Bishop Hill Falsifiability in my lifetime
Jan 16, 2014 Climate: Models An article on the Nature website looks at the failure of global temperatures to rise in line with the climate models and finds a possible explanation in the Pacific Decadal Oscillation. I notice what may be the start of a new meme emerging:
...none of the climate simulations carried out for the IPCC produced this particular hiatus at this particular time. That has led sceptics — and some scientists — to the controversial conclusion that the models might be overestimating the effect of greenhouse gases, and that future warming might not be as strong as is feared. Others say that this conclusion goes against the long-term temperature trends, as well as palaeoclimate data that are used to extend the temperature record far into the past. And many researchers caution against evaluating models on the basis of a relatively short-term blip in the climate. “If you are interested in global climate change, your main focus ought to be on timescales of 50 to 100 years,” says Susan Solomon, a climate scientist at the Massachusetts Institute of Technology in Cambridge.
The idea that the predictions of climate models are only good over periods this long seems to represent a considerable upping of the ante, but it's one that I have heard elsewhere in recent days - if I remember correctly it was also mentioned by David Kennedy in his evidence to the Energy and Climate Change Committee. In the past, the community has stood by a period of 30 years (at least when it suited them), but it may well be that the public start to realise that the models have been running hot over periods of several decades, the climate modelling community has been forced to extend the limits.
100 years should ensure that all concerned make it to retirement.
Reader Comments (202)
NeilC
I presume that by natural variation you mean the PDO.
If you want to use the PDO you have a problem. The graph in the Nature article shows that temperatures warm during the "warm" phase and stagnate during the "cold" phase. Since each warm peak is hotter than the one before, there is a long term warming trend.
I ascribe this to cAGW. What other mechanism would you suggest?
Jan 16, 2014 at 5:33 PM Entropic man
Making stuff up without evidence one way or the other but which sound as if it supports the point you want to make has a precise technical term*.
A BS assertion does not require to be responded to other than, perhaps, to point out that it is what it is.
Occasionally, in the past, you have raised interesting or challenging points. Why not wait until you actually have something to say rather than making stuff up just because you think it sounds good?
*BS.
One suggestion is “stall”. What are some others?
Freeze?
Martin A
Did you look at the graph?
I suspect you went straight into BS mode yourself without even a glance.
The Champagne Left will never be satisfied with only 100y.
No, the offspring and the offspring of the offspring need to be secured as well.
Anything else would be unfaiaiaiaiar
Copyright "laws" (an ironic reference to justice) go 75y but urgently need to be extended because many
trustafarians on the Left need to be further secured as well.
Negative increase?
Here is an interesting point: the AGWists say that they want to “save the lives” of future generations (some with the idea of killing many of today’s generation to that effect); many also say that humans are the problem, and removal of the species is the answer. I might not be very bright, but isn’t there a conflict in these two views?
I'm struck by the contrast in the "falsifiability situation" between climate science and my job, medical device development.
Climate modeling claims that there is a high likelihood of climate catastrophe sometime in the next 50-100 years.
When a doctor puts one of our devices in a patient, we claim that there is a low likelihood of catastrophic failure during the patient's lifetime (which, by interesting coincidence, could be 50-100 years!). There are thousands of such patients.
So every day that dawns is a new opportunity (thousands of them, actually) for me to be proven wrong, but I can't be proven right in my lifetime.
Climate predictions of catastrophe could come true tomorrow, but can't be proven wrong in the modelers' lifetimes.
Am I in the wrong business?
“The observations indicate to me that the models are probably running hot, that the impact is about half of what they are showing."
This came from a recent Steve McIntyre interview.
http://www.nbr.co.nz/article/too-much-hot-air-about-global-warming-says-researcher-rv-1
Those saying that there has been no warming are being contradicted by your own statitistics buff. He clearly thinks that warming has slowed, not stopped
If we believe Susan Solomon, we must wait another 25 years or so before we can make useful inferences from the models. Then why have climate scientists presented model results in the past and why do they do so today?
Why is it that climate scientists always speak in oracular sound bites? "Beware the model period that is 20, 35, or anything less than 50." "Beware the model whose solstices number less than 100."
Does anyone actually believe that we will using the same models in 20 years?
Another awful article from the Holtzbrinck press (Nature).
I don't see any merits for Trneberth, he is very late with that admssion. Just because Nature is even later does not make him look like a genius.
No mention, that oceans must have contributed about half of the warming in 1976-1998, if ocean are now able to stop it.
No mention that this means climate models run to hot by aboput a factor of 2.
No mention that this halfed sensitivity would be an excellent match with new sensitivity studies.
Entropic man (Jan 16, 2014 at 5:33 PM) said "If you want to use the PDO you have a problem. The graph in the Nature article shows that temperatures warm during the "warm" phase and stagnate during the "cold" phase. Since each warm peak is hotter than the one before, there is a long term warming trend.
I ascribe this to cAGW. What other mechanism would you suggest?"
Given that the warming trend appears to have started prior to 1920 (http://woodfortrees.org/plot/hadcrut4gl), this would suggest that your cAGW mechanism began to take effect before the significant rise in atmospheric CO2 concentration.
One suggestion is “stall”. What are some others?
Jan 16, 2014 at 11:22 AM Douglas J. Keenan
Depression
When your prediction of the future is wrong, your understanding of the past is wrong too.
What have you done with the real Entropic Man? That 8:05 PM comment is ludicrous.
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The increase in CO2 began in the latter 19th century and the rise in temperature from 1910. It probably depends on how you define "significant rise in CO2 concentration".
Over the period in question it was about 0.001%/decade. I calculate the equivalent temperature rise would be (5.35*ln(290/280)) / 4 = 0.05C/decade in the early years
Em, the higher the climate sensitivity, the colder it would now be without the effect of AnthroGHGs.
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KLM
Not a joke. You people don't even pay attention to your own experts.
Em, the higher the climate sensitivity, the colder it would now be without the effect of AnthroGHGs.
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Jan 16, 2014 at 9:28 PM | Unregistered Commenterkim
Could you expand on that. I'm not clear what point you are making.
Would you mind posting the cite of the Susan Soloman quote that leads this post? I want to pass it on so someone with whom I periodically debate this topic over a glass or three of Calif. cabernet. He is an academic and insists on a paper trail. This and Fred Colbourne's comment Jan 16, 2014 at 12:00 PM are "money quotes."
RayG -
There's a link to the Nature article in the first line of the post. Here it is again.
I can't state it any more plainly Em. You better hope natural variability dominates.
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We could try this, Em. Pick a climate sensitivity that frightens you and then calculate how cold it would now be without the effect of AnthroGHGs. With a high sensitivity we would be below the lows of the entire Holocene; with a low sensitivity, natural variability has bounced us off the bottom.
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The climate models resemble the Soviet Union tractor factories which not only did not make any tractors, but didn't exist at all.
They were convenient fictions invented to placate the higher-ups who wanted, for political reasons, a particular narrative to prevail.
kim
Going by the nunbers, our own CO2 production bounced us off the bottom.
Harold W, thank you. I missed it on my first reading of the Nature article. I wonder if the editor of the article did the same as this is certainly problematic coming as it does from a stalwart of the alarmist brigade. :-)
Well, then Em, there aren't enough fossil fuels to keep us off the bottom.
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Entropic man (Jan 16, 2014 at 9:18 PM) said "The increase in CO2 began in the latter 19th century and the rise in temperature from 1910. It probably depends on how you define "significant rise in CO2 concentration"."
Yes, that's the thing about 'evidence' for CAGW, its founded upon "definitions" that seem to change to fit the empirical data, or lack of it... which is the main point of this thread.
If anyone is confused by alarmist-speak (such as used by EM) - it's because they sneakily change the meanings of phrases in mid-argument and sometimes in mid-sentence:
For 'warming' they mean total warming but they pretend it means manmade warming. So they can say you have to be a 'denier' to say that warming is not increasing but ignore that this warming could be all natural and hence manmade warming would not then be increasing, which is the real argument.
Climate change has become shorthand for overall global warming (natural or not) but they pretend it means more extreme weather events and then use this switch to talk about climate change impacts, meaning short-term weather impacts including even cold weather, and ignore the measured zero impacts from long-term warming.
Climate sensitivity is usually assumed by everyone to mean sensitivity to CO2 but when a skeptic mentions the medieval warm period the alarmist then suggests that a large medieval warm period means higher sensitivity (hence worse) because they have cunningly switched from CO2 sensitivity to natural climate sensitivity.
Likewise skeptics criticize the 'models' meaning specifically the GCM's but arch-warmists will pretend it means any type of model in order to say that some models are ok, ignoring the fact that no GCM's are never ok.
This fooling themselves is made worse by flagrant abuse of the language such as:
'May get worse' instead of 'a 50/50 chance' or 'we don't know'. Evidence' instead of 'opinion'. 'Expert' rather than 'researcher', 'Increased energy in the atmosphere' meaning a paltry (and disputable) 4% increase in water vapour since the 70's., etc, etc.
Whether this is deliberate obfuscation for their perceived idea of greater good or merely fooling themselves depend on the person. Climate scientists (the shamens) mostly do the former while their cult followers do the latter.
Jan 17, 2014 at 8:48 AM | JamesG
Your summary is spot on! Entropic man is well named - the logical falicies, excuses and confusion keep on increasing ........
JamesG
Nice assessment.
And the obfuscation continues with that deadly phrase "since records began" when the records refer only to 0.00000000375% of the life of the earth or the weaselly "since [pick a scary date more than 100 years ago]" which most people don't realise means there was something as bad or worse then.
Entropic Man
Is this what's worrying you?
EM: "I ascribe this to cAGW. What other mechanism would you suggest?"
And so we go full circle. In order for this statement to have any value, or indeed, any real meaning, one would need to understand what the definition of catastrophic means in the context and whether the a has satisfactorily been proved - beyond doubt (in 'caGW'). There is no doubt that warming has taken place, and no one I know denies that. Indeed, it is accepted that cooling will/is take/taking place and this raises the question: if cooling starts to look as 'catastrophic' as warming, will the likes of EM look for a scape-goat for it in the same way as they have accepted the evil CO2 is responsible for warming?
Wow SandyS, that is a very interesting graph!
It very clearly demonstrates the utter ridiculousness of the position of people like Increasing-disorder-man, being scared of something that has already been this way for thousands of years, with great civilizations flourishing during or possibly even because of it...
HP 10:34
As I said previously, making stuff up without evidence one way or the other but which sound as if it supports the point you want to make has a precise technical term (BS). A BS assertion does not require to be responded to other than, perhaps, to point out that it is what it is.
One characteristic of the best bullshitters is that they do not even realise they are bullshitting.
Martin A: I'm rather glad I read your earlier post about EM and BS, so I like to think you were merely reminding me of that - and not accusing moi of such a trait. :-)
I would be more willing to accept that natural variation drove 20th century warming if you could supply evidence of the mechanisms involved and numbers to match.
Without such evidence, you ladies, gentlemen and others are the BS merchants.
SandyS
My tablet rejected your link. Superior BS detection, perhaps?
Entropic man (Jan 17, 2014 at 1:12 PM) said "Without such evidence, you ladies, gentlemen and others are the BS merchants."
Sorry EM, your line of reasoning is either poor or you really are posting here simply to antagonise people... just because I cannot explain 'consciousness' does not mean that I have to accept spiritualism.
Absence of evidence is not evidence of absence!
Em, we don't understand the millennial scale natural changes, but they are there.
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EM
I would be more willing to accept that natural variation
drovedid not drive 20th century warming if you could supply evidence of the mechanisms involved and numbers to match.As I have said repeatedly, in the absence of convincing evidence to the contrary we have to assume that natural activity drives climate as it has done for millennia.
The rather pathetic excuse that "we couldn't think of anything but CO2 to make our models work" is not a good enough reason especially since 1. the arbitrary figure assigned to pre-industrial CO2 levels has been challenged; 2. the date from which that arbitrary figure started to increase appears to be up for debate (you are now saying 'late 19th century' while others give various dates as early as mid-18th century); 3. we have managed to get modellers to start admitting that their models are not all that good with clouds, PDO, AMO, cosmic rays even though extracting this concession has been like drawing teeth; 4. CO2 concentrations lag temperature and not the other way round.
I repeat: it is not good enough to think up a bright idea, find a few factoids that happen to match and declare you have discovered the answer to everything and expect everyone else to grub around trying to disprove your assertion.
If you believe that is the way the world works let me interest you in an infallible racing system which I have mentioned on here before and which is based precisely on this principle. It hindcasts the last five years perfectly; it proves that following the winners of certain selected races next time they run will get you £100 to a £5 level stake over the course of a season. Yours for only £25 — or if we're talking global warming, £several billion!
Em, have you been thinking a little more about my 9:28 PM comment last night? That little point packs an awful punch. I came up with it while thinking about Richard Muller, of BEST, and his attribution to AnthroGHGs for all the warming since the Little Ice Age.
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SandyS ( & wijnand) - the GIS ice core Holocene temperature graph is excellent, but note that Lappi's data ended about 100 years ago (the work was done in the late 60s(?), and they can't use the last 50 years or so of ice becuase it has not firmed up enough to give reliable data). So to fairly compare Lappi's curve with Mann's hockeystick, you have to add another 0.7C rise onto the end of the uptick, to bring it up to present, e.g. http://snag.gy/tJ7z6.jpg.
Kim
If climate sensitivity were larger, 1880 would have been warmer, 2013 would have been warmer and the difference between them would have been larger.
Since this is self-evident I fail to understand your excitement.
Thanks, lapogus. That link worked. Looks just like Marcott et all.
"Absence of evidence is not evidence of absence!"
Jan 17, 2014 at 1:24 PM | Unregistered CommenterDave Salt
But that's the way to bet.
There is an absence of evidence that little green men landed on my lawn last night. Anyone claiming they did would bear the burden of proof.
There is a considerable literature on natural variation. The scientists who examined it when compiling AR5 concluded that natural variation accounted for less than half of the observed warming. This includes NAO, PDO, AO, solar cycles, Milankovich cycles etc.
If you wish to claim that natural variation explains all of the change, the burden of proof for the extra natural warming is yours.
It's up to them to prove their ridiculous theory. In case anyone forgot.
Esmiff
Agreed. Anyone claiming that natural variation is sufficient to explain the 0.8C warming we have observed must show where the energy came from.
Meh, you forget the conditional was without man's effect. The higher the sensitivity the lower the temp would have been in 1880 without the anthro effect, and so also for 2013. With all of the warming from the LIA attributed to man, then we would be testing the lows of the Holocene without man's effect, a time when 2/3rds of the population in some northern climes died out.
You better hope that natural variation has caused the bulk of the temperature rise since the LIA, because economically recoverable fossil fuels are limited. We haven't enough fossils to sustain a Holocene waiting for the Fat Lady to sing.
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By the way, we'll probably get around to figuring out where the energy for the rise came from, now that there is a new focus on natural variability. It's likely the same place as the energy changes which have caused the millenial scale natural changes in the past, and it's probably from the sun.
Ignore the millennial at your perennial.
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EM
now your inferior tablet can link with Lapogus' graph the question remains what exactly are you worried about and what do you think is attributable to man and what is not? How many previous warming events in our interglacial have similar upward gradients and how many end up at a greater temperature? Have you checked out all 13 interglacials (possibly more) in the 2.6 million years to confirm your conjecture that this is the worst ever and only attributable to man?
Entropic man (Jan 17, 2014 at 5:30 PM) said "If you wish to claim that natural variation explains all of the change, the burden of proof for the extra natural warming is yours."
I did not claim that natural variation explains all of the change, please do not imply that I did!
The simple fact is that there is currently insufficient evidence to give strong support to any one mechanism and that the smart way to bet is that it's a mixture of many... which probably includes some CO2 contribution but not nearly enough to justify the CAGW hypothesis.
I look forward to your rebuttal of Mike Jackson's points (Jan 17, 2014 at 1:41 PM).
I see Dr Judith Curry has just posted her statements to the recent Senate hearing...
http://judithcurry.com/2014/01/16/senate-epw-hearing-on-the-presidents-climate-action-plan/
It tends to support the views expressed by many in this thread... but probably not those of EM?