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Comments 44551 to 44600:

  1. Heartland's Chinese Academy of Sciences Fantasy

    I've worked in advertising and marketing my whole professional career, and I've NEVER flatout lied and misrepresented information the way the Heartland Institute and their ilk does. I guess that's why I work at an "agency" and not a "think tank."

  2. 2013 SkS Weekly News Roundup #24A

    Re the film on Nuclear, it would be much easier to suport nuclear power as the solution to climate change if only it was thorium based.  Walk away failsafe; cannot produce weapons grade material; far more efficient that uranium based power plants; far less waste of much shorter half life; thorium based nuclear power is such an obvious answer to our need for energy with buring fossil fuels.  Pity common sense doesn't rule in place of vested interests.

  3. Heartland's Chinese Academy of Sciences Fantasy

    I'll assume the Chinese Academy meant it in a good way, but actually what they ended up doing was feeding the trolls.

  4. Murry Salby - Confused About The Carbon Cycle

    Btw, the Salby paper appears to be in purgatory.  Everyone's been waiting now for about two years. Nothing yet.  

  5. Murry Salby - Confused About The Carbon Cycle

    Any claim is easily said.  Providing evidence to support the claim is more difficult. Civil engineer, how about exercising some civility and engineering a discussion around where the SkS links failed?  That way you can provide a valuable service to the entire community and become believable.  

  6. An estimate of the consensus project paper search coverage

    Daniel, the direction of research can be an indication of the paper's understanding of mainstream climate science.  A team of herpetologists decides to study the long-term migration of a frog species.  The team finds that the frog species is moving northward by about three kilometers per decade.  The team writes the migration up and, in the discussion section, speculates about the future of the movement.  The team assumes current mainstream estimates of future warming for the region, noting that the species may end up being caught between a rock and a hard place, since there is a natural barrier a few km to the north.  That speculation is represented in the abstract.  This paper explicitly endorses the mainstream theory (AGW), since the mainstream theory is the only one taken into account.  The mainstream theory (is this what you refer to as a "myth"?) is anthropogenic global warming, and implicit in that theory is the continuation of warming as long as the greenhouse effect continues to be enhahnced.

    True, it would be very difficult for such a paper to go against the mainstream view.  After all, to do so would be to explicitly reject the mainstream theory of climate, and a reason would need to be provided.  As science naturally becomes more interdisciplinary, trust is a major issue.  The herpetologists must trust climate modeling to give them a realistic basis for useful speculation.  In that way, the use of the mainstream view is a vote of confidence for the mainstream view.  It's not simply "well, we were forced to use it."  The herpetologists didn't have to use it.  They could have simply relied on an extrapolation of their own data.  Such an act would be less useful, even if it were tied to a physical mechanism (e.g. according to local data, it's getting warmer in this region).  

    The herpetologists would be especially driven toward speculation if they had long-term data, and the recent data suggested highly unusual activity.  There's absolutely nothing wrong with such speculation.  It reflects the concern the scientists have for their research areas.  I can't count the number of times people have essentially tried to argue (toward me) that nature is conservative and any unusual behavior or "wild" speculation must be the result of scientists trying to make an extra buck or keep their jobs.  No.  If the basic inputs change (e.g. rising system energy storage), every element of the system changes.

    By the way, what were you referring to as a myth?

  7. Sudden_Disillusion at 21:27 PM on 14 June 2013
    A Miss by Myles: Why Professor Allen is wrong to think carbon capture and storage will solve the climate crisis

    All geoengineering solutions that I know of are inherently unsustainable. Except this one: http://www.youtube.com/watch?v=vpTHi7O66pI (inspiring TED talk by Allan Savory)

    If this works it not only reverses desertification, provides stable food supplies for local people, and enhances biodiversity, but also addresses global warming by greatly increasing the worlds biomass ergo capturing and storing CO2.

    I do not understand why this is nowhere to be found in the media. Here comes your daily conspiracy theory ;-)

     

  8. Dikran Marsupial at 20:58 PM on 14 June 2013
    An estimate of the consensus project paper search coverage

    Daniel, I suggest you read the paper, the criterion for determining whether a paper supports AGW are stated as clearly as one could reasonably expect.  A paper on statistical downscaling (an area of climatology in which I have worked) is not a paper that seeks to determine whether climate change is anthropogenic or not, but it would not be unusual for such a paper to motivate the need for the study by mentioning in the abstract that the majority of climate change has ocurred due to fossil fuel use.  In your view, would such a paper endorse AGW, and at what level according to the stated criterion for the TCP?

  9. An estimate of the consensus project paper search coverage

    Dikran,

    You seem to be echoing my concern in your last sentence.  If a paper mentions climate change, but makes no mention of the cause, how can it be considered to support AGW?  Even if the myth were true, many of the papers would still not likely take a stance, as most of these papers were not written by climatologists.  The term "climate change" was not the issue in my post, but its selection as criteria for the paper.

  10. 2013 SkS Weekly News Roundup #24A

    Conservative Think Tanks and Climate Change Denial Books needs a link to http://www.yaleclimatemediaforum.org/2013/06/manufacturing-uncertainty-conservative-think-tanks-and-climate-change-denial-books/

    Moderator Response:

    [JH] Link inserted. Thank you for bringing this to our attention.

  11. New study by Skeptical Science author finds 100% of atmospheric CO2 rise is man-made

    I have responded here.

  12. Murry Salby - Confused About The Carbon Cycle

    Responding to civil engineer  from here.

    "I don't find the sks links that convincing" is not a useful comment. If you dont explain the problems you percieve with responses to Salby, then how are we to distinquish this from "I prefer a reassuring lie to an inconvenient truth"?.

  13. A short history of carbon emissions and sinks

    Daniel @3, two points:

    1)  The NH seasonal CO2 flux is dominated by the growth and fall of leaves on deciduos trees.  This is shown in measurements of CO2 concentration from Barrow (Alaska):

    Looking closely, you can see that January corresponds to the nearly flat plateau at the peak of CO2 conenctration, and hence with a flux minimum.  That is unsurprising in that the leaves have fallen, but are to cold to decompose.  In contrast, July corresponds to the steep downward slope in CO2 concentration.  Again this is unsurprising in that summer is a period of maximum plant growth.

    The net effect of this, and of providing data for just two months is that the Jaxa data gives a very poor indication of annual CO2 flux from northern dedediduous forests, or indeed, northern tundra where similar considerations arise.  It represents a snap shot of one month of maximum flux and one month of near zero flux in a cycle that is close to carbon neutral.

    Similar considerations apply to the tropical forest, but are nowhere near as strong in that the difference between summer and winter growth are much smaller in the tropics.

    2)  Much of the original extent of the northern deciduous forest was deforested in the early twentieth century, or before.  Since then, many areas previously denuded of trees have been allowed to regrow forest, and some forests still used for lumber are more heavilly managed allowing a greater retention of carbon.  In contrast, large scale deforestation in the tropics has been a novel feature of the last few decades.  Further, it is very poorly managed, with extensive logging in areas supposedly set aside as nature reserves.  Consequently part of the difference between NH deciduous forest and tropical forest fluxes is simply a result of changes in land use rather than natural fluxes.

    Given these two factors, the Gosat data is almost useless in isolation for determining the net natural flux for tropical forest and northern deciduous forest.  It may well be useful when coupled with additional detailed knowledge, but I am not an expert and cannot comment on that.

  14. Dikran Marsupial at 06:56 AM on 14 June 2013
    New study by Skeptical Science author finds 100% of atmospheric CO2 rise is man-made

    civil engineer, I did not say that Salby's error was "ridiculous", so it is a fairly poor riposte to the observation of your hubris.  If I am appealing to authority in citing the IPCC report and top carbon cycle experts, then you are undoubtedly doing the same by citing Salby's publications list (how many of his existing papers are on the carbon cycle?).  If Prof. Salby does publish this research, then it is likely that I will, rather reluctantly write a comment paper.

    The fact that you have responded with rhetoric, but no attempt whatsoever to refute the argument presented in my blog article is a good indication that you are not interested in rational scientific debate and are just trolling, so I shall not bother responding to you further.  I suggest others do likewise and DNFTT.

    The fact that the rise in atmospheric CO2 is anthropogenic is known beyond reasonable doubt, and as Fred Singer says, clinging to such obviously incorrect arguments gives skeptics a bad name - but it is your choice.

     

  15. civil egineer at 06:46 AM on 14 June 2013
    New study by Skeptical Science author finds 100% of atmospheric CO2 rise is man-made

    DM,

    I don't find the sks links that convincing and they "suggest hubris". You appeal to authority with your first reply, "top carbon cycle experts, as well as the IPCC report".

    I find that Dr Salby has over 75 publications with nearly 3200 citations. I understand he now has 3 upcomming papers Re Carbon cycle so perhaps you can comment on those as well.

     

    Moderator Response:

    [DB] Any participants wishing to engage civil egineer on Salby should proceed to do so on one of the threads indicated by Dikran.

    This applies to you as well, civil egineer.

  16. Dikran Marsupial at 05:51 AM on 14 June 2013
    New study by Skeptical Science author finds 100% of atmospheric CO2 rise is man-made

    civil engineer, just to clarify, my name is Gavin Cawley (I post pseudonymously, but not anonymously), Prof. Essenhigh wrote the original paper on which mine was a comment.  Mea culpa, the link in the earlier post was to Prof. Essenhigh's original paper, rather than my comment paper, which you can find here.

    Sadly Prof. Salby's argument is also incorrect (I would be genuinely pleased if it were correct) and I and others have written blog posts on his presentations (my article is the first of those listed, and would be a good place to discuss this further):

    Murry Salby's Correlation Conundrum

    Murry Salby finds CO2 rise is natural

    Murry Salby - Confused About The Carbon Cycle

    Salby's ratio

    Humlum et al. make basically the same mistake and another SkS author has published a peer-reviewed comment paper on that one as well, see:

    New study by Skeptical Science author finds 100% of atmospheric CO2 rise is man-made

    Roy Spencer also made a similar error (happily only on his blog and didn't actually publish it), which I discuss here:

    Roys' Risky Regression

    Scientists make mistakes frequently, you are not at the cutting edge of your field if all of your ideas are right, and some errors happen more than once.  Sadly climatology gets a fair amount of media interest, so instead of these errors being quietly forgotten, they end up being discussed in public view.

    Prof. Salby's new talk seems to have some additional material on ice core CO2 proxy data, but the central argument is still that addressed in my earlier SkS post.

  17. civil egineer at 05:36 AM on 14 June 2013
    New study by Skeptical Science author finds 100% of atmospheric CO2 rise is man-made

    (-snip-) Dikran Marsupial,

    I'm curious to know your thoughts on Dr Salby's recent persentation.

    http://www.youtube.com/watch?v=2ROw_cDKwc0&feature=player_embedded

    Moderator Response:

    [DB] It is considered poor form to attempt to call people operating under a pseudonym by what you think that their real name is. Future iterations of this behavior will be moderated out.

    Unless you wish to go by yours...?

  18. UK Secretary of State for the Environment reveals his depth of knowledge of climate change (not!)

    If I understand the implications from El'gygytgyn, the message is that At 300ppm, the world is a different place, at 400ppm a very different place.  The only reason we don't yet experience this difference is the inertia of the climate system.  We will clearly have an ice free Arctic ocean for a day in September in a few years and following that for longer and longer periods.  The Arctic clathrates will be released and so forth. Guy McPherson lists some 10 tipping points we have set in motion.   At best, if we revived all the carbon sinks we have damaged (Alan Savory for instance) and stopped putting new carbon into the atmosphere we might achieve a decrease of 2ppm per year.  We aren't going to do either of these things and 500ppm which at this rate, we will achieve in the middle of the next century is beyond our imaginations.  I know every generation likes to think it is special and special means for the nut cases, the generation that sees Armagedon.  It is just possible that we have succeeded in bringing it on.

  19. Dikran Marsupial at 04:33 AM on 14 June 2013
    An estimate of the consensus project paper search coverage

    Daniel, it is the standard term for the area of research (e.g. International Panel on Climate Change).  The fact that most papers don't take an explicit stance on AGW is itself a useful finding (at least in terms of informing the public debate on climate change).  For a start it refutes the myth that climatologists are promoting AGW in order to secure greater research funding for themselves.  If that were true, all papers would take a stance on AGW somehow.  However scientists are not actually like that, they follow where the science leads, sure they have particular interests, but if reality doesn't fit their current understanding of the physics, they are sensible enough to know that it would be a career limiting move to reject reality.  It also highlights the fact that most climatologists are not actually working directly on attributing warming to AGW, neither of the two climate change related projects I have been involved with were directly concerned with determining the causes of climate change. 

  20. John Russell at 04:27 AM on 14 June 2013
    UK Secretary of State for the Environment reveals his depth of knowledge of climate change (not!)

    I think we're crediting Paterson with more understanding than he actually has. When he referred to the 'Holocene', I think he actually meant to say 'Eocene' (because that's what his GWPF mate Lawson has referred to in the past).  As I wrote in a comment here...

    He's quite right of course that the Arctic was ice free in the Eocene—as was the Antarctic—but to show how irrelevant this meme is he should also have mentioned that our primate ancestors, and all other mammals, were then no bigger than small dogs. Note the line in the link below, "the hot Eocene temperatures favoured smaller animals that were better able to manage the heat": http://en.wikipedia.org/wiki/Eocene (scroll down to 'Fauna').

  21. An estimate of the consensus project paper search coverage

    As a volunteer reviewer, I found very few papers taking a strong position either way.  Most that I reviewed, referred to climate change, without taking a stance as to its cause.  I wonder if choosing the words "climate change" in an abstract is the best metric for this work.

  22. Dikran Marsupial at 03:59 AM on 14 June 2013
    The anthropogenic global warming rate: Is it steady for the last 100 years? Part 2.

    I would like to point out that Prof. Tung has yet again failed to answer a direct question.  It is unsurprising that I had to keep updating my example in order to address Prof. Tungs' repeated misunderstandings, that is the way scientific discussions normally proceed. Had Prof. Tung answered the questions I posed to him, we may actually have reached understanding at some point.  However if we have reached the point where it cannot even be freely acknowledged that a value lies outside a confidence interval, I don't see that there is any likelihood of productive discussion. 

  23. The anthropogenic global warming rate: Is it steady for the last 100 years? Part 2.

    Tung&Zhou 2013 concludes its abstract as follows -"The underlying net anthropogenic warming rate in the industrial era is found to have been steady since 1910 at 0.07–0.08 °C/decade, with superimposed AMO-related ups and downs that included the early 20th century warming, the cooling of the 1960s and 1970s, the accelerated warming of the 1980s and 1990s, and the recent slowing of the warming rates. Quantitatively, the recurrent multidecadal internal variabil ity, often underestimated in attribution studies, accounts for 40% of the observed recent 50-y warming trend." (My emphasis)

    I pointed out @148 above both that half the HadCRUT4 signal remained even after the MLR had been performed and that the "recent slowing of the warming rates" were unchanged when the anthropogenic warming was represented by the QCO2(t) function as presented in Figure 3 of the first part of this post. I was wrong in this last part of my statement. Closer analysis of Figure 2b in the first post (Figure 5b of T&Zh13) shows the temperature record when Sloar, ENSO, Volcanic & AMO signals are accounted for and this clearly demonstrates that the "recent slowing of the warming rates" have indeed changed. The recent slowing has been slowed even more by the performance of the MLR. Also the HadCRUT signal remains essentually unaltered.

    AMO00

  24. The anthropogenic global warming rate: Is it steady for the last 100 years? Part 2.

    Just a short reply to the last few posts: I am trying to move on to other threads, such as responding to Dumb Scientist's post and reviewing other publications on the so-called "thermodynamic argument", but I have been bogged down arguing with Dikran.  I had hoped that it would have been done and then I could move on, but he kept changing his example, making mistakes/typos/inconsistent offsets along the way.  I would write another longer post about my understanding of his thought experiment.  Here I just want to say that he is comparing something, specifically his blue line, which was not part of what our papers were concerned about.  In observation, the total heating over the past 100 years is about 0.7 C, which is the same as what our deduced anthopogenic trend of 0.07 C per decade would give you: 100 years times 0.07 C per 10 years=0.7 C.  The observed total 150 year linear trend and our deduced anthropogenic trend fitted to a linear trend is also the same. There is no controversy about the 100 year or the 150 year linear trends.  Note that the deduced anthropogenic response in our paper is the regressed trend (using whatever the placeholder is in the intermediate step, which could be linear or QCO2) plus the residual, the latter also has a trend.  We called this the adjusted data, which is the original observation minus the influence of ENSO, solar, volcano and AMO.  This adjusted data has a nonlinear trend.  If you know what the true anthropogenic response is, it is this adjusted data (I think it is your greenline) that you should be comparing with the true data (I think it is your red line).  In our paper, we have, to aid visualization, used 150-year, 100-year, 75-year, 50-year and 33-year linear trends to demonstrate that while in the total observed temperature there is an acceleration of trends depending on the interval taken to measure the linear trends, such acceleration has been much reduced for the past 100 years once the AMO and other natural influences have been removed.  The statistical comparison between the true value and the adjusted data is what one should be focused on and I will do that in my rebuttal.  I think by now I understand what Dikran's intent was.

  25. UK Secretary of State for the Environment reveals his depth of knowledge of climate change (not!)

    I've always believed that the most effective rebuttal to the whole Greenland thing is that the part of the world I lived (the U.S. Southwest) underwent a horrific drought at the same time. Now, given the relative populations and economic importance of Greenland (no offense to the inhabitants of Greenland), the effects of a similar level of drought in my part of the world would be devestating.


    And yeah, I learned that on this site.

  26. A short history of carbon emissions and sinks

    Daniel, I must say I'm not great expert on sinks.  That said there have been some studies suggesting that in the boreal forests fungi is playing a major role in sequestration.

    http://phys.org/news/2013-03-fungi-responsible-carbon-sequestration-northern.html

  27. citizenschallenge at 01:56 AM on 14 June 2013
    DenialGate Highlights Heartland's Selective NIPCC Science

    Thanks for posting this information and allowing us to share these articles.

    Reposted at:

    http://citizenschallenge.blogspot.com/2013/06/nipcc-who-are-they.html

     

    cheers, Peter

  28. A short history of carbon emissions and sinks

    Regardign carbon sinks, what can you say about the recent JAXA satellite data.

    http://www.jaxa.jp/press/2012/12/20121205_ibuki_e.html

    It appears that the Northern boreal forests are much greater sinks than the tropical rain forests.

  29. The anthropogenic global warming rate: Is it steady for the last 100 years? Part 2.

    Dr. Tung - I believe that Dikran has shown the results of incorrect fixing/definition of a component in MLR. In the meantime, I would point out that all of this is based on a discussion of a central element in your paper: 

    • Given a signal comprised of multiple components, if you identify (fix) one of those components incorrectly, multiple linear regression against the signal using that fixed component will by definition give incorrect estimates of the other components. 
    • You have used a linear detrending (with support from wavelet analysis of CET for timing, albeit much weaker support for scale and with caveats due to a limited regional dataset) to estimate AMO. There are multiple arguments for other detrendings being more appropriate - such as quadratic, global SST's, or forcings, including papers you yourself have quoted in your support. 
    • Additional information constraining the AMO contribution is available via thermodynamics. While you have spoken to (not to my satisfaction, but I'll agree to disagree on that) Anderson et al 2012, you have not responded WRT Issac Held's or Knutti 2012's discussions on the subject, indicating an upper thermodynamic limit of 25% contribution for all forms of internal variability - higher contributions contradicted by ocean heat content measures. 

    Since your estimate of anthropogenic contributions is directly dependent on your estimate of the timing and scale of the AMO, a scale in conflict with other investigators, thermodynamics and PCA, I (and others commenting on this thread) cannot agree with your conclusions regarding the size of those anthropogenic contributions. 

    Arguing about the fine details of thought experiments, as above, does not change the fact that incorrect fixation of a signal component will lead to incorrect estimates of other components from that signal. And there is considerable evidence indicating just such an incorrect fixation of the AMO component in your work. 

  30. A short history of carbon emissions and sinks

    If you consider land use and biomass emissions together they dominated fossil fuels until as late as the first world war.  But by 2010 fossil fuel emissions were about 8 times greater

  31. A short history of carbon emissions and sinks

    Thanks for the article. I appreciate the overview you get with a 'short history ' style. I hadn't realised that land use was so large a component of the emissions.

    Regarding the 2,000 gigatonnes already emitted, Bill McKibben states that we need to limit emissions from now on to 565 Gt to keep below 2 Deg C. At current emission growth rates it will take 14 years to reach this figure and it's just one fifth of the reserves on the books of the fossil fuel companies. It's a fairly simple and stark equation.

  32. The anthropogenic global warming rate: Is it steady for the last 100 years? Part 2.

    Dikran, there seems to be an editing mishap in your post @160:

    "the average slope of the red line is clearly greater than that of the red, and this is reflected in the confidence interval not containing the true value."

    The average slope of the red line is greater than that of the blue.

     

    Moderator Response:

    [DikranMarsupial] Many thanks, I shall correct the error.

  33. The anthropogenic global warming rate: Is it steady for the last 100 years?

    So Where is Amo?
    The NOAA NCDC temperature data is broken into Land and Ocean as well as for different latitude zones (the zones differing from the GISS zones) so that might show us where he is.
    The graph below shows the NCDC Global data in red (already shown in a post above but here more heavily smoothed to assist the presentation). So is the NCDC Global temperature wobble a signal from the AMO (shown in black)?
    Looking at the Land and Ocean data which is also plotted, the answer is 'No, not unless Amo has a limp'. It would require explanation as to why the dip in AMO in 1910 made such a small impact on Land and big impact on Ocean SST and then in 1970 the dip made a big impact on Land and small impact on Ocean SST.

    The best we can hope is that the red wobble is some big kid with a limp and Amo is hidden behind him. Look! Do I see there the bobble on the top of Amo's hat? Find out in the next thrilling installment of "Where's Amo?"

    AMOb

     

  34. Dikran Marsupial at 19:38 PM on 13 June 2013
    New study by Skeptical Science author finds 100% of atmospheric CO2 rise is man-made

    @civil engineer Calling arguments that have appeared in journal papers written by top carbon cycle experts, as well as the IPCC report "ridiculous" suggests hubris, which is not a good thing in science.

    The mass balance argument, at least stated in its usual form, is not a calculus problem, as the quantites involved represent the actual amounts of carbon that have been moved between reservoirs within a particular timeframe - a year is a common choice.  No calculus is involved.

    Answer me this:

    If during a particular year, net natural emissions are say 2 units and anthropogenic emissions are 2 units and the rise in atmospheric carbon is only 1 unit, where did the missing three units of carbon go?

    Edit: By the way, your initial error is to double count natural fluxes,

    dC/dt= -a*C + N + A

    The net natural response of the carbon cycle is (to a first approximation) proportional to atmospheric CO2 levels, so the natural response is being represented by both -a*C and by N.  If you want differential equation based models, you can find the in my journal paper, and give a reasonable reproduction of a variety of known observations, for instance a constant airborne fraction, and they do they also show that the natural environment is a net carbon sink.

  35. Ari Jokimäki at 19:24 PM on 13 June 2013
    An estimate of the consensus project paper search coverage

    I took a peek to that poptech list once, but I very quickly saw (as would anyone who has gotten familiar with the body of scientific literature on the subject) that it wasn't very good effort. It seems to me that just about any paper could be included to that list when looked at some specific angle. If he would have taken real effort to do it, the list might have been useful at least in some sense. Well, I guess it's also useful now, but only in propaganda sense.

  36. UK Secretary of State for the Environment reveals his depth of knowledge of climate change (not!)

    Tom Curtis,

    Too hand-wavey for me, Tom. The King's Mirror quotation you give I interpret as supporting my earlier point - beyond small scale attempts, there was no significant grain-growing in Norse Greenland. We should not be surprised to find the discarded remnants of these (ultimately) failed attempts.

    The Norse had vegetable gardens, and may well have tried to grow grain in those gardens, but no should be fooled into thinking there were wide fields of corn or barley, or that bread was a staple food, as Patterson's remarks would be interpreted by a listerner unfamiliar with the evidence.

    The difference between us is not about the Norse growing grain but how extensive that was, and how important it was to the community. If the Norse did grow small patches of grain, it was hardly any more significant that provided a small supply of a chieftain's beer or barley bread. For vast majority of the community, hay was the important crop, an absolute necessity to get their domestic animals through the winter.

  37. Dikran Marsupial at 17:57 PM on 13 June 2013
    The anthropogenic global warming rate: Is it steady for the last 100 years? Part 2.

    KK Tung The blue line is the linear trend for the "deduced anthropogenic signal" calculated from your MLR procedure, the green signal is this deduced anthropogenic signal with the residuals of the model added to it.

    If you do not understand what the blue line is, perhaps you need to try to understand the thought experiment first before criticising as your criticisms have consistently demonstrated that you do not understand the point that has been made.  Communicating that point has been made much more difficult by your constistant refusal to give a direct answer to the questions I have posed.  If you give direct answers to these questions it makes it much easier to understand your position, so it is to your advantage to answer them.

    The confidence interval 0.00204 +/- 0.00039 is the interval for the trend of the deduced A plus residual signal.  Does this interval contain the true value 0.00304 representing the trend of the actual A signal?  Yes or No?

  38. A Miss by Myles: Why Professor Allen is wrong to think carbon capture and storage will solve the climate crisis

    Eli would refer Yocta to Rabett Run's take on this that Allen is deeply pessimistic, but too optimistic on the costs of CCS

  39. A Miss by Myles: Why Professor Allen is wrong to think carbon capture and storage will solve the climate crisis

    It is misleading to assume that capture at the generating plant will be simpler and cheaper than air capture because the emissions are not pure CO2.  Both will be expensive in dollars and energy

  40. UK Secretary of State for the Environment reveals his depth of knowledge of climate change (not!)

    shoyemore @15, 1250, the date of the King's Mirror, comes in the tail of the MWP when tempeatures had fallen substantially from the 900-1000 peak.  Nevertheless, even in 1250 the King's Mirror says:

    "As to whether any sort of grain can grow there, my belief is that the
    country draws but little profit from that source. And yet there are men
    among those who are counted the wealthiest and most prominent who have
    tried to sow grain as an experiment; but the great majority in that country
    do not know what bread is, having never seen it."

    In that respect, the cultivation of barley in Greenland would have been similar in extent to its current cultivation.  Given, however, that Greenland would have been warmer in the preceding centuries, it is plausible that it was cultivated more extensively during the early period of norse settlement.  Even so,  

    "Researchers believe the Vikings probably grew barley in small quantities, compared with the large, billowing cornfields we have today, and sowed barley in small enclosures that were no bigger than their ability to irrigate the corn and keep hungry animals out."

    Further, Greenland was never self sufficient in grain.

    Given the comment in the King's Mirror, and the finding, not only of barley grains, but of the "... rachis fragments, the part of the plant that holds the kernel to the spike or ear", which:

    Trigg et al (preceding link) say:

    "While the presence of rachis fragments may merely be a normal component of poorly leaned grain stores, they may also signal that barley was grown nearby . Moreover, the presence of these plant parts among pieces of charred and uncharred dung indicate that the barley may have been eaten by the livestock, which perhaps were allowed to graze on harvested fields or were fed grains and harvesting waste."

    Feeding livestock an imported grain seems unlikely to me.

    In any event, while evidence of cultivation of grains norse settlers may be ambiguous, it favours their having done so on a small scale.  Conseqently, we should not claim the contrary.  I certainly agree, however, that the cultivation was on a small scale indicating that even at its warmest in the MWP, cultivation of grains on the southern tip of Greenland was marginal at best.  

  41. A Miss by Myles: Why Professor Allen is wrong to think carbon capture and storage will solve the climate crisis

    Unfortunately, William, biosequestration will not be sufficient to draw down enough carbon dioxide. A *lot* of the soil carbon rhetoric border on faith and exaggerates the potential to restore carbon in the landscape, for biophysical as well economic reasons, and reforestation carries its own set of risks—the main one being the risk of reversal, particularly in an increasingly hostile climate.

     I say all of this as an advocate for landscape restoration. I believe it has a role, but we will absolutely need industrial-scale CCS. 

     That said, the article is spot on: Myles Allen is way out of his depth here. 

     A plea/cry of pain to the editors of Skeptical Science: a hyphen is not a dash! The little bitty hyphens drive me nuts—use dashes!

    Moderator Response:

    [AS] Thanks! I agree about the hyphens/em-dashes. I'll change them. It was a revelation to me when I discovered that in MS Word you can enter an em-dash with ctrl-alt-minus sign (on the number pad). But in our comment and blog editor windows you have to enter them as special characters—and that's a pain, so we forget some. I hope our critics forgive me for not marking these changes as strike-throughs. ;^)

  42. A Miss by Myles: Why Professor Allen is wrong to think carbon capture and storage will solve the climate crisis

    Lacking option of using biomass residues as source of fuel, combined with carbon capture to provide CO2 for enhanced growth for algea and food products. Also rest-carbon could be stored in soil for 40-100 years (as soil ammendment).

    Instead of burning residues, letting it rot away, one saves on both sides: no rotting material providing xx tons of CO2 and direct reuse of the CO2. If I am not mistaken currently CO2 for industrial use in made from fossil. Any syngas producing power station can provide industrial process enough concenrated CO2 to make enough pure CO2 for industrial use.

  43. The anthropogenic global warming rate: Is it steady for the last 100 years? Part 2.

    Dikran: I am not even sure what your blue line is.  How can I then "come to the conclusion that it is the underestimate of the signal in red"?  I thought we are supposed to be comparing the adjusted data (green curve), which is the regressed signal with the residual added back following our procedure in our paper (I assume you were following our procedure), against the true signal which is the red line. 

    The offset is relevant because once you corrected an inconsistent offset of the green vs the red, the two are much closer in your new figure compared to your old.

  44. UK Secretary of State for the Environment reveals his depth of knowledge of climate change (not!)

    Correction to previous post - " I keep urging our Australian conservatives, who continue giving climate science denial and obstructionism their imprimatur of respectability and legitimacy whilst simultaneously declaring their confidence in mainstream climate science to ditch that position; is this a taste of what we will get when we do get a conservative government; public declarations of commitment to international agreements that gloss over a complete lack of understanding of it's seriousness?"

  45. UK Secretary of State for the Environment reveals his depth of knowledge of climate change (not!)

    So the Paterson has got denier talking points so thoroughly internalised he can bring them out  fluently and effortlessly whilst actual mainstream climate science looks to be something he chooses not to be well acquainted with.

     From an Environment Secretary of State who is part of a globally influential government that supposedly accepts the validity of climate science it is deeply dismaying.

    I keep urging our Australian conservatives, who continue giving climate science denial and obstructionism their imprimatur of respectability and legitimacy whilst simultaneously declaring their confidence in mainstream climate science; is this a taste of what we will get when we do get a conservative government; public declarations of commitment to international agreements that gloss over a complete lack of understanding of it's seriousness?

    Given how much easier compromising a policy to the point of pointlessness is compared to developing serious policy and pushing it through with determination, this UK example doesn't bode well for Australia's part in future efforts to avoid catastrophic climate change.

  46. civil egineer at 07:30 AM on 13 June 2013
    New study by Skeptical Science author finds 100% of atmospheric CO2 rise is man-made

    Aren't you applying algebra to a calculus problem?

    Suppose atmospheric CO2 labelled “C” progresses according to the differential equation

    dC/dt= -a*C + N + A

    where ‘A’ is an inverse time constant. The first term is the action of “natural” sinks, which respond to the total level of C in the atmosphere. The second term is natural forcing. The third term is anthropogenic forcing.

    The rate of change of C is less than A. Thus,

    -a*C+ N .LT. zero

    The ridiculous pseudo-mass balance argument then says, voila! Nature is a net sink.

    But, the solution of the above equation is the convolution integral of N + A with the exponential term exp(-a*t). InLaplaceoperator form

    C(s) = (1/(s+a)) * (N(s) + A(s))

    The left side of the above inequality then becomes

    -a*C+ N = (s*N(s) – a*A(s)) / (s + a)

    Thus,

    [dN/dt - a*A] .LT. zero

  47. Dikran Marsupial at 06:44 AM on 13 June 2013
    The anthropogenic global warming rate: Is it steady for the last 100 years? Part 2.

    Prof Tung. I said quite explicitly that there was no error.  The attribution of Y to A depends on the identification of the correct value for the regression coefficients, which gives the GRADIENT of the signals, and the offset is irrelevant.

    The confidence interval defined by your MLR procedure does not contain the true value, and therefore the MLR procedure is demonstrably unreliable.

    I don't understand how anyone could look at the plot shown in my post #158 and come to the conclusion that the blue line is not an under-estimate of the signal shown in red, the average slope of the red line is clearly greater than that of the blue, and this is reflected in the confidence interval not containing the true value.

    Moderator Response:

    [Dirkan Marsupial] Error spotted by Leto corrected.

  48. UK Secretary of State for the Environment reveals his depth of knowledge of climate change (not!)

    Just found this Huffington article from last year:

    http://www.huffingtonpost.co.uk/2012/10/27/windfarms-backed-by-environment-secretary-owen-paterson_n_2029079.html

    He seems to say quite similar things in that interview, except he adds 'There are all sorts of other things that affect climate change, like the sun.'

    For the record, I don't think straight trees is a good sign as to whether there is enough wind for a wind farm! (as Paterson seems to suggest it is).

  49. The anthropogenic global warming rate: Is it steady for the last 100 years? Part 2.

    In reply to Dikran Marsupial in post 158: Although you did not admit it explicitly here, you seem to agree that there was an error, at least an inconsistency, in how you offset the red curve and the blue and green curves.  In your post 123, you used your last figure, with an inconsistent offset,  to show that the true A is above the blue and the green, leading to your conclusion:

    "The deduced anthropogenic trend is less than the true value, and the true value does not lie within the confidence interval."

    You may have other evidence that you did not show for this conclusion (and I don't quite understand your definition of the CI as from the gradient of the blue line), but your post 123 used only an erroneous figure to draw this visual conclusion.  The corrected figure in your post 158 now shows that it is no longer visually obvious. In fact the true A (the redl ine) lies within the deduced adjusted data (green curve), which you labelled as deduced trend plus residual.  I don't know what your blue curve is. It was not what we used.  It appears to be a 150 year trendIf that is what it is, then it seems to be doing fine compared to the 150 year linear trend of true A.  Please let me know if my understand is correct. I want to know what I am arguing against.

    I will try later to address the issue why a deterministic example is trivial and why it is irrelevant as an example to argue your point.  I just don't want to argue against an example with minor errors that you could correct easily.

     

  50. UK Secretary of State for the Environment reveals his depth of knowledge of climate change (not!)

    I'm surprised Paterson didn't mention Romans growing grapes and producing wine in Britain. That would have made a perfect score.

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