In China, there are no hockey sticks

Climate research, Tibet, Tree rings, Lui et al 2011Reposted from Jo Nova’s site

Chinese 2485 year tree ring study shows shows sun or ocean controls climate, temps will cool til 2068

A blockbuster Chinese study of Tibetan Tree rings by Lui et al 2011 shows, with detail, that the modern era is a dog-standard normal climate when compared to the last 2500 years. The temperature, the rate of change: it’s all been seen before. Nothing about the current period is “abnormal”, indeed the current warming period in Tibet can be produced through calculation of cycles. Lui et al do a fourier analysis on the underlying cycles and do a brave predictions as well.

In Tibet, it was about the same temperature on at least 4 occasions — back in late Roman times — blame the chariots, then again in the dark ages — blame the collapse of industry; then in the middle ages — blame the vikings; in modern times — blame the rise of industry. Clearly, these climate cycles have nothing to with human civilization. Their team finds natural cycles of many different lengths are at work: 2-3 years, 100 years, 199 years, 800 years, and 1324 year. The cold periods are associated with sunspot cycles. What we are not used to seeing are brave scientists willing to publish exact predictions of future temperatures for 100 years that include rises and falls. Apparently, it will cool til 2068, then warm again, though not to the same warmth as 2006 levels.

On “tree-rings”

Now some will argue that skeptics scoff at tree rings, and we do — sometimes — especially ones based on the wrong kind of tree (like the bristlecone) or ones based on small samples (like Yamal), ones with abberant statistical tricks that produce the same curve regardless of the data, and especially ones that truncate data because it doesn’t agree with thermometers placed near airconditioner outlets and in carparks. Only time will tell if this analysis has nailed it, but, yes, it is worthy of our attention.

Some will also, rightly, point out this is just Tibet, not a global average. True. But the results agree reasonably well with hundreds of other studies from all around the world (from Midieval times, Roman times, the Greenland cores). Why can’t we do good tree-ring analysis like this from many locations?

Jo


 Amplitudes, rates, periodicities and causes of temperature variations in the past 2485 years and future trends over the central-eastern Tibetan Plateau [Chinese Sci Bull,]

Climate research, predictions, Lui et al 2011Figure 5 Prediction of temperature trends on the central-eastern Tibetan Plateau for the next 120 years. Blue line, initial series; orange line, calibration series, 464 BC–834 AD; purple line, verification series, 835–1980 AD; red line, forecasting series, 1980–2134 AD. (Click to enlarge)

There are beautiful graphs. Have a look at the power spectrum analysis and the cycles below…

 

ABSTRACT:

Amplitudes, rates, periodicities and causes of temperature variations in the past 2485 years and future trends over the central-eastern Tibetan Plateau

Amplitudes, rates, periodicities, causes and future trends of temperature variations based on tree rings for the past 2485 years on the central-eastern Tibetan Plateau were analyzed. The results showed that extreme climatic events on the Plateau, such as the Medieval Warm Period  Little Ice Age and 20th Century Warming appeared synchronously with those in other places worldwide. The largest amplitude and rate of temperature change occurred during the Eastern Jin Event (343–425 AD), and not in the late 20th century. There were significant cycles of 1324 a, 800 a, 199 a, 110 a and 2–3 a in the 2485-year temperature series. The 1324 a, 800 a, 199 a and 110 a cycles are associated with solar activity, which greatly affects the Earth surface temperature. The long-term trends (>1000 a) of temperature were controlled by the millennium-scale cycle, and amplitudes were dominated by multi-century cycles. Moreover, cold intervals corresponded to sunspot minimums. The prediction indicated that the temperature will decrease in the future until to 2068 AD and then increase again.

Climate research, Tibet, Tree rings, Lui et al 2011Figure 1 Tree-ring-based temperature reconstruction for the central-eastern Tibetan Plateau during the past 2485 years (gray line), the 40-year moving average (thick black line) and the 40-year running standard deviation (thin black line); the horizontal line is the mean temperature for the 2485 years. (Click to enlarge)

Lui-2011-power-spectrumFigure 2 Power spectrum analysis of the 2485-year temperature series. (Click to enlarge)

Lui-2011-cycles of warming and cooling 2485 yearsFigure 3 Millennium-scale cycle in the temperature variation during the last 2485 years. (Click to enlarge)

Climate research, Tibet, Tree rings, Lui et al 2011Figure 4 Decomposition of the main cycles of the 2485-year temperature series on the Tibetan Plateau and periodic function simulation. Top: Gray line,original series; red line, 1324 a cycle; green line, 199 a cycle; blue line, 110 a cycle. Bottom: Three sine functions for different timescales. 1324 a, red dashed line (y = 0.848 sin(0.005 t + 0.23)); 199 a, green line (y = 1.40 sin(0.032 t – 0.369)); 110 a, blue line (y = 1.875 sin(0.057 t + 2.846)); time t is the year from 484 BC to 2000 AD. (Click to enlarge)

 Conclusions

Climate events worldwide, such as the MWP and LIA, were seen in a 2485-year temperature series. The largest Figure 6 Temperature comparison between the forecast and observation data taken from seven stations on the central-eastern Tibetan Plateau (seven stations: Delingha, Dulan, Golmud, Lhasa, Nagqu, Dachaidan and Bange). amplitude and rate of temperature both occurred during the EJE, but not in the late 20th century. The millennium-scale cycle of solar activity determined the long-term temperature variation trends, while century-scale cycles controlled the amplitudes of temperature. Sunspot minimum events were associated with cold periods. The prediction results obtained using caterpillar-SSA showed that the temperature would increase until 2006 AD on the central-eastern Plateau, and then decrease until 2068 AD, and then increase again. The regularity of 600-year temperature increases and 600-year decreases (Figure 3) suggest that the temperature will continue to increase for another 200 years, since it has only been about 400 years since the LIA. However, a decrease in temperature for a short period controlled by century- scale cycles cannot be excluded. Obviously, solar activity has greatly affected temperature on the central-eastern Plateau. However, there are still uncertainties in our understanding of climate change, and the  concentration of CO2 affects the climate. Further investigations are thus needed. -

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REFERENCES

Liu Y, Cai Q F, Song H M, et al. Amplitudes, rates, periodicities and causes of temperature variations in the past 2485 years and future trends over the central-eastern Tibetan Plateau. Chinese Sci Bull, 2011, 56: 29862994, doi: 10.1007/s11434-011-4713-7 [ Climate Change over the Past Millennium in China.] … Hat Tip: Geoffrey Gold.

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264 thoughts on “In China, there are no hockey sticks

  1. Tree rings also show growth can be affected by drought or lack of rain, sunshine, etc.

    True but there are ways of mitigating that. For example, select trees that live in areas that generally get very little / no rain at all during their growing season or trees that generally get way more than enough rain. Edge of treeline trees at high altitude work well because they don’t get a lot of rain anyway, most of their water is from snow melt, the trees are not close together and don’t shade each other, and temperature appears to be the primary growth limiting factor. Though they do stupid things like core strip bark bristlecones sometimes.

    I don’t favor trees as temperature proxies because at best they only proxy for 2 (sometimes 3) out of the 12 months of the year.

  2. Crosspatch I agree. But as most people live in the Northern Hemisphere, it will be there that most of the impact of cold weather will be felt mainly affecting the growing seasons.We must act now because we could have a several years of poor agricultural economy and that will cause problems. A hungry lion is more dangerous than a fat content one.

  3. Please keep in mind that tree rings will only show trends in summer temperatures and then it will only show early summer — June and July. The main factors in tree rings are the onset of summer growth and June/July temperatures. The onset of growth is generally constrained by when the snow melts. So a late slow melt can delay initiation of growth for the year and reduce the overall size of the annual ring for that year.

    http://academic.engr.arizona.edu/HWR/Brooks/GC572-2004/readings/vaganov-nature-siberia-tree-snow.pdf

    But generally, summer temperatures will trend with general climate, though not always. Since 1998 in the continental US, for example, summer temperatures are flat while winter temperatures have been plummeting. Overall annual temperatures are in decline but summer temperatures are flat. Tree rings in North America probably do not show the decline that the instrument record does in annual average temperature observations show (NCDC’s website).

  4. Fourier analysis on time series may be a lot of fun but until physical background of identified cycles is demonstrated it’s not more than just playing with numbers with zero predictive potential.

  5. Hmm, this validates a hunch I had for a 700+ year cycle in the data that was presented last week in a comment thread where we were looking at spectrum analysis of the CET temperatures. A very similar waveform showed up but the analysis was only for periods <100 years.

  6. sombody should tell our so called australian prime minister about no hockey sticks. the goose has her head in the sand

  7. Ahh, here it is:

    http://www.vukcevic.talktalk.net/CET-NVa.htm

    Basically reaches the same conclusion with a different data set (CET). Only this one shows temperatures declining to 2040-ish before rising again, but not to the current level before again dropping off. I would say this adds more weight to the notion that we are likely to see a fairly significant multidecadal drop in temperatures.

  8. Oh and the manufacture Solar and wind turbines. They haven’t come out to say there will be no warming or cooling, just in case. They picked a high altitude country too. Nevertheless, they have agreed on one point, it ain’t unusual….IF temps fall suddenly in the Northern Hemisphere that will be telling. Look as a kid in UK, both north and south, it was always cold and raining. We didn’t always have snow at Christmas time, but certainly Jan and Feb, even as late as Easter.
    And for the next chapter, see what the other think of it.

  9. I just heard a loud popping noise. I suspect Michael Mann’s head has exploded. Is there a direction from which he isn’t catching fire?

  10. This is absolutely beautiful. The data is spectacular in it’s beauty. The presentation is simple, concise and credible. It sets-out to destroy the hockey stick, re-instate the LIA and MWP as world-wide occurrences, and completely buries the CAGW hypothesis in cherry blossoms. Sweetly devastating.

    Brilliant!

  11. Fourier analysis on time series may be a lot of fun but until physical background of identified cycles is demonstrated it’s not more than just playing with numbers with zero predictive potential.

    Well, I sort of agree with that to some extent in that yes, it would be nice to know what enables each of these periodic cycles but if it proves out to be correct, we don’t need to know what enables them to accept that they are there. We learned there were 11 year (and other longer) sunspot cycles before we had any indication of what caused them and in some cases still don’t know why some of them are there. We still don’t know what causes Markowitz wobble (though several ideas have been put forward) but we know it’s there and accept it.

  12. “The regularity of 600-year temperature increases and 600-year decreases (Figure 3) suggest that the temperature will continue to increase for another 200 years, since it has only been about 400 years since the LIA.”

    Is this part: “about 400 years since the Little Ice Age” a typo?

  13. Does Bull stand for bulletin or bullshit? – I mean, where’s the magic word? Is it peer reviewed, is this a respected publication outside China? You were furious about Muller, obviously, because you didn’t like the conclusion. And now? Obviously, this time you like the conclusion – but what about peer review?

  14. M.A.Vukcevic says:
    December 7, 2011 at 11:33 pm

    I noticed when you posted on this last week that your analysis only looked for components with a period of 100 years or less. I remember noticing at the time that there seemed to be a component somewhat longer than 700 years and this analysis out of China finds an 800 year component. I asked in that thread if the 100 years was a limitation of your analysis software but maybe you answered me after I stopped following the thread or thought it was a nonsensical question given the length of the CET series.

  15. We must act now

    Yes, we must act now. Tell you what. If you can convince the government to give me a grant of only five million dollars, I will maintain a temperature series that I shall keep adjusting so that I make the cold go away.

    In all seriousness, you can adapt to a 1 degree temperature rise quite easily. You can’t adapt to a 1 degree global average decline unless frequent fasting is major part of your adaptation strategy.

  16. Kasuha: “Fourier analysis on time series may be a lot of fun but until physical background of identified cycles is demonstrated it’s not more than just playing with numbers with zero predictive potential.”
    It is more than just fun, Kasuha. The fourier analysis is done to show the dominant frequencies in the time series. That is a clue for where to look with regard to what is causing those dominant freqencies.
    The hypothesis is that CO2 is a dominant driver of climate. This study provides a test for that hypothesis, as the CO2-driver is already in the timeseries. All we have done is increase the amount of CO2 and if it is dominant we should see it in the near future. Just by looking at the graph one sees that a rapid rise of temperature has always been followed by an immediate rapid decline of the same magnitude. I think that should give pause to all of us, really. If that is where we are heading, I’m off to buy some more coats.

  17. I’m guessing they must have an exceptionally long historical record to support some, most, or maybe even all of this. Not confirm the early parts but at least support them.

  18. Not to worry, this is voodoo science. You can be assured, Earth will keep warming and polar bears will keep melting!

  19. crosspatch says:
    December 7, 2011 at 11:49 pm
    ……………..
    Yes, I did post it for you, but you wandered off to elsewhere. It’s more like 600, but analysis with less than 1 cycle available is very questionable.

  20. bill says:
    December 8, 2011 at 12:05 am

    I am inclined to treat this with some validity. So far I have seen similar analysis by two different people using two different time series of two different types (one using tree ring cores in Tibet and the other using the CET temperature record) and they both generally agree. Both analyses found similar period cycles in the data. Both analyses provide the same prognosis for what lies ahead. I think there is likely some validity to this. The chances of two completely different sorts of data from two completely different regions of the planet done independently by different groups of people present the same general result is beyond the realm of chance, in my opinion.

  21. You can check out who the authors ( LIU Yu, CAI QiuFang, SONG HuiMing,
    AN ZhiSheng, Hans W. LINDERHOLM ) for:

    Amplitudes, rates, periodicities and causes of temperature variations in the past 2485 years and future trends over the central-eastern Tibetan Plateau

    are and their status in the academic/scientific world, together with some of the
    citations they have in hand at:

    http://csb.scichina.com:8080/kxtbe/EN/abstract/abstract504775.shtml

    Not only was the study peer reviewed, but they did some of
    field work too !

  22. Matt: this is a multi-disciplinary Ijournal published by the Chinese Academy of Science. It is peer reviewed, has a high impact factor and an eminent editorial team. It incidentally has a very low self-citation score so carries a very low score on the toadyism index. That doesn’t mean the paper does not have flaws but the quality of the journal is not the issue.

  23. I wonder if these scientist could apply their methods to the questionable tree ring studies?

    As an aside, I am shocked that scientists could just publish without any concern for the damage that may be inflicted upon the ‘team’!! :-)

  24. M.A.Vukcevic says:
    December 8, 2011 at 12:10 am

    Thank you. Yes, I missed it. So there does seem to be a longer period signal, I “eyeballed” it a >700 years but as you say, the record isn’t long enough for any accuracy at that wavelength. The 60 year cycle seems to show up in many different records of all sorts, even in lake bed sediment core pollen surveys, the 60 year Chinese calendar, all sorts of things: http://hockeyschtick.blogspot.com/2010/04/more-on-60-year-climate-cycle.html

    This isn’t the first time that it has been noted.

  25. Larry Fields says:
    December 8, 2011 at 12:19 am

    “The regularity of 600-year temperature increases and 600-year decreases (Figure 3) suggest that the temperature will continue to increase for another 200 years, since it has only been about 400 years since the LIA.”

    Is this part: “about 400 years since the Little Ice Age a typo?”

    It looks as though the date range for the LIA and the MWP was different in China. (That’s OK–our side has often argued that there’s no such thing as a global temperature, but rather that regions have their own trends that are only loosely linked to one another.) The main point is that at roughly the same time as our MWP and other warming periods there were higher temperatures than now in Asia is the important thing.

  26. bushbunny says:
    December 7, 2011 at 11:07 pm
    ////////////////////////////////////////////////////////////////
    This report may influence chinese scientists and their political leaders. Reports such as this may be seen by the Chinese as a good reason not to get too concerned about AGW, and not to sign up to any world agreement unless it favours Chinese interests, ie., they get a dollop of cash, free industrial technology or otherwise assists in shifting the industrial power base their way from West to East resulting in their increased ecconomic might.

    Whilst I welcome this study and whilst the resultant past temperature trends seem to fit in with what we know about history, before one crows too much it is important to bear in mind that this is based upon proxy reconstructions. Proxies are at best a rough and ready indicator of a ball park figure, and tree proxies in particular are poor proxies for temperature. Ring size reflects the then prevailing growing conditions and as Bushbunny states there are numerous factors (in fact many more than listed by bushbunny) that influence prevailing growing conditions.

  27. Larry as far as I know that the LIA started sometime in the 14th Century and gradually on and off
    some years warmer than the last, but generally much colder with short seasons, and more snow and ice. But in the 18th and 19th century the Thames froze over and they had ice fairs. England and UK generally the LIA ended around mid 1850, and it started
    to get warmer gradually with some cold seasons. 1947 was an exceptional cold winter, and in 1963 the Thames froze as far as Windsor. But one good thing well in a way. They had poor wine
    harvests and England stopped growing grapes. But they turned the old presses into printing presses. So the impact on humanity was immense. There was a way eventually to educate the masses. Less wine, more thought, LOL. Prefer both myself.

  28. There’s this, too:

    http://www.arctic-frontiers.com/index.php?option=com_docman&task=doc_download&gid=242&Itemid=155

    So we can probably say that the 60-ish year cycle is NAO/PDO

    What is interesting in all of this (and now we get our tin foil hats) is if maybe some of these people knew this was coming. I mean, running paleo climate data through a spectrum analysis would be something one would think would have been done in the 1960’s. I wonder if they knew these cycles were going to peak at about this time and knew it was a great time to become rich and famous. Particularly Hansen. He was running around in the 70s telling people we were headed for an ice age if we didn’t stop burning coal. Then he changed to we are going to boil.

    I wonder if this also adds to their sense of urgency and there apparent desperation in trying to get major regulations passed now. The rhetoric certainly has become shrill. I wonder if they realize that they have actually already run out of time.

  29. Kasuha says: Kasuha says: December 7, 2011 at 10:51 pm

    Fourier analysis on time series may be a lot of fun but until physical background of identified cycles is demonstrated it’s not more than just playing with numbers with zero predictive potential.

    I’m sorry to see this faux argument keep on reappearing. It would be nice to see a whole post on the scientific propriety of working with significant correlations, whether or not they have explanations. A post to remind us that we still don’t really understand how gravity works, for instance, despite having an extremely high predictive ability in this area.

    This is a brilliant paper. Yes, it goes a long way to rehabilitate treerings as temperature proxies.

    However, I would like to see corroborative studies of treeline shifts from this locality. I still get the feeling that these may indicate longterm large shifts rather better.

  30. Matt says:
    December 7, 2011 at 11:48 pm

    Does Bull stand for bulletin or bullshit? – I mean, where’s the magic word? Is it peer reviewed, is this a respected publication outside China? You were furious about Muller, obviously, because you didn’t like the conclusion. And now? Obviously, this time you like the conclusion – but what about peer review?

    Is this this Matt?

  31. @ crosspatch and Vukcevic

    Has anyone attempted to compile a composite of the known cycles (i.e. AMO, PDO, sun cycles, etc) and see if there could be a correlation with regards to various cycles peaking at the same point in time and therefore causing 60 year, 100 year, 800 year, or whatever peak and troughs in the global temps? In other words, numerous amplication factors to highs (or lows) happening at the same point in time amplifying temp.

    My math expertise expired a long time ago so I’m just a puppy here now.

  32. Who cares about the climate, not NGO’s its about MONEY, always was, always will be. We have got to keep trying to stop them getting our cash for a false prophet (profit) sarc.

  33. Whether or not tree rings are a good proxy for temperature, they are a precise indicator of conditions which are beneficial for tree growth. From this it would not be difficult to conclude that those conditions have a similar impact on other plant growth, including food crop yields.

    I don’t think it is a big step from there to suggest that increased crop yields are good for the human race, thus whatever else tree rings show, they are a good proxy for human well-being.

    Can anyone suggest any holes in my logic?

  34. Much cleaner than the Hockey Stick I think. No discarding of data and replacing it with an unrelated data set (Hiding the decline + Nature Trick). No gratuitous PCA analysis. And I doubt we will find in a decade that deliberate deceit looks to have been involved.

    But still it involves a dubious metric — tree ring width. It uses a technology — Fourier analysis — that always provides an answer for any data assemblage but provides no indication (e.g. variance) about the quality of the answer. And we don’t really know what causes the “decline” that Jones was concerned about hiding and whether that decline is present in the Chinese data.

    Lots we don’t know. But certainly worthy of publication.

  35. crosspatch says:
    December 8, 2011 at 1:10 am
    There’s this, too:

    http://www.arctic-frontiers.com/index.php?option=com_docman&task=doc_download&gid=242&Itemid=155

    So we can probably say that the 60-ish year cycle is NAO/PDO

    What is interesting in all of this (and now we get our tin foil hats) is if maybe some of these people knew this was coming. I mean, running paleo climate data through a spectrum analysis would be something one would think would have been done in the 1960′s. I wonder if they knew these cycles were going to peak at about this time and knew it was a great time to become rich and famous. Particularly Hansen. He was running around in the 70s telling people we were headed for an ice age if we didn’t stop burning coal. Then he changed to we are going to boil.

    I wonder if this also adds to their sense of urgency and there apparent desperation in trying to get major regulations passed now. The rhetoric certainly has become shrill. I wonder if they realize that they have actually already run out of time.

    ========================

    crosspatch, I think you hit the nail on the head.

    That they were well aware of the 60 year cycle and pushed so hard for regulations and now that time has run out would fully explain the last ditch effort we are seeing now. It would also be close to proving the fraud in the global warming swindle.This has been my suspicion for the past year or so. Oh how I wish that would show up in an email exchange.

    The great swindle would be much easier to explain than the collective ignorance of these people.

  36. Finally! Tree rings you can believe in!
    Do Chinese tree rings track local temps (unlike Russian ones)?

  37. 1. How many trees did they analyse?
    2. What trees were they?
    3.Why are they better than bristlecone pine?

  38. eyesonu

    Joe D’Aleo has put together a composite PDO/AMO index curve and plotted it against US temperature records.

    I don’t know of anyone who has combined further cycles in models.

    I do know that Piers Corbyn has noted certain cycles on the centennial scale which combine solar and lunar factors, but as he runs a private company he doesn’t do academic publications.

    It’s certainly one of the key areas for climate modelling/prediction right now………..

  39. eyesonu says:
    December 8, 2011 at 1:16 am
    “Has anyone attempted to compile a composite of the known cycles (i.e. AMO, PDO, sun cycles, etc) and see if there could be a correlation with regards to various cycles”

    There is a clear pattern in the instrumental record of the past 130 years showing how the warming and cooling alternates at 30 year intervals (60 year cycle). You don’t need any ‘maths expertise’ to see this; the Woodfortrees site allows you to plot graphs highlighting this trend.

    http://www.woodfortrees.org/plot/hadcrut3gl/from:1880/to:2011/plot/hadcrut3gl/from:1880/to:1910/trend/plot/hadcrut3gl/from:1911/to:1940/trend/plot/hadcrut3gl/from:1941/to:1970/trend/plot/hadcrut3gl/from:1971/to:2000/trend/plot/hadcrut3gl/from:2001/to:2011/trend

    See how the temperature falls from 1880 to 1910; rises from 1910 to 1940; falls from 1940 to 1970; rises from 1970 to 2000 and then levels out or falls thereafter. If this pattern is maintained, we can expect cooling for another 20 years.

  40. bill says:

    December 8, 2011 at 12:05 am

    Why have the Chinese decided to issue this particular set of lies at this particular time?

    What sort of comment is this? Demonstrate to me that the “Chinese” angle has anything to do with it. “Issue” detracts from the fact that it was published. “Particular set of lies” implies they, the Chinese, have a whole set of lies. The term “set of lies” implies there are at least several lies being presented at this time. The word “lies” is a very provocative and serious and requires demonstrable proof that the what is being said is knowingly untrue. I’m waiting to hear why you are calling the Chinese multiple liars….Please explain.

  41. On that very first chart… of course you realize, they’d snip everything before 1800 and say ‘Look! Precipitouse rise in temperatures…!’

    Wait. That is EXACTLY what they’ve been doing…

  42. While the study of tree rings to determine historical climates is more climatology than climate science, it can provide reasonably accurate trends with a big enough unbiased sample..

    Caveat: That is as long as the members of the Team don’t get to manipulate (apply Mannian Maths, or something similar) to the original data.

    IPCC Fantasy 5 will undoubtedly ignore this in favour of the much beloved, and totally discredited, Hockey Stick.

  43. Thats just Tibet, i.e. local climate. The heroic deeds of Mann were global!!! Plus they are Chinese… under the pay of big coal and communism. /sarc

  44. Lucy S: I had the same thought, as soon as I saw the name, and the comment.

    It would not be surprising at all if this is the same Matt (alias “MattB” who haunts JoNova).

  45. A research paper that comes up with a result that one would expect- natural cycles rule climate. It is the cycle lengths that are not well known neither is the number of cycles that go back into history, ie. the very long cycles that we are ignorant about.

    Well done the Chinese.

  46. Pete Miller~ Funny you should mention mann. Regarding what we have heard about just inputting Noise into his model, I have to wonder: would the Chinese data, plugged into mann’s model, generate a hockey stick?

  47. I said this at BH too. I still don’t see what magic you use to turn tree rings into temperature proxies. Just because this study gives the “right” result doesn’t make it any more valid than other tree ring projects. Surely a tree ring is a blunt object, it will tell you whether the weather was nice ( in tree terms ) or not and that’s it.

    BTW @Bushbunny
    Your chronology is a little off. The 17thC appears ( for historians ) appear to be the years of real extremes, especially around the middle of the 17thC, when there used to be broiling summers and freezing winters.
    It was interesting to see the dramatic trough at the begining of the 14thC which coincided with the start of the LIA in Europe, though.

  48. Well it’s interesting; but I would quibble with their figure #3.

    Their Stage IV straight line fit, seems reasonable, and it magically has the same magnitude slope as the three previous stages, but clearly the I, II, and III straight lines are really lousy fits to the data.

    I do agree that the up down pattern is there, but they exaggerate the slopes in the first three to try and fool us into believing that the era since 1600 is just the same as earlier times, which it clearly isn’t.

    But I agree with their general conclusion; the whole thing is a ho-hum so what ! And 2485 years of tree rings is a bit better than one yamal stunted weed tree.

  49. “This is a brilliant paper. Yes, it goes a long way to rehabilitate treerings as temperature proxies.”

    It does nothing of the sort. We need to see the methodology, especially sampling practices and numbers. I will keep repeating this until the physical scientists get a glimmer: every tree lives within its own unique ecosystem. Sample sizes need to be very large and very carefully cluster managed in order to ascertain any extrapolated trend. In any event, all you will measure is a local regional response, if you can even get the signal noise out. To do this with any meaning at all, you need stable isolated larg(very large) stands of trees not within range of historical and modern day harvest, industrial and agricultural practices. Good luck finding those.

  50. Those who question the validity of this research because of the absence of a cause are missing the point. If one accepts that the data is real then the predictability of temperature fluctuations is startling irrespective of whether we know why it is happening.

    They have taken a 1200 year period to identify the main frequencies and generate the Fourier coefficients. They have then applied these coefficients to generate a prediction for a completely different period spanning the years 835 to 1980. One only has to look at the correlation between actual and prediction to see that the match up is just astonishing.

    My conclusion is that they are either right or they have manipulated the data in some way. I cannot really see that there is room for any other conclusion. My personal view is that they are right given that they have published the data necessary to allow other scientists to look for the same power spectrum and test their conclusions. They would not have done this unless they were confident. Mann et al please note.

  51. These are non-cooperative trees. Under Mannian standard procedure, such trees are to be walked outside and shot.

  52. No wonder the Chinese “ratf$%&ked” us accodering to ex Prime Minister Rudd after Cpenhagen. They are to much into realism on these things.

    And thank god someone is doing a Fourier Analysis instead of this statistical drivel about principal components. Given we live of a rotating planet with a large orbiting satellite and are part of a spinning and orbiting solar system with all this evidence of cyclical effects from sun spots to whatever , the idea that one would not go to a Fourier Analysis FIRST is simply mad or utterly incompetent as far as I can see. Me, I am and engineer who chases vibration signals and ocean wave spectra but what would I know?

  53. crosspatch says:

    December 8, 2011 at 12:28 am
    The chances of two completely different sorts of data from two completely different regions of the planet done independently by different groups of people present the same general result is beyond the realm of chance, in my opinion.
    Unless they produce an hockey-stick?

    Statistics isn’t my strong point, but in figure 1 the bottom SD curve doesn’t look right.

  54. bill at 12:03 am above:

    Bill,

    The journal date for the publication of the Liu, et al 2011 , sumaary was
    October 2011.

    If I’m reading the material correctly at:

    http://csb.scichina.com:8080/kxtbe/EN/abstract/abstract504775.shtmlt

    [Please be patient, this was very slow downloading for me numerous times.
    A traceroute showed the problem was with the servers at the far end (Asia)
    of which several were running slow.]

    the main study was originally submitted in March of 2011 and revised in August.

    The study went through an unhurried peer review and editorial process
    prior to publication in October.

    This was published long before the COP17 delegates were gathering… and Jo Nova
    brought it to our collective attention just now in December.

  55. A NEW WORLD ORDER

    Which societies usurp the aspirations of its citizens and are forcing them into penury with their industrial and energy policies, backed by government funded propaganda masquerading as scientific research and which society is striving to improve the lot of their masses with a healthy respect for industry and an even healthier respect for objectively conducted research, free from political dogma and control?

    This question for Matt and Bill.

  56. Great feeling for an author, who, with physics, for everybody transparent and understandable, calculated the 800 year (to be precise: the 790 year) cycle. Being validated with field reseach …great! See German Amazon.de : Book: ISBN 978-3-86805-604-4.
    History proves the 800 year cycle wordwide, even in the most remote areas of the world (such asTibet etc) and with above quoted physical calculations, that they really exist…. well folks, sit back for a couple more years and the Hockey-stickers will be the laughing stock of history soon in this very decade…..
    JS

  57. Matt says: “…what about peer review?”

    Peer review is worthless. That was understood before all the AGW-nonsense. The AGW-nonsense has in fact shown this statement to be, simply, true.

    There have been those who warned of Technocracy: which is pretty much that politics-ideology CAN and WILL turn ‘science’ into an Authority with pre-determined Determinations (from which certain actions necessarily must follow), for carefully selected ‘Issues’. Those people were well aware how things work in the echelons of power and influence, and that ‘science’ was oh so very bendable: so here you all are, oh so very surprised that your holy cow has given birth to a plague-ridden turd.

    Shall I mention Feynman? Go read his little speech again… and then dare try and tell me that ‘science’ will somehow magically end up perfecting itself AS AN INEVITABLE FACT. The practice of ‘science’ was, is, and will be subject to certain types of behavior and procedures (Feynman was EXPLICIT on this last point, AND the one before it) on the part of the ‘scientists': since these have not been followed, AT ALL, surely this outcome, which is that Science Is Dead, was inevitable? Surely.

    And then there are the hippies: most of you will not be aware of the pure, raw, corruptions that under-gird ‘Evolutionary Science’, but they too use ‘science’ as an iron hammer to bypass fact+logic+reason. ‘Settled science’ to blast pass the obvious need for such a thing as ‘proof’ in the face of incredible imPROBabilities – little mind-pictures of ‘POSSibilities’ are supposed to suffice – and do, to morons and uncaring dolts both. ‘Settled science’ to blast pass the obvious requirement for such a thing as falsifiability; how very unreasonable to expect ‘science’ to distinguish between ‘orderly patterns’ and ‘the Fact of Evolution’ – the outcome is, after all, settled. The very act of Interpretation itself is settled, and limited – all who disagree are Deniers: such people should be stripped of all credentials and cast out into the gutter… sound familiar?

    You all (how very few are not part of this) have blindly allowed MASSIVE corruption to flower in regards to ‘defending’ the ‘science’ of Evolution from those who are ‘anti-science’… and now you reap the whirlwind – generations of hippie-type ‘scientists’, who LIE as it suits them. Thanks to your pathetic weakness, that once great tool for the advancement of mankind, science, has been turned into a whore that is rotting to death in a ditch.

    ‘Science’ had early on become, necessarily, the Prime Dogma of Humanism, atheism, etc. Also necessarily, its acceptance has become the Central Dogma for modern POLITICAL Humanism. (Ever met an Atheist who was not also a rabid ideologue? No? So what does that tell you?) And since peer-review as zero ability to Withstand political and ideological influences, it has served quite nicely in promoting-and-Justifying every single fluff-brained hippie dream-thought ever envisaged. Another (obvious) truism: hippies have no moral Standard (inherently, Excepting being utterly selfish and demoniac, of course), therefore they tend, on average, to be without morals or ethics. And yet you are all ever to surprised when this particular snake rises out of the grass and bites you on the ass.

    I am not quite sure who is more worthy of contempt: the fools, or those who are surprised that fools do foolish (and consequently vile and murderous) things.

    How many more people must die in abject misery at the altar of Political Humanism? DDT is just one example. Just one. 40 MILLION dead, mostly children. Yet I am the insane fanatic who hates science. Yes I do, with because ‘science’ IS worthless, because ‘peer-review’ IS utterly dominated by political-ideology. Because I am sick of its murders, and sick of its lies.

  58. The first figure actually does show Mann’s hockey stick for the last 1000 years. Which is the time period over which he made his annalysis. It does not show a MWP but does show a LIA.

    Doesnt answer the question – are trees good thermometers?

    The Fourier analysis is very interesting and Iwould love to see links there to other cycles

  59. Bloke down the pub says:
    December 8, 2011 at 3:34 am

    “Statistics isn’t my strong point, but in figure 1 the bottom SD curve doesn’t look right.”

    Mine either. And actually, both sides of the SD curve look wrong. Shouldn’t the SD curves be equidistant from the mean? Unless they did it from the mean of the whole series rather than each data point.(Though I’m not sure I’ve ever seen it done that way) Maybe this isn’t a statistical analysis?

  60. I don’t know. My radar is still up on the validity of any tree ring study..and left wanting….? Maybe I’m being unfair…but it seems to me that producing a power spectrum analysis (one of many that might fit) is necessary I suppose – but not sufficient. I would have appreciated a causal justification for the cycles chosen – and would have started with those already known in nature (solar, ENSO, etc….)…..?

  61. Liu Yu, Director of Earth Environment Institute of the Chinese Academy of Sciences, was interviewed about his paper by the South China Morning Post (Dec 4, 2011):

    Where did you find trees more than 2,000 years old in a country with a long history of systematic logging? I need luck to find a tree more than 100 years old in the lowlands. But on some mountains of the Tibetan Plateau, where the altitude reaches up to 4,000 metres, I have run into forest after forest of Qilian junipers that have remained undisturbed for thousands of years.

    How does a tree survive in that kind of harsh environment for so long? The Qilian juniper is one of the oldest surviving tree species on earth. In the high altitude of the eastern Tibetan Plateau, where poor soil, little rainfall and low temperatures make it impossible for other trees to survive, the juniper has perfectly adapted to the harsh environment by growing very slowly. We recently found one that is close to 2,000 years old, but less than 8 metres tall. In the study of tree rings, slow-growing trees provide information on variations in climate over a long period. Qilian junipers grow only in China.

    Is the study of tree rings popular in China? Chinese researchers have studied tree rings for more than seven decades, and some scientists have produced original studies containing a trove of important data on the climate. But due to historical reasons, their research methods did not quite fit with international mainstream thinking, and therefore not widely recognised. Since the 1990s, as climate change has become a political and diplomatic issue, the study of tree rings has received increased government funding, allowing Chinese researchers to use the best tools and methods and produce well-received results.

    Are the field trips fun? To collect samples, we sometimes need to dance with death. At altitudes of more than 3,500 metres above sea level, my research team has to combat low air pressure, a lack of oxygen, headaches and sometimes life-threatening illnesses. The best Qilian junipers for our purposes often stand alone on a cliff, where they can be fully exposed to the elements. We have to watch our step when approaching such trees. Some researchers from overseas have slipped and died in less-perilous situations. Most virgin forests of Qilian junipers are in areas inaccessible by road, and are barely, if ever, visited by humans. The remoteness turned each of my more than 20 data-collection trips over the past 10 years into unforgettable adventures. Standing so high up, with an ancient tree, one has the opportunity to enjoy some of the most breathtaking landscapes on earth.

    Do you need to cut down a tree to take samples No, we do not cut down trees. Once a tree is selected, we use a long, fine tube similar to a chopstick to bore through the trunk and reach the core. It’s standard practice used by scientists for a long time and does not cause the tree any serious damage. In the laboratory, all the samples must be polished with sandpaper. The work is time-consuming because the samples cannot be used for measurement until they are smooth enough that, when put under a microscope, we can see a perfect outline of their cells.

    What do you do with the data? Using a set of scientific techniques, we measure the width of the rings and convert the variations into changes in annual temperatures. We have published two papers in the English versions of Science in China – Series D: Earth Sciences and in the Chinese Science Bulletin.

    What have tree rings told us about climate change over the last two millennia? Popular belief is that industrialisation has led to the fastest rate of warming witnessed by humans; that we are at the warmest time of the modern era; and that we are causing global warming by emitting carbon dioxide into the atmosphere. None of that fits the records in tree rings. In northern China, the warmest period occurred from AD401-413, which had an annual mean temperature 0.16 degrees Celsius higher than today’s. Other periods, including 604-609, 864-882 and 965-994 had temperatures higher than in recent decades. Our results are supported by historical documents from the period. Archaeological records in Loulan , Xinjiang , show that pomegranate, a fruit rich in vitamin C, was used as currency during the Eastern Jin dynasty (AD317-420). The fruit could not possibly have appeared in northern China without a climate much warmer than today’s. And we are not experiencing the most dramatic climate change in recent history, either. Over the past 2,485 years, the biggest climate change took place during the Eastern Jin dynasty. The period had two stages, with the temperature plummeting first and then soaring. In the warming period, the mean temperature [in the Tibetan Plateau region] increased suddenly from 1.66 degrees to 2.67 degrees in 30 years. In the cooling period, the mean temperature dropped to below that of the Little Ice Age [an abnormally cold period that lasted from about 1550 to 1850]. The coldest years, with a mean temperature of 1.38 degrees, occurred from 362-369, and the temperature was about 1.5 degrees lower than the mean temperature of the late 20th century.

    So what causes climate change? We believe that the sun and atmospheric circulations play a vital, if not decisive, role in this. The millennial cycle of solar activity determines the long-term trends of temperature variations. Almost all sunspot minimums [periods of sometimes several decades when sunspots become rare] correspond with low-temperature intervals. Meanwhile, atmospheric circulations affect temperature changes from decade to decade. To quote Professor Zhu Kezhen , the father of climate change studies in China: “The big changes in the earth’s climate have been controlled by solar radiation, but the small changes by atmospheric circulation.”

    Can tree-ring records tell us anything about the future? Our results show that the temperature continued to increase until 2006, and will now decrease until about 2068. After 2068, the temperature will increase again until 2088.

    Do you think your research will help Beijing gain ground in climate negotiations? I am a scientist, and I know nothing about politics. But the climate- change debate, in my opinion, has more political significance than scientific. Diplomats can sit at negotiating tables talking about carbon caps while scientists have not reached an agreement on the role of carbon dioxide in global warming. But political decisions must be based on sound scientific foundation, or they will be useless, if not dangerous.

    http://www.scmp.com/portal/site/SCMP/menuitem.2af62ecb329d3d7733492d9253a0a0a0/?vgnextoid=8ef931369d404310VgnVCM100000360a0a0aRCRD&ss=china&s=news

  62. Gosh I wonder how some of the psuedo-scientists on the AGW team are going to deal with this? Can they afford to ignore it? If the do they will be accussed of either cherry picking or rank racial bigotry.
    Good to see real science based upon real observations and not dodgy modelling of dodgy data.
    Why aren’t Western scientists doing this rather than trying to extrapolate a few sightings of Polar bears doing what Polar bears do into some doom and gloom prediction of the future?
    If that is the best that Western science can give us then maybe we deserve the decline in the West that is happening.

  63. Good on the Chinese – sure.

    How embarassed will we in `the free West’ be if it turns out that science in an authoritarian, communist state manages to turn out objective and correct analysis whilw efounder with politicised, agenda riddled rubbish.

    Where is the self respect of our once great scientific establishment.For how long are natural scientists in the West going to sit on their asses and not speak out against this disgraceful stacked deck, that `climate science’ has become?

    Disclosure: The Bear’s wife is Chinese. Guess that makes the Bear in the pay of evil sceptics, eh?

  64. no hullaballo no hype just data and the ability for others to see and check it out, appears to me that may actually BE science at work for a change?
    its probably spot on or closer than most,, I say that because NO msm has picked it up.
    whereas they immediately pounce on every halfassed panick and die pronouncements by the goracle and his menn
    this is one case where more research, would’nt be the usual cause for hilarity.

  65. matt a~ I have looked at all of the graphs very carefully. I see massive ups and downs, where do you see a long, flat line?
    Dare I ask what the ‘a’ stands for your name? I would guess it stands for [self-snipped]

  66. John Barrett says:
    December 8, 2011 at 3:08 am

    I agree – all that tree rings thickness show is that it was a good growing season; this often bears no relation to temperature. There are too many other variables that affect tree growth – don’t ask someone with a PhD, talk to any gardener.

    What these results show is that there are cycles in the climate between good growth conditions and poor growth conditions for that species of tree in Tibet.

    If climate ‘scientists’ want to claim they can tell temperatures from tree rings it’s simple – do a double blind experiment with tree sections cut during the instrumented period. The type of tree would be known but the date of the tree sections and the location they were cut from would be unknown to the experimenters. They would be required to quantify the annual temperatures from the tree rings to an accuracy better than 1DegC. As this experiment is so extremely simple to set up one can only assume that it has not been done because the treemometer proponents realize that their hypothesis would be falsified.

  67. Observer – thanks for that interview….. It had all sorts of wry comments re: ‘mainstream’ thought and ‘politics’ and importance of their own work. A Mann smackdown! Ha ha ha! ;-D

  68. Wow… Just Wow!!

    “NotTheAussiePhilM says: December 8, 2011 at 1:50 am
    Finally! Tree rings you can believe in!
    Do Chinese tree rings track local temps (unlike Russian ones)?”
    What a statement – boils down to: I believe that data – is that data valid !!!!!! all in a couple of lines!

    Magically treemometers are accurate in China but just garbage when in Russia.

    Wow.. Just Wow!

  69. Tree rings are still poor proxies for climate. Too many variables leading to soft conclusions.

    I would rather concentrate on the more important subject matter: who is funding the NGO’s and what is their agenda.

  70. “Fourier analysis on time series may be a lot of fun but until physical background of identified cycles is demonstrated it’s not more than just playing with numbers with zero predictive potential.”

    To which I would add that the FT of a 2400 timeseries is going to be dominated by modes with period 2400, 1200, 800, 600, 400… very nearly a priori — you’d have to have a rather special curve (one orthogonal to these modes by construction) in order for this NOT to be so. I’d be a lot more impressed if the mode amplitudes were not so obviously artifacts, if an UNUSUAL peak showed up somewhere.

    Two other observations. The MISSING peaks are the ones at 11 years and 22 years. Watt’s Up With That? Is Tibet completely immune to the straight up solar cycle, El Nino and La Nina variations in rainfall? Where are there peaks that might be associated with decadal oscillations in general — Arctic, Pacific both might be expected to contribute? The PDO — maybe — has a bump.

    A very few of the peaks do seem “close” to named solar cycles, but again the range works against one. Hallstatt (2300 years) is almost the length of the interval decomposed and hence is invisible. Suess might be there, but 210 years is almost an integer factor of 2400 and (I think) suspect as at least partly an artefact. Gleissberg actually does appear to be there, and although 30×80 = 2400, that’s out there far enough that I’m willing to believe that this might well be signal and not artefact/noise. I’m not claiming that these cycles are or should be causal, BTW, only that there is solar physics (known or unknown) behind at least some of these cycles and if one postulates a solar-climate connection it isn’t unreasonable to look for the signals in the climate reconstruction.

    In the end, though, I would have to completely agree — if predicting a chaotic timeseries were as easy as FT’ing the past and extrapolating the series into the future, I’d get rich on the stock market in no time at all. FT’s are useful to be sure, but one has to be aware that things peaks at certain modes (especially modes that are related to the interval length) are very likely to be artefacts. So I would have to say that I expect the extrapolative predictive behavior of most of these low lying (long period) peaks to be “low”, and expect most of the rest of the FT to be “noise”.

    There is a little-known paper by Demetris Koutsoyiannis called “Nonstationarity vs scaling in hydrology” that should be required reading for people who work in climate research. The beginning of the paper has nothing to do with actual climate research — instead he presents a short vignette on why this sort of analysis is difficult, especially why making egregious claims on the basis of a window onto a timeseries is dangerous. He shows a lovely picture of a simple “cosine variation” law (which can be interpreted as one of the fourier components, hmm, above) with white noise superimposed on it and shows how somebody looking at different windows onto a time series might interpret them. A short window on an upward trend gives you a (completely false) linear trend. A somewhat longer window from a minimum might fit a parabola or exponential (gasp — a runaway result, out of control!). It isn’t until the window is longer than a period that the cosine emerges. Or has it! Perhaps even this cosine is just local noise on a rule with a still longer timescale.

    This is why it is so very important to not only have the physics, but have the physics at a level that is predictive across the entire interval being fit in order to make any sort of conclusion. Without the physics, we don’t know the time scales that should be important, that should be modulating the timeseries signal. In the case of climate, we don’t know what the temperature “should” be if we tweak just one of the many knobs that contribute.

    This limits the conclusions that can really be drawn from this quite lovely study to the following:

    * Presuming a reliable link between tree ring width and temperature, not confounded by “noise” such as e.g. drought and wet cycles, early vs late spring cycles, cycles in the availability of nitrates (connected e.g. to thunderstorm frequency) OR assuming that these are all covariant with temperature in some average way, there is nothing particularly special about today’s temperatures in one part of China.

    * Several of the named historical warm and cold periods that are well-documented in at least some parts of Europe and North America were also warm or cold in at least one part of China.

    * To the extent that this is true, and to the extent that those named periods are quasi-synchronous with solar variations as represented in various proxies, it adds a bit more inferential support to the hypothesis that solar cycles are a major driver of climate change through physical mechanisms both in the sun and in the sun-earth coupling that remain obscure (partly because they are damned hard science to work out or measure!)

    * To the extent that one adds weight to the solar mechanism, one must remove it from competing theories or multivariate theories, as one cannot increase one effect without decreasing others to remain normalized to the observational data. Hence the “CO_2 dominant” hypothesis becomes a bit weaker, or if you prefer, the degree of dominance must be reduced.

    * Pure Bayesian reasoning (connected to the first observation above) suggests that the need to panic is significantly reduced by every study such as this one that shows no anomalous 20th century warming independent of all possible causes. To put it another way, if you didn’t know what the figure represented and were asked if there was any reason to think that the 20th century uptick (perhaps in the frequency of influenza deaths worldwide) was reason to believe that a crisis was immanent (human resistance to flu was breaking down), the answer would almost certainly be “no”. This is no hockey stick, indeed.

    rgb

  71. Liu Yu,
    Director of Earth Environment Institute of the Chinese Academy of Sciences,
    Would you be willing to take a student on board and show him a few `tricks` on how to do tree ring research ?,
    his name is Mike Mann, he currently lives in America and would probably love to do a bit of travelling right now.

  72. Observer says:
    December 8, 2011 at 4:25 am

    Liu Yu, Director of Earth Environment Institute of the Chinese Academy of Sciences, was interviewed about his paper by the South China Morning Post (Dec 4, 2011)….

    ….

    ….To quote Professor Zhu Kezhen , the father of climate change studies in China: “The big changes in the earth’s climate have been controlled by solar radiation, but the small changes by atmospheric circulation.”
    =====================================================================

    It will be most “interesting” if the CAGW types at CRU, etc. end up being ‘schooled’ by Chinese scientists….

  73. Observer:
    The SCMP interview was very interesting. However, I agree with others who advise caution until methods and validation data is available to verify that these tree rings are measuring temperature as opposed to “growing” conditions.

  74. The Zhou introductory piece, “The characteristics and regularities of the climate change over the past millennium in China’ (p.2985), for the 8 articles in the Chinese Scientific Bulletin makes the following statement:
    “The scientific argument on climate change is involved in the theories of the stochastic dynamics of a complicated climate system that are still only in early stages of development. The earth’s atmosphere interacts closely and nonlinearly with oceans, land surfaces, ice and snow, and ecology. Together, they all make up a complicated nonlinear climate system. Under the influence of a changing solar system, the earth’s climate has evolved in a complicated non-stationary process from its formation billions of years ago to its current status. We still know little about the characteristics, regularities, and mechanisms of climate evolution that is driven by external forces varying over time. Although the field of short-range numerical weather forecasts based on physical models is quite mature and serving society efficiently, climate methods prediction on the basis of the same physical models is less reliable and in fact no better than climate predictions based on empirical statistical methods.”

    Philip Stott was correct that climate change is governed by hundreds of factors.
    Trenberth was right too; it is a travesty that “we can not account for what is happening in the climate system”. But the travesty is not in our lack of knowledge, it’s just a travesty for Trenberth & Co.’s that they can’t simply pin it on CO2.

  75. “What these results show is that there are cycles in the climate between good growth conditions and poor growth conditions for that species of tree in Tibet. “…

    …and with some average synchronicity with similar good and poor conditions that affected trees elsewhere in the world, and that are also correlated with some other proxies or historical accounts of temperature.

    Don’t forget Bayes. Data like this doesn’t stand alone — it is linked by Bayes to other datasets.

    rgb

  76. To several,

    It does appear that that Mann’s Hockey stick is in there. It is odd though, that Mann’s stick actually drooped before he spliced it, and this one does not. To my mind it shows that the recent warming is not unprecedented.

    As for for the incorrect error range, I think someone deduced the error amount from zero instead of the plotted vale. If that was deduced from the plotted value, it would show a band the same shape as the plotted curve but broader, which is sort of what you’d expect if you did not increase or decrease error value over time. An easy mistake to make with long columns of seemingly random data in a spreadsheet IMO.

  77. The Institute of Earth Environment Chinese Academy of Sciences (IEECAS) was established in Xi’an in 1999, it is based on the Stay Key Laboratory of Loess and Quaternary Geology, CAS, which was founded through the efforts of Prof. Liu Tunghseng, An Zhisheng and others in 1985. http://english.ieexa.cas.cn/

    Jono – For information of CAS Earth Environment Institute on management of post-doctorate, such as application procedures, application form and application, etc, please contact Zhang Yingwen at zyw@loess.llqg.ac.cn.

    Matt – Liu Yu, male, born in 1963, doctor, research fellow, doctor tutor and Director of Earth Environment Institute, CAS; winner of National Fund for Outstanding Youth and the State Council’s special allowance for experts with outstanding contributions. Mainly in climatologic research of tree ring; published more than 70 Chinese and English papers; his research results of tree-ring stable isotope were appraised as the “Curve most reliable in Asia and favorably comparable with tree ring isotope results from other three major continents in the world” by international authoritative experts in the field; he chaired more than 20 topics, including Class II topic of major topic under National Fund Committee, key topic, outstanding youth fund and Class II topics under 973 Program of the Ministry of Science & Technology, etc. He also keeps close international cooperation with Sweden, US, Germany, Russia and Korea, etc. He chairs the Institute in all aspects, with specific duties on Party affairs, education, supervision and audit.

  78. Actually, thinking about the error bands, my last post is wrong. It is a pretty gross error if that is what happened. The error amount deduced from zero would be a flat line. They just reversed the sign on the +ve error plot, which is ludicrous. And peer-reviewed? By whom, I’d have top ask.

  79. Um, i don’t know, I think I still see a hockey stick at the end there …Just a little bit of a hockey stick….I think so… at the end there… see it?..Its there I’m pretty sure…

  80. This is a very telling email – 3234.txt

    From Richard Alley to Ed Cook?

    http://www.ecowho.com/foia.php?file=3234.txt&search=divergence

    “Unless the “divergence problem” can be confidently ascribed to some cause that
    was not active a millennium ago, then the comparison between tree rings from
    a millennium ago and instrumental records from the last decades does not seem
    to be justified, and the confidence level in the anomalous nature of the recent
    warmth is lowered. This is further complicated by the possible small influence
    of CO2 fertilization.”

    “I was just
    looking at some of the recent Mann et al. papers, and at the
    Osborn and Briffa paper from this year. In that one, as nearly as I can tell,
    there are 14 long records, of which 2 extend to 2000, 8 end in the early to
    mid 1990s, 1 in the early to mid 1980s, 2 in the early to mid 1970s, and one
    in the late 1940s. That looks to be a pretty small data set by the time you
    get into the strongest part of the instrumental warming. If some of the
    records, or some other records such as Rosanne’s new ones, show “divergence”,
    then I believe it casts doubt on the use of joined tree-ring/instrumental
    records, and I don’t believe that I have yet heard why this interpretation is
    wrong.”

    “But, I think you
    have a problem coming, that it involves the IPCC and particularly chapter
    6 and paleo generally, that I really should let
    Susan know what is going on (if you’ve seen all the increasingly publicly
    disseminated emails, you know the story).”

  81. JThoms says:
    December 8, 2011 at 4:48 am
    Wow… Just Wow!!
    “NotTheAussiePhilM says: December 8, 2011 at 1:50 am
    Finally! Tree rings you can believe in!
    Do Chinese tree rings track local temps (unlike Russian ones)?”
    What a statement – boils down to: I believe that data – is that data valid !!!!!! all in a couple of lines!
    Magically treemometers are accurate in China but just garbage when in Russia.
    Wow.. Just Wow!
    ====================================================
    Can I presume that you have no idea as to what the issue is with Russian temperature collection?

  82. Larry Fields says:
    December 8, 2011 at 12:19 am
    “The regularity of 600-year temperature increases and 600-year decreases (Figure 3) suggest that the temperature will continue to increase for another 200 years, since it has only been about 400 years since the LIA.”

    Is this part: “about 400 years since the Little Ice Age a typo?”
    ————————————————-

    I’m half way through “The Little Ice Age” by Brian Fagan – an excellent, albeit depressing read.

    His parameters are as follows:

    Little Ice Age begins ca. 1300
    Coldest period of Little Ice Age 1670-1710
    Little Ice Age ends ca. 1850

    So maybe a typo, or maybe a very rough approximation from the deepest depths of the cold.

    One more thing – has anyone applied Mannian statistics to this data set ?? Would love to see the result.

  83. Thanks Observer, that interview was gold. The original post is interesting too of course.

    I still think I’d take tree-rings over ice-cores as proxies, sure they are proxies, but if we had actual temperature measurements for the last 2000 years I reckon someone should be publishing them…
    As for being just curve-fitting (and it does look pretty good curve fitting). 1. It raises real questions about the effect of CO2 as a ‘driver’ of tibetan climate because the current warming over the time series is not unprecedented whereas the current CO2 apparently is. 2. If the curve fitting identifies cycles and a plausible physical mechanism exists for those cycles, you then have a predictive, and hence falsifiable hypothesis.
    As for lack of known short cycles, they’d be hard to pick up in a slow-growing, long-lived tree is my guess (you can have short, hi-res, or long low-res).

  84. Matt says:

    December 7, 2011 at 11:48 pm
    “Does Bull stand for bulletin or bullshit? – I mean, where’s the magic word? Is it peer reviewed, is this a respected publication outside China? You were furious about Muller, obviously, because you didn’t like the conclusion. And now? Obviously, this time you like the conclusion – but what about peer review”

    I do not think Lin Yu considers Mann, Jones, and the whole team peers. Did not one of the team members do a China study, but they lost the records<or their dog ate them or something.

  85. Observer says:
    December 8, 2011 at 4:25 am

    Liu Yu, Director of Earth Environment Institute of the Chinese Academy of Sciences, was interviewed about his paper by the South China Morning Post (Dec 4, 2011):

    IF this is a real interview, then this analysis was also based on a single tree:

    “…We recently found one that is close to 2,000 years old, but less than 8 metres tall…”

    Skeptics have severely criticized other tree-ring analyses based on small sample size (among other things), so if my interpretation is correct, should have a large dose of skepticism for this paper.

    Of course, if there are WUWT followers who have complete access to the paper and can tell us how many trees were used, I am happy to be corrected.

  86. bill says:
    December 8, 2011 at 12:05 am

    Why have the Chinese decided to issue this particular set of lies at this particular time?

    I see a comment like this and I immediately KNOW the Chinese are onto something important. Thanks, bill.

  87. Before claims like this can be made, I think these dendro-thermometers need to be calibrated, perhaps with individual instrumentation at each tree to show how they are affected by local environmental temperatures at various sites over a multi-year period. Perhaps this should be coupled with a study of how the other parameters affecting tree growth tend to correlate with temperature.

    I personally think isotopic analysis of the wood in each ring, particularly the O16 to O18 ratio would yield more reliable global temperature information.

  88. @ Peter Plail “whatever else tree rings show, they are a good proxy for human well-being.”

    Good point! Very good point.

    @ crosspatch and eyesonu “That they were well aware of the 60 year cycle and pushed so hard for regulations and now that time has run out would fully explain the last ditch effort we are seeing now. ”

    Yeah, that has been my suspicion as well. The push for CAGW has been so well coordinated, so well funded, so well supported by the media, and such a good investment for those who desire more money and power — at some point collusion and planning becomes the simplest and most reasonable explanation.

  89. The mathematician in me finds the power spectrum curve most informative. Those peaks in Figure 2 which can be declared to represent real cycles with 99% or greater certainty, the 2.0, 2.1, 2.3, 3 years, 100 years, 199 years, 800 years, and 1324 years help account for a LOT. The *causes* of these cycles may be debated until the next Ice Age, but the*data* indicates they are present and Mmust be included in any discussion of climate. The 100 and 199 year cycles I have personally observed in a power spectrum of the sunspot numbers, but my confidence was low because the sparseness of the data did not permit assigning a 99% confidence limit to their presence.
    Interestingly the 11+ year sunspot ‘cycle’ itself is not present, suggesting that the 100 & 199 year cycles may drive both climate and sunspots, but that the sunspots themselves do not drive climate per se. The physical mechanism of the 11+ year sunspot cycle appears confined in its direct effects to the sun, and does not significantly affect the earth’s climate directly.

  90. I cannot support the conclusions until I see the original data, the methodology used, the assumptions made and can replicate the results.

    I am old enough to realise that I can be fooled easily, especially by results which appear to confirm substantially my own beliefs.

  91. What trees ?, there are no trees. They were all cut down for fuel and can’t grow back for lack of Co2. We burn yak dung instead now but still can’t get the Co2 high enough to regrow them. We need more coal fired power plants. Then we can plant new trees and not cut them down.

  92. bill says:
    December 8, 2011 at 12:05 am
    Why have the Chinese decided to issue this particular set of lies at this particular time?

    If you convert the positive trends to 1s and the negative trends to 0s and feed it through an astable trigger and thyristor driving your christmas lights you get a beautiful display!

  93. “I am a scientist, and I know nothing about politics. But the climate- change debate, in my opinion, has more political significance than scientific. Diplomats can sit at negotiating tables talking about carbon caps while scientists have not reached an agreement on the role of carbon dioxide in global warming. But political decisions must be based on sound scientific foundation, or they will be useless, if not dangerous.”

    Yup. That does sound like a scientist.

    Certainly doesn’t sound remotely like Meltdown Mann.

  94. In the Conclusion: “However, there are still uncertainties in our understanding of climate change, and the concentration of CO2 affects the climate.”

    Too bad they felt that they had to mention a trace gas that has every indication of cooling climate rather than warming, if it has any detectable effect at all.

  95. Robert Brown says: “To which I would add that the FT of a 2400 timeseries is going to be dominated by modes with period 2400, 1200, 800, 600, 400… very nearly a priori — you’d have to have a rather special curve (one orthogonal to these modes by construction) in order for this NOT to be so.”

    FT would be useless if all it did was “find” subdivisions of the sample length. And the sample length is 2485, not 2400, and the full-length ‘cycle’ is definitely absent. It does contain cycles of 50, 37, and 30 years. Yes, chaotically trending (i.e. not white noise) data will generate false cycles that cease to maintain into the future – hence your stock market remark. The question is then, are these cycles false or are they real cycles being detected? If climate is a combination of both cyclic (e.g. PDO) and non-cyclic (e.g. volcano eruptions) events, then we might expect some of these cycles to be robust to a reanalysis of subsections of the data, whilst others should destabilise. In any event, your warning about the possibility of (but not the necessity of) artifacts is correct, and some of these cycles almost must be artifacts for physical reasons (the existence of non-periodic climate influences). I doubt that the prediction will come true to any degree of precision, although there are other physical reasons to expect some cooling.

  96. Observer says:
    December 8, 2011 at 4:25 am

    Thanks for posting that fascinating interview, it’s in sharp contrast to Mann’s recent letter in the WSJ. Has anyone seen something similar from Mann where he focuses on or explains the science, and not simply claim he is right?

  97. “Now some will argue that skeptics scoff at tree rings, and we do — sometimes — especially ones based on the wrong kind of tree (like the bristlecone) or ones based on small samples (like Yamal), ones with abberant statistical tricks that produce the same curve regardless of the data, and especially ones that truncate data because it doesn’t agree with thermometers placed near airconditioner outlets and in carparks. Only time will tell if this analysis has nailed it, but, yes, it is worthy of our attention.”

    Skeptics would be foolish indeed if they bought the simple minded claim that measuring tree ring width, or any other proxy, can tell us what temperatures have been for thousands of years. The reason is that proxy work has been non-empirical. No one does empirical study on the proxy item to determine how it changes under various environmental conditions. What must be done if proxies are to be used is that experiments must be conducted on individual proxies to determine their rate of change as various important elements of their environment changes. Anything less is non-empirical. Anything less is whistling by the graveyard. Briffa whistled by the graveyard and when his tree rings diverged from what he expected he was left entirely flat footed not knowing what had caused the divergence. Surely, this trap for the non-empirical scientist is clear as crystal and need not be debated again.

    Non-empirical proxy studies invite confirmation bias. Some climate scientists justify their claim that their proxies measure only temperature by selecting trees at the treeline of mountains. Then they say that the other variables have been minimized so only temperature is a variable and their study is objective. Is it not obvious that what they have done in fact is select proxies that maximize the impact on the study of the variable that they had predetermined to be most important, temperature, and minimized all other variables. That is confirmation bias writ large.

  98. MOre BBC lies

    http://www.bbc.co.uk/news/science-environment-16081214

    Male Polar bears always kill errant young ones – similar to lions. There is nothing new here but it fits the disgraceful lies that Polar Bears are threatened.

    Pravda or Hitler would be proud.

    [Moderator’s Note: Jeremy, this is off-topic for this thread. Next time please submit to Tips and Notes. -REP]

  99. Peter Plail says:
    December 8, 2011 at 1:36 am
    “Whether or not tree rings are a good proxy for temperature, they are a precise indicator of conditions which are beneficial for tree growth. From this it would not be difficult to conclude that those conditions have a similar impact on other plant growth, including food crop yields.”

    Only one is needed. Human management is incredibly beneficial for tree growth and it can be effective even when the climate has turned sour for plant growth in general.

  100. very interesting graph in that it shows the LIA was not a regional phenomenon, but global, as Tibetian trees were effected in some ways. We don’t know if the effect was temps, precipitation, or other, but there was an effect during that period of time. This disproves the “Team” assertion that the LIA was regional and therefore not useful in discussing AGW. Just another nail in the coffin of credibility for the Team.

  101. “Kasuha says:
    December 7, 2011 at 10:51 pm
    Fourier analysis on time series may be a lot of fun but until physical background of identified cycles is demonstrated it’s not more than just playing with numbers with zero predictive potential.”

    I believe you have this backwards. Science historically has predicted based on observation of repeatable cycles long before the cause was known. For example, people learned to predict the cycle of the seasons long before they learned the cause was the orbital tilt of the earth.

    Modern science needs to take a lesson from the past. We still don’t know the cause of gravity but we can predict the effects very well. What matters in science is prediction. Only after you have demonstrated that you can predict can you claim to know the cause.

    Even then, the cause of any event is subject to debate as new discoveries are made. There are still an infinite number of scientific discoveries waiting to be made. The tilt of the earth’s axis causes our seasons, but why is the axis of the orbit tilted? Isn’t the answer to that question the real cause of our seasons? Or was it the event that caused the event that caused the axis to be titled? Peel back the skin of an onion and you have another onion waiting to be peeled.

  102. “Beesaman says:
    December 8, 2011 at 4:28 am
    If that is the best that Western science can give us then maybe we deserve the decline in the West that is happening.”

    Climate science is not science. It is advocacy, politics and business wrapped in the garments of science. In this case CO2 has been used as a bogey man to frighten the masses into parting with the fruits of their labors to advance the interests of the groups involved. Data that would suggest that CO2 may not be a problem has been actively suppressed, as shown by the climategate emails.

  103. Robert Brown says:
    December 8, 2011 at 4:54 am

    There is a little-known paper by Demetris Koutsoyiannis called “Nonstationarity vs scaling in hydrology”

    ==========================

    The Koutsoyiannis paper seems to be available here: http://dx.doi.org/10.1016/j.jhydrol.2005.09.022 although the link doesn’t seem to match file name 2005JoHNonStatVsScalingPP.pdf I ended up with. If anyone has trouble, try clicking on the link in the web page at http://itia.ntua.gr/en/docinfo/673/

    I haven’t read it all yet, but 30 pages — including graphics — seem to be present

  104. JJThoms says:
    December 8, 2011 at 4:48 am

    Do Chinese tree rings track local temps (unlike Russian ones)?”
    What a statement – boils down to: I believe that data – is that data valid !!!!!! all in a couple of lines!

    Magically treemometers are accurate in China but just garbage when in Russia.

    Wow.. Just Wow!
    ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
    and Observer says: (Quoting an interview…..)

    Can tree-ring records tell us anything about the future? Our results show that the temperature continued to increase until 2006, and will now decrease until about 2068. After 2068, the temperature will increase again until 2088.
    ======================================================
    JJ is correct. I take little comfort in treemometers that kinda sorta tell us what we already knew. In our zeal to believe this treemometer reading extraordinaire, someone should actually check the veracity of his statement. Now, I haven’t looked at local Tibetian temps, so maybe that’s what he’s referring towards in his oddly specific prediction/backcast. 2007 was warmer than 2006…… 2010 treemometer data was probably not available…..so, there’s that….

    Can anyone tell me how we come to a reasonable assumption of what the low temps were while looking at the tree rings? Is there a negative ring growth which I’m not aware of? You see, when determining a mean like this, you need at least two numbers…. a high value AND A LOW! How does a tree ring determine the difference between 0°F and -40°F? It’s nothing but WAG. And we’re suppose to believe it was precisely 54.3° precisely 720 years ago. Whatever……

  105. All it needs is to be replicable. Show the homework so others can see what was done. You know, …. how science works. Then we go from there.

  106. OB-I think SM and JI would apply the same intellectual rigour to this paper that is extended in all of their endeavours. If you don’t think they are motivated by scientific curiosity and honest intention to extend knowledge then you haven’t not been reading much. If this paper is crap, they will say so.

  107. Boy, China was hit hard by the LIA and it was a long struggle to recover. I would think that nobody would want to see that again. Yet many bemoan and tear at their hair at such climate change. Bizarre! GK

  108. Observer says: December 8, 2011 at 4:25 am
    ……………..
    Do you think your research will help Beijing gain ground in climate negotiations? “I am a scientist, and I know nothing about politics. But the climate- change debate, in my opinion, has more political significance than scientific. Diplomats can sit at negotiating tables talking about carbon caps while scientists have not reached an agreement on the role of carbon dioxide in global warming. But political decisions must be based on sound scientific foundation, or they will be useless, if not dangerous.”

    The money quote from Dr. Yu.

  109. Significant in the Chinese finding is that the MWP and LIA were not confined to northern Europe as the hockey team and IPCC have repeatedly claimed.

  110. Just last week I did a thorough study reconstructing CET to 1538 from Historic records and comparing the results to Mann and Lamb.

    http://judithcurry.com/2011/12/01/the-long-slow-thaw/

    There are many good reasons why tree rings should not be seen as anything more than a general indicator of the growing conditions, including the fact that they only record any sort of signal during the growing season and a mean average accurate to fractions of a degree is impossible to discern.

    Just because we want to believe this study doesn’t mean it has any more credibility or accuracy than the Studies by Dr Mann et al.

    tonyb

  111. All that is needed now is to ring the data through Manniac’s computer model and we will end up with a hockey stick that ends going back in time.

  112. Kasuha says:
    December 7, 2011 at 10:51 pm

    Fourier analysis on time series may be a lot of fun but until physical background of identified cycles is demonstrated it’s not more than just playing with numbers with zero predictive potential.

    I agree that Fourier Analysis can be quite misleading when you are dealing with something other than a continuous signal. Having said that, their highest amplitude signal has a period of 110 years. It repeats 22 times in the 2500 year window. The second highest amplitude signal is 199 years which repeats 12 times in the window. They probably aren’t spurious.

  113. ob says:
    December 8, 2011 at 12:57 am

    i’d love to know what mcintyre and jeff id think about that reconstruction. guess they would debunk it.
    well they would debunk it if the people that did this used bad science or made major mistakes. they look at things to see if it is scientifically valid or not if not they call it out.

  114. Kasuha says: Kasuha says: December 7, 2011 at 10:51 pm

    “Fourier analysis on time series may be a lot of fun but until physical background of identified cycles is demonstrated it’s not more than just playing with numbers with zero predictive potential.”

    Fourier Analysis is but one of many tools, that attempt to understand complex systems & predict future directions. The climate system has yet to be completely understood, and use of different tools aid to that understanding.

    Below is a comparison between Fourier & Empirical Mode Decomposition filtering, using the CRU data. Note there seems to be very good comparison in the results, by two very different mathematical.methods.

    http://www.4shared.com/photo/2foIw4k7/CRU-Fig-6a.html

    However it might be worthwhile to look at Signal Conditioning literature. The IEEE has a designated Group relating to that area. Or you can pick up a copy of “Measurement of the Power Spectra”, Blackman & Tukey, for a basic understanding of the Fourier methods, and Applications.

    A side note, was that Drs. Norbert Wiener & Charles Draper worked together, using Fourier methods, to develop the Navy MK 14 gun sight during WWII. This later morphed into a A/C gun sight (B-29, F-86)..

    As far as use of Fourier methods in the stock market, check out the TradeStation package, for starters.

    .

  115. Take a look a my graph at:

    http://astroclimateconnection.blogspot.com/2010/10/1470-year-do-events-transition-from.html

    Using a much longer ice-core record – The last two (-6 and -7) and next (-8) 1470 year Dansgaard–Oeschger (D.O.) warming events STARTED at:

    800 B.C. – with temperatures reaching maximums around 600 B.C. (200 year rise)
    680 A.D. – with temperatures reaching maximums around 1100 A.D. (400 year rise)
    and 2150 A.D.

    In addition, there are secondary warm peaks at 200 A.D. and the present.

    In the Northern Hemisphere, they take the form of rapid warming episodes, typically in a matter of decades, each followed by gradual cooling over a longer period [typically a few hundred years].
    Wikpedia] http://en.wikipedia.org/wiki/Dansgaard%E2%80%93Oeschger_event

    Figure 4 of Liu Yu et al.’s paper shows that the 1324 years long term warming events peak at:

    680 B.C. – with long-term temperatures reaching maximum maximum 350 B.C. (~ 350 year rise)
    620 A.D. – with long-term temperature reaching maximums around 920 A.D (~ 300 year rise).
    and 2200 A.D. [obtained by extrapolation of their period)

    Other than the roughly 100 year shift, I suspect that the 1324 year cycle that Liu Yu et al. (2011) are finding in their truncated tree ring record is really just the is the 147-0 year DO phenomenon.

  116. Sorry, this comment in my last post:

    Figure 4 of Liu Yu et al.’s paper shows that the 1324 years long term warming events peak at:

    Should read: Figure 4 of Liu Yu et al.’s paper shows that the 1324 years long term warming events START at:

  117. I’m sure that the Team will roll out a “peer-reviewed” study in a few weeks attempting to refute this study. It seems to me that the only way they can try to refute this is to question the accuracy of “treemometers” which will cast doubt on the Mannian hockey stick. The Team’s other alternative is to ignore it. I can’t wait to see what they do (or don’t do).

  118. I’m only a highly interested civilian when it comes to the study of global climate. But, it has always seems logical that cycles within cycles would dictate global climate. Starting with the sun and then adding things like the “Chandler wobble.”

    Is there any research into the length of the cycle of the migration on magnetic north? This appears (to me) to be the best measure of the earth’s wobble.

    Magnetic north was fairly stable for decades (centuries?) at it southern extreme and now is moving quickly toward Siberia. Will it reach a southern extreme and stay there for decade or centuries?

    Could this be the 1324 cycle? The NH/world warmer when magnetic north is in Canada and colder when it is in Siberia? With relatively quick transitions in between the two cycles….

    I wish I had the proper training to tackle this project myself…all I have is a hypothesis.

  119. Hello – I applaud Mr. Brown’s analysis. Will someone e-mail this to the IPCC & the 12,000 freeloaders at COP17. Another day of discovery at WUWT!

  120. The second paper Liu Yu referred to is:

    Annual temperatures during the last 2485 years in the mid-eastern Tibetan Plateau inferred from tree rings
    LIU Yu, AN ZhiSheng, Hans W. LINDERHOLM, CHEN DeLiang, SONG HuiMin, CAI QiuFang, SUN JunYan & TIAN Hua

    Science in China Series D: Earth Sciences
    Received July 25, 2008; accepted December 22, 2008; published online February 3, 2009

    http://cadata.cams.cma.gov.cn/nianlun/upfile/China%20Science.pdf

    Supported by National Natural Science Foundation of China (Grant Nos. 40525004, 40599420, 40890051), National Basic Research Program of China (Grant Nos. 2007BAC30B00, 2004CB720200, 2006CB400503) and the Swedish International Development Cooperation Agency (SIDA, Grant to Hans W. Linderholm).

  121. So this Tibet record shows the “MWP” happened before 1000AD

    Yet the Central England Temperature record derived graph shows the MWP happened after 1000AD

    Explain that one skeptics.

  122. I have to agree with Matt … if this study showed an unusual warming in the 20th Century this blog would be tearing the paper to shreds lol

  123. Kasuha said: Fourier analysis on time series may be a lot of fun but until physical background of identified cycles is demonstrated it’s not more than just playing with numbers with zero predictive potential.

    Lucy S. replied: I’m sorry to see this faux argument keep on reappearing.

    But actually, it’s a correct argument. Fourier spectral analysis assumes that the data record for the window size represents a periodic function with mean value c_0. It therefore excludes by assumption the possibility that mean temperature could change to some other value outside that window. It assumes that climate — long term climate — does not change over the window.

    That said, this paper is important because it puts forward a hypothesis to compete with AGW: that increasing temperatures really *are* caused by natural variability. This places a greater burden on Mann et al to falsify this hypothesis if they are to win the argument.

  124. It’s interesting how well this matches what we know from historical records from Europe. I especially noted the very steep drop from ca 1550 to 1600. The 16th century was very warm in its first half, with some of the warmest summers ever in Europe, but the climate cooled dramatically in the second half of that century.

  125. Of course people here fail to talk about the sample depth in the W3 and W4 warming periods.
    See figure 4. The sample depth there is Less than Yamal.

    reading the paper helps.

  126. nomnom says:
    December 8, 2011 at 8:55 am
    Started at 900ad, ended around 1350ad. Just as the graph you posted says. Before and after. See? Or were making a joke?

  127. nomnom says:
    December 8, 2011 at 8:55 am

    So this Tibet record shows the “MWP” happened before 1000AD

    Yet the Central England Temperature record derived graph shows the MWP happened after 1000AD

    Explain that one skeptics.

    The Medieval Warm Period is portrayed differently depending on what proxy you are looking at. Liu’s graph shows a sharp peak just before the year 1000. It is similar in that respect to the graph produced by: Esper, E.R. Cook, and F.H. Schweingruber (2002). “Low-Frequency Signals in Long Tree-Ring Chronologies for Reconstructing Past Temperature Variability”. Science 295 (5563): 2250-2253.

    There are lots of proxies. They don’t agree very well. Don’t get your shirt in a knot by trying to read too much into them. Historical evidence and proxies tell us that there probably was a Medieval Warm Period. It may have been warmer than it is now. That’s all we can say with much confidence.

    http://en.wikipedia.org/wiki/Medieval_Warm_Period

    p.s. I was a warmist until Mann tried to erase the MWP; that made me sit up and pay attention to the science.

  128. steven mosher says:
    December 8, 2011 at 9:20 am

    Of course people here fail to talk about the sample depth in the W3 and W4 warming periods.
    See figure 4. The sample depth there is Less than Yamal.

    reading the paper helps.
    ==============================================
    lol, only if one believes in fairy tales and unicorns. Until someone explains how we can come to know the low of the temps that aren’t expressed in the rings (but inferred?) there’s no reason to waste any more time on it than what already has been. One hand clapping stuff.

    But I agree, this is every bit as valid as the studies that have the Yamal series in it.

  129. Matt says: “Does Bull stand for bulletin or bullshit? – ”

    If you knew anything about science, you would not find it necessary to ask that question.

  130. Re: “And thank god someone is doing a Fourier Analysis instead of this statistical drivel about principal components. Given we live of a rotating planet with a large orbiting satellite and are part of a spinning and orbiting solar system with all this evidence of cyclical effects from sun spots to whatever , the idea that one would not go to a Fourier Analysis FIRST is simply mad or utterly incompetent as far as I can see. Me, I am and engineer who chases vibration signals and ocean wave spectra but what would I know?”

    This whole CAGW nonsense just makes me grind my teeth. I thought for sure that this *must* have been done (Fourier) and that it came up empty. However, I was on the verge of dragging out my textbooks and doing it myself because it only makes sense and since they got everything else wrong, maybe they messed this up too. I guess they did.

    My experience with real world data is that signals work just the way we see here. I think it is likely to be real. I expect this will be replicated and confirmed. Once this has been shown to match up with other data sets, we will have about as good an answer as we are going to get. The rest of the short term variability is likely not predictable except for very short term weather prediction as we have it now.

    The CAGW hypothesis does not pass the ‘smell test’ in many different ways. I never gave it any credence at all. It was not until Climagegate that I paid much attention to it. It is nonsense on its face. Since then, though, I have done a little digging and followed CA/WUWT/JoNova for the past couple of years. This particular thread and its comments that I am responding to here is a nice little view on the problem. People have said that they don’t trust the Fourier analysis. WTF? This is absolutely the ideal circumstance to do such a thing and it is plain that it works. Fourier analysis does not and cannot attribute causes to the signals. That has no effect at all on its predictive power as can be clearly seen in the paper under discussion. The analysis predicts that those are the component signals. Next steps are to identify the underlying causes and I would predict, as implied by the posting I quote above, that they will be ‘cyclical’. The obvious things to investigate are things that periodically affect the light we get from the sun. Seems to me that includes stuff like gravitational effects on planetary orbits.

    I quoted the comment above, because it expresses a sentiment similar to mine that the CAGW analysis is simply illiterate. Where do you start? McIntyre was, so I understand, immediately aware that something was wrong when he saw the ‘hockey stick’. Me too. The curve did not look like anything I see in real data sets. A brief inspection of what is known about this stuff shows this one curve in conflict with just about everything we know. You don’t even see the hockey team themselves promoting this original ridiculous graph any more, even though they claim it was fundamentally correct. What they are showing in places like Wikipedia now, though still misleading, is closer to reality and contrary to their claims that the original hockey stick is vindicated, their new ‘hockey stick’ is not nearly as pathological as the old one. In some ways, the original ‘hockey stick’ was “not even wrong”. It was incoherent.

    I have not done a fit to the original curve, but eyeballing the original hockey stick blade, the original has been refuted by the last decade of empirical data as supplied by the planet itself. Would it not be considerably warmer already if they had been correct? There is no reasonable defense of the original, but the alarmist camp persists.

    Why would the alarmists keep going back to ‘warmest decade on record’ as if this is somehow remarkable? That is the way sinusoidal curves work. If we were near the high point of a sinusoidal curve we would expect exactly what we see. In fact, were we still climbing the curve, we would be expecting to be setting new highs constantly. The fact that we are not is an indication that we are near the top or even past the top and on the way down. This is absolutely the commonplace situation that anyone with a bachelor’s degree in a real science or engineering or even pure mathematics would expect. The ‘climate scientists’ must have missed a few classes or be fibbing. Likely both.

    The ‘hockey stick’ graph was wrong. Similarly, the ‘hide the decline’ graphs are wrong and just as obviously so. In fact, the error/deceit is even more obviously wrong on both scores where it has been criticized. You can’t honestly stitch a second data set measuring something else on to a graph. I realize that their data is sketchy, but this does not improve it in any way. As a whole, the spaghetti graph is absolutely dishonest. The addition of different data is wrong, but you can maybe understand why people would be confused by the rationale provided. The deletion of the data at the end of the set being graphed is wrong, at least at an undergraduate level and I doubt even a good high school would tolerate it. My old one wouldn’t. Choosing end-points that you know or should know are not appropriate for the thing you are illustrating is also dishonest. Putting everything together in a single graph and pretending that the monster you have created is a result of the underlying data is academic fraud. Unless and until the perpetrators are called up on the carpet for this, it besmirches the entire scientific enterprise. If you are involved in ‘science’, your reputation is taking a hit over this.

    There have been many references to the old chestnut “if you torture data long enough, eventually it will confess”. If you keep re-choosing starting points and end points and do things like the IPCC’s mutant math, you get howlers like this: “The linear warming trend over the last 50 years is nearly twice that for the last 100 years”. If you look at the treatment of the topic at WUWT (http://wattsupwiththat.com/2010/04/12/the-new-math-ipcc-version/), it is plain that the ‘scientists’ at the IPCC flunk high school math. The hockey team specializes in misleading half-truths and I find it impossible to attribute all of that to incompetence. To be sure, they are incompetent enough to think that their sophistry is convincing to educated non-experts. It clearly is not. However they can’t consistently choose the mistakes that support the lie without being somewhat committed to the lie itself.

    When you look at real data that contains a real signal, the signal is fairly easy to find and not very ambiguous. There *is* a signal in the climate data and the signal looks, I expect, very much like the paper under discussion (Lui et al 2011). Rather than some arcane sequence of ‘torture’ a la Michael Mann, Lui et al have done what I would do and what my engineer friend above would do FIRST and they appear to have gotten an excellent match to the data with a predictive fit that I find convincing. Real data and real data analysis looks like this, not like the ‘hockey stick’ or the ‘hide the decline’ graphs.

    I apologize for the long TL/DR rant covering ground covered over and over and OVER by the skeptical community. Like our engineer friend above (note: I don’t know any non-climate-skeptic engineers), I find the analysis or lack thereof by ‘climate scientists’ unconvincing. Actually, I find it irritatingly witless.

    The Lui et al paper is a bracing breath of fresh air and LONG overdue. This paper may well mark a turning point in this dreadful political episode. Even for non-interested people with a technical background, this must be infinitely more compelling than ‘CO2 forcing’ pushing climate to a catastrophic tipping point.

    The CAGW ‘climate science’ climate zombie has proven extremely adept at popping nails from its coffin, but I have a good feeling that this one may stick.

  131. This is scary. Feeding 6 billion people requires warmer, wetter weather with lots of CO2.

    Just look at the graphs and compare the dates of the cool periods and the warm periods with economic boom and bust periods of the past.

    If you want to read more, try Climate, History and the Modern World by H.H. Lamb. 2nd Ed. I have both 1st and 2nd.

    During the cooling around the mid-1970s, Lamb thought an ice-age might be coming but in the 1990s decided that the Earth would continue warming. So he is no more reliable than anyone else about the future.

    But about the impact of climates of the past he was a world class expert and well worth the read. The book sells for a ridiculous price on Amazon, but libraries can order it on inter-library loan.

    To give you an inkling: Lamb describes the hardship caused by the Little Ice Age in Europe. Iceland was completely ice-bound for 2 years making it impossible to get the fish people needed to survive.

  132. btrower says:
    December 8, 2011 at 10:26 am

    I wish I could rate comments because that one would get a 10.

  133. This will either be a resounding blow to AGW or “Chinagate”. We’ll see as the dust clears. This paper will be beaten to a pulp or become an icon or both.

  134. steven mosher says:
    December 8, 2011 at 9:20 am

    Of course people here fail to talk about the sample depth in the W3 and W4 warming periods.
    See figure 4. The sample depth there is Less than Yamal.

    The fact that the SAME pattern emerges from analysis of the CET data and others have found some of the same patterns in yet OTHER data http://hockeyschtick.blogspot.com/2010/04/more-on-60-year-climate-cycle.html says there is something to this.

    Can someone run an analysis on the Blue Hill Observatory record?

  135. The Other Jeff says:
    December 8, 2011 at 9:13 am

    “But actually, it’s a correct argument. Fourier spectral analysis assumes that the data record for the window size represents a periodic function with mean value c_0. It therefore excludes by assumption the possibility that mean temperature could change to some other value outside that window. It assumes that climate — long term climate — does not change over the window.”

    Well said. Surely, one thing everyone should have learned from the Hockey Stick nightmare is that tree ring width is not a linear function of temperature. Yet everyone calling himself a climate scientist proceeds as if it were. Climate science rests on a Uniformitarianism, the assumption that nature is uniform, that has not been practiced by genuine scientists since at least the 18th century.

  136. Pardon me for being very direct, but something very important about statistics needs to be understood by all. You cannot go out and collect measurements of whatever, fail to do the empirical work that shows that the individual measurements are sound, then expect your statistical work to make up for the empirical work that you did not do. The principle is parallel to GIGO. I recommend calling the principle “NEINO” for “non-empirical in non-empirical out.”

  137. nomnom says:
    December 8, 2011 at 8:55 am

    So this Tibet record shows the “MWP” happened before 1000AD

    Yet the Central England Temperature record derived graph shows the MWP happened after 1000AD

    Explain that one skeptics.

    Tree rings measure only June/July temperatures. Maybe THOSE peaked in THAT location earlier. A tree ring series in one region can not give a signal for GLOBAL climate, only the climate in that location and only for June and July. There is still room for regional variation due to changes in storm track, etc. Also it could be there was a rainfall anomaly prior to 1000. One thing I have learned is that the ITCZ and monsoon rains tend to also track with the LIA (and MWP). So it could well be that they got increased precipitation in that location before the MWP temperatures peaked. But the fact remains that the SAME signal(s) in those data appear in other data as well.

  138. commieBob says:
    “There are lots of proxies. They don’t agree very well. Don’t get your shirt in a knot by trying to read too much into them. Historical evidence and proxies tell us that there probably was a Medieval Warm Period. It may have been warmer than it is now. That’s all we can say with much confidence.”

    The medieval warm period cannot be in different periods. Otherwise it isn’t a medieval warm *period*.

    If we have one graph with a warm period from 800AD-1000AD and another with a warm period from 1000AD-1200AD they can’t both be cited as supporting a single “medieval warm” period. Yet that’s exactly what the CO2science site does.

  139. crosspatch says” “Tree rings measure only June/July temperatures. Maybe THOSE peaked in THAT location earlier”

    What if the two periods simply weren’t warm at the same time? Ie no global medieval warm period.

  140. Well said. Surely, one thing everyone should have learned from the Hockey Stick nightmare is that tree ring width is not a linear function of temperature.

    The same analysis was run on a THERMOMETER series in the UK with the same result. See the link in the early comments … nevermind, I’ll post it here:

    http://www.vukcevic.talktalk.net/CET-NVa.htm

  141. crosspatch says:
    December 8, 2011 at 11:10 am
    ……..
    Tree rings measure only June/July temperatures. …….

    Tree rings do not ‘only measure temperatures’.

    All tree rings show is the growth rate of the tree over that year. Provide water, nutrients, sun and a slightly cooler temperature – and you get a nice fat tree ring. Provide drought, low nutrients, obscured sun and hot temperatures – and you get an emaciated tree ring.

    A challenge – run the validation experiment I proposed above (http://wattsupwiththat.com/2011/12/07/in-china-there-are-no-hockey-sticks/#comment-822884 ) show that it is possible to quantify the annual average temperatures accurate to 1 degC using tree rings using a double blind protocol. If the experiment shows that it is not possible to quantify temperatures from tree rings, then all papers using tree rings as proxies for temperatures should be withdrawn.

    This is what scientists and engineers would do.

  142. “Explain that one skeptics”.

    But the best thing about climate science is, you don’t have to explain anything!

    Cherry picking is also legitimate. Hockey Stick or Tibet, have to think about that one. I asked Ted, our Tibetan terrier, but he went for option 3, the sausage.

    If they release their data and source code perhaps that will encourage Phil to have another look on his desk.

  143. I think there’s a cut-and-paste error. Instead of
    The largest Figure 6 Temperature comparison between the forecast and observation data taken from seven stations on the central-eastern Tibetan Plateau (seven stations: Delingha, Dulan, Golmud, Lhasa, Nagqu, Dachaidan and Bange). amplitude and rate of temperature both occurred during the EJE, but not in the late 20th century.
    I think it should read
    Figure 6 Temperature comparison between the forecast and observation data taken from seven stations on the central-eastern Tibetan Plateau (seven stations: Delingha, Dulan, Golmud, Lhasa, Nagqu, Dachaidan and Bange).
    and
    The largest amplitude and rate of temperature both occurred during the EJE, but not in the late 20th century.

  144. This analysis was also done with the temperature record from the UK (CET) with the same results. It is not just tree ring data that shows these cycles. See the link early in the comments.

  145. Liking the results is no reason for accepting the logic.

    I’m very wary of temperature proxies, especially tree rings. I think that any part of the findings should be regarded with extreme caution unless there is at least a known mechanism and independent corroboration.

    Thus, for example, when it says in ‘Conclusions’ : “The millennium-scale cycle of solar activity determined the long-term temperature variation trends, while century-scale cycles controlled the amplitudes of temperature.“, there is I think no known mechanism for either of these cycles, so this conclusion has to be treated with extreme caution. I am not even sure what the last part means (it seems to indicate that the century-scale cycles controlled their own or others’ amplitude. If it simply means that cycles were added together and sometimes their peaks coincided, sometimes not, then to my mind it was worded strangely.)

    Alan Clark of Dirty Oil-berta says: “It sets-out to destroy the hockey stick“.

    I hope it doesn’t, it should just be trying to find out about historical temperature.

  146. nomnom, there is ample evidence of the MWP and LIA, not just in Europe but also in Africa, the Middle East and even South America. The ONLY people that don’t show one is Mann et al.

    The now-discredited “hockey team” are the only people on the planet that DON’T show a MWP, they are the outliers.

  147. And we can point to the temperature response since 2000 to show that the analysis apparently does have some predictive pattern. The tree ring survey does not contain data for those years yet the resulting waveform accurately depicts what we see in actual observations. In other words, unlike the now-discredited hockey stick hypothesis, this output is validated by actual observational data.

  148. crosspatch says:
    “nomnom, there is ample evidence of the MWP and LIA, not just in Europe but also in Africa, the Middle East and even South America. The ONLY people that don’t show one is Mann et al.”

    The original hockey stick showed the period 1000AD-1200AD to be about 0.2C warmer than the little ice age and Mann 2008 puts it at about 0.4C, hence it did show a medieval warm period. It just wasn’t as warm as some people wanted/assumed.

  149. nomnom,

    Your chart shows global temperature going up a full degree Centigrade in a short time. Where did that chart come from?

  150. Matt says:
    December 7, 2011 at 11:48 pm

    Does Bull stand for bulletin or bullshit? – I mean, where’s the magic word? Is it peer reviewed, is this a respected publication outside China? You were furious about Muller, obviously, because you didn’t like the conclusion. And now? Obviously, this time you like the conclusion – but what about peer review?

    How about using your own brain? And real science. Instead of futilely trying to defend your pre-Enlightenment Postnormal Religion? Muller concludes everything and he concludes nothing, by his own admission. “Perception is reality”, as usual.

    Communism never works, Boy. The Chinese know that, or at the least that they shouldn’t use your “fear and trembling” energy scarcity scare to achieve your Dear Leader’s hallowed “sickness unto death” Utopia. Do you need “peer review” to know that?

    You are the one who stands for fake. Boy. So the real question is, what are you going to do about it?

  151. M.A.Vukcevic says:
    December 8, 2011 at 11:52 am

    I have a suggestion for an experiment.

    Run your analysis on CET only to 1990. Now plot the composite wave and continue it past 1990. Now plot on that composite only temperatures AFTER 1990 which were not part of the analysis. That should give some idea of any predictive skill. Now do the same for another record. I suggested the Blue Hill Observatory as it is the longest continuous record and it was done by skilled observers. It would be the record I would put most trust in for accuracy in the US.

    Another note about these cycles: depending on what their activation mechanism is, they could show different (or opposite) response depending on their location. Lets imagine there was some correlation with Markowitz Wobble (a roughly 30 year cycle). This would be expected to show up most strongly in records the farther North one goes as it would potentially have more impact on insolation in the North than in the tropics. So the relative strength of the various signals can vary according to region of the planet. If there is movement of weather patterns such as the ITCZ with the 800 year cycle, it might have a profound impact in one area and much less (or opposite) in another.

    So the energy distribution among the various cycles found might be different in different regions (or even hemispheres) of the planet and the cycles could be out of phase between locations. This is one reason I do not favor creating ensemble sets where several data sources are added to create a composite. I would rather favor running the analysis on individual data sources and comparing the result. If you create an ensemble and attempt to run the composite signal of that ensemble through a “notch” filter to obtain, say, the 60 year cycle, maybe that doesn’t work if the signal is there but out of phase between members of the ensemble and they cancel. A slight shift of the monsoon can have a rather dramatic impact, particularly in mountainous areas with rather severe “rain shadows”. Growing conditions can suddenly vary considerably between two locations what are not separated by very much geographical distance and would be more of a topographical consequence of the change than anything else. So the same cycle may be there but out of phase. If I attempt to add the two data sets together, the signals might cancel to some extent and suppress the actual manifestation strength of the signal.

  152. I did a similar thing about a year ago (using the 1000-1900 time frame as a callibration period) and pretty much got the same exact results as the Chinese are getting when projecting out to the year 2200.

  153. So, is this study going to be listed in the IPCC report? Or is it going to be “kept out somehow” even if means redefining what is peer-reviewed literature?

  154. I seriously question their error bars. They seem far too close even for 200 years ago, much less 2000.

  155. I digitised (not perfectly) the 40 year moving average temperature ( top chart above ) then messed about fitting sinusiods to it using ‘PAST’ – nothing very strong came out.
    THEN I put the series into Eureqa; it bumbled along for a few minutes fitting away. All of sudden everything was gone , replaced by fits explaining 97% or more of the variation:
    Try this :
    T= 2.1717854 + 0.35482275*cos(0.53979379 – 20.583712*YR)
    for R2 = 0.97

    Or this for R2 ~ 0.999:
    T= 2.1842875 + 0.51722431*sin(2.1544902 + 0.39110953*sin(2.14483 – 20.583714*YR) – 20.583714*YR)

    Maybe I am losing my marbles Tallbloke? …….Nurse!?……Nurse!!??……..

  156. Alcheson says:
    December 8, 2011 at 1:19 pm

    I did a similar thing about a year ago (using the 1000-1900 time frame as a callibration period) and pretty much got the same exact results

    And I suspect so has Keith Briffa and Michael Mann and Phil Jones and the rest of the now-discredited “hockey team”. I am guessing they knew full well in the early 1980’s that we were going to likely see (barring any unusual solar grand minimum) a rather steady rise until about 2000 and knew they had 20 years in which to campaign. Now I will give deference to Briffa because he seemed rather reluctant to be portrayed as a raving AGW fanatic and maybe this is exactly why. That also might be exactly why some saw this alarmism as not being wise in the long run. I note in some of the climategate emails a sense from some people that this could be cyclical and a reluctance to go along with CO2 being any primary activation component in any of this change we are seeing.

    But this might be why the ranting from the purveyors of this now-discredited hypothesis became so shrill and so desperate; because they realized their time window was closing. And that may now be why we hear barely a whimper out of Durban; because now we are sliding down the other side of that slope and they know it and it will only become more difficult to convince people it is warming when more and more records will require more and more “adjustment” in order to show any warming is taking place. We have probably reached or have nearly reached the tipping point where they can no longer adjust things enough to show warming and will have to come up with a different scare to keep the money flowing.

  157. Does this data use thermometer data for the last hundred years, like Mann’s hockey stick, or did tey use tree ring data for the entire plot. If the latter, this study doesn’t suffer from the divergence problem, and may be a more accurate local temperature record.

  158. I forget to include in the earlier post that the 1000-1900 time frame I fitted is from the 1990 IPCC graph (pre Hockey stick)

  159. The evidence in this paper is entirely consistent with the following post that I placed on another forum because it shows exactly the sort of pattern one would expect to see in a single region as the climate zones overhead shift latitudinally to and fro in the process of maintaining overall thermal equilibrium despite variations in forcing factors.

    “Note that the ONLY effect of ALL factors capable of changing climate is to influence the rate of energy flow through the system. At any given moment all those factors are netted out to cause either slight warming or slight cooling.

    The system can only respond to changes in the rate of energy flow through the troposphere in one way, namely the surface air pressure distribution which is intimately connected to the size and/or speed of the water cycle.

    When the surface air pressure distribution changes significantly it does so by altering the relative sizes, intensities and average latitudinal positions of ALL the permanent climate zones.

    If the net forcing effect of ALL variables is towards warming then the surface pressure redistribution acts to speed up the rate of energy flow through the system to maintain equilibrium by shifting everything towards the poles.

    If the net forcing effect of ALL variables is towards cooling then the surface pressure redistribution acts to slow down the rate of energy flow through the system to maintain equilibrium by shifting everything towards the equator.

    Once that is understood the only question to be determined is as to how far human CO2 emissions change the surface air pressure distribution as compared to sun and oceans.

    Given the scale of the surface air pressure redistribution between MWP and LIA it cannot be much.

    One can still debate the relative contribution of all the available variables so that is the next step.”

  160. crosspatch says:
    December 8, 2011 at 12:34 pm
    “And we can point to the temperature response since 2000 to show that the analysis apparently does have some predictive pattern. The tree ring survey does not contain data for those years yet the resulting waveform accurately depicts what we see in actual observations.”

    Sorry, crosspatch, but extrapolating from graphs has never amounted to prediction and never will. It is quite easy to prove in a common sense way. If the actual observations turned out not to be what the “waveform depicts,” what would be falsified? Graphs are neither true nor false. If a graph can be true then what is it true about?

  161. By the way, I love this comment over at CA:

    The rule is: the MWP happened everywhere, so it was a local phenomenon. AGW is instead happening nowhere (in particular), so it’s a global phenomenon. Easy.

  162. Vukcevic the graph I posted was Loehle with the instrumental record added. Notice your graph ends in 1920 or so, so it doesn’t contain the past 90 years rendering comparisons with current temperature impossible.

    I don’t see any peak in that reconstruction at 1200AD. It peaks at 1000AD

  163. “So the relative strength of the various signals can vary according to region of the planet. If there is movement of weather patterns such as the ITCZ with the 800 year cycle, it might have a profound impact in one area and much less (or opposite) in another.
    So the energy distribution among the various cycles found might be different in different regions (or even hemispheres) of the planet and the cycles could be out of phase between locations.”

    Just so, and the main effect of a faster transmission of energy through the system from equator to space would be ‘excess’ warming at the poles just as we see now but in the Antarctic the effect would be much reduced because warm water cannot get under the ice and the continent is so large that warm winds don’t get to the centre though they do affect the West Antarctic Peninsula.

    The global thermostat is actually a planetwide extension of Willis Eschenbach’s idea. It isn’t ‘just’ more convection in the tropics. It is actually the ability of the permanent climate zones covering the entire planet to shift latitudinally so as to provide the necessary negative response to ANY forcing so as to keep global temperatures within a relatively narrow range.

    This paper is a picture of the process in action above one specific region.

  164. Ian W says:
    December 8, 2011 at 11:47 am

    Good challenge. No doubt you would agree that it needs to be set out in more detail.

  165. crosspatch says:
    December 8, 2011 at 11:47 am

    So, you think tree ring width is a linear function of temperature? Please explain.

  166. I’m suspecting that if you took the SST data and ran it through you are going to see the 60 year cycle as the dominant energy lobe and I would speculate that will be activated by the thermohaline circulation cycle.

  167. I agree that it’s great this paper was published.

    However, my informed rejection of temperature as the initial determinant of ring growth applies equally to both this paper and the Mann-O-Matic. Increasing temps may induce additional precipitation and therefore are somewhat related to growth, but precipitation remains the dominant driver.

  168. So, you think tree ring width is a linear function of temperature? Please explain.

    I do agree with Briffa that in certain locations, temperature is the primary growth constraint. This doesn’t hold in a global sense, only in very local conditions. The tree in my front yard is not a good temperature proxy. A tree near the edge of the boreal tree line might be. A tree that grows in an area that gets no rain during its growing season (so there is no variation in precipitation in June/July) in a mountain area near the high altitude tree line might also be.

    In places where temperature is the overall constraint on annual growth, it may be a good proxy. But we can not say that a tree in such conditions NOW was always in such conditions. As I also said, things change. That same tree might have been under a persistent storm track 400 years ago. Giant Sequoia might be a better rainfall than temperature proxy, for example. A tree that has lived a very long time might alternate from being a rainfall proxy for some period of the record to being a temperature proxy. O18 analysis of the wood in each ring might be a better temperature signal than the width.

    Generally, I don’t like trees being thermometers. If you find one that is, it is more luck than science. Traditionally trees have been used more as precipitation proxies than temperature.

    But MOST importantly, this SAME sort of analysis has been run with actual temperature records and shows the same composite.

    Also, for this case, it probably doesn’t matter if they are temperature or rainfall because the two often go hand in hand. You rarely see a significant multidecadal change in precipitation trend without it also being accompanied by a change in temperature. So bottom line is that overall growth conditions changed in a way that the graph depicts. Running a real temperature series (not a temperature PROXY), in this case CET, shows exactly the same cycles in play.

    This is NOT a result unique to these trees.

  169. Tony Brown did with lot of hard work at the MetOffice archive and reconstructed temperature from 1550-1650:

    I’m always skeptical of “reconstructions”, particularly if relying on 16th century chronicles. Though one might find some interesting data from Chinese observation. I wonder to what extent some old chroniclers recorded weather observations going back thousands of years.

  170. Observer says:
    December 8, 2011 at 4:25 am

    Liu Yu :
    “In northern China, the warmest period occurred from AD401-413, which had an annual mean temperature 0.16 degrees Celsius higher than today’s. Other periods, including 604-609, 864-882 and 965-994 had temperatures higher than in recent decades. Our results are supported by historical documents from the period.”

    There seems to be some very cold NH winters in 407 and 411: http://booty.org.uk/booty.weather/climate/100BC_499AD.htm
    in 604: http://booty.org.uk/booty.weather/climate/500_750.htm and in 608 the Euphrates froze.
    874 and 881: http://booty.org.uk/booty.weather/climate/751_999.htm

  171. Now the chinese have copied the tree ring method too. They take everything they can from the west and just copycat. However, this graph clearly shows they have yet to catch up; since it is no hockey stick they still have to learn how to fudge data ;-)

    /sarc off

  172. would be ‘excess’ warming at the poles just as we see now

    Can you give an example of this excess warming that we see now? I have been having trouble finding any. Southern Ocean sea surface temperatures seemed to have been trending flat from 1982 through 2007 but seem to have recently “stepped down” and appear to be establishing a new trend line about 0.2 degrees lower.

    The Arctic Ocean is interesting in that it did trend upwards from 1997 to about 2005 but now appears to be reversing that trend.

    At the same time, the temperature trend in the Indian Ocean appears to be the only ocean with an increasing trend. It was flat in trend from 1982 to 1996, rose from 1997 to 2002, trended down until 2008 and has had a significant uptrend since then.

    Equatorial Pacific temperatures have been trending generally downward since the early 1980s:

  173. Here is a plot of the simplest (4 parameter) fit, r2~0.97 , av abs residual ~0.02 degress

    A Plot of the actual grabbed 40 year temperature versus the fit:

    The more complex fit mentioned in the previous post seems to be simply a straightening this curve (which brings the average absolute error down to only ~0.002 degrees )
    I am surprised by the complicated behaviour of such a simple equation, -Maybe I have made a terrible mistake.
    Does anyone happen to have a copy of the actual dataset???
    Thanks

  174. crosspatch says:
    December 8, 2011 at 2:18 pm

    “But MOST importantly, this SAME sort of analysis has been run with actual temperature records and shows the same composite.”

    I trust those temperature records just as much as I trust the tree ring proxy records. And I am not talking about simply calibration or quality of thermometers. I am talking about management of thermometer records. The best evidence for management of temperature records is Anthony’s website on siting of weather stations. It proves beyond a shadow of a doubt that management was ridiculous. Our benighted climate scientists will not touch the point because it takes away one of their toys.

    By the way, you clearly agree with me on empirical design and testing.

  175. nomnom says:
    December 8, 2011 at 12:52 pm
    Neither of those estimates match empirical observation, do they. You are entitled to your opinion, but you are not allowed to rewrite known history.

  176. crosspatch,

    Interesting data, thank you.

    As regards the Arctic it was the 1997 to 2005 period I had in mind. I think the warming effect of that warmer water peaked as regards ice melt in 2007 and is now on the turn.

    An interesting issue is that warmth in the Arctic can occur when the globe is warming, from more warm water under the ice AND when it is cooling from more frequent ingress of warm air flows due to more meridional jets.The water effect would be the stronger due to the thermal capacity of water.

    When the globe is warming the poles get cut off by faster and closer circulation of winds around them (more zonal jets) so the Arctic is warmed primarily by water at such times.

  177. Anthony and Observer, thank you.

    This goes into the evidence necessary for making decisions. I expect to see more records in the upcoming decade. It would be a mistake to give this data set and the resultant model too much or too little weight.

    It will be interesting to see how close the observed tree ring widths are to the modeled tree ring widths in the future.

  178. “Southern Ocean sea surface temperatures seemed to have been trending flat from 1982 through 2007 but seem to have recently “stepped down” and appear to be establishing a new trend line about 0.2 degrees lower.”

    As per Bob Tisdales work the SSTs are a fine balance between El Nino discharge mode and La Nina recharge mode. We had a run of strong El Ninos in the late 20th century after a period of negative PDO recharge so one would expect to see a decline during the period as the discharge progressed.

    However the odd feature of the late 20th century was that even while El Ninos were strong the ocean heat content still seems to have risen even if the surface waters did cool off a bit.

    Likewise now that the El Ninos have faded a bit with the negative PDO the recharge process seems rather puny.

    To deal with those aspects I have introduced a cloudiness factor which if correct would have allowed more solar energy into the oceans when those strong El Ninos occurred for a net rise in ocean heat content despite the ongoing discharge process.

    Now the cloudiness factor would be restricting the recharge process despite the negative PDO.

    I need a few years of ongoing observations to validate that idea.

  179. OK, forget about proxy reconstructions. This data shows the growth of these trees is rapid in the last few hundred years. It also shows they have grown at this rate or faster in the past. That by itself casts some serious doubt over the current warming trend being “unprecedented”.
    That is assuming the data is not corrupted. That’s a pretty big nail in the AGW coffin all by itself.

  180. Tangentially related: how warmers are trying to get rid of the 13th century cold period and create a Mongolo-genic cold period. Some traditional climatologists have considered this drop in temps as a precursor of the Little Ice Age.

    I remember being taught in school that the Mongol invasions of the 13th century were likely kicked off by Arctic cold driving across the Steppes from Siberia. Drought conditions may have ensued, robbing the nomads of their fertile grasslands as cold winds scoured the taiga and Gobi to the south. Such a dip in mid-13th century temperature are shown in the above chart from Jo Nova, as well as other proxies of the area. See:

    http://pages.science-skeptical.de/MWP/Zhang-2003.html

    http://pages.science-skeptical.de/MWP/Paulsen-2003.html

    Moreover, recent press coverage has spotlighted the return of devastating arctic temperatures to Mongolia in the last few years; it has wiped out livestock, and caused a massive migration of mongols into the cities. Looking at contemporary pictures of Mongolia in wintertime, it isn’t that hard to imagine comparable cold driving Ghengis and his Horde off the Steppes during the 13th Century.

    http://news.xinhuanet.com/english2010/world/2010-01/30/c_13157184.htm

    But if you Google “Mongol Migrations” and “Climate”, the Mongol hordes weren’t escaping the cold. They apparently were causing it.

    These days (based on a single post-grad *study published in the journal, Holocene) hundreds of articles (page after page in search engine Google) reveal how the Mongols themselves caused a global reduction of CO2 in their bloody conquest. By killing off so many people, forests were allowed to regenerate across Asia, the Middle East and Europe. The renewed greenery gobbled up the CO2. The lesson is clear for modern man: wipe out civilization in order to reduce the CO2 in the atmosphere and restore the killing cold of the Mongolian Steppes.

    http://news.discovery.com/earth/mongols-vikings-and-romans-connected-to-climate.html

    Weather change causing human migration? Such a fantasy!

    Humans causing CO2 (and possibly the weather) to change? Now, that’s the way to do history nowadays!

    * J. Pongratz, K. Caldeira, C.H. Reick, and M. Claussen, 2011: Coupled climate-carbon simulations indicate minor global effects of wars and epidemics on atmospheric CO2 between AD 800 and 1850, The Holocene, doi: 10.1177/0959683610386981.
    Press coverage: Interview on BBC World Service.

  181. The fundamental problem is that we do not have any good high-resolution temperature proxies in temperate regions that pre-date the thermometer. Every single one that I can think of would be “disturbed” by precipitation changes, flooding, etc. There are some fairly low resolution proxies but these aren’t good enough to “catch” things in the recent (Holocene) past that vary on annual or even decadal time scales. I would be interested in any speleothem research done in someplace like Mammoth Cave. I can find such work for the tropics in South America. The South American work seems to be another validating point showing the ITCZ greatly influencing rainfall and its general migration South in response to the decline of solar insolation decline in the Northern Hemisphere starting about 9000 years ago. What is most interesting to me is the sudden appearance of “noise” which they wonder is an ENSO signal that begins to appear only 4000 years ago. See figure 6 on the 126th page of this PDF thesis (page 104 of the document)

    http://dare.ubvu.vu.nl/bitstream/1871/13246/5/8837.pdf

    And I would also be interested in this paper if I can find it for free someplace:

    http://geology.gsapubs.org/content/38/5/455.abstract

    It looks like we can find some rather good data if it is located in exotic places to which someone might want to travel. We can’t seem to find anyone willing to travel to Kentucky to do it, though.

  182. However the odd feature of the late 20th century was that even while El Ninos were strong the ocean heat content still seems to have risen even if the surface waters did cool off a bit.

    Likewise now that the El Ninos have faded a bit with the negative PDO the recharge process seems rather puny.

    El Nino is a little counter-intuitive. El Nino is basically the ocean dumping heat into the atmosphere and La Nina is the ocean gaining heat. During La Nina you have strong trades and reduced clouds. While you do have surface cooling at the very, very surface due to increased winds, you also have more sunlight so just below that surface you have a net gain of energy during La Nina relative to El Nino. This water gets pushed into the Western Pacific and Indian Ocean. You will see an increase in ocean temperatures off of Japan when you see a reduction in temperatures off of California and then the reverse will be true when PDO changes phase.

    So La Nina results in a reduction surface temperature in the equatorial Pacific but a net gain in heat energy that then gets distributed around. At least that’s how I understand it, albeit very simplified, from reading Tisdale.

  183. Hmmm, I think my fits must be some kind of artifact of the digitisation; If the Eureqa functions are fed with equally spaced years then only a slightly distorted sine wave comes out . Getdata digitiser seems to digitise continuous lines by taking points that are equaly spaced along the distance of the line i.e not equally spaced in time, So it is probably some very wierd form of aliasing.
    Oh well :-)

  184. Theo Goodwin says:
    December 8, 2011 at 2:59 pm

    In an overall sense, I agree with you. CET is a different animal, though, from something like GISS or HadCRUT. This would have been done, I believe, with the raw CET observations. But I am confident that you will get a similar result from stations at a similar latitude in the same hemisphere. As you migrate away from that latitude the strength of some of those cycles may change and the same as you migrate inland from the sea. I would expect Amarillo, for example, to maybe have less of a teleconnection to the NAO and probably more of one to ENSO than CET does.

    A place like Venezuela would show a very strong signal from variations in the position of the ITCZ while Kansas City would show none.

  185. I see that “nomnom” is the nom du jour of the troll assigned to WUWT by The Team…

    Well, OK, I’ll take a small bite out of the Troll Bait:

    Dear NomNom, the globe does not ‘all go together as it goes’. It has time lags in some areas relative to others. It has oscillations that move in counterpoint. It has feedback loops and natural oscillations and teleconnections. Sometimes moving in opposite directions in different parts of the world.

    Look up the AMO and the PDO and the ENSO. Learn about the way that the southern hemisphere often moves in opposition to the northern hemisphere in some time scales.

    This is what is called “complex” behaviour. (As opposed to “the hobgoblin of small minds”, or a foolish consistency…)

    So, you see, you can have a process that has onset in one place (like Europe) and takes a hundred years, or maybe even 200, to spread around the globe to other places.

    I’ve frequently complained about the “over averaging” done to temperature data. (And been assaulted by the foolish for that statement). The simple fact is that averaging is done to HIDE things. (Often with very good results). I use a 25 day simple moving average to HIDE daily price movements in stock as they are largely news event driven. I want to see the longer term forces at work, not the daily noise. Hiding can be good… But sometimes hiding is bad.

    In the case of global climate and weather cycles, averaging over the whole globe is bad. We know it is bad as we know there are longer cycle changes that affect different parts of the globe in opposition. (Yes, I really do want you to learn what the ENSO is and how the N vs S hemispheres have things that move in opposition). So averaging them together can HIDE what we want to FIND. Like the decline… (but I digress…)

    Oh, and on the topic of cycles, I see that someone posted a link to Timo. He has a GREAT page on all the possible solar cycles. (I’m figuring folks can find it on their own…). There is also this interesting page that finds a lunar position driven cycle:

    http://www.pnas.org/content/97/8/3814.full

    Or, rather, many cycles. Plenty of real physical things that can drive the weather (even the long term weather cycles that warmers like to call climate, even though it isn’t…) on changes of durations up to 1800 and 5000 years.

    Unfortunately for the warmers, things are kind of cold right now (and have been getting colder since we hit a peak in 1998 … you know last MILLENNIUM ;-)

    On the question of “did they know”: I suspect they did. Not only the Hansen synch change with the cold / warm 60 year cycle, but the way the “narrative” changes in sync with expectations just BEFORE those events ought to happen…

    So we had “Global Warming” up to the late ’90s, then it morphed into “climate CHANGE” just as we hit the peak. Then just about the time the sun was about to go very sleepy, causing a UV plunge, shortening of the atmospheric height, and more violent winds – about like they were in the last similar event… Suddenly then we get “climate chaos” and stories of more wind related damage (hurricanes, tornadoes, ‘extreme events’) just a few years BEFORE they ought to happen from the shorter air column giving higher wind speeds (though of colder air…)

    There is only so much “perfect accident” you can see before you start wondering where Remo is right now… (Google Remo Williams… 1985 or so, has Kate Mulgrew in it too)

    So Occam’s Razor says the most simple explanation that accounts for all the known facts is that folks were seduced by power, believed in their own ability to pull off the dodge, and thought they were doing ‘the right thing’… but were wrong… THEN the schedule did not go as planed… Gang Agley as it were. They forgot that folks, especially the apathetic “rubes”, could take a Very Long Time to get on the band wagon. We had things building to a fever pitch in about 1985 – 1990… and The Folks didn’t quite notice… Took until about 2000 to really get on board. And by then they were behind schedule. Instead of a decade to show how The Solution Had Worked!, the were past the inflection point and into damage control… Time for “Climate Chaos”…

    So now they are doing the last ditch histrionic SCREAM!!!!

    And the rest of us are doing a “What? You overactor!” (in a Jim Carry kind of way:
    http://youtu.be/eju7zSmHklA )

    At any rate, we will now see, IMHO, a long drawn out process as folks both try to continue the effort ( This time for sure!) while trying to find ways to “distance themselves” from the inevitable fiasco as things go obviously cold. Very Cold…

    BTW, for folks wondering where I’d gone:

    I got a job on the other side of the continent. Then came home, Then had two wisdom teeth removed… (Yes, nearly 60 and still teething…. it’s those slow genes from the Neanderthal side, I’m sure ;-) but, to quote Independence Day: I’m BaaAAAAK!!!

    Yeah, back short a couple of teeth… but hey, I can always gum ‘em to death ;-)

    Per the posting: I think the Chinese have always done careful detailed (and sometimes over complicated) work. Looks to me like they are still doing careful work…

    Oh, and per things that make trees grow: In the Pacific NorthWest they found that much of the nitrogen and phosphorus that got to the pine forest came from Salmon caught by bears, then carted off into the forest where bears do what they do in the forest… (“Does a bear Shxx … in the forest?”) So to the drivers of Tree Rings one must add salmon run size and Bear Poo….

    I’m willing to assume that bear poo is not a major factor in Tibet Junipers… but you have to watch out for it. Especially in places with a lot of salmon… Like maybe Yamal… (Mann, have you looked at the POO climate driver? Maybe that’s the cause of the decline… not enough bear pooing in the forest… I’m sure POO is involved some way or another in the results…)

  186. Theo Goodwin says:
    December 8, 2011 at 1:41 pm
    …” extrapolating from graphs has never amounted to prediction and never will”.
    This is not entirely true. If a process goes in cycles and you have enough data to cover multiple cycles, you can with a high degree of probability predict what will happen next even you you don’t understand what causes the cycles. You don’t always have to know WHY before you can make a prediction that is likely to be correct. For example, I don’t know why radioactive elements decay, but I can say with a high probability of success that HALF of them will undergo radioactive decay after X amount of time. Using an example of earth climate,. ancient geologic and ICE core data reveal cyclic variations that indicate there are cyclic patterns that of very warm periods and ice ages. Even without knowing about Milankovich cycles, it would still be highly likely that the earth is soon to be entering another ice age(geologically speaking). This prediction can be made because there are cyclic patterns in the data…. you don’t need to know WHY those cycles are there…. you just need to know they are there.

  187. JJThoms says:
    Wow… Just Wow!!

    I looked up ‘Irony’ on Wikipedia, and this is what it told me:
    “Irony (from the Ancient Greek εἰρωνεία eirōneía, meaning dissimulation or feigned ignorance)[1] is a rhetorical device, literary technique, or situation in which there is a sharp incongruity or discordance that goes beyond the simple and evident intention of words or actions.”

    Just so you know, for future reference etc

  188. Alcheson says:
    December 8, 2011 at 4:17 pm

    To predict an event is show that it is an instance of a well confirmed hypothesis. The prediction is made by identifying some factual statements describing the present situation, such as the date, time, and location, substituting those factual statements (constants) into some universally quantified general statement, and deducing a future event from the combination of the hypothesis and the initial conditions. (If the deduced event description proves to be false, one or more of the hypotheses used to deduce it is likely false. I just told you how falsification works with hypotheses which have cognitive content. Tell me how it works with a line on a graph which has no cognitive content.)

    For example, you can use the date and time where you are as the initial conditions, and plug them into Newton’s formulation of Kepler’s Laws to deduce the next date and time that you can see Venus in full phase.

    The well confirmed hypotheses (called Laws when they are sufficiently central to our science) describe the natural regularities that make up the solar system taught to all grammar schoolers. The purpose of science is to discover or create the laws that describe all the interesting physical processes in the universe.

    Notice that Newton’s Laws do not reduce gravity to a mechanism. Neither do Einstein’s Laws. However, they do describe all the natural regularities regarding the behavior of objects in a gravitational field that we know at this time.

    The event predicted is explained by the hypotheses which describe the behavior of the solar system. If someone asks “Why is Venus in full phase now?” you can explain to them Kepler’s Laws and show them on a chart the relative positions of Earth, Venus, and the Sun. That is scientific explanation. Explain to me how you can point to a line on a graph as an explanation of a particular event.

    In the case of radioactive decay, the hypotheses are just like Kepler’s Laws except that they are statistical laws. But statistical laws are just as deterministic as non-statistical laws as long as the scientists are using objective statistics. The statistical laws of radioactive decay are objective in the sense that all the events that can be predicted from the laws are events whose conditions are fully specified. In other words, the events described always satisfy the same set of conditions; that is, there is no comparison of apples and oranges. It does not matter whether the decaying item rests on top of Mt. Ranier or at the bottom of Death Valley.

    Another interesting example is Population genetics which uses statistical laws. The objectivity of their laws is maintained by the fact that the statistical hypotheses are referenced to particular populations which actually exist and are available for study; hence, their name.

    In climate science, we rarely know that a tree ring width reading from a particular tree can be compared to another such reading from another tree. That is because climate scientists, so-called, have not done the empirical work to specify the conditions in the tree and in the environment that cause changes in growth patterns. We cannot compare a tree at the top of Mt. Ranier with another of the same variety and age at the bottom of Death Valley. For that matter, we cannot compare a tree in a dense forest to a tree resting on an otherwise bare knoll though they might be separated by a hundred meters. Climate scientists must do the experimental work to specify conditions causing changes in tree growth so that they are not comparing apples to oranges. They can do this work in labs monitored by graduate students. If they were serious they would have done it long ago. This work would produce the regularities in the trees and in the environment that govern changes in tree growth. They do not have to cover all environments in which a specific kind of tree grows but only those environments that are useful for temperature measurement.

  189. It would be nice if there was a bit of recognition of simple sampling criteria rules. Looking at Figure 2 for example, Nyquist theory dictates that to properly observe/capture a specific frequency, one needs to record at a rate of at least double that frequency, and that’s assuming that the sampling is not out of phase in any way (imagine measuring daily temperature fluctuations by measuring twice a day. The waveform looks completely different if you measure at noon and midnight than if you measure at 6 PM and 6 AM). Furthermore, most experts would say that you shouldn’t assign any value or statistical merit until you have a sampling frequency of at least 6 to 10 times greater than the frequency being observed. If you don’t observe these parameters, you run the risk of aliasing your data, which will show up in a noise power spectra as incorrect frequencies amplitudes and, if memory serves, incorrect frequencies, too, particularly in more complex spectra where multiple discrete frequencies contribute.

    Given that tree rings give you a 1 year frequency, they really should be putting a huge caveat with everything to the right of 0.166 (1/6) or even 0.1 (1/10).

    On the flip side, the frequencies at 1324 A^-1 and 800 A^-1 should be considered dubious as well because only two full cycles of the 1324 frequency were experienced and 3 cycles for 800.

    I do think a document like this is a very good step in the right direction (in contrast to the material put out by Mann, etc.), but the measurement science still has a very long way to go before the data is “tight” enough to merit the claims that many want to make about AGW. I suspect it will never get there w/o an enormous involvement from individuals expert in the measurement sciences.

    I’d also say that I think a natural data set is infinitely more complex and less prone to high precision than a simple physical science calibration (perhaps calibration of a thermocouple), so the scientists are dealing with a very difficult hand. However, they should acknowledge that and temper their opinions accordingly.

    JMHO,

    HF

  190. NotTheAussiePhilM says:
    December 8, 2011 at 5:19 pm

    I have to assume that people who complain about it being tree rings haven’t read through the comments. The same pattern emerges when the same analysis is done on thermometer readings (not in Russia). So I would say that the method of analysis seems to be robust in that the output matches thermometer data and also matches other known signals such as NAO.

  191. E.M.Smith says:
    December 8, 2011 at 4:05 pm

    “So, you see, you can have a process that has onset in one place (like Europe) and takes a hundred years, or maybe even 200, to spread around the globe to other places.”

    Spot on. (It is called Empiricism – science, that is.)

    Thanks for doing this spade work. Nomnom and his climate propaganda circle are working to wear us down. Their time is running short.

  192. crosspatch says:
    December 8, 2011 at 4:02 pm

    Well, crosspatch, (insert broad smile here) we have to do the empirical work if we are to know.

    Your good instincts will drive you to give up the hypothesis that known proxy data in climate science, so-called, is objective.

  193. What is really most interesting is that you will see about a 0.5C drop in temps during the Maunder minimum with lesser drops in the preceding minima. If we are at the same time as these cycles are due to naturally drop, also entering into a solar minimum (assuming frequency of solar minima are not cyclical and already included as one of the activation mechanism of the cycles shown) then we might be in for an even more substantial decline that this data would predict. We could be looking at a temperature regime in the CET like that not seen since the late 1800’s.

  194. So either

    (a) Tree-ring analysis does not give a good indication of past temperatures.

    or

    (b) Tree-ring analysis does give a good indication of past temperatures.

    If a, then the hockey-stick claims are unfounded.

    If b, then the hockey-stick claims are seriously challenged.

    Not good for the hockey-stick either way.

  195. Well, crosspatch, (insert broad smile here) we have to do the empirical work if we are to know.

    Well, I have access to data in many cases but I don’t have the tools. I might possibly be able to obtain the tools, though, if they are open source. Then there would be a bit of a learning curve associated but I am willing to take on the project. I have access to a reasonable powered Linux computer and some storage capacity.

    I would also like to do such analysis on precipitation records as they likely go farther back in time with substantial accuracy and we also likely have reasonable proxies along with very early calibration period overlaps (the ruler was invented long before the thermometer).

  196. Remember, these are CLIMATE SCIENTISTS, so you can’t question them. I hope Alarmist crowd remembers that.

  197. Kasuha says: December 7, 2011 at 10:51 pm
    Fourier analysis on time series may be a lot of fun but until physical background of identified cycles is demonstrated it’s not more than just playing with numbers with zero predictive potential.

    I think he’s right. The predictive ability has to be taken with a lot of salt. The importance of the Fourier analysis may be in what it points to. Is there an underlying mechanism that is predictable? That’s the interesting question.

  198. Steve O says:
    December 8, 2011 at 7:37 pm

    We can question the now-discredited climate scientists, though. Along with their now-discredited hockey stick and the now-discredited AGW hypothesis.

  199. provides examples of an approximate 60-year cycle based on fisheries.

    It has been known for a while that the anchovies and sardines trade places between Japan and California about every 30 years.

  200. higley7 says:
    December 8, 2011 at 6:31 am

    In the Conclusion: “However, there are still uncertainties in our understanding of climate change, and the concentration of CO2 affects the climate.”

    Too bad they felt that they had to mention a trace gas that has every indication of cooling climate rather than warming, if it has any detectable effect at all.

    But higley, may I point out that simply stating “the concentration of CO2 affects the climate” doesn’t say in which direction they say it affects it–it could make the climate warmer, it could make the climate colder, or not much at all; they didn’t specify which. And we all know the climate is continually changing. (Surprising that Chinese scientists leave their study open-ended for an additional sequel or two, just like Hollywood, but then, they’re in it for the duration.)

  201. Theo Goodwin says:
    December 8, 2011 at 5:25 pm
    “To predict an event is show that it is an instance of a well confirmed hypothesis. ”
    “Explain to me how you can point to a line on a graph as an explanation of a particular event.”

    Very well, since it is known that many things in nature tend to be cyclic (seasons, day/night, etc), I hypothesize that earth’s temperatures tends to go in cycles. I now examine all the long term data we have for the earth’s history. We find when the data is plotted into a graph that there indeed appears to be a very cyclic pattern arising in the data. My hypothesis has now been confirmed, thus I can make a prediction. The earth is due to enter another ice age very soon (geologically speaking). I do NOT need to explain what causes the cycles before a prediction can be be made.

    Your second point in quotes above is a strawman. You presume that it is just a random collection of points on a graph that one is trying to make a prediction from. I would agree that you cannot make a prediction based on a set of randomly generated numbers. However, the graph were are making a prediction from is NOT a random collection of data points, it is an estimate of earth temperature versus time. Based on the very cyclic pattern displayed in the data, predictions about future temperatures can be made. That is not to say that if something occurs in the future that did not occur in the data collected to date, that your prediction will be right. However, if nothing new happens in the future that hadn’t already happened in the known past, then the prediction is likely to correct.

  202. Theo Goodwin also says:
    December 8, 2011 at 5:25 pmIf someone asks “Why is Venus in full phase now?” you can explain to them Kepler’s Laws and show them on a chart the relative positions of Earth, Venus, and the Sun.

    Another strawman. If someone asks “When will the next full phase of Venus occur?” You do not need to know any of Kepler’s Laws in order to make that prediction. In fact, Kepler’s laws were developed AFTER they were able to make predictions about the phase. It is because of the periodic and predictable nature of the planets movements that Kepler’s Laws came about!

  203. One thing that comes to my mind in all of this is that we are seeing first hand part of the problem that comes from specialization in science and not enough generalization. Given a signal like the one from the tree rings the very first thing that would occur to an electrical engineer is to run a spectrum analysis on it, see if there were any dominant cyclical components and then attempt to find out what those are. Same with a mechanical engineer who might (as one poster noted earlier) work on things having to do with vibration. I worked in both. My background was in flight qualified electronic hardware and before that in certain signals analysis work. In order to get qualification for gear to be sold to the Air Force, it has to meet certain vibration requirements. Same goes for the Navy for stuff that goes on submarines (Navy goes a lot more for “shock” testing for obvious reasons).

    That folks in the climate sciences didn’t run this stuff through a spectrum analysis isn’t really their fault. It is the fault of being too specialized. Having stuff like this more open allows people with backgrounds in many different disciplines to look at things and possibly spot something that to them is rather obvious but never occurred to someone else without a background that requires doing that sort of analysis all the time.

    I sincerely believe there really is something to this and I also believe that if we get more cross-discipline eyeballs on problems, we might solve a lot of problems a lot sooner.

  204. RockyRoad says:
    December 8, 2011 at 9:29 pm

    That was the obligatory “hockey mask” statement. They had to pay tribute to Jones et al. in order that someone doesn’t try to revoke their doctorate or “discredit” the journal in which it was published. The nod to AGW is now obligatory in order to keep your job.

  205. Regarding Loehle 2007 – the original paper had errors. He thought he had enough data to run a temp series to 1980, but later discovered that was not so. When he corrected the paper in 2008, the series ran to 1935. He made some comments in the correction regarding late 20th century temperatures.

    While instrumental data are not strictly comparable, the rise in 29 year-smoothed global data from NASA GISS (http://data.giss.nasa.gov/gistemp) 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.

    http://www.terrabruciata.com/climate-history.pdf

    Putting it plainly, the smoothed value at 1992 is 0.07C cooler than the peak of the MWP.

  206. In climate science, we rarely know that a tree ring width reading from a particular tree can be compared to another such reading from another tree. That is because climate scientists, so-called, have not done the empirical work to specify the conditions in the tree and in the environment that cause changes in growth patterns. We cannot compare a tree at the top of Mt. Ranier with another of the same variety and age at the bottom of Death Valley. For that matter, we cannot compare a tree in a dense forest to a tree resting on an otherwise bare knoll though they might be separated by a hundred meters. Climate scientists must do the experimental work to specify conditions causing changes in tree growth so that they are not comparing apples to oranges. They can do this work in labs monitored by graduate students. If they were serious they would have done it long ago.

    Are you seriously suggesting that paleoclimatologists simply assume that the tree rings around the world uniformly conform to climate, regardless of local conditions?

    I don’t know what you’ve been reading, but I’ve read studies devoted to testing and trying to understand disparities in tree-ring growth with respect to (and independently from) winnowing climate reconstructions. The late 20th century divergence issue is the most well-known example (but the issue is not well understood). There are many papers from at least 1995 dedicated to that one sub-topic.

    Time and again skeptics assume that no work has been done on x, y or z. They should research before commenting.

  207. crosspatch says:
    December 8, 2011 at 5:30 pm

    I have to assume that people who complain about it being tree rings haven’t read through the comments.

    Is this the same Crosspatch who says:

    Generally, I don’t like trees being thermometers. If you find one that is, it is more luck than science. Traditionally trees have been used more as precipitation proxies than temperature.

  208. NotTheAussiePhilM says:
    December 9, 2011 at 1:23 am

    What I was meaning to point out was that the SAME analysis was done on THERMOMETER readings (not tree rings) and the result was the same. See my comment at

    crosspatch says:
    December 7, 2011 at 10:58 pm

    CET is a thermometer data set, not a tree ring set. Same result.

  209. That folks in the climate sciences didn’t run this stuff through a spectrum analysis isn’t really their fault

    What makes you think they have not? Have you researched to check that assumption?

    One hit on the first page in a google scholar search has Jones and Briffa as co-authors on this..

    Quantitative estimates of 1480 years of summer temperatures in northern Fennoscandia have previously been derived from continuous treering records from northern Sweden. Here we show the results of spectral analyses of these data.

    Search terms were ‘medieval climate spectrum analysis’.

    Slight changes in the search terms brought up spectrum analysis by Mann, Esper, Moberg and others for millennial reconstructions.

    It’s amazing the confidence with which skeptics assume scientists have not thought of x, y or z possibility or method, and how easy it is to discover that these assumptions are incorrect 99.9% of the time.

  210. barry says:

    “It’s amazing the confidence with which skeptics assume…”

    After barry preposterously wrote:

    “Putting it plainly, the smoothed value at 1992 is 0.07C cooler than the peak of the MWP.”

    barry assumes that he knows global temperatures almost a thousand years ago to 0.07°C. I wonder what barry’s qualifications are? Or maybe he has the new Mann-O-Matic Climate Calibration Meter that can read tree ring temperatures to 0.07°C back to the Cretaceous.☺

    But I’m glad barry has come around to my view that the MWP was as warm or [more likely] warmer than now. And since CO2 was very low during the MWP, Occam’s Razor says that it isn’t causing the current warming. Although it may have something to do with the fevered imaginations of the warmist cult.

  211. eyesonu says:
    December 8, 2011 at 1:41 am

    …..What is interesting in all of this (and now we get our tin foil hats) is if maybe some of these people knew this was coming. I mean, running paleo climate data through a spectrum analysis would be something one would think would have been done in the 1960′s. I wonder if they knew these cycles were going to peak at about this time and knew it was a great time to become rich and famous.
    >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>.

    It was known.

    Sometime back I did a time line and all the CAGW propaganda was done after a bunch of scientific discovers were made.

    The continued emphasis on over population and the movement of Capital to Africa, India, Latin America and China, as well as the CIA writing a report entitled Global Governance 2025 at a Critical Juncture, are all consistent with a belief among the World’s Movers and Shakers that a descent into another Ice Age is on the horizon. This belief is based on initial papers by Milankovitch (1938) and Geissberg (1939 & 1971), Kukla & Mathews alerting President Nixon in 1972 and the validation of the Milankovitch Cycle by Hays, Imbrie & Shackelton in 1976

    The typical propaganda we are seeing:

    Earth population ‘exceeds limits’
    There are already too many people living on Planet Earth, according to one of most influential science advisors in the US government.

    Nina Fedoroff told the BBC One Planet programme that humans had exceeded the Earth’s “limits of sustainability”. http://news.bbc.co.uk/2/hi/7974995.stm

    POLITICAL TIMELINE
    The Committee for Economic Development (CED) was founded in 1942 by the Bankers and Corporate CEOs of the USA.

    The group went international:
    The Bretton Woods Articles of Agreement established the World Bank and IMF in 1944

    The founding of the Bilderberg in 1954

    1970 “Who controls the food supply controls the people; who controls the energy can control whole continents; who controls money can control the world” – Henry Kissinger.

    In 1972 UN First Earth Summit chaired by Maurice Strong “Environmentalism” and “Global Warming” becomes a politicized

    Funding for Climate Research Unit (CRU) at the University of East Anglia
    “The Climatic Research Unit (CRU) was established in the School of Environmental Sciences (ENV) at the University of East Anglia (UEA) in Norwich in 1972.”
    British Petroleum (Oil, LNG)
    Central Electricity Generating Board
    Eastern Electricity
    KFA Germany (Nuclear)
    Irish Electricity Supply Board (LNG, Nuclear)
    National Power
    Nuclear Installations Inspectorate (Nuclear)
    Shell (Oil, LNG)
    Sultanate of Oman (LNG)
    UK Nirex Ltd. (Nuclear)
    Source: http://www.cru.uea.ac.uk/cru/about/history/

    White House Office of Science and Technology Director John P. Holdren along with “Paul and Anne H. Ehrlich in the “recommendations” concluding their 1973 book Human Ecology: Problems and Solutions.
    De-development means bringing our economic system (especially patterns of consumption) into line with the realities of ecology and the global resource situation,”
    http://www.liveleak.com/view?i=e41_1284655982&comments=1

    The CIA document dated 1974 predicting an Ice Age. http://omniclimate.wordpress.com/2009/12/03/world-exclusive-cia-1974-document-reveals-emptiness-of-agw-scares-closes-debate-on-global-cooling-consensus-and-more/

    SCIENCE TIMELINE

    Gleissberg (1939 & 1971) identified an 88 yr cycle in the weather patterns http://www.agu.org/pubs/crossref/2003/2002JA009390.shtml

    Note In 1972 the world was in a cool phase and did not start the warming for a couple more years. This made Maurice Strong’s “Catastrophic Antropgenic Global Warming” in 1972 very weird.

    Milankovitch”s “Astronomical Methods for Investigating Earth’s Historical Climate” 1938

    1963 International Geophysical Year – Interest in Milankovitch Cycle

    Hays, Imbrie and Shackleton research on Milankovitch Cycle

    James D. Hays, Columbia University Ph.D. 1964, spent the late ‘60’s developing, in cooperation with Lamont colleagues, a chronostratigraphic framework for deep-sea sediments by connecting the land-dated record of Earth’s magnetic field reversals with marine stratigraphic datums

    By 1970 Hays realized that this marine chronostratigraphy… could form the basis of a global study of Pleistocene climates. He asked John Imbrie to join the Lamont group and the CLIMAP project was born. Hays then asked Nick Shackelton to join CLIMAP and generate an oxygen isotope record of benthic and planktonic microfossils in a Pacific core.

    …allowed Hays, Imbrie and Shackelton to show, through analyses in both the frequency and time domains, that Earth’s orbital variations control the timing of climate change on ice age time scales, proving the theory that Milankovitch contributed so much to developing…. http://www.egu.eu/awards-medals/award/milutin_milankovic.html [Paper published in 1976 but the work was know before that]

    George Kukla and Robert Matthews of Brown University, convened a conference in 1972 “The Present Interglacial: How and When will it End?” (1972)

    “…Kukla and Matthews alerted President Richard Nixon, and as a result the US Administration set up a Panel on the Present Interglacial involving the State Department and other agencies…” http://calderup.wordpress.com/2010/05/14/next-ice-age/

    From the Global Warming types:

    Lesson from the past: present insolation minimum holds potential for glacial inception (2007)

    “Because the intensities of the 397 ka BP and present insolation minima are very similar, we conclude that under natural boundary conditions the present insolation minimum holds the potential to terminate the Holocene interglacial. Our findings support the Ruddiman hypothesis [Ruddiman, W., 2003. The Anthropogenic Greenhouse Era began thousands of years ago. Climate Change 61, 261–293], which proposes that early anthropogenic greenhouse gas emission prevented the inception of a glacial that would otherwise already have started….” http://www.google.com/url?sa=t&source=web&cd=1&ved=0CBIQFjAA&url=http%3A%2F%2Flinkinghub.elsevier.com%2Fretrieve%2Fpii%2FS0277379107002715&ei=Pz1rTP2VDoaBlAf2sNxN&usg=AFQjCNGxtjOlU9XDuU4_P7FNLFL3iIkI-A

  212. barry says: December 8, 2011 at 11:52 pm

    Time and again climate scientists assume that no work has been done on x, y or z. They should research before commenting.

    Mann et al tried to rewrite hundreds of years of historical observations. Maybe he should have studied the history he is still trying to fake.

  213. Two questions comes to my mind:
    1. Where is the sunspot cycle in the spectrum?
    2. What would the spectra of a set of random walks of the same data size look like?

  214. crosspatch, December 8, 2011 at 11:21 pm

    We used Fourier and Spectral Analysis, in the 60’s to isolate inertial sensor “noise” sources. While the “noise” freq., shown in the spectral graphs were “smeared” & not perfect, they did lead to the cause of this “noise”. As a result we had a much better understanding of these sensors, as subsequent missions proved. .

    Fourier methods was just one, of a number of tools, including statistics, probability, math models & computer simulations. Engineers use these tools in the design process, in order to understand the system they are working with.

    I will agree, that many of the climate science people, seem to me anyway, stuck in a statistics “rut”.

  215. It’s amazing the confidence with which skeptics assume scientists have not thought of x, y or z possibility or method, and how easy it is to discover that these assumptions are incorrect 99.9% of the time.

    I actually did speculate in an earlier comment that I suspected they would have as it seems like a natural thing to do. My later statement that they hadn’t done so was due to the lack of any discussion of it in any of the major papers I had read. I did not go back and check *all* of their papers. So if they had actually done the analysis, this discredits them all the more as there would be no good reason for their long flat handle of the now-discredited hockey stick to be published. They would have already known that wasn’t true. I suppose I hear “damning with faint praise”.

    By the way, I happened across a paper today: Late Holocene glacial and periglacial evolution in the upper Orco Valley. (Carlo Giraudi 2008) He shows that glacial advance in the alps was coincident with periods of high precipitation and periods of retreat with low precipitation as evidenced by flooding on the Po river. There were three exceptions to that: Roman Warm Period, Medieval Warm Period and Modern Warm Period (so he certainly finds the MWP in the data, by the way). Generally it was drought that most often causes glacial retreat, not temperatures, except in the three periods noted above. He also says that the current regime is more consistent with that of the Roman Warm Period than with the Medieval Warm Period.

  216. crosspatch: Well, I have access to data in many cases but I don’t have the tools. I might possibly be able to obtain the tools, though, if they are open source. Then there would be a bit of a learning curve associated but I am willing to take on the project. I have access to a reasonable powered Linux computer and some storage capacity.

    It sounds as though you need R. Search out CRAN: http://cran.r-project.org/.

    There are books, among them “The R Book” by Michael J. Crawley. For analysis of time series with examples in R, there is “Time Series Analysis and its Applications: With R Examples by robert H. Shumway and David S. Stoffer.

  217. Dendrogenerativity:
    From a conservative point of view, I would think it would be best to say these scientific studies were measures of ‘dendrogenerativity,’ assuming that ‘generativity’ means ability to grow. That, I think, is all one can really say for sure about studies of tree-ring widths; such-and such tree grew a measured number of millimeters or micrometers in a given year. One could build up plots for the average generativity of various tree species over the years and compare them without having to define exactly what unknown environmental conditions were responsible.

  218. I love the paper’s final paragraph:

    “Obviously, solar activity has greatly affected temperature on the central-eastern Plateau. However, there are still uncertainties in our understanding of climate change, and the concentration of CO2 affects the climate. Further investigations are thus needed.”

    It’s as if the Laboratory Director from Central Planning came in and said, “You guys really need to put this CO2 sentence in somewhere.”

  219. Septic Matthew says:
    December 9, 2011 at 11:47 am

    I started playing with r a very long time ago but it wasn’t as evolved then as it is now (say 1998, 1999) and I set it aside. I can get transform routines in practically every language there is. I am more comfortable with python than r. Here is an example in a neurology application: http://www.sci.utah.edu/~eranders/Erik_Anderson/Publications_files/python_processing.pdf and there is a python interface I can use that can directly call r functions someone else might have. http://www.astro.cornell.edu/staff/loredo/statpy/

  220. Smokey,

    barry assumes that he knows global temperatures almost a thousand years ago to 0.07°C. I wonder what barry’s qualifications are?

    That was Loehle’s value. I merely reported it. I’ve no idea as to the truth of the matter, only what is published by other people

    But I’m glad barry has come around to my view that the MWP was as warm or [more likely] warmer than now.

    Ahhh, So YOU know what the global temps were a thousand years ago. Your qualifications must be impressive. :-)

  221. And since CO2 was very low during the MWP, Occam’s Razor says that it isn’t causing the current warming.

    My favourite bit of skeptic illogic.

    Forest fires occurred well before humans existed, therefore humans cannot cause forest fires.

    Whatever caused it before is causing it again. The same event must always have the same cause.

    But it’s not even the same event, Smokey. The MWP was a few hundred years getting to its peak stage. Modern warming has taken less than a century to get there. In this way the warming seems to be ‘unprecedented’.

    (Nope, I didn’t drill some trees today, I’m just reporting what I’ve read)

  222. barry says: December 9, 2011 at 2:30 pm

    Uhhh, Barry, I gotta suspicion that maybe you never actually studied logic?

  223. It’s as if the Laboratory Director from Central Planning came in and said, “You guys really need to put this CO2 sentence in somewhere.”

    Yeah, the obligatory “hockey mask” that keeps the discredited Mann and Jones off the phone to your academic institution.

  224. barry says:

    “Modern warming has taken less than a century to get there. In this way the warming seems to be ‘unprecedented’.”

    Wrong as always, barry.

  225. RE: barry: (December 9, 2011 at 2:30 pm)
    “‘And since CO2 was very low during the MWP, Occam’s Razor says that it isn’t causing the current warming.’
    “My favourite bit of skeptic illogic. Forest fires occurred well before humans existed, therefore humans cannot cause forest fires.”

    Actually what Occam’s Razor says is that human generated CO2 cannot be presumed to be the only cause of rising temperatures, especially as the calculated (MODTRAN) raw (no feedbacks) sensitivity of increasing the CO2 concentration in the atmosphere is less than one degree C per full doubling.

    David Archibald in his “The Fate of All Carbon” article has projected that burning all the remaining economically recoverable carbon in the world would be just insufficient to reach 560 PPM CO2 in the atmosphere, which would be double the nominal pre-industrial base value.

  226. barry says:
    December 9, 2011 at 2:30 pm

    The MWP was a few hundred years getting to its peak stage. Modern warming has taken less than a century to get there. In this way the warming seems to be ‘unprecedented’….I’m just reporting what I’ve read

    What, no more of your infamous “cites”?

    “But it was just your imagination, barry, once again
    Running away with you….”

    Because the MWP ended, right, around 1300? After which came the LIA which ended around 1750, well before your “modern warming” which you now conveniently limit to the ‘last <100 yrs.' but including the more recent increases in fossil fuel CO2 additions of the last 60-70 yrs. associated with a decrease in temps initially into the 1970’s and without any temp. increase at all in at least the last 13+ yrs.. All despite the valiant efforts of the Indians and Chinese to burn as much fossil fuel as possible, and counting.

    While within the same alleged AGW “modern warming” time period, CO2 = CAGW has not yielded even one correct relevant prediction yet, barry, and your “logic” likewise does not track the general reality above.

    barry, “seems” is the operative term describing what you are dealing with personally and trying to “prove” propagandistically , and it is definitely your favored choice! Just like simply repeating memes here which only please your “perception is reality” imagination.

    And this now by not even trying to give your universally failed cites for your own merely repeated statements. Brilliant tactical move, barry!

  227. Spector,

    Actually what Occam’s Razor says is that human generated CO2 cannot be presumed to be the only cause of rising temperatures

    Agreed, although that conclusion arises from a simple syllogism rather than Occam’s Razor, which doesn’t really apply right here.

    Of course, warming from CO2 is not based on presumptions but empirical testing (despite the strange propensity for some skeptics to claim no empirical testing has been done). Attribution of cause is probably the most important way to distinguish between what happened a thousand years ago and what is happening more recently.

  228. Spector says:
    December 9, 2011 at 6:28 pm

    Actually what Occam’s Razor says is that human generated CO2 cannot be presumed to be the only cause of rising temperatures, especially as the calculated (MODTRAN) raw (no feedbacks) sensitivity of increasing the CO2 concentration in the atmosphere is less than one degree C per full doubling.
    ===========================================================
    I don’t know about MODTRAN, but it’s a fairly straightforward prospect…. if someone can poke holes in this I’d be happy to listen…. I wrote this just a couple of days ago….. http://suyts.wordpress.com/2011/12/06/if-only/ Without factoring the logarithmic relationship and simply assuming a linear one…. I got that we could expect a high/low 1.06/0.93 degree increase when atmospheric CO2 is at 560ppm.

    Of course, that assumes GISS is accurate, the CO2 levels did start at 280ppm and that a temp/CO2 relationship exists at all…..

  229. By the way, apparently Earth’s atmosphere goes through natural carbon maxima about every 500K years. We apparently started one of those about 60kya.

  230. crosspatch says:
    December 9, 2011 at 11:57 pm
    By the way, apparently Earth’s atmosphere goes through natural carbon maxima about every 500K years. We apparently started one of those about 60kya.
    ———-
    Please cite your sources for this claim.

  231. RE: barry: (December 9, 2011 at 7:56 pm)
    “Of course, warming from CO2 is not based on presumptions but empirical testing (despite the strange propensity for some skeptics to claim no empirical testing has been done). Attribution of cause is probably the most important way to distinguish between what happened a thousand years ago and what is happening more recently.”

    It is my understanding that the raw effect of carbon dioxide must be magnified by some assumed interaction with the water vapor absorption bands to obtain the high values required to make it responsible for recent environmental temperature changes, yet the MODTRAN calculated outgoing radiation at 20 km up only shows a narrow CO2 hole in the outgoing radiation; something like a one foot diameter tree in the middle of a twenty foot wide stream. Doubling the CO2 content appears to be equivalent to putting another tree right behind the first one.

    RE: James Sexton: (December 9, 2011 at 8:30 pm)
    “I don’t know about MODTRAN, but it’s a fairly straightforward prospect….”

    MODTRAN is a program developed by the Air Force to predict infra-red radiation levels in the atmosphere with various environmental conditions and altitudes for aircraft systems testing. One version is hosted online as a web utility by the University of Chicago. Here is a link to a comparison plot showing the miniscule difference between radiative forcing of 300 and 600 PPM CO2 observed looking down from 20 km up.

    File:ModtranRadiativeForcingDoubleCO2.png
    “From Wikipedia, the free encyclopedia”
    “Modtran3 v1.3 upward irradiance at 20 km, U.S. Standard Atmosphere”

    As there are no gaps attributed to water-vapor, I assume that convection and perhaps emission spectrum broadening, due to the strong polar electrical attraction of H2O during molecular collisions, may make water vapor a leaky greenhouse gas. The small hole at 1111 kayzers (cycles per cm, cm-¹) is due to ozone.

  232. barry says:
    December 9, 2011 at 7:56 pm

    Of course, warming from CO2 is not based on presumptions but empirical testing (despite the strange propensity for some skeptics to claim no empirical testing has been done).

    You mean “empirically tested” by the “experiments” performed by Climate Science’s Play Station Warming Models? Which can’t even reproduce the empirical past, much less succeed in making even one correct relevant, truly empirical prediction.

    barry, perhaps you should ask yourself why you haven’t learned the difference between your rather boring paranoid fantasyland reveries and reality. Why go through life haunted by your own provenly obsessive perceptions? Or is it simply the fact that the money in it for you to post the usual CAGW propaganda here is just too tempting? Maybe so that you can buy even more computer games?

  233. I think researchers in general gotta be careful about what they claim. I don’t know much about the topic, but even if we’re in a cycle where there are big changes to the temperature, doesn’t mean that what we do don’t have an impact, i.e. those results doesn’t prove that humans have nothing to do with it.

    • What you say is logical. More so if the task is to prove something. But that’s not the task–to prove something. We can falsify thing by the scientific method but we can’t prove anything.

      What is being argued by the proponents of unprecedented global warming is that it the currently observed warming is both unprecedented and in excess of what it was before fossil fuels were much used. The paper being discussed here seems to falsify that hypothesis by showing that periods in the past did enjoy warmth at least equal to that of modern times.

      I use the word “enjoy” in a deliberate fashion because my study of climate history tells me that cold periods were times of less joy than modern times.

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