Our favorite contrarian, the potty peer Christopher Monckton has been indulging in a little aristocratic artifice again. Not one to be constrained by mere facts or observable reality, he has launched a sally against Andy Revkin for reporting the shocking news that past industry disinformation campaigns were not sincere explorations of the true uncertainties in climate science.
The letter he has written to the NY Times public editor, with its liberal sprinkling of his usual pomposity, has at its heart the following graph:
Among other issues, it is quite amusing that Monckton apparently thinks that;
- trends from January 2002 are relevant to a complaint about a story discussing a 1995 report,
- someone might be fooled by the cherry-picked January 2002 start date,
- no-one would notice that he has just made up the IPCC projection curves
The last is even more amusing because he was caught out making stuff up on a slightly different figure just a few weeks ago.
To see the extent of this chicanery, one needs only plot the actual IPCC projections against the observations. This can be done a number of ways, firstly, plotting the observational data and the models used by IPCC with a common baseline of 1980-1999 temperatures (as done in the 2007 report) (Note that the model output is for the annual mean, monthly variance would be larger):
These show clearly that 2002-2009 is way too short a period for the trends to be meaningful and that Monckton’s estimate of what the IPCC projects for the current period is woefully wrong. Not just wrong, fake.
Even if one assumes that the baseline should be the year 2002 making no allowance for internal variability (which makes no sense whatsoever), you would get the following graph:
– still nothing like Monckton showed. Instead, he appears to have derived his ‘projections’ by drawing a line from 2002 to a selection of real projections in 2100 and ignoring the fact that the actual projections accelerate as time goes on, and thus strongly over-estimating the projected changes that are expected now (see here).
Lest this be thought a mere aberration or a slip of his quill, it turns out he has previously faked the data on projections of CO2 as well. This graph is from a recent presentation of his, compared to the actual projections:
How can this be described except as fake?
Apart from this nonsense, is there anything to Monckton’s complaint about Revkin’s story? Sadly no. Once one cuts out the paranoid hints about dark conspiracies between “prejudiced campaigners”, Al Gore and the New York Times editors, the only point he appear to make is that this passage from the scientific advice somehow redeems the industry lobbyists who ignored it:
The scientific basis for the Greenhouse Effect and the potential for a human impact on climate is based on well-established scientific fact, and should not be denied. While, in theory, human activities have the potential to result in net cooling, a concern about 25 years ago, the current balance between greenhouse gas emissions and the emissions of particulates and particulate-formers is such that essentially all of today’s concern is about net warming. However, as will be discussed below, it is still not possible to accurately predict the magnitude (if any), timing or impact of climate change as a result of the increase in greenhouse gas concentrations. Also, because of the complex, possibly chaotic, nature of the climate system, it may never be possible to accurately predict future climate or to estimate the impact of increased greenhouse gas concentrations.
This is a curious claim, since the passage is pretty much mainstream. For instance, in the IPCC Second Assessment Report (1995) (p528):
Complex systems often allow deterministic predictability of some characteristics … yet do not permit skilful forecasts of other phenomena …
or even more clearly in IPCC TAR (2001):
In climate research and modeling, we should recognize that we are dealing with a coupled non-linear chaotic system, and therefore that the long-term prediction of future climate states is not possible. The most we can expect to achieve is the prediction of the probability distribution of the system’s future possible states….
Much more central to the point Revkin was making was the deletion of the sections dealing with how weak the standard contrarian arguments were – arguments that GCC publications continued to use for years afterward (and indeed arguments that Monckton is still using) (see this amendment to the original story).
Monckton’s ironic piece de resistance though is the fact that he entitled his letter “Deliberate Misrepresentation” – and this is possibly the only true statement in it.
Barry Foster writes:
Global warming will cause more droughts in continental interiors, more violent weather along coastlines, the destruction of glaciers which provide fresh water to a billion people in Asia and Latin America, and eventually, the loss of trillions of dollars worth of infrastructure due to sea-level rise. If we lose our agriculture, human civilization will collapse. I find that worrysome, but maybe that’s just me.
Why don’t you try doing a linear regression of the figures against time, inste4ad of “[l]ooking at the graph?”
re 135.
Are you saying that John faked the Heartland website to show that they both argue that AGW is false and that tobacco being harmful is false?
Otherwise I see no cliff.
PS Are you in Egypt at the moment?
In #98 Jim Eager said “There’s your first problem right there: you’re not looking at a trend in climate.” Correct I’m looking at a trend in a time-series based on physically measured quantities used to present evidence for climate change. So how is that a problem?
Then he said “Your second is thinking that you know anything about statistical analysis.”
But I do, so how is that a problem?
Then he said “As Gavin said, in science cherry-picking and making sh*t up is frowned upon. I know, kind of antiquated in our age of ‘padded’ resumes, claims of being IPCC ‘expert reviewers’, Nobel prize holders, and members of the House of Lords.”
So searching for potential counter-examples to a multi-disciplined physical theory’s predictions is cherry picking is it? I thought it was the basis of scientific critical analysis.
Thomas, a picture:
http://www.globalwarmingart.com/images/thumb/2/26/Greenhouse_Effect.png/300px-Greenhouse_Effect.png
Few photons — infrared — go directly from the ground to space.
134 Thomas Donlon
I sure somebody will correct me if I’m wrong, but, I think the problem with your camera filter analogy is that the camera is measuring light transmitted through the two filters whereas in the greenhouse situation, light passing through the “filters” is absorbed, re-emitted at a different frequency and is trapped behind the double filter. So a doubling in CO2 will do little to stop more energy coming in, but will do a lot to stop it getting out.
Gavin, yes there were a lot of factual errors in my two simple sentences. I want you to know I appreciate not only you pointing that out to me but also the polite manner in which you did so.
John Mashey said in #132:
The similarities between the manufactured controversy created by the global warming “sceptics” and other recent anti-science campaigns (tobacco, intelligent design, AIDS dissent in South Africa and so on) are striking. There is an excellent article on this by Leah Ceccarelli from the University of Washington:
Manufactroversy – The Art of Creating Controversy Where None Existed:
I think it sums things up very well indeed. It is easier to undermine the established science, create an appearance of controversy where none exists, exaggerate the uncertainties etc etc than to defend the science with all of its inherent complexity. This is why sophists like Monckton can gain traction in some circles. And this is why a clear and well-communicated response from the scientific community is important to counter all the nonsense. It is also clear that this is going to be an on-going battle; the sophists generating a manufactured global warming controversy are not going to disappear any time soon.
“any dissent by any scientist is then seen as evidence that there’s no consensus, and thus truth must not have been discovered yet.”
Stranger yet is that tired old meme: consensus isn’t science.
Then again, consistency of thought isn’t necessary if you’re trying to tear science down. c.f. the ID crowd.
Son of Mulder, The problem is that 7 years doth not a climate trend make. The data are simply too noisy to draw any conclusions based on such a short time period.
You claim to know something about stats. The fact that you draw conclusions without taking into consideration the noise characteristics of your data belies your claim.
Hamish, I’m not sure I understand your question. How would the observation of a trend in climate change science? It is a subject for scientific study, but it calls for the same methods as any other field of study.
Olympus Mons #99:
Why such a low standard?
Ray, 159, he doesn’t even calculate the error value in his regression of the line.
Isn’t that kind of a CORE feature of statistics? Statistical significance?
Ray Ladbury #160 said “The data are simply too noisy to draw any conclusions based on such a short time period.
You claim to know something about stats. The fact that you draw conclusions without taking into consideration the noise characteristics of your data belies your claim.”
It’s your claim that the data are too noisy. Is it the underlying global climate system that is too noisy or the collection method that provides that noise eg the paucity of global data and the process used to construct the numbers?
Using political methods in arithmetic.
UK politicians have commissioned the Stern report, set targets for future reductions in CO2 and proceeded with plans for more runways, roads and coal fired power stations. Most people would just shrug at these simple sign errors ; isn’t that what you should expect from politicans?
Monckton also has a target and it is designed to short circuit the CO2 problem by reducing the estimates of climate sensitivity. Starting from this goal he has been able to give a whole new meaning to the term “ends justify the means”. These are similar to the methods used by politicians but may be new in arithmetic.
In his more elaborate calculations he has included unstated assumptions, over-simplifed models,arbitrary correction factors and the attachment of more than one meaning (in the same calculation) to some quantitities such as emissivity, forcing and feedback. These rather elaborate pseudo-papers were characterised by having a high conjuring coefficient (cc) . So each new work had to be followed by several alternative forensic examinations with slightly different emphases.
But is there evidence of a downward trend in the cc? This new work discussed by Gavin is mainly a recycling of the trendy ‘short trend blunder’ combined with crude misrepresentations. That should make life easier. There also appears to be an upward trend in the credentials claimed on his behalf.
There is a big difference between the climate & smoking debates.
With smoking, the link be shown clearly via epidemiological evidence, to cancer & bronchitis.
The pro-smoking lobby used the lack of proof from animal experimental data to deny a link betwen lung cancer in humans & smoking.
A classic example of a model (Animal studies)not reflecting reality (Human response).
Another being that the rat model showed no evidence of teratogenicity with Thalidomide. Human tragedy followed.
Hank (143), those products did qualify as addictive in the old clinical sense — just not initially. (couldn’t make them all out but I assume they are the old elixers like heroin and cocaine.)
re: 163. As has been pointed out here many, many, many times, the standard period for climate trend statistical analysis is 30 years per the WMO, not any individual scientist. Has been for many decades (ever heard of “30-year normals” in reference to local temperatures?). Any shorter term “cherry picked” analysis is subject to “noise/signal” issues.
re 163.
There are several levels that can be used to determine noise.
1) Empirically.
Take more averages and when your variability between a polyfit and the RMS error to that fit cause a much smaller reduction, you have removed most of the noise.
Think of bandpass removal of noise (hiss) from LP records: remove the higher frequencies and the noise reduces.
2) Logically
Think of those things that you know are cyclical and pick a time long enough to hold those cycles to a mean.
So an 11 year solar cycle -> 30 years or more. 7 year El Nino cycle -> 30 years, 20 year PDO -> 50 years.
When you remove those cycles you can see the cycles or changes that are not being swamped by those.
And when you subtract that signal from the raw data you can see what effects those cycles have without the trend changes hiding their effects.
Think stellar composition worked by taking out He and H lines from stellar spectra and then seeing what the less abundant constituents are doing to the remaining deviations from the blackbody curve.
And, having worked this out, climatologists from decades ago arrived at 50 years.
Rather appropriately two generations, so reasonably concordant with human longevity. Anything shorter will hit YOU in the shorts. Anything longer will hit your grandchildren in the shorts.
Son of Mulder, If you are not familiar with the data and the advice of the World Meteorological Organization for drawing conclusions about climate (e.g. >30 years to establish a trend), then perhaps you should devote some time to familiarizing yourself with the data and the science before trying to make definitive statements about whether we’ve turned a corner or not.
Gavin,
I see the 55 model simulations, thank you. What I am looking for is a reference for converting the output of the simulations to the graph that you showed. Your post says that it was done the same way as AR4. Where in AR4 are you referring to? As an example what does the 95% mean? 95% of the individual annual values from all models, two standard deviations from the mean of the individual values?
Figure 10.29 of AR4 gives an uncertainty range for the various scenarios, would the method used for your figure converge to the same 1.7 to 4.4 value for 2090-2099 for A1B?
[Response: all runs were baselined to 1980-1999 as in AR4. 95% refers to +/-1.96*standard deviations of the anomalies at each year equally weighted. The graphs in AR4 averaged over each model before averaging to get the mean, I didn’t and might not have used exactly the same set of runs. This method gives 1.6 to 3.5 for 2100 under A1B (mean 2.7 deg C), which should correspond roughly to the AOGCM 5-95% line in fig. 10.29. But that goes from ~1.8 to 3.7 eyeballing it, not the values you quote. – gavin]
Igor Samoylenko (157), a very astute and impressive discourse… There is one minor but overlying difficulty, however. You basically (and I apologize for oversimplifying your words for the sake of brevity) describe processes or a set of procedures followed by the “good” guys and the “bad” guys. All that is well and good. But, you describe the good guys as those who share your well-thought out beliefs and the bad guys as those that don’t.
For example you could take many of Ceccarelli’s paragraphs (but, to be honest, not all) describing how the antagonists act and substitute it almost word for word to describe the protagonists. For example,
could just as easily be describing protagonists. (Which, BTW, would not make them “bad” guys.) I have seen in RC alone protagonist subscription to every one of those points.
It is not easier to undermine established science. It’s not necessarily easy to undermine even established junk science, witches, 2nd hand smoke and marijuana for example. It all depends solely on where the mind of the masses of people happen to fall, and, as discussed in other posts, that is almost impossible to scientifically or logically predict.
I see that there are many here confusing what HAS happened with what MAY happen if the computer models are correct. I don’t know why some haven’t learned. The fact is that we (those of us unconnected with the fields of science) were led to believe that we would be pretty much warming up a treat by now. But that clearly hasn’t happened. Back in 1998 with the temperature peaking, I must admit that I was more than a little worried. I’m absolutely sure that if someone had informed me that eleven years later there would be no continued rise in temperature then I would have been very relieved. Of course, the temperature has actually fallen slightly. Now, why don’t some of you (the less childish ones here) be honest and admit that you didn’t think that would happen? None of this excuses Monckton or anyone else of a fabricated graph. But you people must understand that computer models are fabrications too. It’s what MAY happen. Given what’s happened in the past 10 years then I’m afraid I’m in no mood to listen to anyone who THINKS that their predictions of future climate is correct. Just two weeks ago the media were intimating to the public that a portion of the world could be wiped out by Swine Flu. At my age I’ve come to realise there are people around who strangely like to predict doom.
Ray Ladbury. Sorry, and excuse me, but that is tosh. I didn’t see any of the [edit] waiting around for 30 years to pass before saying that the world was heating up as a result of man’s greenhouse emissions. [edit] want to wait 30 years now before admitting that temperatures are not rising alarmingly. How convenient?
[Response: Huh? 30 years ago, Jules Charney concluded that temperatures would rise by the end of the century and they did. And cut out the juvenile name-calling – it will just get deleted. – gavin]
Hank Roberts Says (6 May 2009 at 0:31):
“The old classic chemical definition of addiction led to new products that didn’t qualify as addictive…”
Which brings up an excellent comparison example: Coca-Cola, which (by urban myth at least) originally contained cocaine. So fast-forward to the present day, when the world market for carbonated soft drinks runs into multiple billions of dollars. The soft drink industry uses marketing techniques similar to those the tobacco industry used, such as making them appear “cool” and introducing them to children at an early age. They’re likewise implicated in health problems, such as tooth decay and obesity. People who form the habit of drinking them do not (at least from casual observation) often abandon the habit…
So, are soft drinks addictive? Why or why not?
> addictive, just not initially.
Exactly, it’s age-dependent. If people don’t start using the product when they’re very young, they aren’t that likely to get addicted to it. That’s the point of that six-page paper — sell to the young.
Thanks Gavin,
There are quite a few ranges discussed in AR4, I think the range you are referring to is AOGCMSs 5-95% (normal fit). The figure I quoted was from the last paragraph of page 810, which might correspond to the gray box in figure 10.29. (AOGCM mean plus 60%, minus 40%)
If it isn’t too much trouble could you email me the annual values for the models that you used? I’m curious to see what the range of outcomes are in those models, and how much annual variability there is. I’d appreciate it as it must have been a bit of a chore to extract that.
[Response: I didn’t extract these data, and the people who did requested I not distribute it further until they had finished their paper. Sorry. I recommend Climate Explorer for the analyses you suggest. – gavin]
Svet — Any cloud iris effect must be very small: interglacial 2 (the Eemian) was about 2 K warmer than now and likely interglacial 4 was even warmer.
I suggest using the search function on this site to locate the FAQs on climate models and earlier threads regarding clouds.
Why should people “admit to” things they never believed? People in the know knew what “El Niño” meant back in 1998, just as today we know what “La Niña” is.
What you’re really doing is projecting your own ignorance onto others who don’t share it.
Guess which corporation is the only legal importer of coca leaves today?
Of course now, by law, they’re required to remove the cocaine and related alkaloids, but you’re still drinking a coca-flavored product.
No, not physiologically. Nor was Coca-Cola back when it had relatively small amounts of cocaine in it, which entered the bloodstream fairly slowly through digestion.
Barry, what are you on about? In 1998 the science reports were that this was a highly unusual and unusually hot year.
They were not saying that was going to continue.
The weather is following the trends with their random variability leavened on top.
Try a little scientific rigour in your observations and you won’t appear so foolish.
The WMO says thirty years is the period to reveal climate trends. That is something I learned, thank you, from a reply to a question of mine, earlier, in a different RC discussion.
However, consider the quandary I find myself in.
I would like it that the CO2 theories of global warming were wrong. For if it was, I would get rid of my footling 1000cc Fiat, and my habit of walking to the shop each day (an hour and twenty minutes) “to save the Earth”. Then I would go out and swap the footling Fait for a BMW – taking advantage of the UK government’s “this year only” recession pump-priming £2000 for scraping a car over ten years old and buying a brand new shiny one. And I would drive to the shop. And impress my neighbour.
So I find myself in a strange situation.
I am torn between wanting the global temperatures to rise (thus preventing Gavin, clearly a nice lad, from ending up with egg on his face) and wanting temperatures to fall which is “good for the planet” (but this would put a big, big smirk on that awful twit Monckton’s face).
I am praying that this year, or next year, or at least the year after that, the global average temperatures will start to rise again. Essentially I am praying for signs of disaster and dramatic evidence of this soon, for at my age, I will probably be well dead before the thirty years of the WMO is up. So, PLEASE, dear Climate God, let the temperature graph rise once more.
So I sit by my computer watching for the latest HadCRU3t (or whatever) temperatures to come in rather like a junkie stockbroker glued to the FTSE 100 Share Price Index.
I would just like to note that addiction is a complex phenomenon that has both physiological and psychological components, some of which are not well understood. As such it is in contrast to the basic physical mechanism underlying anthropogenic global warming, which is a fairly simple and well-understood mechanism. There are not many useful parallels between them or between respective efforts to address them through laws and regulations.
On the other hand Rod B referred to “junk science” regarding “second-hand smoke”. And I would note that the science demonstrating that exposure second-hand tobacco smoke is dangerous and harmful is very solid, and the claim that it is “junk science” is a deliberate, calculated lie perpetuated by the same deliberate, calculating, industry-paid liars who have lied, for money, about the harm of first-hand smoke and who have lied, for money, about the reality of anthropogenic global warming.
And as with GHG emissions, in the case of second-hand smoke it is most curious that so-called “conservatives” are so concerned with protecting the “right” of some to poison others with impunity.
@ 172, Barry Foster.
If my tongue in cheek posting, which was written before I read Barry Foster @ 172, gets past the moderator (?) I have to say that I have much sympathy with Barry’s post.
As an environmental activist who started campaigning so long ago that when if one said “Global warming” 98% of the population quite reasonably said “What’s that?” the lack of a continuing rise in global temperatures is hard to handle. Having to now say “It takes thirty years to validate a climate trend rather than the climate noise” so “please wait for the rising trend to become re-apparent” frankly makes me feel a bit stupid.
So, I too, like Barry, would like someone at RC or with similar scientific clout, to say, “Yes, though we consider the science shows warming, nevertheless, the present dip is difficult, as we would have expected a clearer continuing rise”.
Signed: Worried activist, England.
OK Dhogza. My analogy was bad. I was using the term camera filters and I was thinking of color filters in general. There are kids science kits and old 3d glasses that will filter out all light except blue or red or yellow. Doubling these up will not double the absorption on the lines they already absorbed all the light from. The NASA spacecraft site said (see my comment #140 and or link for a larger context) “The second spectral range absorbs carbon dioxide much more strongly, so much so that almost all of the light in this part of the spectrum is absorbed completely as it traverses the atmosphere. Adding more carbon dioxide produces little additional absorption”.
So there are some wavelengths that reach maximum absorption. Perhaps Gavin acknowledged this when he mentioned the need to consider other factors like “pressure broadening” – and I don’t know what that is. The link he supplied didn’t really focus on CO2 it was about (WMGHG). I haven’t heard of that term before – but it includes a supposed increase in humidity that will accompany warming and this feedback is called “forcing”. I suppose that makes some sense – a cold winter day will have little humidity and a warmer day might be humid as the air can hold more water.
Mark at 147 wrote, “Uh, the change from 1 to 2 filters is a doubling. A change from 0 to 1 is infinite.”
What are you trying to say Mark? When something is 1 it is still 1. If an army has no weapons and someone gives them 1 weapon – the increase in percentage of the number of that weapon might be infinite – but it might not win a war for them. What you are trying to say and how it relates to climate or to what I wrote?
Hank Roberts, I appreciate your chart. Now, I have to understand the effect that additional carbon has on this sequence. Does additional CO2 slow the rate of atmospheric radiative heat loss into space – and hence contribute to warming?
Jaydee I think I understand why you arguing that incoming radiation acts differently from outgoing. The mechanism though that CO2 works on outgoing radiation – is your thinking like that I asked Hank about directly above?
I’d like to stick to science and anyone that wants to bring up science with me – please feel free. – and lets be mature and peaceable.
Hank, but that is just a silly non sequitur as James kinda points out. It’s along the same lines of proving that marijuana is a gateway drug because almost all cocaine users did pot first. They also did milk first. Marketing to the young to get long term customers is indicative of almost every consumer product out there. (maybe not Depends…) It says nothing about their addictiveness.
SecularAnimist, you’re correct about the analogy between AGW and addiction. I can’t remember how we made that transition. Though addiction causes are not fully understood as you point out, its manifestations and characteristics were quite well defined as a practical clinical matter – until recently changed by pols and zealots.
Sorry about the 2nd hand smoke example. I forgot for a second how that’s like waving a red flag in front of a bull. (Watch this space!) But thanks for helping make my point.
Thomas says:
“What are you trying to say Mark? When something is 1 it is still 1”
Yes but when it was 0 a 1 is not still 0.
And double 0 is what?
Zero.
Therefore the change of no filter to 1 filter is not the same PROPORTION of change (which is the consequence of the LOGARITHMIC addition of extinction of photons) as 1 filter to 2.
Therefor expecting that changing from no filter to 1 to be the same change as 1 filter to 2 is incorrect.
Double one filter is two filters, but half of one filter is not no filter.
Therefore your “analogy” is incorrect: they are not assuming logarithmic (or geometrical) addition.
Is this maths too complex for you? If so, I can make it even simpler.
re 182.
Do the maths. Fit a curve of CO2 rises to that graph. Scale that appropriately. Now subtract that modified CO2 curve from the temperature figures (you’ll need to use a log of the CO2 concentration since one is a log-linear relationship).
Then compute the root mean square of temperature from that baseline.
Minimise that RMS value by changing the proportionality constant.
Now, what is that RMS difference?
Is the dip at the end of that graph within 3 times that value from the fitted CO2 graph?
If yes, then that is not a significant deviation from the graph: there is at least a 1% chance that it’s just random and not significant.
And out of 150 years, you’re likely to see 1 or two such years.
This is called a very rough statistical significance analysis to the theory that the log of CO2 concentrations is proportional to the temperature effect from that greenhouse gas.
Rod B wrote: “… you’re correct about the analogy between AGW and addiction. I can’t remember how we made that transition.”
It started when someone pointed out that some of the same corporate-funded, so-called “conservative” think-tanks and denizens thereof who are nowadays paid to lie about the reality of anthropogenic global warming were in the past paid to lie about the carcinogenicity and addictiveness of tobacco smoke. No analogy there, just simple fact.
Re: #183 (Theo Hopkins)
You’re mistaken. The present dip is NOT difficult and it’s NOT unexpected, it’s perfectly consistent with random fluctuations superimposed on a steady trend. In fact, it’s the nature of random fluctuations that it’s not just *possible* for apparent dips to happen for no other reason that randomness, it’s actually *inevitable*. Global warming is a trend superimposed on random fluctuations.
If the random fluctuations stopped, and we actually saw nothing but a “clear continuing rise,” THAT would be difficult to explain. The fact is, temperature is changing exactly as it’s expected to in a warming world. The fact that is fluctuates is expected; using those fluctuations to imply that global warming isn’t real, is either ignorance or dishonesty.
RodB, 185, what point? The only point I could see is that you will not see tobacco as bad. Rather like you won’t see human power generation from fossil fuels bad.
When you have something other than hand-waving about how eeevil the scientists were in redefining “addictive” to include things that were chemically addictive (as in your body needed them to continue to operate normally) maybe you’ll have a point.
tamino wrote: “The fact is, temperature is changing exactly as it’s expected to in a warming world. The fact that it fluctuates is expected …”
Indeed, intuitively I would expect that during a period of rapid warming and consequent rapid climate change, that there would be more fluctuation than normal.
> Does additional CO2 slow the rate of atmospheric
> radiative heat loss …. ?
Thomas, do you have time to read the FAQs? Lots of people will answer but none of us is likely to give you the understanding you’ll get from reading where the basic questions were answered well earlier.
Several ways to start:
1) First link under Science, right hand side, is a comprehensive book by Spencer Weart, with links.
2) “Start Here” link at the top of the page.
3) Google Scholar, pasting in your question:
http://scholar.google.com/scholar?sourceid=Mozilla-search&q=Does+additional+CO2+slow+the+rate+of+atmospheric+radiative+heat+loss+into+space+-+and+hence+contribute+to+warming%3F
Also, just now there is a protracted solar minimum, the likes of which has not occurred since 1913 CE. Despite this, 2008 CE was tenth warmest in the record. What rank was 1913 CE?
Clearly waqrming of the centennial scale continues.
Tamino @ 189.
Tamino. Thanks for your reply, but please be sympathetic to my problem.
Now, to start with, I fully accept that an increase in CO2 in the Earth’s atmosphere will – all else being equal – lead to a rise in temperatures.
Secondly, I fully accept that there are industry charlatans out there who will do everything possible to deny AGW for reasons of profit. And there are nutters out there, as well, who genuinely consider AGW (in Europe) a soc ial*list federalist EU scam allied to eco-fascist greenies to get us all to wear knitted yoghurt hair shirts and raise taxes. (In the US you talk of big tobacco: in Europe it was lead in petrol – the “Seven Sisters” disputed the science that lead can fry kids’ brains, questioned the methodology, said lead-free would cost four times as much so bringing industrial collapse. And cars would not be able to go over 70mph. And lead free would burn out your valves and blow your engine).
And I understand the concept of signal and noise.
I also understand that the high temperature in 1998 was due to the occasional El Nino.
However, the trouble is, that if you strip out 1998, the temperatures look more or less level since 1999.
Now it could be that there is an unknown carbon sink. (Though clearly I am only postulating this as unknowns are, of course, unknowns). But there _could_ be.
Nevertheless, how do you show the “man on the Clapham omnibus” (Being UK speak for Ordinary Joe) that there is still a problem?
You talk of random variations, so I guess the question is when Omnibus Man asks is: could it be that these random variations are hiding a downward trend? .
However, again dealing with Omnibus Man, can you imagine what will be going though his mind when I say “Just hang around for thirty years as that’s what the World Metrological Organisation says is trend, not a downward blip”.
What I am asking is: how to answer very ordinary people who ask perfectly reasonable questions like “Ger offit, mate, the graphs are level. S’stopped, ain’t it?” (This being my poor attempt at the Clapham accent of south London). That is, what is my answer? That’s without having to tell the man he may have to wait thirty years for an answer. For what Omnibus Man sees is not what the professional sceptics and the Moncktons are telling him – just that he has vaguely seen some graph somewhere and has independently drawn his own “common sense” conclusions. And he then puts this “common sense” against “what scientists say”.
((Meanwhile I’m taking a very carefull look at HadCRUT3 for the first time))
re: #182 Theo Hopkins, #172 Barry Foster
Tamino (#189) has done many great posts on this at Open Mind.
Just in case someone simply disbelieves temperature series, and disbelieves NASA GISS, Hadley, etc, I created a humble Excel spreadsheet example @ Dot Earth, post #114.
It has only a few simple, visible parameters for trend and random noise. An Excel user could replicate this from the recipe in 10 minutes, and have a model they’ve created themselves with no magic behind he curtain. Default parameters make yearly noise outweigt yearly trend, which (very) grossly resembles the real world. People can play with the noise parameter to see what it takes to make downturns disappear.
Capital Climate did replicate it, showing one run. Then he animated it, so that it repeatedly generates random runs to produce an ensemble, in FAQ here.
a) Even in a strong bull market, stocks don’t just rise monotonically, with no dips.
b) In going from Spring to Summer, noon temperatures don’t just smoothly increase.
Tamino does much more sophisticated analyses, but
understanding the basic idea is just minimal statistical numeracy; in some places they teach time series analysis to ~18-year-olds, so it can’t be that bad.
Re 183
Thomas Donlon Says:
6 May 2009 at 3:22 PM
OK Dhogza. My analogy was bad. I was using the term camera filters and I was thinking of color filters in general. There are kids science kits and old 3d glasses that will filter out all light except blue or red or yellow. Doubling these up will not double the absorption on the lines they already absorbed all the light from. The NASA spacecraft site said (see my comment #140 and or link for a larger context) “The second spectral range absorbs carbon dioxide much more strongly, so much so that almost all of the light in this part of the spectrum is absorbed completely as it traverses the atmosphere. Adding more carbon dioxide produces little additional absorption”.
So there are some wavelengths that reach maximum absorption. Perhaps Gavin acknowledged this when he mentioned the need to consider other factors like “pressure broadening” – and I don’t know what that is.
Below is a plot of a portion of the CO2 absorption spectrum, the top plot is for Martian conditions and the lower for Earth conditions, the substantial broadening of the latter is mainly due to pressure.
http://i302.photobucket.com/albums/nn107/Sprintstar400/Mars-Earth.gif
Re: 177 David B. Benson
Thank you for the reply. The “FAQ on climate models: Part II” says of clouds
However, I was hoping to get some clarification on Spencer’s statements that
A) “the main reason the models produce so much warming depends upon uncertain assumptions regarding how clouds will respond to warming”
[Response: This is inconsistent. There certainly are uncertainties to cloud modelling, but it there is no reason why uncertainty should favour one sign of feedback over another. It’s important to note that the sign of the feedback is not plugged in as a direct input but is an emergent property of the final solution that takes into account warming, changes in stability, changes in circulation, changes in humidity – all of which are also affected by the change in the clouds. One recent paper that you might find interesting is (submitted) by Trenberth and colleagues where they note that there is a systematic under-estimate in many models cloud cover in the southern ocean region. As the planet warms, these areas generally become more cloudy and since this is low cloud, it makes the overall feedback more negative. However, if they models had more cloud to start with, then the scope for making even more cloud would be limited, and thus one would expect more realistic models to have more positive cloud feedback! Now this is just one component, and there are many complications – but assuming that error and uncertainty imply a larger feedback is just illogical. – gavin]
B) “the warming in the models, however, is now known to be mostly controlled by the low and middle level clouds – the ‘sun shade’ clouds”.
If only some of the effort RealClimate puts into addressing Christopher Monckton could be put into addressing Roy Spencer. Spencer suggests that climate models are “mixing up cause and effect” when they deal with clouds. Is this possible or not?
[Response: Models don’t mix anything up – they are mechanistic models that are strictly causal – if a cloud appears it affects radiation and climate, and if climate changes than that can impact clouds. Spencer’s broader point that climate sensitivity is too high because of some analysis of satellite data is also confused. Charney’s estimate of 3 deg C, or Hansen’s estimate from the last ice age all predate substantive satellite analyses and are not affected by anything Spencer is talking about. This is not acknowledged anywhere by Spencer and is one of the reasons why his analysis is likely to be flawed (or at best, incomplete). – gavin]
Svet (197) — I’m an amateur here and just learning the meteorological aspects. But somehow I expect the modelers understand their models and certainly do not “mix up cause and effect”. Gavin Schmidt has at least two review papers (at least one co-authored) on his publications page. You could try there. Or as Hank Roberts is want to suggest, use your search engine to look for papers which address your (carefully formulated) question.
I’m quite content to just stick with the FAQ for now.
Svet (197) (also Gavin’s response) — Regarding climate sensitivity I actually know a bit. First of all, there are many different climate sensitivites, depending upon time scale and forcing: transient climate sensitivity (TCS) is about 70 years; Charney’s equilibrium climate sensitivity (ECS) requires over a millenium to reach equilibrium. More recently it became necessary for me to introduce the solar cycle climate sensitivity, measured over about 5+ years; the work-up is found in the “Climate sensitivity, Shaviv and Tung et al” thread of the globalchange blog, listed in the Other Opinions section of the sidebar. Being a shorter time, the response is only about 60% of ECS; TCS is about 67%.
Spencer, in at least one writing, estimates a climate sensitivity based on intra-seasonal data! Naturally, it is quite small and cannot, IMO, be used to provide any form of estimate for ECS, just an obvious lower bound.
Ray Ladbury, in your #169 you didn’t answer my question from #163 ie “Is it the underlying global climate system that is too noisy or the collection method that provides that noise eg the paucity of global data and the process used to construct the numbers?”
Between Dan in #167 and Mark in #168 they have respectively suggested 30 years and 50 years to establish a trend? Which if either is reasonable and why?
Mark in #167 suggests a polyfit is required, why not a harmonic analysis as we’re dealing with the resultant of cycles? Also in your Hi-Fi analogy is the ‘hiss’ from the record or the amplifying system? Quite important as I’m trying to establish what is actually meant to be on the record.
If I take the 30 year suggestion or the 50 year suggestion then to determine the trend in the most recent period I’ll get 2 different numbers which will consist of the growth due to anthropogenic effects and noise in the measuring system for which nothing has been done to remove.
I then introduce analysis to split out say warming or cooling effects from anthropogenic/Black carbon aerosols changes since the introduction of the clean air acts etc which I’ve seen suggested could account for 70%+ of recent Arctic temperature increases ie within both the 30 and 50 year timeframes.
When I do this I’ll see something approximating to a residual trend of anthropic CO2 driven warming something between 0.2 and 1.3 deg C per Century depending on whether the overall aerosol effect is 70% or 0%. Is this an unreasonable result? How long to wait before we can tell where reality was in this range?
How long before Monkton will be reporting an uptick similar to his current down tick basing it on a rolling 7 years?