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Comments 47451 to 47500:

47451. barry1487 at 22:23 PM on 17 March 2013
       Watts Interview – Denial and Reality Mix like Oil and Water
       

       Tom,Of course one can ask the questions. I think Sphaerica may have been a little too tied to Watts' bad faith when saying it was not legitimate to ask questions about differences.

       Marcott's email address is in the 2013 paper. Put the question to him. You seem interested enough.

       No doubt you've already checked out the supplementary material.

       www.sciencemag.org/cgi/content/full/339/6124/1198/DC1

       Commenters at WUWT are saying that discrepancies should have been explained in the subsequent paper. It's this kind of attitude, which is prevalent, that annoys and can make anyone frustrated.

       If you get some answers, post them here.

47452. Bob Lacatena at 22:02 PM on 17 March 2013
       Watts Interview – Denial and Reality Mix like Oil and Water
       

       54, Ray,

       I don't know what you're talking about because I didn't really give much reason as to why the two would differ.  My only comment was that they were produced for different purposes with different degrees of attention, even if one is based on the other.  To compare the two is like claiming that the Cistine Chappel is a failure as art because Michelangelo's original sketches weren't as good.  [And no, I'm not comparing Marcott's work to Michelangelo's, it's just a useful analogy.]

47453. Bob Lacatena at 21:59 PM on 17 March 2013
       Watts Interview – Denial and Reality Mix like Oil and Water
       

       Tom, you keep completely missing the rather simple point, and in so doing you are giving fuel to Ray's confusion.

       Chapter 4 was written as supporting material for a thesis, which has a stated goal (already covered) and an implicit, unstated goal ("earn my Ph.D.").

       The Science paper was written, based on previous work begun for the Ph.D., as an end in and of itself.

       There is no suprise at all that there are differences.  If you or Watts or McIntyre have issues with the methods used in the Science paper, then address them.  But if your only focus is to point out that Chapter 4 was different from or less thorough than the Science paper, then you are simply wasting everybody's time and confusing everyone, because it is no surprise.

       If you have issues with the Science paper then state them.  Any similarities to or differences from Chapter 4 are irrelevant.

       Let's imagine that you were discussing sea level rise on an SkS comment thread, and in one comment you made a particularly good argument concerning CO2 levels.  Let's say you liked that comment so much that you expanded on it, corrected some mistakes you made, and published it as a blog post.

       Would it then be fair for deniers to dig up your original comment, and to complain that the original comment and the resulting post had differences?

       Why is this so difficult?

       And why do you insist on giving fodder for Ray to promulgate Watts' and McIntyre's idiocy?

47454. Tom Curtis at 21:45 PM on 17 March 2013
       Lessons from Past Climate Predictions: Syun-Ichi Akasofu
       

       Matthew L @40, there is no question that the GMST is initially flat at the start of the twentieth century, rises sharply, before being flat again, then rising sharply again.  This means it can be approximately modelled by a linear trend plus a regular wave (saw tooth or sine).  It is a far different thing to be able to show that it is better modelled by such a pattern than, for example, the global forcings resulting from solar, volcanic, GHG and aerosols.  Even if you could accomplish a superior fit with the linear trend plus regular wave (dubious, but possible if you add in extra parameters), that does not show a physical basis for your theory, which of course the explanation in terms of forcing has in spades.  Your graph showing an "underlying regular wave function" does no more than show the first point, ie, that the temperature trend in the twentieth century is not a simple straight line or parabola.  It tells us less than we knew just looking at the temperature graph.

       As to how Akasofu's predictions are fairing, if we consider this graph of the linear trend plus regular sine wave, not very well:

       

        

       For comparison, this is the fit between temperatures and known forcings:

       

       You should pay attention to the end of the graph.  There is sufficient discrepancy between the Akasofu prediction and actual temperatures that he must relly on the effect of short term events to explain the discrepancy.  But then he is left struggling to explain why La Nina years such as 2008 and 2011 are above his prediction rather than below it.  Indeed, we can test his prediction by removing ENSO as a factor by comparing temperatures El Nino years, La Nina years and La Nada years.  Once this confounding factor is removed, if there is anything to be said for Akasofu's theory, the pattern he predicts should be evident:

       

       Doesn't seem to work for him.

47455. Tom Curtis at 21:11 PM on 17 March 2013
       Watts Interview – Denial and Reality Mix like Oil and Water
       

       Ray @54, the graphs extend to approximately 2000 AD in both cases, but the Marcott reconstructions only extend to 1950, ie, 0 BP (by standard convention).  This can clearly be seen in Fig 1A from the science article, where the Mann 2008 EIV reconstruction is extended well past the Marcott reconstruction. 

47456. Matthew L at 21:02 PM on 17 March 2013
       Lessons from Past Climate Predictions: Syun-Ichi Akasofu
       

       Tom, thanks for the comments.  My extension of the WfT graph was simply to run the WfT graph again, take a screen cap and overlay it on the SkS graph.  It was just to give an idea of how things had gone since this article rather than to be figure accurate.  I think some of the problem is that when the article was written the WfT series would have been using HadCRUT 3 whereas it is probably now using HadCRUT 4.

       I note your comment "It should be noted that Matthew L's apparently sine like rate of change graphs are purely a function of using trend lengths approximately equal to, or greater than a half cycle.  Doing so guarantees a sine like graph for any underlying regular wave function".

       Surely that is the whole point?  The graph is trying to reveal the "underlying regular wave function".  I am not sure it is the case with scientists, but certainly the climate blogging community go out of their way to deny any kind of "regular wave function" exists in the climate and that it is purely an illusion caused by noise and that there is no physical cause known - as is clearly stated by Dana in this article. And my retort was that just because a cause is not known does not mean that there is no cause or that the apparent pattern does not exist - using the example of early solar astronomers seeing the sun spot cycle.

       I am not really trying to defend Akasofu in his prediction of the future trend which, as Dana stated in his reply to my post, is running cold relative to the actual figures.  However it is running cold rather less than the IPCC predictions are running warm.  I think he is "on to something" in that there does appear to be an "underlying regular wave pattern".  However, what I think he has missed, is that there is an upward trend in that wave pattern which is causing an increase in the underlying rate of change.

       What I see in this graph is that the short-term rate of warming may be lower than the IPCC was predicting, leading to a lower temperature in 2100, but that the rate of warming is gradually increasing which means a delayed but possibly larger warming subsequently.  Obviously that is reading an awful lot into one chart, and it would be interesting to build a hypothesis for what might be going on.

47457. Tom Curtis at 20:57 PM on 17 March 2013
       Watts Interview – Denial and Reality Mix like Oil and Water
       

       Sphaerica @53, looking closely at the two figures, there is only two methods common between the two, ie, the "Standard" method (Arithmetic mean of the 73 proxies) and the RegEM method.  In both graphs, the "Standard" reconstruction is extended through to 1950, but not further.  However, in the Thesis, the value of the "Standard" reconstruction at its termination (1950) is -0.4 C; whereas in the Science article it is nearly +0.3 C.  In the thesis, the terminal value for the RegEM method is 0.0 C, whereas in the Science paper it is about 0.05 C.

       Focussing on the difference in the Standard (Arithmetic mean) method,

       1)  The difference betwen the two is not due to a different terminal point, as both terminate in 1950.

       2)  It is not due to employment of a different method, as an arithmetic mean is well defined.

       3)  No difference of purpose can make a difference in the result of the algorithm.

       A difference of 0.7 C degrees in the same terminal position using the same method is something that requires explanation.  That explanation is likely to be in the form of an enhanced proxy in the Science paper due to updated proxy data, more rigorous interpolation of data, or infilling by some other method.

       If the two graphs had different terminal dates, your point would have merit.  It may even have merit in explaining why greater effort was taken to ensure as many proxies as possible extended to 1950 - but it does not explain how the later was accomplished and hence does not explain the difference. 

47458. Ray at 20:47 PM on 17 March 2013
       Watts Interview – Denial and Reality Mix like Oil and Water
       

       Dana @38  I didn't criticise the post, unless saying "I was rather surprised"  is criticism which I don't think it is but you apparently do.  Fair enough, we differ on the semantics. As for others who have taken me to task re the Figures in the PhD and Science papers, at Clmate Audit a comparison has been made of the later sections of the figures in question which suggest Sphaerica @37 may (note I say may not is) be somewhat mistaken in his comments as to why the Figures differ.  The comparisons made by Steve McIntyre (who is a competent statistician) show both Figures do cover the periods 1961-1990.  Perhaps he is mistaken however and Sphaerica is not althogh Tom Curtis @ 47 suggests he, Sphaerica, may be.  I would not, of course, presume to comment on what the outcome of this attention to the Marcott Science paper will be but the saga of the Joelle Gergis paper perhaps could be borne in mind when commenting, particularly when commenting on Steve McIntyre

47459. philipm at 18:03 PM on 17 March 2013
       2nd law of thermodynamics contradicts greenhouse theory
       

       I want to post here my admiration of the persistence of those who have kept up with almost 1000 posts rebutting a rather obviously flawed argument, that starts from failing to observe that you can’t apply the 2nd law of thermodynamics unless you have a closed system. There is a continuous influx of energy from the sun, so the ground and atmosphere aren’t a closed system. Case closed.

       If Gerlich really is physics professor at an apparently good university who has real students, they should demand a refund if this is the quality of his understanding.

       BTW there are a few dead links in the Notes:

       • http://groups.google.com/group/rabett-run-labs?hl=en
       • http://scienceblogs.com/deltoid/2009/03/gerlich_and_tscheuschner_oh_my.php
       • http://tamino.wordpress.com/2009/03/07/open-thread-11/
47460. Rob Painting at 17:19 PM on 17 March 2013
       Matt Ridley Risk Management Failure Deja Vu
       

       Roger Dewhurst - your comments are on the wrong thread. See: Ridley, Murdoch and Lomborg Attempt to Greenwash Global Warming.

       Given the prior analyses of satellite greening show opposing trends what is so special about the latest as-yet-unpublished study? See you over at the other thread.

47461. Rob Painting at 17:12 PM on 17 March 2013
       Water vapor is the most powerful greenhouse gas
       

       Absolutely Doug. But it gives insight into how some contrarians operate.  

47462. Tom Curtis at 14:20 PM on 17 March 2013
       Lessons from Past Climate Predictions: Syun-Ichi Akasofu
       

       Before responding to Matthew L @35, I checked a few details, which themselves raise additional issues.  The least important of these is that the graph of the running five year average of the Wood for Trees (WfT) temperature index is offset by about - 4 months.  Because of the steep slopes in the area, that offsets the start point of the prediction by about 0.005 C.  Having noted that, that seems inconsequential to me.  I note it, howeve, in case anyone else finds the same discrepancy.

       Also of little consequence, Matthew L's extension of the WfT observed index is too low.  On WfT, the low point around 2010 is no lower than that around 2007.  Matthew, however, places it around 0.005 C lower.

       The most important issue, however, is that Akasofu's prediction is incorrectly stated by Akasofu. In all his figures, Akasofu shows a sine like wave in representing his 60 year cycle.  That is consistent with the various indices (AMO, PDO) that he presents as evidence of that oscilation.  Therefore, his prediction is of a sine like oscilation superimposed on a linear 0.5 C per century trend.

       In a sine like oscilation, however, as the wave approaches the peak or trough, the slope of the sine like component of the wave approaches zero.  That means, at the peaks and troughs, the underlying 0.5 C per century trend should be evident.  Given that Akasofu states that the most recent peak was in 2000, and the most recent trough in 1970, he should predict a 0.05 C per decade trend for the ten years (or indeed, any symetrical interval) bracketing those years.  So, his predicted trend from 1995-2005 is 0.05 C per decade.  It is actually 0.213 C per decade (GISTEMP; NOAA: 0.212; HadCRUT3: 0.234; HadCRUT4: 0.222).  1970 fairs a little better, with trends ranging from 0.087 to -0.016 C per decade (GISTEMP and HadCRUT4).

       Of course, with a sine wave fluctuation, the maximum negative trend is predicted to be reached in 2015, so the trend from 2000-current is predicted to be significantly negative (0.075 C/decade).  In fact, it is positive (GISTEMP: 0.072 C/decade; NOAA: 0.044 C/decade; HadCRUT3: 0.008 C/decade; HadCRUT4: 0.043 C/decade). 

       However, Akasofu can only avoid refutation of his hypothesis by the recent data by acknowledging that over the short term, the impact of ENSO and volcanism dominate over long term trends.

       That does not save him, however, for his prediction, with a sine like oscilation, shoud be for a maximum positive trend at around 1985, with the trend gradually developing to that point, before gradually falling back to 0.05 C per decade 15 years later.  In fact, the trend from 1970 to 2000 is indistinguishable from a linear trend plus noise (as shown by the plateau in the trend, see graph below).  The same can also be said of the trends from 1940 to 1970, and from 1910 to 1940.  Indeed, the model of a sine wave superimposed on a linear trend performs very poorly in predicting trends:

       

       (Successive 217 month trends for GISSTEMP and linear plus sine wave models. Click on graph for larger image.)

       It should be noted that Matthew L's apparently sine like rate of change graphs are purely a function of using trend lengths approximately equal to, or greater than a half cycle.  Doing so guaranttees a sine like graph for any underlying regular wave function (although the amplitude of the wave function approaches zero as the trend length gets large relative to the full underlying wave length.)

       As previously noted, Akasofu can accomadate this discrepancy by allowing for large short term fluctuations related to ENSO.  If he does so, however, he must explain why he makes no attempt to remove the ENSO signal, and why the underlying trend with the ENSO signal removed is so strongly positive.

       Finally, it could be reasonably argued that I am being too kind to Akasofu.  In modeling his prediction, I have used a regular sine wave with an amplitude of 0.2 C and a wave lenght of 60 years.  In fact, in his only direct presentation of the wave I am aware of, he shows two full cycles, with no cycle having the same duration, amplitude or shape of any other:

       

       (From Akasofu, "On the recovery from the LIA", Natural Science, 2010, Fig 4d)

       Allowing this, essentially freehand modification means Akasofu could have fit any sine like pattern in the tempeature data, regardless of its cause.  It also means the pattern he fitted is not predictive, for no information is contained about the lengths or amplitudes of future "cycles", given that these parameters are allowed to vary freely.

47463. Matt Fitzpatrick at 13:59 PM on 17 March 2013
       February 2013 Arctic Sea Ice Death Spiral Update
       

       In fairness, the perspective in the second figure exaggerates values below 30 thousand km³ in more recent years.

       But the circle (spiral) graph is stunning. It even provides a tidy disappearing point for when months start hitting zero. If not for that, I imagine some people might take the flat segment on a non-circular graph between September 20X0's zero and September 20X1's zero as "evidence" of no warming.

47464. Leto at 13:55 PM on 17 March 2013
       Matt Ridley Risk Management Failure Deja Vu
       

       Hi Roger,

       When I asked for details, I was wondering whether Ridley had mounted any sort of sophisticated botanical argument of relevance to the science of climatology. If you can't answer without mentioning fears of a mini-ice age and mass starvation on the back of "lacl of warming for over a decade", or without dismissing concerns about AGW as "inane", it does give me some idea of the audience he is pitching to, at least.

       Comment policy on this site prevents me from saying much more of what I think, so I'll leave it at that. Some of the more patient folk here at SkS might be ready to discuss your ideas with you.

       I'm not sure you've done Ridley any favours here.

       Leto.

47465. Bob Lacatena at 13:44 PM on 17 March 2013
       Watts Interview – Denial and Reality Mix like Oil and Water
       

       52,

       Tom, the paper does have a different focus from Chapter 4 of the thesis, because Chapter 4 of the thesis was preliminary material in support of 3 distinct and separate goals of the thesis, but with no other intent of its own, while the paper which grew from and builds upon Chapter 4 has a purpose in and of itself.  The distinction is critical to the discussion.  The distinction is, in fact, the crux of the argument.

       When Chapter 4 consisted of a reconstruction in support of questions concerning paleo issues several thousands of years ago, the only relevant aspect of modern temperatures within Chapter 4 was some overlap with more recent proxies so as to calibrate and validate the temperature record extending further back.

       When Chapter 4 grew into a paper intended explicitly to comment on the variability of climate for the past ten thousand years, as compared with recent climate change, then the issue of more recent temperature change became relevant and was included.

47466. Doug Hutcheson at 13:30 PM on 17 March 2013
       Matt Ridley Risk Management Failure Deja Vu
       

       Roger Dewhurst @ 33, your claims seem to be extraordinary and require extraordinary proofs. For a quick review, I recommend having a look at the following articles here:

       • http://www.skepticalscience.com/co2-plant-food.htm
       • http://www.skepticalscience.com/heading-into-new-little-ice-age.htm
       • http://www.skepticalscience.com/global-warming-stopped-in-1998.htm
       Moderator Response: [DB] Thank you. You pre-empted the need for further Moderator intervention. Interested parties may engage Roger Dewhurst on the appropriate thread.
47467. Doug Hutcheson at 13:17 PM on 17 March 2013
       Water vapor is the most powerful greenhouse gas
       

       Rob Painting @ 166, the extraordinary claim that the net response to a doubling of CO₂ would be a temperature increase of 0.2^OC requires more than "a tiny kernel of truth", I would have thought. I have emailed Radio National to see if they have a transcript of the interview and will post here again, if I get a response.
       

47468. Tom Curtis at 13:05 PM on 17 March 2013
       Watts Interview – Denial and Reality Mix like Oil and Water
       

       barry @51, the paper does not have a different focus from Chapter 4 of the thesis; and nor does it, except for minor modifications, have different methods.  Further, pointing out that it has different methods (minor as the changes are) does not answer the question as to which difference in the methods resulted in the changes in the data presented in otherwise equivalent graphs.  Nor is it clear from the description of the methods in the paper and thesis in what the difference lies.

       While I agree completely with your final sentence, the issued raised in bad faith by McIntyre and Watts could also be raised in good faith.  Merely pointing out that McIntyre and Watts do not ask the questions in good faith does not show the questions do not need an answer.

47469. barry1487 at 11:53 AM on 17 March 2013
       Watts Interview – Denial and Reality Mix like Oil and Water
       

       "And yet, as might be expected, Dr. Marcott chose to build upon his previous work and to take it in a new direction, one relevant to a major issue of the day, anthropogenic climate change."

       
       Anthony Watts did the same for the US temperature record, building upon the work of Fall et al (he was a co-author) when drawing up his unpublished effort on station exposure. Both papers give a pie chart on percentage of stations with different classification. They are different from each other.
       

       Should we now imply that A Watts has done something questionnable by 'altering' the latter graph?
       

       No - the papers have a different focus (and methods). Same with Marcott. Honest participants would take the trouble to find out why there are differences, and not just make implication with 'questions' they are not interested in answering for themselves.
       

47470. Roger Dewhurst at 11:50 AM on 17 March 2013
       Matt Ridley Risk Management Failure Deja Vu
       

       Ferns, cycads, horsetails and the like evolved in palaeozoic times with far higher levels of carbon dioxide in the atmosphere.  Most of the evolution of the angiosperms, at least to generic and family level, had taken place before the end of Jurassic times, also in an atmosphere much richer in carbon dioxide.  The level of carbon dioxide in the atmosphere today is sub-optimal for most plants.  This is of course a fact well known to the operators of commercial greenhouses.  It is no surprise really, and to be expected, that the increase in atmospheric carbon dioxide in recent decades has stimulated plant growth.  Should the inane pleas for reduction in atmospheric carbon dioxide actually succeed plant growth will slow and starvation will become the norm in much of the third world.  Should we be entering a mini ice age, which is a distinct possibility given the lacl of warming for over a decade and the low level of sunspot activity, we might just need all the carbon dioxide we can get into the atmosphere !

       Moderator Response: [DB] Any further discussion of this line needs to be taken to the CO2 is plant food thread. Off-topic sloganeering struck out. Interested parties may engage Roger Dewhurst on the appropriate threads noted by Doug Hutcheson.
47471. Roger Dewhurst at 11:37 AM on 17 March 2013
       Matt Ridley Risk Management Failure Deja Vu
       

       Leto.

       Ridley's initial claim is that the earth is getting greener and he presented good evidence for that.  Do you wish to dispute that point?

        

       He also claimed that the increase in atmospheric carbon dioxide contributed to that greening arguing, on correct botanical grounds, that carbon dioxide is plant food.

        

       Do you wish to dispute that point?  Are there any point in his talk that you would like to dispute?  If so what are they?

47472. barry1487 at 11:20 AM on 17 March 2013
       Watts Interview – Denial and Reality Mix like Oil and Water
       

       DSL,

       
       

       Alas, Poole could've used a more robust representation of "climate change" instead of just equating it with temperature as Luntz does.  Climate change somewhat obviously can be changes in temp, general circulation, precipitation, weather patterns, wind, cloud cover, frequency of "extreme" events, etc.
       

       
       

       While illuminating the definition of climate change in this way may be laudable, Poole's thesis was on the politicisation of language, and he articulated the intent of the political actors at the time. It would be great if the faux skeptics just dropped the talking point, but seeing as they bring it up as a political argument (cf Anthony Watts) it's worthwhile knowing how discussion of the terminologies actually played out. Watts claims that AGW 'proponents' fiddled with the language. But it wasn't the scientists or the media or Greenpeace that focussed on the political ramifications of the two phrases, it was those with vested interests in downplaying AGW. It still is.

       Watts is not only wrong, his criticism is completely misdirected.
       

47473. Rob Painting at 11:15 AM on 17 March 2013
       Water vapor is the most powerful greenhouse gas
       

       Doug - it's a bogus claim, but there is a tiny kernel of truth in there. Increasing the water vapour content of the atmosphere  would indeed block more sunlight from reaching the Earth's surface. It isn't sufficient to counteract the warming impact from increased water vapour though. 

47474. Treesong2 at 10:32 AM on 17 March 2013
       2013 SkS Weekly News Roundup #11
       

       The link for 'Why saving the planet means saving the economy, too' is the same as the one for 'Five companies vie to build wind farms off North Carolina coastline'.

       Moderator Response: [JH]Link fixed. Thank you for bringing this to our attention.
47475. Doug Hutcheson at 10:14 AM on 17 March 2013
       Water vapor is the most powerful greenhouse gas
       

       I was listening to Radio National (Australia) yesterday and heard Pielke Jr claim that water vapour actually has a negative forcing, meaning a doubling in CO₂ would cause a global temperature change of 0.2^oC. I was astounded, not surprisingly! Hands up all those scientists who think CO2 has a negative forcing? Anyone? (Cue sound of crickets ...)

47476. DSL at 09:15 AM on 17 March 2013
       Watts Interview – Denial and Reality Mix like Oil and Water
       

       TC, Sph: in what world are you not both right?  Questioning the difference between the graphs is a legitimate enterprise if done to further one's understanding of the research.  I questioned the difference myself until I saw the reasons (confirmed more completely by TC).  It's clear from Watts' and McIntyre's rhetoric that they have no interest in furthering their understanding or disseminating that understanding to the people they've already confused.

47477. Leto at 08:47 AM on 17 March 2013
       Matt Ridley Risk Management Failure Deja Vu
       

       Hi Roger @30,

       Care to put some detail into that claim? Given all of the nonsense Ridley has spouted in the past, I would be surprised if he got something right, but it's always interesting to hear the argument.

47478. jyushchyshyn at 08:44 AM on 17 March 2013
       State Department Downplays the Climate Impact of Keystone XL
       

       If the Northern Gateway pipeline is also rejected, then rejecting Keystone will slow down oilsands development. But rejecting Keystone will not have any effect on what really matters in the fight against global warming; how much energy is provided by the combustion of hydrocarbons. If Keystone is rejected and if we continue to use hydrocarbons as we have to now, then we would just get the oil from OPEC. On the other hand, if someone actually had a plan to make the oil delivered by Keystone unnecessary, then whether or not the pipeline is built would be moot. If Keystone were built but not used, would that be such a bad thing, except for its investors.

47479. dalyplanet at 08:44 AM on 17 March 2013
       February 2013 Arctic Sea Ice Death Spiral Update
       

       Nice graphics and the loss of volume is an eye popping if not heart stopping bit of information

47480. Roger Dewhurst at 08:38 AM on 17 March 2013
       Matt Ridley Risk Management Failure Deja Vu
       

       Attacks on the messenger but the message escapes unscathed.  Rightly so becuse he stuck to facts.  Although Ridley is not a botanist his botanical arument was totally correct.

47481. Bob Lacatena at 08:29 AM on 17 March 2013
       Watts Interview – Denial and Reality Mix like Oil and Water
       

       ...given the similarity of these descriptions...

       So what?  I've said repeatedly that the Nature paper was clearly based on Chapter 4 from the thesis, and it makes sense to have done so.  Of course there were similarities.  The question Watts posed was why was that particular change (adding the recent temperature record) made to the paper when it was not the original thesis, and the answer is clearly that it was not necessary given the objective of the original project.

       That's all that matters here.  Watt's inane query was "I wonder why the difference" and the answer is "because it was irrelevant to the purpose of the original thesis."

       That's all.

       Therefore it is intirely reasonable to ask about differences between them.

       No, it's not.  The reasons for the differences are obvious, and the reasons for pursuing it further are obvious as well – to stir up false controversy and to cast doubt upon the motivations and methods of Marcott. That's all this is, is a Watts/McIntyre denial hatchet-job, and it has no foundation whatsoever.

47482. LarryM at 07:48 AM on 17 March 2013
       February 2013 Arctic Sea Ice Death Spiral Update
       

       The first Death Spiral graphic is visually striking and clearly shows the loss of sea ice in all seasons.  Another permutation that might complement it and more clearly show the differences between seasons is for the radial scale to show, rather than absolute volume in km³, the percentage of the volume in 1979 that remains.  I think it would show that the summer/fall ice is disappearing exceptionally fast.

47483. Tom Curtis at 07:12 AM on 17 March 2013
       Watts Interview – Denial and Reality Mix like Oil and Water
       

       Sphaerica @46, from the Science article:

       "We then assessed the sensitivity of the temperature reconstruction to several averaging schemes, including an arithmetic mean of the data sets, a 30° × 30° area-weighted mean, a 10° latitudinal weighted mean, and a calculation of 1000 jackknifed stacks that randomly exclude 50% of the records in each realization (Fig. 1, C and D, and fig. S4). Although some differences exist at the centennial scale among the various methods (Fig. 1, C and D), they are small (<0.2°C) for most of the reconstructions, well within the uncertainties of our Standard5x5 reconstruction, and do not affect the long-term trend in the reconstruction."

       From the thesis:

       "To test the reproducibility of our two methods for reconstructing the temperature stack, we experimented with various ways of calculating the globally stacked temperature anomalies (Figure 4.3 a,e). We divided the records into 10° latitudinal bins and weighted them by their cosine of latitude to test the sensitivity of our datasets being skewed toward the northern hemisphere. A jack-knife technique, where for each of the Monte Carlo simulations 50% of the records were randomly excluded, was also implemented to determine the sensitivity of the global stack to any one record or group of records. While some differences exist at the centennial scale amongst the various methods (Figure 4.3 a), they are very small (<0.2°C) for most of the reconstruction, well within the uncertainties of our stacked temperature record, and do not affect the long-term trend in the reconstruction, demonstrating the robustness of our record at the multi-centennial and multi-millennial scale."

       And regarding the specific figure under discussion, from Science:

       "(CandD) Global temperature anomalies stacked using several methods (Standard and Standard5x5Grid; 30x30Grid; 10-lat: Arithmeticmeancalculation, area-weighted with a 5° × 5° grid, area-weighted ith a 30° × 30° grid, and area-weighted using 10° latitude bins, respectively; RegEM and RegEM5x5Grid: regularized expectation maximization algorithminfilled arithmetic mean and5°×5°area-weighted). The gray shading [50% Jackknife ( Jack50)] represents the 1s envelope when randomly leaving 50% of the records out during each Monte Carlo mean calculation. Uncertainties shown are 1s for each of the methods."

       And from the thesis:

       "Comparison of different methods and reconstructions of global and hemispheric temperature anomalies.

       a, Mean values of our global and hemispheric temperature anomalies using several methods (Standard – Arithmetic mean calculation; StandardNH – Arithmetic mean calculation of Northern Hemisphere records only; CosLat – Arithmetic mean calculation, cosine of latitude weighted; RegEM – Mean calculation using RegEM). The gray shading (Jack50) represents the 1! band when randomly leaving 50% of the records out during each Monte Carlo mean calculation."

       There is no doubt, given the similarity of these descriptions that Fig 1 c from Science, and Fig 4.3 a from the thesis serve the same purpose within their respective documents.  Therefore it is intirely reasonable to ask about differences between them.

       What is not reasonable is to make insinuations of fraud when an entirely adequate potential reason is shown in the same group of graphs.

47484. Bob Lacatena at 05:44 AM on 17 March 2013
       Watts Interview – Denial and Reality Mix like Oil and Water
       

       Tom,

       The purpose of the project as a whole is explicitly and clearly stated in the opening chapter:

       This dissertation addresses three issues related to paleoclimate in an attempt to shed new light on the mechanism and timing of climate and glacier changes in the past.

        While the individual chapters may have strayed into other potential conclusions and uses, and while it may have evolved by this point in time to have a different application and to be published as a paper in its own right in Nature, there is no doubt that this was not the original intent, so to complain explicitly about the lack of careful comparison to current temperatures is an erroneous and baseless complaint.

       And I did not dispute that elements of the paper did evolve into Marcott et al.  Quite to the contrary, I explicitly stated:

       And yet, as might be expected, Dr. Marcott chose to build upon his previous work and to take it in a new direction, one relevant to a major issue of the day, anthropogenic climate change.

       All of my points still stand, specifically:
       

       1. The purpose of the original project, regardless of tangents, was not to evaluate past climate as a benchmark for current climate change, so no complaint can be made about the completeness of the thesis for that purpose.
          
       2. It is not only not unexpected, but rather to be expected that Marcott would use this as a foundation for further work, including application directly to current climate change.  it would be surprising if he had not done so.
          

       The Watts/McIntyre complaint is a complete and total misdirection, and anyone who falls for it should be ashamed of themselves (for failing to be more skeptical and sensible).  Anyone who fell for it should do some introspection about what their own motives and desires might be (i.e. to ascertain the truth, or to arrive at a seeming truth which supports their hoped for outcome).
       

47485. DSL at 04:33 AM on 17 March 2013
       Southern sea ice is increasing
       

       newtja, Corr & Vaughan (2008) does not attempt to assess or quantify the effect of volcanic venting on the Pine Island glacier.  The eruption discussed occurred roughly 2k years ago.  It's possible that venting is helping the break up of PI glacier, but as you can see from the article above, and from Shepherd et al. (2013), there are greater factors involved.  You might also check out Vaughan & Corr (2012).  Here are the last lines of their abstract:

       "We conclude that ice-shelf basal melting plays a role in determining patterns of surface and basal crevassing. Increased delivery of warm ocean water into the sub-ice shelf cavity may therefore cause not only thinning but also structural weakening of the ice shelf, perhaps, as a prelude to eventual collapse."

47486. rugbyguy59 at 04:27 AM on 17 March 2013
       2013 SkS Weekly News Roundup #11
       

       As a Canadian, when I first saw the headline Canada Losing its Seasons I thought "Oh no, another 'kids won't see snow' comment." However the article notes a variety of changes that are already started and changes that are much less weather dependent than "no snow" allusions. Still I'd be naive to think deniers won't (incorrectly) use it.

       It all makes me wonder if I shouldn't send the kids north to get established as those who are their first usually benefit the most. Of course that would be based on an orderly migration north. With who knows how many millions making the trek I get the feeling the migration may not be particularly orderly.

47487. newtja at 03:57 AM on 17 March 2013
       Southern sea ice is increasing
       

       How do the explanations in this article correspond to the 2008 paper by Corr and Vaughn in Nature Geoscience about volcanism affecting the Pine Island Glacier?

47488. John Mason at 02:17 AM on 17 March 2013
       Death in Jurassic Park: global warming and ocean anoxia
       

       PS - this paper may be of interest to you: it does concern deeper water facies from the Toarcian:

       An open marine record of the Toarcian oceanic anoxic event

        Abstract.
       6‰) negative excursion in d13Corg that, based on radiolarian biostratigraphy, is a correlative of the lower Toarcian negative CIE known from Pangaean epi-and pericontinental strata. A smaller negative excursion in d13Corg (ca. 2‰) is recognized lower in the studied succession. This excursion may, within the current biostratigraphic resolution, represent the excursion recorded in European epi-continental successions close to the Pliensbachian/Toarcian boundary. These results from the open ocean realm suggest, in conjunction with other previously published datasets, that these Early Jurassic carbon cycle perturbations affected the active global reservoirs of the exchangeable carbon cycle(deep marine, shallow marine, atmospheric).

       Moderator Response: [RH] Shortened link.
47489. John Mason at 02:09 AM on 17 March 2013
       Death in Jurassic Park: global warming and ocean anoxia
       

       @ mlyle - sure: however the authors do state the following:

       Evidence of an extinction event has
       been reported in western Europe (e.g., [24,33–35]), South
       America [36–37], Siberia [38] and northern Africa [39]. Although
       definitive cause-effect relationships are not yet established, the
       extinction has either been linked to the development of widespread
       anoxia [27,37,40–41], or to global warming [32,42].

       Thus it seems a reasonable point to report upon. I agree that most Toarcian oceanic crust has been recycled, but the widespread occurrence of these black shales suggests something was afoot. Bearing in mind that shelf areas are particularly productive in terms of biodiversity, anoxia in these areas would have a particularly devastating impact.

       N and P would be relatively easy to get into the system if widespread terrestrial erosion of soils was going on at the time.

47490. DSL at 00:48 AM on 17 March 2013
       Watts Interview – Denial and Reality Mix like Oil and Water
       

       And has McIntyre or Watts actually asked Marcott about the differences (instead of quite publicly insinuating that Marcott is guilty of some sort of fraud)?  Have you addressed this issue with the presumably more "skeptical" Watts and McIntyre, Ray?

47491. mlyle at 00:29 AM on 17 March 2013
       Death in Jurassic Park: global warming and ocean anoxia
       

       You have to be careful to make estimates of global ocean conditions from one locale, especially from the shelf-slope region. I can find basins today that are anoxic, but that doesn't mean the whole ocean is today.  The paper puts forward an interesting hypothesis, but needs to show why one might expect this to represent global conditions. Unfortunately, there are few pieces of deep ocean floor preserved to actually test for global anoxia.  Also, to get hyperproductivity, the problem is to get N and P into the oceans, not C.

47492. Tom Curtis at 00:27 AM on 17 March 2013
       Watts Interview – Denial and Reality Mix like Oil and Water
       

       Ray @36, the graph you mention is not the only one to have altered between thesis and paper in Science.  Specifically Fig 1 G (Science; Fig 4.3 C in the thesis) also differs.  That figure shows the number of proxies available at different time periods.  Most importantly, in the thesis it shows less than 10 proxies extend into the twentieth century.  In contrast, in the Science article, shows 20 proxies available at the same time interval.  As the same proxies appear to be used in each, this suggests that either Marcott has recieved additional, more recent data for several of the proxies, or that the interpolation using RegEm (as discussed both in paper and thesis) has been more extensively applied.  

       Regardless of the course, less than ten proxies is a very limited sample for determining global surface temperature and such a small sample is likely to have considerable biases.  Therefore, more than doubling the number of available proxies is likely to result in changes in the reconstruction where the proxies are sparce (twentieth century), although adding the same number of proxies will have little effect where the proxies are more extensive (ie, prior to AD 1500).

       Failing further evidence to the contrary, this would appear to completely answer the issues raised.  You may want to ask yourself why this change in the number of available proxies has not been commented on at WUWT.

47493. Tom Curtis at 00:13 AM on 17 March 2013
       Watts Interview – Denial and Reality Mix like Oil and Water
       

       Sphaerica @37, Chapter 4 of the thesis is specifically about the reconstruction of Holocene temperatures, and is analogous the Science paper, and has the same authors as the Science paper.  It is also noted that that chapter would be submitted to Nature for publication.  It is a reasonable supposition the Science paper is Chapter 4 as modified in the process of publication.  That Marcott adresses other issues in other chapters of his thesis is not germaine, and does not rebut the general equivalence of Chapter 4 and the Science paper.

47494. DSL at 23:51 PM on 16 March 2013
       Watts Interview – Denial and Reality Mix like Oil and Water
       

       Alas, Poole could've used a more robust representation of "climate change" instead of just equating it with temperature as Luntz does.  Climate change somewhat obviously can be changes in temp, general circulation, precipitation, weather patterns, wind, cloud cover, frequency of "extreme" events, etc.  

47495. MA Rodger at 23:33 PM on 16 March 2013
       Lessons from Past Climate Predictions: Syun-Ichi Akasofu
       

       I examined Akasofu's work last year as he was being used to support denialist argument presented by the GWPF. Was I being rather generous?

47496. shoyemore at 19:03 PM on 16 March 2013
       Watts Interview – Denial and Reality Mix like Oil and Water
       

       Ray #36,

       Anyone with a feeling for fair play would (I hope) agree that the accusations flung at Marcott over his PhD thesis are shrill and unjust. And also irrelevant.

       Ask yourself: Do the contents of Marcott's PhD thesis suggest any grounds for the recent paper to be withdrawn or modified in any way? Who will submit a comment to Science based on a difference in the results of the paper and the thesis?

       My answers are "No" and "Nobody".

       Theses often end up as papers or books, but in this case Marcott was not "working up" his PhD thesis as a paper, based on Sphaerica #37.

       I am glad to see the hysteria over Marcott et al is being mostly ignored by good science blogs. Nor has the paper been accepted without reservation among the climate-change blogging community. If anything, it has been greeted with a proper degree of caution, or real scepticism.

       http://scienceblogs.com/stoat/2013/03/11/a-reconstruction-of-regional-and-global-temperature-for-the-past-11300-years/

47497. meher engineer at 18:18 PM on 16 March 2013
       Death in Jurassic Park: global warming and ocean anoxia
       

       A useful article. A quote that may add to it says, "The oceans act like a sponge to draw down excess carbon dioxide from the air; the gas reacts with seawater to form carbonic acid, which over time is neutralized by fossil carbonate shells on the seafloor. But if CO2 goes into the oceans too quickly, it can deplete the carbonate ions that corals, mollusks and some plankton need for reef and shell-building.

       That is what is happening now. In a review of hundreds of paleoceanographic studies, a team of researchers from five countries found evidence for only one period in the last 300 million years when the oceans changed even remotely as fast as today: the Paleocene-Eocene Thermal Maximum, or PETM, some 56 million years ago.  In the early 1990s, scientists extracting sediments from the seafloor off Antarctica found a layer of mud from this period wedged between thick deposits of white plankton fossils. In a span of about 5,000 years, they estimated, a mysterious surge of carbon doubled atmospheric concentrations, pushed average global temperatures up by about 6 degrees C, and dramatically changed the ecological landscape." It appeared in an   article on "Ocean acidification rate mey be unprecedented" (see: http://www.earth.columbia.edu/articles/view/2951), that is worth looking at.  

       Moderator Response: [DB] The source paper for that article can be found here.
47498. barry1487 at 18:13 PM on 16 March 2013
       Watts Interview – Denial and Reality Mix like Oil and Water
       

       Sorry about the formatting. :(

47499. barry1487 at 18:12 PM on 16 March 2013
       Watts Interview – Denial and Reality Mix like Oil and Water
       

       In fact, perhaps the only individual to actually advocate changing the term from 'global warming' to 'climate change' was Republican political strategist Frank Luntz in a controversial memo advising conservative politicians on communicating about the environment:

       It’s time for us to start talking about “climate change” instead of global warming and “conservation” instead of preservation.

       “Climate change” is less frightening than “global warming”. As one focus group participant noted, climate change “sounds like you’re going from Pittsburgh to Fort Lauderdale.” While global warming has catastrophic connotations attached to it, climate change suggests a more controllable and less emotional challenge.

       
       I've quoted it once before on SkS; According to Stephen Poole in his book Unspeak...

        

       "The U.S., Saudi Arabia, and other oil-producing countries lobbied the U.N. in the late 1980s to change the language of early resolutions from 'global warming' to 'climate change' because the latter is vaguer and less frightening, and also because it doesn’t point the finger so directly at the burning of fossil fuels as the cause. While 'climate change' is scientifically correct (because a local climate might get colder rather than hotter), it obscures the fact that such changes will be a result of the rising mean temperature of the planet — i.e., of global warming."

       
       

       Poole mentions that part of his book at his blog, here (but there he says the talks occurred in the early 1990s). It's also referenced here. If correct, it might be worth mentioning that everyone who tried to change the language was on the 'skeptical' side of the debate.
       

       Moderator Response: [DB] Fixed link html.
47500. Leto at 16:57 PM on 16 March 2013
       We're heading into an ice age
       

       Hi there grindup,

       I must be having a slow day... Could you spell out the argument for me?

       Thanks.

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