Bishop Hill Niceness at home and abroad
Dec 2, 2014 Blogs Climate: other Shub Niggurath is bemoaning the lack of venues in which there can be conversations across the lines of the climate debate.
Good discussions used to take place, on occasion, at WUWT or BH. There were brief periods when the old Collide-a-scape blog and Bart Verheggen’s site provided such moments. They are hard to come by now. Maybe the consensus and conspiracy poison spread mindlessly and artlessly throughout the blogs by certain people is to blame.
He's right of course. I have struggled long and hard to make BH the venue where that can happen, but it seems that a visit from, say Richard or Tamsin is guaranteed to get some people riled, with the result that moderation becomes a full-time occupation. I can't afford to spend that amount of time on it.
Still, it's interesting to see that from some people's perspective, the limited exchanges here at BH are something to aspire to. As Judy Curry explains in her retrospective post on climategate, the state of the climate debate, and in particular the recent furore over Tim Ball's posting at WUWT and the riposte by Richard and Tamsin.
...the 1100 comments at WUWT were absolutely vitriolic against Betts and Edwards. On twitter, the vitriolic comments were coming from the warm side, i.e. how stupid they were to post at WUWT...Well, it seems Betts and Edwards are trying to promote civility, something that the UK does pretty well. Presumably they thought that posting at WUWT would be like posting at BishopHill. NOT. Climate change and social media is mostly blood sport over in the US (and Australia and Canada), where the situation remains very polarized and polarizing.
So I guess things could be worse. But please, everyone, do try to keep the temperature down when a comment thread features someone you disagree with. Even if they refuse to admit they are wrong or refuse to engage with your arguments or misquote you. If you start a shouting match, few people will hang around to see how right you are.
Reader Comments (422)
the amusing Rabett says "It is amusing to note that models can be more accurate than observations"
but gives no examples....of course. Why would he? How could he?
Harry Pass field
In simpler terms. Two satellites measured the spectrum and intensities of longwave IR radiation leaving the atmosphere. The first did so in the early 1970s, the latter in the late 1990s.
CO2 absorbs radiation around wavenumber 600, 15micrometres wavelength. The amount of outward radiation in that region decreased with time.This was consistent with the reduction expected due to increased CO2 concentration over the thirty odd years between observations.
"Increases in greenhouse forcing inferred from the outgoing longwave radiation spectra of the Earth in 1970 and 1997" Harries et al 2000
Diogenes
Since Mann published his paper in 1998 another 70 odd proxy investigations have shown a similar pattern of temperature change over the last 1000 years. How does this repeated validation of his results constitute a "fuck-up"?
@diogenes
Again you presume to criticise highly technical papers without the necessary competence. All that a lay person can reasonably attempt is to report accurately on the current state of play, ie ideas which are supported by the set of published papers which have not yet been refuted. That is what scientific knowledge is - no more and no less.
I sometimes wonder why the obsession with Michael Mann. Even if we gave him and all his work up for you to burn in a wicker man, you do realise that doesn't get you anywhere, right? He may be the only climate scientist you have heard of but there are actually hundreds of thousands of researchers who work in a range of different disciplines related to climate change, who are attached to many different institutions, and who are located in many different countries across the globe. You can even cull 10% at random if you like. It would barely make a dent in the case for AGW.
Pages2K gives a good summary of where we are with hockey sticks. Now we have a whole hockey league. Mann's original paper actually stands up very well.
http://thinkprogress.org/climate/2013/07/08/2261531/most-comprehensive-paleoclimate-reconstruction-confirms-hockey-stick/
There, ATTP, looks like you had a thread going and a sceptic commenting on it and it's winding along without you banning him. It's possible (unless you already flew into a rage and banned him, in which case I apologize).
Bish: This is your blog. If you don't want rude comments made when Drs. Betts and Edwards attempt to communicate with their opponents, publicly ban (at least temporarily) commenters who make rational discussion impossible. Even if poor judgment on my part causes me to be banned (hopefully temporarily).
I'm usually grateful when Drs. Betts and Edwards provide some scientific sanity to technical discussions. However, IMO they made a horrible mistake with their WUWT post. Dr. Ball asserted that the Big Lie is a political strategy used by the supporters of the IPCC, supporters of the ACA, and by other political movements - most notoriously the Nazis. IMO, Dr. Ball didn't CALL supporters of the IPCC consensus Nazis nor did he imply that they were Nazis. Hitler's name is mentioned four times in his post; Gruber's (ACA, not a Nazi) twice. I do think, however, that Dr. Ball made a serious mistake by not clearly that he doesn't associate the consensus with the Nazi's other crimes. The 10:10 "No Pressure" video demonstrates that radical environmentalists do have something in common with the Nazis
Furthermore, Drs. Betts and Edwards made a tactical bringing Dr. Ball's post to my attention with their equally misleading post. As a lukewarm (ECS is likely 1.5-2.5 degC; 50+% warming anthropogenic), I had never bothered to consider whether the IPCC consensus told "Big Lies". Upon review, I find the case better than Dr. Ball presented. Possible "Big Lies" include:
1) The science is settled. ***
2) The range in output from GCMs represents uncertainty about future climate change, not the much wider likely range for ECS. ***
3) Mis-representations about the "97% consensus".
4) An Inconvenient Truth.
5) Blaming AGW for Every Extreme Weather Event.
6) Dr. Mann was cleared of misconduct by eight investigations, making it potentially libelous for me to express my opinion about those white-washes and his behavior.
The lamplighter puts his foot into it
Well other than the issue of how Christy and Spencer were claiming that the surface was cooling through the 1990s, and theory said no. but here is an interesting one that illustrates Eli's point that observation is often falsified by additional factors not taken into account (just like the MSU issue which turned out to be an artifact of satellite orbital decay)
That's how.
aTTP is a fan of censorship.
Noel Darlow doesn't like information subject to FOIA being made public.
aTTP thinks that a doubling of CO2 ( that is, from the accepted but possibly erroneous 280ppm) to 560ppm would lead to a 2K to 4K rise in temperatures. Where is the problem? What are the downsides to this? I live in NW Europe. Summers are OK, but winters are usually a trial. I would prefer at least 6K.
Less H2O locked up in ice? Oh dear! More available water has to be bad!
We live on about 3% of the planet. Sea levels up, we might have to think about moving into the remaining 97%.
Whilst the barney continues on how many climate scientists can fit on the head of a pin, this is the real world:
http://enenews.com/fukushima-engineer-theyre-covering-badly-groundwater-contaminated-scientist-measuring-higher-levels-japan-levels-california-already-exceed-expectations-will-keep-rising-years-tv-cleanup-be-li
http://enenews.com/officials-admitted-failure-fukushima-plant-giving-attempts-prevent-highly-contaminated-water-pouring-ocean-regulator-asks-all-trouble-months-govt-experts-worried-cement-barrier-going-crack-vi
http://enenews.com/official-fukushima-nightmare-invisible-blanket-death-covers-everything-la-times-fukushima-heart-defects-related-nuclear-crisis-former-expert-blasts-fukushima-report-warns-cancer-spike-video
Surely people bother with this issue here because they think that either -
1. CO2 emissions cause harm;
2. Policies to reduce CO2 emissions cause harm.
I'm with no 2. But what about the great elephant, not in the room, but in the Pacific Ocean?
Entropy
Just had a quick look at the Harries et al paper in Nature Letters. It's an admirable piece of work and a good attempt to glean as much data as possible from historic experiments. However, both sets of data are fraught with observation difficulties (not surprisingly) but I do think they might have just about have detected some signal that results from concentrations of CO2 in the atmosphere - which, of course, is the expected result. But then, there's also the observation that the entire emission spectrum in the visual range is lower in the later observations by just under 1%. I'm not sure this stacks-up in terms of the world's energy balance.We need a lot more results and analysis before we hang our hats on this letter, I feel.
Entropy
"Since Mann published his paper in 1998 another 70 odd proxy investigations have shown a similar pattern of temperature change over the last 1000 years."
I hope that's not the case because if so either the proxy models or historical records are wrong. They can't both be right because they tell a different story.
In The Netherlands we have succeeded in organising a pretty civilized climate dialogue between protagonists and antagonists of AGW on the climate blog of Paul Luttikhuis:
http://www.nrc.nl/klimaat/2014/11/13/wat-ons-bindt-of-juist-niet/
As far as I know this is without precedent in human history.
The discussion is moderated at arm's length by a former director scientific research of the Netherlands Royal Met Office.
As far as I know this is without precedent in the history of the universe.
Eli Rabett: you have quite baldly implicated that there is more evidence to be gained from models other than whether or not the assumptions made in building that model were correct. I have asked you for an example of that evidence, as I am genuinely interested, yet, like Raff before you, you have quite blatantly avoided (or evaded; I’m not sure which) answering. Please could you put me out of my misery and educate me further – I can find NO evidence that a model can provide other than the assumptions made in its construction were correct or not! You and others seem to insist that there is – so, what other evidence is there!?
Capell
There's not just CO2 in the system. There is water, methane, CFCs and pollution aerosols.
All of the above have increased, some of them as a feedback response to the increasing CO2. The overall result is a drop in OLR across the spectrum.
OLR is about240 watts/metre^2. A 1% drop would be 2.4W/M^2.
All else being equal, at the IPCC's figure of 3.8W/C it would be expected to produce a warming effect of 2.4/3.8=0.63C.
GISS show the 1970 surface temperature as +0.04C and the 1998 peak as 0.61C. The actual surface warming between those years was 0.56C.
It is a back of the envelope calculation and a lot of modifying factors have been ignored, but the match is reasonable.
Radical Rodent
It might be worth saying what you mean by "evidence".
A recent commenter (Chandra?) was convinced that information about things that might happen in the future was 'evidence'. Despite the ordinary definition meaning information telling you that something happened or telling you about the state of something.
Dec 4, 2014 at 9:42 AM Capell
Since many (most?) of the other proxy reconstructions use data drawn from the same pool and done by colleagues with close professional connections it would be a bit surprising if they did not show similar patterns of temperature changes.
Capell
Both show temperatures near 14C around 1000AD and a slow decline into a Little Ice Age. This reversed at the start of the 1900s and we are now passing the MWP temperatures going back up.
I see no conflict.
Martin A
Different proxies come from dendrochronology, pollen analysis in peat bogs and lake sediments, forams in marine sediments, oxygen isotopes in ice cores, annual growth rings in coral, changes in snail growth patterns in archealogical digs; and many others.
These are not a common pool of data and their professional diveraity is enormous.
To imply a cospiracy between them is stretching credulity. It is more likely that the agreement between them is because they are measuring different aspects of a common reality and that the temperature pattern they deacribe is what actually happened.
TinyCO2 now warned and shooed away and given list of topics that are tolerable.
Since ATTP says he comments 'below the line' - whatever the crap that means - his requirements fundamentally boil down to (i) not being challenged excessively in the comments (ii) not be asked too many tough questions. This is owing to him being a physicist, which in his world means if he's understood something, the rest of the world can just take his word for it. It is hard maintaining a tough-guy image in front of a bunch of pussy cats.
Shub,
And here was me thinking you weren't a disingenuous [Mod : redacted]. All TinyCO2 was warned about was asking people personal questions like "if you care about the poor why aren't you giving them ALL your money?" Firstly that isn't a question anyone should be expected to answer and, secondly, it's moronic. Quite why some people expect others to take them seriously is beyond me.
As far as below the line is concerned, I simply mean that I interact with most - if not all - of my commenters. That happens to be true, whether you like it or not. I'm also happy to be challenged and regularly am. I'm also happy to answer questions and regularly do. Just because you don't like, or understand, the answers doesn't mean I didn't provide them. Also, there's only so many times I'm willing to explain the difference between a forcing and a feedback, or why most of the rise in atmospheric CO2 is anthropogenic, or why we think most of the warming since 1950 is us. Once I've tried a few times I tend to give up and since - unlike our host here - I'm unwilling to allow my site to become a place where people can spread misinformation, I then have to moderate the other commenter.
Entropy
The whole point about Mann's first proxy study (1998) was that it 'wiped out' both the historically recorded Medieval Warming Period and the historically recorded Little Ice Age. The impact that had was therefore stunning. So there was and is a huge conflict between the two.
Physics, there are now certain questions your blog commenters are should not "be expected to answer"? And this requirement is to be enforced by the summary deletion of the questions? Does seem awfully specific, no.
Could you point out an instance where you protected one of your skeptical commenters from meaningless questions by deleting comments?
Radical,
Ignoring that you may well be playing semantic games with the word "evidence", Eli is trying to tell you two things, both of which you should consider. Models are ubiquitous throughout the physical sciences. A bunch of measurements without a model are meaningless. You, typically, can't even turn a measurement into something meaningful without a model and even when you have a meaningful measurement you still need models in order for that measurement to tell you something about the system you're investigating.
Furthermore, if you mean "model" in the sense of modelling a system, then the only way you can determine how a system might evolve in the future is to use a model. We can't collect data from the future. Therefore it is clear that a model provides more information about how a system might evolve than not running a model at all (I would have thought that this was blindingly obvious). Of course, once your system has actually evolved, if your model result matches reality then you might be confident that your model is a good model. If not, then it's not a good model and you'll have to consider which of your assumptions are wrong or what you might have missed out from your model. That doesn't change that the only way to provide information about how a system might evolve in the future is to use a model. Whether or not you would call the model results evidence or not, doesn't really matter. Models provide more information, whether you like it or not.
Shub,
His question was not deleted. I have no interest in trawling through my blog to find an example of what you want but Rachel moderation is remarkably fair. Unless I'm mistaken, the only moderation that took place in the most recent thread was due to something said by someone who you would probably regard as a "warmist".
Entropy
This continues to push the Harries paper beyong its credability, I feel.
Why are you quoting GISS for 1998, when the study had ended a year previously? GISS for 1997 (the date of the later observations) reports an anomally of 0.46, giving a study period rise of 0.42 C. The Harries study overestimates this by 50 %. In the circumstances of the measurement, perhaps a good result, but possibly, also, serendipity.
capella
We have records for the cooling during the LIA in CET. They are locallised for England, but consistent with the worldwide cooling trend observed by Mann and others in the proxies. There are no measured records for the MWP, just anecdotal descriptions.
BH won't accept any links from me at the moment. I'll try to give you numbers laterlater.
Capella
I am a little surprised that my rough calculation got within an order of magnitude, let alone a factor of two. I won't quibble about which year to use.
My understanding of a model is that it will show you that the conclusions and assumptions you have made on the basis of your observations are correct. Let us take a simple example: seeing a bird fly tells you that objects that are heavier than air can fly. You saw the bird jump up and spread its wing, then flew: you follow suit, leap up and spread your arms – to fall flat on your face. Your first model is wrong; more data is required. A bird has feathers, so you stick feathers to your arm, leap up, and fall flat. Your second model is wrong. Continue for a few more years, until the Wright brothers make a model that gets what you desire, then continue refining the model – perhaps even making it a mathematical model in a computer. Note: none of the models tell you anything other than whether or not the conclusions and assumptions made from the data from your observations were correct (i.e. that worked; that didn’t) , yet you have advanced from flying a kite to hypersonic air travel.
Radical,
Let me try and explain the first part of what I said in a bit more detail first. Let's imagine you want to measure temperature. You develop a device that responds to temperature (Mercury thermometer, for example). Your initial measurement isn't temperature, it's the height of Mercury in your thermometer. To get to temperature you need some model of how height of Mercury relates to temperature. This is true for virtually any measurement you make. To take this one step further, once you have your data (temperature), what does it tell you? Well, nothing really. To use your data to understand the system you are investigating, you need something understanding of the system you're investigating. In other words, you typically need some kind of model. Data by itself is typically of no value. Data with some kind of model, however, can allow you to investigate a system.
What you're assuming here is too simple. You're ignoring that during the process you describe you could use your model to determine if it were possible to build something out of metal that could fly. Something with wings. You use Bernoulli's principle to determine what kind of lift you might get for various wing shapes and use that to determine what kind of plane you could build. At this stage you have assumptions and you have a model that tells you a possible design for a metal object that could fly. So, you know more than you did before (information) but you don't know, for certain, if the model results are correct. However, you certainly know more than you would if you simply guessed (although, technically, an informed guess could be a model of sorts too). You build the plane to discover if the model results are correct or not (or somewhere inbetween, not quite right, but a start).
I guess I should make clear that I'm using the term "model" in the broadest possible sense. It's any calculation - or process - that allows you to determine something about a system be it converting an electrical current into a meaningful measurement, taking that measurement to then determine other properties of that system, or building a complex computer model that investigates how a system may respond to changes in certain properties. All of these things provide information of some kind and I have no issue with people regarding this information as a form of evidence.
RR
You could add that in the process of working through your models you have established certain rules (maybe Laws) which become the basis of Aerodynamics. You learn about lift and the ideal conditions for it and how to control flight aspect with aircraft design and the use of ailerons and other applications.
You also discover that once you have added something or subtracted something then you get a consistent result and where you don't it is because of some other, unrecognised, source of conflict within the system. After the best part of a couple of centuries you have, as you put it, gone from kite flying to hypersonics.
And it is only because you understand the immutable (as far as we know at the moment) laws of physics, including gravity, that you can put an object the size of a fridge on an object the size of your kitchen several million miles away after it has travelled more than a billion miles.
And all this because of the Laws.
Now try doing all that with a system that is inherently chaotic.
As ATTP says, "if your model result matches reality then you might be confident that your model is a good model. If not, then it's not a good model and you'll have to consider which of your assumptions are wrong or what you might have missed out from your model". What you've missed out is that while each component of the climate may well follow certain well-established laws (water freezes at 0C, for example - and even that is not wholly true) there is a virtually infinite number of these laws acting on each other at different time, in different places, and therefore with different results.
Trying to model climate is as bad as trying to knit fog. Probably worse.
The models do not match reality. They certainly provide information, reams and reams of the stuff. They equally certainly do not provide evidence of anything except the composite failure of the models to model reality.
Mike,
Well, we almost agree about something, which is progress of sorts. I'll simply add the following. You might only consider your model as having failed if you initially thought that it could actually model the system over the timescale you've considered. You've probably heard this argument before, so I'll leave it at that.
To imply a cospiracy between them is stretching credulity. Dec 4, 2014 at 11:31 AM Entropic man
I did not say there was a "cospiracy". And I did not intend to imply there was one.
But have you ever heard of Groupthink?
Or read Feynman on successive results from people repeating Millikan's experiment** ?
Recently you commented on your amazement that people pay attention to factors other than purely scientific argument in deciding what things are likely to be correct and which things are likely to be false. That is a fundamental human talent and not being able to do so is a kind of disability when it occurs.
Here is one view of the successive proxy results:
[Mann Hockey Stick 1998] [---------] [---------] ..... [---------] [Marcott Hockey Stick 2013]
The first and the last in this sequence are discredited. How do you think that reflects on the others? Why should anybody assign the least credibility to them?
___________________________________________________________________________________________
**
Entropic man
The historic evidence for the MWP extends to data such as Chinese produce market-returns, descriptions of Arctis landscapes, archeological evidence of crop growing during the period all of which firmly establishes the existence of the MWP. This record seemed to have been accepted by luminaries such as H H Lamb. An example of his understanding of the MWP can be found here:
http://blog.lib.umn.edu/stgeorge/geog5426/Lamb%20Palaeogeography%20Palaeoclimatology%20Palaeoecology%201965.pdf
(which will save any embarassment of quoting Soon and Baliunas and thus avoid the peer-review cosh).
Mann's 1998 nonsense seems to be largely ignored these days, and rightly so.
"I guess I should make clear that I'm using the term "model" in the broadest possible sense. It's any calculation - or process - that allows you to determine something about a system be it converting an electrical current into a meaningful measurement, taking that measurement to then determine other properties of that system, or building a complex computer model that investigates how a system may respond to changes in certain properties. All of these things provide information of some kind and I have no issue with people regarding this information as a form of evidence."
for a better view, add
"... provided the models used are validated by observations."
@Capell
Any evidence in support of a MWP - ie a globally syncronized, multi-decadal warming period in the middle ages - would have to be presented as a formal, detailed, technical argument by a person who is competent to do so. All that non-competent people can reasonably do on an internet blog is to accurately report the existing body of knowledge ie there is nothing to show a globally syncronized, multi-decadal warming period in the middle ages.
Can't just make stuff up. It is kind of quaint though, like coming across an old, red telephone box in a remote highland village, to find a corner of the internet where people are still talking about the MWP.
not banned,
No.
How convincing - and so well argued.
Capella
You will be familiar with this ensemble of proxy data compiled by Marcott et al.
Note the decline in temperature from 5000BP. There is then an upturn around 2000BP and a thousand year plateau which probably corresponds with your idea of a MWP. The temperatures then decline into the LIA. Around 150 years ago the temperatures then stabilise and begin to rise again.
Again, I see no conflict with your concept of stable and reasonably mild temperatures followed by prolonged cooling and then warming.
I'm unconvinced that there are any number of words that could convince you. One seemed as good as any other number :-)
Thank you, Mike. I was trying to keep the example simple, hence I leapt straight from sticking feathers to your arm to the Wright brothers; but fell back onto kites, with the implication that a lot of other information had also been gleaned from these models. Along the way, a whole load of new information will have been discovered, but, no matter how complex your models become, ALL the evidence that they can provide is whether or not your conclusions and assumptions so far are correct. Can you use something other than feathers? Does the size of the wing matter? Does the shape of the wing matter (both in plan view and cross-section)? Does the shape of the fuselage matter? Is a tail-fin necessary? (Barnes Wallis showed that it isn’t; but, we still have tail-fins. Odd.) Even – is the scale on the meters correct (you mark the point where your water sample freezes, and mark where is boils, then divide the space into an acceptable number of figures)? All these can ONLY be discovered by trial and error (based on educated guesses, hopefully) – which is the purpose of education; being educated (particularly in science) gives you the knowledge of the failed and successful models created throughout history. Each and every model should give you more information, but the information given you is merely whether you are right or not. It is strange, but others are stating in their posts that this is correct, even though they then go on to claim that it isn’t – there is more evidence being gained, but are unable to specify quite what evidence.
Radical,
I think you're using the word "evidence" in very precise and definite manner and in a way that might not be the same as the way everyone else would use it. Given that language is simply a means of communicating maybe we can at least agree that models provide "information" even if you're unwilling to accept that that "information" could be described by the word "evidence". I don't really mind since the only thing I was trying to suggest is that if you develop, and run, a model to determine the future evolution of a system, you have more information than if you hadn't done so.
Let us take a hypothetical example of over-reliance on models: you create a computer model which proves that a cubical wing is the answer to flight. Your computer tells you that, if you fit a cubical wing to your aircraft, you will be able to fly twice as many passengers at twice the speed twice as far using half the fuel of a conventional aircraft. Now, you make physical models of this hypothetical aircraft: do you think that it will fly? Well, of course not – but, your computer tells you that it should! Which do you believe? At present, we are mixing with those who insist that the computers are right, and we should go ahead with building the aircraft – pronto! Would these same people be prepared to risk the lives of passengers on this hypothetical aircraft? (Sadly, I suspect the answer is, “Yes,” as none of the passengers will be the believers, or associated with the believers, and the believers will have absolved themselves of all responsibility, anyway.)
Radical,
I'm not sure that I get what you're implying by your example. I didn't say the information provided by models would be right, simply that it's information. In your example, your model will have some assumptions and some underlying physical laws. So, you would conclude - after running your model - that given these assumptions and laws, an aircraft with square wings should fly. That's information, but it is contingent on your assumptions and laws being correct. You build it. It doesn't fly. Okay, your model is wrong. Why? Assumption or law? Either way, you've learned something. Before you build the plane, you believe that it would fly if your assumptions and physical laws were correct. After building the plane, you now know that either your assumptions or physical laws (or both) are wrong. That's science. If you have repeated this experiment so many times that you now have a model that can correctly model almost any plane design, you have engineering. Unfortunately we only have one planet and we don't have a time machine, hence we cannot validate climate models in this way. That doesn't mean that they don't provide information, though.
Darlow,
I'm not sure why you accuse me of making things up, or presenting quaint evidence. And there's no need for a unified proof of a global effect since it would be quite sufficient for there to be demonstrations of coincident, localised warm periods. There are certainly many demonstrations of an Artic MWP, and also a coincident Chinese MWP. These demonstrations are far more convincing than your patronising red telephone boxes. Evidence from the southern hemisphere may be thinner in the historic record, but then this is also true of the proxy studies. That was the reason I cited the Lamb paper as it does attempt an analysis over a very wide area:
http://blog.lib.umn.edu/stgeorge/geog5426/Lamb%20Palaeogeography%20Palaeoclimatology%20Palaeoecology%201965.pdf
Now run along and patronise one of your servants.
Entropy Man
Yes, I see the MWP 'kick' in the Marcott data - with little difficulty!! Completely absent in both of Mann's papers of course, But I'm not that impressed. I need to see a higher blip. It's those reports of wine making in York that do it for me. But then, I'm being telephone-box quaint again.
"One seemed as good as any other number :-)"
Indeed - as fine a summary of the the state of climate modelling verification as one could wish for.
One of the favourite sources for definitions in English is the Oxford English Dictionary. Here is the on-line definition of the term “evidence” given by what most consider to be an august institution:
Please show me where I am deviating from that definition in my request for the evidence that is claimed is available from models. I do notice the deviation from the term “evidence”, to preferring the term “information”, as if that is in some way synonymous. So, please tell me what information, other than whether the original assumptions and suppositions were correct or not, can be gained, however far into the future the models might predict, and how valid is that information should reality be different from that given by the model?
Models do not necessarily provide any information at all, even if they "work" in the real world. For example (and this happens in economic modelling) you could create a model based on a series of variables whose outputs match what happens in the economy over a period of time. But, that doesn't automatically mean that the reasons you put into the model are the actual reasons. It could just mean that you have been lucky, or that your assumptions are pretty good proxies for things which are really driving events.
It is quite possible, in science and in everyday life, to do the right thing for the wrong reason.
Models should never be called "evidence."
Radical,
I'm not trying to argue about the definition of the word "evidence" (which I rather thought I'd made clear).
Your model tells you what might happen in the future if the underlying physical laws and assumptions are correct (or reasonable). That, in itself, is information. Of course, if all you want to know is whether or not these underlying assumptions and physical laws are correct, you can simply wait and find out. However, if your model suggests that - given these underlying assumptions and physical laws - something rather bad might happen before you have a chance to determine if they're correct, maybe you should consider that information and not simply dismiss it because you aren't absolutely certain that the model is correct.
@Capell
Which of us is patronising whom? The one who attempts to argue beyond their competence or the one who points this out?
There is no scientific controversy about the alleged MWP. Even most climate science deniers gave up on that one long ago. It is not reasonable to make statements about matters of science which are not supported by our current scientific knowledge.
"it would be quite sufficient for there to be demonstrations of coincident, localised warm periods"
No it would not. If you are talking about global warming you have to show that the globe was warmer - not just a few cherry-picked regions.
Sandy turned left.
"Your model tells you what might happen in the future if the underlying physical laws and assumptions are correct (or reasonable). That, in itself, is information. Of course, if all you want to know is whether or not these underlying assumptions and physical laws are correct, you can simply wait and find out. However, if your model suggests that - given these underlying assumptions and physical laws - something rather bad might happen before you have a chance to determine if they're correct, maybe you should consider that information and not simply dismiss it because you aren't absolutely certain that the model is correct."
Ah, I've often thought it would have been good to have seen Feynman lecture live. But now I realise that the thing to have seen would be him stopped in his tracks by the intellectual prowess of the one the very subject is named after. How foolish all Feynman's solid and definite words would have looked when confronted with the evidence of the "mights", "ifs", "assumptions", "suggestions", "rather bads", "chances" and "maybes" of "climate science"!
https://www.youtube.com/watch?v=b240PGCMwV0