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Comments 46551 to 46600:

  1. Making Sense of Sensitivity … and Keeping It in Perspective

    "Notice that it is for all intents and purposes, in that small range, linear." You're right, but the global climate is so complex. It's still not sitting well with me so I decided to try and derive it myself. Take the following with a grain of salt. I might have done something wrong or interpreted something wrong.

    Anyway, using the energy balance...

    Power in = (1-α)πR2F0

    Power out = 4πR2ϵσT4, where ϵ is the emessivity

    Thus, F = ϵσT4, where F = (1-α)F0/4

    Thus, T=[F/(ϵσ)]1/4

    The total derivative is: dT/dF = δT/δF+δT/δϵ*dϵ/dF

    substituting and simplifying:

    dT/dF = T/(4F)-T/(4ϵ)*dϵ/dF, where the term T/(4ϵ)*dϵ/dF is from feedbacks.

    Thus, the linear approximation for climate sensitivity is k ≈ 4*dT/dF ≈ T/F.

    With this linear approximation we're assuming that for small changes in temp the term T/(4ϵ)*dϵ/dF is almost constant or negligible. Feedbacks aren't negligible so we're arguing it's almost constant.Thus, we're assuming

    dϵ/dF ≈ C*ϵ/T, where C is a constant. I still don't like this approximation. I guess I have to do more reading. Again I might have done something wrong or interpreted something wrong so take the stuff above with a grain of salt. Thanks

  2. Antarctic Octopus Living Testament To Global Warming

    When I was reading Twenty Thousand Leagues Under the Sea as a child, I thought "Interesting but completely our of reality nonsense" because Jules Verne did not know that Antarctica was a continent rather than ice shlf like arctic. BTW, Verne could have been ignorant, because even back then (mid-end of XIX century) the adventurers could have known about antarctic mountains.
    Anyway, that has now changed: Nautilus could have swam under the antarctic ice just like octopuses did, if the action have taken place in Eemian...

  3. Jeffrey Davis at 11:17 AM on 11 April 2013
    Real Skepticism About the New Marcott 'Hockey Stick'

    McIntyre's work is rhetorical rather than scientific. Hence the innuendoes and sarcasm.

  4. Real Skepticism About the New Marcott 'Hockey Stick'

    Tom that is a very interesting point. I asked around here and no 8.2ka event known NZ circles but dating is lousy. Suppose you just used Alantic-influence proxies. If the spike doesnt show with them using Marcott/Tamino's methods you must definitely conclude that the method isnt capable of resolving such spikes.

  5. Rob Honeycutt at 10:41 AM on 11 April 2013
    Real Skepticism About the New Marcott 'Hockey Stick'

    Tom @ 21...  "Such errors provide "skeptics" an opportunity to point to a mistake..."

    You know, it seems to me, that's something that can never end.  Science is iterative.  It's never perfect.  There is always something more to understand, always a better and more accurate way to look at things.  

    I keep getting the sense that the "skeptics" prey on this essential element of the scientific process in order to try and undermine it.  Any real skeptic would look at a paper like Marcott and find ways that improve it by being skeptical.  McIntyre and his ilk do the same thing, but in order to try to tear down other scientists and their work.

  6. Real Skepticism About the New Marcott 'Hockey Stick'

    The point isnt whether McIntyre is a competent statician or not. It's what he does with it. Mostly what he has done is to draw attention aware from the main points of the paper to a sideshow. However the main point of the article is that the statistics were used simply to give people a reason to dismiss the paper whereas Tamino took the criticism on board and explored the effect and what it would do for the conclusions. Tamino's stuff advances science and could be worth publishing. McIntyre? All you seem to get sniping from sidelines, innuendo about improprietary and nothing published since M&M. I'd say put up or shut up.

  7. Real Skepticism About the New Marcott 'Hockey Stick'

    Ray - I've read through a number of the McIntyre discussions on Marcott, and (personal opinion only) have found them to be a mix of cherry-picks and arguments in detail while ignoring the larger picture. With language like "Marcottian uptricks upticks" and the like, McIntyre appears to be taking more an ideological approach than a scientific one. 

    I've also seen numerous statistical mistakes made by McIntyre, such as not knowing how to judge principal component weighting or deal with normalization (such as incorrectly selecting significant components, giving unsupported results), both in his attacks on Mann et al and Lewandowsky et al - I have not been impressed. 

    Your mileage may vary, but I don't find his work a useful contribution. 

  8. Real Skepticism About the New Marcott 'Hockey Stick'

    KR

     

    There are a couple of current pieces on Climate Audit looking in some detail at the proxies used in the Marcott paper and making some comparisons between these and other similar proxcies.  The language used isn't hysterical and the conclusions drawn don't seem overly comtentious. McIntyre, whatever his shortcomings, perceived or otherwise, is a competent statistician and there are points made, which, to me at least, give a wider perspective on the pros and cons of the various proxies that used in climate science.

  9. Real Skepticism About the New Marcott 'Hockey Stick'

    As has previously been discussed, the 8.2 Kya event was a very significant cooling event associated with the suden release of large volumes of melt water into the North Atlantic.  The volume of melt water released may have raised sea levels by as much as 1.2 meters.  The effect in the North Atlantic was drastic, dropping regional temperatures by as much as 3 degrees C.  The fall in temperatures is detectable in Soreq Cave (in Palestine) and in Kilamanjaro Ice cores.  It is unclear whether it is detectable further afield.  There are large negative excursions within age uncertainty in Antarctic Ice cores.  The temperature excursion is large enough to effect the global mean surfacte temperature even if regionally confined.  If, as is possible, it was a global excursion, it would have resulted in a fall, then recovery of global mean temperature of about 1 degree C.

    The significance of this is that it hardly registers on the Marcott et all reconstruction.  It barely registers even on Tamino's emulation, which is more sensitive to short term variations.  If you look at figure 2, just prior to 6000 BCE there is a sharp decline.  That is followed by a short up and down blip, followed by a general rise.  Shortly after the start of that general rise there is a very brief downward blip.  That blip is the 8.2 Kya event as it shows up in Tamino's version of the Marcott reconstruction.

    This specific example shows, again, that Tamino's test was not adequate to support his claims, as repeated in the main post above.

  10. Real Skepticism About the New Marcott 'Hockey Stick'

    Incidentally, the count of 'skeptic' posts terribly upset about this paper is up to at least 26 on WUWT, and 14 at ClimateAudit. Apparently they find the outlines of Holocene temperatures, compared to where we're going now, very threatening in some fashion.

  11. Real Skepticism About the New Marcott 'Hockey Stick'

    Tom Curtis - And as already discussed, we have sufficient proxy evidence (completely aside from the Marcott reconstruction and statistics) indicating the 8.2 Ka event and the drop in global temperatures then, an excursion lasting only a few centuries. As I noted here, there is no such support (nor physical mechanism) for any upward spike in temperatures during the Holocene of the nature and scale seen in current warming. 

    You certainly do have a point re: Marcott and the 8.2 Ka event - I had not carefully considered the timeline in previous remarks - but there's no evidence of 0.9 C warming spikes during the Holocene. 

    That's from the full body of evidence - completely aside from the Marcott et al time resolution, there is no indication of such a spike in proxy data that shows the 8.2 event. Hence arguments based upon "a spike might have been missed" are inconsistent with that body of evidence. And claims about such spikes are IMO the result of arguing about only one paper, when there is a great deal more data available contradicting such claims. 

    [ Not to mention that current warming will not be a short 'spike' - thousands of years will be required to draw down the CO2 we've put up in the last 150 years. And therefore claims about Holocene spikes too short to show in Marcott are irrelevant. ]

    In that regard I find the 'spike' arguments seen from Watts, McIntyre, and the like to be in essence cherry-picking and red herrings; arguing about one set of data (which has its pluses, minuses, and uncertainties, and which definitely will be discussed/elaborated upon in future work) by making hypothetic claims clearly contradicted by the rest of the information available. I'm rather appalled at the time wasted on this nonsensical side-line. 

  12. Real Skepticism About the New Marcott 'Hockey Stick'

    KR @16, as we have already discussed, the 8.2 Kya cooling event, which was large, wide spread and possibly global, does not show up in the Marcott et al reconstruction.  Or more precisely, it shows up as a 0.01 C dip in the general rising pattern at that time (in the reconstruction).  That dip is too small to be seen in standard representations of the reconstruction.

  13. Real Skepticism About the New Marcott 'Hockey Stick'

    Paul R Price @20, much as I appreciate the effort, your graph contradicts the data in Marcot et al.  Specifically, it ignores the fact that the mean reconstruction is heavilly smoothed by Marcott et al's proceedure, and that it therefore conceals probable events with higher temperatures in the past.  For example, you say that current temperatures exceed any experienced in the last 125,000 years.  Marcott et al, in contrast say that between 18 and 28% of Holocene temperatures exceed modern temperatures.  You place a line which even crosses the 1 sigma error bar with the label, "Temperatures unknown to human civilization".  In fact, if we are to take Marcott et al's figure 3 seriously, human civilization has experienced temperatures up to 0.5 C greater than current temperatures in the interval between 6000 and 2000 BCE, albeit for less than 5% of that time.

    These may seem like quibbling errors to you.  They are not.  Such errors provide "skeptics" an opportunity to point to a mistake, for the benefit of themselves or their friends.  Having found such a mistake, it is then used as an excuse to switch their minds of and not consider the true ramifications, which apart from these errors you have admirably illustrated.

  14. Antarctic Octopus Living Testament To Global Warming

    # 9 william

    One has to account for the change in MSL between the Eemian and the Holocene. Eemian GAT was ~1C above the late Holocene but mean sea level was ~5m higher.

  15. Real Skepticism About the New Marcott 'Hockey Stick'

    Dana,

    Thanks for the summary of Marcott reaction, great point about what it says about real vs. false skepticism.

    Inspired the post by Jos Hagelaars here is a poster annotated version of Hagelaars' Marcott graphic I have put together with temperature bands indicating human history and with last dates to constrain warming to different temperatures from Stocker (2012). 

    If a bit cluttered but is intended as a poster to convey science to policy types as another attempt to convey the enormity of what is now occurring. Any constructive comments or corrections welcome, especially if there are other strong references in contrast to Stocker for peaking or carbon budget exhaustion dates.

    Paul

    Moderator Response:

    [TD] Thanks, Paul!  A related SkS post is The Y-Axis of Evil.

  16. Land Surface Warming Confirmed Independently Without Land Station Data

    What strikes me is how different the trends are in some parts of the globe between the two maps. Does this imply that some areas have a huge warm or cool bias in the temperature record? Seems most unlikley to me. So either there are errors in the non temperature data at the "local" level or the model is ok in aggregate but error prone at the detail level or???

  17. Real Skepticism About the New Marcott 'Hockey Stick'

    Bob Loblaw - Good point.

    Lars Karlsson - You're correct, some 'skeptics' might argue those points. And as I stated, I would find such arguments rather silly. They could use roughly the same arguments from unsupported possibilities to make claims about unicorns, after all.

  18. Rob Honeycutt at 06:24 AM on 11 April 2013
    Real Skepticism About the New Marcott 'Hockey Stick'

    Lars... The problem there is, what ever magical unknown forcing that might have occurred has to also square with very well known changes in forcing we see today. And those forcings have to square with climate changes seen in the deep past as well.

    The holocene is not some isolated segment of time in Earth's history that had different forcings and CS than the rest of Earth's history and the present.

    It's just odd to me how hard it is for some people to accept that the overwhelming body of scientific research is mostly likely correct.

  19. Antarctic Octopus Living Testament To Global Warming

    I wonder if the scientists have taken into account the "floating ice" consideration.  For instance, if there is a basin with a bottom is 100m below sea level filled with ice, all the ice up to sea level and approximately 10 meters above sea level will have no effect on sea level if it melts.  Only the ice above 10m above sea level will cause a rise in sea level if it melts.

  20. Real Skepticism About the New Marcott 'Hockey Stick'

    KR: I took Lars' comment as a prediction of what we'de hear from the fake skeptics, rather than an expression of his own beliefs, but it's hard to read tone into the printed word.

    ...and the "plausible physical mechanism" is called "pixie dust" (AKA "natural cycles").

  21. Real Skepticism About the New Marcott 'Hockey Stick'

    Lars Karlsson - Just to make certain I have your points straight:

    According to your post, large scale temperature rises in the past, which we have no evidence for (despite proxy evidence showing events like the 8.2 Kya cooling, which should indicate our ability to see such changes), nor any plausible physical mechanism for such a spike, involving forcings that we somehow haven't detected over the last century (the most measured period in human history), are sufficiently possible for you to argue against known radiative physics (the CO2 contribution) and/or that because of these unseen forcings you feel the climate sensitivity might be low?

    I find myself oddly unconvinced...

  22. Antarctic Octopus Living Testament To Global Warming

    Yes, the last interglacial, the Eemian (about 120-130,000 years ago), was thought to be slightly warmer than present. This was due to changes in Earth's orbit and rotational tilt (obliquity) which allowed more sunlight to reach Earth's surface - especially the Northern Hemisphere. See this SkS series of posts on the last interglacial.

  23. Steve Metzler at 05:46 AM on 11 April 2013
    Real Skepticism About the New Marcott 'Hockey Stick'

    Lars, with all due respect... you're bending over so far backwards there that... well, you know :-)

  24. Antarctic Octopus Living Testament To Global Warming

    This must be evidence that past interglacials could have been warmer or of longer in duration or both then the one we are experiencing today.  The causes of these past interglacials must have all been of natural origin. 

  25. Lars Karlsson at 04:22 AM on 11 April 2013
    Real Skepticism About the New Marcott 'Hockey Stick'

    If some "skeptic" has actually thought about the implications of more variability in the past, he/she may have thought along the following lines.

    Larger temperature variations in the past does not necessarily imply a higher climate sensitivity. They might instead indicate some stronger natural forcings, which might in principle have gone undetected or unaccounted for during the last century, and these forcings may have then contributed singificantly to the warning in the last 100 years in which case the contribution from CO2 would be less and hence climate sensitivity might be lower.

    So this leaves a rather slim but still existing possibility that larger temperature variations in the past and a low climate sensitivity can both be true at the same time. 

  26. 2013 SkS Weekly Digest #14

    Archie, has global warming plateaud? (two 16-year trends that overlap, one .3C per decade; the other .0875C per decade; and the climate-scale trend (37 years): .165C per decade, just under the expected rate of warming)

    What do you think?  Respond on the appropriate thread.

    Moderator Response:

    [TD] Archie, there best thread for that particular issue is "Human activity continues to warm the planet over the past 16 years". For the more general conversation you started, use "Making Sense of Sensitivity … and Keeping It in Perspective." No matter where you post, you can see all replies by doing what most regular readers do: Watch the overall Recent Comments list, which you can get to by clicking the "Comments" link in the blue bar at the top of every Skeptical Science page.

  27. Antarctic Octopus Living Testament To Global Warming

    interesting study, but is their life cycle well understood? i guess so for the study's been published.

    the two large gorges crossing the transantarctic mountains could still have had an ice shelf over them of course, for the extensive snowfalls on the (pen)insula mountains and south in transarctic montains. and the ross sheet might have been attached to the bottom for the rebound. but ok, +4 - +6 meters of global sea level rise from melt is still plenty. pig, thwaites and ronne to go if not greenland, and other way around. filchner will stay for a long time (origins partly on eais).  

    off topic (lame joke), there has been some rumours of ocean's fourteen movie, but i think oceans 13m ASL was bad enough.

  28. Real Skepticism About the New Marcott 'Hockey Stick'

    Eli @12 - good point, have updated the post to give Nick Stokes credit for his genuine skepticism as well.

    Another issue which seem to be allulded to in the comments here involves confused claims that Marcott spliced the instrumental temp record onto his proxy data set.  The study did not do that.  They did compare the 0.8°C warming in the instrumental temperature record over the past century to the cooling of similar magnitude over the past 5,000 years in their proxy data set, which is certainly a valid and useful thing to do.

  29. 2013 SkS Weekly Digest #14

    archie lever, there is a Skeptical Science analysis of that Economist article.

  30. Philippe Chantreau at 01:02 AM on 11 April 2013
    Trillions of Dollars are Pumped into our Fossil Fuel Addiction Every Year

    Kevin's "The low income people spend a higher percentage of income on energy."

    That's silly. Low income people spend a higher percentage of income on almost anything they buy, compared to even slightly higher income people. The immense majority of products and services aren't offered on an income based scale sliding scale.

    The only way for low income people to make that adjustment is to opt for cheaper solutions (i.e. rent a 2 bedroom appt instead of owning a 4 bedroom 2000 sq.ft house) or to consume less. Wherever someone lives, there is no cheaper solution for electricity and fuel, as price is decided by the utility and gas prices are pretty consistent by region.

    Income disparities are such that for many items, no reduction in the quantity consumed will bring the percentage on par. In the US, the kind of person who can drive a brand new Lexus will spend a far smaller percentage of their income on gas than the person driving a used Chevy, except if the latter drives around the neighborhood a couple of times a week.

  31. Real Skepticism About the New Marcott 'Hockey Stick'

    Now some, including Eli to be sure, might think you should give Nick Stokes more credit for his posts on Moyhu and on CA.  Nick might run a designer botique, but he is always worth reading on these things.

  32. 2013 SkS Weekly Digest #14

    archie lever @3, warming has "plateaued" at a rate of rise greater than the twentieth century average (GISTemp).  That little fact the economist probably forgot to mention.  Further, paleo studies of climate sensitivity continue to show climate sensitivity greater than 3 C.  Studies of temperature increase in the last century and some studies of the increase since the LGM show lower sensitivity; but the latter depend on a controversially high finding of LGM temperatures and the former are very noisy.  So perhaps, and hopefully they are right about the climate sensitivity - but that is not a conclusion that can be drawn from the full range of recent studies.

  33. Trillions of Dollars are Pumped into our Fossil Fuel Addiction Every Year

    Kevin @39, apparently it is your intended stragegy to argue against a policy because half the policy will have consequences that the full policy does not.  That makes your arguments trolling in any man's language.  Given that, and that you have been comprehensively refuted, there seems little point in further responding to you.

  34. 2013 SkS Weekly Digest #14

    According to last week's 'Economist' report warming has plateaued and climate sensitivity is most likely lower than the 3 degreesC for doubling CO2.  Any comment on this?

  35. Trillions of Dollars are Pumped into our Fossil Fuel Addiction Every Year

    Composer99 @37, the 2009 Census data does show that households in the North-East spend, on average, 22.5% more on utilities than do households in the west.  The next most expensive region after the North-East is the Mid-West, then South, then West.  The increase is almost entirely due to increased demand for electricity, gas and fuel oil so it is a reasonable conjecture that the increased energy use is due to heating requirements.

    That increase is partly compensated because the West and particularly the South spend far more on gasoline than do the Mid-West and the North-East (particularly).  Never-the-less, a carbon tax would slightly favour the warmer regions of the US over the colder in the short term.  (Of course, longer term heating bills in the north will fall, while cooling bills in the south will rise.)

  36. Trillions of Dollars are Pumped into our Fossil Fuel Addiction Every Year

    Composer 99,

    I missed Houston.  Minneapolis also jumps out as an anomoly.  However, the rest remains.  Also, keep in mind that cost of utilities is not definitively amount of utilities, as the repective price of utilities is not listed.

  37. Trillions of Dollars are Pumped into our Fossil Fuel Addiction Every Year

    Composer 99,

    The evidence that Tom Curtis presents straightforwardly shows that expenditure increases, in absolute terms, with income in the US. It then follows that, contrary to your assertion, a per capita or otherwise income-neutral carbon dividend or rebate will disproportionately benefit lower income individuals & families - indeed, all the more so if they spend a higher proportion of their income on energy.

    Think it through.  The low income people spend a higher percentage of income on energy.  The proposal is to "tax" carbon, effectively raising the price of energy.  This will push the percentage up that lower income people spend on energy, not down.  How that tax revenue then gets distributed through lower income tax rates (as in the example presented) is a different issue. 

     

  38. Trillions of Dollars are Pumped into our Fossil Fuel Addiction Every Year

    Kevin @36, assuming for ease of calculation that all people within the same income bracket pay the same amount on utilities, then the maximum percentage payment for the 70-79K bracket is 4.9%, not 5.58%.  On the same basis, the minimum percentage payment in the 120-150K bracket is 2.76% while the maximum is 3.47% so both of your figures are out.

    More importantly, you continue to ignore the fact that you are criticizing a proposal compensation in the form of a flat rate per capita dividend.  The people in the 70-79K bracket pay approximately $3500 per annum on utilities.  The people in the 120-150 K bracket pay approximately $4200 per annum on utilities.  So, first, 3500 < 4200 so the people in the lower income bracket will pay less carbon tax than the people in the higher income bracket.  Further, because they are paying less and recieving the same amount back, they will be relatively better of after the carbon tax plus dividend than the people in the higher bracket.

    Resorting to percentages to confuse the issue is the lowest form of legerdemain.  It ignores the fact that the flat rate dividend represents a far greater percentage of low incomes than it does of high incomes. 

  39. Real Skepticism About the New Marcott 'Hockey Stick'

    Correction: the climate was relatively stable in the past 10,000+ years. That does not necessarily mean that it is still stable today. Perhaps that past stability had to do with the fact that ecosystems were relatively intact then. Currently, we have destroyed half the forests on land and overfished and destroyed three-quarters of the marine fisheries. Will the climate remain relatively stable as we merrily continue with the destruction of ecosystems at an exponentially growing pace, mainly to satiate the appetites of the rich one-third of humanity? That question cannot be answered based on simple extrapolations from the past.

  40. Trillions of Dollars are Pumped into our Fossil Fuel Addiction Every Year

    Kevin:

    The evidence that Tom Curtis presents straightforwardly shows that expenditure increases, in absolute terms, with income in the US. It then follows that, contrary to your assertion, a per capita or otherwise income-neutral carbon dividend or rebate will disproportionately benefit lower income individuals & families - indeed, all the more so if they spend a higher proportion of their income on energy.

    How does this prove any point you have sought to make on this thread? How does it tie into the discussion in the OP of reducing subsidies to fossil fuel production? It seems to me to be contradictory to the primary claims you have made on this thread.

    You have also claimed, without substantiation, that the regional energy consumption patterns show that "it does stand up that the colder the city you live in, the more you will spend on energy."

    Whether or not this is the case, you cannot conclude so based solely on your comments: all you have is a correlation and no analysis showing that it fits together the way you want it to.

    At any rate, just looking at the data, one notes that the regional breakdown shows that the largest expenditures, by region, of utility & fuels (in the housing category) and gasoline & motor oil (in the transportation category), occurs in the Housten-Galveston-Brazoria region. For the reasons I have outlined above this is not a conclusive blow against the notion that expenditures on energy relate to climate of one's residence, but if you wish to support the relationship you are claiming exists, you must take it into account in your analysis.

  41. Real Skepticism About the New Marcott 'Hockey Stick'

    With respect to possible spikes in the Holocene record, as claimed by 'skeptics' looking for alternative explanations for current warming: It's worth noting that there is a 200-400 year spike that we have significant evidence for - the 8.2 Kya decrease in temperatures, possibly caused by meltwater from the Laurentide ice sheet. This shows up in ice cores, sediments, and changes in sea level. 

    On the other hand, we have no evidence for major warm spikes in the Holocene, certainly nothing like the ~0.9 C current warming, nor any plausible natural mechanisms that could cause one. Claims to the contrary are, IMO, a mix of claiming "it's a natural cycle, "it's not us" and simple denial of the greenhouse effect. 

  42. Real Skepticism About the New Marcott 'Hockey Stick'

    (1) I have added a comment (awaiting moderation) to the Tamino blog post.

    (2) I don't find anything in the Marcott analysis to give me reasons to be optimistic about the future. First, we have rather good reasons to believe that nothing like the last two hundred years (approximately) of climate history has happened in the last several million years. Second, despite all that we don't know about the fine details of the Earth's climate system, I think we have a rather good general understanding of the role of greenhouse gases (carbon-based gases in particular) in controlling temperature and the carbon cycling in the atmosphere-hydrosphere-biosphere system with slow but more or less steady draining to the lithosphere and occasional brief small releases of carbon from the lithosphere (principally volcanic releases) to the active atmosphere-hydrosphere-biosphere climate system. Third, as I understand the Pleistocene ice core data, the general picture is that CH4 was the initial amplifier of the Milankovich warming stimulus with CO2 being the subsequent "enforcer" of the warming periods. Fourth, about two hundred years ago, humans began a massive transfer of carbon from the lithosphere to the atmosphere-hydrosphere-biosphere system. So far as I know, this massive injection of lithospheric carbon into the climate system is unprecedented in recent history (recent meaning the last few million years). To me, it seems somewhat similar to the volcanic transfer of lithospheric carbon that preceded the Paleocene-Eocene Thermal Maximum. And we only need to continue business as usual for a few more decades to achieve in about three hundred years something similar to the change in atmospheric CO2 concentrations that occurred over about ten thousand years 50 million years ago.

    Given the above, I don't think we really have sufficient historical information to accurately predict the outcome of a really new climate ball game. My main point is that it is not simply that we have increased the carbon-based greenhouse gases in the atmosphere (and dissolved in the hydrosphere) but it is most significant where we have taken that carbon from.

  43. Real Skepticism About the New Marcott 'Hockey Stick'

    MartinG @3: "Nobody, not even ”contrarians” disputes that surface temperatures have risen in the last 100 years"

    That just isn't true. Even a US senator claims that nobody disagrees that we are in a cold period. A short read on contrarian blogs shows that they throw doubt on anything they don't like, including the modern temperature record.

  44. Real Skepticism About the New Marcott 'Hockey Stick'

    CBDunkerson @6,

    Tamino explains here why 'magical temperature spikes' of last century's magnitude could not go undetected in Marcott 2013 reconstruction.

    To those who doubt the possibility of detecting the high frequency periodic signal with lower frequency sampling, just think what Fourier transform can do for you. Look here for the simplest example.

    I agree with Tamino that Marcott 2013 signal proves conclusively their main result (that last century warming trend is unprecedented) regardeless of logical explanations.

  45. Trillions of Dollars are Pumped into our Fossil Fuel Addiction Every Year

    Tom Curtis,

    It is noteworthy that household expenditure on energy as a percentage of income declines with increasing wealth; so a dividend based on taxable income would make the poor worse of - but that would be a political decision to do so, and is not what is being proposed.

    It is further noteworthy that household expenditure on rates including electricity never rises above 4.5% of household income, showing that doom and gloom stories about the impacts of a carbon tax on the poor are works of fiction.

    From the tables in the article you supplied, the percent income spent on "utilities" for the 70 79K bracket is 5.58%.  The percent income spent by the 120 - 150K bracket goes down to 3.77%.  This just proves my point.  The primary need for heating / cooling, with some elasticity for wealth thrown in - I'll grant you the elasticity is more than I anticipated.

    As to never rising above 4.5%, the figures you supplied also included water, so whether the 5.58% is less than 4.5% once water is removed is impossible to tell.

     

    Scaddenp,

    If you look at the data that Tom Curtis supplied, you will notice that the highest consumers were in cities like Philadelphia, New York, and Boston, and the least consuming cities were San Diego, and San Franscisco, so it does stand up that the colder the city you live in, the more you will spend on energy.

  46. Real Skepticism About the New Marcott 'Hockey Stick'

    The thing which tickles me about the whole Marcott uproar is that the graph isn't really 'new'. Past studies had shown the same basic shape... which is why the Shakun reconstruction can be lined up with Marcott in the first graph in the post above. The Marcott study has just narrowed the uncertainty ranges. Just as subsequent versions of the original 'hockey stick' time period have given us an increasingly clear image there.

    There will inevitably be more analyses of the Marcott (and Shakun) time periods which will continue to give us better and better data. The 'skeptics' are now clinging to a ridiculous belief in 'magical temperature spikes'... there is some disagreement over whether the Marcott study conclusively disproves that or not, but it really doesn't matter because there is no logical explanation for how they could exist in the first place.

    The BEST surface temperature study had an interesting approach of including even very fragmentary temperature records and correcting for outliers. I expect we'll eventually see something like that applied to the various proxy records... so you'd have the widely spaced proxies from Shakun and Marcott in the same study with annual proxies from Mann and other ~1400 year 'hockey sticks' and the even more detailed proxies used to match the instrumental record in Anderson. Different proxies over different time periods, but they can all be woven together to create a single record of equal or greater accuracy than the individual studies.

  47. 2013 SkS Weekly Digest #14

    Actually, Delingpole has been a special kind of crazy for a long time. He just isn't as well known as Monckton.

    That said, I've never been comfortable with the fact that there have been calls for a 'climate Nuremberg' going the other way too. People should be held accountable for lies, slander, and destructive deceptions, but let's leave the Nazis out of it.

  48. Antarctic Octopus Living Testament To Global Warming

    Huh. I knew a lot of Antarctica was below sea level because of the ice pressing down on it, but I'm surprised to see large contiguous swathes like that. This would suggest to me that if the mass of ice on top melts enough that it would no longer weigh enough to push the bottom ice down to the land surface large portions of the ice sheet could just 'pop' free from buoyancy and float away. Not going to happen any time soon, but significant portions of the Antarctic ice may wind up being lost through export rather than in situ melting.

  49. Real Skepticism About the New Marcott 'Hockey Stick'

    MartinG @3.
    It is true that almost all contrarians don't dispute the surface temperature record but there are plenty who dispute its validity as a true record of surface temperature.


    As for your assertions that if the end point of the Marcot curve were at an earlier time would yield some sort of 'anti-hockeystick', this is entirely wrong. The Marcot curve does still have an uptick all of its own, even after the 'proxy fall-off' issue is addressed. See the Tamino graph here.
    And while marrying up the last century's temperature record at the correct equivilant reference temperature may not be an entirely trivial process, even if the temperature record was stuck on at an obviously low position, the resulting up-tick remains a feature of unprecedented suddenness.

  50. The History of Climate Science

    @ chriskoz - translation is underway!

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