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Comments 36001 to 36050:

36001. DSL at 23:07 PM on 11 June 2014
       Ice picks: Five pieces of ice news revealing earth’s ice cover is in serious decline
       

       I imagine the paid opinion-shapers are picking up on the word "elevated" and turning it from a spatial reference into a temporal reference.  I don't have the stomach right now to go look.

36002. michael sweet at 22:31 PM on 11 June 2014
       Ice picks: Five pieces of ice news revealing earth’s ice cover is in serious decline
       

       This calculation was posted at RealClimate by Meow:

       "Alright, let’s do some basic physics. Let’s assume, for the sake of argument, geothermal flux of 200 mW/m^2 over the entire Thwaites catchment, and also that all of that heat goes into melting the overlying ice (as opposed to, say, heating it to the melting point). The Thwaites catchment has an area of ~189,000 km^2. Water ice has a heat of fusion of 333.55 kJ/kg. A 200 mW (=0.2 J/s) flux is 6.3 MJ/yr (0.2*3600*24*365). That flux will, thus, melt 18.9 kg of ice/yr. Since the flux is distributed over a m^2, the melt rate will be 18.9 kg/m^2/yr, or 3.6 Gt/yr for the entire catchment.

       The actual melt rate for the Thwaites, exclusive of calving, is ~70 Gt/yr (Depoorter et al, doi:10.1038/nature12567, http://www.staff.science.uu.nl/~lenae101/pubs/Depoorter2013.pdf , at Fig. 1)."

       So, even assuming a geothermal flux almost 2x that in Schroeder, and that all of it melts ice, geothermal flux contributes, at most, 3.6/70=5.1% of Thwaites’s meltwater, and probably much less"

       There are some other informed comments about this paper.  It appears that the estimated heat flux is 2-4 times higher than average in this area.  I remember having seen a calculation of the effects of a volcanic erruption in Antarctia several years ago (sorry no cite).  It also melted a km3 or 2 of ice, no big deal in the long run.  Keep in mind how big the basin is and how thick the ice is.

36003. MA Rodger at 21:50 PM on 11 June 2014
       Resources and links documenting Tol's 24 errors
       

       Towards the end of the post, the link to the "full list of 24 errors identified by the experts reviewers at ERL" also provides links to the Tol's paper as sent to ERL and a later draft. Although there will be changes in the paper evemtually published in Energy Policy, it is very helpful to understanding the nature of Tol (2014). I was not happy discussing a paper in so much detail when, bar the odd quote, it is entirely hidden behind a paywall.

       Now seeing the nature of the beast, I find it incredible. From its incompatible title to its strange list of Acknowledgements (a list that includes Dana Nuccitelli, "Willard" and in the draft version "wottsupwiththatblog.") I have to say, this is not a publishable paper.

       As far as the 24 errors are concerned, Tol may take an embattled win on one or more of them and a few would end up as score draws, but the majority of the criticisms of Tol (2014) seem well founded and also include fundamental problems for Tol (2014).

       But the most fundamental question for Tol is "What is Tol (2014) trying to say"?
       Tol (2014) is not a "re-analysis" because that would present an alternative to the 97% as its main finding. Ditto if this paper was mainly concerned with identifying errors within Cook et al (2013). If the thrust of the paper were the inadequacy of method, it would then be less bothered with the specific result - but a whole whole lot more bothered that Tol (2014) demonstrates on how to achieve an adequate method. Tol's paper is polemical but for no justifiable academic reason, and this is magnified by the content of the Abstract.

       But why end there. Tol goes well beyond the substance of his paper when he tells us that, although there is "very little reason to doubt that the consensus is indeed correct," for Cook et al (2013) "theirs is not a consensus on the causes of climate change." And anyway "consensus is irrelevant in science," and "has no academic value," because it "serves a political purpose, rather than a scientific one," at least in this case. Yet in this case, this particular consensus, "it is well-known" already and "it does not matter whether the exact number is 90% or 99.9%." And further, the alleged errors within Cook et al (2013) "may strengthen the belief that all is not well in climate research." So don't do this consensus enumerating stuff. Stick with the reviews of the literature itself. They already establish where science has got to on climate change."The IPCC fulfils this role."
       That, I fear, is all argument for argument's sake. It is not useful to man nor beast. But I do see in it the sort of argument that somebody in denial would likely come out with.

36004. scaddenp at 19:11 PM on 11 June 2014
       Ice picks: Five pieces of ice news revealing earth’s ice cover is in serious decline
       

       Context here might help. 200mW/m2 is 4x average flux, but flux through an active volcanic area (eg the Taupo Volcanic Zone) is around 700. Thwaites is high in places but not extreme.

36005. bratisla at 18:32 PM on 11 June 2014
       Ice picks: Five pieces of ice news revealing earth’s ice cover is in serious decline
       

       I did a quick search for any evidence of geothermal flux temporal change, to no avail. What is known is that, of course, geothermal flux increases a lot when a magma bubble goes closer to the surface and triggers dyke creation - it comes with seismic long period events and increased hydrothermal activity. And using geothermal heat reservoir to produce heat or electricity "depletes" them, creating a "cold" bubble that can be replenished over time (a loooong time)

        

       So, changes in geothermal flux are *possible*. Even on a 10 year timescale.

       BUT. I may be wrong, but I do not see any natural mechanism other than a volcanic system reactivating under the glacier ; such a system should be detectable by an increase of LP events recorded by seismic stations. Otherwise geothermal flux should be quite stable, and therefore can not explain the *increase* of calving speed.

       Nor can it explain the glacier front retreat. My 2 cents.

36006. scaddenp at 17:48 PM on 11 June 2014
       Ice picks: Five pieces of ice news revealing earth’s ice cover is in serious decline
       

       I agree it lubricate flow but moving back the grounding line? Alternative hypothesis - the observed warmer ocean is eroding the shelves and glacier ends. What seems most likely? Also consider that fluxes this high are very localized.

36007. Klapper at 15:53 PM on 11 June 2014
       Ice picks: Five pieces of ice news revealing earth’s ice cover is in serious decline
       

       @scaddenp #5:

       If geothermal flux was increasing it could contribute to basal melt, which would in turn lubricate and accelerate flow. So you could make an argument that increases in geothermal flux could trigger increases in caving rate.

36008. One Planet Only Forever at 14:49 PM on 11 June 2014
       Challenges in Constraining Climate Sensitivity: Should IPCC AR5’s Lower Bound Be Revised Upward?
       

       Though the discussion needs to move beyond global average surface temperature as the main metric I would prefer to clarify that a global average surface temperature trend based on following average surface temperatures of longer time periods (like a rolling 30 year average) can still be meaningful. A longer time period can reasonably average in the many signficant but randomly fluctuating factors that can affect the global average surface temperature. The 30 year average in the GISTemp data has continued to rise through the past 15 years at a rate of over 0.15 degrees per decade. However, a longer time average could lead the delayers to claim te need to wait 30 more years before deciding if anthing conclusive has been proven. That would not be helpful.

       SKS has presented other effective ways of showing the changes by including reasonable adjustments of global average surface temperature for the major variable influences.

       The greatest benefit from the continued pursuit of even better way of integrating all the factors will be the improved ability to forecast things like expected regional weather to improve crop performance by better matching planting with the expected regional weather during the growing season, or the improved forecasting of the potential for significant regional weather related emergencies.

       The more humanity is able to understand the way our amazing planet functions the easier it will be to develop a sustainable better future for all.

36009. WheelsOC at 14:00 PM on 11 June 2014
       Challenges in Constraining Climate Sensitivity: Should IPCC AR5’s Lower Bound Be Revised Upward?
       

       "Nature As An Ensemble Member, Not An Ensemble Mean"

       If this kind if thing were more widely known and understood, it might take some of the punch out of those "the models didn't predict the Pause!" posts that always swamp the comment threads of any news article about climate change.

       Of course, it also helps to understand the difference between a model projection and a climate/weather FORECAST. That's a slightly broader issue, into which the data/ensemble difference can figure neatly.

       Frankly I think the general public needs a simple primer on climate modeling, and why you can't just eyeball the typical ensemble mean graph and extract useful information without knowing how these things work. But this primer would have to be a mass-media, mainstream kind of thing that also reaches the audience demographics who need it most. We can't just trust to climate blogs and Youtube presentations to get the info where it needs to go, because self-selection is so very prevalent. Good luck getting Murdoch-owned networks to run such a segment.

36010. scaddenp at 13:56 PM on 11 June 2014
       Ice picks: Five pieces of ice news revealing earth’s ice cover is in serious decline
       

       Hmm. Those fluxes are quite high and they claim validation against ice drilling. I would expect volcanic fluxes to vary somewhat in time as well but to be highly localised. However, I dont think you could extend that to be the cause of rapid calving and ice-shelf loss.

36011. DSL at 13:20 PM on 11 June 2014
       Ice picks: Five pieces of ice news revealing earth’s ice cover is in serious decline
       

       I mean given what the report says it should be obvious that a time series on sub-glacial geothermal activity doesn't exist.  This is a potential start to such measurement, and it's an important indicator that such activity is significant, but no one associated with this study has anywhere claimed that flux under WAIS is increasing or decreasing on the scale of climate, so no claims of "this instead of that" can be made.

       If the WAIS is rapidly deteriorating, and the cause is increasing geothermal flux, what an remarkable event this is.  When was the last time any major Antarctic glacier rapidly deteriorated as a result of such flux?  Not in the last 1.5 million years, I'd wager.  

       That's not to dismiss the effect, of course.  Flux may be constant, but it still plays a critical role in helping along the decline of the WAIS.  This is quite bad news.

        

36012. wili at 12:59 PM on 11 June 2014
       Ice picks: Five pieces of ice news revealing earth’s ice cover is in serious decline
       

       So..."rather obvioustly"...nothing is obvious?

36013. DSL at 07:07 AM on 11 June 2014
       Ice picks: Five pieces of ice news revealing earth’s ice cover is in serious decline
       

       Rather obviously, the research says little about the trend in sub-glacial geothermal flux. Perhaps the trend has been negative over the last five hundred years.  Perhaps positive.  Perhaps the diminishing ice is allowing increased geothermal activity.  The paper is really about a new method of determining sub-glacial geothermal flux.

36014. wili at 05:27 AM on 11 June 2014
       Ice picks: Five pieces of ice news revealing earth’s ice cover is in serious decline
       

       Any chance you could also comment on this recent paper?: Dustin M. Schroeder, Donald D. Blankenship, Duncan A. Young, and Enrica Quartini, (2014), "Evidence for elevated and spatially variable geothermal flux beneath the West Antarctic Ice Sheet", PNAS, doi: 10.1073/pnas.1405184111

       http://www.pnas.org/content/early/2014/06/04/1405184111.abstract

       I'm already seeing denialists jumping all over it, claiming it shows that GW is not responsible for any of the melt in Antarctica.

36015. citizenschallenge at 02:26 AM on 11 June 2014
       Resources and links documenting Tol's 24 errors
       

       Good information.  For what it's worth, I've reposted this along with some comments.  :- )

       http://whatsupwiththatwatts.blogspot.com/2014/06/richard-tols-big-mistake-or-malicious.html

36016. Tom Curtis at 01:46 AM on 11 June 2014
       Richard Tol accidentally confirms the 97% global warming consensus
       

       Richard Tol has now published a response of sorts to the "24 errors".  I say of sorts in that he merely responds in a single line, often with fairly straightforward falsehoods.  As an example of the later, he responds to Error 22, ie, his claim that the trend in endorsements in Cook13 is due to a trend in composition by saying:

       "C14 do not dispute key claim: C13 mistook trend in composition for trend in endorsement."

       However, C14 explicitly state (and highlight in a side box) that:

       "Additionally, the compositional changes in the abstracts occur halfway through the survey period, but the consensus shift was observed in the first 25% of the period.  The shift in composition and the shift in consensus do not coincide, thus negating T14’s claim."

       So, the 24 Errors document explicitly rejects Tol's claim, providing clear cut evidence for that rejection.  I don't know whether Tol's straightforwardly false claim is a consequence of his reading no more of the document than section headings, or whether he does not care about the truth of the matter, and expects his supporters to care no more, so that a straight forward falsehood is all he needs.  As a response to criticism, however, it is simply not good enough.

36017. Tom Curtis at 23:09 PM on 10 June 2014
       Richard Tol accidentally confirms the 97% global warming consensus
       

       Meanwhile, returning to the actual topic, I have been running through the data and found a genuine error in Cook et al 2013.  Specifically, in Cook13 it is claimed that initially "... 33% of endorsement ratings disagreed".  In fact, a careful comparison of all first and second ratings shows that only 15.56% of first and second ratings for given papers disagreed.  I presume the authors determined that figure as I did, by determining the number of 2nd ratings that disagreed with first ratings (or vice versa) and doubled it to allow that a disagreement between a second rating and first rating is also a disagreement between first and second ratings but did not double the denominator to allow for the fact that there were twice as many abstracts if both ratings are considered.

       Given the detailed analysis of the paper performed by Tol, it is remarkable that he did not also check the initial disagreement rate and simply accepted the stated figure.  Regardless, with the correct figure, the "error rate" drops from his (incorrectly calculated) 18.5% to 7.6%.  That leads to an estimated final error rate of 1.43% (compared to Tol's 6.67%).  Applying that error rate using Tol's demonstrably faulty method then results in a corrected consensus rate of 96.5% (compared to Tol's 91.4%).

       So even if Tol's primary analysis were correct, rather than the absurdity it in fact is, his conclusions do not follow from the data he analyses.

36018. Composer99 at 23:02 PM on 10 June 2014
       Climate is chaotic and cannot be predicted
       

       nickels was also resorting to a genuine fallacy of argument from authority - on the sole basis of nickels' asserted PhD, we were supposed to take nickels' criticisms of climate modelling at their word.

       To which the response is, not going to happen.

36019. Tom Curtis at 22:54 PM on 10 June 2014
       Richard Tol accidentally confirms the 97% global warming consensus
       

       chriskoz @28, regardless of RobH's assertions, the article did in fact appear in the Australian, and the Australian is certainly published by one of the constituent bodies, ie, News Ltd.  Further, publication of this sort of biased, and poorly researched story on climate science is par for the course for the Australian and Grahame Lloyd.  Indeed, the Australian is so bad that Tim Lambert, prior to becoming unfortunately inactive, was up to number 83 in his series on "The Australian's war on science".  The Australian's treatment of climate science also features heavily in Robert Manne's astute criticism of that publication (very worth buying by any Australian citizen or student of the press).

36020. chriskoz at 21:49 PM on 10 June 2014
       Richard Tol accidentally confirms the 97% global warming consensus
       

       Tom@27,

       Thanks for your link to APC. Re your quotes about principles, they only apply to the constituent bodies of APC. Incidentally, I looked at APC complain page and found out this:

       The only major newspaper which is not published by a constituent body is The West Australian. [...] The Council may also consider complaints about material published by other publishers. But, unlike constituent bodies, those publishers are not under a legal obligation to cooperate with the Council or to publish any adjudication by it.

       Note the assertion by RobH@25:

       Although appearing in the West Australian, this item would never appear in the The Australian

       I don't read Australian so i'm not sure what's going on here but based on the above,it now appears obvious that this article by Graham Lloyd, the Sydney-based env editor, was deliberately placed in West Australian, so as to avoid the adjudication by APC.

       But that does not preclude anyone, like me and you from making a complain to the publisher itself. I remember having sent couple complains to newspapers like smh or HP about their climate science contents. In each time, the response was positive and the contents fixed. What makes you think that the Australian ignores the rulings of APC? Have you sent them any comments/complains in the past (like I did to smh) but were ignored?

36021. CBDunkerson at 21:29 PM on 10 June 2014
       President Obama gets serious on climate change
       

       Hi vrooomie.

       Yes, that's from the United Nations development goals site.

36022. Tom Curtis at 19:44 PM on 10 June 2014
       Richard Tol accidentally confirms the 97% global warming consensus
       

       chriskoz @26, The Australian does not need to pay attention to the blogosphere, but in principle they do need to adhere to the Press Council standards.  In particular, they need to ensure that their reporting satisfies the first standard:

       "General Principle 1: Accurate, fair and balanced reporting

       Publications should take reasonable steps to ensure reports are accurate, fair and balanced. They should not deliberately mislead or misinform readers either by omission or commission."

       At a minimum, balanced reporting would require at least contacting the lead author of the study criticized by Tol to get their take on the cricitisms.  Now either The Australian contacted John Cook, in which case they new of the flaws in Tol's work and chose not to mention them (in which case the story is neither accurate, nor fair, nor balanced); or they chose not to contact John Cook in which case their reporting is at minimum not balanced.

       I have been reading The Australian with a close eye to see if it now satisfies the next two principles:

       "General Principle 2: Correction of inaccuracy

       Where it is established that a serious inaccuracy has been published, a publication should promptly correct the error, giving the correction due prominence.

       General Principle 3: Publishing responses

       Where individuals or groups are a major focus of news reports or commentary, the publication should ensure fairness and balance in the original article. Failing that, it should provide a reasonable and swift opportunity for a balancing response in an appropriate section of the publication."

       So far neither have been complied with, and nor do I expect them to do so.  They have in the past ignored adverse rulings by the Press Council in order to push a denier line.  I see no reason why they would now improve their performance.

36023. chriskoz at 17:07 PM on 10 June 2014
       Richard Tol accidentally confirms the 97% global warming consensus
       

       RobH@25,

       The Australian's report, technically does not need to pay attention to the news in blogosphere, when it wants to report on verified, peer reviewed publications only. And that is the current state of C13 critique: Tol 2014 comment is an accepted, verified article; whereas all subsequent critiques of Tol 2014 are unverified rumours. In particular, Tol's critique herein, has been "accepted by Energy Policy but not yet published". When is it going to be published? Then, you'll be technically rightful in your statement that: "the Australian deliberately distorts news items".

        

36024. RobH at 15:30 PM on 10 June 2014
       Richard Tol accidentally confirms the 97% global warming consensus
       

       Despite the recent news on Tol's comments, the Weekend Australian 7/8 June went ahead with a news item "Doubts on climate consensus" quoting an earlier position by Tol as if the news did not exist. It appears that the Australian deliberately distorts news items on global warming issues.  The Australian, our "authoritative" national daily, appears to have a policy of negatively influencing decision makers on carbon mitigation strategies.  Such a stance supports deliberate misinformation put out by our prime minister - quoted this morning as stating that carbon trading schemes are being discarged internationally when in fact this is a direct denial of World Bank reporting the opposite that eight new carbon markets had opened last year.  Although appearing in the West Australian, this item would never appear in the The Australian . The Murdoch mob can only be regarded as basically evil, note their top brass facing criminal charges in the UK. 

36025. davidnewell at 12:04 PM on 10 June 2014
       Climate is chaotic and cannot be predicted
       

        (snip)

       Moderator Response:

       [PS] Please stop using Skeptical Science to advertize your website. Further attempts will be regarded as spam.

       [RH] Snipped content.

36026. wili at 11:19 AM on 10 June 2014
       New Video: Meltwater Pulse 2B
       

       Good points, chris (though I assume you meant "10 cubic kilometers in less than a month times three months of melting season" = about 30 Gt or 10%.

       But that's through one mechanism of ice loss from one location on a very large island. Does anyone have estimates of how much is generally lost these days through calving annually, versus surface melt>evaporation and surface melt> runoff, versus subshelf melt?

36027. John Hartz at 10:04 AM on 10 June 2014
       Climate is chaotic and cannot be predicted
       

       Nickels: Your comments have been deleted because they were not in conformance with the SkS Comments Policy.

       Please note that posting comments here at SkS is a privilege, not a right. This privilege can and will be rescinded if the posting individual continues to treat adherence to the Comments Policy as optional, rather than the mandatory condition of participating in this online forum.

       Moderating this site is a tiresome chore, particularly when commentators repeatedly submit offensive, off-topic posts or intentionally misleading comments and graphics or simply make things up. We really appreciate people's cooperation in abiding by the Comments Policy, which is largely responsible for the quality of this site.

       Finally, please understand that moderation policies are not open for discussion. If you find yourself incapable of abiding by these common set of rules that everyone else observes, then a change of venues is in the offing.

       Please take the time to review the policy and ensure future comments are in full compliance with it. Thanks for your understanding and compliance in this matter, as no further warnings shall be given.

        

       Moderator Response:

       [PS] And lest there be any misunderstanding about what was breached, then we have:

       - No cyberstalking.

       - No moderation complaints

       - No inflammatory tone.

       - No sloganeering.

       The threads are full of skeptics able to discuss the science without violating the commentary policy.

36028. chriskoz at 09:09 AM on 10 June 2014
       New Video: Meltwater Pulse 2B
       

       wili@2,

       To put that "10 cubic kilometers of ice in 3 months" into perspective: 10km³ = 10Gt. But the total Greenland melt rate is currently approaching 300Gt/y. So, depending on your point of view, either the reported melt is minor (some 10%) on the global scale, or the global scale is so big as to be unimaginable: dwarves even the "entire mountain range".

36029. Dikran Marsupial at 08:17 AM on 10 June 2014
       Climate is chaotic and cannot be predicted
       

       nickels. For your information, I am a moderator at SkS, but I didn't moderate any of your posts, not one.  I do not moderate any discussion in which I am taking part, and leave it to others, for obvious reasons.

36030. nickels at 07:42 AM on 10 June 2014
       Climate is chaotic and cannot be predicted
       

       <Snip>

       Moderator Response:

       [PS] Conformance with the  comments policy is not optional. It appears you have not bothered to read it. We delete comments that do not conform whether they are pro or anti on any argument. Got that? Take a deep breath, read the comments policy and continue the debate. Asking questions is not baiting - it is about about establishing a common ground. This site is concerned with scientific truth and is not a high school debating contest.

36031. Dikran Marsupial at 07:36 AM on 10 June 2014
       Climate is chaotic and cannot be predicted
       

       nickels, it isn't hostile if you stick to the comments policy and give straight answers to direct questions.

36032. vrooomie at 06:42 AM on 10 June 2014
       President Obama gets serious on climate change
       

       "Similarly, your claim that Americans would 'continue' emitting up to 20 t of CO2 per person per year even after these reductions is ridiculous given that U.S. emissions are lower than that now. U.S. per capita emissions peaked at 20 t for a single year back in 2000 and have fallen significantly since then."

        

       CBDunkerson, that's an interesting stat: Could you please provide a link for that? I'd appreciate it, and being able to add it to my anti-dismissive "quiver."

36033. Dikran Marsupial at 05:51 AM on 10 June 2014
       Climate is chaotic and cannot be predicted
       

       It is a shame that nickels' two posts above will be deleted as they show that he is deliberately trying to get his posts deleted, rather than trying to engage in scientific discussion.  I have no idea why people seem to find that a good use of their time, life is short, much better to spend it on something more productive.

       Note all I have done is to ask questions politely - note the response from nickels.

       Moderator Response:

       [JH] I sincerely believe that climate deniers are awarded a "merit badge" when they relinquish their privilege of posting on SkS comment threads.

36034. MA Rodger at 05:50 AM on 10 June 2014
       Climate is chaotic and cannot be predicted
       

       Dirkran Marsupial @93.

       I was being quite aggressive myself @92. I did catch the comment calling me but a single uncomplimentary name. It was referring me to look at Saari & Xi (1995) - Off to Infinity in Finite Time. Now the Newtonian n-body problem addressed by Saari & Xi (1995) is a fun mathematical construct but its applicability to the solar system (which has managed to remain ib situ for a few billion years without "going infinite") is something the authors fail to mention. They don't mention bumble bees either.

36035. Dikran Marsupial at 05:34 AM on 10 June 2014
       Climate is chaotic and cannot be predicted
       

       nickels, calling people names is not doing you any favours.  It is also likely to result in the mdoerators deleting your post [ah, I see that has already happened], so if you want to make a substantive point, make it politely.  Please read the comments policy and adhere to it.  We get a fair few visitors here who deliberately try and get themselved banned, so they can whine about it elsewhere.  That is not very mature behaviour, so please demonstrate that you are above that sort of thing.

       Moderator Response:

       [RH] Agreed. The only reason nickels is getting deleted is for violations of commenting policy. No problem with him presenting a dissenting position, it just has to be done in a way that conforms with policy.

36036. Dikran Marsupial at 05:26 AM on 10 June 2014
       Models are unreliable
       

       nickels wrote "I don't feel like having huge amounts of my tax dollars chasing other peoples 'common sense'."

       sorry, whether science is correct is not dependent on your views of taxation (the causal relation should lie in the other direction).

       "I have a PhD in mathatics."and "I challenge your science to study the Verification and Validation methods used commonly in engineering."

       I have a PhD in engineering; the methods used in climate models are used in computational fluid dynamics in a wide variety of engineering industries, for example aviation, motor racing, ship design.  All without mathematical proof of the nature that you are asking for.

36037. MA Rodger at 05:08 AM on 10 June 2014
       Climate is chaotic and cannot be predicted
       

       We appear to,have 2 nickels running down two different threads with the same arguments, this thread and the one here*.

       nickels @89.

       You tell us elsewhere* that you hold a PhD in Maths. You tell us here that "Mathematically it is my understanding that the entire solar system could actually go infiite." I find these two statements uncongruous, unless you are not being serious. It is akin to an aerodynamics engineer pronouncing that a bumble bee theoretically cannot fly.

       Indeed, apart from demanding/requesting a mathematical proof for the findings of climate models, your posts are entirely vacuous, a situation that is not compatable with your stated background.

       Of course it may be part of your nature that you present an aggressive posture here, but buddy I don't give a dime.

       (By the way, to call the structural calculations of a building's design a "proof" in the mathematical sense is very poor use of the english language.)

36038. Dikran Marsupial at 03:59 AM on 10 June 2014
       Climate is chaotic and cannot be predicted
       

       O.K., so nickels is rather impolite!

       My question regarding planetary orbits was not baiting.  It was an attempt to make a serious point.  I'm sure that most of us are happy with the idea that planetary orbits can be predicted, however we can't write down an equation for the solar system that gives the orbits of the planets, i.e. we can't have proof of their orbits, and we have to solve them numerically.  Does that mean planetary scientists are not rigorous?  No.  Does that mean that we should not accept their predictions of planetary orbits?  No, of course not.

       As Einstein said "" ... as far as the propositions of mathematics refer to reality, they are not certain; and as far as they are certain, they do not refer to reality.".  

36039. Tom Dayton at 03:57 AM on 10 June 2014
       Models are unreliable
       

       nickels, climate models have been validated (using the proper definition of validation, after reversing your definitions) empirically, as is explained thoroughly in the original post at the top of this comment thread.  (Be sure to read Intermediate tabbed pane, too, and the cited peer-reviewed publications.)  Your challenge to the "science" (sic) "to study the Verification and Validation methods used commonly in engineering" is odd, because climate modelers in fact do use V&V methods commonly used in engineering.  In contrast, you seem to believe erroneously that V&V in engineering relies heavily or even exclusively on mathematical proof. Your statement "You would get run out of engineering in a minute claiming that you think a building will stand because you ran a few models and everything looked good" is correct, but your implication that bridge designers instead use only mathematical proof to convince themselves that it will stand, is wildly wrong.

       My job largely is V&V of spacecraft software and some hardware and certainly their interaction, of both software used on the ground to monitor and control spacecraft, and software that runs on the spacecraft itself.  Mathematical proof is only a tiny portion of that V&V. 

       A good place to start learning about V&V of climate models is at Steve Easterbrook's blog Serendipity.  He has a good recent video of a TED talk (you should read the text surrounding that video on his blog), a short but good description of V&V, a short description of massive and thorough comparisons of the outputs of 24 climate models, an explanation of why some formal methods cannot be applied to climate models but Agile-like methods can, and especially relevant for you is his post Do Climate Models Need Independent Verification and Validation?  You would benefit from reading other posts of his that you can find by using his blog's Search field to look for "verification" or "validation."

       Also useful for you to read is Tamsin Edwards's series of four short blog posts the links to which are near the top of her post Possible Futures.

36040. Dikran Marsupial at 03:30 AM on 10 June 2014
       Climate is chaotic and cannot be predicted
       

       nickels,

       Firstly, I notice that you didn't answer my question.  Scientific discussion relies on both parties being interested in seeking the truth, and this in turn requires an honest attempt to give a direct answer to direct questions and an absence of evasion.

       I know plenty of mathematicians (I am married to one), and I don't know any that are so rigid that they would ignore any statement of something that was abundently obvious regarding the real world.  Very obvious things do turn out to be incorrect (actually rather rarely), but that does not mean that it is rational to ignore them.  Proofs turn out to be incorrect occasionally as well.

       "My literature request is sincere."

       my attempts to explain a truth of applied mathematics to you is equally sincere, it would help if you were to give direct answers to my questions.

36041. Tom Dayton at 03:22 AM on 10 June 2014
       Models are unreliable
       

       nickels, you have reversed the definitions of verification and validation.  That is suprising given your self-claimed expertise.

       Moderator Response:

       [JH] Nickels is already skating on the thin ice of sloganeering and his haughty attitude is duly noted. His future posts will be closely monitored for compliance with the SkS Comments Policy. 

36042. nickels at 03:21 AM on 10 June 2014
       Climate is chaotic and cannot be predicted
       

       @DM

       If there is one thing that my mathematical training has taught me, it is to ignore any statement like 'abudnantly obvious'.  Its a cultural different between mathematicians and climate guys.  Very obvious things turn out to be very wrong all too often.

       And I also am not into 'proof by extrapolation of argument', so I don't want to take the planet bait.  Mathematically it is my understanding that the entire solar system could actually go infiite.

       My literature request is sincere.  Stability of computing averages is actually possible to make a decent mathematical argument towards.  This is part of my mathematical background. 

       Which is why I have to produce literature requests whenever I talk to climate guys....

        

       Moderator Response:

       [JH] Your response to Dirkan's question about the pendulum is an artful dooge. Dikran also posed a legitimate question to you about planetary orbits. Your repsonse suggests that you are not here to engage in a civil conversation. We have little patience for concern trolling.

36043. jja at 03:19 AM on 10 June 2014
       New Video: Meltwater Pulse 2B
       

       It is clear now that the current IPCC sea level rise projections have significantly underestimated what will be.  What Rignot did not show was how continual warming and surface wind dynamics will further exacerbate the mass loss trend, though he alludes to it when mentioning the less-studied east Antarctic ice shelf. 
       
       These are all connected and feed back to each other, as does the PIOMAS analysis which projects total summer ice loss of Arctic sea ice within the next 20 years.  Sks has done a great job showing how the current IPCC models have overestimated arctic sea ice persistance by 30 years or more.
       
       While it is obscure, the loss of arctic sea ice will lead to a significant see-saw effect on WAIS mass loss rates, combine this with this recent tipping point analysis and the 30-year acceleration in permafrost methane release and our current Integrated Assessment Models have dramatically underestimated the social cost of carbon.

36044. Dikran Marsupial at 03:14 AM on 10 June 2014
       Climate is chaotic and cannot be predicted
       

       nickels, O.K., I am moderately surprised that you are unwilling to accept that the electromagnet will cause the double pendulum to be closer to the electromagnet on average than it would otherwise be, given that it is abundently obvious that this is true (consider the case as the magnetic field becomes very large).  However, at least your position is consistent.

       So, do you accept that we can predict planetary orbits?

36045. nickels at 03:11 AM on 10 June 2014
       Climate is chaotic and cannot be predicted
       

       @DM

       I would be happy to read a paper that has some proof along these lines (would actually be interested in literature in this area).

       Even if there isn't a proof, a numerical study with serious attempts at aposteriori error control would be interesting...

36046. Dikran Marsupial at 02:55 AM on 10 June 2014
       Climate is chaotic and cannot be predicted
       

       nickels, do you accept that the statistical properties of the double pendulum in a magnetic field are non-chaotic?

36047. nickels at 02:39 AM on 10 June 2014
       Climate is chaotic and cannot be predicted
       

       @DM

       Understood.  And I am certainly not saying climate models are wrong or unuseful or anything of the sort.

       But I refuse to listen to arguement about how 'we can predict averages' without asking for a proof, because the statement is simply not accurate.  That is all.

36048. Dikran Marsupial at 02:33 AM on 10 June 2014
       Climate is chaotic and cannot be predicted
       

       nickels, the kind of proof you are asking for us unavailable in many fields, but that does not stop similar results being used in a wide range of others, which is why we have computational fluid dynamics, rather than mathematical fluid dynamics.  There are many problems that you can only solve by simulation, rather than in closed form.  This does not prevent them from being rigorous, many excellent mathematicians (some of them in the same building as me) work on fluid dynamics (and indeed climate modelling).

36049. nickels at 02:19 AM on 10 June 2014
       Models are unreliable
       

       @KR

       And by the way, I am making honest, serious arguments about V&V.

       You are engaging in non-arguments and strict scholastic bullying.  Just for the record, you will convince no one with that approach, only distance them further from engaging in your cause.  Good luck.  I will not respond to you after this.

36050. nickels at 02:16 AM on 10 June 2014
       Climate is chaotic and cannot be predicted
       

       @DSL

       Your science is not going to get very far (and hasn't) when you shoot down people that point the issues with your scientific method rather than take them seriously and consider how to address them.

       Best of luck.

        

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