RealClimate logo


Predictable and unpredictable behaviour

Filed under: — rasmus @ 13 March 2017

Terms such as “gas skeptics” and “climate skeptics” aren’t really very descriptive, but they refer to sentiments that have something in common: unpredictable behaviour.

Statistics is remarkably predictable
The individual gas molecules are highly unpredictable, but the bulk properties of the gases are nevertheless very predictable thanks to physics. More specifically the laws of thermodynamics and the ideal gas law.

The bulk aspects of the gases are a result of the statistical properties of a vast number of particles. Statistics is surprisingly predictable even if the individual cases are not.

Just look at Las Vegas and the insurance industry which make a living on the fact that probabilities (statistics) are predictable. Even economists pin their hope on statistics, and the medical sciences would never be where they are now without the predictive power of statistics.

A “gas skeptic” would say that you cannot predict the state of the gas because the molecules are unpredictable. This is analogous to saying that climatic states cannot be predicted because the weather is unpredictable (a “climate skeptic”).

Climate is weather statistics
Climate can be viewed as weather statistics. Early climatological work was dedicated to survey of how the weather statistics varied from place to place and over the seasons.

There are clear effects of physical factors (latitude, mountains, distance to the coast) on the statistical character of the weather and the weather statistics (climate).

In other words, the statistical properties are a result of the physical processes and conditions present and are readily predicted from e.g. geographical factors, seasonal variations in the solar inclination, the atmospheric composition and the planet’s distance to the Sun.

The weather statistics (eg probabilities) are predictable in spite of the chaotic and nonlinear character of weather itself.

Common misconceptions
There are some examples where the question about predicting the exact state is mixed up with the question of predicting the statistical properties of the system, even by people with some experience in climate research.

Some of them are useful for further learning, and there is a number of them in a ‘report’ (“Climate models for the layman”) that Judith Curry has written for a British interest group that calls itself “GWPF”.

Curry’s report has also been used to back Norwegian contrarians who support the effort of a populist politician to get a seat in the parliament.

The analogy to a “gas skeptic” above illustrates why Curry’s claim is misconceived because it is false that the climate models are unfit to make predictions about the future climate just because the atmosphere behaves in a nonlinear fashion due to the Navier-Stokes equations.

The Navier-Stokes equations describe the atmospheric flow (winds), but the key equations for climate change involve the laws of thermodynamics and the way the different gases absorb different frequencies in the electromagnetic spectrum.

The most important nonlinear component in this respect include scattering processes, phase transitions, and cloud formation.

A potential feedback paradox
Curry also introduces a potential paradox in her report when she emphasises natural variations. The magnitude of natural temperature variation are regulated by feedback processes and have physical causes. The climate sensitivity also involve such feedback processes.

Any feedback process based on temperature will act on both natural and forced changes in the temperature. If such feedbacks result in pronounced natural temperature variations, they also imply that the climate sensitivity is high.

Examples of such feedbacks include increased atmospheric humidity and reduced snow/ice cover. Processes involving clouds are more uncertain, but they too are likely to be affected by temperature (convection) and act to modify the climatic response.

Natural variations may arise from both variations in the climatic state (eg ENSO, NAO, and PDO) or from external causes, such as changes in the sun and volcanic eruptions.

There are also feedbacks relevant to forced variation as well as internal variability which don’t always mean that higher amplitude natural variability necessarily indicates greater climate sensitivity.

For example, the fact that there is enhanced variability in the 3-7 year ENSO band is a result of climate dynamics (Bjerkenes feedbacks) resonating with wave propagation timescales.

Other examples include distinct oscillatory models of variability with decadal and longer timescales, related also to oceanic Rossby wave propagation and gyre spinup processes, or timescales associated with the AMOC.

It is possible to get enhanced variability on those timescales as a result of dynamical mechanisms without needing to appeal to higher climate sensitivity.

Nevertheless, the bottom line is that Curry must prove that the feedbacks involved in the natural variations are different to those affecting the climate sensitivity before she can conclude that natural variability dominates over a warming due to increasing greenhouse gases.

It’s not the sun
When Curry believes that the changes in earth’s temperature are due changes in the sun, it is important to keep in mind that the variations in the sun only affect as a small fraction of earth’s energy input. Amplifying feedback processes are needed to explain the magnitude of the observed changes.

Curry makes a point of the temperature increase before the 1940s, and that the CO2 concentrations were low then. But she seems to have forgotten that the forcing is proportional to the logarithm of the concentration: the effect of an increase is initially higher with lower concentrations.

The changes in the climate before 1940 were a result a combination of factors when there was an increase in the number of sunspots that coincided with increasing CO2-concentrations.

It is well-known that the sunspot record suggests an increase up to the 1950, but various solar indicators indicate no long-term trend in the sun since the 1950.

Only the increase in the greenhouse gases can explain a forced warming since the 1950s because no other physical forcings exhibit long-term trends since then.

Problematic statistics
Another issue is that early temperature record does not give as complete global data coverage as more recent measurements. The global temperature analysis is based on smaller sample in the early part, for which we expect to see stronger random sampling fluctuations.

This is consistent with what Figure 4 in Curry’s report shows. However, she misinterpreted this as being strong natural variability in the early part of the record.

Curry also makes the same mistake as John Christy by using the ensemble mean as a yardstick for the models (here): model evaluations must be based on the individual simulations taking into account the spread of the ensemble run.

It’s not just the temperature
The climate sensitivity is one indicator for the consequences of a global warming which only accounts for the change in temperature, but it is important not to ignore that changes in the global hydrological cycle may also have a severe impact on society.

It is possible that a weaker temperature increase is associated with a larger shift in the convective activity and more pronounced changes in the rainfall patterns (Benestad, 2016).

The comprehensive picture and consistency
I often find it useful to look at the comprehensive picture in science and look for consistencies, both when it comes to physics and the logic.

A curious twist in Curry’s report is (a) her claim that climate models have exaggerated climate sensitivity because they did not reproduce the observed warming over the 2000-2015 period and then (b) her emphasis on natural variations having scales of “weeks, years, decades, centuries and millennia”.

If the claims hypothetically were correct, then how would she know that the temperature variations over brief intervals are not just a result of the natural variations that she emphasised?

We should expect some brief periods with both rapid as well as slow warming (Easterling and Wehner, 2009), and some of the model simulations have indicated a weak warming over the same period. This is explained in the IPCC AR5 (Box 9.2).

Another question is whether the warming rate reported by the AR5 was correct, and more recent studies suggest artificially weak warming connected to changing observational networks (Karl et al, 2015). This has been discussed here. Hence, Curry’s claim about slower warming rates has lost substance.

Surprising
There is a curious remark in Curry’s report about the climate models’ inability to match the phase and timing of the natural variations. Yes, it is true, but it is also a well-known fact.

The way it is stated in the report makes me think that Curry has not understood what the climate modelling community is trying to do, however. My suspicion is strengthened when she makes a point about the model simulations not including future changes in the sun and volcanic eruptions.

The elementary misconceptions revealed by Curry’s “Climate Models for the layman” surprise me. Does she really not understand the flaws presented here or is she trying to sow confusion?

References

  1. R.E. Benestad, "A mental picture of the greenhouse effect", Theoretical and Applied Climatology, vol. 128, pp. 679-688, 2016. http://dx.doi.org/10.1007/s00704-016-1732-y
  2. D.R. Easterling, and M.F. Wehner, "Is the climate warming or cooling?", Geophysical Research Letters, vol. 36, 2009. http://dx.doi.org/10.1029/2009GL037810
  3. T.R. Karl, A. Arguez, B. Huang, J.H. Lawrimore, J.R. McMahon, M.J. Menne, T.C. Peterson, R.S. Vose, and H. Zhang, "Possible artifacts of data biases in the recent global surface warming hiatus", Science, vol. 348, pp. 1469-1472, 2015. http://dx.doi.org/10.1126/science.aaa5632

218 Responses to “Predictable and unpredictable behaviour”

  1. 51
    Mike Flynn says:

    Tamino,

    I repeat – “The WMO definition – “Climate, sometimes understood as the “average weather,” is defined as the measurement of the mean and variability of relevant quantities of certain variables (such as temperature, precipitation or wind) over a period of time, ranging from months to thousands or millions of years.” The IPCC uses the same definition in its glossary.”

    Your definition – “Climate is the probability density function of weather.”

    Dodging around by blaming me for definitions provided by the WMO and IPCC won’t make the definitions go away. They are what they are.

    Again, from Wolfram –

    “However, it should be noted that despite its “random” appearance, chaos is a deterministic evolution.” Do you understand the difference?

    As to a tossed coin, you still can’t predict the outcome of the next toss based on past behaviour, can you? Trying to divert the conversation with irrelevancies won’t change my assumption that the future is unknowable, in any any useful sense. But you are firmly convinced that you can predict future climate, or climate states, by examining the past.

    The problem is that you need to predict the future of climate (or even weather) better than I can. And neither you, nor anybody else can do better than a reasonably intelligent 12 year old, with 30 minutes instruction relating to naive persistence forecasts.

    By the way, you noted I posited a “fair” coin. Maybe I should have posited an “ideal” coin, as – “In theoretical studies, the assumption that a coin is fair is often made by referring to an ideal coin.”

    Of course, an actual physical coin could be carried off by a seagull, fall into a crevasse, land on its edge, spontaneously combust and so on. As a statistician, you would appreciate the probability of a coin providing neither a clear head or tail as being remote, but possible.

    My fair coin is an ideal one. Of course, people spout nonsense about a fair coin producing equal amounts of heads and tails over a sequence of throws. They are guaranteed to be wrong at least 50% of the time – any odd number cannot be evenly divide by two. Actually, the longer the sequence, the greater the discrepancy may be. You may care to provide the probability of a sequence of say, 11 heads in a row, in a sequence of 1,000,000 throws.

    It will be assuredly greater than that of a sequence of 10 throws, where the possibility of 11 results of any sort is impossible.

    But no matter, neither you nor anybody else, can even usefully predict the result of the next throw. It may be a head, it may be a tail – or it may be neither. You’re no better off.

    And still you claim that future atmospheric states can be predicted by examining history. Palpable nonsense, I say!

    Cheers.

  2. 52
    Mike Flynn says:

    PRoUK AntiTheism,

    Not good enough. Analogies are much beloved of GHE supporters, but usually irrelevant and pointless. Assumptions about the future are all well and good. I assume the Sun will rise again tomorrow, and I’ll still be here to enjoy it.

    According to the IPCC, predicting future climate states is impossible. Easy enough to accept – even a person who is apparently “one of the foremost statisticians in the country, . . . ” cannot predict the result of the next throw of a coin.

    In the meantime, try and raise the temperature of a thermometer by interposing CO2 between the thermometer and a heat source. How hard can it be?

    I’ll save you a little time and effort if you wish. John Tyndall did well documented work over 100 years ago which showed that the more gas between a heat source and a thermometer, the less heat reached the thermometer, and the temperature dropped as a consequence. Some gases intercepted much more energy than others, and the temperature drop was of course more pronounced.

    No GHE. Just the opposite. Sorry – but read his publications if you don’t believe me. I would recommend a later copy, as Tyndall made corrections on the basis of new knowledge as footnotes. I assume it saved the cost of resetting and imposition, which needed to be done manually.

    Cheers.

  3. 53
    Mike Flynn says:

    Thomas,

    You wrote –

    “#40 Mike Flynn, “What’s wrong with a very long term average?” You tell me. iow Prove ur genuine and not another delusional irrational flake with an internet connection. :-)”

    I just asked a question. Why do I have to prove anything to you?

    If you can’t or won’t answer, that’s your affair. If you choose to believe in the impossible, that’s also your affair. I’m a non believer in the thermometer heating properties of CO2. A cylinder of 100% CO2 in a cold room at -4 C is the same temperature as everything around it after a few hours.

    You may choose to believe otherwise if you wish.

    Cheers.

  4. 54
    Thomas says:

    53 Mike Flynn: “I just asked a question. Why do I have to prove anything to you?” – “What’s wrong with a very long term average?”

    If you’re up for an intelligent mature discussion then you need to prove to me you’re up to it or I will not engage. That’s why. It’s not a direction it’s an invitation. :-)

    I’m operating on the basis that if you are genuine, intelligent and mature then you would already know many or most of the limitations of what COULD be WRONG with using very long term averages. Where, when and why that is so. As well as where, when and why very long term averages COULD be USEFUL.

    Apparently you have no idea. Which answers my question succinctly. See? I do not believe in the impossible, such as having an intelligent mature or genuine discussion with you. Thanks.

  5. 55
    Mike Flynn says:

    BPL,

    There is no 200 years of relevant science. So yes, anyone who claims that the temperature of a thermometer can be raised by placing CO2 between the thermometer and a heat source is quite simply flying in the face of physics. Use your favourite radiative transfer equations and try to show a temperature rise as you remove energy by placing anything except a vacuum between source and target. You can’t, of course.

    The surface temperature of a planet is established by measurement. The surface temperature of the Earth, for example, was above the melting point of rock. Sometime later, it was below that, but above the boiling point of water. Later on, it was low enough for liquid water to form, but above freezing point. And so on.

    The Earth is still more than 99% molten.

    You can no more calculate a planetary surface temperature than you can calculate the surface temperature of my coffee. It’s above freezing, below boiling, and cooling.

    Your suggestion of the usual pointless “experiment” does not demonstrate any heating due to CO2. Rather, it demonstrates that the application of sufficient heat to a thermometer will cause it to get hotter. It’s about as relevant as showing that a highly radiation absorbent object will heat faster than an object not so absorbent. Both boxes will be exactly the same temperature when allowed to reach equilibrium. CO2 at any temperature is precisely the same temperature as another gas, liquid or solid at that temperature. One might just as well claim that black objects are always hotter than white objects.

    The specific heat of the gas will influence the rate at which the temperature changes. Left alone, all matter will radiate all its excess energy away, and reach absolute zero. Even CO2! No heating there!

    May I point out that the Sun becoming a red giant has little to do with the supposed GHE. Are you inadvertently trying to deny, divert, and confuse? After four and a half billion years of sunlight, the Earth has still cooled! Still cooling, even, unless you can find a way to flout the laws of thermodynamics.

    CO2 heats nothing.

    Cheers.

  6. 56
    Astringent says:

    #51 Mike Flynn

    It’s not complicated. Take your ideal coin. Heads is a warm day. Tails a cold day. Flip the coin, and you don’t know whether the day is warm or cold until the coin lands. Flip it 365 times, it should give us a nice average year.

    Repeat – the year’s remain average. I don’t know whether day 200 of year 25 will be hot or cold, but I can predict that over the whole year it will balance out close to ‘average’.

    Now repeat your experiment, but this time at the end of each year shave a bit of metal off one side of the coin – so each year the coin is a little less ideal. So now it’s not a 50:50 call, maybe its 50.1:49.9.

    Observe the trend as the coin gets increasingly non-ideal. I still can’t predict day 200 of year 25, but I might be able to predict the new ‘average’.

    (and you do know it’s about shining radiation through a gas, not keeping it in a cylinder….?)

  7. 57
    t marvell says:

    Curry makes the mistake of comparing changes in CO2 levels with changes in temperature during the same period. There is a lag caused by, among other things, feedback loops and oceans absorbing CO2.

    Just what is the lag? Comparing historical CO2 carbon emissions and temperature increases suggests a 20-30 year lag. For example, lower emissions during the 1930’s depression and slow growth in the 1940s is followed by little temperature growth in the 50s, 60s, and 70s. The post-war increase in emissions is followed by rather steady temperature increases starting about 1980. This is a crude comparison. Do climate models give a better estimate of the lag?

  8. 58
    Mike Roberts says:

    Flynn: “And still you claim that future atmospheric states can be predicted by examining history. Palpable nonsense, I say!”

    That would be nonsense, on its own. But we also know why the history has occurred and what is likely to be the situation in the future (e.g. the effects of increasing GHG concentrations can be estimated from past data plus the science of GHGs and GHG concentrations look likely to continue increasing). So history gives a guide to what we can expect if we continue to pour GHGs into the atmosphere.

    Your replies seem to suggest that we should ignore the knowledge we’ve accumulated about the effects of various factors on climate and, instead, just take each day as it comes and hope for the best.

  9. 59
    Leto says:

    Guys, has it occurred to you that Mike Flynn is simply not worth your time? How many dumb statements can one guy make, and still be taken seriously? (That’s rhetorical, but of course the answer is 42).

  10. 60
    Leto says:

    Tamino,

    I think your conception of climate as the probability density funciton of weather is essentially correct, and certainly an improvement on simplistic notions of “average” weather. (Clearly, a climate that alternated between days of zero degrees C and 20 degrees C would not be the same as one that was consistently 10 degrees). The IPCC definition (cited by MF, godblessim) adds the term “variability”, which is a general hand-wave in the direction of the probability density function – presumably, the IPCC have dumbed some things down for general consumption.

    The only problem in defining climate in terms of weather that I see is that “weather”, in common parlance, has an anthropocentric emphasis. Weather is what we experience when we wander outside and does not fully encompass the full scope of climactic variuables such as temperatures in the deep sea, high altitude winds, and so on.

    BTW, good to have signs of life from you, been missing your blog posts.

    Cheers, Leto.

  11. 61

    MF 150: GHE supporters overlook the fact that the Earth is more than 99% molten, and thus has a surface temperature greater then zero.

    BPL: Flux density at the Earth’s surface from sunlight: 161 Watts per square meter. From atmospheric back-radiation: 324 W m^-2. From geothermal sources: 0.087 W m^-2. Add A to B. Divide by C. Discuss.

  12. 62

    MF 152: John Tyndall did well documented work over 100 years ago which showed that the more gas between a heat source and a thermometer, the less heat reached the thermometer, and the temperature dropped as a consequence.

    BPL: Right. Now assume that the heat source is the ground.

  13. 63

    MF 53: I’m a non believer in the thermometer heating properties of CO2.

    BPL: You can be a non-believer in evolution, in relativity, in quantum mechanics–whatever you want. Your statements on the subject here show you have no idea how the greenhouse effect is even supposed to work, so your criticism of it is very like that of a creationist, who knows no biology, critiquing evolution. I asked you how a planet’s surface temperature was determined. You never answered. I take it you don’t know. So until you do know, why don’t you bow out of the conversation for a while and do some studying? I can recommend good textbooks on the subject.

  14. 64
    angech says:

    “BPL: It’s a standard experiment. You shine a sunlamp on one box with regular air, one with pure CO2, each with a thermometer in it. It goes higher in the one with the CO2.”

    Are you sure?
    Experiment should be
    . You shine a sunlamp on one box with regular air, one with no CO2, each with a thermometer in it. Your claim should be “It goes higher in the one with the CO2 (regular air)”.

    Your example is poorly stated , how much pure CO2? Very important . What pressure. Is the box translucent , does it have a base?

    I would merely point out that a source of energy giving heat to a box containing a gaseous substance and a thermometer will possibly give only one temperature reading, that of the temperature source at that distance.
    Flynn may be right.
    Non GHG will let the full effect through to the thermometer. GHG will heat up til it transfers the heat it has blocked from the thermometer to the thermometer but no more. In fact if it is radiating the heat back it might even reduce the temperature of the thermometer! You could “shield” the thermometer to just get the air temperature but that is interfering with the experiment. Or you could measure the radiation from the box. The IR would be higher with more CO2, the air is “warmer” but a thermometer in the box would not have gone up.

  15. 65
    Gordon Shephard says:

    Mike@all those places

    I agree with you that you cannot predict the results of the next coin toss. You can, however, predict that the result of the next 1000 coin tosses will be something close to 50/50 heads/tails, and that however far from 50/50 that result may fall, the more times you toss the coin, the closer it will get. And, further, that if the ratio is not approaching 50/50, you would be justified in claiming that the coin is rigged.

    The IPCC says that future climate states (weather) cannot be predicted, but that does not mean that you may not state the probability for what the average of future climate states will be.

    Mike, YOU cannot predict future climate states either. You’ve placed your bets but, as a hedge, you might want to invest in ice.

  16. 66
    SteveP says:

    Report to Miscommunication Directorate: The МАЙК ФЛИНН (Mike Flynn) operative has successfully managed to tie up great quantities of people’s productive time with inane babble about climate change. The naive tendency of science types to engage with our operatives in this forum has resulted in untold quantities of wasted time and effort by the enemy. Good job.

  17. 67
    Vendicar Decarian says:

    #1 – “Tell someone that their particular version is doomed, and they will fight you tooth and nail.”

    That is an exceptionally good observation.

  18. 68
    MA Rodger says:

    Mike FLynn @50.
    We can conclude that you are not here to discuss the issue of the ‘predictability of future climate’ but instead have come to wave your denialist views at “GHE believers” (whatever a GHE believer is).
    ☻ I will assume from your saying “GHE believers avoid addressing the subject at all costs” that you feel your comment @7 has not been “addressed.” Thus, concerning what you should and should not know, while you probably will deny that AGW is a problem for mankind because you “know” otherwise, do you also deny the existence of comment #14 up-thread? And do you also deny the existence of comments #20, #21 & #22? If so, why would you do that?

    ☻ Concerning the IPCC TAR quote, please note that you do directly misquote it. You also misinterpret it, a situation as is plain as day to anyone who is interested enough to read past the few words you lay such store by.

    ☻ And I note you are unable to differentiate between discussion of ‘chaos’ and discussion of ‘random behaviour’. Perhaps if you look, you will find that @41 I do not suffer that confusion. Indeed, confusion appears to be a problem for you. Have you really meaningful reason to suggest that Gavin Schmidt (one of our hosts) “believes that the IPCC is Wrong”? Or is this more of your confusion?

    ☻ And may I repeat the final point I made @41. The level of molten rock on the early Earth is not properly a matter of climatalogical interest. And may I add that your (over)estimate of the proportion of the panet’s mass which is today “molten” is also not a matter of climatalogical interest.

  19. 69
    Vendicar Decarian says:

    51 “And still you claim that future atmospheric states can be predicted by examining history. Palpable nonsense, I say!”

    Stupid people say many stupid things.

    You are confusing a discrete, quantized, and uncorrelated system (coin) with a continuous, correlated time series.

    You defined your coin to be “fair” which is equivalent to claiming that there is no correlation between the results of the flips.

    The climate system on the other hand is correlated. The system evolves from one instantaneous state to another in a continuous manner. This necessarily means that by selecting a value of delta t small enough, a measured state of the system at time t+(delta t) comes arbitrarily close to the measured state at time = t.

    It is self evident that the state of the global climate now is practically the same as the state 1 second from now, or 1 millionths/billionth/trillionth of a second from now.

    Your “belief” is therefore founded on nonsense since your “belief” is obviously false for values of delta t that are sufficiently small.

    Times that small are of course completely unnecessary. Thre is exceptionally good correlation between weather conditions on any given day in the year, relative to the correstponding day in any other year and certainly since the end of the last ice age.

    Summer days are warmer than winter days, spring and fall days tend to be cooler. This correlation from year to year is very strong, and it is apparently something that you do not “believe”.

    Climate is of course, also constrained by the laws of physics. The Earth tomorrow can not suddenly have twice the surface temperature it has today. To do that, solar output would have to change dramatically, and that can’t happen due to the fact that photons take something on the order of 100,000 years to diffuse from the core of the sun to the sun’s surface, and then to the earth’s surface.

    An instantaneous change in the core of the sun, will not be seen at the solar surface for many tens of thousands of years, and then only as a change that is smeared out over thousands of years.

    Bulk systems in thermal contact move toward equivalent temperatures. This is a basic law of thermodynamics. It is therefore impossible for ocean temperatures and atmospheric temperatures to seek a non-equilibrium state. So we know that if they are n’C apart today they will be less than n’C apart tomorrow all other things being equal.

    So your “belief” also fails a basic science literacy test.

    Finally you quote…

    “However, it should be noted that despite its “random” appearance, chaos is a
    deterministic evoluion.”

    and then ask…

    ”Do you understand the difference?”

    You are also suffering from a failure to understand chaotic systems.

    Chaos is not randomess. Tossing a fair coin produces a random result as it produces a system without any correlation.

    Chaotic systems are not random, and show correlation between states. It is this correlation that permits the system to evolve in a practically unpredictable manner, as the state at time t influences the state at time t +(delta t).

    A dripping faucet is a common example of a chaotic system. In this instance, the size and shape of the water on the spout left over after a drip, influences when the next drip will leave the spout.

    Plotting the state of chaotic systems, does not show simple randomness, but shows that the system state typically clusters around one or more fixed points. If the system is non-discrete then the state of the system moves continuously in a path around those fixed points.

    The precise state of such a system can only be computed forward for a short period of time before the system’s sensitivity to initial conditions causes it to evolve away from the predicted value. However, the system is still bound to the fixed points around which it evolves.

    Chaotic systems then are more predictable than simple randomness, and in fact the set of attractors for the system precisely defines some measure of the average state of the system.

    When it comes to climatology, taken over sufficiently long time periods the system attractors are essentially the climate, while the exact position of the system in the orbit around the attractor set, is the weather.

    Your “belief”, like most beliefs and all denialist beliefs, is based on pure ignorance.

  20. 70
    Vendicar Decarian says:

    Re:2 “The ideal gas law gives a specific answer, and repeated tests confirm that accuracy of the predictions within the range of experimental error.”

    Did it even occur to you that the “ideal gas law” is for ideal gasses, and that no gas is “ideal”.

    We most certainly could express a new gas law in terms of the probability that the state of a random gas will be in a state within some distance from the predicted value.

    We don’t do this, because doing so has no applicability in the real world.

    In the real world we produce new functions for each gas that embody the primary ways in which they physics of that gas changes with changes in V,P an T.

    Doing this requires estimates of how the gas interacts with itself, and with it’s container, and is far more precise than specifying a statistical distribution of potential states.

  21. 71
    Vendicar Decarian says:

    Re: 3 “a rapid transition from scientific badge of honor”

    Being a skeptic has never been a badge of honor in the scienific community.

    Who lied to you and told you otherwise?

    Why were you so easily fooled?

  22. 72
    Vendicar Decarian says:

    Re:5 “This may be a legitimate explanation, but if the models were wrong in the past, that provides ammo to believe they may still be wrong.”

    If the public is too ignorant to understand the difreence between wong and W.R.O.N.G!!!! then there is little that can be done, because the failure is their failure to understand how science works.

    Most American Republicans can not add or subtract without a calculator.

    It is not possible to explain error, and statistical confidence ranges, to Neandertals, and factory farm animals.

  23. 73

    MF 55: There is no 200 years of relevant science.

    BPL: Look again.

    http://bartonlevenson.com/ClimateTimeLine.html

    MF: So yes, anyone who claims that the temperature of a thermometer can be raised by placing CO2 between the thermometer and a heat source is quite simply flying in the face of physics. Use your favourite radiative transfer equations and try to show a temperature rise as you remove energy by placing anything except a vacuum between source and target. You can’t, of course.

    BPL: You’re missing the point. The CO2 doesn’t amplify the light or create light of its own. It prevents the thermometer from losing IR light. Like a blanket.

    MF: The surface temperature of a planet is established by measurement.

    BPL: I didn’t ask you how to measure it. I asked what determines it. What are the physical processes that determine a planet’s temperature? Do you know?

    MF: You can no more calculate a planetary surface temperature than you can calculate the surface temperature of my coffee. It’s above freezing, below boiling, and cooling.

    BPL: That’s just wrong. Any physical object in local thermodynamic equilibrium has a measurable temperature. Are you trying to tell me we don’t know if Venus is hotter than Pluto?

    MF: Your suggestion of the usual pointless “experiment” does not demonstrate any heating due to CO2. Rather, it demonstrates that the application of sufficient heat to a thermometer will cause it to get hotter.

    BPL: Why does the thermometer in the box with CO2 get hotter than the thermometer in the box with air, Mike?

    MF: It’s about as relevant as showing that a highly radiation absorbent object will heat faster than an object not so absorbent. Both boxes will be exactly the same temperature when allowed to reach equilibrium.

    BPL: No, they won’t be. Do the experiment yourself.

    MF: CO2 at any temperature is precisely the same temperature as another gas, liquid or solid at that temperature. One might just as well claim that black objects are always hotter than white objects.

    BPL: Again, you’re assuming that I think CO2 is somehow a source of independent energy. I didn’t say that, and once again, you don’t understand the theory you’re criticizing.

    MF: May I point out that the Sun becoming a red giant has little to do with the supposed GHE. Are you inadvertently trying to deny, divert, and confuse?

    BPL: No. Are you deliberately being hostile, aggressive, and unpleasant?

    MF: CO2 heats nothing.

    BPL: CO2 surrounding a planet keeps the planet’s surface warmer than it would otherwise be.

  24. 74
    Michael Flynn says:

    Astringent,

    I haven’t the faintest idea what you are talking about. You say you might be able to predict a new average. Or you might not, conversely. Not complicated at all. I agree. Just pointless.

    Sorry, but tossing coins to defend the non existent GHE seems a bit odd.

    Cheers.

  25. 75

    Mike Flynn shows all the signs of being troll of the sea lion variety, going out of his way to reject even the best and clearest explanations as gibberish, yet showing sufficient knowledge to indicate that he is smart enough to know better.

    If you’re not familiar with the term “sea lioning,” here’s an explanation: http://knowyourmeme.com/memes/sea-lioning

    I recommend not feeding the troll.

  26. 76
    ChemEng says:

    The behavior of a gas is never expressed in statistical terms. This is because the gas law is well understood and there are simple equations that can be used to determine temperature, pressure, volume, etc…..
    The same can’t be said for modeling climate. To imply that climate can be modeled to the same degree of accuracy as any thermodynamic gas law is complete bunk. Apples and oranges.
    This is an inane comparison at best.

  27. 77
    George says:

    I would think the planet Venus would be a better experiment, which has already been conducted.

  28. 78
    nigelj says:

    Mike Flynn: “So yes, anyone who claims that the temperature of a thermometer can be raised by placing CO2 between the thermometer and a heat source is quite simply flying in the face of physics.”

    This is a deceptive strawman argument. Obviously its technically true taken literally as in a wall of gas between just a thermometer and a heat source.

    But put that thermometer in a container in a room, and ensure it is completely surrounded by Co2, and provide a lamp, it will heat up. We know this because of simple lab experiments. This is the greenhouse effect.

    Mike Flynn either doesn’t comprehend this or knows full well, and is deliberately being deceptive. Some people are warped, sneaky and poisonous.

  29. 79
    Leto says:

    Hah, forgive the Freudian typo @60: climatic->climactic.

  30. 80
    Vendicar Decarian says:

    MF: CO2 heats nothing.

    CO2 backscatters long wave photons back towards the Earh’s surface which is their place of origin.

    As a result the surface of the Earth is warmer than it would be if the CO2 were not present.

    This is simple grade school science.

    What is your excuse for not understanding it?

    Maybe you could rent an 8 year old and have them explain it to you.

  31. 81
    Stephen Eshbaugh says:

    It saddens me deeply to see folks still getting into the weeds with posters who simply are trying to obfuscate and confuse. The evidence is so clear that anyone who has done field research has witnessed disquieting changes in animal and plant populations. Climatologists have statistically significant evidence of a rapidly warming planet, caused by humans. I strongly recommend nobody engage with another who claims carbon dioxide does not warm the planet. You never will reach such a person.

    I would very much like to see the discussion switch to one where there are suggested actions climate researchers would like to see become a reality to ensure this planet is still livable when my now 13-year-old son lives into his 80s.

  32. 82
    Vendicar Decarian says:

    “When it comes to climate change, the president

    Regarding the question as to cliamte change, I think the president was fairly
    straight forward.

    We’re not spending money on that any more.

    We consider that to be a waste of your money to go out and do that. So that
    is a specif tie to his campaign.” – Mick Mulvane white house budget director
    March 16, 2017

  33. 83

    CE76: To imply that climate can be modeled to the same degree of accuracy as any thermodynamic gas law is complete bunk.

    BPL: You’re aware that the ideal gas law doesn’t actually apply very well to many gases, aren’t you? And how accurate do climate models have to be to predict that pouring more greenhouse gases into the air will heat the surface?

    “I don’t have to outrun the leopard.”

  34. 84
    patrick says:

    Mike Flynn: Very sorry, but you are missing the point. It’s about probability.
    Of course you can’t predict a toss. That’s not what this is about. As Rasmus says in the post, in plain language,”Statistics is surprisingly predictable even if the individual cases are not. Just look at Las Vegas and the insurance industry which make a living on the fact that probabilities (statistics) are predictable.”

    Thanks, Rasmus, for being so comprehensive, helpful, and relevant.

  35. 85
    Mr. Know It All says:

    81 – I agree with this. I am aware of 2 or 3 methods (other than eliminating FF use) that may reduce CO2 in the atmosphere. One would be pumping CO2 into the ground and turning it into rock. Another would be using sodium hydroxide to absorb CO2. There is one using soil also. And we might plant more trees, etc.

    But before we start crunching the numbers and earning our keep, who can win the contest in guessing which famous climate scientist most resembles the singer in this video:
    https://www.youtube.com/watch?v=YH5Arbm47IQ

    :)
    3/17/2017 @ 1:27 AM pacific

  36. 86
    MA Rodger says:

    The bizarre ideas of Mike Flynn concerning climatology found their way to the Bore Hole. Perhaps to rescue one thought from there which by parts does lead back to the topic of this thread.

    One of the grand reasons for AGW denial that ended up adorning the Bore Hole was his idea that the hottest places on Earth are deserts, places with the least overhead cover of GHGs. So, a naive person may argue, where there is least GHG cover is where temperatures are hottest. Ergo, GHGs cannot be effective and any theory which says otherwise (eg AGW) has to be fatally flawed.
    A sneak view of a global temperature map might lend support for such a view (if you ignore places like India or Indonesia or the Central Americas because they would certainly also be desert if the rains failed). Indeed Wikithing puts the hottest inhabited place on Earth as Dallol, Ethiopia which may be sited below sea-level in the Danakil Depression but it is undoubtedly very deserty.
    Yet a more complete map would show the whole planet, land and ocean, and such a map shows that without the land masses to effect the situation, the warmest places are over the Equator, and that despite all the rain.

    Of course, climatology usually plots out temperature anomalies rather than absolute temperature and I note the Wikithing page that lists extreme places like Dallol, Ethiopia also sports such a global map showing 2015 anomalies (as I write, that Wikipage is still reporting 2015 as the warmest year on record). The blue patterns on that map reminds me very much of the discussion paper Hansen et al (2016) ‘Ice melt, sea level rise and superstorms: evidence from paleoclimate data, climate modeling, and modern observations that 2ºC global warming could be dangerous’ which certainly describes a different prediction for this coming century. Now there is a prediction worthy of discussion.

  37. 87
    ChemEng says:

    BPL83 : You’re aware that the ideal gas law doesn’t actually apply very well to many gases, aren’t you?

    …and it still outperforms climate models. It benefits from minimal uncertainty in the inputs and the characteristic of being able to have repeatable experiments conducted. We know the temperature, pressure and molecular weights exactly. Climate models have an infinite number of input combinations and possible lump parameterizations – none of which have less uncertainty than the gas law inputs…. and we all know that repeatable experiments aren’t possible. It’s still a ridiculous comparison.

  38. 88
    Leto says:

    Guys,
    Brian @75 is spot on. MF’s arguments are so poor it is doubtful that even he believes them. He is simply dragging the thread away from sensible discussion and wasting everyone’s time and energy.

  39. 89
    Jim Eager says:

    There is an appropriate place for people such as Mike Flynn. It’s called The Bore Hole.

  40. 90
    Mal Adapted says:

    Stephen Eshbaugh:

    I would very much like to see the discussion switch to one where there are suggested actions climate researchers would like to see become a reality to ensure this planet is still livable when my now 13-year-old son lives into his 80s.

    Beyond “get everyone to stop transferring carbon from geologic sequestration back to the climatically-active pool”? How much detail do you want?

    Seriously, Mr. Eshbaugh, discussion on RC is nominally limited to the physical manifestations and mechanisms of anthropogenic global warming. If you stick around long enough, though, we’ll occasionally get pretty far off into the economic and political weeds. We all have opinions, naturally, and some of us will even claim ours are supported by facts.

  41. 91
  42. 92

    CE 86: Climate models have an infinite number of input combinations and possible lump parameterizations

    BPL: Infinite? Really? Is someone going to model the Earth as having an atmosphere with a total mass of 3 kilograms, or a surface area of 22 square light-years? Or say the atmosphere is 52% oxygen and 48% methyl picrate? Maybe that the surface emissivity is 150%?

    CE: none of which have less uncertainty than the gas law inputs…. and we all know that repeatable experiments aren’t possible.

    BPL: That’s why we write models, and examine other planets, and look at Earth in the past. Repeatable experiments aren’t possible with stellar evolution, either, but do you dispute that main sequence stars become red giants?

    CE: It’s still a ridiculous comparison.

    BPL: Only to someone like you who is outside the field but thinks they can understand it because they know another, completely different field.

  43. 93
    Leto says:

    MF has inspired me to read about sealioning… The end result is that I think he does not quite fit the profile. His modus operandi is not to ask polite-sounding questions and ask for references, but rather to strike out with obvious fallacies and then let everyone succumb to the natural temptation to correct those fallacies. The more obvious the flaws, the greater the temptation.

    So, he is some other from of troll. I don’t claim to be an expert on troll taxonomy, so maybe there is already a term for this species of trolling. If so, what is it? If not, perhaps we should call this form of trolling the narwhal. That is, like a sealion in intent, but generally a bit pointier.

  44. 94
    M. Passey says:

    This post illustrates my basic question of how climate models fit into the scientific method.

    Medical sciences are where they are because of the predictive value of experimentally obtained data. All of the laws of physics have been obtained by describing experimentally obtained data mathematically. The information is in the data. The scientific proposition in making a climate model is that if the input is known laws of physics, the output will describe physically reality. It is frequently said that we don’t need climate models to know that increasing CO2 will cause global warming, because we know the basic physics. This is quite true, because a computer algorithm cannot generate observational data from the physical world. The output has the same data-based information content as the input formulas (ignoring parameterizations here). The problem with this is illustrated by the ideal gas law. Because gases aren’t ideal there are times where the ideal gas law doesn’t describe reality closely enough for a given purpose. There are plenty of times where it absolutely appropriate to be a gas skeptic. If you want to propose that a climate model can formally add information beyond the known basic physics you have to prove that your inputs are fit for that purpose. For example, if you have a hypothesis that a climate model can add quantitative information about future temperature response to increasing CO2, your null hypothesis is that future global temperature is unpredictable. Your model then has the same requirement as any other mathematical description of physical phenomena. It has to reject the null hypothesis by prospectively tracking out of sample global temperature closely enough for your stated purpose.

    @BPL 92. I know that a tremendously high percentage of the “skeptical” posts here are complete dross that you get tired of responding too. But it seems to me that sometimes people with operational understanding of study design and statistics from other research areas come along and ask valid questions about climate modeling. I think ChemEng is basically saying that you can’t prove the validity of your model output by invoking the validity of the input. If anything, the analogy of “gas skeptic” to “climate skeptic” demonstrates this point, if his claim is correct that climate model inputs inhere more uncertainty than even the simple idea gas law. So, I genuinely ask you, where is my reasoning wrong in the above paragraph?

  45. 95
    ChemEng says:

    BPL@92
    Wow… personal attack. Didn’t take long.
    Congrats for missing my point in spectacular fashion.

    Take me literally on the word ‘infinite’ all you want.
    I know you’re smarter than that….. even if you like to equate repeatable controlled experimental results to model outputs. There are well known equations that describe stellar evolution… just like the gas laws! A set of equations for climate? Sorry. Not yet.

    I appreciate what the modellers are trying to do and the difficulty inherent in the task. I truly hope someone or some group can come up with something that isn’t polluted with uncertainty. I just don’t think it wise to hold my breath in the meantime….. and I do have a problem when the models are portrayed as more accurate than they are to support a narrative. Science is suffering… and not just in the field of climate.

    If you write back…. count to 10 first.

  46. 96
    zebra says:

    M Passey and ChemEng,

    There seems to be a flurry of these type of arguments recently– I am not claiming you are all Little Ivans from the GRU with the latest pitch, but…

    This has been answered in multiple forms, directly and metaphorically. How accurate a prediction counts as a prediction? And how possible does a projection have to be in order to be reported?

    What we are doing here is really more engineering than science. You build the structure to withstand a possible earthquake; you have no idea what day, month, year, decade… it might come, if it comes at all.

    So, gosh, is there enough evidence to stop using fossil fuels as soon as possible and create millions of well-paid jobs and stimulate the economy while doing it? (Furrows brow, pouts, puts finger to temple, and strokes chin, in imitation of the current POTUS pretending to “think”. No way it would be as funny as the real thing, of course.)

    If you want to be taken seriously, tell us: What’s your point?

  47. 97
    ChemEng says:

    MP@94…
    Thank you for that…. that is a great post even before you came to my defense.
    I’m not a skeptic per se. I believe that an increase in atmospheric CO2 increases the ‘energy content’ of the climate system ALL OTHER THINGS BEING EQUAL. The problem is that the system, at this point in time, is not understood nearly well enough as a whole for model output to be taken as gospel (and then compared to models we know to be precise). I don’t have an opinion one way or another about the degree to which CO2 warms the planet ON ITS OWN – I just haven’t seen anything conclusive (to me) from either side. Both sides have pushed dubious publications and been disingenuous at times.
    Science isn’t advanced when dissenting views are met with accusations that the dissenter is unable to understand the problem without even properly addressing the argument they’ve presented. Ridiculing the argument (i.e. methyl picrate) is simply a red herring intended to avoid the challenge.
    Just my 2 cents.
    Have a great weekend everyone.

  48. 98
    Mr. Know It All says:

    95 – CE

    One irritating thing about the so-called 97% is that they will not admit even the slightest uncertainty of their “science”. For every question which might cast doubt on AGW, there is always an explanation. This is what we see in religion, right?

    And the other big problem they have is the demonizing of anyone who is skeptical. They’ll call them all kinds of insulting names, etc. Just like the Trump bashers. They just cannot seem to communicate like adults. It’s getting old.

  49. 99
    nigelj says:

    Chemical engineer @95

    “I appreciate what the modellers are trying to do and the difficulty inherent in the task. I truly hope someone or some group can come up with something that isn’t polluted with uncertainty.”

    The climate modelling has proven to be quite good overall, but you will probably never remove all uncertainty from climate models. This is because we cannot put the entire planet in a laboratory and twiddle knobs on CO2 content and solar irradiance etc, etc. Therefore equations on things like climate sensitivity can probably never be proven 100%. This is the hard reality.

    Many climate and geology based issues, and evolution as well, are similar with difficulties replicating things, or gaps in historical data that can never be filled. In comparison industrial chemical processes can be studied in the lab under conditions of near total control.

    But what scientists have done is develop pretty robust models and equations. There is enough historical data and knowledge about how CO2 affects heat energy to be sure things are within a certain range. The models still pretty darn good, enough to say this is the direction we are heading, subject to some error bars. We know this because right now global temperatures are tracking right in the middle of model estimates, and models have predicted many other things pretty well. Prediction is the ultimate substantiation of any theory, and the modelling is certainly scoring some points these days.

    I’m just a lay person interested in this debate, and no climate scientist. But I do read quite widely.

  50. 100
    Ray Ladbury says:

    This thread has really brought out the denialati–from the Aunt Judy “It’s all too hard” pearl clutchers to the full on nutjobs denying the very existence of the greenhouse effect.

    For the former, congratulations. It really takes a lot of work to simply ignore the significant successes made by climate models–and to pretend that even if the models were terrible that would somehow cancel the climate crisis. The reality of the crisis we face doesn’t depend on models of any real sophistication–it’s just that without such models, we are trying to land a plane on a carrier deck in fog without instruments.

    Then there’s the ghg denialist, Mr. Flynn, who is trying to ignore over 200 years of uninterrupted progress in understanding climate. I hate to break this to you, sir, but your failure to understand the science does not constitute a crisis for science. In the time you have spent here, you could have probably found a layman’s explanation of the greenhouse effect that would penetrate even your thick skull.

    That’s the thing about trolls–it’s never about the subject. It’s always about them.