:10.1038/nclimate1449 (2012)
      Those who live in glass houses should not throw stones, or make easily disprovable assertions, or natter on without first reading my book. Footnotes 136 and 137 to the Arts of Truth, which you both practice. And as the introduction makes plain, that is not a complement.

    • Rud, do you know if anyone has considered how the land may change as the ice melts? After a couple tens of thousands of years, might that bowl become less concave?

    • (I might be wrong, but I think Tamsin Edwards may have considered this and ruled it out.)

    • Aaron, I don’t know of one. Obviously there would be isostatic rebound. But the elevation difference from the bottom center to the rim is about minus 500 meters MSL to about plus 1500 meters MSL. Doubt rebound would do 2000 meters any time soon. I

    • Rud,

      You say the collapse of the Greenland Ice sheet is geophysically impossible, and you cite Robinson, who says this

      ” We estimate that the warming threshold leading to a monostable, essentially ice-free state is in the range of 0.8–3.2 °C, with a best estimate of 1.6 °C.”

      So if that’s 1.6 above pre-industrial or now is the difference between being half way or a third of the way there.

      The NASA site you referenced gives 50 gigatons per year mass loss from the Greenland Ice Sheet, but recent data

      http://congrexprojects.com/docs/12c20_docs2/2-grace_esa-clic_forsberg.pdf?sfvrsn=2

      gives a value between 1000 and 2000 gigatons per year.

      And you want me to read your book.

    • Bob, would you care to point out exactly where you found the “1000 to 2000 gigatons per year” figure?

    • Phatboy,

      It;s in the cite from the DTU Space National Space Institute, look for the yellow ovals

    • Do you mean the yellow ovals around 2010 and 2012, which are 419 and 556 GT respectively?
      That’s still a long way from 1000 – 2000 and, in any case, two outliers do not a trend make.

    • For those demanding experimental proof of Greenland not being able to physically collapse its ice sheet:
      The experiment is to find a large bowl, put ice in it and let it melt.

    • “The experiment is to find a large bowl, put ice in it and let it melt.”

      Hardly, according to climate skeptic logic such an experiment merely tells you about the behavior of ice in a bowl and nothing about the Greenland ice sheet.

      Unless you assume all other things are equal. And apparently (according to climate skeptics at least) that isn’t allowed.

    • Greenland ice sheet mass loss is of course nonlinear with observed acceleration in recent years:

      http://www.nature.com/nclimate/journal/v4/n4/full/nclimate2161.html

      Just as with NH sea ice, which is also declining in thickness in a nonlinear way, the thinning of Greenland’s ice sheet will only accelerate into the future. Because of the large inertia of the ice sheet, the current acceleration is the result of past decades of forcing. Current GH gas levels have yet to make their full impact on the ice sheet.

    • Phatboy,

      The numbers 419 and 556 are the changes from the previous year not the current amount of loss/gain.

    • Jim Cripwell

      R. Gates, you write “Just as with NH sea ice, which is also declining in thickness in a nonlinear way,”

      Correction. This should read “Just as with NH sea ice, which WAS also declining in thickness in a nonlinear way,”

      The data is ergodic, and there is no indication that Arctic sea ice is still declining in a nonlinear way. In 2013, this decline stopped. Whether it will resume again, or what will happen this year, and in future years, no-one knows. If you look at the forecasts made on behalf of ARCUS, no-one, and I mean no-one, has been able to forecast Arctic sea ice minimum consistently. Just ask Bob Droege.

    • Bob Droege,

      Ah yes, I see now.
      The label on the X-axis says: “GT/yr”
      So what that’s saying is that Greenland, in the space of a decade, went from gaining ice mass at a rate of 1000GT/yr to losing it at a rate of over 1000GT/yr!

      Alternatively, the “GT/yr” label might simply be a typo.

      That’s the funny thing about us humans. We’re very quick to so unquestioningly accept anything that appears to bolster our beliefs, prejudices and biases, regardless of whether or not it’s even plausible.

    • Marble-mouthed the Greenland specialist
      Faced with factual ice in dish.
      ================

    • “there is no indication that Arctic sea ice is still declining in a nonlinear way. In 2013, this decline stopped.”
      _____
      Of course this is completely inaccurate and reminds me of all the fake-skeptics who were certain the sea-ice was recovering in 2008 and 2009 after 2007’s big decline. Then along came the monster decline in 2012, and it only natural for the unscientific fake-skeptics to try and suggest the long-term decline “stopped” in 2013. This looking at one year or one myopic metric for the long-term GH gas induced energy gains in the Earth climate system is par for the course for fake-skeptics.

    • Jim Cripwell

      R. Gates, you write “Of course this is completely inaccurate and reminds me of all the fake-skeptics who were certain the sea-ice was recovering in 2008 and 2009 after 2007′s big decline.”

      Here is a prime example of ” nailing one’s colors to the mast”. Future data on Arctic sea ice hangs like a Sword of Damocles over what you have just written.

      It is virtually certain that we are going to be putting as much CO2 into the atmosphere as we can financially afford. I have a long memory.

      And by the way, what I wrote is completely accurate, though no warmist would ever agree. If you will read what I wrote I made no claims whatsoever about Arctic sea ice recovering. I said no-one knows.

    • Phatboy,

      I don’t you can find a credible source that would say that the collapse of the Greenland Ice Sheet is impossible.
      Yet you cling to that belief no matter what evidence says otherwise.
      It’s happened before, it can happen again, goes to show that stating the collapse of the Greenland Ice Sheet is impossible is contrary to the evidence at hand and confirms that you are indeed biased.
      Those who say it won’t collapse because it’s bowl shaped aren’t thinking clearly, there is too much evidence that it is not bowl shaped. Clearly Greenland has plenty of coastal mountains but there a plenty of low areas providing little resistance to water flow or ice flow for that matter.

    • Bob Droege,

      You don’t even acknowledge that you got it wrong on the ice loss, before attacking me over something else.
      Some might call that dodging the issue.

    • “Future data on Arctic sea ice hangs like a Sword of Damocles over what you have just written.”
      _____
      Having no “skin in the game”, no “sword” can ever be held over my head. The data, the basic physics, the trend all points to an ice-free summer Arctic this Century– a remarkably fast change if it does occur. If it does not occur, and somehow the trend reverses, then I “win’ because I have a chance to learn something new about the Earth system. You see, a true skeptic can never lose as they have only knowledge and understanding as their goal, unlike fake-skeptics, true-believers, and other non-scientifically motivated pundits.

    • Jim C. said:

      “If you will read what I wrote I made no claims whatsoever about Arctic sea ice recovering. I said no-one knows.”
      _____
      But we do know– or more accurately, have a high certainty of. We have more data on the Arctic sea ice then at any time in human history and we can most clearly see that it is not recovering, but is continuing a long-term downward spiral to an ice-free condition. To suggest otherwise is to try and take a tiny little uncertainty monster (that would barely fit on an ice-cube) and make it into something huge.

    • Glad this little reply got so much attention. I wrote up and offered to Dr. Curry today a rather more precise discussion of Greenland, complete with hyperlinks to get rid of a lot of the factual nonsense brutted above. She liked it, and might wrap into a subsequent larger post about scenario uncertainty since that, not Greenland, is the topic.
      Was easy since based on the past book, just needing updating and sharpening per this thread. Found more good stuff.

      Rather than opine, why not research? Rather than believe the first Google item found, why not cross check and validate? Results can be rewarding, and even sometimes astounding.

    • Phatboy,
      I have not attacked you, just your arguments.

      I would say you have difficulty reading a graph.

      So is Greenland losing or gaining ice?

    • I’ll just say I am open to any discussion of arctic sea ice loss or the condition of the Greenland Ice sheet. Or Antarctic sea ice or the ice sheets there as well.

    • Bob Droege,

      No, it’s you who takes a graph at face value when there’s a rather obvious error in it.
      And then you refuse to accept that the conclusion you come to is completely implausible.

    • Right Phatboy,

      So how does that error compare to “as Rud pointed out, collapse is a physical impossibility.”

      Just asking

    • bob droege, it’s not about the same thing and I never said it was.
      In fact, you’re the one who brought it up in the first place.

      Stick to the point. Do you agree that your ‘1000 to 2000 gigatons per year’ statement was in error?
      If not, then we have nothing further to discuss.

    • It could exceed 1000 by now, if you extend this curve. However, I wouldn’t minimize the rates shown here, as you can see from the sea-level equivalent. There’s no denying that Greenland accounts for a large part of the sea-level rise we are seeing today.
      http://tothepoles.files.wordpress.com/2013/11/greenland-mass-grace.jpg

    • Also this is the bedrock elevation. Looks like there would be some ways out.
      http://upload.wikimedia.org/wikipedia/commons/8/8b/Topographic_map_of_Greenland_bedrock.jpg

    • Jim D, your graph, as well as the one Bob referenced, show a loss of around 2500 gigatons over the decade of 2003-2013.
      But Bob is asserting that the graph shows an ice loss of between 1000 and 2000 gigatons per year, on the strength of what can only be described as a typo in the Y-axis label of the graph.

    • phatboy, as you can see, 1000 Gt is about 3 mm of sea-level rise just due to Greenland alone. We may get about 1000 Gt in the 2014 melt season. This should be of concern.

    • Jim D, yes there are ways out, as you put it.
      But something’s got to cause a 2-million sq kilometre, 2-mile thick slab of ice to make for the nearest exit.
      And I can’t see that being influenced significantly by an extra bit of summer surface melt.
      If you have some good evidence that this is in fact being exacerbated to a significant degree, anything more than conjecture, then by all means bring it to the table.

    • Jim D, yes, we might have 1000, but then again, we might not.
      The two big melt years, 2010 and 2012, which were statistical outliers, coincided with Icelandic volcanic eruptions, North American wildfires and shifts in the jet stream.
      We may have similar conditions this summer, in which case we might have another big melt, or we may not – time will tell.

    • phatboy, I see that as a growing trend regardless of other factors. It doesn’t take large sections of glacier sliding into the sea to make this a serious problem. If the trend continues to double every 5 years, like it has for the last 10, that is a problem enough. However, that doubling rate would be unsustainable because Greenland would be all melted in 50 years if it persisted, with a 10 meter sea-level rise. That’s just where the current downward curve points by exponential extrapolation. No one has said this can happen, which may be reassuring.

    • Jim D, where’s your evidence that the rate has doubled in 5 years?
      We had two outliers in 2010 and 2012, and, other than that, the steady increase in ice loss has been just as much to do with reduced snowfall as increased melt.
      Look at the graphs in: http://www.realclimate.org/index.php/archives/2011/09/greenland-meltdown/

    • phatboy, it is from the graph I posted. The loss from 2002-2007 was 800 Gt, and from 2007-2012 was 1600 Gt. It doubled in five years.

    • Jim D, the annual rate has not doubled – it’s just the two outliers which make it appear so. The annual mass loss, per year, has been:

      2003: 84
      2004: 148
      2005: 201
      2006: 177
      2007: 244
      2008: 282
      2009: 176
      2010: 419
      2011: 291
      2012: 556

      There is no indication from these figures that 2010 and 2012 are anything other than outliers. However, time will tell.

    • phatboy, you can separately sum the first 5 and last 5 years in your list and find the factor of two growth there too.

    • Jim D, there’s no indication that the underlying rate is accelerating, or going to accelerate. If 2010 and 2012 are merely outliers, and there’s nothing in the data to indicate that they aren’t, this year’s melt should be close to the average over the last 10 years.
      If there are exceptional conditions again this summer, or if the melt really is accelerating, then we’ll probably see a greater than average melt.
      But we’ll have to wait to see what happens this summer – we can’t tell what’s likely to happen from data we have.

    • The melt rate has to go down because the amount of heat transport poleward is going down. If the poleward heat transport goes back up it changes everything but as of right now, with the latest data, the meme that the Arctic is melting is going to be yet another alarmist argument gone bad.

    • In line with the topic, the worst case scenario has the Greenland melt rate continuing to provide accelerating sea-level rises leading to more than a meter well before 2100.

    • Phatboy,
      I already said it was an error,
      now are you going to say that stating that the collapse of the Greenland Ice Sheet is geophysically impossible was also in error.

      And how are you so sure that the 419 and 556 gigatons per year measurements are outliers?

    • -Jim D | April 20, 2014 at 1:47 pm |

      phatboy, it is from the graph I posted. The loss from 2002-2007 was 800 Gt, and from 2007-2012 was 1600 Gt. It doubled in five years.-

      Do you imagine it is going to double in another 5 years?

      If were to have as high a rate as 1000 Gt per year, and it had an average
      of 1000 Gt per year for 20 years, so that added 20,000 Gt by 2034 then this amounts to adding up just over 2 inches [5.5 cm] over 20 years to ocean level.
      Now with such increase would this be something one would call a “collapse of the Greenland Ice Sheet”? Or how many thousands of GT per year, is needed to call it a “collapse of the Greenland Ice Sheet”.

      If instead it averages net loss of 2000 Gt of water [a few times the average flow rate of the Mississippi river], then in 20 years it’s added over 4 inches to global sea level. Would this be a “collapse of the Greenland Ice Sheet”
      or a “total collapse of the Greenland Ice Sheet”?
      If it continued at 2000 GT on average for 80 years, it totals about 17 inches.
      And so nearing 2100, it would have added 160,000 Gt of water to ocean
      and would have melted over 5% of Greenland’s total amount of ice which
      is about 2,850,000 Gt of ice.
      So would such dramatic increase of ice loss amount to average 2000 Gt per year for 80 years, mean that before the year 2100, a person could say
      we have lost a staggering amount ice and it’s over 5% of Greenland’s ice and it’s been a collapse of Greenland Ice Sheet. Or would be better to say it has been a total collapse of Greenland Ice Sheet, which will continue for next thousand years..
      So is 17 inches or less than 1/2 meter of water added to sea level from Greenland by time near the year 2100, something grandchildren will say is
      a collapse of Greenland ice Sheet. or known as the great collapse of the 21st century?
      What could these poor children do then?

      If it double in next 5 years, then double again in another 5 year, then we would be approaching an average of 1000 Gt per year, and by 2034
      it might reasonable to say we might get to 2000 Gt average before the end of century. Though someone could also say that it will continue to doubling- it has a pattern of doubling, hence it’s likely to keep doubling,
      So might claim it’s going to increase to average of more than 10,000 Gt by the end of the century.
      So say it’s early 2030’s, and we have had just over 2″ added to sea level from Greenland ice melting. Obama’s era of “stopping the sea level from rising” is over, and the sea level is still rising
      What should we do about it?
      It seems by this time we probably have launch a couple satellite which are similar to Grace. And have reduced the error in measurement via satellite and other ways measure. And we have longer trend of accurate measurement. And there could other good news. Though in terms of bad news, well probably world is emitting more 40 Gt of CO2, and China and India are emitting most of it. Though it’s possible that China and India have
      run out of “cheap coal”- cheap being defined as less than $200 per ton. Or about 80% increase to current prices. And this could good news or bad news depending up whether these countries are using and have access to large amount of natural gas. Good news being their emissions will go down, bad news is to are in a war due to a desperate need of energy. And /or China [less likely India] has suffered huge economic bubble as did Japan and as did US- lack energy and economic crisis is why they are at war with someone- it could be Russia which has vast amount of energy.
      So got better information and everyone is also a global warming believer, as maybe there as been an astonishing global warming of .5 C, And ICCP
      models have been shown to right.
      So other than some Great Government Program of building massive amounts of sea walls, to mitigate the 2 feet possible rise in sea level in coming 100 years] . A massive job program which could rival the amount money Obama spent preventing to too big to fail, from failing, and finally get the shovel ready jobs, he mentioned.
      So other this wondrous feel good project will save everything. What else
      would we do?

    • Bob,

      1) Not without a long fight.
      2) OK perhaps not impossible, but extremely unlikely – if you have credible data suggesting otherwise, bring it on.
      3) I’m not sure. The data we have so far suggests they’re outliers, but only a few more years data will show this one way or the other.

    • gbaikie, yes, doubling every 5 years is an extreme case. Ten doublings in 50 years give a 1000-fold increase from 1 mm/yr to 1 m/yr, by which time Greenland would be mostly gone, as it soon after that adds up to its 7 meters total. Choose a less extreme, probably conservative, scenario where the loss rate increases linearly by 1000 Gt/yr per decade. Then in 100 years the average loss rate would be 5000 Gt/yr, making a total loss of 500,000 Gt in a century which is about 1.5 meters of sea level and a final rise rate of 3 cm/yr, a foot per decade, and, with a continued linear increase in melt rate, the glacier would be finally gone soon after 2200 with the full 7 meter rise (plus whatever else Antarctica adds by then). Bad case, not but worst case, scenario. The net loss over the last decade may mean that Greenland is already past its tipping point and is not self-sustaining at even current CO2 levels, so mitigation won’t help much unless ways are found of drawing down the CO2 level.

    • Phatboy,
      Take the numbers for mass loss we both posted
      84,148. 201, 177, 244, 282, 176, 419, 291, 556

      Do a least square trend calculation or find the line most likely to describe that series.

      Which give an equation for the mass loss with time, if we assume it continues linearly, and then calculate how long 2850000 gigatons of ice will last.

      I did the problem two ways, once using the data as is and once assuming the 419 and 556 points as outliers and replaced them with the trend values.

      I get numbers in the hundreds, not thousands of years, and the data looks more quadratic than linear.

      you want to try the calculation yourself before I post my answer?

    • –gbaikie, yes, doubling every 5 years is an extreme case. Ten doublings in 50 years give a 1000-fold increase from 1 mm/yr to 1 m/yr, by which time Greenland would be mostly gone, as it soon after that adds up to its 7 meters total.–
      If one is talking ice, this is impossible. If mean the ice has melted before
      leaving Greenland, it’s still near impossible. But if ice is going to melt, it’s massive opportunity to make a dam which make fantastic amount of electrical power. So if it was vaguely possible someone should be planning to make a dam, and in future it looks promising, should actually start building the dam. Flowing 360,000 Gt of water year is very impressive, it about 500 time more than Mississippi, or roughly like making Mississippi
      a hundred time higher and/or faster. So to get close to possible it must be liquid and flowing year around [not freeze when 1/2 the year has no sunlight].
      –Choose a less extreme, probably conservative, scenario where the loss rate increases linearly by 1000 Gt/yr per decade. Then in 100 years the average loss rate would be 5000 Gt/yr, making a total loss of 500,000 Gt in a century which is about 1.5 meters of sea level and a final rise rate of 3 cm/yr, a foot per decade, and, with a continued linear increase in melt rate, the glacier would be finally gone soon after 2200 with the full 7 meter rise (plus whatever else Antarctica adds by then).–
      Again close to impossible, but still not much sea level rise before 2100.
      Though 5000 Gt of ice is less impossible than 360,000 Gt of ice, one still going to have logistically problem with *only* 5000 Gt of ice per year.You don’t have a year long flow, and you flowing into region that in the winter the ocean surface freezes.
      We just had winter where the great lakes froze, and they still dealing with the problem with a lake covered with ice. Even in warmer world where these great lakes don’t freeze in the winter, it seems more 2000 km further north one could still expect the ocean to freeze in the winter.
      So you have limited amount of time each year, you could have as much 6 months or whatever but it’s unlikely to have much flow all year. Or almost ten times the Mississippi river but the flows about 1/2 the year. So say 15 times the Mississippi river. And lets such a Mississippi river flowing ice cubes. One expect that this would have some effect upon the vast region of Gulf of Mexico. It should have some effect upon the warm water of gulf Mexico and if ice cubes persist for some time one expect them pile up at river delta. Or if was ping balls and/or floating cars with a volume of 5000 cubic km per year it create traffic jam at the delta. Or ice is different than water.
      And area it flowing into is the Davis strait, which much smaller and colder than Gulf of Mexico, and already has ice which you adding to. And due to prevailing current the ice flows northward, until it pile up so much divert the current.
      So let’s take ping pong balls of the amount 5000 cubic km dump them in the sea, at rate of 5000 cubic meters in 6 month months of time, so 180 days, and 27 cubic km per day, and a bit more than 1 cubic km per hour.
      So at say speed of 1 km per hour you drag a 1 cubic km of ping pong balls.
      You got 50 of these and drag first out to 100 km beyond the opening. Then whatever is holding them so into 1 km cube is release on all 50 of these 1 km cube km container of ping pong ball.
      Now, if one 1 km cubic the pong balls spread out so they 1 meter deep of pong balls it cover an area of 1000 square km. And 50 is 50,000 square km- in terms of a square is 223 km square. So that’s 50 hours or a bit over 2 days of “work”, which continue for next 6 months delivering the 5000 cubic km in total. Which if 1 meter deep covers 5 million square km. Which larger than 1/2 the area of US- or gulf Mexico would be clogged with ping pong balls deeper than 1 meter deep.
      And Davis straits would much deeper in ping pong balls.
      So there is a volume problem if talking about ice. And other factor is the ice will cool the water it’s in.
      So seems if it’s ice one can’t have 5000 Gt per year flowing out of Greenland. So some number less than this if we talking about ice- and it would complicated trying to figure out what max amount would be permitted, other than 5000 Gt does not seem to be that number.
      But if we could have 5000 Gt and get 1 1/2 meter rise in sea level per century, it doesn’t seem like much of a problem.
      Or with over 9000 years of human civilization, one taking it’s rate of rising sea level and in 1 century of 1 1/2 meter rise one should get less than 4 or 5 centuries of time in which people were unaware that sea level was actually rising. In other words we are of it, and allow for such rise over such long periods of time.
      Such wwrming required to do this we gain massive amounts of farmable land or other benefits, the world given to our children could be much much then world given to us.

    • ” But if ice is going to melt, it’s massive opportunity to make a dam which make fantastic amount of electrical power.”
      I thought attempt to flesh out a bit this “fantastic amount of electrical power”:

      With 1000 Gt flow of water per year, it’s equal flow rate used for power generation of about 50 Three Gorges Dams.
      Or couple percent of total world electrical power used. With constant availability water one constant power at 1,125,000 MW. If valued at 1 cent kw or $10 per MW/hour it’s more than 50 billion dollars worth of electrical power per year. Or worth building if costs were about 200 billion dollars. Three Gorges Dam was about 20 billion with about 1/2 cost being spent re-locating people.
      The remote location and cold conditions would make this costly, but this is based on the assumption conditions will be a bit warmer, and one expect it to remain generally warmer after it’s built and operational.

    • bob droege,

      Look at the residuals. Those two years are outliers by any measure.
      The best trend quoted in the paper you linked to is 244GT/yr.
      Do you have good reason to doubt this figure?
      If you want to play around with your regressions and derive wildly fanciful figures from 10 data points, knock yourself out.
      I’m not going to waste any more of my time.

  9. My apologies. Please ignore that last sentence, Mr. Pielke Sr. I mistook you for Jr.

  10. Very interesting discussion about tail risk.

    i see two point about the argument of fat tailes :
    – first of all choosing one kind of fat tail is taking the risk to suffer from a really unexpected fat tail…
    imagine, ice age, economic downturn causing general revolution, war…
    the error of AGW fan is that they are not accepting other risk… the economic risk.
    for exemple they ignore that economic development is the best protection agains climate extreme.
    they also ignore that knowledge, technology, errors, are good school to react to blackswan events.
    GMo might be frightening, but mastering GMO may save from any species going crazy on earth like it happen for Irish potatoes, or grapevine disease, or rabbit disease… same for climate change or zombie attack. alarmist forget what is an active defence. they imagine we sit like couch potatoes waiting for the end of the world, and so they ask us to panic.

    the big question that i’ve heard about blackswan event is what nassim Nicholas taleb calls “Convexity”/”concavity” alias “antifragility”/”fragility”,

    it is clear that the fear of serious climatologist alarmist is feat of concavity…
    ther error is the myopia on CO2 only…
    soot, CO2, land usage, are recent change in climate, and may cause anything.
    so trying to limit CO2 is only a small part of the question.

    gaining in power to solve the unexpected, by technology progress, economic development, is more important than preventing CO2.

    by the way technology have already solved CO2 problem, and not with the expensive intermittent subsidized renewables…

    and what delayed that revolution is :
    – academic consensus
    – terror against dissenters
    – scientific frauds
    – pal review, and other pathological review
    – incompetence in experimental science
    – focus on theory and model more than on experimental results
    – general groupthink and mutual assured delusion
    – Kuhnian fear to change of paradigm
    – Malthusianist ideology used as bias to reject positive hypothesis

  11. Kerry Emanuel … Coming Ice Age Denier

    “This means talking not just about the most probable middle of the distribution, but also the lower probability high-end risk tail, because the outcome function is very high there. ”

    Why ignore the coming big freeze Kerry? Pretend to be a real scientist for once. Talk about both ends of the distribution. Not just the one that pays your bills. JC SNIP

  12. Dr. Curry, your argument errs on several elementary grounds, but first let us discuss how Dr. Emanuel’s argument errs more fundamentally.

    Dr. Emanuel wonders if “scientists” ought discuss or hold back discussing rational conclusions that are somewhere in the probability distribution — and having uncertainty of what the pdf is does not negate that the pdf does map these risks as non-negligible, so your point there is completely ineffectual — in a way reminiscent of the phrase, “Why should I share my data with you, when…?”

    If Science has a job in communication of future speculation, it is hardly to hold back and limit that speculation for ulterior reasons, be they credibility or alarmism, erring on the side of least drama or to support the status quo or to attack the status quo. Give the full and forthright picture, and for the pdf choose those pdfs which are simplest in terms of assumptions, most parsimonious in terms of exceptions, and most universal in applicability, until such time as new observations require amending the pdf collection.

    This “Open PDF” approach would wipe out all Dr. Emanuel’s paternalistic concerns, and your own, as well. We could each of us then consider based on our own individual risk tolerance and uncertainty tolerance what value we privately place on the options before us, and arrive at a figure for the price of CO2E emission we would demand from those on the Open Market who wish to buy up rights to emit, as well as of the penalty we ought demand from those who steal more CO2E emission than is their due.

    Simple. Parsimonious. Universal. Accurate, or very nearly true.

    • Huge, huge problem here, Bart. You don’t appear to understand probability and statistics very well. Not surprising, as it seems to be quite common.

      Anyway: There is no well-defined meaning for the pdf you recommend.

      Talking about a “simpler” pdf still assumes that such a thing exists. Ony it doesn’t. The climate sensitivity is not a pdf; it’s a well-defined value. The fact that we don’t know what it is does not change that fact.

      There are a number of other problems with your post, but they hardly warrant the time or effort to respond to them. It’s somewhat entertaining that the only response you can imagine involves CO2 emissions, though. Quite telling.

    • fizzymagic | April 19, 2014 at 1:48 am |

      Wow. I guess I’ll have to give back my freaking degree, if my understanding is so freaking poor.

      Nothing in the conditions I describe require the meaning be well-defined. Hence the broad categorization of “non-negligible” outcomes, as opposed to a more formal statement. So I don’t recommend a single pdf, as you allege. Learn to freaking READ HARDER.

      And how do you freaking conclude that freaking climate sensitivity is a single well-freaking-defined value, as opposed to a multifreakingvariate function, even a step freaking function, and plausifreakingbly not even that? The freaking fact that we don’t freaking know even this about climate freaking sensitivity in some abstract Platofreakingnic sense does not preclude us freaking establishing that there are pdfs (ie, a collection of valid ‘explanations’ of likely outcomes given what we do know in a Newtofreakingnian sense) that we may find to be accurate or very nearly true based on the simplification of assumptions, parsimony of exceptions and universality of application of inferences from observations to date.

      As you freaking look at my freaking CO2 emissions in your freaking crystal ball able to tell, quite tell, by your freaking mystical powers whatever it is you want to freaking insinuate, entertaining us all in turn with your entertainment, perhaps you can freaking explain the air of arrogant smugness pervading your own emissions?

      Because the simplest, most parsimonious, most universal explanation given what you’ve written is that you don’t know how to freaking read.

    • Wow. I guess I’ll have to give back my freaking degree, if my understanding is so freaking poor.

      I don’t know about the value of your degree; if it is related to probability or statistics, then I would venture that you didn’t get your money’s worth.

      From your response, it looks like I hit some kind of nerve. That must explain your imputation of smugness. I read your post quite thoroughly, thanks very much. And your insistence that our ignorance concerning climate sensitivity be expressed as pdfs is Just Plain Wrong. It’s wrong from a Bayesian standpoint and it is wrong from a classical statistics standpoint.

    • fizzymagic | April 19, 2014 at 11:30 pm |

      It’s also wrong from a reading comprehension standpoint, as it’s not what I wrote.

      Newton and Hooke had this debate three hundred years ago. Newton stomped all over the Bernoullian idea of mapping ignorance at all, and quite rightly. We can’t map ignorance, we shouldn’t even try. We should have the humility to recognize that our ignorance is a vast and indefinable ocean, beyond the shores of our conception or control, and where we stand on that beach flinging pebbles into the great darkness, we might extend that coastline a little bit.

      That’s our job: extend the boundaries of what we do know, not pretend to ever diminish the scope of what we may not yet realize.

      So we can indeed propose a single pdf, or a collection of pdfs. Each pdf is an attempt to explain observations, an inference drawn from data. What pdf or collection of pdfs simplifies our assumptions, is most parsimonious of exceptions left out of the pdfs in the set, is most universal in encompassing all observations with the relations forming the pdfs, we hold to be accurate or very nearly true until such time as new observation require us to recompose our pdf set.

      THAT is Science, founded directly on the 300-year-old Principia that came out of the same debate, that covered the same deprecated ground, as you’re trying to rehash now. Which is why I hold my education to somewhat higher value than I hold yours.

  13. pottereaton – Thank you for the feedback. On Fivethirtyeight, that is Roger Jr. :-)

    Roger Sr.

  14. In my recent Climate Dynamics paper (http://bit.ly/1h9WrME), with Q+A: (http://bit.ly/1i2lqlr) I quantify the pdf’s including the fat tails for natural global,temperatures for changes from annual to 125 year time scales.
    Specifically, if we treat the problem classically with bell-surves (Gaussians), then the probability of the warming is between one in a hundred thousand and one in ten million. However due to the fat tails, the extremes are far more frequent: at least one hundred times more so. However we can still comfortably reject the natural warming hypothesis.

    I think that we’re in the process of taming the natural variability and that even the black swan events are well characterized (the pause and post-war cooling also fall out easily as natural variability, but this is under review!).
    If this is true, we’ll finally be able to move on beyond often sterile debate about “possible” extremes to discuss the actual extremes. Let’s move on!

    • Hi Shaun, good luck getting published the 1940-1975 cooling is natural variability (that is a typical ‘denier” talking point), although I agree with you that is the case. The problem is that 125 years is insufficient time to provide any kind of statistical basis for black swan (extreme weather events) or dragon king events (abrupt climate change).

    • Prof Lovejoy

      Unfortunately my opinion of this paper is very negative, even on cursory examination (a week ago). One reason is the lack of basic statistical analysis. As I recall, residuals for temperature regressed on CO2 forcing for 1880 onwards are displayed and clearly show poor fit over 1880-1940 (less obviously 1940-75!). This should be an immediate red flag for the use of regression estimates. Memory suggests even the IPCC say this period has to be accounted for by other (natural) ‘forcings’. A basic property of the residuals for a regression with a constant term is they must have zero mean (ie sum to 0). Remarkably, these residuals are nevertheless presented as all possible natural variation over 1880-2000. Zero mean time series is such a severe constraint on what constitutes ‘natural variation’ that I cannot believe it is satisfactory.

      On the last point, the implicit idea in many climatology articles that without man-made ‘forcings’ temperatures would follow some kind of Eden-like ‘martingale’ process just seems implausible.

    • Hi Shaun, what is your estimate of the amount of the secular trend caused by increased OHT as depicted in the reconstruction of Gulf Stream transport by Lund et al 2006? Since the OHT decreased from the MWP to the LIA and then increased to the modern warming period, it would be rather difficult to claim co2 as the cause without some evidence it is so. The lack of correlation would say no. If you started your examination starting at some point in the LIA how do you justify disregarding the increase in OHT?

    • Prof. Lovejoy is spot on. I would only add that the poorly calibrated temperature data during the WWII years has caused much grief in fitting the historical profile. The following is a natural variability fit to the GISS data which requires a narrow yet significant correction during WWII to achieve high correlation:
      http://imageshack.com/a/img842/2517/r2f8.gif

    • Shaun Lovejoy | April 18, 2014 at 12:24 pm |

      Thank you for your paper. It’s nice to see the classical approach used with rigor, and communicated so clearly.

      You should hold seminars on the method. I know most of the climate community would benefit from a refresher in the math.

    • I think the 1910-1940 rise was helped by an 0.2 C bump from increased solar activity towards the mid-century peak, and the 1940-1975 cooling of about 0.2 C was due to the increased use of coal and the oil boom that went into growing aerosol generation (so-called global dimming). This was all against the background CO2 rise. These two 0.2 C perturbations of the 20th century fall within Lovejoy’s standard deviation of the background.

    • I think Grant Foster’s recent post on these extremes and non-linear extremes is worth reviewing:

      http://tamino.wordpress.com/2014/04/18/non-linear-trends/

    • So, the July temperatures in the 1930s in Moscow were as high as in the 2010s. Where’s the beef?

    • Edim,

      The central theme is that when it comes to climate extremes, looking at linear versus non-linear background trends, the non-linear are clearly the way to go:

      http://tamino.files.wordpress.com/2014/04/july_poly.jpeg

      We can clearly see the big difference in the modern warming trend for Moscow versus the 1930’s using the 4th degree Polynomial, and moreover, the 2010 heat wave fits the modern warming non-linear trend far better than a simple linear fit.

    • When was the last black swan event in climate? Dryas? Do we know what happened then?

  15. Judith wrote:
    Unverified hypothesis about fat tail events are NOT what we KNOW. Presenting this as knowledge rather than speculation, and unduly focusing on it, is alarmist.

    Tail events aren’t presented as “speculation”, they’re presented as possibilities.

    They’re not presented as “knowledge,” they’re present as a result of a lack of knowledge, i.e. of uncertaintly.

    There is never going to be complete knowledge of the future climate system. The question then, is how you make decisions in light of imperfect knowledge? Many think that means you don’t make decisions, or you make a decision to do nothing, when in fact we don’t do that in other areas of our individual or societal lives.

  16. Chaotic distributions have fat tails.

  17. Pingback: Black Swans And Dragon Kings | Transterrestrial Musings

  18. David in Cal

    There is no real-world probability distribution for sensitivity. Climate sensitivity is (presumably) a single, fixed number, which happens to be unknown. Discussing it in terms of probabilities is misleading, because it sounds like probability measures of real variation. E.g., it’s a fact that there’s one chance in four of getting two heads in row when flipping a fair coin. This fact could be verified by repeatedly flipping the coin. However, there’s no way to verify a probability distribution of climate sensitivity, because that distribution doesn’t reflect variation in sensitivity. Instead, it represents one’s personal degree of ignorance.

    • Jim Cripwell

      +1000

    • You’re wrong about the coin. It’s trajectory is deterministic and the probabilistic description is purely a result of the limitation of our knowledge. But that error is not even relevant from a policy point of view. Frequentist probabilities are indeed useless for describing unique events, such as all of human history or entire climate trajectories, because we only get one trial (reality). But there is nothing to preclude us from rationally accounting for the limitations of our knowledge while maintaining consistency between our beliefs conditional on seeing X versus those conditional on seeing Y, and one of the best ways to do that is with probability density functions.

      To go from beliefs to decisions requires the addition of a loss function, which has its own manifold complexities and difficulties to formulate, but there isn’t a good reason for eschewing internal consistency at the beliefs stage. In fact, this kind of know-nothing approach can increase alarmism by, as Nic Lewis has shown in some examples, improperly using uniform prior beliefs (“we know nothing”) rather than prior beliefs that have a mode around the values that are actually most likely.

  19. In this article, you are using very dubious ethical reasoning because of your ideological commitments that predispose you against taking climate change as a real threat. You probably have an insurance for dealing with medical events, for dealing with a fire in your house, for dealing with you driving your car against the wall. You know very little about the likelihood of these events or their costs, certainly less than we know about the reality of climate change. You insure for your drastic life events them precisely because the consequences can be very high, not because you know what the likelihood is. The consequences of climate change CAN be very high. That is sufficient for taking action.

    • We’ve covered this ground before. I have fire insurance; i do not have earthquake insurance (unlikely in my location and the cost is high); and I didn’t even consider asteroid strike insurance. If i really wanted to be careful, if i get an infection in my foot I would cut off my leg to make sure the infection doesn’t spread. You can see where this line of logic leads . . .

      • David Springer

        Paul Woland | April 18, 2014 at 12:51 pm | Reply

        “You probably have an insurance for dealing with medical events, for dealing with a fire in your house, for dealing with you driving your car against the wall. You know very little about the likelihood of these events or their costs, certainly less than we know about the reality of climate change”

        Wrong.

        We know with reasonable precision the likelyhood of those events because they actually happen. For instance there are about 100 million houses in the US and about 50,000 of them burn down each year.

        How often does catastrophic global warming from human CO2 emissions happen?

        Tool.

    • paulie, you forgot to mention that anthro CO2 is as certain to cause climate catastrophe as smoking tobacco is to cause cancer. And oh! those poor polar bears.

    • Jim Cripwell

      Paul, you write “In this article, you are using very dubious ethical reasoning because of your ideological commitments that predispose you against taking climate change as a real threat.”

      I find this interesting. When I read what our hostess writes, it convinces me that she is absolutely convinced that CAGW is a very dire threat.

    • I have insurance for known risks that have been seen before, none of us has seen CAGW.

    • Paul,
      The fallacy that climate oobsessed people abuse regarding insurance raises real questions about the level of critical thinking you true believers can muster. Medical insurance is based on measureable risks that actually exist: Health, Property & Casualty, are all measureable risks. “Climate change” is not. It is a circular set of claims that explains everything and therefor nothing. The fact that leaders in the reinsurance industry admit that storm losses have not increased, even as their reinsurance premium charges have increased dramatically, tells something is amiss in the pricing of risk.

    • curryja | April 18, 2014 at 12:55 pm |

      This specious slippery slope argument brought to you by Irrational Fallacy R Us (TM).

      Irrational Fallacy R Us (TM) – providing an easy out to serious objections since Mom first discovered friends jumping off bridges.

    • “you can see where this line of logic leads . . .”:

      To selective reasoning through failed analogies.

      Cutting off your leg is a single, simplistic action. The downsides are obvious and clear.

      Mitigating against ACO2 emissions as a potential threat takes many forms (non of which are simplistic), and the cost/benefit ratio of those different forms are highly uncertain. Not to mention the accompanying uncertainties regarding related positive and negative extermalities from reducing fossil fuel usage (geo-political costs, environmental costs, the costs of health impacts, the costs of lowering energy access, etc.).

      So once again, Mr. Monster just ups and walks out of the room as you are writing, Judith?

      Interesting how he just conveniently disappears, eh?

      • And the economic downsides of rapid decarbonization of global energy supply . . . are not convincingly portrayed by the IPCC AR5 WG3 report (more on that in a forthcoming post). Cutting off your leg is an example of the cure being worse than the disease, which is a good analogy for some of the so called ‘climate change cures’

    • are not convincingly portrayed by the IPCC AR5 WG3 report (more on that in a forthcoming post). Cutting off your leg is an example of the cure being worse than the disease, which is a good analogy for some of the so called ‘climate change cures’

      Paging Mr. Monster. Mr. Uncertain T. Monster. Emergency call from Judith Curry on line #2. She needs to talk to you. STAT.

    • It all depends on what kind of infection is in your foot and whether or not cutting off your leg will save your life.

      Could go either way.

    • Steven Mosher

      Paul

      “The consequences of climate change CAN be very high. That is sufficient for taking action.”

      Then you go ahead and take action. The problem isnt in finding a ‘reason’ to take action. uncertainty can be a reason to take action or not take action. Knowledge can be a reason to take action or not take action.

      the issue is what kind of reason are you required to give to ME, to act.
      Further, rationalizing action is not the problem. The problem is WHAT ACTION, and by whom

    • ” You probably have an insurance for dealing with medical events, for dealing with a fire in your house, for dealing with you driving your car against the wall.”

      CAGW/decarbonization is nothing like insurance. Decarbonization is like buying another house or an extra car, rather than insuring against their damage or loss. And bankrupting yourself in the process to boot.

    • I have fire insurance; i do not have earthquake insurance (unlikely in my location and the cost is high)

      In NZ where the risk is assumed to be high,earthquake insurance is mandatory ( coupled to all risks policy) and premiums are still relatively low .

    • Fire insurance is affordable precisely because for most a home fire is highly unlikely, until such time as humanity stops burning coal and returns to the use of candles for light.

    • It’s interesting that Judith has such a high degree of certainty about the economic consequences of CO2 mitigation.

      Applying her own reasoning in the post, we’d have to conclude there is no basis for such alarmism due to scenario unceratinty.

    • There needs to be a debate about the likely proposed carbon phase-out over 50-100 years, and its cost. The IPCC WG3 SPM portrays it as no big deal, certainly when compared to adaptation, resilience and damage costs due to warming. Mitigation turns into a reasonably small investment against further such costs with the side effects of clean energy, energy independence, and energy efficiency. Economic alarmism (worst-case scenario thinking, you might say) has run rampant on this topic, and has many convinced, even without numbers to combat the IPCC WG3 numbers. They talk in terms of the strawman of immediate decarbonization, when the proposals are far from immediate and give technology plenty of time to develop.

    • “It’s interesting that Judith has such a high degree of certainty about the economic consequences of CO2 mitigation.”

      When talking about the the magnitude of climate change, she invites Mr. Monster in for a drink. When she’s talking about the economics of mitigation, she kicks him to the curb.

      ‘Prolly just coincidence.

    • Latimer Alder

      @paul woland

      ‘You know very little about the likelihood of these events [medical, fire, car] or their costs, certainly less than we know about the reality of climate change.’

      Au contraire. We know a great deal about the likelihood of all those events and their range of costs. Having that knowledge is the basis of the insurance industry.

      There is no comparable knowledge about climate change.

      Your reasoning is faulty.

    • curryja @ April 18, 2014 at 2:23 pm

      Your broadening perspective and growing comprehension of the broad range of risks faced by society, where climate change ranks in that range of risks, and the economic and policy implications of proposed mitigation strategies has changed a lot in three years.

      I am amazed and greatly admire you for it. It shows what can happen when scientists, and in fact all experts, are willing to listen to and engage with others from outside their own discipline and area of expertise. I feel you have done that in two important ways.

      First, you are running you own consulting business in which you directly apply applications and knowledge from climate science. You are having to respond to the needs of your clients and you are getting feed back from them as to how well you are doing at meeting their needs.

      Second, you encourage people with expertise from other disciplines to contribute on your Climate Etc.. And you learn from them. From my admittedly biased perspective, I suspect you have learnt a lot from engineers, economists, policy analysts. Some who come quickly to mind are: Latimer Alder, Manacker, MW Grant, IAN888, Faustino, Johanna, Roger Pielke Jr, Richard Tol (sorry for those whose names are not at the front of memory as I write this quickly),

    • For those claiming phasing out carbon over 50-100 years is no big deal and that mitigation is not a high cost choice:
      How much crack are you smoking?
      The so-called renewables are a failed joke:
      Wind does not work as a base load. Solar, the same. Climate obsessed people will not permit nuclear. Biofuels are a cruel distortion of the foods market. There is no sequestration technology available or even close to coming to market.
      Pointing that out is not alarmism.
      And quoting some UN report, after it has been clearly documented that the IPCC reports are not based on science but politics is almost cynical.

    • Considering the percentage of foot infections that result in leg amputations, fat tail indeed.

    • This is more like amputating your leg because you think you might stub your toe and get an infection one day.

    • It can occur with infections that do not respond to treatment.

      But it is pretty common with diabetes, about 80,000 per year.

    • “How often does catastrophic global warming from human CO2 emissions happen?”
      ______
      This is one of the funniest things Springer has ever said, and I wonder if he even realizes how absurd it was.

      So here’s a little thought experiment. Pick whatever odds you want for the possibility of catastrophic climate change- 1in 10, 1 in 100, 1 in 1000. Whatever, it doesn’t matter. Now imagine a gun with that many places for bullets in the cylinder. Let’s use the 1 in 100– so we place one bullet in the cylinder, spin that cylinder and place it up to your child’s or grandchild’s head. Would you do it? Ignoring the potential for catastrophic climate change is no different, except that gun is up against heads of billions.

      • David Springer

        So how often does catastrophic global warming from anthropogenic CO2 emissions happen, Gates?

        It’s not a trick question.

    • curryja | April 18, 2014 at 2:23 pm |

      And the economic downsides of rapid decarbonization of global energy supply.. is specious.

      There are no long term stationary energy sources that emit CO2E that are today more economical over their lifetime to build new than equivalent long term stationary energy facilities that do not, even discounting a carbon price. None.

      The price of solar energy is dropping exponentially. By 2020 — which is about the first year such a facility could go into production if one were beginning the process of planning and development today — the price of solar will be below the price of oil, coal, and conventional biomass. Within a decade, solar will cost less than any form of natural gas in such applications. As the lifespan of even a natural gas electricity generator is so long, for the majority of its operating life the plant will be a net bad investment.

      Wind is expected to have similar price trajectory. Hydroelectricity in the pumped and micro-hydro forms, is already less expensive and only about 8% exploited in America.

      There is no fiscally responsible argument for long term stationary power generation emitting CO2E. None.

      For transportation, the argument is slightly different. It’s unlikely that energy density of a mobile fuel or any form of power storage will economically beat gasoline in the foreseeable future, barring truly unpredictable technological innovation. On the other hand, it’s been possible to turn organic wastes into drop-in gasoline substitute for decades, and the cost of that process too is falling exponentially.

      While it emits CO2E, it doesn’t emit new CO2E pulled up from the ground, but rather from the natural carbon cycle, so arguably not as bad a thing. Moreover, where such synthesis is made by pyrolysis, the majority of carbon becomes biochar, which efficiently sequesters carbon far more effectively than the routine natural carbon cycle.

      So, starting with “economic downsides of rapid decarbonization” is pure fiction.

      • If the price of solar becomes competitive with fossil fuels, it will start replacing fossil fuels (that pesky law of supply and demand). However since it is not competitive now, building now is not cost competitive regardless of when it does become competitive.

    • Talking about asteroids, we see this today.
      http://www.huffingtonpost.com/2014/04/19/asteroids-cities_n_5178708.html
      Alarmism or just information?

      • Alarmism is exaggeration of the risk associated with an ‘ought’ (e.g. urgent action needed). I don’t see any of that in the asteroid article

    • That’s the crux, isn’t it? A lot of skeptics say that the science pointing to a 4 C rise by itself is alarmism. Is the WG1 report alarmism when it summarizes temperatures, sea-level and rainfall changes without reference to human impact or needs for mitigation? Alarmism or just information to be aware of?

    • curryja | April 19, 2014 at 2:53 pm |

      So would the exaggeration of “the economic downsides of rapid decarbonization of global energy supply” be economic alarmism?

    • Mitigating and adapting to moderate climate change is not very expensive–0.6 of GDP a recent estimate.

      Following the advice of hysterics costs everything.

      Fighting black carbon, reducing deforestation, continuing the inexorable rise of renewables, pushing in a measured way for nuclear, finding a CO2-free substitute for cement–a drop in the bucket.

      Forcing the world to go back to prehistoric levels of energy consumption? A little more.

    • Tom Fuller | April 19, 2014 at 11:40 pm |

      Ah.. but _enabling_ the world to return to prehistoric levels of carbon burning while still satisfying every want and addressing every misery, that is the promise of technology, advancing exponentially and dropping in price, while the cost of burning only really goes up.

    • Bart continues to push solar crackpottery.

      Yes, you can find shills from the solar industry to cite figures that hide the subsidies, the necessary fossil fuel back-up capacity, and the lower quality of an intermittent and uncertain source. But the EIA; the most careful work that I’ve seen, by Severin Borenstein at the Berkeley Energy Institute (I’ve linked to his stuff in the past, because he also provides a good tutorial on some of the complexities in defining and measuring the “cost” of a power plant); the market test where no unsubsidized solar PV is ever adopted except for remote applications off the grid; and the fiascoes in Spain and Germany all strongly indicate that solar PV is not remotely competitive as a source of grid electric power.

      Bart forgets his Newtonian criteria (which aren’t universally valid anyway) when it comes to his solar credulity.

    • stevepostrel | April 20, 2014 at 4:18 pm |

      the subsidies,

      Huh. Care to compare the ratio of solar that’s subsidized compared to the ratio of fossil? The amount of solar subsidies throughout history to the amount of fossil subsidies? The potential of solar to the potential of fossil? The cost trend of solar to the cost trend of fossil?

      I’m no supporter of subsidies, but if you’re going to tar with the subsidy brush, remember to remove the beam from fossil’s eye before complaining of the mote in solar’s.

      the necessary fossil fuel back-up capacity,

      Bzzzt. The only people who think fossil fuel back-up capacity is necessary are people who fall for fossil fuel crap logic. Geothermal is a far cheaper and more reliable on demand baseline power source than fossil in any form, over the lifetime of a new facility. Pumped hydro is a far cheaper and more reliable back-up, and has the bonus of being able to be run backwards and efficiently store excess power from other cheap sources like solar and wind. There is zero necessity for fossil fuel back-up capacity.

      the lower quality of an intermittent and uncertain source.

      *squint* You want to talk about the quality of coal, that requires arbitrage with back-up hydro to prevent costly close-down and start-up cycles off peak?

      Care to look at the historical price variations in natural gas, the most price volatile commodity ever?

      Care to speculate on how long before some nimby backlash shuts down fracking for no other reason than that some tinfoil hat wearing wingnut thinks it’s what gave their cow two heads?

      Have a look at these price studies by people who don’t do business, and don’t think like businesspeople, who speculate on ‘minimum’ cost as if there is ever going to be a difference in real business between the minimum and average cost, because the people who can’t deliver at the minimum get driven out of the Market. These reports do not well match the way business works, nor the progression of the CSPV already in the technology development pipeline.

      As for universal validity of Principia, go ahead, actually present your reasoned argument with examples and numbers. If you do it every bit as well as the above comment.. Newton’s safe for another day.

    • George Turner

      Bart, just how on Earth do major oil producing states both subsidize fossil fuel – and run pretty much their entire state budget (and blow money on modern Western weapons) on the profits from it? Short answer: You’re nuts.

      Also, the installed capacity if geothermal is about 0.3% of total US capacity, and we put the existing geothermal plants in the best places for geothermal (aside from the visitor center at Yellowstone), so it won’t be backing up very much. Nor can hydroelectric pumping be of much use because we don’t have high reservoirs to put the water in, and all the lakes in the US (which are extremely large) can only provide 7% of our energy as it is.

    • Rgates

      Instead lets imagine a number of guns lying on a table, each with a bullet in one of the chambers. You have the opportunity to disarm them one at a time before they are levelled at your grandchilds head..

      The CAGW gun has 1,000,000 chambers. The handing down crippling debt gun has 5 chambers. The lack of cheap reliable energy gun has 5 chambers. The physical Terrorist threat has 5 chambers. The cyber terrorist threat gun has 3 chambers.

      There are many other guns with varying numbers of chambers all reflecting different issues, some offering unlikely and highly theoretical risks (CAGW) to very real ones that need to be tackled, and different time scales from ‘NOW!’ to ‘perhaps in 500 years.’.

      Bearing in mind we have limited resources, which guns would you try to disarm first?

      CAGW is so far down my personal list that there wouldn’t even be room for it on the table. Obviously you will think that each gun has a different number of chambers to what I have portrayed and will have your own time scales.

      However, would your personal disarming -based on perceived danger-REALLY start with the CAGW gun?

      tonyb

    • o George Turner | April 20, 2014 at 8:30 pm |

      ..how on Earth do major oil producing states both subsidize fossil fuel – and run pretty much their entire state budget (and blow money on modern Western weapons) on the profits from it?

      To help you out with this, a look from opposite ends of the political spectrum:
      http://priceofoil.org/fossil-fuel-subsidies/international/
      http://www.forbes.com/sites/energysource/2012/04/25/the-surprising-reason-that-oil-subsidies-persist-even-liberals-love-them/

      While there is a wide level of uncertainty in estimates, a diversity of views about the issues, and complexity in the situations, there’s no lack of evidence for the subsidies you are in denial about, applying fallacious argument to pretend isn’t real. Pretty much the whole state budget of oil producing states with no other income gets there from international sources. So what? How does that make it less subsidy?

      Also, the installed capacity if geothermal is about 0.3% of total US capacity, and we put the existing geothermal plants in the best places for geothermal (aside from the visitor center at Yellowstone), so it won’t be backing up very much. Nor can hydroelectric pumping be of much use because we don’t have high reservoirs to put the water in, and all the lakes in the US (which are extremely large) can only provide 7% of our energy as it is.

      You make these claims about geothermal, but they’re simply not true of modern available technology.

      Also, you seem to have the idea backwards: baseline power isn’t the back-up, it’s the mainstay all the other sources provide peak power on top of; a guarantee that the necessary power for the nation is maintained. The back-up is hydro, and the complementary coverage of multiple different energy generation types.

      The same advances that allow fracking to access more natural gas allows geothermal to be tapped. High capacity DC allows electricity to be distributed many times as far AC technology could sustain, so geothermal from Rocky Mountain range volcanoes like Mt. St. Helens could furnish virtually the entire west half of the USA, and solar from the sun belt could furnish easily the southern three quarters of the country, while wind and hydro more than cover all the rest.

      Nor is hydroelectric so limited as you claim, though the Pump Up The Storage post from November, 2011 on Do The Math at Physics.UCSD.EDU points out, there are challenges at first blush when some armchair ‘expert’ with no experience throws around estimates. But the estimates do not well model the actual, as papers like http://ieeexplore.ieee.org/xpl/login.jsp?tp=&arnumber=1294989&url=http%3A%2F%2Fieeexplore.ieee.org%2Fxpls%2Fabs_all.jsp%3Farnumber%3D1294989 show. Studies show 20% to 40% of domestic electricity needs can be supplied by pumped hydro despite your much lower unsupported claims.

      o climatereason | April 21, 2014 at 7:46 am |

      Wait. What?

      You rank risk of harm from climate catastrophe at one in a million; scale crippling debt with similar levels of harm (one presumes) at only one in five, and one presumes none of the crippling debt is from climate causes short of catastrophe, too; somehow construe lack of cheap reliable energy in proportion to this also at 20% likely; physical terror as TWENTY PERCENT likely; and Internet por.. terrorism at OVER THIRTY THREE PERCENT likely to scale to the destructive power of drought, flood, cyclone, heatwave and the sort of jet stream caused lingering polar conditions in we’ve seen in winter across the globe?

      You are, frankly, displaying innumeracy and faulty estimation on a fantastical order of magnitude.

      You’ve inflated physical terrorism by about a millionfold, based on statistics to date.

      You’ve turned Gibsonian science fiction into an existential threat to the real world without batting an eyelash.

      You’ve ignored the far largely likelihood of economic harm even the likes of Richard Tol admit from AGW (though Tol doesn’t see it getting that bad for 10% of your 500 year timescale, he does write about it as a five chambers of five proposition).

      If your descendants must rely on your math skills for their survival, *BANG* they’re dead; or worse, they’re poor.

    • BartR

      The one in a million is intended to put over that, to me, CAGW is highly unlikely and ranks far below other perceived threats. It was slightly tongue in cheek as it was aimed at RGates who is able to differentiate between tongue in cheek comments and ones meant literally. Had I addressed it to you it would have been framed differently.

      Others would have other concerns and put them in a different order of ranking, which is precisely why I expressed it in that manner so other people could put their own odds in.

      As far as debt goes, yes, the money we are spending on dealing with imaginary hobgoblins is likely to add to our debt burden, you might see it in another manner.

      So how about putting YOUR odds on the table? What threats do you perceive and how do they rank? Is CAGW REALLY up there at the top of your concerns?

      tonyb

    • climatereason | April 21, 2014 at 11:36 am |

      Oh. I get it. You meant to misstate your probabilities by orders of magnitude as a joke. No, really, officer, I was only swerving all over the road to kid with my passengers, who get my sense of humor.

      You cherry picked with your tongue firmly in cheek, but only for RGates, and not for the rest of us, who you now readily agree your figures were not just framed differently but completely wrongly?

      No, you don’t. You’re rationalizing, and not particularly well.

      I don’t for a second suggest your politicians are spending your tax dollars terribly well. Perhaps it’s lead in the pipes or too much socialism, or an upbringing in an inferior educational system, that makes your politicians such terrible money managers. I don’t know, and as I’m not living in your country, don’t care to become embroiled in debates that should happen in your democracy among your people, without foreign interjection.

      But to blame bad money decisions by politicians on scientific fact, while presenting some of the most overblown innumeracy I’ve ever seen outside of Star Trek, just does not inspire much confidence that democracy will soon fix what’s wrong with your government, if you are representative of the logic brought to political debate on your side of the Atlantic.

    • climatereason | April 21, 2014 at 11:36 am |

      Threats don’t much interest me. My money interests me. What is mine interests me. I have a share in the rivalrous, excludable, administrable, scarce CO2E-absorbing resource of my nation’s air. It turns out, that resource is quite valuable, worth two and a half times the entire fossil fuel industry. Well, I want my split of that, as air is an unalienable private resource: just try to stop breathing, and see how long you last without it.

      Shaun Lovejoy has shown to 99% confidence that AGW is caused by CO2E emissions. That’s 99 bullets in 100 chambers, and we don’t know what’s in the 100th chamber, aimed directly at my wallet.

      Catastrophe? The arguments for that take up less than one percent of the IPCC reports. The arguments for damage to my wallet take up many times that space. Why do you ignore my wallet, and focus only on your dying grandchildren?

      What are your grandchildren’s lives to me, when my wallet is harmed — and even Tol agrees — more by AGW than by mitigation, in the long run?

      • @bart

        Shaun Lovejoy has shown to 99% confidence that AGW is caused by CO2E emissions. That’s 99 bullets in 100 chambers, and we don’t know what’s in the 100th chamber, aimed directly at my wallet.

        Actually, no. It shows no such thing. It merely shows that it has a gun in the game. Not that it was lethal (had any bullets).

    • Fossil fuel subsidies on a per kwH basis are tiny compared to solar and wind as anyone can verify for himself. I’ve cited the Energy Information Administration and the work of Severin Borenstein on the relative costs of solar energy compared to fossil fuels. There are lots of other data sources out there, but the evidence from Spain and Germany, where even small cutbacks in these subsidies are leading to a crisis in the solar industry, should suffice. Arguments to the contrary are like arguing that the sky isn’t blue in Denver. The laughable suggestion that geothermal energy could replace fossil fuels in generating electricity in the United States pretty ought to place Bart’s credibility in perspective.

    • stevepostrel | April 21, 2014 at 9:00 pm |

      What an interestingly cherrypicked basis. Per historical kWh that’s happened in the past.

      Not that I’m a supporter of subsidies of any stripe, so could simply say get rid of all the subsidies, but let’s not let innumeracy rule even one more line of this discourse: worldwide subsidies on carbon burning energy are so large, and form such a barrier to entry to the energy market of alternatives, as to beggar the fractions of pennies spent on alternatives except nuclear by comparison.

      Meanwhile, while I don’t think it’s a very attractive argument, as it opens the slippery slope of somehow believing any good might come of subsidy, the improvements in output per dollar for solar during this brief infant industry moment coinciding with subsidies have been exponential, and are expected to continue to be so, even if all subsidies for solar ended tomorrow.

      What would happen to carbon burning if government subsidies halted overnight?

    • And since there’s so much rehashing of Borenstein’s at-the-time-criticized-as-obsolete paper about residential installation from six years ago based on installed costs from four years before that (that is, when the price of solar was some FIVE times what it is today for CSPV farms, my topic), let’s see what Borenstein has to say about it.

      http://faculty.haas.berkeley.edu/borenste/SolarResponse.pdf

      The paper is an economic analysis of the current solar PV technology that is being installed in homes and small commercial establishments today. It is not an analysis of the what might happen 3, 5 or 20 years from now.

      – Borenstein, 2009, about Borenstein’s use of 2004 figures

      Borenstein’s comparisons included comparisons to solar thermal farms of the time. Citing Borenstein does not address my case for CSPV, nor support a case for fossil.

      Borenstein hasn’t written a new paper on this subject in three years, and his analyses are typically based on information much earlier than his publication date, which is unsurprising given the slowness of peer review. If you want to know what Borenstein will have to say about decisions made today on stationary power, at this rate you’ll have to wait until 2024.

    • BartR

      Your logic is deserting you. Surely a slightly tongue in cheek comment addressed directly to someone who would appreciate the analogy in the spirit intended, is going to be different to one directly aimed at those people who like to deconstruct every word and find a meaning to suit their purposes?

      tonyb

  20. Jeff Melcher

    Hi Mr Appell,

    You write: “There is never going to be complete knowledge of the future climate system. The question then, is how you make decisions in light of imperfect knowledge? ..[O]r you make a decision to do nothing, when in fact we don’t do that in other areas of our individual or societal lives.

    First of all, individually we don’t all have to make the same decision. I might choose to worry about asteroid strikes (for the planet) and fire (for my home and family) while you choose to worry about climate and burglars. This is “Business as Usual”. Why change that for your obsession rather than mine?

    Secondly, of course we can decide to do “nothing” — in the sense that we DO do something, else. There is necessarily only so much time and attention and money and talent to apply to any concern. You seem to think that because you worry about — for instance, let’s assume — burglars that you and I and everybody else must DO something about burglars. Well, maybe we will regret the choice but some of us would rather hire more fire fighters than more cops. That’s why we vote, (f “we” must choose collectively) or buy insurance and various home insurance riders, etc. (if we distribute our individual resources as we individually prefer.) It’s not doing “nothing” to do something ELSE, or if it is every one of us does a lot more nothing that something every single day. In economics there is a concept of “opportunity costing” for the second-most preferred option. We can’t sum up ALL the risks of all the risks, we MUST (per this method) compare the risks we most worry about with the one other risk we next-most worry about.

    By the way, I do come by and comment periodically. I don’t want your blogging effort to get too discouraged from low traffic. Carry on, you’re providing a public service.

    • k scott denison

      +1

      I grow very weary of those who insist I do “something” about their fears and as you say, don’t recognize that my priorities might be different.

      By all means, do your best to convince me to change my mind with data. But if all you have are models and scary scenarios, well, I’ll stick with my own priorities thank you.

    • Turning sunk the Titanic. And here in Michigan, we have a campaign “don’t veer for deer!” Do nothing is often safer in the novel situations that technology and developed society provide. Global warming is probably among the type of situation that the biases of our evolved “fight or flight” response don’t apply to well.

    • True, the AGW alarmists have set psychology back so far that children hiding under blankets in the dark, afraid of a thunderstorm, is called exercising reason–e.g., I think therefore I think I am worried… about global warming.

  21. Political Junkie

    Paul Woland,

    We don’t insure against all risks. Even in the case of home insurance if the benefits won’t allow me to replace my home or if the premiums exceed the value of the property, I wouldn’t insure.

    Paying a certain known cost to deal with uncertain risks and unknowable benefits is not a logical proposition.

    • Political Junkie | April 18, 2014 at 1:04 pm |

      Paying any cost at all to deal with any uncertainty or risk or future benefit is not a ‘logical’ stragety, though it is a rational one.

      There are many forms of reasoning, logic is only one of them; where logic is not in command (which is most of the time for most of the population), the decision is a private one of risk tolerance or uncertainty tolerance. Those who prefer risk may enjoy more of the benefits of the gamble, and must endure more of the downside of the losses. Those who tolerate uncertainty more will discover more, or may discover nothing but grief.

      But deciding for others what risks, perils and uncertainties they must tolerate for your own private benefit? That’s simple tyranny.

    • k scott denison

      And Bart, the opposite is also tyranny:

      “Deciding for others what risks, perils and uncertainties they must NOT tolerate for your own private benefit.” Like climate alarmism and mitigation.

    • k scott denison | April 18, 2014 at 2:20 pm |

      Lucky for others, I only want them to decide for themselves what risks and uncertainties they’ll tolerate. I merely want them to also be paid by people who want to expose them to higher levels to pay them fair compensation.

      That’s not tyranny. That’s the democracy of Market capitalism.

    • Bart R | April 18, 2014 at 8:10 pm | ” I merely want them to also be paid by people who want to expose them to higher levels to pay them fair compensation.”

      Where “fair compensation” is determined by an unelected minority and the distribution of the proceeds thereof benefits the wealthy,

    • RobertInAz | April 18, 2014 at 11:05 pm |

      Uh, no.

      I want the Market to determine the price by the Law of Supply and Demand, with no one controlling it, and no one getting an unequal share.

      Heck, I don’t even want the government involved, except for the part where it investigates thefts and throws thieves in prison.

      There’s no reason private individuals and organizations couldn’t do as, for example, those ‘Certified Organic’ people do, and put ‘Certified CO2E Paid’ on CO2E sourced products and services for a fee, and then send dividends out to the members who refuse to buy anything without the certificate.

  22. Climate may be the most benign of all *risk* considered of global importance today.

    If we have another repeat of Sept ’09, add in some influence from Chinese/Intl investors, it could ruin just about eveyone’s life. The impact would be felt within a month and within a year almost everyone’s plans will have been dramatically altered. This blog might not even exist.

    OK, let’s say 2017 is a super El-nino: GMT +0.3C and holding – unprecedented! The AGW signal is back. Within a month, some fishermen are out of business. Within a year, crop futures are up 10%? And, we’re back to seeing a likely ECS for 2100 >3C, and that’s just eight decades away.

    The point is, extreme tail value at 2100 arrives only if a detectable signal arrives in the medium term. But a detectable signal isn’t impactful at all (compared to almost any other risk we plan for, like war, or economic collapse). Then when we finally see the signal, we have literally generations to absorb any damages, adjust, or mitigate further emissions.

    • SUT | April 18, 2014 at 1:04 pm |

      How does this extreme tail value at 2100 arrive “only” if a detectable signal arrives in the medium term?

      Detectable beyond the detectable signals we’ve been seeing for the past century?

      You sound like you’re saying you won’t believe any signal until after 2100.. and even if you might be moved by some single weather event — remembering that weather is not the same as climate — many will not be.

      But let’s give you the credit of buying that you might be willing to abandon your foregone conclusion presented adequate evidence rationally.. (even though so far that has failed to move your mind)

      Why ought a detectable signal be necessary for an extreme tail value at 2100?

      Nature loves a sigmoid, and Black Swans often presage shifts in the opposite direction. We could have a year without Summer as the globe’s kickoff into a large and sustained leap in temperatures, or a gradual move into an exponential temperature growth rate starting extremely slowly for decades, and both of those scenarios are precedented and realistic; neither equipartition nor warning shot across the bows by some Nature spirit is.

    • *Alarming* signal detection: temperature (actual, as it is realized) to be inside the forecast cone for those climate model ensembles that arrive at CAGW a hundred years later. Actual – Predicted discrepancy is too large currently.

      detection of *non-zero* trend: I think we’ve found it already.

      The CO2 forcing is interesting because: A. it’s significant (multiple W/m2 TOA), B. rapid compared with other forcings, like Milkanovitch. C inexorably increasing through the (economic) medium term, making it an easy variable to forecast, unlike say Volcanoes.

      From these properties, and from Paleo evidence to other types of forcings, I don’t see the dragon kings being summoned here in the 20 – 50 years period following an alarming signal detection (across most regions). My point is not that CAGW can’t happen, or won’t be harmful, but having decades of response time is a luxury unparalleled in human concerns. Contrast to say a significant share of the population can’t pay next month’s mortgage, which is plausible given the highly connected modern financial system, and it’s potential for internal feedback.

    • sut | April 18, 2014 at 2:56 pm |

      Forecast freaking cone?

      (a.) GCM’s do not forecast. They process formulae based on initial conditions. Their output is not a prediction of actual outcomes.

      (b.) GCM ensembles are worse than any one GCM if treated as part of a PDF and the logic of Statistics is applied to them.

      (c.) Comparisons of anything to ensembles also do not form predictions, nor do they disprove the accuracy of the GCMs or their underlying Science.

      (d.) GCMs are run at a resolution many many times too coarse to ever even be useful for prediction, even if all initial conditions could be precisely known; the influence of even the smallest factor outside the model, from solar to industrial to volcano, could propagate over generations to rapidly disrupt the course of the climate.

      Your logic is simply based on bad understanding of GCMs. There is no meaningful freaking forecast cone. Figures falling outside some imaginary range mean nothing to the Earth energy balance. From my own point of view, I simplify to the thermomechanical principal: half of the warming must translate into other forms of energy than heat, including forms that change the structure of the climate system, leading to radical new extremes of weather under the newly formed climate regime.

      We might have decades. Or the change may already have begun undetected. We don’t have luxury. We have uncertainty, and anyone expressing certainty of decades is certainly irrational.

    • “Or the change may already have begun undetected.”
      _____
      But of course the “change” has already been detected in many parts of the system. Just the growth of methane alone cannot continue without an increasing potential for catastrophic consequences for human civilization That trend alone is one that must be reversed. The AMEG group may be wildly alarmist, but it is not beyond all possibility that they are correct.

  23. In the short term all bets are off because there has not been any warming now for 18 years with C02 rising.To assume that there was warming previously (30 years or so) due to AGW is also a guess due to “constant temperature adjustments” by interested parties. The whole thing is appearing to be a complete farce and my guess is that no one knows at this stage if C02 has had ANY effect of mean global temperatures over the past 60 years or so…My guess is that it has not (refer to LIndzen’s negative feedback paper). There is no doubt that in a laboratory environment (arrhenius) the AGW hypothesis is true but not on the living earth where it may be in fact MORE negative, if anything.

  24. AmateurSkeptic

    I think this point she made needs to be constantly emphasized to the public: “a possibility that has not been articulated might come true. These possibilities (e.g. abrupt climate change) are associated with natural climate variability”.

    The argument among alarmists often seems to be that action is needed “just in case”, as with insurance. It seems possible (even if unlikely) that humans are having an impact on climate, and that impact is preventing us from slipping into another ice age. Perhaps the odds of that are very low, but they aren’t really known, just as with the usual alarmist case. However this alarmist case in the opposite direction would argue that we not reduce emissions. Some of us are skeptical that we have anything close enough to a good model of potential long term natural climate variation trends (even aside from skepticism of short term model realism) and so it doesn’t seem we don’t have a good sense of the true probabilities distribution of future climate behavior. I’m skeptic of her implication of some certainty of a “lower bound” without far better validation of models against reality in ways that don’t seem like a joke to those from other fields.

    e.g. models indirectly (via learning from past models and tests) and directly wind up tweaked based on the whole historical record despite any efforts to supposedly separate out part of the trend to be used to validate predictions based on the rest of the data, they have different physics in different models yet are tweaked to give similar results undermining any credibility that a physically motivated model should be granted above what mere curve fitting argues for (which isn’t much), etc.

    • George Turner

      I think a balanced assessment of climate risks must include a renewed glaciation period, and given past climate history, orbital mechanics, and all the other knowns, I would describe the likelihood that we don’t slip into glaciation at some point in the future as extremely unlikely – but possible.

      Then I would look at the impacts of glaciation, which are more severe to civilization (pull up an old map of glacial extent and write off anything in the white area) than almost anything conceivable from a 3C rise in temperatures (the Eemian was a time of living high). For the Earth’s current inhabitants to survive such a glaciation with current population levels will require extensive use of intensive agriculture, energy, and technology, along with drastic and highly disruptive relocations..

      In the longer term, catastrophic glaciation surely rates as more likely (likelihood approaching one) than some of the bizarre hypothetical scenarios bandied about.

    • George Turner | April 18, 2014 at 2:11 pm |

      And in 20,000 to 30,000 years, it might be your idea’s turn to be an issue.

      Until then, it simply isn’t.

      However, _right_ now, today, the issue at hand deals with probabilities that our best estimates place some ten orders of magnitude more likely than your immaterial attempt at minimization. Maybe you shouldn’t go around saying absurd things until you can tell the difference.

    • George Turner, “I think a balanced assessment of climate risks must include a renewed glaciation period, ”

      Not really, man is pretty good at snow/ice removal and has been for some time.

    • Actually, triggering an ice age early is one of the catastrophes people believe plausible. And I think it is, but not in time frame reasonable for policy. The mechanism aren’t there for a quick and sudden ice age trigger. But, imagine for a moment that inter-glacial energy budgets are not in equilibrium, that a significant amount of energy goes to the deep ocean. When the ocean warms enough, mixing with surface heat decreases and surface warming increases. The increased surface warming eventually leads to more snow and clouds and the energy budget changes sign, with a smaller magnitude, and that accumulated energy is very slowly radiated away until something triggers surface warming again.

    • aaron,

      a cool period, similar to a little ice age, may be possible, but a real glacial period requires land to store lots and lots of ice. A lot of the land used for ice storage in previous glacial periods is now farmland which is not difficult to de-ice. So a lot of the downside is improbable due to anthropogenic methods of warming. A major glacial really cannot get a foot hold with a catastrophic event such as mega volcano or impact. That is a part of the fat tail, but not considered since everything is CO2 centered.

    • George Turner

      Man is not at all good at snow and ice removal past a certain point, easily reached in major storm sequences, when we run out of convenient places to pile it. If the snow piles don’t melt in the summer to give removal efforts a reset, it’s game over. As far as I’m aware, we have never tried removing hundreds of feet of snow from anywhere, much less everywhere.

    • George Turner, “Man is not at all good at snow and ice removal past a certain point, ..”

      That point is determined by economics. You would be amazed how much snow you can melt with a tractor and spreader.

    • George Turner | April 18, 2014 at 6:03 pm |

      I have pals who clear many hundreds of feet of snow and ice at a time in avalanche prevention. You can modify a lot of structure with selective use of explosive force.

      More to the point, above 230 ppmv, the radiation energy balance prediction of mainstream physics is that global glaciation cannot happen, at least not while the Earth maintains its current tilt or pending a century of particulate-saturated stratosphere. We’re in no danger of going below 230 ppmv any time soon. If you know a way to tilt the Earth prematurely, be my guest, I know how to ski. But I find sulfates make my complexion look washed out, so please don’t start pumping those above the tropopause.

      Whatever way you have it, you’re not presenting a balanced option, you’re being absurd under an equal time argument out of pique.

    • George Turner

      Bart, the avalanche removal techniques work great if your city is bolted to the side of a mountain, but in flat lands, where almost all of our cities are, it doesn’t apply. The Earth has gone into ice ages with CO2 running above 4000 ppm, so the 230 ppm is just a conjured number.

      I also find it amusing that alarmists who preach doom about the costs of an extra two or three degrees of warmth, and that mankind will be unable to cope with the costs, assume everybody is going to have unlimited fuel, salt, heavy equipment, and explosives to cope with renewed glaciation, as if all that is just free because science!

    • Having spent my youth working farms, I would never underestimate the ability of farmers to prepare their land for planting. It will not be snow cover, it will be temperature. And in North America – the farmers will beat the snow until temperature dominates.

    • George Turner

      Robert, crops don’t really grow well in snow. Note the lack of crops being grown in northern Canada.

    • George Turner | April 18, 2014 at 11:45 pm |

      You are mistaken in a number of ways.

      1. Much of Canada is barren tundra, and sees so little snow or other precipitation as to remain virtually uncovered for decades on end, yet no one farms there, either. That’s to do with temperature and light levels, not snow cover.

      2. Quebec, in Canada, has many farms where farmers have historically tilled over snow and ice covered with hay, compost and soil. The same technique (more or less) has also been recorded in Poland some centuries ago. It’s possible to farm on snow. It’s just not as easy. Go ahead, ask a farmer sometime about the phrase “easy farming”.

      3. You’re citing an argument put forward by Ian Plimer about the 4000 ppmv glaciation. Let’s have a look at that: http://www.skepticalscience.com/co2-higher-in-past.htm shows the speculative counterarguments:

      Plimer’s stated value of 4000 ppmv or greater is taken from Robert Berner’s GEOCARB, a well-known geochemical model of ancient CO2. As the Ordovician was so long ago, there are huge uncertainties for that time period (according to the model, CO2 was between an incredible 2400 and 9000 ppmv.) Crucially, GEOCARB has a 10 million year timestep, leading Berner to explicitly advise against using his model to estimate Late Ordovician CO2 levels due its inability to account for short-term CO2 fluctuations. He noted that “exact values of CO2… should not be taken literally.”

      What about evidence for any of these short-term CO2 fluctuations? Recent research has uncovered evidence for lower ocean temperatures during the Ordovician than previously thought, creating ideal conditions for a huge spurt in marine biodiversity and correspondingly large drawdown of CO2 from the atmosphere through carbon burial in the ocean. A period of mountain-building was also underway (the so-called Taconic orogeny) increasing the amount of rock weathering taking place and subsequently lowering CO2 levels even further. The evidence is definitely there for a short-term disruption of the carbon cycle.

      Another important factor is the sun. During the Ordovician, it would have been several percent dimmer according to established nuclear models of main sequence stars. Surprisingly, this raises the CO2 threshold for glaciation to a staggering 3000 ppmv or so. This also explains (along with the logarithmic forcing effect of CO2) why a runaway greenhouse didn’t occur: with a dimmer sun, high CO2 is necessary to stop the Earth freezing over.

      In summary, we know CO2 was probably very high coming into the Late Ordovician period, however the subsequent dip in CO2 was brief enough not to register in the GEOCARB model, yet low enough (with the help of a dimmer sun) to trigger permanent ice-formation. Effectively it was a brief excursion to coldness during an otherwise warm era, due to a coincidence of conditions.

      So what is more plausible? That radiative transfer Physics equations are off by an order of magnitude for mysterious and never-to-be-revealed causes and everything about the Earth has remained more or less equal for 444 million years, or the observations with a resolution of 10 million years taken from geological extrapolations may have been overstated for some period of perhaps a hundred thousand years during which a significantly dimmer Sun (by more than 100 times the variation we see in solar output in modern times) allowed glaciation?

      In the case Plimer argues, we’d have to assume stassis, equipartition, removed uncertainty, precision one hundred times or more greater than the instrumental observations allow, and some unknown compensator for the dim of the Sun so long ago. We’d have to find some reason to exempt every glaciation we do have high resolution geological (and even fossil) data for, as exceptions to the rule set by Plimer’s one single glacier on those shakey assumptions, and we’d have to allow Plimer’s one singleton to rule the more universally applicable model while ignoring how shakey its assumptions. In other words, NOT SCIENCE.

      4. Again, “renewed glaciation” remains a negligible probability for the next 20,000-30,000 years; including it in our considerations at this time can be done on that basis, most especially if some reckless party argues for geoengineering solutions that overdim the planet, but what’s the benefit?

      All you’re doing is obscuring the clearest cases with the less clear cases, apparently out of spite. Sure, we could include your case, but we’d also have to allow for unicorns and leprechauns if we did. We could go too far the other direction, too, and ignore the unlikeliest of the non-negligible catastrophic cases, but as they are more likely than all the cases proposed by people who claim benefits of AGW or of high CO2E, we’d again have to dismiss anything but harm from AGW.

      Any universe of argument which lets us waste our time listening to Tol’s claptrap requires us to give more time to end-of-all-life, as Tolish outcomes remain less likely than existential threats, and neither of them is the very interesting part of the continuum of likely outcomes.

      The interesting part is the part where people stop stealing CO2E emission share from me.

    • George Turner

      Bart, your sources seem to completely neglect that CO2 gives diminishing returns. Once the narrow IR bands affected by CO2 are saturated, further increases in CO2 would have no effect. See MODTRAN.

      Also, the current Holocene warm period has lasted about 11,700 years. Previous interglacials lasted about 10 to 15,000 years. We’re not going to have to wait 20 or 30,000 years to see the return of the giant glaciers.

    • George Turner | April 20, 2014 at 4:58 pm |

      IR bands in CO2 are noted for their broadening power, in particular in air. http://www.nrcresearchpress.com/doi/abs/10.1139/p72-353#.U1VEej9OXcs discusses this phenomenon. In effect, CO2 bands are nonperishing, and while there is a logarithmic relationship it is a very low logarithmic effect at present concentrations.

      You’re simply exaggerating a real effect not likely to have any impact. Which sounds familiar.

      http://www.sciencedirect.com/science/article/pii/S0033589497919189

      The evidence suggests 15-26 thousand years for the duration of interglacial periods. Maybe you have a source you can cite with observations and inference that shortens this range by 50% to 90%?

  25. I would also like to point out that climate changes that matter most to society and the environment are those in which the statistics (e.g. frequency of occurrence, detailed structure, intensity, etc) of major atmospheric and ocean circulation features such as ENSO, the NAO, PDO etc change over time. In the 2005 NRC report [whose conclusions have been ignored by the IPCC]

    National Research Council, 2005: Radiative forcing of climate change: Expanding the concept and addressing uncertainties. Committee on Radiative Forcing Effects on Climate Change, Climate Research Committee, Board on Atmospheric Sciences and Climate, Division on Earth and Life Studies, The National Academies Press, Washington, D.C., 208 pp. http://www.nap.edu/openbook/0309095069/html/

    it was concluded in that

    “Regional variations in radiative forcing may have important regional and global climatic implications that are not resolved by the concept of global mean radiative forcing…..regional forcings can lead to global climate responses, while global forcings can be associated with regional climate responses. Regional diabatic heating can also cause atmospheric teleconnections that influence regional climate thousands of kilometers away from the point of forcing.”

    The global annual average temperature anomaly is a grossly inadequate metric to actually quantify climate risks. Thus focusing on a global annual average anomaly of +1C, +5C, or even -1C, misses what should be the greater concern.

    This greater concern involves those climate features that have the largest impact on society and the environment. This includes drought, floods, late spring freezes, sea ice melt season, etc, all of which are regional issues which are strongly influenced by regional atmospheric and ocean circulation patterns. This is the much more important “climate sensitivity”.

    Roger Sr.

  26. The very strong El Nino of 1997 had a profound effect on warmistas (I was one). It was a one off fluke and a lot of AGW nonsense was based on that one year.

    • 1998 isn’t even the warmest year on record. 2005 beat it. Then 2010. It’s more than a fluke, it’s manmade global warming. Take note.

    • Alexej Buergin

      According to RSS 1998 (the effects of the El Niño 1997-1998) was the warmest year of the satellite record:
      http://www.woodfortrees.org/plot/rss/from:1996/plot/rss/from:1996.58/trend

    • Alexej Buergin | April 18, 2014 at 4:13 pm |

      You know RSS is derived from a leaky, malfunctioning satellite’s transmissions, closely held by a small group of zealous partisans, right?

      The point isn’t which year’s been hottest. The point is, 1998 was only a fluke in 1998. It’s been more or less routine since.

    • Alexej Buergin

      Bart R:
      The point is that I answered lolwot who said that 1998 is not the warmest year on record.
      And your description of how todays NASA works is if not amusing, then quite sad.

    • Alexej Buergin | April 19, 2014 at 3:30 pm |

      RSS is not the same as NASA.

      The story of RSS is much more nuanced than I implied, and I’m sure the nice people there can attest to that. http://www.remss.com/about/who-we-are

      However, the story of 1998 compared to 2005 is very straightforward.

      Comparisons of surface air temperature alone might show 1998 and 2005 approximately on par, depending on various factors and considerations, depending if you count only the single years or the averages to smooth out short term factors. However, if you consider Cowtan and Way, or count the changes in the Arctic and Antarctic, deep sea and thermomechanics of the atmosphere, there’s no doubt 2005 was warmer than 1998.

      http://nsidc.org/arcticseaicenews/charctic-interactive-sea-ice-graph/

      ftp://ftp.nodc.noaa.gov/pub/data.nodc/woa/PUBLICATIONS/grlheat08.pdf

      And it’s still not the point.

      The point remains, the global temperature of the past 16 years is dramatically warmer, and consistently so, than the global temperature of the two centuries before, and we know from Marcott et al, likely as high as we’ve seen in the Holocene to date, and getting higher every year, whether El Nino or La Nina, regardless of ocean oscillations or solar changes we would normally expect would ‘naturally’ vary the global temperature into a steep plunge, regardless of volcano activity that statistically shift the probability toward cold but just did not chill the fever level.

      A normal ENSO, if ENSO was the only factor, should have seen the globe return to cooler temperatures within three years at most. A normal natural global temperature curve ought have plunged to pre-1970’s levels on solar and ocean oscillations. The stadium wave ought have had the temperatures sitting down. They’re standing up, standing on their seats, standing on top of the shoulders of their neighbors, and jumping. On stilts. With pogo sticks.

    • Alexej Buergin

      Of course there is also UAH, and guess what, they have 1998 as the warmest year, too.
      What a pity the Russians do not measure the temperature of the lower troposphere with satellites; they would do it properly. Or maybe they just do not want to tell us.

    • Alexej Buergin | April 19, 2014 at 8:26 pm |

      If you’d followed the RSS link, you’d have discovered that UAH and RSS draw down the same MSU satellite data, with the same leak, and the same imprecision. Except UAH is run by fundamentalists who don’t like admitting AGW is real, while RSS is run by investors who don’t like admitting their satellite is broken.

      Their weather reports are fine, for a day or a month at a time. Over periods much longer than a year, they’re severely compromised.

      I’ve been reading the Russian climate literature, with some embarrassment over what passes for intellectualism these days there.

      And again, none of this is the point. 1998 was last a global temperature fluke in 1998. Since then, it’s been routine.

    • Alexej Buergin

      According to Spencer UAH uses 4 different satellites at the moment:
      http://www.drroyspencer.com/latest-global-temperatures/

    • Alexej Buergin

      Like it or not, Spencer says there is AGW:
      http://www.catholic.org/news/green/story.php?id=50654

      whereas you use Bart’s temperature trick to hide the decline.

    • Alexej Buergin | April 20, 2014 at 10:48 am |

      I will say to you what I say to all who hurl links around as if expecting me to click on them: you need to provide me a better reason than appeal to authority to drill down to your level.

      I’m not in the least interested in what Dr. Spencer has to say about the satellites he uses, as _one_ of them is known to be broken, and was the main source of his data — broken — for most of the history of the UAH dataset, without Spencer once either catching onto the problem, or admitting it after others found it, or opening up his input data or code for inspection or sharing.

      The same thinking that got Spencer into the UAH mess with one satellite isn’t credible to get UAH out of the mess now with four satellites.

      Why we don’t have forty or four hundred satellites with open datastreams for something as valuable as weather and climate data, and so much more that could be gotten out of them, indicates a serious failure of decision power. Somewhere, somehow, we have allowed bad management to squander our orbital resources at great cost to us all.

    • George Turner

      Preach it Bart.

      To the people who control the climate change purse strings, good unimpeachable data is like holy water to a vampire. God forbid we had accurate measurements instead of weather stations positioned between a pair of runways where the Boeings rev their engines. No heat contamination there. No Sir Ree.Bob.

      Somehow, the lack of uncontaminated data is due to the Koch Brothers. Yes indeedy.

  27. Eliza | April 18, 2014 at 1:17 pm |

    Can you tell us how many years since 1997 the globe has been cooler than 1997?

    Here, let me help you out:

    http://www.woodfortrees.org/plot/hadcrut4gl/mean:5/mean:7/from:1997/plot/hadcrut4gl/from:1997/trend

    Considering that even the deepest La Nina of the past 15 years has been warmer than 1997, even with volcano particulates in the stratosphere from seventeen high-altitude plumes — a record in the volcano record — and solar changes that have had zero perceptible TOA impact either way.. if the El Nino were the only fluke to have a profound effect, that would be remarkable.

    • Nice cherry picking.

      How many of the years have been warmer than 1998. using only unadjusted readings?

    • philjourdan | April 18, 2014 at 1:54 pm |

      You really don’t know how global temperatures are collected, to you?

      There are no ‘readings’ that directly deliver the level of global warmth. Every figure in every table is derived from an adjusted figure derived from an adjusted figure several times removed.

      Making a ballyhoo over ‘adjustment’ without reason is specious.

      Sure, in the case where adjustments are arbitrary and incompetent, done solely to manufacture a result, as in the case of Roy Spencer’s UHI adjustment of CONUS temperatures, that’s an issue. But unless you can demonstrate something like the level of problems with Spencer’s order of magnitude, wrong direction, and lack of accounting for changing conditions underlying his formula, you’re just mouthing empty words.

      • @bart – I will hand you a partial one on that. Readings is not a good word in that sense. I know full well how the temperature is derived/massaged. However your dismissal of the report http://agbjarn.blog.is/blog/agbjarn/entry/1375663/

        Without apparently reading it, indicates you have no clue what you are talking about.

        Sorry for the misuse of the word “reading”. “Calculated levels using UNADJUSTED temperature data”. More wordy, but more precise.

    • http://www.woodfortrees.org/plot/hadcrut3gl/mean:23/mean:25/from:1997

      However, since you ask nicely, six of the years from the unadjusted, deprecated HADCRU3 dataset on a floating four year average have been warmer than 1998.

      I’m sure I don’t need to explain the confidence interval of that claim to you.

    • k scott denison

      Here Bart, I fixed it for you:

      http://www.woodfortrees.org/plot/hadcrut3gl/mean:12/mean:14/from:1990

      EVERY year since 1998 has been cooler.

      Fun with data!

    • k scott denison | April 18, 2014 at 2:26 pm |

      I don’t know quite how to break this to you, but you seem to be a bit slow on getting the joke.

      Both no years, and six years, since 1998 have been warmer than 1998 on the ‘unadjusted’ (sheesh, what a malarky term) HADCRU3 dataset. There are other answers, too, depending how you frame them to that poorly-framed question.

      The point remains, Eliza’s claim of fluke is false.

    • philjourdan | April 18, 2014 at 2:55 pm |

      Interesting fictional supposition that something that was never an issue I’ve read, nor even mentioned, has somehow been dismissed.

      What is wrong with the way your brain works? Are you projecting? Imagining conversations that never happened? Think I’m someone else from somewhere else where you’ve had other exchanges? Delusion? Psychoses? Hallucination? What?

      Oh, here it is, it’s just a failure to READ HARDER and stay on the same page.

      If you want me to participate in a thread on another topic, at least point to the topic and the thread. Making people wade through comments with obscure non sequitur will not endear you to them.

      (For those who care, apparently this has something to do with http://judithcurry.com/2014/04/17/climate-change-what-we-dont-know/#comment-525875).

      And again, we should be concerned that some foreigner has a problem reading a NASA web page, why?

      • @bart – you should remember where and when you commented. The article I linked to first talked about the difficulty in retrieving data from the web page, THEN talked about the temperature adjustments that were made to the readings in Iceland. Adjustments that were unexplained.

        Your dismissive comment about “modernizing” a web page showed you did not read the link.

        My mind works fine. Perhaps you need to revisit your comment.

    • “ven with volcano particulates in the stratosphere from seventeen high-altitude plumes — a record in the volcano record — and solar changes that have had zero perceptible”

      The amount of aerosols in the atmosphere over the last 15 years or so has be LOWER than average, see Sato’s work.

      http://data.giss.nasa.gov/modelforce/strataer/

      Now I know that your people are scrambling to make tiny volcanoes the cause of the pause, but that ship has sailed, sunk, been salvaged and made into razor-blades already.

      You will have to try something else to rescue your postulate.

    • philjourdan | April 18, 2014 at 4:51 pm |

      It’d be funny if I remembered something that hadn’t happened. You’re citing something posted in an entirely different comment. I don’t make a habit of drinking from the firehose of poisonous propaganda deeply and widely; I’ll often skip the most obscure and overbuttered passages.

      Of what interest to me is the bad math of the world’s worst bankers? Why should I care about some trivial reading comprehension issue speakers of one of the least comprehensible gibberish dialects on the planet have with NASA instructions? Why drag me into that?

      DocMartyn | April 18, 2014 at 6:46 pm |

      My people? I have people? Pfft. Conspiracy nut much?

      It’s well-known the volcano aerosol relationship is complex, if it’s there at all.. but if anything, it’s sure as heck not a contributor to warming in the half decade following the volcano. As to it being disproven, that’s not at all clear. Hey, did you know Ebola’s absolutely not contagious? There’s plenty of data to prove that. Except for all the data that proves it is.

      • @bart – Again: you should remember where and when you commented.

        Life is not a series of vignettes, but a running tapestry. Perhaps you should not be so quick to condemn, without reading the entire subject of your condemnation first.

    • There is a very high probability that the majority of the years of the 21st Century will turn out to be warmer than 1998.

    • http://www.woodfortrees.org/plot/hadcrut4gl/mean:29/mean:31/from:1995/plot/hadcrut4gl/last:204/trend

      Since 1998, all but three years on a running 5 year period have been warmer than the peak of the running 5 year period including 1998, which shows a rising 17-year trend.

      And that’s only counting the 84% of the surface easiest to measure. Cowtan and Way have shown the rest of the globe is likely warming far faster, on average; deep ocean measures show it too warming in that period; Arctic sea ice mass measures and GRACE Greenland and Antarctic continental ice measures show those too to be reflecting warming by ice loss.

      Anyone claiming a Pause is a counterfeit, if they make no effort to point out these facts.

  28. All this talk of probability is making my brain hurt, how can that have any credibility for such a complex beast as the climate? How about doing nothing for 15 years and see what climate science says then?

    • Mikky | April 18, 2014 at 1:35 pm |

      You mean, emit not CO2E for 15 years?

      I don’t think industry would go for that.

    • Sorry, I meant business as usual for 15 years, though no doubt there will have to be some token action to appease the Green Gods, and prevent Green Zombie Apocalypse.

    • Mikky | April 19, 2014 at 2:03 pm |

      If by “business as usual” you mean paying the lowest price for the same amount of energy, I’m all for that.

      You know that the lifetime cost of a solar farm is lower than the lifetime cost of an equivalent coal burning plant, in terms of price per unit, right?

      So as a business decision, there’s no probability coal burning would appease the Green of the US$.

    • Edim | April 19, 2014 at 2:34 pm |

      Bzzzt.

      The right place to look is Table 6, column 1.

      If you’re going to be carrying on business, you’re going to produce things at their minimum cost, not their average or maximum.

      And compare the prices in Table 1 to Table 6. If you’re going to do business building a plant that will operate for sixty years starting in 2020, then you’ll want the option that costs the least over the whole lifetime of the plant. The prices for non-carbon are the ones dropping, as Table 4 shows.

      Sure, if you include already built facilities, you can make fossil seem semi-attractive, but you can’t keep running ancient furnaces forever. Most of them are near end-of-life, and will cost far more to replace than they cost to build.

      And then there’s the synergy of pumped hydro with solar and wind: using excess energy generated off peak by solar and wind to pump hydro backwards makes hydro, solar and wind all more cost effective together than any one of them alone, so consumers have to pay LESS. You do something like that for fossil fuels, too: because it costs so much to restart the furnaces, they actually pay much cheaper hydroelectric producers to stop producing power .. so consumers have to pay MORE.

    • Bart R, your excuse is laughable! Can you read?

      Why do you think Germany is building all these coal plants? And coal (as fuel) is much more expensive than in the US.

    • Edim | April 19, 2014 at 5:07 pm |

      Politicians get elected for 2-6 year terms. Electric plants last 40-80 years.

      Business owners care about the lifetime of their investments.

      Politicians can’t see past the next election.

      And let’s face it, the fossil lobby has far deeper pockets built on old money than new technology has from money it hasn’t earned yet by being better.

  29. Oh my, the climate obsessed are disappearing the pause by playing with numbers: They could have chosen admitting error and kept honor. instead some seem to choose both being wrong and dishonorable.
    How sad.

    • the pause that never wause

    • the pause that never was is still killing the cause

    • I am still waiting for a statistically significant pause, anyone have one to share?

    • I will help you dredge. The pause we are talking about is the one that the alarmists are trying desperately to explain away, because the pause is killing the cause. The significant statistics you are looking for are found in a variety of public opinion polls that indicate that most folks ain’t scared of CAGW. Why worry, when it ain’t getting any hotter? Is it clear now, dredge?

  30. pokerguy (aka al neipris)

    It’s impossible to remove all risk from the world. At a certain point it’s good to remember that in the long run we’re all dead.

    One can always come up with highly unlikely but catastrophic scenarios. It’s clear to me that basing profoundly impactful policy decisions on them is simply not wise. One could argue it’s not even honest.

    • pokerguy (aka al neipris)

      “Joshie, why the roaring comeback after such a long absence?”

      Likely back from troll rehab.

  31. Interesting:

    Alarmism occurs when possible, unverified worst case scenarios are touted as almost certain to occur. U.S. Secretary of State John Kerry frequently does this, as does Joe Romm (and Rachendra Pachauri). A recent example from Dana Nuccitelli, John Cook and Stephen Lewandowsky:

    I seem to recall that when asked about the tribalism and name-calling and overt politicization so often seen here or at places like WUWT, Judith says that her concern is with respect to what members of the “climate community” have to say.

    But when describing the “alarmism,” as distinguished from legitimate concern related to high outcome function results from ACO2 emissions, suddenly Judith is predominantly interested in what non-climate scientists have to say.

    Selective reasoning is…er….um….selective, Judith.

    • Joshie, why the roaring comeback after such a long absence? Has Judith been on good behavior for an extended period, or have you been too ill to attend to your duties?

    • The A-Team is back!

      The hoax is still on!

      Andrew

    • pokerguy (aka al neipris)

      “Joshie, why the roaring comeback after such a long absence?”

      Likely back from troll rehab. In any case, welcome back. Somehow missed the nitpicks and the wildly off the mark misreadings. Just one request, try to be nicer to Judith.

    • If only Joshua was the “A team”.

  32. Tail benefit, anyone?
    =======

  33. I was renegotiating my contract with the TEAM, Don. I felt that even though I have been getting paid handsomely, I should get bonuses for dealing with some of the more tribalistic “skeptics.” Eventually, they came through.

    A nice steak dinner and a bottle of good wine tonight, thanks to you, bro.

    • Joshua

      Steak? Steak? Are you aware of the damage that causes to the environment? Have you no shame?

      (welcome back)

      tonyb

    • tony –

      I don’t care about the environment. I’m only in this for the Benjamins.

    • joshie, joshie

      I am sure that the TEAM is indifferent to, if not totally unaware of, the anonymously obscure and annoying character that you portray, online . I hope you made good use of time off from your avocation of inconsequential nitpicking.

  34. Fat tail events are real

    Earthquakes of scale 8, 9, 10
    Volcanoes of index 6, 7

    Getting another Ghawar crude oil reservoir is fat-tail. The last ain’t gonna happen. Time for alternative energies.

    • “Getting another Ghawar crude oil reservoir is fat-tail. The last ain’t gonna happen.”

      Er, isn’t that complete mathematical nonsense? One can state that the chances of finding a oil reservoir the size of the untapped Ghawar is very low, but if the distribution of unknown oil deposits has a fat-tail, then the chances of fining a field larger than Ghawar must be possible, unlikely, but possible.

    • There are plenty of fossil fuel, they question is, do we have the skills and resources to extract them.

      We have record unemployment in the US, but we don’t have the talent to create the capital we need to make use of that energy. We’ve also created a bunch of regulation that ridiculously increases the cost had we the talent.

    • Ghawar was the fat tail. The fish bowl has been thoroughly searched. See my model Dispersive Discovery and check where we are on the profile.

    • There are three methods for answering the ‘undiscovered Ghawar’ question quantitatively, without guesstimated fat tails. 1. Hubbert linearizations (e.g. by Deffeyes from Princeton. 2. Hyperbolic creaming curves e.g by Shell. 3. Probit transforms, e.g. by Patzek from Stanford. None produce fat tails in any traditional probabilistic sense. All give the same general answer.
      Read up before opining.
      WHT, it pains me that you could be right about future fossil fuels for the wrong reasons. That is not a win for science, nor a result to be lightly accepted.

  35. The less you know, the more import it is to sound the alarm.

    There are a million things we know nothing at all about in addition to climate change.

    I sound the alarms for these too.

    You could offset it all with an alarm tax.

  36. Steven Mosher

    “I take this brief discussion to indicate that the decision deliberation starts to become messy and complicated. It is not clear to me whether there are general principles which can guide rational decisions in such situations at all. This, however, must not serve as an excuse for simplifying the epistemic situation we face! If a policy decision requires a complex normative judgement, then democratically legitimised policy makers have arguably a hard job; it is, nevertheless, their job to balance and weigh the diverse risks of the alternative options.”

    The two most distracting approaches to simplifying the epistemic situation.

    1. Just use the scientific method
    2. the consensus says….

    funnily, one tends to propose a method that cannot be used in this type of problem, and the other, in the extreme, argues that the science is settled.

    we used to think philosophy was dead.

    hehe.

    • “To those who say there are no easy answers, I say you’re not looking hard enough”

      Bart Simpson

  37. From a thermodynamic perspective, it might be mentioned that a principle of least dissipation for nonequilibrium systems has long been sought and I happen to believe can be proved for steady-state systems beyond the linear dissipation regime near equilibrium. It implies minimal potential gradients and consequently minimal surface temperatures, i.e. Gaia must use all available parameters to keep Earth cool.

    Q

  38. Betz: “It is not clear to me whether there are general principles which can guide rational decisions in such situations at all.” My general principle: accept that the future will surprise us, and adopt capacity-increasing policies which are robust to a wide range of outcomes, including those unforeseen.

  39. Betz: “A surprise of the rst type occurs …” I wondered if an rst type was a technical term, then realised it should be “first”.

  40. JC: “My biggest concern is that by unduly (and almost exclusively) focusing on AGW that we are making a type 1 error: a possibility that has not been articulated might come true. These possibilities (e.g. abrupt climate change) are associated with natural climate variability, and possibly its interaction with AGW.

    “Pretending that all this can be characterized by a fat tail derived from estimates of climate sensitivity is highly misleading, in my opinion.

    “So I agree with Emanuel that we should think about worst cases (e.g. black swans and dragon kings); I disagree with him regarding how this should be approached scientifically and mathematically. However, undue focus on unverified worst case scenarios as a strategy for building political will for a particular policy option constitutes undesirable alarmism.”

    Quite so. All politicians and policy advisers need to grasp this.

  41. Judith, a thoughful post on several levels.
    The issue about properly communicating scenarios, especially when trying to marshal the troops for some action or change, has been explored by business schools in leadership, strategy, and organizational behavior disciplines. I am struck by how little of this practical ‘how to’ knowledge (which is board room staple stuff) is used in the political debates around climate. Apparently the IPCC set a tone and a style, and all else has fallen by the wayside. Plus politicians and their reps seem ever more confident that they can say anything ‘on authority’ and get away with it. I hope not.

    • “Doctors say that Nordberg has a 50-50 chance of living, though there’s only a 10 percent chance of that.”
      Detective Frank Drebin

  42. Hi Judith
    You wrote:
    “In my opinion, the most significant point in the IPCC AR5 WG1 report is their acknowledgment that they cannot create a meaningful pdf of climate sensitivity with a central tendency, and hence they only provide ranges with confidence levels (and they avoid identifying a best estimate of 3C as they did in the AR4). The strategy used in the AR5 is appropriate in context of scenario uncertainty, where they identify some bounds for sensitivity, and present some assessment of likelihood.”
    Well, imo AR5 used a double standard. On the one hand they did not give a best estimate for ECS. On the other hand they give projections based on the RCP scenarios and model ensembles. These models have an average ECS of 3.2. For example Stocker in a talk at KNMI said based on RCP8.5 we have only 25 years to go before we cross the 2 degrees limit. So in practice they do use a best estimate for ECS, namely that of the models.

    Marcel

  43. Interesting stuff – thanks for this post.

    One of the most important messages for this non-scientist is that scietific progress is not linear – it is lumpy, uneven and sometimes involves paradign shifts. The application of standard probability methods to scientific prediction is therefore fraught with peril.

    I agree with Faustino (as usual – BTW how are you?) in that the best that policymakers can do is to spread their bets, but not too widely. Just as the best predictor of tomorrow’s weather is today’s weather, most of the eggs need to be in the Business as Usual basket. But it makes sense to put a few in the baskets of less likely outcomes. So, even though it is fine today, you keep an umbrella around in case it isn’t. But, you don’t spend your entire income on building levee banks around your house.

    And, to reiterate a tired but important point, the problem with many of the scenarios and “probabilities” about global warming run by the alarmists is that they focus only on the negatives. Poor old Richard Tol is in the poo because he did the honest thing, which is to also consider the positives.

  44. Matthew R Marler

    Good post and good response by Roger A Pielke Sr.

    What I have not read so far here is something I have posted from time to time (though it might have been implicit in something I missed.) If you are going to be concerned with a “worst case” scenario, you should concern yourself with at least 5 worst case scenarios. For example: if humans invested all their resources in developing non-fossil fuel energy sources to the exclusion of everything else and the climate produced floods, droughts, etc that no one had anticipated, that could be at least as catastrophic as the warnings of a couple degree rise in global mean temp over some long but not known time span.

  45. I agree with the idea of tail risk, but think the “risk” is on both sides of the histogram. There is a risk of sharply higher global temperatures, but there’s also a risk of sharply lower temperatures. There is a risk that global warming will cause a massive catastrophe, but there is also a risk that whatever change there is, whether it be warming or cooling, will have a massively positive effect.

  46. A fan of *MORE* discourse

    BREAKING NEWS
    Two-Faced Denialism
    Imprison the HIV-Infected: YES
    Curtail CO2 Emissions: NO

    AIDS: A British View
    by Christopher Monckton

    There is only one way to stop AIDS. That is to screen the entire population regularly and to quarantine all carriers of the disease for life.

    Every member of the population should be blood-tested every month … all those found to be infected with the virus, even if only as carriers, should be isolated compulsorily, immediately, and permanently.

    Common-Sense Questions  How is it that Chris Monckton embraces the “long tail” of AIDS risk (so ardently as to advocate global-scale internment camps) … and yet that same Chris Monckton rejects the “long tail” of climate-change risk (so ardently as to smear young climate activists as H*tl*r Youth). And how is it that Chris Monckton remains (seemingly) unconscious of this blatant contradiction?

    More Common-Sense Questions  By what strange series of coincidences and/or back-door influence-peddling does Big Carbon’s staunch political ally and protector, the Republican National Committee, recurrently seek out, as its primary “expert witness” on climate-change … this same Chris Monckton?

    The Pathognomic Utility of “Unconscious Long-Tail Schizophrenia”  Denialist cognition and special-interest politics are mutually evident in present-day exhibitions of “unconscious long-tail schizophrenia,” to a degree that make the climate-change analyses of Pope Francis and James Hansen seem as sane-and-centrist as the administrations of Dwight Eisenhower and Bill Clinton!

    Conclusion  “Unconscious long-tail schizophrenia” can provide a useful pathognomonic indication of nonrational denialist cognition and/or political influence-peddling.

    \scriptstyle\rule[2.25ex]{0.01pt}{0.01pt}\,\boldsymbol{\overset{\scriptstyle\circ\wedge\circ}{\smile}\,\heartsuit\,{\displaystyle\text{\bfseries!!!}}\,\heartsuit\,\overset{\scriptstyle\circ\wedge\circ}{\smile}}\ \rule[-0.25ex]{0.01pt}{0.01pt}

    • Here is the full article

      https://docs.google.com/viewer?url=http://64.62.200.70/PERIODICAL/PDF/AmSpectator-1987jan/29-33/

      he was wrong, but it is worth reading in context of the time.

    • A fan of *MORE* discourse

      DocMartyn agrees He [Monckton] was wrong

      • In 1987 (twenty-seven years ago) consensus medical science was right, and Chris Monckton was utterly wrong, regarding global internment camps for HIV/AIDS patients.

      • In 2041 (twenty-seven years from now) consensus climate-change science will be appreciated as right, and Chris Monckton as utterly wrong, regarding the necessity for low-carbon energy economies.

      `Cuz that’s what the science is saying, plainly and simply, eh DocMartyn?

      Question  Why do denialists (and the RNC) like Chris Monckton so much?

      The rational world ponders!

      \scriptstyle\rule[2.25ex]{0.01pt}{0.01pt}\,\boldsymbol{\overset{\scriptstyle\circ\wedge\circ}{\smile}\,\heartsuit\,{\displaystyle\text{\bfseries!!!}}\,\heartsuit\,\overset{\scriptstyle\circ\wedge\circ}{\smile}}\ \rule[-0.25ex]{0.01pt}{0.01pt}

    • Public health isn’t science and consensus typically means you do the wrong things for far longer than you should.
      You seem a little shocked that someone would suggest internment for suffering from a disease; guess what happens to people with various chemical addictions?

    • A fan of *MORE* discourse

      DocMartyn defends Chris Monckton’s internment camps  “You seem a little shocked that someone would suggest internment for suffering from a disease; guess what happens to people with various chemical addictions?

      Denialist fantasies by DonMartyn, literature-links by FOMD.

      DocMartyn, your [implicit] suggestion that 8%-12% of all physicians be interned “compulsorily, immediately, permanently, universally and undeniably” (in Chris Monkton’s phrases) is novel to be sure!

      Have similar large-scale internment camps for social undesirables been tried before?

      The world wonders and ponders!

      Hmmmm … following your and Chris Monkton’s way of thinking, perhaps climate-change activists (and their families too) might be compelled to wear a green star, at all times and in all places? — or perhaps be branded with tattoos? — so that right-thinking citizens might shun them?

      Far-right denialist cognition undoubted is attracted to these ideas, eh Climate Etc readers?

      \scriptstyle\rule[2.25ex]{0.01pt}{0.01pt}\,\boldsymbol{\overset{\scriptstyle\circ\wedge\circ}{\smile}\,\heartsuit\,{\displaystyle\text{\bfseries!!!}}\,\heartsuit\,\overset{\scriptstyle\circ\wedge\circ}{\smile}}\ \rule[-0.25ex]{0.01pt}{0.01pt}

    • The U.S. has 760 prisoners per 100,000 citizens and just less than half are in prison due to drug offenses.

    • Doc,

      Like theft.

  47. Antonio (AKA "Un físico")

    I don’t agree with Dr. Emanuel. I am contacting him, as I did with JC. Let’s see if he agrees in giving me some feedback. (In that case, I will publish here below).

  48. “In my opinion, we have a strong profession obligation NOT to simply the uncertainty by portraying it as a pdf, when the situation is characterized by substantial uncertainty that is not statistical in nature.”

    NOT to simplify?

    I think to simplify it, is these guys have never accurately predicted anything.
    And strangers don’t need to explain to a little girl how she should cross the street, they should ask her where her mommy is.

  49. This is a plot of Mortality vs. Age, for the US(L) and UK(R)

    http://www.ssa.gov/policy/docs/workingpapers/wp111_chart1b.gif

    mortality is on a log axis.

    You could do the same plots for log(p)T vs [CO2] for the different estimates.

  50. Robert I Ellison

    ‘The richness of the El Nino behaviour, decade by decade and century by century, testifies to the fundamentally chaotic nature of the system that we are attempting to predict. It challenges the way in which we evaluate models and emphasizes the importance of continuing to focus on observing and understanding processes and phenomena in the climate system. It is also a classic demonstration of the need for ensemble prediction systems on all time scales in order to sample the range of possible outcomes that even the real world could produce. Nothing is certain.’ http://rsta.royalsocietypublishing.org/content/369/1956/4751.full

    Not having a good handle on prediction is the clever consensus. This implies that not much can be ruled out – including dramatic climate change in as little as 10 years. Realistically it suggests also that a CO2 control variable is one of a number of factors capable of driving climate past chaotic tipping points.

    The pragmatic response is broad and indirect. Economic development, education, health services, safe water and sanitation, infrastructure security, agricultural productivity, ecological conservation and restoration and energy research. These are responses with multiple benefits and nil downside.

  51. blueice2hotsea

    Judith Curry-

    I am no fan of alarmism. However, there are two fat tail events we must avoid: snowball earth and run-away greenhouse. Sea level glaciation at the equator is pretty much the end of terrestrial life. And even air-borne bacteria would have a tough time in a run-away scenario which could lead to total extinction event.

    So, I support President Obama’s geo-engineering initiative. The approach he has proposed (particulates in commercial aircraft exhaust) is IMO economical and sensible. My hope is it would be not used unless necessary and that it would be SO2 used to reduce albedo and not a proprietary chemical which enriched bribe-paying cronies.

    I would also add that while humans are adding well-mixed CO2 plant food to the atmosphere, we are now removing the SO2 because it would otherwise rain out as a locally poisonous pollutant. Yet, SO2 is part of a whole plant food which could contribute to plant health as an anti-fungal if well-mixed.

    • I think run-away GHE would be evident by now if it was plausible.

    • blueice2hotsea

      aaron, I agree. My point is that it is possible, and given the extreme downside, a minor expenditure is both painless and essential.

      When I lived in a small town with no crime I never locked my doors at night. In the big city where the odds are non-zero I do lock the outside doors. It’s quite painless. Do you lock your doors at night? Or do you say I’m paranoid?

    • blueice2hotsea,
      Runaway GHE is something we cannot trigger if we tried.
      Why the worry about it?
      And for geo-engineering, I think that until the side effects are more well described, we had best apply the idea of “first do no harm”.

    • “And for geo-engineering, I think that until the side effects are more well described, we had best apply the idea of “first do no harm”.”

      Hmm that’s interesting. Reminds me of

      As for CO2 emissions, I think that until the side effects are more well described, we had best apply the idea of “first do no harm”

      Of course no doubt that’s just pure crackpot alarmism whereas your statement is entirely sensible and reasoned /sarc

    • blueice2hotsea

      hunter – Runaway GHE is something we cannot trigger if we tried.

      Yes. I agree. Sorry about my alarmism. Even James Hansen now says that a Venus-like dead planet can not be caused by humans. Until now, my position has been that it likely would not happen due to increased cloud albedo, but my analysis was not rigorous.

      Still, there remains the possibility of a hyperthermal such as the Paleocene–Eocene Thermal Maximum. That has the extinction potential to wipe out humanity. The fuel source could be destabilized methane clathrate deposits, not necessarily triggered by human caused warming (e.g.. mutant microbes).

      What I am most interested in is open, small-scale research to aid in preparation for a potential micro-runaway (warmer or cooler) at the end of the pause. Climate and weather have both national strategic and military tactical importance. It’s difficult to imagine that off-budget, secret geo-engineering experimentation is not already commonplace. Let’s shine a light on it

  52. I agree with JC’s POV:

    “Alarmism occurs when possible, unverified worst case scenarios are touted as almost certain to occur. U.S. Secretary of State John Kerry frequently does this, as does Joe Romm (and Rachendra Pachauri). A recent example from Dana Nuccitelli, John Cook and Stephen Lewandowsky”

  53. If we assume that the planet Earth currently has average temperature of 15 C, Earth is not going to increase this average to more than 17 by 2100.

    I say assuming it’s 15 C, because there is no actual way to establish what Earth average temperature is. Or depending on how choose to measure Earth average temperature, one will get different results.

    So if one assume the planet Earth is currently 15 C, Earth isn’t going increase to 17 C average within time period up to 2100. But if it did, it would matter where on Earth it is getting this significant amount of warming.

    The reason Earth can be said to me around 15 C, is because Earth has a large and warm tropical ocean. Or the temperature of Greenland has little
    effect upon Earth’s average temperature. As size matters and Greenland is about 2.1 million out global surface of about 511 million square km.
    Likewise the Sahara region which is about 9 million square mile matters little
    in regard to Earth average temperature, but because it’s bigger it matter more than Greenland.
    The idea that Sahara desert could become hotter because of “global warming is absurd, but it could get warmer, as in say it’s nights could have a higher average temperature. [No region in last couple centuries has become hotter in terms noon day temperatures increasing]. The idea of world getting warmer is all about average temperatures, rather highest day temperatures.
    So say the Sahara region does get warmer in the period from now to the year 2100. Let’s pick a number, say 5 C warmer. So Sahara becomes 5 C warmer this has larger effect upon Earth15 C average temperature number as compared to Greenland becoming 5 C warmer.

    So I were to find myself transported to the year 2100, and I am informed that Sahara has increase by 5 C in average temperatures. My assumption would be that somehow this region transformed from natural desert into a place where a lot of crops are grown. Or that the Sahara somehow has had a lot of “natural” greening- the elevated CO2 levels could have been a factor. Or unless the sun has changed, would not associate are warmer Sahara with a hotter Sahara. I would wonder if the Arabs have managed to get more civilized. Perhaps there has been a significant reformation of Islam. If would be interesting.
    Now what if Greenland had warmed by 5 C. If Greenland had warmed by 5 C, I would interested to know what happen to all the glaciers on Earth- was crazy train engineer actual right, had the been significant reduction Himalaya glaciers by 2035? And if all the other glaciers on Earth had not melted significantly. Then next question would be, has the average elevation of Greenland somehow been reduced? Perhaps there is some fad which involves having Greenland glacier ice used in soda drinks.
    But if Greenland were 5 C warmer I would not expect all of glacial ice disappearing. I would guess people would be worried about the ice cap disappearing. Other then humans doing teraforming or some large volcanic event, I would be quite surprised if Greenland was 5 C warming.
    So Sahara warming by 5 C is somewhat plausible, and Greenland warming
    by 5 C is unlikely. Even if Greenland warmed by 5 C, it does not mean that much of Greenland glacier have melted, yet. But it would seem alarming in term what could happen in the future [+2100].
    Now if Greenland had warmed by 5 C, and it was not due to change of elevation. One could also guess that Canada and Russia had a similar increase in temperatures, and it seem the polar sea would completely melt each summer [most of the time].
    Which would seem like very welcome change for Canada and Russia. Such regions are large portion of land area on Earth, and it also like we gone to different planet. large amounts newly available arable land.
    It would not fix the definition of disaster, rather it hopeful and exciting.
    But doubt such changes would include worries about the future, in particular in regards to potential sea levels rise. And one imagine these countries becoming vastly more wealthy, and perhaps wanting even warmer world and having enough power to enable this desire.

    But as said I don’t think global temperature will rise as much as 3 C before year 2100, whereas by year 2200 or 2300 it could possible, and eventually Canada and Russia might be a better place to live,

    • blueice2hotsea

      gbaikie-

      I follow much of your reasoning, but I wonder why a warmer cloudier world wouldn’t have Greenland avg temp increasing while Sahara avg would be decreasing. Please comment. thanks

    • blueice2hotsea

      This is where I got lost:
      So Sahara warming by 5 C is somewhat plausible, and Greenland warming by 5 C is unlikely

    • –This is where I got lost:
      So Sahara warming by 5 C is somewhat plausible, and Greenland warming by 5 C is unlikely–

      Ok, let me say it this way. Rapid warming of Sahara is possible.
      In number of ways,and includes humans creating warmer condition due irrigation or development of the land. So don’t think there is much chance of 5 C of warming within say time period of 2030, but would not rule it out sometime beyond 2050.
      Or if there was the human desire/resources/effort available, we could warm Sahara within 10 years. Plus other variable slight “natural” effect of greening occurring now. So even without any near term human planned development the greening could continue and perhaps longer it continues
      more chance of human related project or improvement.

      With Greenland, there is lack of heat available warm it or melt the ice.

      So If our average ocean temperature was warmer, it would be possible for Greenland to become warmer. In same way that Europe is currently warmer due to having Gulf Stream transfer tropic heat to these high latitudes.
      I see no reason to assume the gulf stream will bring significantly more warmth up to Greenland, and the average ocean temperature can not warm much within a century of time.
      So that leaves some sort of atmospheric caused warming of Greenland, whereas it’s possible to have variability and so warmer years and decades
      which may swing from cooler periods to warmer periods [yearly/decadal] and for 5 C difference in average temperature, such variations will not cause much glacial ice to melt. For instance as what occurred in 2012:
      http://london.usembassy.gov/eande328.html
      But fundamental problem of such atmospheric warming of with Greenland is related to the sun not getting very high above horizon.
      And with sun low on horizon, if you point a solar panel at the sun, you do not get much solar energy.
      As example Germany is lousy place to harvest solar energy because one only gets some solar energy near the summer when sun is higher above horizon. Plus Germany is cloudy dung summer.
      And Greenland would be even a worse place to harvest solar energy as compared to Germany.
      And other factor is if you want to harvest solar at high latitude, one solar panel at high angle. So if put solar on level ground, then really hardly any solar energy. And though one can have hills and such,on average the land is level and on average gets very little solar heat reaching the surface, even if skies are clear of clouds and one constant sunlight during summer.
      Though the net result of low level clouds mentioned above article probably warm the surface more than compared to if there was clear skies. But this is weather.

  54. Outside of climate science, people (and sometimes their governments) purchase insurance against risks. Most homeowners insure their homes against fire and other catastrophes, but many do so simply because they can’t get a mortgage without such insurance. Some people buy life insurance to protect their families against the death of a breadwinner, but less affluent families generally feel that can’t afford to ensure themselves against this risk. Relatively few people by disability insurance (which is far more expensive than life insurance) to cover the risk that a breadwinner won’t be able to continue his current job due to some disability.

    The less-developed nations of the world can’t afford to pay much, if anything, to reduce the risk of catastrophic climate change (say ECS>3). If they can’t afford it, the mitigation efforts of developed countries probably won’t make much difference. China’s CO2 emissions are now double the US and are likely to be triple in other decade. India and another 5 billion want to join them.

    You can discuss tail-risk until you are blue in the face – but undeveloped countries basically can’t afford to listen. Maybe they will pay attention to central estimates.

    • I kind of think the idea of climate fat tail risk is bogus. We’re basically talking about barely plausible events and multiplying the cost beyond reason. We also aren’t considering our biases. We over focus on costs, and it’s generally a good thing. But, when there is so much uncertainty, and we’re talking about a very gradual change, these biases work against us. We ignore the benefits and also the likely reduction of risk. Not only that, but the likelihood of using data we gather to not only mitigate costs of changes, but benefit from them.

      These distributions are just the product of imagination. PDF tails are likely fantastically thin, and centered around 1.1C. When we multiply them by cost, the left tail is probably fatter than the right and a shift in pdf reduces risk.

    • “PDF tails are likely fantastically thin, and centered around 1.1C. When we multiply them by cost, the left tail is probably fatter than the right and a shift in pdf reduces risk.”

      Clarification. The existing costs and pdf are probably fatter on the left. The global average temperature sensitivity is probably thin, but slightly longer and fatter on the right. The shift would reduce the fatter cooling cost tail and make the thinner warming cost slightly fatter.

  55. As a Catholic who has followed Pope Francis’ writings extensively, he is not on the record as embracing the catastrophic global warming scenario. In fact, if you actually read the piece linked, the scientists working with the Vatican express concern about food supply and energy and their effects on the poor.

    • Mike,
      Good point. Most media does an incredibly poor job reporting what the Catholic church says or does. Anyone making snap judgements about what a Jesuit is saying on a pop-culture issue is almost always making an error.

  56. It would be a good start if talking about low probability events, to actually state they are low probability. It is routine today to talk about drastic sea level rise, large extinctions, and such and never bother stating it is a low probability event. Much of this is stated as low probability by “the science”, but this somehow gets lost in translation on its way to the media, and we are told incorrectly what “the science” says. repeatedly.

    It happens often enough that one can conclude many of the overt partisans are doing it intentionally. It would seem that this is backfiring as nobody takes these warnings seriously.

  57. ”Climatologist” can become the best script writers for Walt Disney… very fertile imagination…

    their followers should start discussing: ”what happens when is proven that is no such a thing as GLOBAL warming?! Who is going to compensate and reimburse the suffering taxpayer, the squandered billions?!”

  58. The IPCC does not talk about tail risks in WG2 or WG3. They consider 4 C rises, and CO2 mitigation that can prevent it. A lot of the disconnect here is that one side of the debate considers 4 C as way down in the fat tail, and therefore not even worth considering effects of, let alone trying to avoid, while the other sees this as highly likely for unmitigated CO2 levels exceeding 700 ppm a century from now. Debate specific probabilities, like that of 4 C, not fat tails, which are too abstract.

    • David Wojick

      4C is a green dream so there is nothing to debate. The fallacies are well established.

    • JC considers 4 C as an unverified worst case scenario, which is not what it was supposed to be. It is supposed to be the most likely warming scenario for the most likely unmitigated scenario. In terms of planning, it makes most sense to plan for the center of the uncertainty range. This is not meant to be the precautionary principle, just common sense, middle-of-the-road planning. The framing as the precautionary principle misses the point because it then puts the focus on tail events, which is not what 4 C is about.

    • 4C at 700 ppm of CO2 probably way too low. We absolutely do not want to see 700 ppm CO2.

  59. Mainly what the hiatus has brought about is AGW alarmists now reject the ‘hockey stick.’ That’s how long it takes to expose a hoax.

  60. David Wojick

    The lower bound of sensitivity is not “well defined” if by sensitivity we mean what will actually be the case if and when CO2 levels double from 280ppm. We could be falling into an ice age by then, for all we know now. And if sensitivity does not mean what will actually happen then it is a misleading academic exercise at best, more likely a scare tactic, in short a hoax.

  61. “Alarmism occurs when possible, unverified worst case scenarios are touted as almost certain to occur.” JC

    My, what a convenient straw-man.

    The need for this kind of hyperbole suggests a weak argument.

    • Yet the climate obsessed alarmists live on that straw.

    • nottawa rafter

      Not only do they live on it, they thrive. Without it they shrivel up.

    • John Carpenter

      Tell it to John Kerry, Michael. Or how about Bill McKibbon. You seem so confident this strategy is not used.

    • John,

      I don’t know what John Kerry has said. Judith provided only one link, which absolutely does not say what Judith clamis.

    • John –

      Whether or not it is used, don’t you think that Judith’s selectivity in concern about who says what to be noteworthy?

      http://judithcurry.com/2014/04/18/worst-case-scenario-versus-fat-tail/#comment-526224

    • Actually, I thought it was as good of a description of alarmism as any I’ve heard. If you know a better one, Michael, do share it.

    • John Carpenter

      Michael, I think the this speech by John Kerry certainly qualifies as an example of the use of possible, unverified worst case scenarios touted as almost certain and happening now.

      http://www.state.gov/secretary/remarks/2014/02/221704.htm

    • John Carpenter

      Joshua, glad to see you back after taking a break…

      I think it is hard to hold anyone to a single thing they say forever. I don’t know the exact context for the example you give, however, it is not really noteworthy for anyone who has followed JC and her writings over the last several years that she is more concerned about how her peers represent their field and the credibility of it to the general public. I have to agree that alarmism tends make people turn the other way. It is not a winning strategy and it hasn’t really been effective on either side of the debate. Low probability scenarios and events should be represented as what they are… low probability. Not that it isn’t possible, but that it is very unlikely to happen. Hyping the worst case as a strategy to get things to happen usually backfires as most people think there may be an ulterior motive behind the hype. Suspicion is not an element you want creeping in when making important decisions.

  62. People in most fields outside of it [economics] do not have problems eliminating extreme values from their sample, when the difference in payoff between outcomes is not significant, which is generally the case in education and medicine…

    A casual weather forecaster does the same with extreme temperatures — an unusual occurrence might be deemed to skew the overall result (though we will see that this may turn out to be a mistake when it comes to forecasting future properties of the ice cap). So people in finance borrow the technique and, ignore infrequent events, not noticing that the effect of a rare event can bankrupt a company.

    Many scientists in the physical world are also subject to such foolishness, misreading statistics. One flagrant example is in the global-warming debate. Many scientists failed to notice it in its early stages as they removed from their sample the spikes in temperature, under the belief that these were not likely to recur. It may be a good idea to take out the extremes when computing the average temperatures for vacation scheduling. But it does not work when we study the physical properties of the weather — particularly when one cares about a cumulative effect. These scientists initially ignored the fact that these spikes, although rare, had the effect of adding disproportionately to the cumulative melting of the ice cap. Just as in finance, an event, although rare, that brings large consequences cannot just be ignored.

    ~Nassim Nicholas Taleb, Fooled by Randomness (2004)

    • Note my comment below: the nasties routinely attributed to warming are actually historically and theoretically the consequences of cooling, resulting, amongst other things, in recommendations 180° out of synch with what would be worst-case from AGW, were it real. Precautionary adaptations on those assumptions, however, are likely to come in handy, paradoxically, when the Big Chill hits! Because they got it ALL wrong. Hilarious!

  63. What we least expect may pose the greatest danger, e.g., a car swerving and running over the girl on the sidewalk in Kerry Emanuel’s Climate Change National Forum.

    In Nov 2009, Climategate emails revealed an unexpected danger:

    http://judithcurry.com/2010/11/19/what-have-we-learned-from-climategate-2/#comment-526573

  64. If we believe the paleoclimate cycles in the IPCC AR5 report, then we are near the peak and headed for a 10,000 declining temperature cycle.

    So what about the tail risk of colder?

    • They are the same as the mis-attributed risks of AGW, at least until the Ice Sheets start to march again.

  65. John Vonderlin

    Earlier this week I read Kerry Emanuel’s essay and was so irritated I commented, something I rarely bother to do on the many forums I monitor. I just checked and saw it was moderated, which wasn’t entirely a surprise given my angry reaction to his arrogance. I had written: “Wow. One hundred thousand simulations made by an integrated assessment model, why that’s just like reality, isn’t it? Without arguing how poorly models have done so far in predicting the complex, chaotic dynamics of Earth’s climate, I’d rather focus on the moral bankruptcy of your metaphor and especially of accompanying it with pictures of a young girl facing traffic. I’m reminded of a parody magazine cover I once saw with a puppy with a gun to its head with the headline, “Buy this Magazine or We’ll Shoot This Dog.” To sink to your level of argumentation, I’d simply point out that on our local news channel tonight there was a story about a young child being run over while crossing the street, both with the light and in the crosswalk. Perhaps, some know-it-all with his GIGO computer simulations had assured them they would be just fine if they didn’t cross in the middle of the block. Perhaps, with the false security generated by an authority figure’s assertions that they’d be fine if they just did as they were told, they let their guard down. I wonder how that would fit in your fat tail? Uncertainty is a scientific truism that should be proselytized from every street corner. It is something the common man can understand just fine, without child-killing metaphors, whatever you smarmy elitists believe.”
    I wish I had left out a few lines, but by using a metaphor that seems to imply if you don’t agree with him (the rational adult) you’re a potential child killer, he just rubbed me the wrong way. Skimming the comments I don’t see anybody else raising this issue, so maybe I’m missing something. Can anyone give me another example of a picture of a young child facing a dangerous situation being used to bolster a scientific argument?

    • A fan of *MORE* discourse

      John Vonderlin asks “Can anyone give me another example of a picture of a young child facing a dangerous situation being used to bolster a scientific argument?

      Question asked by John Vonderlin, answered by FOMD.

      • Denial of human equality was bad for past generations,

      • Denial of medical risk is bad for present generations,

      • Denial of climate risk is bad for future generations.

      The history of denialist cognition is mighty sobering, ain’t it?

      What is your next question, John Vonderlin?

      \scriptstyle\rule[2.25ex]{0.01pt}{0.01pt}\,\boldsymbol{\overset{\scriptstyle\circ\wedge\circ}{\smile}\,\heartsuit\,{\displaystyle\text{\bfseries!!!}}\,\heartsuit\,\overset{\scriptstyle\circ\wedge\circ}{\smile}}\ \rule[-0.25ex]{0.01pt}{0.01pt}

  66. Alex Hamilton

    You are totally wrong in thinking that carbon dioxide is a primary cause of warming.

    Radiation in just a few spectral bands from carbon dioxide can never cause a warmer surface to increase in temperature. It can have a minuscule effect slowing down radiative cooling, but virtually all the slowing of surface cooling is by conduction at the surface-atmosphere boundary. The energy thus absorbed primarily by nitrogen and oxygen molecules subsequently finds its way by diffusion into water vapor, carbon dioxide and other radiating molecules, all of which act like holes in the nitrogen-oxygen blanket, radiating energy out of the atmosphere.

    There is no need for any warming by radiation anyway. It is now well-known and proven empirically that a thermal gradient forms at the molecular level in the tropospheres of any planet with a significant atmosphere. On Earth the surface temperature would be a few degrees hotter if there were no water vapor, but it is cooler because water vapor and other radiating molecules (carbon dioxide included) help to cool the lower troposphere by radiating energy to higher altitudes and to space.

    That is what physics tells us. From my reading of what climatologists have assumed, I find their writings to be a complete travesty of physics.

    • nottawa rafter

      Tell that to Mosher

    • John Carpenter

      “Radiation in just a few spectral bands from carbon dioxide can never cause a warmer surface to increase in temperature.”

      It may be just a few spectral bands, but when you add in the rotational coupling those bands end up occupying a large swath of energy that primarily coincides with the black body radiation the earth emits. Radiative heat transfer physics is settled science, arguing that you are right and all of climate science is wrong on this well known effect is not going to get you too far. The argument is to what degree of warming will we get and if it will be a problem or not.

    • You got one thing right there.

      Carbon dioxide in the atmosphere is warmed by conduction and convection, not just from radiation.

      And then the CO2 radiates in all directions.

  67. Tail risk is fine to talk about but only if considered symmetrically. There is the tail risk associated with huge climate sensitivities but there are also other forms of tail risk such as:

    1) The possibility that global warming is preventing or delaying an ice age (the outcome function here dwarves all extreme warming scenarios but an order of magnitude)

    2) The possibility that attempts to stop global warming will lead to economic disaster

    These tails risks are usually ignored.

    • –1) The possibility that global warming is preventing or delaying an ice age (the outcome function here dwarves all extreme warming scenarios but an order of magnitude)

      2) The possibility that attempts to stop global warming will lead to economic disaster–

      I don’t think rising CO2 levels will affect delaying ice age. But it would nice to know what caused cooling of Little Ice age.
      Nor do I think CO2 levels had anything with ending Little Ice age.

      As for 2) I don’t regard it as possibility, but rather attempts to stop global warming has lead to economic disaster.
      And generally speaking nothing the climate can do compares to the damages done by the political class.

    • Yes it is interesting how climate skeptics so adamantly believe reducing CO2 emissions harms the economy.

      More than a bit hypocritical given their stance on science.

      A doubling of CO2 is going to cause significant global warming based on physics, the science is quite clear on that. But they won’t accept that, they’ll try to throw up doubts and come up with bizarre mechanisms by which nature might negate it entirely (evaporation??)

      But on the other-hand they believe a tax or cap on CO2 emissions will definitely cause significant economic harm. But what’s that based on? Their gut feeling? Economic models (would be a bit rich for them to be relying on models)? Extrapolations?

      Another thing, they complain bitterly about alarmism when it comes to CO2 saying that disaster isn’t proven therefore there is nothing to worry about. But they are happy to be alarmist when it comes to the economy, warning that a global carbon tax would collapse civilization.

      You don’t see them ever arguing that the economy has negative feedbacks that would prevent that. You won’t see them even entertaining the idea that maybe CO2 taxes will be good for the economy. After-all the economy is as complex and chaotic as climate. It has myriad of feedbacks. But they won’t ever play that card and suggest those feedbacks in the economy might dampen the impact of capping CO2.

    • “A doubling of CO2 is going to cause significant global warming based on physics, the science is quite clear on that.”

      This is simply not true, but you won’t accept that, for some reason.

    • –But on the other-hand they believe a tax or cap on CO2 emissions will definitely cause significant economic harm. But what’s that based on? Their gut feeling? Economic models (would be a bit rich for them to be relying on models)? Extrapolations?–

      Price control on condoms, would do significant economic harm- but a tax or cap on CO2 simply does far more economic harm.
      You probably don’t see the harm in price control on condoms and you imagine that Obamacare is best thing the government has done in quite a awhile. Because you probably, are someone believes the only problems in this world can be resolve if governments could have more control of things.

    • thisisnotgoodtogo

      Lolwot says:
      “Yes it is interesting how climate skeptics so adamantly believe reducing CO2 emissions harms the econom”

      Where do they do that, Lolwot?

      You seem to have substituted the intended goal for actions.

      Why would you have done such a thing?

    • thisisnotgoodtogo

      CO2 does enhance plant growth and that doesn’t depend on crazy modeling to prove.

  68. The other more important point is that the moral of the story with tail risk is that you want your system to be robust, resilient and adaptable.

    Tail risks are inherently difficult to reason about because they seldomly occur and the tail risk you expect is often not the one that happens. And there are a number of events that can hit you in the tails. Non-tail risks are much easier to deal with because you are used to them and they are expected.

    Thus you don’t deal with tail risks by modelling them or doing economic calculations with them. This is stupid. You deal with tail risks by constructing systems that are able to adapt when they do occur.

  69. Do we really need a mocked up Science of Dunno? With its own fashionable terminologies and – god help us – statistics? If you are uncertain about something, please don’t be too certain about how uncertain. (And avoid altogether the ultimate sales ticket number of 97. It never fails to move merchandise but looks a bit cheap as scholarship.)

    We live on a planet which is hot and mushy and know very little about its heat and mush. Then there’s that mysterious hydrosphere which is rather large, won’t stay still or constant in any way – and even wants to interact disturbingly with the hot-‘n-mushy below.

    Taking into account also that the area beyond our atmosphere (called space) is many football fields in size and still holds a surprise or two…

    Maybe a simple dunno will serve, until you really do know something?

    Stay intellectually chaste. Dunno means dunno.

  70. thisisnotgoodtogo

    This made me think deep..
    I decided that it’s imperative to discuss with the children best case scenarios and how we should be kind to Bill Gates when he becomes our butler.

  71. thisisnotgoodtogo

    Emmanuel is a different guy when he talks to Isaac Held. Mostly he says stuff like:

    “A few comments on this: First, there is, to the best of my knowledge, no theory of tropical cyclones in which SST (relative or absolute) plays any role. With the minor exception of radiative transfer from the sea (which one expects plays little direct role in hurricane formation or intensification), the atmosphere only knows about turbulent heat and moisture fluxes from the sea, which depend on wind speed and air-sea disequilibrium”.

  72. A teacher of medicine and Harley Street consulting physician once said to me,

    “When we first look at symptoms we think “pigeons” not “golden eagles”. Only when we can rule out common ailments do we start working through the catalogue of rate illnesses.

    I will start thinking that global warming is not naturally induced if it last for more than 30 years without a significant pause. Because it seems certain to me that the World Meteorological Organization (WMO) ought to redefine climate as the average weather for 60 years, not 30 years based on what we know now about oceanic oscillations.

  73. There is a lot of gnashing of mental gears here, when there is a fairly simple response that, I believe, is determinative. In light of the increasing rate of technological change, and the limitations of human beings, there is no way to predict 100 years into the future. Anything we would do now to attempt to solve a perceived problem 100 years into the future is doomed to failure. We should attempt to plan 20 to 25 years out, and we are forced to let the chips fall where they may past that point in time.

    It is hard for me to think of any successful efforts to plan 100 years to the future since 1850 (when industrial age took hold), and I can think of abject failures. 1. The Vietnam war, which was based on the futurist domino theory and 2. China’s Great Leap Forward

    JD

    • “Anything we would do now to attempt to solve a perceived problem 100 years into the future is doomed to failure”

      Not so. The issue is an accumulating CO2 level in the atmosphere. The simple act of curbing CO2 emissions now will directly slow or even halt that increase such that in 100 years time any impacts from elevated CO2 will be avoided or lessened.

      An successful similar example I can think of is the montreal protocol

    • A fan of *MORE* discourse

      JD Ohio claims [wrongly]  “There is  no  a good way to predict 100 years into the future.”

      Foolishness by JD Ohio, facts & foresight by FOMD.

      A century in the past is when our family’s farm-fields had already been plowed for fifty years. A century in the future is where our family’s great-grandchildren will live. These are common-sense reasons why neither the centuries past, nor the centuries to some are distant from us, eh JD Ohio?

      The bounded cognition and self-centered moral values of faux-conservative denialism conceives neither these ordinary family realities, nor these centennial time-scales, eh Climate Etc readers?

      \scriptstyle\rule[2.25ex]{0.01pt}{0.01pt}\,\boldsymbol{\overset{\scriptstyle\circ\wedge\circ}{\smile}\,\heartsuit\,{\displaystyle\text{\bfseries!!!}}\,\heartsuit\,\overset{\scriptstyle\circ\wedge\circ}{\smile}}\ \rule[-0.25ex]{0.01pt}{0.01pt}

  74. “The bounded cognition and self-centered moral values of faux-conservative denialism conceives neither these ordinary family realities, nor these centennial time-scales, eh Climate Etc readers?” Thanks for the wonderful joke of the mush of what are to you sophisticated thoughts, but are in reality meaningless, but very humorous, drivel.

    The Montreal Protocol worked over about 20 years. Also, it was not as nearly economically extensive and far reaching as the effort to totally re-engineer the world’s energy supplies. Try again.

    Also, looking forward to more of your very funny faux sophisticated “thoughts” although I won’t waste my time replying to them.

    • A fan of *MORE* discourse

      JD Ohio says “Looking forward to more of your … sophisticated thoughts!”

      It is my pleasure to oblige your request, JD Ohio!

      Year-by-year  Tail-risks almost never eventuate.
      Decade-by-decade  Tail-risks are sporadic.
      Century-by-century  Tail-risks are inevitable.
      Millennium-by-Millennium  Tail-risks happend over-and-over.

      Isn’t that why politicians, business CEOs, sociopaths, denialists, and children all disregard tail-risks? Because all of them discount the future?

      Isn’t that why farmers, and (grand)parents, and spiritual leaders all consider tail-risks carefully? Because all of them value the future?

      The world wonders … and ponders, eh Climate Etc readers?

      Conclusion  The climate-change debate is mainly about science-guided foresight, personal integrity, and moral values.

      Thank you for your inquiry, JD Ohio!

      \scriptstyle\rule[2.25ex]{0.01pt}{0.01pt}\,\boldsymbol{\overset{\scriptstyle\circ\wedge\circ}{\smile}\,\heartsuit\,{\displaystyle\text{\bfseries!!!}}\,\heartsuit\,\overset{\scriptstyle\circ\wedge\circ}{\smile}}\ \rule[-0.25ex]{0.01pt}{0.01pt}

  75. Judith, I posted a comment last evening which didn’t publish. Probably because I used a foul word. Can you publish it and just snip the word?

    Thanks,

    aaron

  76. Risk management must deal with tail events, because that is where the real risk lies.

  77. Robert I Ellison

    Here it is shown that hindcast experiments can successfully capture many features associated with the 1976/77 and 1998/99 climate shifts. For instance, hindcast experiments started from the beginning of 1976 can capture sea surface temperature (SST) warming in the central-eastern equatorial Pacific and the positive phase of the Pacific decadal oscillation (PDO) throughout the 9 years following the 1976/77 climate shift, including the deepening of the Aleutian low pressure system. Hindcast experiments started from the beginning of 1998 can also capture part of the anomalous conditions during the 4 years after the 1998/99 climate. The authors argue that the dynamical adjustment of heat content anomalies that are present in the initial conditions in the tropics is important for the successful hindcast of the two climate shifts. http://journals.ametsoc.org/doi/abs/10.1175/JCLI-D-12-00626.1

    Hindcast is one thing – the smart money is on several unpredictable – and possibly extreme – climate shifts this century. The smart response is to ask what pragmatically – that is while maximising global economic development – can be done about minimizing anthropogenic changes to the global energy budget.

    • “the smart money is on several unpredictable – and possibly extreme – climate shifts this century. The smart response is to ask what pragmatically – that is while maximising global economic development – can be done about minimizing anthropogenic changes to the global energy budget.”
      —–
      Unfortunately, the natural interconnected biosphere-hydrosphere-atmosphere-lithosphere systems of spaceship earth could give a rats ass about “maximizing global economic development”. It will be up to humans to alter their paradigm and modes of living on this planet such that Anthropocene Management and stewardship of spaceship earth are one in the same. There”ll need to be a new metric for human success other than “maximum global economic development”. Surely our brains are big enough to see the world as more than our toilet or future open pit coal mine.

    • Robert I Ellison

      Maximising economic opportunity is the sine qua non of human and societal development this century. It is critical to providing resources for the obvious societal and population constraint benefits of health, education, safe water and sanitation, resilient infrastructure, ecological conservation and restoration, energy research, increasing agricultural productivity.

      The way forward is pretty obvious – and in fact unstoppable – despite economic degrowth delusions from pissant progressives.

    • The dream of eternal economic growth, ever onward, ever upward, eh? Of course the only thing that wants to grow forever is cancer. There may be some parallelism here. There is a finite carrying capacity to the planet and the anthropocentric notion that humans are the most important species on the planet (a species set for some eternal economic growth!) is probably somewhat of a leftover from some religious heritage – “gods image”, center of creation, and the like.

    • You do realise that without economic growth the poor stay poor, even if the population doesn’t grow.

    • Robert I Ellison

      When I hear the word limits – I think not here and not now.

      http://www.one.org/international/issues/

      http://www.copenhagenconsensus.com/

      http://www.un.org/millenniumgoals/

      It is all not merely compatible but essential with actual progress on a multi-gas and multi-objective environmental policy. Everything else is just empty and morally corrupt rhetoric.

  78. Obligation “a strong professional obligation NOT to simply [simplify] the uncertainty” as a pdf …. Excellent point, and is amplified by the historically strongly contra-indicated statements about downside consequences of “warming”, which in fact are mostly the observed and theoretically predictable and “consistent” results of cooling! The supposed disastrous consequences are chimeras.

  79. Free speech laws have always had the protection of political speech at their core. Too many on the political left are engaged in activities designed to curtail or limit political speech these days. Although the public is seemingly not aroused by it, Climate Change is now one of the most hotly contested subjects in the entire realm of political speech. It is the activist political left trying to squelch dissident speech on that battleground. Mann is a member of that group. Steyn is a skeptical rightist with a long history of activism on behalf of freedom of expression. He’s fighting against Mann and his cohorts, and Mann will rue the day he decided to include Steyn in this particular lawsuit.

    But Mann’s suit against Steyn et al and his even more ridiculous suit against Tim Ball represent only a portion of his activities and those of others who align with him to restrict speech and impose prior restraint, censorship and blackballing of publications. This is all detailed in his emails released in the Climategate/FOI affair. Every time a sympathetic editor resigns to protest what he claims to be a bad paper, that is an attempt to suppress dissent. It parades as a concern for quality, but it is almost invariably much more than that. They want the paper and papers like it suppressed because they challenge the monopoly on scientific information and viewpoints the warmists are trying to establish. And it also serves as a warning to others who might want to challenge the “consensus.” “Don’t even think of writing a paper that challenges our findings,” seems to be the message.

    I”ve started calling these people the Climate Change Cheka because that is how they are behaving. They are trying to monopolize the dissemination of scientific knowledge in a way that is authoritarian and entirely unscientific. The free exchange of ideas, theories and potentially damaging data is anathema to them. It frightens them.

    It was Stalin who said, “Ideas are more powerful than guns. We would not let our enemies have guns, why should we let them have ideas?”

  80. JC says “In my opinion, we have a strong profession obligation NOT to simply the uncertainty by portraying it as a pdf”.
    Doesn’t this throw Nic Lewis under the bus? His whole effort is aimed at getting a PDF as a bottom line. That’s all he does. He’s even had some featured posts. How quickly fortunes change in the skeptical world. So fickle.

  81. That’s interesting, jimmy dee. Do you have a quote handy that indicates that Judith formerly endorsed the idea of getting a pdf as a bottom line? You must have read that somewhere. Or have you just made it up?

  82. I don’t see the part where Judith endorsed the idea of getting a pdf as the bottom. She said something about an overview and alternative assessments, but I didn’t see anything about a pdf bottom line. Please quote it, jimmy dee.

    • She says “Climate sensitivity and estimates of its uncertainty are key inputs into the economic models that drive cost-benefit analyses and estimates of the social cost of carbon.”
      If you read what I said, it was that Nic Lewis gets climate sensitivity as a bottom line. Above she seems to think this is valuable, and she wrote an endorsing Foreword. Is this not clear by now?

    • I read that already, jimmy. “she seems to think” What? That doesn’t do it, jimmy disingenuous. You are just making crap up. I am done with you.

  83. Pingback: Weekly Climate and Energy News Roundup | Watts Up With That?

  84. Climate sensitivity is definitely not characterized by #1, rather it is characterized by #2 or #4.

    I strongly disagree. It is very clearly characterized by #5: “ambiguous sign or trend.”

    The two leading theories of 20th century warming are a) that it was caused by the 80 year grand maximum of solar magnetic activity that began in the early 1920s or b) that it was caused by human increments to CO2. The EVIDENCE all points to a, which the “consensus” dismisses on the grounds that they don’t like the available theories of “solar amplification” (of how solar variation could be having a greater impact on global temperature than the very slight variation in total solar insolation would be expected to cause). That is, the “consensus” puts theory over evidence, the exact definition of anti-science, but set that aside.

    We have these two competing theories. Risk analysis as economists understand proceeds weighing the value of each possible outcome by the probability of its occurring if a particular choice is made. These weighted sums are the expected values from making the different available choices. If the choices themselves are costly these costs need to be subtracted from the expected values they produce to find the choice that yields the highest net expected value.

    When there are two different theories of how events will unfold, the job of the risk assessor is to assess the likelihoods that theory a, theory b, or some other competing account, is right. THIS is where all of the “consensus” risk analyses utterly violate standard economic analysis. They don’t give any weight to the competing theories at all, but simply assume that the outcomes of the different available choices are all what the CO2 warming theory says, accounting only the uncertainties that exist WITHIN the CO2-warming theory. The likelihood that the CO2-warming theory is WRONG is never accounted.

    To an economist (my background), this is misfeasance, or even malfeasance. If an economist performed a professional risk-assessment for hire without accounting the likelihood that a competing theory was right he could be sued in court for failing to perform the most basic due diligence. This is very basic stuff and yet EVERY economist who engages in these analyses assumes from the outset that the CO2-warming theory is correct.

    That’s the power of politicized science. The only research money that is available is for those who work within the “consensus” view. Even economist Richard Tol does this. He is the scourge of the “consensus” now only because he rejects the high damage assessments that the IPCC estimates for modest levels of warming, he rejects the attempts to model how the CO2-levels emitted by the world economy will respond different policy regimes and to assumed climate impacts, and he rejects the sluggishness with which the IPCC changes its alarmist projections in response to moderated estimates of key factors like the level of climate sensitivity. The latter is the closest that Tol comes to accounting the possibility that the CO2 warming theory is wrong, but he is actually only looking at the IPCCs own scientific assessments. He is not accounting the majority probability that the scientific “consensus” is radically wrong.

    If a proper economic risk analysis is conducted then the fact that there are competing theories of what is going on does not preclude the formation of a full probability density function. Here I would say that the typology of different types of analysis of uncertainty presented by Risbey and Kandlikar is just wrong. If two different theories give two different density functions, just add these density functions together point by point, each weighted at each point by the probabilities that each theory is right. “Ambiguous trends” does not at all mean you can’t have a single density function. The problem lies elsewhere: it is the failure to properly weigh the competing theories of what drives global temperature.

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  86. For those readers who, like me, are unfamiliar with the definitions of “black swans” and “dragon kings” — see A guide into the weird numbers that run our world, describing both financial bubbles & climate change, 22 April 2014.

    This has excerpts from Didier Sornette articles discuss the strange extremes that live in the tails of probability distributions — and that shape our world (both the physical and social worlds).

  87. http://www.sciencemag.org/content/257/5070/644.short

    Huh. Deglaciation may narrow the tropical climate zones, expanding polar climates.

    Do you live on the fringe of a polar or tropical climate?

    That may change.

    Have you felt that change lately?

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  90. John Norris

    Reading Kerry Emanuel’s post is painful. He put together a useless analogy to give credit to his point. It discredited it for me.
    – mitigating the risk of crossing the street is very inexpensive, and managed by leaving for the bus stop a little earlier
    – mitigating the risk of global warming is a trillion dollar expense, and keeps third world countries in a third world footing for several more generations
    The two have very different levels of cost verses risk.

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