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Comments 108551 to 108600:

  1. Blog review of scientific coherence
    A lot o peoples decision making, is emotional... Emotion dosnt necessarily have anything to do with logic, and its not restricted to one view point or another on a subject... it is a human condition. Passionate people cant be trusted to make rational decisions is what it comes down too. Their viewpoint will be the result of their upbringing. Not necessarily their IQ. But as i said, this is not restricted to one view point or the other in any subject! How can a scientist be religious? It happens, and it dosnt mean they are stupid. I have no time for emotional arguments, facts are what count. Wherever they happen to lead. For AGW, there is enough evidence to convince me we are effecting climate through co2 emissions. As to the extent, that is why im interested in the subject, id like to have an informed opinion... And from what i have read on the subject, this is still a bit o a grey area, as far as water vapor feedback go... so someone passionately preaching catastrophe falls into the same category to me, as those you call denialists... passionate people ;-)
  2. Billions of Blow Dryers: Some Missing Heat Returns to Haunt Us
    @TTTM: wishing it won't make it so. Some of heat *is* there, there's no reason to believe there isn't more in other abyssal depths and such. What we know is that we don't have an accurate picture of the entire oceans as far as temperature goes - yet contrarians and deniers have no problems affirming there's missing heat, which in their politically-motivated minds means AGW is no longer happening. As we've shown, the P&J paper remains unscathed by your criticism. Now would be a good time to admit you were wrong and move on.
  3. Blog review of scientific coherence
    This is some funny and insightful commentary on the psychology of global warming denial. That said, my reaction while reading it was something like this: "I know the 'skeptic community' puts forth all these contradictory arguments, but is it really true that any one individual will say that the earth isn't warming *and* that it is warming naturally?" I was relieved when I read that "an analysis of a single “skeptic” website reveals 239 such contradictions" - but where's the link? I can easily imagine that you analyzed such a site, but I can also imagine that it's a site comprising many individual viewpoints - 239 of them, even - but that none of them are themselves incoherent. If that's the case, that's fine, it still demonstrates that the denialist movement is incoherent, but it kind of undermines the "your resident skeptic" piece of the essay. Anyway, I'd be happier if I knew who or what you were talking about and could assess the claim for myself.
  4. Does Climate Change Really Matter?
    Muoncounter, no, absolutely there's no way to have too much water. Witness Stanislav Lem's character Ijon Tichy: ...Tichy has to escape from a planet whose government has legislated that all of its inhabitants shall henceforth breathe underwater. The citizens sing patriotic anthems about fish and humidity, and learn that in a future paradise all shall become "gwats" and "sunkers," idealized water-breathing forms. Debates rage over whether gurgling is allowed. Perhaps pro-fossil fuel lobbyists are bureaucrat emissaries from another planet, tricking libertarians here into joining their submarine totalitarian aquatopia?
  5. Tarcisio José D at 10:42 AM on 29 September 2010
    Blog review of scientific coherence
    "The beauty of this is that you don’t need data or peer-reviewed science to be sure: If an argument is incoherent or mutually contradictory, then you can be confident that it is wrong." I'm sure, widout of peer-reviewd science, bat "greenhouse effect,the bigger the better" because it's no water in the soil for to control the temperature of the enviroment. It's easy to see at www.scam.com.br/tjdavila/solo/pesquisa.html Very nice post Mr. Stephan
  6. Climate scientists respond to Monckton's misinformation
    It depends on the diagnosis, Ken. There'd probably be a second opinion from an expert, but if both experts concluded the same thing, and it was bad news, then the patient would probably . . . go looking for people who would tell him/her exactly what he/she wanted to hear. And if such a person was readily available--indeed, if many such people were being paid to be readily available--then it would be all too easy to jump on the bandwagon. At the funeral, many people would lament and blame everything on the liberal media. I appreciate the thorough debunking of Monckton, but it appears that the surface of the earth would have to be scoured of life before he admitted only to being wrong. As for the admission of deliberate disinformation, it'll never cross his lips, even if he were waterboarded. At most, confronted with the outcome of the disinformation campaign, he'd say he thought he was doing the right thing--the noble excuse of the ignorant wealthy.
  7. Blog review of scientific coherence
    Nicely put Stephen. Wait for the flood of angry denials from, well, denialists, that there is anything contradictory or incoherent in their objections. And I think, in most cases, genuine denials. These people it seems to me live for the moment. A scientist makes a finding on, say, Greenland ice cover, or coral bleaching, or storm frequency. It is a single finding but it is consistent with all the thousands of other findings on global warming in the last thirty years. A scientist reading it will say, "oh, that's interesting, that matches what we know from x", or, "I wonder why the minor inconsistency with y". A denialist reading it has quite a different reaction. For him, or occasionally her, this finding is another threat to a world view in which global warming is not happening, can't be happening, so it must be met with an instant rejection. Greenland was once green, for example, or coral has bleached before, or there were more storms in 1750. Doesn't matter, the important thing is to find a way of denying this single finding, of creating an illusion that a contrary view is not only possible but far more likely. In doing this the denialist has no memory of what he said the previous day or week or year. and little interest in other rejections of the finding. A denialist lives for the moment, sufficient unto the day is the current rejection. We, looking objectively from outside, and not having the amnesia so typical of deniers, sees that all these "answers" are contradictory, can't all be true, wonder why the deniers can't settle on, say, "yes, global warming is happening but it isn't anthropogenic" OR "global warming isn't happening, the models/instruments/proxies are faulty" OR "global warming is happening and has happened before, often (as the models/instruments/proxies tell us) ", rather than trotting out whichever of these suits the purpose on a given day. But if they were to do that they would be thinking in scientific terms (hypothesis/experiment/revised hypothesis) and that isn't what is going on here. The denialist sees himself as at war with the scientific establishment/Greens/UN/socialism and will say whatever it takes to keep winning that war, one battle at a time. And if in doing so they contradict themselves, well then, they contradict themselves.
  8. Does Climate Change Really Matter?
    #27: "no deleterious effect on human culture, regardless of the exact manner of distribution." Curiouser and curiouser. I thought there was ample precedent for problems caused by an excess of rain.
  9. Billions of Blow Dryers: Some Missing Heat Returns to Haunt Us
    Alternatively the heat simply isn't there and the theory is deficient and isn't taking into account negative feedback sufficiently.
  10. A detailed look at galactic cosmic rays
    #19: "they may contribute to explaining the fact that clouds are often charged on their top and bottom surfaces as GCR's may ionise existing droplets." Glenn, Interesting post. Looking at the abstract of the GRL article cited in the New Scientist post you mention, I don't see any specific mention of GCRs as opposed to solar cosmic rays: Cloud edge droplet charging is expected from vertical flow of cosmic ray generated atmospheric ions in the global electric circuit. Its long been known that solar cosmic rays (mostly muons - my personal favorite), are ionizing. The origin of cosmic ray research was an effort to explain why charged, shielded electroscopes spontaneously lost their charge. Solar cosmic rays are vastly more abundant than GCRs and thus would be more likely candidates for 'cloud edge droplet charging.'
  11. Does Climate Change Really Matter?
    Yes, muoncounter, more precipitation seems to be the inevitable outcome but the assumption is apparently that it will have no deleterious effect on human culture, regardless of the exact manner of distribution. Meanwhile, there will never be a shortage of arguments. We are nothing if not ceaselessly inventive.
  12. Billions of Blow Dryers: Some Missing Heat Returns to Haunt Us
    TTTM, I think you've been led into making incautious statements about P&J's paper by my remarks on attention being focused on missing OHC by flattening temperature increases over the past 5 years. In point of fact, the bit of OHC considered sufficiently solid to include in IPCC syntheses has been deficient for some time prior to 2005. See ARG WG1 5.2.2 Ocean Heat Content There's nothing in P&J's paper not included in the abstract for you to argue with. Read carefully, starting with the first sentence: We quantify abyssal global and deep Southern Ocean temperature trends between the 1990s and 2000s to assess the role of recent warming of these regions in global heat and sea level budgets.We compute warming rates with uncertainties along 28 full-depth, high-quality, hydrographic sections that have been occupied two or more times between 1980 and 2010. Nothing about 2005-2010, yes? Meanwhile, I think your attention was seized by my sentence: The main reason for lamentation of "Trenberth's Travesty" is the declining upward pace over the past 5 years of the portion of ocean heat content (OHC) we're readily able to measure. I could have said that better. I could have said, "The main reason for recent increased attention..." or words to that effect. Unfortunately I've thereby tempted you into making some rather incautious and wrong flings against P&J. Sorry about that, I'll try to do better next time. What P&J have done is to have formed this conclusion, which will stand until somebody (not you I suspect) shows otherwise: Excepting the Arctic Ocean and Nordic seas, the rate of abyssal (below 4000 m) global ocean heat content change in the 1990s and 2000s is equivalent to a heat flux of 0.027 (±0.009) W m–2 applied over the entire surface of the Earth. Deep (1000–4000 m) warming south of the Sub-Antarctic Front of the Antarctic Circumpolar Current adds 0.068 (±0.062) W m–2. The abyssal warming produces a 0.053 (±0.017) mm yr–1 increase in global average sea level and the deep warming south of the Sub-Antarctic Front adds another 0.093 (±0.081) mm yr–1. Thus warming in these regions, ventilated primarily by Antarctic Bottom Water, accounts for a statistically significant fraction of the present global energy and sea level budgets. They appear to have identified a substantial portion of "missing heat," which has been understood by most people for a long time to be missing not in the sense of absent from existence but missed from our ability to confidently measure. I've got maybe a touch of overenthusiasm for locating this heat. I suspect it'll mostly be found in dribs and drabs, in the manner of P&J, with ultimately some under or overshoot that's going to be increasingly difficult to resolve from sensitivity estimate errors, ultimate measurement limitations, etc. The capacity of the ocean is such that the remaining gap may be breathtaking in absolute terms but small in proportion to the total load we're taking on.
  13. Does Climate Change Really Matter?
    #25: "some skeptics are recently touting increased convection" Seriously? Are they running out of arguments? From MIT's Center for Global Change Science: But convection has two competing effects: increased convection forces increased subsidence in the environment of clouds, which is a strong drying effect; but increased convection also increases the rate at which water vapor from near the Earth's surface is transported to higher altitudes. However the bulk of this water vapor condenses as it rises and falls out as precipitation leaving open how much is actually available to moisturize the atmosphere. Doesn't that suggest that increased convection -> more precipitation, just like the events you describe?
  14. Billions of Blow Dryers: Some Missing Heat Returns to Haunt Us
    @TTTM: What is your obsession with the 2005-2010 period, anyway? From the paper's abstract: "We compute warming rates with uncertainties along 28 full-depth, high-quality, hydrographic sections that have been occupied two or more times between 1980 and 2010." Who said that readings had to be limited to 2005-2010 to be useful. Oh, right: you. You seem to believe that readings have to be in that period in order to be significant, but that misses the whole point. This paper is not specifically about that period, but rather seeks to show how heat fluxes through the abyssal oceans. I'm sorry, but you simply have failed to challenge the science contained in the P&J paper. They have enough data to show a significant heat movement below 4,000m, thus giving a clue as to the true nature of the apparent hole in the global heat bugdet.
  15. A detailed look at galactic cosmic rays
    Interesting article in this weeks New Scientist about possible links between the Solar Cycle and climate. The mention Svensmarks theory and that it has issues, but also mention another mechanism where GCR's may have more impact. Rather than creating CCN's to seed cloud formation, they may contribute to explaining the fact that clouds are often charged on their top and bottom surfaces as GCR's may ionise existing droplets. Speculation is that this could impact on the lifetime of a cloud, precipitation rates from a cloud etc. Certainly a more plausible then Svensmarks more convoluted mechanism. But these may not be the only impacts of Solar variability. Possibly variations in solar wind and magnetic field strengths could impact on the rate of deposition of cometary and meteoritic dust from space, another source of CCN's. Preliminary evidence suggests that although TSI only varies by about +/- 0.1% over a solar cycle, the Ultraviolet component of this may vary by as much as 1-2%. Ultraviolet is preferentially absorded in the stratosphere by ozone, but in addition UV is also part of the cycle vy which Ozone is actually created and destroyed, as well as the processes by which CFC's are destroyed, all of which can impact on climate. Also the stratosphere is where methane is converted to CO2 & Water so changes in the chemistry up there due to Solar cycle influences could impact on levels of Methane. Interestingly, Methane levels in the atmosphere plateaued for much of the 2000's, only to resume rising towards the end of the decade, roughly in line with the 'It hasn't warmed since 1998' period. Coincidence? And there may well be other mechanisms yet to be found by which different components of the solar system that vary with the solar cycle may have climate impacts - UV, Solar wind, Magnetic Field strengths, Simply correlating just GCR's to Atmospheric Temperature variability alone and implying a single major forcing here is stretching too long a bow. I suspect we will find a range of different mechanisms, caused by different phenomena associated with the solar cycle that each make modest contributions to climate variability. This doesn't in any way detract from the central theories about AGW that are based on solid radiative physics. Rather these would be simply additional secondary mechanisms that contribute to climate variability. Put simply, AGW currently describes the physics driving underlying trends. A range of other factors, including but not limited too solar cycle factors probably explain shorter term climate variability that is overlaid on top of the underlying trend. And periods such as a decade of lesser warming is still just short term variability.. Never forget, to produce his graph correlating GCR's with temperature Svensmark not only removed the impacts of ENSO, Volcanoes etc to reveal the residual impact, but also he had to remove a .14 DeC PER DECADE TREND as well. AGW due to GH Gases AS WELL as Solar Cycles influences. Not INSTEAD OF.
  16. Blog review of scientific coherence
    To interject a bit of humor you might add that only in quantum mechanics can the apple both not exist and be natural. ;-)
  17. New temperature reconstruction vindicates ...
    It's interesting how Loehle (corrected paper) does the "reconstruction." It's just a simple average across years of all the (smoothed & anomalied) proxy series instead of any regression-based method (maybe I'm reading it incorrectly, but it seems like a very weak and inconsistent way of reconstructing temperatures even if the proxies are chosen carefully). Anyways, another way to compare to the instrumental data is to actually do a regression-based proxy reconstruction. So I calibrated the mean data vs. the CRUTEMP3v data using simple linear regression, and used those parameter estimates to project them back.
  18. Billions of Blow Dryers: Some Missing Heat Returns to Haunt Us
    I've read it Doug. I've made my point, its just that you either dont understand it or dont want to accept it. They simply dont have any data for most of their "stations" in the period of interest. They can say nothing about what the OHC is actually doing during that time as a result. Its not interpolation Doug. There is simply NO DATA to have interpolated with. Its an extrapolation from the last data point some time before 2005 through to the end of 2010.
  19. Billions of Blow Dryers: Some Missing Heat Returns to Haunt Us
    Make your point, TTTM, I don't want to engage with you in Socratic debate and anyway your argument is not with me. You've got a lot of details to wade through starting in section 2 before you're going to make a dent in P&J beyond pointing at a single figure and hoping we'll think there's some problem with the analysis; I'm sure figure 2 is very alluring but then it's a picture, after all, doesn't pretend to describe the experiment. These "debates" are so rarely a fair fight. You're not arguing with me; I'm simply reporting findings of a team with decades of specialized training, total dedication and commitment to their subject, armed with relatively ample resources, who in turn lean on the expertise of other people with centuries of similar experience between them. You're one guy with Google who apparently can't distinguish between extrapolation and interpolation, but maybe that's deceptive and you'll make a real case against the authors. Meanwhile my only possibly useful role here in this comments thread is to point out when you're just saying "I doubt it."
  20. Billions of Blow Dryers: Some Missing Heat Returns to Haunt Us
    With regards to my previous post (#55), I'd like to specify I know 5 years is way too short to establish a trend. However, since it seems good enough for NETDR, then the least I could do was show him that trends are in fact positive (even if by a very small amount).
  21. Billions of Blow Dryers: Some Missing Heat Returns to Haunt Us
    Doug I'll ask you a simple question to prove my point. What does the data (see figure 2) for the following stations show for the period 2005 through 2010? A01, A02, A10, A12, A20, A22, I03, I04, I09S, P02, P10, P17, SR03 and SR4
  22. Billions of Blow Dryers: Some Missing Heat Returns to Haunt Us
    @TTTM: as I stated before, absence of evidence isn't evidence of absence.
  23. Billions of Blow Dryers: Some Missing Heat Returns to Haunt Us
    @doug_bostrom: damn, I just noticed that bit at the end myself. If I'd read it first, I wouldn't have taken the time to respond to him. Hey, NETDR, this isn't a political discussion site. Cut that crap.
  24. Billions of Blow Dryers: Some Missing Heat Returns to Haunt Us
    @NETDR: wow, so many erroneous statements in just a few sentences, I'm impressed! "So far the warming has been far below the 6 ° C rate the scientists want to use for a doubling of CO2." Climate sensitivity is estimated to be around 3C, not 6C. "Since we have had 1/3 of a doubling of CO2 we should have had more than 2 ° C warming we haven’t had this." As BP noted, it's much closer to 1/2 than 1/3. "0.7 ° C is the accepted value and less than ½ of that is from CO2 in the best case." Actually, it's closer to 0.9, and there's not indication that less than 50% of that is due to CO2. In fact, other factors (PDO, TSI, etc.) indicate we should be cooling, and yet temps have kept increasing. In any case, there is a lag before the full effect of CO2 warming is felt, so there's no reason the current warming is lower than what scientists estimate. "To get around this scientists have speculated that the ”missing heat” is stored in the oceans !" It probably is. "The problem is that since 2005 both atmosphere and the ocean have been cooling." Actually that is incorrect. Temperature trends since 2005 are positive. Furthermore, the point of this article is precisely that we're finding areas where some heat has gone that weren't being measured, and thus it's likely there are more of these. You should learn a bit more on the subject before posting such comments.
  25. Billions of Blow Dryers: Some Missing Heat Returns to Haunt Us
    Despite all of this “the debate is over” and we should throw ten’s of trillions of dollars at the nearest politician to make it go away. Oh, brother, didn't notice that until just now. So we're not talking science, we're talking politics? Searching for "politics" the only semi-appropriate thread I find here is Why I care about climate change. If you're here because you care about politics and climate change, try that.
  26. The Phony War: Lies, Damn Lies and the IPCC
    For shits and giggles, here's what NOAA (who uses the same graph from Kerwin 1999) has to say: "In summary, the mid-Holocene, roughly 6,000 years ago, was generally warmer than today, but only in summer and only in the northern hemisphere. More over, we clearly know the cause of this natural warming, and know without doubt that this proven "astronomical" climate forcing mechanism cannot be responsible for the warming over the last 100 years."
  27. The Phony War: Lies, Damn Lies and the IPCC
    @CW: I didn't ask for references that summers were hotter and winters colder, but that the climate was more "extreme". You haven't provided this. You also seem to think the warming was global, but the reality is that the tropics and the southern hemisphere actually cooled. At around 30 degrees North, the effect wouldn't have merely been "smaller," it would have been negligible. As far as overall temperatures goes, these were lower, not higher. Not that this really matters, anyway; we have a pretty good idea what caused the HCO, and we know that's not what's happening today. Even if the HCO had been warmer (and it wasn't, as far as we can tell), it still wouldn't change the fact the current warming is very likely caused by a rise in atmospheric CO2. "But imagine winters were a million degrees colder" Absolute zero is −273.15°C. You can't get any colder than that (actually, you can't even get there).
  28. Billions of Blow Dryers: Some Missing Heat Returns to Haunt Us
    Care to retract your remarks about "extrapolations," TTTM? If you can't tell the difference between "extrapolation" and what P&J did in their paper, it's not only more obviously pointless arguing with you, you also rob yourself of credibility. Meanwhile, you've also created for yourself the problem of your assertion, "The research doesn't ACTUALLY show warming at all. It assumes it." You've not shown that. Typing the words is a miniscule fraction of the effort you need to invest in lending those words worth. NETDR, interesting points, but you're slipping behind. If you can show how P&J are incorrect, you may then assert that they've not located where approximately 20% of the famous "missing heat" may reside. The point of the article is that progress appears to have been made in solving this mystery. Repeating old information does not address new results. Really, people need to roll up their sleeves and do some work here, talk less.
  29. Is Greenland losing ice? (psst, the answer is yes, at an accelerating rate)
    Okay, if we're going to talk about sea level rise and all this stuff, Check out Bamber and Riva (2010) http://www.the-cryosphere-discuss.net/4/1593/2010/tcd-4-1593-2010.pdf
  30. Billions of Blow Dryers: Some Missing Heat Returns to Haunt Us
    Look at the data Doug. Suggestions of OHC increasing from 2005 through 2010 is largely manufactured because supporting data simply doesn't exist.
  31. Climate scientists respond to Monckton's misinformation
    I have this analogy that I would like some help with. If a patient with a heart condition sought an opinion from a heart doctor, this would be considered normal. If this patient sought an opinion from a foot doctor, about his heart condition, the patient would seem to be, at the very least, silly if not downright stupid. But what if that foot doctor actually gave an opinion about the patient's heart condition, what is that called? Unethical? Immoral? Perhaps even illegal? Would not that foot doctor receive some kind of condemnation from the medical community? So why then, are non-experts in climate science allowed to continue to stand beside true experts as equals?
  32. Does Climate Change Really Matter?
    Further to muoncounter's remarks, it's odd that some skeptics are recently touting increased convection as an easy and hopefully transparent means of somehow avoiding energy gain on the planet. Strange events such as the 9.6" of rain in 36 hours (normally 4.5" for the month) causing a historically novel flood in Bella Coola, BC last weekend may offer hints that we should not expect intensified convection to be benign, let alone a magic pathway to the stars for energy. On a grander scale than charming but tiny Bella Coola, try HowBigReally to see Pakistan's flooding this year, compared to California, USA. Tip of the hat to Skeptical Science's host country, here's Australia compared to Pakistan's rising damp.
  33. The Phony War: Lies, Damn Lies and the IPCC
    CW - I agree that HCO was probably warmer - that is what the IPCC report says too. However, you claimed it was more "extreme" which implies ... what? I would say the evidence was warm and more important, settled.
  34. Hockey stick is broken
    GC - I asked for specific instance of Tamino criticism for a very good reason - I wanted evidence that Tamino was defending the indefensible as your accusation implied. Which paper do you think is the definitive account of the historical record that you think so reliable? (and the answer had better not be Lamb). I'll stand by my statement that individual proxies reflect local historical record while acknowledging that combining them into a multiproxy record is difficult. Loehle is hardly criticised for excluding tree proxies - other papers have done the same - but for numerous other errors. If he had published in something other than E&E then he might got some quality feedback for improvement instead of having to publish corrections later. The problem with leaving tree proxies out is that is all you have for too periods of too many regions. Undoubted more data will help improve this situation. I would also note very small difference between Mann 2009 and latest from Ljungqvist. Is Mann still "denying" history, but Ljungqvist isnt? McIntyre would have some credibility if he actually published instead of just misleading statements and innuendo from the sidelines.
  35. Hockey stick is broken
    GC, it sounds as though you're in tacit agreement that recent observations of Arctic ice extent, loss of terrestrial ice mass in both hemispheres, globally shrinking diurnal temperature variations, lopsided extreme heat statistics, an upward trend in ocean heat content, increasing signs of intensified convection plus a lengthy list of other consistent indicators with which you are probably painfully familiar all point to a modern change in climate? These are after all recorded in superior cultural records to the instrumentally void and comparatively sparse narratives you consider to obviate proxy temperature data. Looking at your opinion from a different perspective, I'd say your endorsement of historical records bolsters the case for new and startling history being made today. Meanwhile, a differently advanced cultural heritage provides us with a plausible explanation for our present observations. The past is not necessarily prologue; we'll need to look farther back in time to seek an offset of sufficient span and power to be capable of nullifying the secular trend we appear to have started. Once we dip farther back in chronology than historical time, your faith will have to be fully invested in proxies, if you're to seek solace in anachronism.
  36. New temperature reconstruction vindicates ...
    Alden... Your graphs are way better than mine. :-)
  37. New temperature reconstruction vindicates ...
    Wow, Alden....I'm impressed. Thanks for doing all this! Very interesting (and telling).
  38. Does Climate Change Really Matter?
    #15:"lack of data to support the premise that warming will drive more extreme weather events." For context, here is an interesting summary of the changing pattern of observed climate extremes during the 2nd half of the 20th century (from 2002): Observed coherent changes in climatic extremes during the second half of the twentieth century Frich et al. 2002 Coherent spatial patterns of statistically significant changes emerge, particularly an increase in warm summer nights, a decrease in the number of frost days and a decrease in intra-annual extreme temperature range. All but one of the temperature based indicators show a significant change. Indicators based on daily precipitation data show more mixed patterns of change but significant increases have been seen in the extreme amount derived from wet spells and number of heavy rainfall events. We can conclude that a significant proportion of the global land area was increasingly affected by a significant change in climatic extremes during the second half of the 20th century. ... ... for the global land areas examined, on average during the second half of the 20th century, the world has become both warmer and wetter. ... These observed changes in climatic extremes are in keeping with expected changes under enhanced greenhouse conditions.
  39. New temperature reconstruction vindicates ...
    Albatross... Thanks. Just a little reprisal from months ago when I wrote Kung-fu Climate... Even using numbers that Loehle provided for me, with his own acknowledgement that they were an apple-to-apple comparison, we see that current warming IS unprecedented. And this doesn't even account for the fact that: 1) Loehle's figures are mostly NH 2) The Hadley figures still stop over a decade ago 3) Loehle's figures are the most exaggerated of any of the reconstructions So, even with all those handicaps current warming is still more rapid and higher than any time in the past 2000 years. And, as you say Albatross, if Loehle is anything close to right that suggests a climate sensitivity that... well, we don't wanna go there, that's for sure.
  40. New temperature reconstruction vindicates ...
    As I mentioned in my earlier comment, Loehle doesn’t provide a standardized base period for his temperature series - “All data were then converted to anomalies by subtracting the mean of each series from that series.” And at the end of the paper he comments, “While instrumental data are not strictly comparable, the rise in 29 year-smoothed global data from NASA GISS from 1935 to 1992 (with data from 1978 to 2006) is 0.34 Deg C. Even adding this rise to the 1935 reconstructed value, the MWP peak remains 0.07 Deg C above the end of the 20th Century values, though the difference is not significant.” Another way to compare the two is to essentially recalibrate the reconstructed temperatures against the instrumental values. I adjusted Loehle, Ljungqvist, and HadCRU instrumental values to the base period 1850-1899. I then plotted the reconstructions with the land / land&sea instrumental values (using the same level of smoothing as the reconstructions), using global or hemispheric datasets where appropriate. Again, I’m not sure how Loehle feels vindicated:
    Moreover I wish the folks at WUWT would stop confusing the conclusion that there was a Medieval Warm Period (which there very likely was) with the separate conclusion that the recent temperature trend is rather unusual. That comes out in Loehle’s reconstruction as well. And more importantly, these graphs say nothing about whether it’s all a “natural cycle”. We have a pretty good understanding of why temperatures were warmer in the Middle Ages and why they were cooler in the Little Ice Age. We also have a really good understanding of why recent temperatures are increasing and that they will continue to do so. Let’s see what Loehle has to say in another 20 years... -Alden
  41. New temperature reconstruction vindicates ...
    Rob @20, "Am I missing something?" As far as I can tell, they (Loehle et al.) want to try and show that the current warming is not unprecedented. Their argument goes something like this "it has been as warm before and it is mostly natural cycles driving changes in global SATs". So, it seems, that they wish to try and detract people from the big elephant in the room, the blade. Their argument also ignores the fact that the blade is only going to get longer as the radiative forcing from increasing GHG concentrations increases. Also, the MWP and LIA are both indications that climate sensitivity is not as low as the "skeptics" would like think, b/c fairly large temperature departures in the past were invoked with very little forcing. Never mind that the inconvenient fact that temperatures are already much warmer than (reliable reconstructions indicate) for the MWP.
  42. New temperature reconstruction vindicates ...
    GC, [edit] Moreover, as can be seem for all to see here, Figure 2 above shows the Mann08 reconstruction, which has a very distinct MWP and LIA. Yet you insist on harping on about a 12-year old paper. Why? In case you have not noticed it is 2010 GC, the science has advanced and moved on, might I suggest that you do too...
    Moderator Response: Response to edited content was cut
  43. New temperature reconstruction vindicates ...
    People will have to pardon me if this is a silly question. Is there supposed to be something inherently profound about exactly what shape the hockey stick is? I keep getting this sense that Loehle is just pissed that Mann's original hockey stick graph was straight and he thinks it should have bends in it. He seems to go out of his way to try to make his own hockey stick (with hidden blade) as exaggeratedly bent as possible. But still, I keep coming back to the fact that what makes the hockey stick a hockey stick is the blade. Current warming. (We sure ain't playing Lacrosse here.) Loehle can tie the handle up in knots for all I care, it just seems to me that what is important is that current warming is unprecedented no matter how many crooks the handle has. Am I missing something?
  44. Is Greenland losing ice? (psst, the answer is yes, at an accelerating rate)
    fydijkstra @22, You are making deductions using data over too short a period of time to be of statistical significance, and have not supported why you chose 2005. I could take those SL data (you should actually be using the data with both the inverse barometer correction, and with seasonal signal removed), and could argue that the rate of increase from 2007 until present is 3.3 mm/yr, which is above the long-term trend of +3.2 mm/yr. See the CSIRO site . So focusing on short-term trends does not make sense-- b/c the data are so noisy one can select short windows of time to support whatever point of view you wish to make. The CSIRO also state that: "This data has shown a more-or-less steady increase in Global Mean Sea Level (GMSL) of around 3.2 ± 0.4 mm/year over that period. This is more than 50% larger than the average value over the 20th century."
  45. The Phony War: Lies, Damn Lies and the IPCC
    archiesteel, the orbital forcing of the HCO ( fairly well understood and calculable ) gave some 50 W/m^2 more sunshine at the TOA for the Arctic during summer, and some 15 W/m^2 less sunshine TOA for the Arctic winter. Similar, though smaller changes also occurred at lower latitudes, including around 30 degrees North where the Mesopotamian settlements were founded. Knowledge of temperatures is all from proxy, and less certain than the solar orbital forcing which is pretty solid. Still, the Arctic is analyzed to have been significantly warmer during the HCO than it is today: Now, this pertains only to the Northern Hemisphere. But that's where the Mesopotamian civilization was. Interestingly, there was quite a bit of Arctic ice melt with this period, but not Greenland. (not the high interior anyway). Also, it is interesting that winters were colder and summers were hotter. Overall temperatures were somewhat higher (summers were disproportionately hotter). But imagine winters were a million degrees colder, and also summers were a million degrees hotter. The average annual anomaly would be zero. But it would be a deadly zero. Sometimes, the average doesn't much.
  46. New temperature reconstruction vindicates ...
    Ned, Good post! Way better than my comment on "Is the Hockey Stick Broken" but I do have some quibbles. You say: "It's worth noting that all the reconstructions show the Medieval Warm Period, the Little Ice Age, and 20th-century warming (though Loehle 2008 only runs through 1935)." This is clearly not the case as Mann's original Hockey Stick denied both the MWP and the LIA. [edit]
    Moderator Response: Insinuations of ill intentions are not welcome. Next time the entire post will be deleted.
  47. Is Greenland losing ice? (psst, the answer is yes, at an accelerating rate)
    CBDunkerson: "One issue with the Wu analysis is that if significantly less ice has melted than previously thought then we have a bigger problem explaining the observed sea level rise. Any decrease in ice loss must be made up by increased expansion due to heating." The sea level rise can be explained very well from the gradual rise in temperature and the moderate ice loss from Greenland. Wu's suggestion that the Greenland ice loss is far less than was assumed so far is in perfect agreement with the fact, that there is no significant change in sea level rise. Contrary to popular claims the sea level rise is not accelerating. From 1993 to 2010 the sea level rose 2.7 mm/year. From 2005 to 2010 it was only 2 mm/year. These data can be checked here.
  48. Hockey stick is broken
    scaddenp & Co., With regard to Tamino, I have nothing to contribute to the discussion other than to say that I find "Climate Audit" more plausible than "Open Mind". The Tamino/McIntyre spat has turned into a cottage industry and good luck to both of them. Statisticians are like economists; if you put them all "End-to-End" they still won't reach agreement. The point I am trying to make is that if studies defy the historical record it is the studies that must be thrown out. Mann and his myriad supporters still insist that history be ignored but it is a battle they must ultimately lose. They should be ashamed for defending the indefensible. The post above and recent events support me. Take a look at Figure 1 that started it all. About 850 years with tiny variations and a very gentle decline followed by a rapid temperature rise. No sign of the MWP or LIA. Move on to Figure 2 that is almost identical to Figure 1. Shame on Wahl-Ammann! Still no sign of the MWP or LIA. The tiny variations are totally implausible when you consider the extreme weather events that occurred during the last 1,000 years such as the hot, dry summers around 1540 that caused major rivers in Europe to dry up. On the other extreme, the river Thames in London froze over on 24 occasions from 1408 to 1814. If you have not seen the following link before, enjoy! http://booty.org.uk/booty.weather/climate/1000_1099.htm Recently, the "Climate Science" community has begun to realize that their credibility has been ruined by historians so growing number of paleo-climate reconstructions show historical events as in Figure 6 (Mann 2008). Here, the MWP and LIA can be seen as minor excursions. What would happen if one left out the tree ring data? Here is a paper by Loehle with the answer: http://www.ncasi.org/publications/Detail.aspx?id=3025 This 2000 year reconstruction shows temperature excursions greater than 1 degree Kelvin and Medieval temperatures higher than 2010. Loehle has been demonized by establishment scientists such as Schmidt and Mann; nevertheless there are still folks like Ljungqvist who can produce similar results even with tree ring proxies included: ftp://ftp.ncdc.noaa.gov/pub/data/paleo/contributions_by_author/ljungqvist2010/ljungqvist2010.txt Climate science needs to stop muddying the waters by creating multi-proxy analyses that include even one proxy that fails the acid test of being consistent with history/archeology. Few if any tree ring proxies would survive and some other proxies might fail the cut too. The Ljungqvist paper covers 2000 years with decadal resolution using proxies located from 30N to 81N. It therefore covers the non-tropical northern hemisphere over recent historical times. The amplitude of temperature variations is 0.9 degrees compared to 3.3 degrees in Richard Alley's ice cores. However, global warming (or global cooling) should be much more pronounced at high latitudes (the central Greenland site was at 73N). When one overlays the temperature variations in Loehle 2007, Ljungqvist 2010 and Alley 2000 the historical features such as "Dark ages", MWP and LIA all show up in the right places so these analyses have some credibility, unlike MBH 98 et seq. apeescape, I read all those links (@43). Methinks they protest too much. Gavin in particular is beginning to sound a little desperate. He is paid to do what he does but he is not winning hearts or minds.
  49. New temperature reconstruction vindicates ...
    Robert Way writes: Isn't Moberg 2005 only NH? Argh, you're right of course. And while I could edit the text of the post, the "global" label is burned into the graphic of Figure 2. Well, I'll have to fix that... Anyway, thanks for pointing it out.
  50. New temperature reconstruction vindicates ...
    Zeke, looks like we had basically the same idea at the same time, right down to showing both land-only and land/ocean instrumental temperatures ... Although it looks like we used different approaches for centering the series. Zeke's lineup is more similar to Tamino's. This doesn't affect the amplitude of the reconstructions (e.g., the difference between the MPW peak and LIA trough) but it does make a difference in terms of comparison to current (instrumental) temperatures.

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