I noticed this tweet by Tamsin Edwards this morning, advertising for applicants for a PhD to study the possible collapse of the West Antarctic Ice Sheet.
Quite a few people took exception to the seemingly inherent alarmist message attached to the study, in particular the use of the word ‘collapse’.
If you read through the blurb, it’s hard not to get the impression that those people who would be most likely to apply to study for this PhD under the supervision of Tamsin and her colleagues would already be fairly convinced that a collapse of the WAIS at some point in the future was more probable than not due to man-made climate change. This in itself is rather worrying. Indeed, I wonder in fact whether somebody who applied to study for this PhD and who openly made it obvious that they questioned ‘catastrophic’ AGW and in particular the likelihood of a future WAIS collapse would be offered a position on the team. But maybe I’m not being very generous to Tamsin and her colleagues there, though perhaps my cynicism might be more justified with regard to the OU and the project funding board. Who knows.
But anyway, what really caught my eye was this paragraph:
“The project will run during the same period as the Ice Sheet Modelling Intercomparison Project (ISMIP6) which will inform the Intergovernmental Panel onClimate Change Sixth Assessment Report for policy makers. Results on how BISICLES behaves under climate change and modelling uncertainties will be fed into ISMIP6 and the IPCC report, providing key evidence [my emphasis] for predicting future sea level rise.”
So basically, model simulations of WAIS collapse (or not) will provide ‘key evidence’ for the IPCC’s 6th Assessment Report. I questioned Tamsin on this and she seemed to think that it was quite normal that a quantitative risk assessment generated via computer models was the equivalent of evidence. Call me old fashioned, call me out of touch, but I’m just not very comfortable with this; most especially I am not comfortable with computer model outputs generated under various hypothetical climate change scenarios being elevated to the status of key evidence in AR6.
The dictionary definition of ‘evidence’:
“the available body of facts or information indicating whether a belief or proposition is true or valid.”
We can dismiss ‘body of facts’ out of hand, because there is none, barring perhaps the initial conditions applied to the model runs. So we are left with ‘information’ which, in IPCC climate science at least, can now consist exclusively of computer generated quantitative risk assessments, whereupon plain old ‘evidence’ becomes “key evidence”.
Forgive me again for being old fashioned and behind the times, but key evidence to me would be, in this case, direct observations of accelerated ice mass loss from WAIS – and there doesn’t appear to be a lot of that type of evidence around; in fact NASA recently threw a spanner in the works by claiming that WAIS was gaining ice mass.
Lastly, I should point out that I am not having a go at Tamsin here because, among the ‘climate change convinced’, she has at least made an effort to reach out to climate change sceptics and communicate civilly – and she hasn’t blocked me!
Climate Scepticism 
By strange coincidence, Prof. Curry has just published a post on her blog which relates quite closely to this post.
https://judithcurry.com/2016/04/28/expert-judgement-and-uncertainty-quantification-for-climate-changeon-a-likelihood-and-prior-distribution-but-it-does-not-mean-that-the-result-of-the-learning-is-valid-validation-ensues-when-posterio/
It is based on a study by Oppenheimer et al which talks of the need to formalize model-based uncertainty inputs to the IPCC, using a study of WAIS collapse as an example of this need. It talks of the need to unify formally unify expert judgement with numerical modeling in order to arrive at a more robust and independent assessment of future climate change risk.
“When it comes to climate change, the procedure by which experts assess the accuracy of models projecting potentially ruinous outcomes for the planet and society is surprisingly informal. – Michael Oppenheimer”
“Stepping back from probabilistic inversion to the general problem of uncertainty quantification, we end by suggesting a few signposts pointing towards an informative approach.
First, uncertainty quantification should have a component that is model independent. All models are idealizations and so all models are wrong. An uncertainty quantification that is conditional on the truth of a model or model form is insufficient.
Second, the method should be widely applicable in a transparent and consistent manner. As already discussed, several approaches to uncertainty quantification have been proposed in the climate context but fall short in their generalizability or clarity.
Third, the outcomes should be falsifiable. Scientific theories can never be strictly verified, but to be scientific they must be falsifiable. Whether theories succumb to crucial experiments or expire under a ‘degenerating problem shift’, the principle of falsifiability remains a point of departure.”
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More obsessing about the meaning of words. If one wants to predict ice sheet evolution, a model of how ice behaves, the physical environment including the grounding line and the movements of ocean currents around the continent is necessary. Nothing else cuts it. The result of modeling is the all the evidence there is, so it is ‘key’. You may think ‘evidence’ is the wrong word, but really, who cares? Find a better word in the thesaurus.
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It’s most unfortunate that Tamsin has chosen to follow the yellow brick road which I had first observed in the immortal phrasing of now-former IPCC-nik (currently engaging his “passion for politics” as BC’s sole Green Party Member of the Legislative Assembly), Andrew <climate change is a barrage of intergalactic ballistic missiles> Weaver.
Weaver – a CMIP honcho – long ago declared that the output of climate models is “evidence”. How disappointing that Tamsin seems to be following in Weaver’s “revisionizing” footsteps.
As an aside, I can’t help wondering if Weaver’s $50,000 (CDN) award (thanks to an utterly clueless newbie judge) against Canada’s National Post might have contributed to setting the precedent ball rolling for the ludicrous Shukla-style shakedowns we are now seeing in the US.
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Yeah, who cares Raff, it’s just a word after all. I mean, the CMIP5 multi-model mean is key evidence that we’re all going to hell in a handcart marked ‘Thermageddon via Exhalated Anthro Carbon – No No Stops in Between’. On a more mundane level, let’s scrap Crown Court ‘evidence’ and replace it with models which predict an accused’s likelihood of committing said crime.
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Could we have a map? Not all of us are experts in the geography of Antarctica. I believe the area in question accounts for 2% of the continent, with all sorts of poorly understood things going on.
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Surely measurement is what constitutes evidence. Computer modelling can only ever support measurements. Even excellent hindcasts cannot guarantee an excellent forecast.
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Geoff, I believe they are only predicting high melt rates in the Amundsen Sea Embayment up to 2100. After that – but only in certain circumstances – the melt rate increases significantly across the wider Antarctic area. Don’t ask me where the Amundsen Sea Embayment is!
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Geoff @ 7.43pm
West Antarctica is much more than 2% of the total area. I think that it is the Anatarctic Penninsula that is 2% of the area. This small bit – actually larger in area than the UK or about the size of France – has had considerable warming in the last three decades or so.
The area is quite small. More relevantly for sea level rise it only West Antarctica only has about 8.5% of total Antarctica ice. See Don Easterbrook’s article at Climate Depot – and the accompanying map.
The interesting thing is why climate researchers into global warming should be concentrating on a very small proportion of the total ice sheet, and not on East Antarctica. Easterbrook gives the explanations of the instability of the West Antarctica ice sheet.
http://www.climatedepot.com/2014/12/09/geologist-dr-don-easterbrook-the-west-antarctic-ice-sheet-is-not-collapsing-the-retreat-of-these-small-glaciers-is-not-caused-by-global-warming/
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Jaime
Thank you for the article. I quite agree that defining the terms used is important to understanding. Try defining the term “climatology” or “climate science” (Wikipedia) and you will find most the so-called “climate scientists” are making pronouncements well outside their area of competency.
In terms of evidence, modelling of climate change – or consequent ice sheet melting – will always be very weak circumstantial evidence, unless it is demonstrated to have a high degree of accuracy over the known range. Even then there is a problem. The really nasty impacts of global warming are allegedly due to tipping points. That is when the underlying relationships breakdown. In terms of modelling, you have discontinuous functions. If this is the case, then no matter how accurate the model is over the known data range (and climate models tend to have a huge range) if tipping points exist well beyond the known range (e.g. above 3 degrees of global warming when actual warming is less than 1 degree) then a predicted tipping point might be indistinguishable from the models falling apart as assumed empirical relationships cease to provide coherence.
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That’s very true Manic, to which I guess the alarmists might respond:
“You have two choices: either it’s bad or, because of non-linear responses which we can’t model, it’s very bad.”
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That’s how I see it. Empirical evidence in my book is key evidence. The output from numerical models is at best corollary evidence. Of course, Raff maintains that the computer generated output is ‘all we’ve got’; thus, this necessitates elevating computer-generated ‘data’ to the former status of empirical data – no matter that they are very different because ‘evidence’ is just a word whose meaning is very flexible, flexible enough to accommodate the requirements of predictive climate science.
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Sorry, above comment in reply to Richard.
https://cliscep.com/2016/04/28/when-did-quantitative-risk-assessment-become-key-evidence/#comment-3377
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Further to my comment of 28 Apr 16 at 8:32 pm (in moderation due to having a link and a graphic from ClimateDepot), an interesting point is why those studying global warming should be concentrating on the melting ice in West Antarctica, when East Antarctica has ten times the pack ice and over 70% of the global ice caps. But the proportions of estimated ice melt are quite different. Shepard et al. 2012 (which provided the basis for the ice melt estimates in the IPCC AR5 WG1) have the following estimates of ice change for Antarctica to the period 1992-2011 in Gt/year
Penninsula -20
East +14
West -65
Total -71
For the period 2005-2010
Penninsula -36
East +58
West -102
Total -81
So 90% of Antarctica is gaining ice, and 10% losing ice. On the face of it, the evidence is hardly suggestive that the net ice loss is due to global warming, against the alternative of local factors being the cause of ice loss.
Also, these numbers are vast. A gigatonne of water is a cubic kilometre or about the water in Lake Windermere (England’s largest lake). 71 gt is about nine times the volume of Loch Ness, which has successfully hidden a family of dinosaurs for thousands of years. 🙂
But in terms of sea level rise, it takes about 360 Gt of ice to raise global sea levels by 1mm. So, 20 years of Antarctic ice melting at 71 gt/year has raised sea levels by nearly 4mm. Or 71 gt of ice loss is the equivalent of annually slicing off 5-6mm of ice from the ice pack. At that rate, it will be all gone in just half a million years. With a bit of acceleration, it could be all gone in just two or three inter-glacials.
Shepard et al. 2012. A Reconciled Estimate of Ice-Sheet Mass Balance, Science 338, 1183 (2012); DOI: 10.1126/science.1228102
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I think models are extremely useful for learning about various aspects of climate, but they aren’t evidence. They do, however, give us an indication about what could happen in the future, and this is important to take into account when making decisions about climate change.
It’s important to remember what AR4 said about this:
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Excuse me, I had heard somewhere that that was from AR4, but it’s actually from the TAR. Though models have progressed a lot since then, I think that quote still holds validity today.
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Jaime, as you say the definitiom of the word on my Mac is “the available body of facts or information indicating whether a belief or proposition is true or valid”. If you dislike the use of the word ‘evidence’, what word would you use for the only available body of facts or information indicating whether the WAIS will collapse.
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“If you dislike the use of the word ‘evidence’, what word would you use for the only available body of facts or information indicating whether the WAIS will collapse.”
It’s like this Raff. If the only info you have doesn’t conform to the standards required by the word ‘evidence’, do you widen the definition of the English word ‘evidence’ to incorporate quantitative risk analysis or do you refrain from using the word evidence? It’s not a question of what alternative word or phrase I would like. That’s not the issue, though I am sure there are plenty of more suitable alternatives which could be plucked from the rich tapestry of the English language.
Like I said earlier, if the only information available with regard to an accused’s guilt or innocence of a crime was a computer generated risk assessment of how likely they were to commit the crime, would you expect the judge in a Crown Court to allow that information to be submitted as key evidence in the trial? Hopefully not! So you see it’s not just the word, it’s the principle. Do we water down the stringent requirements of ‘evidence’ so that computer model output in climate science can pass muster or do we insist on maintaining the higher bar traditionally associated with the definition of this word? I opt for the latter.
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Dr Tamsin Edwards left particle physics behind to go into climate science. One of her mentors was, I think, this self-important fellow from the Department of Geography at Bristol, whose YouTubed lecture on climate begins with ‘this lecture, I would argue, is incredibly important, really important for you’, with many more ‘incredibly‘s to follow – oh, if only he respected the literal meaning of that word! When I was young, I too might have been swayed by him – I was after all taken in by Ehrlich’s doom-mongering in the early 1970s. Now, I regard such people as scoundrels or buffoons, missing some gene that gives adults some sense of restraint when it comes to raising dire alarms.
Perhaps one day we shall have Departments of Catastrophism in our universities. Some might say we already have them under other names using terms such as ‘climate’, ‘environment’, or ‘sustainability’. The participants will be experts at seeking out possible events of great import such as huge earthquakes, mighty meteors, tidal waves, galloping ice sheets, tipping climates, and no end of bio- or chem-linked ones. Their skills will be in conjuring up vivid imagery using words, computer models, and even artists to show just how awful things could be. For them, this will be ‘evidence’, as long as ‘evidence-based policy making’, and ‘evidence-based grant awarding’ remain in vogue (under threat as they are from ‘policy-based evidence-making’ and ‘grant-based evidence-making’ tending to become more widely suspected).
More appropriate words than ‘evidence’ for them to use include ‘conjecture’, and, for their computer models, ‘illustrations’ – as in ‘programmer’s impression’.
Clive James has their number:
The imminent catastrophe goes on
Not showing many signs of happening.
The ice at the North Pole that should be gone
By now, is awkwardly still lingering,
Maybe one day we shall also have Departments of Taking the Piss out of Departments of Catastrophism. That would be a grand thing, would it not? I offer Clive’s poem as potential evidence for it coming to pass.
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I will simply highlight the quote that Gavin Schmidt uses, which is actually from Knutson & Tuleya
Call the information whatever you like, but until such time as observations of the future become available, you either have models, or you have nothing.
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Ken,
“Call the information whatever you like, but until such time as observations of the future become available, you either have models, or you have nothing.”
That’s the whole point; scientists should not be calling this information whatever they like – and what the IPCC scientific establishment appears to ‘like’ in this respect is ‘evidence’, even ‘key evidence’. I say call it what it is, not what it is not, because the average person will expect ‘evidence’ – especially scientific evidence – to have rather more clout than computer-generated projections amounting to quantitative risk analysis.
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John,
“Now, I regard such people as scoundrels or buffoons, missing some gene that gives adults some sense of restraint when it comes to raising dire alarms.”
Of course, it may be the case that there is a gene for ‘catastrophism’ which is ‘switched on’ in some people, but not in others . . . . gene therapy for catastrophists?
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Jaime,
Whether you like it or not, most scientists regard information from models as a form of evidence. You don’t have to like this and you’re free to argue against it, but that’s how it is. Maybe you think the general public is not bright enough to understand that projections of the future cannot be associated with observations and have to be associated with some kind of modelling. I happen to disagree. I suspect most members of the public understand that observations of the future are not available at this time.
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Congrats to Jaime for being selected as “Best of blogs” at GWPF!
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Thanks Paul and thank you GWPF.
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Perhaps climate models should be called “Music of the spheres.” Or is that copyright infringement?
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Jaime, do yourself and us a favour and search online for something like “computer simulations used as trial evidence”. Or ask a lawyer, there are some who bat for your side, Robin Guenier for example.
Here is an example that discusses “substantive evidence” (as opposed to “demonstrative evidence”) provided by simulation:
“In contrast, substantive evidence is evidence “adduced for the purpose of proving a fact in issue, as opposed to evidence given for the purpose of discrediting a witness, or of corroborating his testimony.” An example is a computer simulation or reconstruction of an accident where scientific and other factual data is entered into a computer that processes the data and generates a visual image of how the accident must have occurred. The results of a simulation are dependent on the application of scientific principles and mathematical calculations, and are treated by the courts like other scientific tests that require proof of the scientific principles and data before it is admitted.”
So it can clearly be ‘evidence’ if it reaches a suitable standard. From this you should conclude that you need to assess the merits of the computer modeling, not bitch about vocabulary. But the latter is obviously easier than the former and so will doubtless remain popular among skeptics.
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“In brief, we have the new paradigm where simulation and programs have replaced theory and observation, where government largely determines the nature of scientific activity, and where the primary role of professional societies is the lobbying of the government for special advantage.” (Lindzen quote)
If you like to eat carrots, and the government controls the carrot market, you won’t be eating carrots unless you follow the government’s edicts.
Evidence = observations/data
Evidence = models/simulations
Evidence = predictions/crystal balls
Evidence = consensus/propaganda
Evidence = lawyer talk
“It depends on what the meaning of the word ‘is’ is.” (Bill Clinton quote)
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Dave L, your timely quote from Lindzen helps explain this section of the advert for programmer-illustrators for the collapse of West Antarctica:
I bet they will. Some students might wonder if they are being set up. Others may see it as part of their duty.
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When Did Quantitative Risk Assessment Become “Key Evidence”?
When it’s all that they have? 😉
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“Jaime, do yourself and us a favour and search online for something like “computer simulations used as trial evidence . . . . you need to assess the merits of the computer modeling, not bitch about vocabulary.”
Wow, Raff, which of us is bitching? Obviously something has prompted you to take out your sharp, pointy little sword and start waving it about in my face.
A few points. You quote US law. I was talking about UK Courts, which are far less likely to rule computer simulations as admissible evidence, but no matter. In the States, computer simulations are allowable as ‘substantive evidence’ and they are treated as expert witness testimony.
Do you not think we have enough ‘expert witness testimony’ already in climate science!?
Additionally, the computer software must pass the Daubert standard for expert testimony and I’m not at all certain that the BISICLES adaptive mesh ice sheet model and the way it is employed piecemeal in this project would pass that standard.
“Simulations, on the other hand, are subject to the same scrutiny as more traditional scientific tests. Generally, a proponent of simulation evidence must establish that it is “based upon sufficient facts or data,” that the facts and data upon which it is based “are of a type reasonably relied upon by experts in the particular field,” that it is “the product of reliable
principles and methods,” and that the supporting expert witness “applied principles and methods reliably” when creating or using the simulation. . . . . . . Courts have recognized that computer-generated animations and simulations have the potential to mislead a jury by inaccurately portraying of events and to creating lasting impressions that override other testimony or evidence. See, Clark, 339 S.C. at 384, 529 S.E.2d at 536. In a society enthralled by cutting-edge technology, there is a real danger that juries will give undue weight to computer-generated evidence over less glamorous forms of evidence”
[http]://www.thefederation.org/document/7.Trial%20Use%20of%20Computer-Generated-Cellucci.pdf
“Since the software must be deemed an expert’s opinion, Daubert or
other expert opinion foundational requirements of the jurisdiction must be
satisfied in order to authenticate the software for use in producing an
admissible simulation.”
[http]://wllc.com/wp-content/uploads/2012/11/Admitting-Into-Evidence-Computer-Graphics-and-Simulations1.pdf
So Raff, as you are maintaining that computer simulations of Antarctic melt-down are admissible ‘evidence’ in the form of ‘expert witness testimony’, please demonstrate that the witness testimony involved here is of sufficient standard to be admissible as the ONLY evidence available and is valid enough to warrant the additional adjective of ‘key’ as input to IPCC AR6.
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Raff: “If you dislike the use of the word ‘evidence’, what word would you use for the only available body of facts or information indicating whether the WAIS will collapse.”
For simulations of this sort, the word I would use is ‘speculation’. If you’d like, you can qualify it as ‘informed speculation’.
Yes, Raff, some models/simulations are more grounded in more demonstrable facts. A simulation of an accident which uses principles/facts such as conservation of momentum, strength of steel, etc. can be quite accurate, and can be experimentally verified with observations of crash tests. To those models I would apply the word ‘evidence’.
But without verification from long-term observations or first principles, no. We’ve seen many models of e.g. Greenland glacier acceleration and ice loss in this century, based on guesses about mechanisms such as subglacial lubrication due to meltwater. Unsurprisingly, they’re not all consistent with each other. I think ‘informed speculation’ is about the right balance of what is known vs. what is guessed at.
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You quote US law. I was talking about UK Courts,…
I don’t recall you mentioning courts or legality and I don’t have the patience to re-read your rather fatuous argument to check. But clearly there is precedent in the use of models as evidence, one which side of the ocean makes no difference.
Give it up Jaime, your fox is shot. Any more and you just embarrass yourself.
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“Give it up Jaime, your fox is shot. Any more and you just embarrass yourself.”
Gee, you shot my fox. I guess I’ll just have to soldier on without Reynard and risk embarrassing myself in that case Raff.
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“If you dislike the use of the word ‘evidence’, what word would you use for the only available body of facts or information indicating whether the WAIS will collapse.”
Obviously the term to use is a “wild-arse guess”. Givben the state of climate science, anything generated by a model could just as easily be pulled out of someone’s arse.
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Raff found some grown-ups somewhere using simulation as evidence, so that’s it all settled as far as he is concerned. Tally-ho!
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Here is a grown-up finding real evidence which clashes somewhat with the computer simulated key evidence.
http://www.newsmax.com/LarryBell/Obama-Antarctic-Climate-Change/2014/05/19/id/572105/
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I never actually argued that there was not a precedent of using computer simulations in a court of law, but because Raff didn’t have the “patience to re-read [my] rather fatuous argument to check” he assumed I did and went on to shoot my poor fox by demonstrating that, in certain circumstances, computer simulations were admissible as ‘substantive evidence’ in a court of law. What I actually said was:
“Like I said earlier, if the only information available with regard to an accused’s guilt or innocence of a crime was a computer generated risk assessment of how likely they were to commit the crime, would you expect the judge in a Crown Court to allow that information to be submitted as key evidence in the trial? Hopefully not!”
If you’re going to nit-pick Raff, do make sure your nit-picking can’t be un-nitpicked.
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As one of the people who picked up on the ‘collapse’ word: Tamsin’s project is climate alarmism pure and simple. Not specifically the project but the general notion of WAIS collapse has its roots sunk deep as a member in the retinue of tipping point catastrophism that underpins much of climate alarmism. In this zone, the tipping point itself is firmly on the grounds of conjecture, but, once it is assumed, calculations of ‘uncertainties’ becomes possible. Suddenly you are sticking numbers and probabilities on things that never passed more basic scrutiny.
It’s like mathematically calculating the odds of being shot by an Australian ‘denier’, to great precision, after hearing the story of his recently-acquired hunting license at a dinner party.
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Um…has anyone ever considered the possibility that someone might actually cause the thing to collapse…on purpose?
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…and Then There’s Physics “Call the information whatever you like, but until such time as observations of the future become available, you either have models, or you have nothing.”
Try putting the word ‘unvalidated’, ‘speculative’, even ‘useless’ in front of ‘models’, and reconsider what you said. Since when did Hobson’s Choice become evidence?
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Shub,
According to NASA 2 years ago, the tipping point for various glaciers in the Amundsen Sea embayment has already been reached and grounding line retreat in this area is now ‘unstoppable’. Tamsin’s project appears to be an attempt to work out the finer details of this ‘unstoppable’ collapse, to pin down more precisely the timescales of this collapse under various climate change/emissions scenarios. More speculative and widespread WAIS collapse is reserved for post 2100 and is much less grounded in recent observations.
“Using two decades of ERS-1/2 data, we document a continuous and rapid retreat of the grounding lines of Pine Island, Thwaites, Haynes, Smith, and Kohler glaciers, which drain a large sector of West Antarctica on a retrograde, submarine bed, a configuration deemed unstable by ice sheet numerical models [e.g., Favier et al., 2014; Katz and Worster, 2010; Parizek et al., 2013] unless normal and tangential ice shelf buttressing could
increase significantly [Gudmundsson, 2013], which is unlikely. The retreat is proceeding along fast-flowing, accelerating sectors that are thinning, become bound to reach floatation and unground from the bed. We find no major bed obstacle upstream of the 2011 grounding lines that would prevent further retreat of the grounding lines farther south. We conclude that this sector of West Antarctica is undergoing a marine ice sheet instability that will significantly contribute to sea level rise in decades to centuries to come.”
http://onlinelibrary.wiley.com/doi/10.1002/2014GL060140/pdf
The devil is in the detail though. Thwaites, Pine Island etc. glaciers are melting due to warmer waters undercutting their bases. There is an assumption that these warmer currents are caused at least partly by AGW and therefore the melting will continue as long as global warming continues. But of course, there is no real quantification of how much AGW has contributed to these warmer waters vs. natural changes. There seems to be no consideration given at all to the possibility that warm water forcing of ice melt in the AS embayment might reduce at some point or even reverse. In the NASA paper quoted above, this would allow “normal and tangential ice shelf buttressing” to “increase significantly” and thus slow or halt the ‘inevitable’ collapse. The ice sheet models assume these ‘inevitable’ initial conditions, just projecting them out further in time under various warming scenarios but critically it seems they do not incorporate any reliable models of global oceanic circulation/heat transfer/redistribution, which is vital for quantifying the degree of warm water forcing in the West Antarctic region in the decades and centuries to come.
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Consider the structure of knowledge on the glacier shelves. There are glaciers draining into the sea, their tongues sticking out into water. In the 1980s – eons ago – the germ of the idea is born: ‘if these ice chunks break off and go floating away suddenly, that would be bad’. The data collection, the research, the modeling – follows riding on the back of the attractive notion of such collapse.
It is not as if a careful analysis of data lead to the hypothesis. The hypothesis is intuited – ice slipping on rock, warm water, lubrication, slippage, breakage – the mind can grasp simple sequence. That does not mean the real physics of these glaciers is the same. Maybe it is as simple, or maybe it isn’t, how does one know?
‘Oh, it’s hanging off an edge, at some point it will break. Let’s find the when.’ – say scientists. Where in scientific intuition is there allowed for a sheet of ice to a hanging off like that, to begin with?
In Amazon research there was a popular hypothesis of Amazonian dieback. At a particular point the evapotranspirative stress experienced by high canopy trees would tip large stands over, wiping them out, and the cycle would viciously repeat and render the whole Amazon into grassland. Again, a de novo hypothesis.
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Maybe the collapse of the Larson B ice sheet was the ‘evidence’ that got people worked-up. There for 10k years and then gone in a flash. But I’m sure in skeptic-speak that isn’t really evidence of anything that might happen to the Ross sheet etc.
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“Maybe the collapse of the Larson B ice sheet was the ‘evidence’ that got people worked-up. ”
Zzzz.
“This downward, inland slope was theorized decades ago, but has been confirmed and mapped in detail in recent years by airborne campaigns such as…”
How much value do you place in a dusty hypothesis from the 1960s? Knowledge is forever and timeless, but hypothesis are a product of their day and age, reflective of the culture of the time.
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In addition to the Easterbrook paper linked by Manicbeancounter above, there is even a more recent paper out identifying (actually measuring) geothermal heat production beneath the West Antarctic Ice Sheet.
http://news.ucsc.edu/2015/07/antarctic-heating.html
One must be careful and watch the pea under the thimble. Could we be devising models to implicate Climate Change, a.k.a. Global Warming caused by humans, but confusing the ‘science’ with Climate Change, a.k.a. Surface Warming caused by sub-terrestrial demons?
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RAFF at 1.50pm brings up the break-up of the Larson B ice shelf, which collapsed in 2002. Sir Nicholas Stern made a big thing about it in the introduction to his report in 2006. A chunk of ice shelf 3250 km2 and about 220m deep broke off. It if had been above sea level the ice would have raised global sea levels by almost 2mm. Only it made no difference. It was meant to be a sign of things to come, but nothing has happened on that scale since. It might seem huge, but it is equivalent to 0.025% of the area of Antarctica and less than 0.0025% of the total ice mass.
As evidence of much bigger ice shelf collapses elsewhere in Antarctica due to global warming it is useless. The Larsen ice shelves are at the Northern end of the Antarctic Peninsula, covering about 2% of the total area of the frozen continent. It has experienced warming many times the global average, unlike East Antarctica (90% of the area), where warming has been below the global average. The top of the Larsen ice shelf is one of the few tiny parts of Antarctica North of the Antarctic Circle, so one would expect changes in average temperature to have a much bigger effect on ice break-up than elsewhere.
https://en.wikipedia.org/wiki/Larsen_Ice_Shelf
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ATTP 29 Apr 16 at 10:02 am says
So we have to accept the complex computer models that do not fit well with the past, and only verified by people who believe in their efficacy, until they are proved wrong by the evidence. Then the only people allowed to produce and assess the evidence will are those who believe in the climate castrophism, and have a science-type PhD.
Maybe we should apply this to pharmacology. It would save a lot of time and money if we let the expert scientists who develop new drugs use their own test methods and analysis of the test results before release. After all, they have done all the research, so should be the leading experts on the subject. Then if people who took the drugs complained that they did not work, or bits started dropping off, the only people who be allowed to evaluate the evidence were people with a sciencey-type Phd who believed that the drugs were the greatest thing evah.
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No, you can do whatever you like. All I said was that observations of the future are not available at this time, therefore you either have some form of models, or nothing.
Again, no. Why would you think this? Anyone can produce and assess the evidence.
Assuming I understand your inference, if we did apply this to climatology, what other planet would like to live on while we follow this strategy?
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Just admit defeat that your astrophysics, astrobiology, climatology etc are irreproducible, non-experimental, observational sciences that should be preserved in vinegar in museums, ie, academic departments in universities, and not be allowed near the levers of power.
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aTTP: “All I said was that observations of the future are not available at this time, therefore you either have some form of models, or nothing.”
This does strike me as a particularly inane thing to say anyway, coming originally from Gavin Schmidt I believe.
On the assumption that observations of the future will probably never be available, all we will ever have are observations of the past and present – which form a body of empirical data or ‘proper evidence’. We can use this empirical data and models to project possible near future scenarios, with varying degrees of accuracy and success, just like the weathermen do plus numerous engineers and technicians etc. The difference is, they are constantly testing the accuracy of their models against observations of what does actually happen vs. what they predicted would happen. This is never going to be an option for the long range climate change forecast models and ice physics models. Essentially, their future ‘catastrophic’ projections are unfalsifiable and their shorter term projections which we might like to rely upon as the benchmark of their accuracy, even if they do turn out to be ‘wrong’ are argued by climate scientists to be ‘still within the range of expectations’!
So this ‘key evidence’ of future sea level rises ‘to be expected’ from melting Antarctic glaciers – which feeds into IPCC assessment reports and forms the basis of far-reaching policy decisions – is essentially intangible, non-verifiable and unfalsifiable.
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Jaime,
Depends what you mean by “inane”. If you mean “obviously true”, then yes.
Well, yes, this is kind of the point.
Indeed, as long as you use a model, as you seem to indicate.
Oh no, how could they? Oh, hold on, this is kind of how science works.
Never? You seem very certain. I guess complete ignorance is preferable?
Not true. We can wait and see what actually happens.
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..AND THEN THERE’S PHYSICS: “Call the information whatever you like, but until such time as observations of the future become available, you either have models, or you have nothing.”
So we have precisely nothing, in that case.
Thank God you are engaged in some totally worthless fantasy-based field where your prognostications can have no effect on the real world, not in something critical such as aeronautical engineering – or even wheelbarrow design!
Tell us Ricey, would you let your family travel on an airplane that had been designed by the likes of Gavin, Zeke and Mosh?
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ATTP 30 Apr 16 at 7:46 pm says
Assuming I understand your inference, you accept the a priori truths of the climate models despite the distinctive features of the models over extrapolations from recent trends – climate apocalypse – have not been corroborated by the short term evidence. In fact when we had an exchange on my blog last year you utterly failed to provide a single example of predictive successes by the climate community. I predict you cannot, based on my belief that if there were a predictive success thousands of climate
propagandistspublic relations experts would have seized upon such a chance achievement to justify their existence.Now suppose that contrary to the real world evidence, the climate models correctly prophesy doom. The preferred solution is to reduce global greenhouse gas emissions. Yet all the proposals on the table if fully enacted (a tall assumption) would make very little difference to global emissions by 2100. Every projection that says emissions forecasts emissions will be lower in 2100 is by splicing fanciful model projections onto politician’s promises. The evidence is from the UNFCCC, though they did not admit to it.
So there are therefore two possible scenarios.
The far more likely one, from actual evidence, is that climate catastrophism is false, and we in Britain are being subjected to useless policies promoted by a bunch of dogmatists with science Phds who neither distinguish the real world from a priori beliefs or between climatology and public policy. So we (the current generation in Britain) end up with high energy bills and loss of jobs and the subversion of democracy for totally unnecessary, regressive and ineffective policies.
Or a miracle happens and climate castrophism comes about. In Britain we will not be celebrating, because useless policies imposed by previous generations will have made the nation poorer than if they had done nothing, so they are less able to adapt to the impacts, and are less able to alleviate the suffering in the poorer nations.
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In evaluating evidence on controversial subjects, I believe it is best to draw upon other areas. One such area is what the criminal courts aim to achieve in Britain.
What I believe they try to achieve is incontrovertible factual evidence, and reject baseless opinion and prejudice. There is also an imbalance in the sides. The onus is on the prosecution to demonstrate their case beyond reasonable doubt. The defence only need show that there is reasonable doubt in the case. In this context how would climate models fit in? Any predictions about the future would be a matter of opinion, and normally be rejected. But a predictive model that had a perfect track record would might pass. But it could be argued that the models are being used for situations well outside the known data range on which the models are calibrated, so past predictive successes are unrelated to the predictions made. A predictive model that only had a 50% success rate would not be accepted, even if the prediction was within the known data range that the model was calibrated upon. A predictive model that could not point to a single predictive success in the short term, would be rejected out of hand when it claimed competency in scenarios well outside any known data range. I have tried in vain tried to find a single short-term predictive success of the climate community, let alone of the climate models. I challenged the resident Physics Troll last year. Given that this ultimate self-appoimted expert in everything related to climate (including politics, economics and morals) spurned the challenge, I can only assume that the narrower expert competency of the climate models is a complete and utter fiction. In a criminal court for expert testimony to be admissible the onus is on the expert to prove their expertise. Genuine climatologists like Tasmin Edwards should take up this challenge.
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Manic,
This is a rather odd thing to say. I can’t really remember your challenge, but it would seem pretty hard to take it up when you delete almost all my comments on your site. It’s also hard to see the point when I’m clearly dealing with someone who thinks that infering something about climate models based on what I’ve done is a reasonable thing to do.
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Ken,
“Depends what you mean by “inane”. If you mean “obviously true”, then yes.”
I mean what the word means: ‘Empty, insubstantial, lacking significance’.
The rest of your comment is somewhat inane – you aren’t picking up the gauntlet of nitpicking where Raff left off are you?
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Further to ATTP’s comment at 7.14am
In the link I gave at 12:39 am I have not deleted any of his comments on that thread, despite them being rude, evasive and derogatory.
ATTP has failed to disprove my assumption (despite being very knowledgeable of the field) that the …. expert competency of the climate models is a complete and utter fiction. He evades it, despite being having considerable knowledge of the field. Until such time, the crazy predictions of climate models should be considered by any reasonable person at a lower level than the prophesies of Nostradamus.
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Manic,
You can draw whatever conclusions you like. If you really want me to discuss this with you, you’re going to have to behave far more honestly and decently than you have so far. However, I don’t particularly care; you’re the one who seems to regard this discussion as worth having. I don’t. Some random person on the internet who wants to believe that somehow how I respond to their challenge can be used to infer things about climate models is neither here nor there to me. If anything I’m amazed that someone who seems to regard themselves as some kind of intellectual can think that this is a reasonable inference. Your ignorance, or lack thereof, is your problem, not mine.
Pot, kettle.
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“However, I don’t particularly care.”
Says the Sks kid who bans people on his blog and comes desperately to discuss things with the same people here.
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“you either have models, or you have nothing.”
That sums it all up pretty well. And it’s not enough. The consensus studies, the tipping point studies, they’re all alternatives to having convincing evidence. Well Hollywood beat you to it and before that there were sci fi writers of all sorts. Even the authors of the Bible were essential science fictionalists. Taking what you could prove and giving it another dimention. We’re all getting bored of the End of the World signs. Each one gets less and less reaction. If the best evidence you can come up with is computer generated catastrophe scenarios, you ‘have nothing’.
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ATTP’s evasions are clear. There is no empirical evidence to support the competency of climate models. It is all based on the opinions of the believers, and evaluated by arbitrary rules to support those opinions. ATTP’s trolling record shows his response to those with other opinions. That is shut them down by diversions and inflammatory remarks.
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When ATTP signs off 01 May 16 at 8:59 am with the insult “Pot, kettle” he does so as a loser to stop further argument. If he had the strong argument he might quote Matthew 7:3-5:-
Leaving aside whether one endorses the Christianity, it has more content than “Pot, kettle” . In the partial sciences (which climatology could aspire to without the dogmatists) or the non-scientific subjects like political philosophy and history, it is important to compare and contrast arguments. To do so competently you are forced to understand another point of view. It may change your own views, but (in academic terms) comparisons force clarification and restatement of your existing position. So even those who pursue a perspective that turns out to be wrong can provide a greater contribution to the subject than the dogmatist who ends up on the right side but tries to shut down debate. But this rarely happens. Those who fail to recognize their won biases, and shut down others will end up failing to make any contribution.
To start properly understanding climatology in the current angry atmosphere there are a few basic contrasts that need to be borne in mind.
– Positive and normative
– Big and small
– High quality evidence and baseless opinion
– Relevant evidence and irrelevant
It is also worth defining the boundaries on the subject(s) under discussion. With climatology being able to put some basic physics together into a model does not mean that one has competency on data analysis, economics and public policy. I discussed these issues a while back.
https://manicbeancounter.com/2013/09/05/fundamentals-that-climate-science-ignores/
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