Promoted from the comments, the download of the BBC Radio 4 ‘Now Show’ (Mar 16) is available here (at least for now). Key bit starts at about 18min in, (the rest of the show is pretty funny too).
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307 Responses to "A much more eloquent rebuttal of TGGWS"
Tavitasays
Chuck wrt to Phil,
He admits his mind was made up before coming here (and didn’t even know what the IPCC SPM was), and he admits irrational beliefs concerning the earth “taking care of itself”. (Which is really besides the point; let’s agree the earth takes care of itself, so? since it’s not a sentient being it could care less whether humans suffer or civilization collapses). And what is one to do with someone who prefers the 1 to 9 odds over 9 to 1 odds? And especially if the consequences of being wrong are so dire. But I guess if one thinks that AGW is nuts, then clearly there won’t be any consequences so all those arguments fall on deaf ears. It’s like if you’ve convinced yourself that you are a great driver and will never get into an accident (despite the fact that most people over their life times will) so you don’t by insurance.
And I would like to say that I was impressed by the explanations given concerning the C02 lag issue by the non-experts and if he had wanted more detailed explanations the side bar is there, as well as the literature. The patience and professionalism you all display is amazing. I get no such courtesy on sites that feature anti-AGW threads, I can assure you. (And taking your collective lead, I fully admit I could have dropped the dumb and dumber thing, I’ll try to restrain myself in the future.)
One can only hope that folks with Phil’s mentality are a minority. Fortunately, at least among world governments, his type of thinking doesn’t seem to have much influence and seems to be having less and less as the days go by. I mean really, Inholfe and the rest have basically been reduced to gimmicky personal attacks on Gore and other advocates and, I could be wrong, but I think most rational people realize that alleged hypocrisy doesn’t change the physics of C02 absorption of infrared rays, the outcome of the recent debate notwithstanding.
Hank Robertssays
> Yeah, my SUV don’t make no stinkin’ water vapor …
Chuckle. Someone from a warm climate, who never saw a muffler rusted by driving mostly lots of short trips, might be able to sustain that delusion, but it couldn’t survive passing high school chemistry.
Dave Radosays
Re. 238
Having a background in physics, I am assuming the comparison of uncertainties in Global Warming to General Relativity was a joke
Straw man. The comparison was between the theory of Relativity with the theory of the Greenhouse Effect, which was first discovered by Joseph Fourier in 1824, first demonstrated in laboratory experiments in 1859 by John Tyndall, was first developed into a quantitative theory by the Nobel laureate Svante Arrhenius in 1896, and has since been backed up by literally millions of strands of evidence. It is straightforward physics and is at least as solid as Relativity,.
The uncertainties are about quantification of the effects in a highly complex climate system, not about Greenhouse Effect theory.
PhilCsays
re 253
ok, here’s a final challenge, give me a plausible answer and my main argument will be gone.
A heating ocean gives off co2
co2 causes the planet (and oceans) to heat
the heating ocean gives off more co2 (and water vapour),
causing more heating
and so on
it cannot have happened like this in the past otherwise the planet would have become unihabitable.
So what keeps the ocean temperature and co2 levels in some kind of equillibrium
[[Burning hydrogen emits water. All that extra man-made water vapour will wind up in the atmosphere, and then the CO2 villifiers will finally admit that water vapour is an important greenhouse gas after all! ]]
Water vapor is a stronger greenhouse gas than CO2, yes. But a molecule of water vapor only stays in the atmosphere, on average, for about nine days. A carbon dioxide molecule stays in the atmosphere, on average, for around 200 years. We could double water vapor tomorrow and nearly all the excess would be gone in a month. So this is not a valid objection to a hydrogen economy.
Remember that water cycle we learned about in science class — evaporation, condensation, precipitation. It’s an extremely fast cycle compared to the carbon dioxide cycle.
pete bestsays
Re 255, Ones famous scientists critique of Science was that it marches funeral by funeral to the next discovery. Successful as relativity is (not refuted as yet) it only takes one new experiment to call it into question.
Science is like that. Climate Change unlike relativity is an amalgamation of various scientific inputs from various disciplines and its working relay on a lot of models executed on computers and hence that somehow seems to make it different more pure single discipline approaches. Empirical though it is, climate change is open to more interpretations maybe.
Lynn Vincentnathansays
#245, “Yeah, my SUV don’t make no stinkin’ water vapor you CO2 villifyin’, do goodin’, “flyin’ in the face of economics” science guys/gals.”
Be not afraid to do good.
Did you see the movie, THE JERK? That’s more like our situation. No one knew CO2 (the by-product of our high living standards) would have harmful effects, except maybe Arrhenius and a few others. I didn’t know until the late 1980s. The media were gracious enough then to inform the public, then there was a deep ice age of their silent treatment, so younger persons couldn’t learn about it. One friend even said she had thought GW had been disproved, since she hadn’t seen anything about it on TV or in the news after the early 90s.
So we’ve all nearly been caught, like “the Jerk,” doing things that seemed good and fine, but had a down side.
Now we should look for solutions that can help us throw out the bath water of GHG harm, without throwing out the baby of a good material life. It would be helpful if everyone joined in looking for solutions, and at least implemented those that do not reduce one’s material life and happiness.
Barton makes another good point: the critics don’t have even a basic understanding of 8th grade earth science. With it they would have no argument.
Chuck Boothsays
Re # 254 and Gavin’s comment
Phil,
If you have a degree in physics, you surely know that terrestrial objects (including earth and ocean surfaces) emit longwave infrared radiation in proportion to their Kelvin temperature raised to the 4th power, yes? Some of that will be trapped by atmospheric CO2, but much will escape, thus, as temperature rises, so will emission of terrestrial longwave IR, and the earth’s (and ocean) surface will reach an equilibrium temperature dependent on, among other factors, atmospheric CO2 level.
(If I am mistaken on this point, I trust someone will correct me?)
J.C.Hsays
Lynn,
At the beginning of the 1980s I was the national training director for a carburetor company. It was part of my job to convince auto mechanics and dealership owners to not disable and destroy the anti-pollution equipment on new cars, which was being done. I would put a car on a dyno and disable the catalytic converter. That way I could show the mechanics on an exhaust-gas analyzer how much NOX, CO, and CO2 (these are the three I remember) was produced under varying loads and speeds. We would make horsepower measurements. Then I would re-able the anti-pollution equipment so I could show them that NOX and CO fell to virtual zero even under heavy loads, and that horsepower was not as negatively affected as they had been told.
And then we would point out that CO2, which we described as a harmless gas that plants used, was the only meter on the gas analyzer that still had a significant reading.
I’m certain water vapor is a significant combustion product of gasoline, but I don’t think our exhaust-gas analyzer measured it. I guess we relied on the rain gauge.
Re: My comment #249. The response to #254 and post #260 explain it. Thanks. My math was wrong anyway.
P. Lewissays
Re #238 (PhilC)
I don’t believe that consensus science is science at all.
One often sees such statements from AGW non-believers, and I must say that I find such sentiments odd.
So, PhilC, seeing that you “don’t believe that consensus science is science at all”, what if (hypothetically) the consensus science view was that AGW was nonsense? Is the natural corollary of your position that you’d believe in the non-consensus view, i.e. that you’d then believe in someone who was positing a (non-consensus) link between anthropogenic CO2 emissions and global warming? Surely not! So, with due regard to your stated belief, would you believe in the consensus science view after all in that instance? It would seem you could not, not without sacrificing your belief.
Of course, that is a hypothetical situation that can never arise (since AGW is a reality ;-), though curiously it once was a non-consensus view), and so perhaps it is an unfair question to put (though I think not).
So, what about a less hypothetical example or two. Consider, if you will, the consensus science contributions of the likes of Arrhenius, Avogadro, Bernoulli, Bohr, Boltzmann, Bragg, Brewster, Carnot, Cavendish, Chadwick, Crick, Dalton, Dirac, Einstein, Faraday, Galileo, Gauss, Heisenberg, Hooke, Joule, Kepler, Kelvin, Langmuir, Maxwell, Newton, Ohm, Pauli, Pauling, Planck, Rutherford, Schrodinger, Snell, Thomson, Van’t Hoff, Watson, Zeeman, … (the list is virtually endless)? Are their consensus science contributions not science at all either?
Sounds to me then, if you are correct, that we need some new textbooks, what with all that consensus nonsense out there.
[[I’m certain water vapor is a significant combustion product of gasoline, but I don’t think our exhaust-gas analyzer measured it. I guess we relied on the rain gauge. ]]
Taking gasoline as C8H18 (i.e., pure octane), its combustion is
2 C8H18 + 25 O2 => 16 CO2 + 18 H2O
So yes, water vapor is produced.
tomsays
Wait a second folks. Help me out here.
The climate can be doing only two things- cooling or warming. Nothing else is possible.
For the last 100 year, with the exception of 20 or so, it’s been warming.
Is it your folks’ opinion that the chances are 90% that warming is all attributable to man???
Hank Robertssays
Nothing is “all” attributable to any one thing, Tom.
Who gave you that idea? Seriously, people are misrepresenting the science and when people come in with these mistakes, I want to know if it’s bad journalism, or excellent PR work, that’s getting these ideas into people’s heads so effectively.
[[Is it your folks’ opinion that the chances are 90% that warming is all attributable to man??? ]]
Substitute “most” for “all” and you’d be correct.
Hank Robertssays
Oh, and, Tom, which climate did you mean? The increase in variability isn’t even everywhere, and if you look this up (for example at NOAA’s page, you can find it) you’ll see why that statement is wrong. Who told ya?
David B. Bensonsays
Re #266: tom — I am an amatuer at climatology. My assessment is that all the warming is entirely attributable to man. The reason is that from orbital forcing theory, the climate should be, on average, very gently cooling. But it is not.
At the same time, we know that carbon dioxide is a greenhouse gas. We know that the concentration of carbon dioxide in the air has considerably increased and we know that this is due to bruning fossil fuels. Hence my assessment.
tomsays
Barton.
Ok your interpretaion is that the IPCC is 90% sure that most of the current warming is due to man’s inluence, correct.
Would “Most” mean 51 % or 98% ??
tomsays
Thanks David.
But I guess my question was really about the group’s interpretation of the 90 % confidence as expressed by the IPCC. < If they ever did, I might be wrong about that>
David B. Bensonsays
Re #272: tom — You are welcome and my apologies for the transposition errors.
My personal interpretation of the 90% confidence, “very likely”, is that the IPCC concensus is too conservative. Perhaps it has to do with the manner in which the concensus was formed…
Hank Robertssays
We don’t have the full IPCC statement yet this time ’round, we have the summary for policymakers so far.
Ref:263 & 264
“what if (hypothetically) the consensus science view was that AGW was nonsense? Is the natural corollary of your position that you’d believe in the non-consensus view, i.e. that you’d then believe in someone who was positing a (non-consensus) link between anthropogenic CO2 emissions and global warming? Surely not! So, with due regard to your stated belief, would you believe in the consensus science view after all in that instance? It would seem you could not, not without sacrificing your beliefâ��
You�re assuming I am just being contrary.
Maybe what I should say is that while the consensus is a valid and important part of the scientific process – it proves nothing in itself.
Science is about discovering an accurate way to explain the physical universe. The accuracy of science is measured by how close the predictions are to the real world � the greater the difference the more unclear, or plain wrong the science is.
And the more unclear the science the greater the need for a consensus � Newton does not need a consensus.
I expect we agree that climate is an immensely complex system. At the moment there is a �consensus� theory of how it works and is sufficiently understood to make predictions. Yet, all it would take is for one (as yet) unknown driving factor to be discovered and that current consensus would be proved to have been completely wrong/useless and very damaging.
but as ��.AGW is a reality ,�� you feel sure the chance of any further significant factor being discovered is absolutely zero?
Let me eat some humble pie. I�ve learnt a good deal on this site, some of it has begun to make me think differently about global warming. I also accept that some of my counterarguments do not stand up.
But even accepting that the physical processes of elements within the GW theory are well understood, I still think it is a huge leap to extrapolate these up and arrive at a �Theory of Climate� � one so well understood that a computer model can predict the future.
Computers make a pretty laughable job of predicting the weather beyond a few days – about 18 months ago we were given a long range forecast for a bitterly cold winter which then failed to materialise. So this just confirms my belief that all computer model predictions should be treated with great scepticism â�� sorry, but after 25 years in software modelling thatâ��s my opinion. On which we can disagree.
PhilCsays
and sorry for the strange punctuation characters – it looked ok before I sent it
Blair Dowdensays
Re #276: I wish people would stop talking about consensus. It is really just a lazy appeal to authority rather than making the effort to explain the issues, and also a convenient strawman for denialists. The fact is most climate scientists conclude that human activity has played a large part of the recent global warming. If you have the time, then question that view and find out why it is held.
Climate is chaotic, there are large uncertainties, and there is no single “theory of cliamte”. Climate models are useful investigative tools, and should not be misunderstood as accurate detailed forecasts. Still, it is clear that the climate of the 20th century cannot be explained without anthropogenic contributions, and it is clear that further greenhouse gas emissions will tend to make temperatures rise even further. The may well be other factors that influence the climate, but carbon dioxide accumulates with time, and its contribution to climate will increase, and eventually overwhelm other factors.
A climate model is not a weather model run for a longer time. Climate is an average, and the low frequency variations in climate are much easier to predict than the high frequency variations in weather. For example, the weather forecast may be off by 5 or 10 degrees in a few days, but I can predict the average temperature 6 months from now within a degree or two simply by looking at a climate chart.
Keep asking questions. It is the only way to learn. I still have a lot of questions, which don’t always get answered to my satisfaction right away. My skeptical attitude does not accept statements based on faith or authority, I need to understand why. But with patience, learning does occur.
[[Computers make a pretty laughable job of predicting the weather beyond a few days ]]
Weather is day-to-day variation, and is chaotic (an “initial value problem”). Climate is a long-period (30 years or more) regional or global average (a “boundary values problem”). I don’t know what the temperature will be tomorrow in Kinshasa (weather), but I can be pretty sure it will be hotter than in Stockholm (climate).
Dick Veldkampsays
Re: #276 (PhilC)
It is not correct to compare the weather forecast with a computer simulation of the climate. While the weather is about predicting a particular path in time (of temperature, wind speed, …), in climate one is interested in averages, which are much easier to predict. While it may be difficult to predict the temperature of a particular winter, there is “no” difficulty in forecasting the distribution of temperature for the winters around 2100 (given CO2-concentration at that time); for example that there is a x% probability that the tenperature will be between T1 and T2. Take a look at http://www.bbc.co.uk/sn/climateexperiment/theresult/abouttheresults.shtml to see how this works.
GCMs reproduce climate over the 20th century very well, which gives me a lot of confidence. Even if we grant that GCM are imperfect, should we just ignore their results and trust the uninformed opinion of some contrarian? Better safe than sorry.
PHEsays
Re 278 (Blair Dowden).
Like you: “my skeptical attitude does not accept statements based on faith or authority, I need to understand why”. I also need to understand the evidence and the arguments. I do not, however, agree with another statement of your’s: “it is clear that the climate of the 20th century cannot be explained without anthropogenic contributions, and it is clear that further greenhouse gas emissions will tend to make temperatures rise even further.” However hard I look, what I can see is evidence that these statements could be true, but not that it is ‘clear’ (ie. certain) that they are. In my view, the agreement of many with your statement is based on belief and opinion, rather than a science-based conviction. Many others agree (particularly non scientists) because they accept them as part of a ‘scientific consensus’. However much such statements are repeated as ‘clear’ or ‘certain’, I am not going to believe just because its ‘drummed into me’. The case must be convincing. In my view, it is not (and I am a liberal, environmentally conscientious scientist).
Dansays
re: 281. Yes absolutely, nothing should be “drummed into” anyone. You can easily read the science for yourself. The IPCC report, for example. Which shows that the warming over the past 30 years simply can not be explained by sole consideration of natural forcings or cycles. Only by considering the additional forcing of man-made CO2 is the warming explained. No other process has been presented in the scientific journals by so-called deniers or skeptics which can explain the trend. Thus, they spread “disinformation” about the science. Or worse yet, about the climate scientists themselves. And yet sadly many of those without any credentials in the field of climate science (Crichton, Monckton, etc.) are given soap boxes via the internet or certain media to exclaim that they know something that none of the climate scientists do. That is not science. The science is unequivocably convincing once you read the information available. The consensus is strong throughout the climate science field, as you can also determine. And the scientific debate is quite over, despite the constant cries of those who simply do not understand the science. Or who simply can not admit they are wrong.
Hank Robertssays
PHE — what does “clear” or “certain” mean to you, beyond statistical inference and probability? That’s what’s available in science, you know.
“Clear” would be Religion (or cult, ymmv);
“Proof” would be Mathematics.
David B. Bensonsays
Re #281: PHE — What part of the physics of greenhouse gases iss not both clear and certain? What part about the measured increases in greenhouses gases in the last 50 years is not clear and certain? What part of the known uses of fossil fuels in the last 50 years is not clear and certain? What part about the C14 ratios in the air in the last 50 years is not clear and certain?
PHEsays
Re 282 (DB Benson).
On a general point: The current temperature is not shown to be unprecendented within the past 2000 years. The current temperature trend is not unprecedented in the past 2000 years. On this basis, nothing exceptional or unprecendented is currently occuring. In fact, the current trend (since 1998) is not even upwards.
To answer your questions: (i) CO2 is a minor greenhouse gas. The theory that rising CO2 concentrations could cause a temperature rise is plausible, but so far not demonstrated to be the case. So far, the correlation is no more than circumstantial. (ii)Measurements show an increase in CO2, as well as some other minor greenhouse gases. This is not disputed. What is certain is that there is no correlation between temperature and CO2 rise from 1945 to 1978 and from 1998 to 2006. (iii) We have increased fossil fuel use enormously during the past 50 years – correlating with a substantial improvement in quality of life and life expectancy for most (by no means for all). While coal mining in the past was a very dirty business, this has improved enormously in recent years with cleaner emissions and better safety records. (iv) tell me about C14 ratios. If this supports your point of view, I’m interested to hear. Some readers here will say that many of my comments have already been addressed and rebuffed. But I don’t agree.
I have no ulterior motive other than to defend the integrity of good science. I am all for protecting the environment (eg. discouraging SUVs, recycling, reducing waste and pollution, etc). One hypocrisy I could never support is ‘carbon offsets’ which is simply an excuse for people like Al Gore and Tony Blair to continue polluting as they are, while preaching to the rest of us.
and hoping this information is accurate I see a list containing these views
..the model mean exhibits good agreement with observations.
..The individual models often exhibit worse agreement with observations.
..Many of the non-flux adjusted models suffered from unrealistic climate drift
..All models have shortcomings in their simulations of the present day climate of the stratosphere, which might limit the accuracy of predictions of future climate change.
Etc, etc
I have a couple of questions, and I’m am interested to hear any views on this
if the climate models are less prone to ‘noise’ than weather modeling then why is there such a variance between them – surely this would all be ironed out?
Second question, is that fact that the ‘mean exhibits good agreement with observations’ such a surprise
A good model should be in very good agreement with the real climate so all the modellers start off aiming for the same point, there’s no point desinging a model that will give ‘unrealistic results’
Any models that do give these unacceptable answers would be rejected as wrong leaving only those that are close to the observations with a natural statistical spread around this point.
So if you take all the models that look realistic wont they naturally result in a mean with good agreement with observations but with individual models exhibiting worse agreement with observations.
Zensays
Re #276 (philC): “Newton does not need a consensus”
Yes he does. First off, it is acknowledged that Newton is not infallible: his copuscular theory of light is mostly ignored these days, and Einstein’s general relativity explains phenomena that Netwon’s universal gravitation gets wrong (e.g., Mercury’s orbit). But the main thing is: there’s no big political lobbying effort trying to discredit the use of Newton’s theories, which means that the general public isn’t being bombarded with half-baked “alternative” theories and hence no reason for the scientific consensus view to be explicitly pointed out — the consensus is reasonably approximated by what “everyone knows”.
I have no ulterior motive other than to defend the integrity of good science.
I suggest you read a basic introductory textbook to climate science in that case, as you clearly don’t know even the basics. Or if that’s too much work, try Wikipedia.
Dave
David B. Bensonsays
Re #285: PHE — I suggest you start with
W.F. Ruddiman
Earth’s Climate: Past and Future
W.H. Freeman, 2001.
PHEsays
289, 290. In turn, I suggest the IPCC TAR Scientific Basis (we are still awaiting this for AR4 of course). This is a pretty good review of climate science and of what we know. Just be wary of the ‘Summary for Policymakers’, more accurately described as the ‘Summary by Policymakers’. A key challenge is to find, in the main reports, the scientific backup to the key conclusions stated in the Summary. This then demonstrates how much of the key conclusions are opinion rather than scientifically rigorous conclusions.
Hank Robertssays
>(iv) tell me about C14 ratios
Recreational typing is no fun except for those requesting it.
What have you read in the AIP history about C14 ratios that you don’t find clear and understandable?
Blair Dowdensays
Re #281: The value of a discussion like this is it can reveal sloppy thinking, or at least writing. So I want to amend my statement “it is clear that the climate of the 20th century cannot be explained without anthropogenic contributions“. By “clear” I mean the best available explanation, not certain truth, and it only applies (for me) for the last few decades. While there is is every reason to believe anthropogenic greenhouse gases played a role in the earlier part of the century, it was a much smaller role and they were counterbalanced by other forces (eg. aerosols). Climate modelers claim that the greenhouse signal is required to reproduce that climate, but that argument is beyond my understanding, so I should not be making it.
The last 30 years is different. There is a clear warming trend (that word again, but this time I stand by it), and a convincing explanation for it. We are able to accurately measure all climate inputs for this period, and none of the others can account for the warming.
I am willing to talk more about greenhouse forcings later if you want. No time now.
[[The theory that rising CO2 concentrations could cause a temperature rise is plausible, but so far not demonstrated to be the case. So far, the correlation is no more than circumstantial. ]]
It doesn’t depend on a correlation. It’s basic radiation physics, proved in the lab as early as 1859. CO2 is largely transparent to sunlight but a good absorber of infrared light. Put more of it in the air, and the ground will become warmer if all else is equal.
[[(ii)Measurements show an increase in CO2, as well as some other minor greenhouse gases. This is not disputed. What is certain is that there is no correlation between temperature and CO2 rise from 1945 to 1978 and from 1998 to 2006]]
You can’t pick out the parts that seem to make your case and ignore the rest. You have to use all the available points, and you have to account for all the relevant factors. No one is saying CO2 is related one-to-one with temperature. Things like changes in sunlight distribution, aerosols, albedo and other greenhouse gases also affect temperature. But CO2 is responsible for most of the warming of the past 30 years, which we know from correlating all the data for the past 150 years.
Dave Radosays
RE. 291
Just be wary of the ‘Summary for Policymakers’, more accurately described as the ‘Summary by Policymakers’.
I understand you climate guys getting frustrated about comparisons between weather forecasts and climate models, but I think the comparison is apt.
The climate , like the weather , is subject to interactions which are difficult to identify . TO say the least.the laymen < me> can’t even conceive of a model which could capture the variables that affect climate. Doesn’t mean it can’t happen.
And by the way. The vast majority of weather forecats ARE accurate. The ones that ARENE’t get played up out of proportion.
As our local anchor guy once said: “.. Well Dave, I saw alot of people out there this morning shoveling their partly cloudies out of their driveway”
[[I understand you climate guys getting frustrated about comparisons between weather forecasts and climate models, but I think the comparison is apt.]]
It isn’t. Weather is day-to-day variation and is chaotic. Climate is a long-term average and is deterministic. One is an initial values problem, one is a boundary values problem.
That is one of the reasons I lose sleep over climate change–the only thing that restricts what state the climate goes into is energy–add energy, and it is a certainty that climate becomes less predictable because there are simply more states it can occupy.
Nick Gottssays
Re #297, #298:
According to http://classes.yale.edu/fractals/Chaos/ChaosDef/ChaosDef.html, “chaos”
in the mathematical sense is often referred to as “deterministic
chaos” to distinguish this use from the everyday sense of the word (“a
state of things where chance is supreme”, or “a state of utter
confusion”). The first use in mathematics is given as:
Li, T.-Y., and Yorke, J., “Period three implies chaos,” American
Mathematical Monthly 82 (1975), 985-992.
They prove that if a function f:[0,1] -> [0,1] has a 3-cycle, then f
is chaotic in this sense:
it has periodic points of all periods,
and there is an infinite collection of non-periodic points with
iterates that approach one another arbitrarily closely, only to
move far away again, and that never approach and remain near any
periodic point.
A standard definition now is:
Davaney, R., Introduction to Chaotic Dynamical Systems 2nd Ed,
Addison-Wesley, 1989:
A function f:R -> R exhibits deterministic chaos if it
satisfies three properties:
1) sensitivity to initial conditions arbitrarily close to every
point x, there is a point y with f^n(x) and f^n(y) iterating far apart.
2) dense periodic points arbitrarily close to every point x, there is a
point y with f^m(y) = y for some m.
3) mixing for every pair of intervals I and J, for some k f^k(J)
and I overlap.
So if we’re using “chaos” in the technical sense, it’s not only
compatible with determinism; it requires it. However, it’s not clear
to me how this sense can be applied to a thermodynamically open system like
Earth’s climate (or the entire Earth system of which it is one
aspect).
G. Nicolis and Ilya Prigogine (1977) “Self-Organization in
Non-Equilibrium Systems”, would call the Earth system,
the climate, and coherent weather phenomena such as hurricanes “dissipative
structures”: thermodynamically open systems “feeding off” low entropy
energy sources to maintain their structure, often exhibiting spontaneous
symmetry breaking and in some cases progressive self-organisation over
time. Such systems do also show sensitive dependency to initial
(and/or boundary) conditions, but I think do not necessarily do so. In
particular, their long-term trajectory may be sensitive to some of
the possible small changes in initial or boundary conditions, but not
all. They often have multiple “metastable macrostates”: regions of the
system’s entire statespace which tend to maintain themselves once
established, but not indefinitely; a small external input when the
system is in the interior of such a region will leave it in the same
metastable macrostate, but if it is near the boundary, may shift it
into another – and which one it ends up in may (but need not) depend on precise
details of the external input. As any important system parameter has
its value pushed in one direction by external input, the likely result
is a period of instability, ending when a new metastable macrostate is
entered. If external inputs are pushing a key
parameter in a certain direction, there can be good reasons to believe that
the next metastable macrostate will have certain properties – e.g., if
GHG levels are continually increased, we can expect the period of
instability to be followed by a metastable macrostate with higher mean
temperatures, less latitudinal temperature gradient, less Arctic ice
etc. – but just what that macrostate is like might depend on exact
schedules and mixes of GHG emissions, and many other factors besides.
In summary I’d say neither weather nor climate is strictly chaotic,
both can exhibit sensitive dependence on intial/boundary conditions,
but do so in different ways and (as far as I understand what is currently understood in climate science), at the largest scale the results of dumping lots of GHGs in the atmosphere will be a hotter surface climate.
Bruce G Frykmansays
Re: Water vapor is a stronger greenhouse gas than CO2, yes. But a molecule of water vapor only stays in the atmosphere, on average, for about nine days. A carbon dioxide molecule stays in the atmosphere, on average, for around 200 years.”
Have we got some taggants to attach in order to prove this theory? How long can an angel dance on the head of a pin before he falls off?
Re: “We could double water vapor tomorrow and nearly all the excess would be gone in a month. So this is not a valid objection to a hydrogen economy.”
All we need to do is shut down the world’s economy every other month till things go back into “balance” as a famed climate researcher (Gore) would put it. Everyone just stays in bed for the month fasting – sounds a lot cheaper than windmills.
Chuck wrt to Phil,
He admits his mind was made up before coming here (and didn’t even know what the IPCC SPM was), and he admits irrational beliefs concerning the earth “taking care of itself”. (Which is really besides the point; let’s agree the earth takes care of itself, so? since it’s not a sentient being it could care less whether humans suffer or civilization collapses). And what is one to do with someone who prefers the 1 to 9 odds over 9 to 1 odds? And especially if the consequences of being wrong are so dire. But I guess if one thinks that AGW is nuts, then clearly there won’t be any consequences so all those arguments fall on deaf ears. It’s like if you’ve convinced yourself that you are a great driver and will never get into an accident (despite the fact that most people over their life times will) so you don’t by insurance.
And I would like to say that I was impressed by the explanations given concerning the C02 lag issue by the non-experts and if he had wanted more detailed explanations the side bar is there, as well as the literature. The patience and professionalism you all display is amazing. I get no such courtesy on sites that feature anti-AGW threads, I can assure you. (And taking your collective lead, I fully admit I could have dropped the dumb and dumber thing, I’ll try to restrain myself in the future.)
One can only hope that folks with Phil’s mentality are a minority. Fortunately, at least among world governments, his type of thinking doesn’t seem to have much influence and seems to be having less and less as the days go by. I mean really, Inholfe and the rest have basically been reduced to gimmicky personal attacks on Gore and other advocates and, I could be wrong, but I think most rational people realize that alleged hypocrisy doesn’t change the physics of C02 absorption of infrared rays, the outcome of the recent debate notwithstanding.
> Yeah, my SUV don’t make no stinkin’ water vapor …
Chuckle. Someone from a warm climate, who never saw a muffler rusted by driving mostly lots of short trips, might be able to sustain that delusion, but it couldn’t survive passing high school chemistry.
Re. 238
Straw man. The comparison was between the theory of Relativity with the theory of the Greenhouse Effect, which was first discovered by Joseph Fourier in 1824, first demonstrated in laboratory experiments in 1859 by John Tyndall, was first developed into a quantitative theory by the Nobel laureate Svante Arrhenius in 1896, and has since been backed up by literally millions of strands of evidence. It is straightforward physics and is at least as solid as Relativity,.
The uncertainties are about quantification of the effects in a highly complex climate system, not about Greenhouse Effect theory.
re 253
ok, here’s a final challenge, give me a plausible answer and my main argument will be gone.
A heating ocean gives off co2
co2 causes the planet (and oceans) to heat
the heating ocean gives off more co2 (and water vapour),
causing more heating
and so on
it cannot have happened like this in the past otherwise the planet would have become unihabitable.
So what keeps the ocean temperature and co2 levels in some kind of equillibrium
[Response: Long-wave radiation to space. This is the stabilizing mechanism that everything else works against. Read https://www.realclimate.org/index.php/archives/2006/07/runaway-tipping-points-of-no-return/ to try and understand why runaway effects don’t happen. – gavin]
#253
“Greenhouse Effect….is straightforward physics and is at least as solid as Relativity,”
fair enough, I would agree with you – except you actually wrote
“I think most physicists would only give General Relativity about a 90% probability–maybe less”
[[Burning hydrogen emits water. All that extra man-made water vapour will wind up in the atmosphere, and then the CO2 villifiers will finally admit that water vapour is an important greenhouse gas after all! ]]
Water vapor is a stronger greenhouse gas than CO2, yes. But a molecule of water vapor only stays in the atmosphere, on average, for about nine days. A carbon dioxide molecule stays in the atmosphere, on average, for around 200 years. We could double water vapor tomorrow and nearly all the excess would be gone in a month. So this is not a valid objection to a hydrogen economy.
Remember that water cycle we learned about in science class — evaporation, condensation, precipitation. It’s an extremely fast cycle compared to the carbon dioxide cycle.
Re 255, Ones famous scientists critique of Science was that it marches funeral by funeral to the next discovery. Successful as relativity is (not refuted as yet) it only takes one new experiment to call it into question.
Science is like that. Climate Change unlike relativity is an amalgamation of various scientific inputs from various disciplines and its working relay on a lot of models executed on computers and hence that somehow seems to make it different more pure single discipline approaches. Empirical though it is, climate change is open to more interpretations maybe.
#245, “Yeah, my SUV don’t make no stinkin’ water vapor you CO2 villifyin’, do goodin’, “flyin’ in the face of economics” science guys/gals.”
Be not afraid to do good.
Did you see the movie, THE JERK? That’s more like our situation. No one knew CO2 (the by-product of our high living standards) would have harmful effects, except maybe Arrhenius and a few others. I didn’t know until the late 1980s. The media were gracious enough then to inform the public, then there was a deep ice age of their silent treatment, so younger persons couldn’t learn about it. One friend even said she had thought GW had been disproved, since she hadn’t seen anything about it on TV or in the news after the early 90s.
So we’ve all nearly been caught, like “the Jerk,” doing things that seemed good and fine, but had a down side.
Now we should look for solutions that can help us throw out the bath water of GHG harm, without throwing out the baby of a good material life. It would be helpful if everyone joined in looking for solutions, and at least implemented those that do not reduce one’s material life and happiness.
Barton makes another good point: the critics don’t have even a basic understanding of 8th grade earth science. With it they would have no argument.
Re # 254 and Gavin’s comment
Phil,
If you have a degree in physics, you surely know that terrestrial objects (including earth and ocean surfaces) emit longwave infrared radiation in proportion to their Kelvin temperature raised to the 4th power, yes? Some of that will be trapped by atmospheric CO2, but much will escape, thus, as temperature rises, so will emission of terrestrial longwave IR, and the earth’s (and ocean) surface will reach an equilibrium temperature dependent on, among other factors, atmospheric CO2 level.
(If I am mistaken on this point, I trust someone will correct me?)
Lynn,
At the beginning of the 1980s I was the national training director for a carburetor company. It was part of my job to convince auto mechanics and dealership owners to not disable and destroy the anti-pollution equipment on new cars, which was being done. I would put a car on a dyno and disable the catalytic converter. That way I could show the mechanics on an exhaust-gas analyzer how much NOX, CO, and CO2 (these are the three I remember) was produced under varying loads and speeds. We would make horsepower measurements. Then I would re-able the anti-pollution equipment so I could show them that NOX and CO fell to virtual zero even under heavy loads, and that horsepower was not as negatively affected as they had been told.
And then we would point out that CO2, which we described as a harmless gas that plants used, was the only meter on the gas analyzer that still had a significant reading.
I’m certain water vapor is a significant combustion product of gasoline, but I don’t think our exhaust-gas analyzer measured it. I guess we relied on the rain gauge.
Re: My comment #249. The response to #254 and post #260 explain it. Thanks. My math was wrong anyway.
Re #238 (PhilC)
One often sees such statements from AGW non-believers, and I must say that I find such sentiments odd.
So, PhilC, seeing that you “don’t believe that consensus science is science at all”, what if (hypothetically) the consensus science view was that AGW was nonsense? Is the natural corollary of your position that you’d believe in the non-consensus view, i.e. that you’d then believe in someone who was positing a (non-consensus) link between anthropogenic CO2 emissions and global warming? Surely not! So, with due regard to your stated belief, would you believe in the consensus science view after all in that instance? It would seem you could not, not without sacrificing your belief.
Of course, that is a hypothetical situation that can never arise (since AGW is a reality ;-), though curiously it once was a non-consensus view), and so perhaps it is an unfair question to put (though I think not).
So, what about a less hypothetical example or two. Consider, if you will, the consensus science contributions of the likes of Arrhenius, Avogadro, Bernoulli, Bohr, Boltzmann, Bragg, Brewster, Carnot, Cavendish, Chadwick, Crick, Dalton, Dirac, Einstein, Faraday, Galileo, Gauss, Heisenberg, Hooke, Joule, Kepler, Kelvin, Langmuir, Maxwell, Newton, Ohm, Pauli, Pauling, Planck, Rutherford, Schrodinger, Snell, Thomson, Van’t Hoff, Watson, Zeeman, … (the list is virtually endless)? Are their consensus science contributions not science at all either?
Sounds to me then, if you are correct, that we need some new textbooks, what with all that consensus nonsense out there.
[[I don’t believe that consensus science is science at all.]]
Then you don’t understand modern science, period.
[[I’m certain water vapor is a significant combustion product of gasoline, but I don’t think our exhaust-gas analyzer measured it. I guess we relied on the rain gauge. ]]
Taking gasoline as C8H18 (i.e., pure octane), its combustion is
2 C8H18 + 25 O2 => 16 CO2 + 18 H2O
So yes, water vapor is produced.
Wait a second folks. Help me out here.
The climate can be doing only two things- cooling or warming. Nothing else is possible.
For the last 100 year, with the exception of 20 or so, it’s been warming.
Is it your folks’ opinion that the chances are 90% that warming is all attributable to man???
Nothing is “all” attributable to any one thing, Tom.
Who gave you that idea? Seriously, people are misrepresenting the science and when people come in with these mistakes, I want to know if it’s bad journalism, or excellent PR work, that’s getting these ideas into people’s heads so effectively.
[[Is it your folks’ opinion that the chances are 90% that warming is all attributable to man??? ]]
Substitute “most” for “all” and you’d be correct.
Oh, and, Tom, which climate did you mean? The increase in variability isn’t even everywhere, and if you look this up (for example at NOAA’s page, you can find it) you’ll see why that statement is wrong. Who told ya?
Re #266: tom — I am an amatuer at climatology. My assessment is that all the warming is entirely attributable to man. The reason is that from orbital forcing theory, the climate should be, on average, very gently cooling. But it is not.
At the same time, we know that carbon dioxide is a greenhouse gas. We know that the concentration of carbon dioxide in the air has considerably increased and we know that this is due to bruning fossil fuels. Hence my assessment.
Barton.
Ok your interpretaion is that the IPCC is 90% sure that most of the current warming is due to man’s inluence, correct.
Would “Most” mean 51 % or 98% ??
Thanks David.
But I guess my question was really about the group’s interpretation of the 90 % confidence as expressed by the IPCC. < If they ever did, I might be wrong about that>
Re #272: tom — You are welcome and my apologies for the transposition errors.
My personal interpretation of the 90% confidence, “very likely”, is that the IPCC concensus is too conservative. Perhaps it has to do with the manner in which the concensus was formed…
We don’t have the full IPCC statement yet this time ’round, we have the summary for policymakers so far.
Re. 271 see here.
Ref:263 & 264
“what if (hypothetically) the consensus science view was that AGW was nonsense? Is the natural corollary of your position that you’d believe in the non-consensus view, i.e. that you’d then believe in someone who was positing a (non-consensus) link between anthropogenic CO2 emissions and global warming? Surely not! So, with due regard to your stated belief, would you believe in the consensus science view after all in that instance? It would seem you could not, not without sacrificing your beliefâ��
You�re assuming I am just being contrary.
Maybe what I should say is that while the consensus is a valid and important part of the scientific process – it proves nothing in itself.
Science is about discovering an accurate way to explain the physical universe. The accuracy of science is measured by how close the predictions are to the real world � the greater the difference the more unclear, or plain wrong the science is.
And the more unclear the science the greater the need for a consensus � Newton does not need a consensus.
I expect we agree that climate is an immensely complex system. At the moment there is a �consensus� theory of how it works and is sufficiently understood to make predictions. Yet, all it would take is for one (as yet) unknown driving factor to be discovered and that current consensus would be proved to have been completely wrong/useless and very damaging.
but as ��.AGW is a reality ,�� you feel sure the chance of any further significant factor being discovered is absolutely zero?
Let me eat some humble pie. I�ve learnt a good deal on this site, some of it has begun to make me think differently about global warming. I also accept that some of my counterarguments do not stand up.
But even accepting that the physical processes of elements within the GW theory are well understood, I still think it is a huge leap to extrapolate these up and arrive at a �Theory of Climate� � one so well understood that a computer model can predict the future.
Computers make a pretty laughable job of predicting the weather beyond a few days – about 18 months ago we were given a long range forecast for a bitterly cold winter which then failed to materialise. So this just confirms my belief that all computer model predictions should be treated with great scepticism â�� sorry, but after 25 years in software modelling thatâ��s my opinion. On which we can disagree.
and sorry for the strange punctuation characters – it looked ok before I sent it
Re #276: I wish people would stop talking about consensus. It is really just a lazy appeal to authority rather than making the effort to explain the issues, and also a convenient strawman for denialists. The fact is most climate scientists conclude that human activity has played a large part of the recent global warming. If you have the time, then question that view and find out why it is held.
Climate is chaotic, there are large uncertainties, and there is no single “theory of cliamte”. Climate models are useful investigative tools, and should not be misunderstood as accurate detailed forecasts. Still, it is clear that the climate of the 20th century cannot be explained without anthropogenic contributions, and it is clear that further greenhouse gas emissions will tend to make temperatures rise even further. The may well be other factors that influence the climate, but carbon dioxide accumulates with time, and its contribution to climate will increase, and eventually overwhelm other factors.
A climate model is not a weather model run for a longer time. Climate is an average, and the low frequency variations in climate are much easier to predict than the high frequency variations in weather. For example, the weather forecast may be off by 5 or 10 degrees in a few days, but I can predict the average temperature 6 months from now within a degree or two simply by looking at a climate chart.
Keep asking questions. It is the only way to learn. I still have a lot of questions, which don’t always get answered to my satisfaction right away. My skeptical attitude does not accept statements based on faith or authority, I need to understand why. But with patience, learning does occur.
[[Computers make a pretty laughable job of predicting the weather beyond a few days ]]
Weather is day-to-day variation, and is chaotic (an “initial value problem”). Climate is a long-period (30 years or more) regional or global average (a “boundary values problem”). I don’t know what the temperature will be tomorrow in Kinshasa (weather), but I can be pretty sure it will be hotter than in Stockholm (climate).
Re: #276 (PhilC)
It is not correct to compare the weather forecast with a computer simulation of the climate. While the weather is about predicting a particular path in time (of temperature, wind speed, …), in climate one is interested in averages, which are much easier to predict. While it may be difficult to predict the temperature of a particular winter, there is “no” difficulty in forecasting the distribution of temperature for the winters around 2100 (given CO2-concentration at that time); for example that there is a x% probability that the tenperature will be between T1 and T2. Take a look at http://www.bbc.co.uk/sn/climateexperiment/theresult/abouttheresults.shtml to see how this works.
GCMs reproduce climate over the 20th century very well, which gives me a lot of confidence. Even if we grant that GCM are imperfect, should we just ignore their results and trust the uninformed opinion of some contrarian? Better safe than sorry.
Re 278 (Blair Dowden).
Like you: “my skeptical attitude does not accept statements based on faith or authority, I need to understand why”. I also need to understand the evidence and the arguments. I do not, however, agree with another statement of your’s: “it is clear that the climate of the 20th century cannot be explained without anthropogenic contributions, and it is clear that further greenhouse gas emissions will tend to make temperatures rise even further.” However hard I look, what I can see is evidence that these statements could be true, but not that it is ‘clear’ (ie. certain) that they are. In my view, the agreement of many with your statement is based on belief and opinion, rather than a science-based conviction. Many others agree (particularly non scientists) because they accept them as part of a ‘scientific consensus’. However much such statements are repeated as ‘clear’ or ‘certain’, I am not going to believe just because its ‘drummed into me’. The case must be convincing. In my view, it is not (and I am a liberal, environmentally conscientious scientist).
re: 281. Yes absolutely, nothing should be “drummed into” anyone. You can easily read the science for yourself. The IPCC report, for example. Which shows that the warming over the past 30 years simply can not be explained by sole consideration of natural forcings or cycles. Only by considering the additional forcing of man-made CO2 is the warming explained. No other process has been presented in the scientific journals by so-called deniers or skeptics which can explain the trend. Thus, they spread “disinformation” about the science. Or worse yet, about the climate scientists themselves. And yet sadly many of those without any credentials in the field of climate science (Crichton, Monckton, etc.) are given soap boxes via the internet or certain media to exclaim that they know something that none of the climate scientists do. That is not science. The science is unequivocably convincing once you read the information available. The consensus is strong throughout the climate science field, as you can also determine. And the scientific debate is quite over, despite the constant cries of those who simply do not understand the science. Or who simply can not admit they are wrong.
PHE — what does “clear” or “certain” mean to you, beyond statistical inference and probability? That’s what’s available in science, you know.
“Clear” would be Religion (or cult, ymmv);
“Proof” would be Mathematics.
Re #281: PHE — What part of the physics of greenhouse gases iss not both clear and certain? What part about the measured increases in greenhouses gases in the last 50 years is not clear and certain? What part of the known uses of fossil fuels in the last 50 years is not clear and certain? What part about the C14 ratios in the air in the last 50 years is not clear and certain?
Re 282 (DB Benson).
On a general point: The current temperature is not shown to be unprecendented within the past 2000 years. The current temperature trend is not unprecedented in the past 2000 years. On this basis, nothing exceptional or unprecendented is currently occuring. In fact, the current trend (since 1998) is not even upwards.
To answer your questions: (i) CO2 is a minor greenhouse gas. The theory that rising CO2 concentrations could cause a temperature rise is plausible, but so far not demonstrated to be the case. So far, the correlation is no more than circumstantial. (ii)Measurements show an increase in CO2, as well as some other minor greenhouse gases. This is not disputed. What is certain is that there is no correlation between temperature and CO2 rise from 1945 to 1978 and from 1998 to 2006. (iii) We have increased fossil fuel use enormously during the past 50 years – correlating with a substantial improvement in quality of life and life expectancy for most (by no means for all). While coal mining in the past was a very dirty business, this has improved enormously in recent years with cleaner emissions and better safety records. (iv) tell me about C14 ratios. If this supports your point of view, I’m interested to hear. Some readers here will say that many of my comments have already been addressed and rebuffed. But I don’t agree.
I have no ulterior motive other than to defend the integrity of good science. I am all for protecting the environment (eg. discouraging SUVs, recycling, reducing waste and pollution, etc). One hypocrisy I could never support is ‘carbon offsets’ which is simply an excuse for people like Al Gore and Tony Blair to continue polluting as they are, while preaching to the rest of us.
ref 280
having read WIKIPEDIA page on climate models
and hoping this information is accurate I see a list containing these views
..the model mean exhibits good agreement with observations.
..The individual models often exhibit worse agreement with observations.
..Many of the non-flux adjusted models suffered from unrealistic climate drift
..All models have shortcomings in their simulations of the present day climate of the stratosphere, which might limit the accuracy of predictions of future climate change.
Etc, etc
I have a couple of questions, and I’m am interested to hear any views on this
if the climate models are less prone to ‘noise’ than weather modeling then why is there such a variance between them – surely this would all be ironed out?
Second question, is that fact that the ‘mean exhibits good agreement with observations’ such a surprise
A good model should be in very good agreement with the real climate so all the modellers start off aiming for the same point, there’s no point desinging a model that will give ‘unrealistic results’
Any models that do give these unacceptable answers would be rejected as wrong leaving only those that are close to the observations with a natural statistical spread around this point.
So if you take all the models that look realistic wont they naturally result in a mean with good agreement with observations but with individual models exhibiting worse agreement with observations.
Re #276 (philC): “Newton does not need a consensus”
Yes he does. First off, it is acknowledged that Newton is not infallible: his copuscular theory of light is mostly ignored these days, and Einstein’s general relativity explains phenomena that Netwon’s universal gravitation gets wrong (e.g., Mercury’s orbit). But the main thing is: there’s no big political lobbying effort trying to discredit the use of Newton’s theories, which means that the general public isn’t being bombarded with half-baked “alternative” theories and hence no reason for the scientific consensus view to be explicitly pointed out — the consensus is reasonably approximated by what “everyone knows”.
Another rebuttal of TGGWS:
http://adaisythroughconcrete.blogspot.com/2007/03/ok-now-im-cross.html
Re. 285
I suggest you read a basic introductory textbook to climate science in that case, as you clearly don’t know even the basics. Or if that’s too much work, try Wikipedia.
Dave
Re #285: PHE — I suggest you start with
W.F. Ruddiman
Earth’s Climate: Past and Future
W.H. Freeman, 2001.
289, 290. In turn, I suggest the IPCC TAR Scientific Basis (we are still awaiting this for AR4 of course). This is a pretty good review of climate science and of what we know. Just be wary of the ‘Summary for Policymakers’, more accurately described as the ‘Summary by Policymakers’. A key challenge is to find, in the main reports, the scientific backup to the key conclusions stated in the Summary. This then demonstrates how much of the key conclusions are opinion rather than scientifically rigorous conclusions.
>(iv) tell me about C14 ratios
Recreational typing is no fun except for those requesting it.
What have you read in the AIP history about C14 ratios that you don’t find clear and understandable?
Re #281: The value of a discussion like this is it can reveal sloppy thinking, or at least writing. So I want to amend my statement “it is clear that the climate of the 20th century cannot be explained without anthropogenic contributions“. By “clear” I mean the best available explanation, not certain truth, and it only applies (for me) for the last few decades. While there is is every reason to believe anthropogenic greenhouse gases played a role in the earlier part of the century, it was a much smaller role and they were counterbalanced by other forces (eg. aerosols). Climate modelers claim that the greenhouse signal is required to reproduce that climate, but that argument is beyond my understanding, so I should not be making it.
The last 30 years is different. There is a clear warming trend (that word again, but this time I stand by it), and a convincing explanation for it. We are able to accurately measure all climate inputs for this period, and none of the others can account for the warming.
I am willing to talk more about greenhouse forcings later if you want. No time now.
[[The theory that rising CO2 concentrations could cause a temperature rise is plausible, but so far not demonstrated to be the case. So far, the correlation is no more than circumstantial. ]]
It doesn’t depend on a correlation. It’s basic radiation physics, proved in the lab as early as 1859. CO2 is largely transparent to sunlight but a good absorber of infrared light. Put more of it in the air, and the ground will become warmer if all else is equal.
[[(ii)Measurements show an increase in CO2, as well as some other minor greenhouse gases. This is not disputed. What is certain is that there is no correlation between temperature and CO2 rise from 1945 to 1978 and from 1998 to 2006]]
You can’t pick out the parts that seem to make your case and ignore the rest. You have to use all the available points, and you have to account for all the relevant factors. No one is saying CO2 is related one-to-one with temperature. Things like changes in sunlight distribution, aerosols, albedo and other greenhouse gases also affect temperature. But CO2 is responsible for most of the warming of the past 30 years, which we know from correlating all the data for the past 150 years.
RE. 291
You’ve got that wrong as well – see here.
I understand you climate guys getting frustrated about comparisons between weather forecasts and climate models, but I think the comparison is apt.
The climate , like the weather , is subject to interactions which are difficult to identify . TO say the least.the laymen < me> can’t even conceive of a model which could capture the variables that affect climate. Doesn’t mean it can’t happen.
And by the way. The vast majority of weather forecats ARE accurate. The ones that ARENE’t get played up out of proportion.
As our local anchor guy once said: “.. Well Dave, I saw alot of people out there this morning shoveling their partly cloudies out of their driveway”
[[I understand you climate guys getting frustrated about comparisons between weather forecasts and climate models, but I think the comparison is apt.]]
It isn’t. Weather is day-to-day variation and is chaotic. Climate is a long-term average and is deterministic. One is an initial values problem, one is a boundary values problem.
Barton, Climate is not deterministic. At some level, climate is probably chaotic as well, in the sense that if you perturb it, you cannot predict with certainty what state it will wind up in. With climate, it is just that you are looking at long-term averages. See:
http://www.giss.nasa.gov/research/briefs/hansen_03/
and
http://www.grida.no/climate/ipcc_tar/wg1/045.htm
That is one of the reasons I lose sleep over climate change–the only thing that restricts what state the climate goes into is energy–add energy, and it is a certainty that climate becomes less predictable because there are simply more states it can occupy.
Re #297, #298:
According to
http://classes.yale.edu/fractals/Chaos/ChaosDef/ChaosDef.html, “chaos”
in the mathematical sense is often referred to as “deterministic
chaos” to distinguish this use from the everyday sense of the word (“a
state of things where chance is supreme”, or “a state of utter
confusion”). The first use in mathematics is given as:
Li, T.-Y., and Yorke, J., “Period three implies chaos,” American
Mathematical Monthly 82 (1975), 985-992.
They prove that if a function f:[0,1] -> [0,1] has a 3-cycle, then f
is chaotic in this sense:
it has periodic points of all periods,
and there is an infinite collection of non-periodic points with
iterates that approach one another arbitrarily closely, only to
move far away again, and that never approach and remain near any
periodic point.
A standard definition now is:
Davaney, R., Introduction to Chaotic Dynamical Systems 2nd Ed,
Addison-Wesley, 1989:
A function f:R -> R exhibits deterministic chaos if it
satisfies three properties:
1) sensitivity to initial conditions arbitrarily close to every
point x, there is a point y with f^n(x) and f^n(y) iterating far apart.
2) dense periodic points arbitrarily close to every point x, there is a
point y with f^m(y) = y for some m.
3) mixing for every pair of intervals I and J, for some k f^k(J)
and I overlap.
So if we’re using “chaos” in the technical sense, it’s not only
compatible with determinism; it requires it. However, it’s not clear
to me how this sense can be applied to a thermodynamically open system like
Earth’s climate (or the entire Earth system of which it is one
aspect).
G. Nicolis and Ilya Prigogine (1977) “Self-Organization in
Non-Equilibrium Systems”, would call the Earth system,
the climate, and coherent weather phenomena such as hurricanes “dissipative
structures”: thermodynamically open systems “feeding off” low entropy
energy sources to maintain their structure, often exhibiting spontaneous
symmetry breaking and in some cases progressive self-organisation over
time. Such systems do also show sensitive dependency to initial
(and/or boundary) conditions, but I think do not necessarily do so. In
particular, their long-term trajectory may be sensitive to some of
the possible small changes in initial or boundary conditions, but not
all. They often have multiple “metastable macrostates”: regions of the
system’s entire statespace which tend to maintain themselves once
established, but not indefinitely; a small external input when the
system is in the interior of such a region will leave it in the same
metastable macrostate, but if it is near the boundary, may shift it
into another – and which one it ends up in may (but need not) depend on precise
details of the external input. As any important system parameter has
its value pushed in one direction by external input, the likely result
is a period of instability, ending when a new metastable macrostate is
entered. If external inputs are pushing a key
parameter in a certain direction, there can be good reasons to believe that
the next metastable macrostate will have certain properties – e.g., if
GHG levels are continually increased, we can expect the period of
instability to be followed by a metastable macrostate with higher mean
temperatures, less latitudinal temperature gradient, less Arctic ice
etc. – but just what that macrostate is like might depend on exact
schedules and mixes of GHG emissions, and many other factors besides.
In summary I’d say neither weather nor climate is strictly chaotic,
both can exhibit sensitive dependence on intial/boundary conditions,
but do so in different ways and (as far as I understand what is currently understood in climate science), at the largest scale the results of dumping lots of GHGs in the atmosphere will be a hotter surface climate.
Re: Water vapor is a stronger greenhouse gas than CO2, yes. But a molecule of water vapor only stays in the atmosphere, on average, for about nine days. A carbon dioxide molecule stays in the atmosphere, on average, for around 200 years.”
Have we got some taggants to attach in order to prove this theory? How long can an angel dance on the head of a pin before he falls off?
Re: “We could double water vapor tomorrow and nearly all the excess would be gone in a month. So this is not a valid objection to a hydrogen economy.”
All we need to do is shut down the world’s economy every other month till things go back into “balance” as a famed climate researcher (Gore) would put it. Everyone just stays in bed for the month fasting – sounds a lot cheaper than windmills.