by Kesten C. Green, J. Scott Armstrong, and Willie Soon
The human race has prospered by relying on forecasts that the seasons will follow their usual course, while knowing they will sometimes be better or worse. Are things different now?
For the fifth time now, the Intergovernmental Panel on Climate Change claims they are. The difference, the IPCC asserts, is increased human emissions of carbon dioxide: a colorless, odorless, non-toxic gas that is a byproduct of growing prosperity. It is also a product of all animal respiration and is also essential for most life on Earth, yet in total it makes up only 0.0004 of the atmosphere.
The IPCC assumes that the relatively small human contribution of this gas to the atmosphere will cause global warming, and insist that the warming will be dangerous.
Other scientists contest the IPCC assumptions, on the grounds that the climatological effect of increases in atmospheric carbon dioxide is trivial—and that the climate is so complex and insufficiently understood that the net effect of human emissions on global temperatures cannot be forecasted.
The computer models that the authors of the IPCC reports rely on are complicated representations of the assumption that human carbon dioxide emissions are now the primary factor driving climate change and will substantially overheat the Earth. The models include many assumptions that mainstream scientists question.
The modelers have correctly stated that they produce scenarios, not forecasts. Scenarios are stories constructed from a collection of assumptions. Well-constructed scenarios can be very convincing, in the same way that a well-crafted book or film can be.
The IPCC and its supporters promote these scary scenarios as if they were forecasts. However, scenarios are neither forecasts nor the product of a validated forecasting method.
The IPCC modelers were apparently unaware of decades of forecasting research. Our audit of the procedures used to create their apocalyptic scenarios found that they violated 72 of 89 relevant scientific forecasting principles. Would you go ahead with your flight if you overheard two of the ground crew discussing how the pilot had skipped 80 percent of the pre-flight safety checklist?
Thirty-nine forecasting experts from many disciplines from around the world developed the forecasting principles from published experimental research. A further 123 forecasting experts reviewed the work. The principles were published in 2001 and they are freely available on the Internet to help forecasters produce the best forecasts they can and to help forecast users determine the validity of forecasts. These principles are the only published set of evidence-based standards for forecasting.
Global warming alarmists nevertheless claim that the “nearly all” climate scientists believe dangerous global warming will occur. This is a strange claim, in view of the fact more than 30,000 American scientists signed the Oregon Petition, stating that there is no basis for dangerous manmade global warming forecasts, and “no convincing evidence” that carbon dioxide is dangerously warming the planet or disrupting its climate.
Most importantly, computer models and scenarios are not evidence—and validation does not consist of adding up votes. Such an approach can only be detrimental to the advancement of scientific knowledge. Validation requires comparing predictions to actual observations, and the IPCC models have failed in that regard.
Given the expensive policies proposed and implemented in the name of preventing dangerous manmade global warming, we are astonished that there is only one published peer-reviewed paper that claims to provide scientific forecasts of long-range global mean temperatures. The paper is our own 2009 article in the International Journal of Forecasting.
Our paper examined the state of knowledge and available empirical (that is, actually measured) data, in order to select appropriate evidence-based procedures for long-range forecasting of global mean temperatures. Given the complexity and uncertainty of the situation, we concluded that the “no-trend” model is the proper method to use. The conclusion is based on a substantial body of research that found complex models do not work well in complex and uncertain situations. This finding might be puzzling to people who are unfamiliar with the research on forecasting.
We tested the no-trend model, using the same data that the IPCC uses. To do this, we produced annual forecasts from one to 100 years ahead, starting from 1851 and stepping forward year-by-year until 1975, the year before the current warming alarm was raised. (This is also the year when Newsweek and other magazines reported that scientists were “almost unanimous” that Earth faced a new period of global cooling.) We conducted the same analysis for the IPCC scenario of temperatures increasing at a rate of 0.03 degrees Celsius (0.05 degrees Fahrenheit) per year in response to increasing human carbon dioxide emissions.
This procedure yielded 7,550 forecasts for each method. The findings?
Overall, the no-trend forecast error was one-seventh the error of the IPCC scenario’s projection. They were as accurate as or more accurate than the IPCC temperatures for all forecast horizons. Most important, the relative accuracy of the no-trend forecasts increased for longer horizons. For example, the no-trend forecast error was one-twelfth that of the IPCC temperature scenarios for forecasts 91 to 100 years ahead.
Our research in progress scrutinizes more forecasting methods, uses more and better data, and extends our validation tests. The findings strengthen the conclusion that there are no scientific forecasts that predict dangerous global warming.
Is it surprising that the government would support an alarm lacking scientific support? Not really. In our study of situations that are analogous to the current alarm over scenarios of global warming, we identified 26 earlier movements based on scenarios of manmade disaster, including the global cooling alarm in the 1960s to 1970s. None of them were based on scientific forecasts. And yet, governments imposed costly policies in response to 23 of them. In no case did the forecast of major harm come true.
There is no support from scientific forecasting for an upward trend in temperatures, or a downward trend. Without support from scientific forecasts, the global warming alarm is baseless and should be ignored.
Government programs, subsidies, taxes and regulations proposed as responses to the global warming alarm result in misallocations of valuable resources. They lead to inflated energy prices, declining international competitiveness, disappearing industries and jobs, and threats to health and welfare.
Humanity can do better with the old, simple, tried-and-true no-trend climate forecasting model. This traditional method is also consistent with scientific forecasting principles.
_____________
Dr. Kesten C. Green is with the University of South Australia in Adelaide and is director of the major website on forecasting methods, forecastingprinciples.com, and has published twelve peer-reviewed articles on forecasting.Professor J. Scott Armstrong teaches at the University of Pennsylvania in Philadelphia and is a founder of the two major journals on forecasting methods, editor of the Principles of Forecasting handbook, and the world’s most highly cited author on forecasting methods. Dr. Willie Soon of Salem, MA for the past 20 years has published extensively on solar and other factors that cause climate changes. Copies of the authors’ climate forecasting papers are available at www.PublicPolicyForecasting.com.
I think you’re missing the point, or perhaps we’ve not made it clear. I think it reasonable to say that the majority of comments on this blog come from people that are very concerned about the environment and science. I know I feel that the global warming scare shakes the foundations of scientific integrity. Since this is being done in the name of environmentalism, it removes a foundation from that concern as well. If this scare continues, the science and environmental advocacy we support could be irreparably damaged.
See – owe to Rich says:
October 16, 2013 at 12:33 am
(And Scafetta’s model of two cycles plus quadratic does even better than that, but probably would not if matched to 1800-1850 temperatures.)
*************************
The model that you are referring to is quite obsolete. You need to look at the upgraded harmonic models that I have recently proposed. The quadratic trend is not used any more and additional cycles are added.
For example, look at
Scafetta, N. 2013. Discussion on climate oscillations: CMIP5 general circulation models versus a semi-empirical harmonic model based on astronomical cycles. Earth-Science Reviews 126, 321-357.
http://www.sciencedirect.com/science/article/pii/S0012825213001402
see Figure 24, and Figures 25-27
see also:
Scafetta N., 2013. Solar and planetary oscillation control on climate change: hind-cast, forecast and a comparison with the CMIP5 GCMs. Energy & Environment 24(3-4), 455–496.
http://multi-science.metapress.com/content/p7n531161076t3p6/?p=c84512f97a5845ec995057c3818fb1d2&pi=0
In any case to “forecasts” or better to provide reliable projections one need to well understand the natural dynamics of the climate system and also of the solar activity. This has been provided in my papers.
see my web-site
http://people.duke.edu/~ns2002/#astronomical_model
http://people.duke.edu/~ns2002/#astronomical_model_1
Steven Mosher: Quote:‘ on the grounds that the climatological effect of increases in atmospheric carbon dioxide is trivial—and that the climate is so complex and insufficiently understood that the net effect of human emissions on global temperatures cannot be forecasted.”
Response The climate is too complex. we conclude the effect of C02 is trivial.
You missed the key clause in the quote: the climatological effect of increases in atmospheric carbon dioxide is trivial. They might be wrong, but you should focus on the key claim, imho.
An expert in forecasting can most definitely forecast the climate without being an IPCC level scientist, per some doubts above. They would need to borrow the general frameworks and assumptions from the scientists (their expertise) but then put them in more robust forecasting frameworks and analyze them using sensitivity analysis on those same assumptions, among other things. To my knowledge that is what they have done – they do not need to be climate scientists to analyze the forecasting accuracy of different models as long as they include all the same elements.
ed on It is like predicting the future path of a ball sitting on top of a tall building after you kick it off the building using the fact that it has sat stationary on top of the building up to that time…Therefore, your prediction would be that the height wouldn’t change with time.
No, it is nothing at all like this. It is like asserting that a nonlinear system that is following a poincare cycle in some ten or twenty dimensions that has a clearly evident and easily computable four parameter secular trend (as Mr. Scafetta is happy to point out although it is equally evident just from looking at the data itself) had one set of (non-computable) causes for the variation in the first half of the data and an entirely different set of (equally non-computable) causes for the variation in the second half of the data and it is just pure chance that they happen to be fit by the same form where the GCMs themselves are not well fit in EITHER half of the data and do not even agree well with each other.
You cannot reduce this to a one-dimensional linearizable problem because it isn’t one.
As for Park, I missed the one line about his surface physics papers, perhaps because none of the papers linked in the references section of the article were in this category. But you still miss the point. a) Park hasn’t done any climate science research that I can see (and now I’m working straight from his CV). Indeed, he hasn’t published a paper in physics per se since 1988, and while chemisorption and thin films and surface physics are indeed interesting — I did some work on this myself STARTING at around this same time — he seems to have transitioned away from doing actual physics research and into physics policy in the mid-80’s. b) Even if he had done some climate physics, that would not mean that his conclusions regarding CAGW are correct, any more than the fact that he hasn’t means his conclusions are incorrect. c) Dr. Soon, in fact, has done and published climate research. He has a physics Ph.D. He AFAIK is employed by Harvard, which is not exactly the easiest institution in the world to get tenure in.
If you want to play the “Argument by authority” card, you are playing Dr. Park’s expertise in detecting supposedly badly done science in a field he has never worked in against Dr. Soon’s expertise in his primary field while employed at one of the most prestigious institutions in the academic world. You don’t “lose” this argument, of course, because the entire argument is fallacious, an excuse to dismiss a piece of work without examining it, but you hardly “win” it either. Note well that I’m not addressing whether or not the work itself is correct or incorrect — I’m even aware of the Bayesian reasoning one might use to reject crank science based on the (lack of) credentials of the arguer — we do this sort of thing all the time, but seriously, are you attacking Soon’s credentials?
So please understand — I wasn’t attempting to attack Park’s competence in physics. I was pointing out the logical fallacy of presenting his remarks on Soon as some sort of “expert opinion” that we could rely on to dismiss the work that is the subject of the top article without even bothering to read it. I’d do the same thing if YOU made those remarks, or if Michael Mann or anyone else who WORKS in climate science made those remarks. They are irrelevant to the issue at hand and frankly inappropriate in science, however commonly they are made in the ultimately NON-scientific debate surrounding “climate science”. A logical fallacy is a logical fallacy. I have no idea whether or not Soon is right, wrong, or in between. I have no reason, however, to think that Soon is incompetent in climate science a priori; if anything I have good reasons to think that he is NOT incompetent. Which doesn’t make him right, wrong, or in between, but it guarantees that I’ll look at what he writes now to decide, not what Dr. Park said about something else that Soon wrote long ago.
So, let’s look at some numerology:
http://www.woodfortrees.org/plot/hadcrut4gl/from:1800/to:2013/plot/hadcrut4gl/trend
It is a simple fact that a purely linear trend from 1840-whatever to the present explains almost all of the observed climate variation from that time to the present. It is also a simple fact that almost all of the rest of the climate variation can be explained with an additional sinusoid with amplitude around 0.2 C and period somewhere in the ballpark of 50 to 70 years. Since we are fitting an anomaly, one degree of freedom doesn’t count and this is a three parameter fit that would explain the data essentially perfectly if subjected to any reasonable statistical test.
I cannot meaningfully plot CO_2 on wft, because it will not let me choose the axes and doesn’t include even estimates of CO_2 pre-Mauna-Loa, so the range of the data is entirely different. I cannot really plot the temperature on wft, because we do not know what to add to the “anomaly” to make an absolute temperature, but if we did add 288 K as a not unreasonable guesstimate, we’d end up with a straight flat line with one-pixel noise barely visible on it across all 160-170 years in the case of GAST, while CO_2 would increase by roughly 1/3, almost all of that increase occuring since 1950. Comparing the two graphs, nobody sane could possibly nod their head wisely and say of course the CO_2 graph explains the GAST graph.
Nor could they say that it explains the anomaly (GASTA) graph, given that the increases and decreases in global temperature can so readily be explained as a linear trend plus a zero-sum oscillation that doesn’t treat the interval post 1950 any differently than it treats the interval from 1890 to 1950, when the increase in GAST/GASTA was almost identical to that from 1950 to 2013 — so much so that if one presents the curves side by side and asks someone to identify which one came from the CO_2 era it is a bit tricky to do so!
It isn’t as simple as “gravity turned on” in 1950 in the form of CO_2, so all of the increase post 1950 MUST be due to CO_2. CO_2 turned on, but many other things changed as well. Soots. Aerosols. The state of the sun. Albedo. Land use. And we cannot explain the variation from the FIRST half of the GASTA curve, the pre-CO_2 part. We can hypothesize POSSIBLE explanations, sure, but we literally lack the data to be at all certain that any particular hypothesis is correct.
So here’s the simplest null hypothesis one can imagine. Forget physical models entirely. Is there any reason to think, from the GASTA data alone, that anything changed from the pre-1950 part of the curve to the post 1950 part of the curve. Try to forget that this is supposed to be GASTA (an anomaly). Try to forget that it is temperature vs time. Pretend that it is an electrical signal with a great deal of noise and you have no idea what the source of the signal is. Do you look at this curve and go “Wow, things really changed in 1950, didn’t they” or do you go “Wow, this curve really looks like a linear trend plus a superimposed sinusoid and nothing changes relative to this assumption to any extent I’d expect to be statistically resolvable across the entire range of data.”
Now let’s apply the right metaphor, which isn’t a static building. Suppose the woodsfortrees data above described the height of a 288 inch tree as an “anomaly” above the ground, and we’ve renormalized so that a year is now 60 years. The noise visible in the graph is the noise in our daily measurements as the top of the tree blows around in the wind. Somebody has asserted that they’ve invented a fertilizer that is guaranteed to double the rate of growth of trees, but you doubt it. Sure, it contains a lot of nitrogen, and nitrogen can definitely make things grow faster in the lab, but it can also burn the roots, or be out of balance with phosphorous and not have much of an effect or it can even have a NEGATIVE effect, killing the tree. You would love to buy the fertilizer if it works, but it is very, very expensive.
The people selling you the fertilizer present you the data above. They started adding the fertilizer around the “week” corresponding to 1950, which just happened to be mid-November. Unsurprisingly, there wasn’t much growth. They threw on more and more fertilizer in December, January, March — every month they added even more fertilizer than they had the month before, and sure enough, in March the tree started to grow quickly! It grew while they added more and more and more fertilizer, all the way up to (wait for it) September, where the growth suddenly stopped as fall summer came to an end.
The fertilizer company now offers to sell you a huge mountain of this fertilizer for a trillion dollars (I said it was expensive). They point out how as they added more and more fertilizer during March, the tree went from nearly dormant to simply bursting with growth. They’re not certain why the tree STOPPED growing in August and actually got a bit shorter as September rolled around, but they are confident that this fertilizer will make that damn tree grow all year around, at twice the rate it has ever grown before!
Do you seriously think that the data from just the two “years” present is at all supportive of such a claim? I don’t. The overall growth in year one is identical to the growth in year two, within a few leaves and a good wind. In both cases there is an average growth rate (the same growth rate) modulated by a seasonal variation. If we didn’t know about the seasons, we would INVENT them looking at this graph. We would NEVER assume that the graph itself is good evidence for the fertilizer doubling the rate of tree growth starting in 1950, and would write off any such claim with a trillion dollar pricetag as somebody wanting to get very, very rich at the expense of somebody very, very gullible. Even if the fertilizer contains nitrogen, even if nitrogen is a well-known tree nutrient, it may well be the case that there are many things that limit or affect the growth rate of the tree, and merely boosting nitrogen alone — however well it might work on paper — might not work in practice.
When the people who are trying to sell you the fertilizer try to argue that they have solid proof that the tree was really about to get shorter, that insects were attacking the roots and there was a drought and the winter was colder than usual so that their fertilizer really was entirely responsible for the second visible “season” of growth but not the first, well, if you buy that I’ve got a bridge for sale that you might want to take a look at, it could be a really good investment for you.
With that said, sure, the fertilizer COULD be great, they could be right that insects were in the roots etc. But there is no hurry — with a trillion dollar price tag it seems pretty reasonable to wait another year, or even two, and try to get a lot more, a lot better, data before betting the very lives, wealth and happiness of all the people on the planet all on the fact that nitrogen is definitely a plant nutrient and might have contributed some fraction to the total growth observed in a slowly, steadily growing tree.
The only weakness in this metaphor is the same weakness as your metaphor of the building. We do not know how to predict the growth rate of the tree. We don’t even know how tall the tree, or building really is. We don’t know if they are sitting on ground that is settling, or being thrust up, due to causes we haven’t figured out yet. We don’t know about the life cycle of the tree, whether the growth rate itself varies in some secular fashion over time. We simply haven’t been studying trees, or even buildings, long enough. We are only two years old as far as trees are concerned — we can’t even properly explain the seasons yet because we haven’t observed enough of them. We are similarly clueless about the effects of moles, drought or rainfall, hot versus cold summers or winters, insects and diseases, availability of other core nutrients, and whether or not the tree is in competition with other nearby growth. We can see that those things should have some effect, but we’ve only really had good instruments to look into those competing and interlocked effects for much less than a year, where we can hypothesize that a cold winter might hurt the tree’s roots but help by killing off tree parasites and could be associated with a wet snowy winter or a dry bitter winter equally easily that further confounds the effects of “cold”.
I have to say, I just get tired of people trivializing the problem. It is a damn sight easier to figure out the effect of fertilizer on trees — theoretically or experimentally — than it is to understand the climate and its probable response to a linear perturbation of some sort or another. Yet things nobody would accept in the context of trees, not without extensive, double blind experimental evidence to support it, people are happy to accept in a heartbeat in climate science, where things are if anything MUCH MORE COMPLEX.
rgb
Great post, rgb.
Unfortunately, facts and logic do not sway believers in CAGW by CO2.
Doesn’t appear that facts and logic sway certain politicians, either.
🙁
JohnWho:
I agree with you that Robert Brown made a “great post” in this thread as a response to Joel Shore. He often makes great posts and a post he made on another WUWT thread earlier today is among the best things ever put on WUWT.
However, and with respect, I suggest that it would be good for us all to stand back from commenting, get in the popcorn, and wait.
As we know from long experience, Joel Shore makes posts which cannot withstand logical scrutiny, he receives a rebuttal, and then he drags the supplier of the rebuttal into the ‘weird and wacky world’ of Joel Shore. And that world is like a lobster pot: falling in is easy but finding a way out is hard.
If anyone can tear through the wall of the lobster pot then Robert Brown is likely to be the one with that ability. So, we need to stand back and await the show – not get involved in it – because it should be fun.
Richard
@richard S. Courtney –
I am never one to turn down popcorn when freely offered, so I accept your suggestion with popcorn seasoning in hand.
Perhaps a riddle while we wait?
What is the difference between the Jersey Shore and Joel Shore?
Answer: One is a mass of silicon being overwhelmed by a huge ocean and
the other is, uh, …
OK, so there is no difference.
I’ve never been good at riddles anyway.
🙂
Robert Brown:
You’re missing the forest through the trees here.
As per the Oregon petition, the basic facts, as Park well-described it are these:
(1) The paper and petition were mailed en-mass to members of various scientific departments at universities (and perhaps other places) and only YES votes, i.e., people who chose to sign the petition were counted.
(2) The paper was formatted in a way and Seitz noted his position as a past President of the National Academy of Sciences in a way that was sufficiently deceptive that NAS felt compelled to issue a statement that said that the paper had not and was not even being considered to appear in their proceedings and that the claims in the paper were in contradiction to the Academies own conclusions. You can see their full statement here: http://www8.nationalacademies.org/onpinews/newsitem.aspx?RecordID=s04201998
As for climate, even if everything that you said was true, why did Armstrong and Green not just come right out and say that the rate of increase predicted by the IPCC over the next century is quite a bit higher than the average rate of increase over the last 160 years? Why did they have to hide this behind a bunch of mumbo-jumbo? The answer is probably because they were creating a straw man to destroy but they didn’t want to make it quite so obvious what their straw man was!
And, what you say has a lot of additional problems. Yes, climate is complicated, but that doesn’t mean that nothing can be determined about it. We are able to very clearly see and predict the local seasonal effects due to changes in forcing, despite all this complication. It doesn’t stop us from predicting the average temperature in Rochester, NY in July will be, say, ~25 C warmer than the average temperature in January.
And, we don’t just have the instrumental temperature record to go on to understand the relation between radiative forcings and climate response. We can look at changes that have occurred in the past, such as ice age – interglacial periods. We can look at responses to volcanic eruptions. We can look at the pattern of the warming that we are seeing. And, yes, we can create models using the best current understanding of basic physics, such as the fact that as ice and snow melts the reflectivity of the Earth decreases and that as temperature rises, there is more evaporation of water.
Is it a difficult problem, with lots of uncertainties and potential surprises in store? Absolutely. Is there nothing that we can say about it besides, “Oh well, climate changes…Sometimes it gets warmer and sometimes colder and there is no way we can no why”? Absolutely not.
And, the best people to decide what the current state of the science is are the scientists in the field. We have accepted ways to evaluate the state of science in the field that have served us well and we should not abandon them to Professors of Marketing simply because they give us an answer that may be more appealing.
I know, I was just going to stand by and have popcorn with RSC, but…
“joeldshore says:
October 16, 2013 at 1:39 pm
…
As per the Oregon petition, the basic facts, as Park well-described it are these:
(1) The paper and petition were mailed en-mass to members of various scientific departments at universities (and perhaps other places) and only YES votes, i.e., people who chose to sign the petition were counted.
(2) The paper was formatted in a way and Seitz noted his position as a past President of the National Academy of Sciences in a way that was sufficiently deceptive that NAS felt compelled to issue a statement that said that the paper had not and was not even being considered to appear in their proceedings and that the claims in the paper were in contradiction to the Academies own conclusions.
Point #1 – they only counted the returned, signed petitions as people who signed the petition! What is wrong with that? Doesn’t every poll or survey only report on the answered questions?
Well, now that I think about it, maybe not – isn’t the “97% consensus of all climate scientists” really just an assumption that they all agree? I guess Alarmist’s have models that predict the responses, thereby alleviating the need to actually poll or survey anyone.
Point #2 – I’ve gone to the Petition Project website and seen what they sent out and do not see where it was stated that they were including a NAS paper. Even so, I see nothing wrong with NAS pointing out that they (at least some in leadership at NAS) did not support the paper.
Much ado here about nothing.
OK, back to the popcorn.
Apologies to Richard that I left him eating alone.
Is it a difficult problem, with lots of uncertainties and potential surprises in store? Absolutely. Is there nothing that we can say about it besides, “Oh well, climate changes…Sometimes it gets warmer and sometimes colder and there is no way we can no why”? Absolutely not.
Actually, I think that this is very close to being the case. I’d be very interested in your explanation of the cause of the MWP and the LIA (in particular the latter) in the event that you disagree. As well as the reason for coming out of the ice age. As well as the reason that that reason stopped in 1950 to be smoothly replaced by CO_2 so cleverly that nobody can tell the difference between the first half and second half of the 20th century from a peek at GASTA alone unless they already know the curves by heart.
The problem is that it is all too easy to point to something and say, “Look, if we increase albedo, we’ll have thus and such effect” in a one dimensional model. Albedo reflects energy, it appears in simple 1-D power flow models in a very clear context, it appears that it can do nothing but produce a single result. But the climate is full of negative feedbacks and plain old noise. It has multiple reservoirs with very disparate relaxation times and mechanisms. Albedo itself isn’t linear and independent of frequency or context. JUST because one increases an “albedo” number one generated as an average somehow, or decreases it, does not imply that there is going to be a certain response over any time at all. If it were that simple, the Earth would be a giant snowball.
Similarly, one cannot just say “We’ve increased carbon dioxide, therefore we are certain to get a particular temperature response. This temperature response is certain to increase the humidity, which will further increase the temperature response, which will increase the CO_2 still further as the ocean warms which will increase the humidity etc.” The humidity ALREADY fluctuates enormously, and if it had positive feedback on temperature alone it seems likely that positive fluctuations would have the potential for runaway warming.
Only they don’t, both because it is not clear that the primary assertion is true — that increasing GASTA increases humidity in the first place and because it takes time for the system to respond and the humidity definitely has negative feedbacks that remove it as it is added. Suddenly what you thought was a simple problem in balancing fixed linear rates with simple assumptions has become a dynamics problem with autocorrelation times and decay rates and with the possibility of nonlinearities that almost completely remove your presumed linearized effect. One rather EXPECTS those negative feedbacks to exist because the climate is if anything remarkably stable over geological time. With the exception the currentype age, of course, which is geologically tied with the OS-transition for the coldest period in the last 600 million years, interglacial and all (and where the OS transition and ice age occurred with over 10x as much CO_2 in the atmosphere as there is today).
Which doesn’t mean that I do claim to understand this or mean that this is necessarily significant. I rather do not. I just think that you are imagining a set of partial derivatives on a complex hypersurface permit you to predict chaotic orbits around constantly moving attractors and don’t appreciate the true complexity of the problem.
Either way, GCMs are supposedly the best we can do computationally, and they are not completely naive or one dimensional. Rather they are complex out at the limits of our ability to compute. Do they yield a uniform result? No, they don’t. Not even when applied to a toy problem with none of the complexity of the real Earth. Are they initialized with the same parameters? No, if they were they wouldn’t even fit the training data. They are individually tuned to fit that data, and consequently tend to give very different predictions outside of the training set. Do they give a consistent result from run to run for small perturbations of the initial conditions? No, they actually fill in a rather staggering range of possible futures, some of which actually cool (from what I can tell from looking at examples in AR5). Can one average over the set of GCMs and get a more reliable prediction than the unreliable prediction produced by any particular GCM? No, this is an abuse of statistics and absolutely unsupportable from first principles.
I’m trying to figure out why you think the GCMs are reliable, given this as their current track record. Oh, and then if one actually deconstructs all of the individual GCM results in figure 1.4 of AR4’s SPM, how many of them would be rejected on the basis of a hypothesis test? Certainly all of the warmest ones, and there are few of the GCM results that anybody would be comfortable asserting as a good approximation of just GASTA.
Look, I’m actually pretty open to the hypothesis that humans, by increasing atmospheric CO_2 by some unknown but estimated amount (amount subject to the model used to perform the estimation) have increased GAST by some amount (amount HIGHLY uncertain, because we cannot even compute GAST to within an interval smaller than roughly 1% of the absolute temperature). I think that even with the uncertainties, it is reasonable to think that there has been warming of less than 1 C over the last 170 years of arguably computable thermometric records (with rapidly increasingly uncertainties as one moves back from the present, where we don’t have that good a handle on the present). I simply do not think that it is possible to, at this time, make any assertion whatsoever as to what fraction of the overall observed increase — with all of its uncertainties — is due to the supposedly anthropogenic fraction of the CO_2. I especially doubt any assertion that the climate would have been neutral or cooling from 1950 on without CO_2, as that really is an absurd claim, but it does tie right back up with your belief that we can and do know why the climate warmed from (say) 1850 to 1950. Well, actually, warmed, then cooled some, then warmed a lot more, then just started to cool, then stayed nearly constant until the 70’s, then went up the same general way it did in the 20’s and 30’s, then peaked, and now appears to be descending much as it was in the early 50’s.
I also do not agree that the AR5 SPM should have changed/eliminated the wording that made it clear that the deviation of the real climate from the simulated climates is a problem. I do not agree that the models in CIMP5 that aren’t within a half of a degree of the actual GASTA — let alone the GAST that they predict but never ever actually show — should be included in AR5 as if they are just as reliable as all the rest and hence just as reasonable a contribution to the supposed mean!
I know that you are actually a reasonable person, and I appreciate it when you correct me when I make an egregious error in my statements. That’s what people are supposed to do. You also are at least somewhat open minded, from our previous conversation in a variety of contexts. That’s why I am puzzled that you don’t seem to care when I point out these fairly specific problems with AR5 and GCMs in general. We aren’t really arguing about whether or not the GHE exists or global warming has occurred. What we are arguing about is whether the claims of near certainty that are being made in a specific document, AR5 SPM, are well founded on the basis of statistics and common sense or are deliberately misrepresenting the actual quality of the actual results of the actual GCMs, considered one at a time and compared critically to the observational data of the real world after the time they were initialized and run.
We are also arguing about (perhaps) whether the GASTA as produced by HADCRUT4 (as one of many that do not all agree in spite of having what one assumes is a substantially overlapping data foundation) in and of itself supports the simple observation that there is a strong and apparent correlation between atmospheric CO_2 concentration and temperature. I think that it is rather evident that it does not — if anything, it suggests the opposite, that negative feedbacks very likely cancel nearly all of the warming one DOES expect from the excess CO_2, because the structure of the 170 year GASTA curve doesn’t undergo the slightest change as CO_2 “turns on” in 1950.
“Suggesting” isn’t the same as “proving”, but it is still an important point. The climate is, in fact, not behaving the way one naively expects from all of the naive arguments, nor is it doing what the GCMs predict with their highly nontrivial, non-naive (but as a consequence, more easily mistaken) arguments. I do not know, but I am not convinced that the GCMs are correct, and I am FAR from convinced that any naive argument is likely to be any more correct than numerology on HADCRUT4 of the sort that I’ve already portrayed.
Why, exactly, do you disagree with this? A lot of very reasonable climate scientists are starting to back off their claims of climate sensitivity, and it was never the case that the majority of climate scientists agreed with “catastrophic” anthropogenic GW, but rather with some degree of AGW that might be anything from net positive to mildly neutral as far as negative consequence is concerned. Also, I repeat — how long does the climate have to remain near neutral before you agree that there is a problem with at least some of the GCMs? Do you agree that this point has already been reached for at least some of the GCMs?
These questions are the ones I’d love to hear you answer, because they’d give me some feeling for what evidence you would consider sufficient to start to NOT strongly believe the predictions of disaster. I’ll tell you straight up what I would consider as evidence FOR the predictions of disaster — the GASTA increasing by 0.3 to 0.5 C quite rapidly to get it back on track with the GCMs. Do you really think that this is about to happen?
rgb
rgbatduke says: It is like asserting that a nonlinear system that is following a poincare cycle in some ten or twenty dimensions that has a clearly evident and easily computable four parameter secular trend.
We’re only looking at the global mean surface temperature. That parameter is largely constrained by conservation of energy, radiative changes, and ocean currents. It’s not a poincare cycle, because there’s net energy into the system at the top of atmosphere, because of CO2 increases.
rgbatduke says: c) Dr. Soon, in fact, has done and published climate research. He has a physics Ph.D. He AFAIK is employed by Harvard, which is not exactly the easiest institution in the world to get tenure in.
There are over 100,000 scholarly papers on climate change in the peer reviewed literature. The qualifications of one contrarian, (and Linzden should be your poster boy), do not make academic weight. In round numbers, since the early 90s at least there have been about 0 scholarly papers (http://www.sciencemag.org/content/306/5702/1686.full), and about 0 scientific bodies of national or international standing (http://en.wikipedia.org/wiki/Scientific_opinion_on_climate_change#Dissenting) that support the contrarian position.
rgbatduke says: so much so that if one presents the curves side by side and asks someone to identify which one came from the CO_2 era it is a bit tricky to do so!
The response of the global mean surface temperature to an increase in CO2 takes 40 or 50 years for 60% of the change to have occurred. Looking naively at the graphs won’t spot the interrelationship.
JohnWho says:
Do you not understand the difference between a survey that says “Answer yes or no to these questions and return the survey” and a petition that says effectively, “Return this if you agree…and if you don’t agree, we have no desire to hear from you and no means by which to record your disagreement anyway.”
There are at least 2 polls that I know of done in at least a reasonably scientific manner (for example, here: http://stats.org/stories/2008/global_warming_survey_apr23_08.html ) Are they perfect? No, but it is ironic to see AGW skeptics nitpick the details of how the question was phrased in some poll and then turn around and say, “But..;look at this Oregon Petition…” It speaks volumes to the double standards
You didn’t see the mass mailing that was done in 1998. The NAS does not go around regularly issuing statements that a paper is not published by them and does not reflect their views; the fact that they felt the need to do so in this case lends further support to Robert Park’s description of the deceptive way in which it was presented.
And, another thing worth pointing out is that the petition project is now 15 years old. So, it is not even like the signatures are recently collected. Back in 1998, I was myself was still pretty ignorant regarding the science of climate change…There was much more room to be ill-informed regarding the general conclusions of the scientific community than there is now. It’s not even clear how many of the signers over the years would still re-affirm their opinion now. But, there seems to be no expiration date on the signatures.
R. G. Brown at Duke
*****************
Yes.
joeldshore says:
October 16, 2013 at 4:31 pm
Taking your points one at a time:
“Do you not understand the difference between a survey that says “Answer yes or no to these questions and return the survey” and a petition that says effectively, “Return this if you agree…and if you don’t agree, we have no desire to hear from you and no means by which to record your disagreement anyway.””
Not exactly. They didn’t simply say “return this if you agree” they said “return this if you are willing to sign you name at the bottom of this petition”. No anonynimity there. Huge difference.
“There are at least 2 polls that I know of done in at least a reasonably scientific manner (for example, here: http://stats.org/stories/2008/global_warming_survey_apr23_08.html )”
Interesting. The title of that article is “Climate Scientists Agree on Warming, Disagree on Dangers, and Don’t Trust the Media’s Coverage of Climate Change” and much of the article isn’t really at odds with the Petition Project statement “There is no convincing scientific evidence that human release of carbon dioxide, methane, or other greenhouse gases is causing or will, in the foreseeable future, cause catastrophic heating of the Earth’s atmosphere and disruption of the Earth’s climate.” The “catastrophic” part being the most germane.
Without seeing the exact wording of the questions, one should be skeptical of the results. That is, one with an open mind, anyway.
“You didn’t see the mass mailing that was done in 1998.”
Did you?
I don’t see the deception in what is available now, but I do support NAS’s pointing out that they did not support the paper.
“And, another thing worth pointing out is that the petition project is now 15 years old. So, it is not even like the signatures are recently collected. Back in 1998, I was myself was still pretty ignorant regarding the science of climate change…There was much more room to be ill-informed regarding the general conclusions of the scientific community than there is now. It’s not even clear how many of the signers over the years would still re-affirm their opinion now. But, there seems to be no expiration date on the signatures.”
Other than replying the obvious; that you still are pretty ignorant regarding the science of climate change, I would ask you the following:
Do you know whether one can ask to have their signature removed? Unless you are positive one can not, I would say your comment bears no weight.
Joel Shore says:”We can look at changes that have occurred in the past, such as ice age – interglacial periods.”
Where we observe that changes in co2 lag around 800-2700 years behind changes in temperature.
“at frequencies where there is significant coherence between the records, atmospheric CO2 lags, or is at most synchronous with, dV/dt. In other words, variations in melting precede variations in CO2. Thus, the relatively small amplitude of the CO2 radiative forcing and the absence of a lead over dV/dt both suggest that CO2 variations play a relatively weak role in driving changes in global ice volume compared to insolation variations.” Roe 2006
And we also observe that the rate of change of (de)glaciation correlates remarkabky well to changes in 65N Insolation as the Earth’s orbit changes shape and the the equinox precesses
http://tallbloke.wordpress.com/2011/05/28/ice-ages-driven-by-earth-orientation-changes-not-co2/
“variations in summertime shortwave forcing exceed the direct CO2 radiative forcing by about a factor of five.” Roe 2006
So lets talk about forcings some more, because you might learn something. Eventually.
rgbatduke and joeldshore:
In making arguments in this thread, the two of you use “predict” and related terms. These terms are polysemic (have more than one meaning). When an argument is made, the presence in it of polysemic terms can lead to conclusions that are false or unproved but that seem to be true. In particular, the presence of polysemic terms in your arguments can lead to conclusions that are false or unproved but seem to be true. You can alleviate this concern by sharing with us what you mean by “predict.” What is it?
>JohnWho says:
>October 16, 2013 at 7:10 am
>>Seth says:
>>October 16, 2013 at 5:32 am
>>Some of the fake names that were in the petition:
>>Do you even realize how foolish you are?
The point is that there is no vetting on the names, and while some obvious fakes that have been pointed out in the media have been removed, that does not raise confidence in the verification process, that they infamously refuse to give any details about. Quite the opposite.
I’m not sure why showing that the system is flawed is foolish. I can only suspect motivated reasoning. But for any honest person, the powerful fact that it was accompanied by a fraudulent paper would be strong enough evidence to distance them self from it. You should be embarrassed to defend it. It embarrassed me to see it mentioned, and I don’t even associate my intellectual position with theirs: It’s embarrassing that it was done by humans.
Having said that, no, I don’t realise that point that out makes me foolish. Is there anything you realise about supporting it?
re: “If this were any other problem in physics with similar complexity, nobody would be announcing success, and nobody would be betting a trillion dollars and millions of lives on the predictions of the not-yet-successful models.”
I think that the policy is based on the optical properties of CO2, not the predictions of models. It doesn’t matter how quickly or slowly the temperature reaches the equilibrium, or if the equilibrium climate sensitivity is 1.5 or 5°C per doubling. It’s still cheaper to engage in amelioration than adaptation.
Seth says:
October 17, 2013 at 5:33 am
I think that the policy is based on the optical properties of CO2, not the predictions of models
Well if that’s true then the cli-sci advocates and policy makers really do need a good kick up the backside. The optical properties of co2 in the lab belljar tell us nothing about its effect in the open atmosphere where it is 0.0004 of the mass and is hugely overwhelmed by the action of latent heat transfer through the convection of water vapour.
There are over 100,000 scholarly papers on climate change in the peer reviewed literature. The qualifications of one contrarian, (and Linzden should be your poster boy), do not make academic weight.
Sorry, I already have this square on my bingo sheet. Well, squares, really.
There are some really pithy quotes from both Bertrand Russell and Einstein here one is tempted to cite, but why bother. Even if the experts do all agree, they can still be mistaken, and historically often have been. And this still is not an argument.
As far as poincare cycles go — perhaps we fail to understand the consequences of nonlinear mixed positive and negative feedback and the manifest at least bistability if not multistability of the Earth’s climate system. Perhaps we should read a few of Koutsoyiannis’ papers on Hurst-Kolmogorov dynamics, and meditate upon Bob Tisdale’s lovely graphs of SSTs advancing and retreating stepwise. Perhaps we also might note that small changes in atmospheric circulation patterns and cloud based albedo alone are sufficient to compensate for the extra forcing produced by CO_2. Finally, we might note that we have been hammered repeatedly over how the heating of the 1980s and 1990s was all due to the extra atmospheric CO_2 that began in the 50’s, and now here you are telling me that all of that heating was just 20-30% of the heating from the previous 30 years, if that, and then in 2000 it just stubbornly STOPPED in spite of the fact that atmospheric CO_2 continued to rise. How is this possible, one wonders? Why is it that the GCMs make GASTA predictions that continue to rise but the temperature stubbornly does not?
If you argue that natural forcings are cancelling this predicted warming, then, well, we’re right back to poincare cycles and neglected causes in the models, which consistently underestimate the impact of natural variation BECAUSE they were all designed to make all of the warming in the 1980’s due to CO_2. Your own argument seems inconsistent. If it takes 50 odd years to see only half of the warming, then the warming we have seen so far has almost nothing to do with CO_2 (and in any event has paused for over a decade, consistent with a persistent cycle at least 170 years long). If it doesn’t, then it should be warming. Either way, it seems difficult to argue that the magnitude of the predicted warming and climate sensitivity are correct, and indeed there are scholarly papers that are busily reducing the sensitivity to better fit the new data.
We just don’t know how MUCH they will have to reduce it if the current flat patch continues. It is down in AR5 from AR4, and down from AR5 given the more recent data, to around 2, which is barely amplified from the 1 to 1.5 expected from CO_2 alone. Sure, maybe it will suddenly start to warm and spike way up in GASTA next year. Or maybe not. At the moment, the behavior of the climate is not strongly supporting the predictions of catastrophe.
rgb
tallbloke says:
Unfortunately, your lack of understanding of the science is causing you to take some technical discussion and misinterpret it in a belief that it supports your position when it does not.
You seem to be attacking a strawman version of the argument regarding CO2 and the glacial – interglacial cycles that goes something like this: “If we assume that CO2 is responsible for all of the change in temperature that occurs in these cycles, then that implies a climate sensitivity for CO2 in the IPCC range.”
However, the actual argument is this:
“As has been generally accepted since at least the mid-1970s, the glacial-interglacial transitions are initiated by Milankovitch cycles that redistribute the solar insolation over the Earth (without directly changing the global radiative forcing very much) in such a way that ice sheets grow and shrink and CO2 (& other greenhouse gas) levels change, although various details of exactly how this occurs are still being debated. The change in the ice sheet coverage and vegetation and the change in greenhouse gas levels then both contribute to a total global radiative forcing that can be estimated. (There is also understood to be a small contribution to forcing from changes in aerosol levels in the atmosphere.) Using this estimate of the total radiative forcing (of which only about 1/3 is due to changes in the level of CO2) and knowing the approximate global temperature change, the climate sensitivity can be calculated to be about 0.75 K per (W/m^2). Given the known forcing due to a doubling CO2, which essentially everbody, including Richard Lindzen and Roy Spencer, agree is about 4 W/m^2 +/- 10%, one finds a climate sensitivity of about 3 C per CO2 doubling (with error bars of roughly 1 to 1.5 C in either direction).”
The issue of the exact timing of the sequence of events in the case of these lacial glacial-intergcycles is still being debated, but has very limited relevance to the above argument. It is worth noting that Roe expresses just one opinion and a recent paper expressed a different opinion about the relative timing of the events: http://www.sciencemag.org/content/339/6123/1060.short
It is also worth noting that your out-of-context quote from Roe regarding the ratio of summertime shortwave forcing discusses variations in the local (in both space and time…i.e., seasonal) forcing and how they affect the initiation of the ice sheet growth or decay. It is not a discussion of the global radiative forcings and their effect on the average global temperature. That being said, as I already noted, it is generally agreed that the contribution to the global radiative forcing from CO2 is only roughly 1/3 of the total forcing, with the largest contribution coming from the albedo change due to the ice sheet growth and decay (and vegetation changes). [CO2 is, however, believed to play the important role of synchronizing the temperature change in the two hemispheres.]
So, basically, you have cherrypicked one paper, ignoring others, and then badly misinterpreted it to try to support a view that it does not support.
John Who says:
You might want to read beyond the title. To summarize some of the main points:
* 85% of the scientists surveyed believe global climate change will pose a very great danger or moderate danger to the earth in the next 50 to 100 years (with the split between very great and moderate being 41% and 45%, respectively); only 13% believe there is relatively little danger.
* 64% find Al Gore’s documentary film “An Inconvenient Truth” to be very or somewhat reliable (with the breakdown being 26% and 38%, respectively). By contrast, only 1% rate Michael Crichton’s “State of Fear” as being very reliable (they don’t say how many list it as somewhat reliable).
It is also worth noting that although they tend to characterize this poll as representing the views of the climate scientists, it sounds like the survey methodology (of finding members of either APS or AGU) actually surveys a broader sample of geophysicists and meteorologists. Other surveys have shown that generally the more you narrow down the sample to actual climate scientists in the field, the more strongly they agree on the issue of climate change. For example, the survey as constructed would have likely interviewed some broadcast meteorologists, who are generally known to be more skeptical of AGW than those working more closely in the climate science field.
I agree, which is why it is useful to read beyond the headline. It would be even more useful if they had a link to the exact survey questions and results, although I haven’t been able to find one.
However, this seems like rather one-way skepticism if one is very skeptical of this scientific poll conducted by a reputable organization but not way, way more skeptical of a completely unscientific petition conducted by people who strongly worked to get a desired result.
And yet, I am way more knowledgeable than almost all signers by the sort of metrics that the petition organizers have discussed, such as having a PhD and being in a physical science / engineering field. I am sure I am also way, way more knowledgeable than almost all signers in terms of having read scientific papers in the climate science field and having read textbooks on atmospheric science and climate.
The point is not whether one could remove one’s signature with a lot of effort, but rather whether the fact that one signed something 15 years ago should be taken as evidence that one still holds the same view. I would imagine that many signers might have had their views evolve but have not bothered to try to get their name removed. (Many may not even remember that they signed it…Or even know what became of it.) How many? We have no way of knowing because no effort has been made to my knowledge to see how representative this is of current views of the signers.
Seth:
The policy is based upon the equivocation fallacy ( http://wmbriggs.com/blog/?p=7923 ).
By the way, contrary to repeated utterances by rgbatduke, the IPCC climate models do not make predictions. They make projections. The appearance that they make predictions is created when people including rgbatduke conflate the two terms. By conflating them, they create a polysemic term from which they then draw improper conclusions via the equivocation fallacy.
tallbloke says:
Convection cannot get heat out of the atmosphere…only radiation can…and we know the limits of convection in equalizing temperature within the atmosphere, which are that it only operates until the lapse rate is reduced to the adiabatic lapse rate, beyond which the atmosphere is no longer unstable to convection.
The only way that your friends Nikolov and Zeller were able to get convection cause the radiative greenhouse effect to disappear in a simple model of the greenhouse effect was to force the atmosphere to be driven to an unphysical state where the lapse rate is driven to zero. You naively defended this as being somehow irrelevant even though it is easy to show (and easy to read in a textbook!) that it is EXACTLY what is relevant, and that the silly little nitty numerical details of how one implements convection that Nikolov & Zeller claimed to by relevant are in fact what is completely irrelevant.