Predict future climate change!

[Steve: Editorial comment] – This is John A’s post. I do not agree with his editorial flourishes linking this to models. I view the following as illustrating the defects of sole reliance by multiproxy reconstructions on the RE statistic – a statistic for which there are no distribution tables and which is little known or unknown to ordinary statisticians and unstudied outside tree ring circles. This is a battleground issue with respect to Mann and similar studies and it is important to illustrate how it operates; this is useful enough; I don’t view the post as showing more than that.]

Dave Stockwell has shown the future of climate prediction with a great new device that allows you create a new prediction of future climate change which are at least as good as the tree ring proxies were for the past. Arguably this new technique puts expensive climate modelling exercises like to shame.

Here’s a prediction of future climate generated each time the page is refreshed. Note that the RE and r2 statistics are calculated automatically.

The data in blue is the instrumental data (courtesy of the CRU) and the red is the prediction of future temperatures for the next 100 years.

The explanation is here and the source code can be found here

Let Dave Stockwell explain:

The validation is based on the 11 points at the end of the temperature record not used in generating the simulated points. Two statistics were calculated and can be seen on the figure:

  • The R2 correlation is ubiquitously used for quantifying the strength of association of two variables. A critical value of 0.1 would indicate a possible mild correlation, but values closer to one indicate significance.
  • The RE reduction of error statistic is used in dendroclimatology and in the “‹Å“hockey stick’ reconstruction of MBH98, where critical values greater than zero are claimed to indicate significance of the model. RE is claimed to be superior to the R2 statistic in WA06.

Hit reload a few times to get a feel for the average of the statistics. The R2 statistic is usually close to zero indicating the prediction has no statistical skill over the validation period. The RE statistic, however, is always greater than zero, and often greater than 0.5.

MBH98 uses an RE benchmark of zero to indicate significance. The random numbers here give RE statistics greater than the critical value of zero. Therefore, using the RE statistic with a critical value of zero would attribute statistical skill to random numbers. That is, under criteria used in MBH98, random numbers could be regarded as skillful predictors of future temperatures.

This example illustrates (if the code is correct) a situation, similar to MBH98, where the R2 statistic correctly indicates no statistical skill in the predictions, but the RE statistic erroneously indicates statistical skill.

Conclusions hinge on the choice of statistic and where you set the benchmark. MM05 obtain a critical value for RE of greater than 0.5 using random red-noise data in a replication of the procedure used in MBH98. Non-existent statistical skill of the models is one of the main arguments in MM05 against the reconstruction method in MBH98.

So there you have it, statistical skill or not? If the statistical tests can be equalled or bettered using random numbers which have long-term persistence, then the next IPCC review, just like the previous one, will contain just as much information to inform policymakers as a table of random numbers. If this is so, then why are climate journals still publishing studies with just this behavior?


  1. Posted May 3, 2006 at 4:15 AM | Permalink

    Is this the future of science?

    This blog has been both informative and entertaining for me. The later threads contain lots of interesting science discussion which has served to educate me. The participants have even learnt to control the discussion and keep things on track – well done. I hope the trend of diminishing ad hominems continues. (I dream of the day they dissapear alltogether)

    I hope this thread is intended as humour and not farce. We need more humour and less emotion and farce in this science in order to produce better results.

    I have enjoyed playing with the graph – pure entertainment, but it makes me focus on what I should learn.

  2. Jim Erlandson
    Posted May 3, 2006 at 4:30 AM | Permalink

    If Steve M had listened to John A about Adwords, he’d be sittin’ in clover today. Thousands of amateur climatologists from around the world hitting refresh over and over to see new versions of the future … the hits keep coming.

  3. Nils Harder
    Posted May 3, 2006 at 4:47 AM | Permalink

    Why would be expensive? I thought it was one of the most cost-effective way to carry out climate model experiments. For example, this method of distributed computing was for SETI@Home the only way to survive after funds have been cut…

  4. John A
    Posted May 3, 2006 at 5:53 AM | Permalink

    Re: #2

    I keep telling Steve, but he insists that wearing a hair shirt and flagellation are the only proper way to run a climate science blog.

  5. Posted May 3, 2006 at 6:03 AM | Permalink

    although the site is for the purpose of climate audit , climactic changes , in the ground reality , are really amatter of dailyclimactic experience , observed daily in the atmosphere ., and , not simply amatter of statistics. you sholud do well to bring the theme of climactic changes closer to lived and felt experience.

  6. John A
    Posted May 3, 2006 at 6:08 AM | Permalink

    Re #1

    I hope this thread is intended as humour and not farce. We need more humour and less emotion and farce in this science in order to produce better results.

    My personal belief is that any confidence in climate modelling to predict the climate 100 years into the future is absurd. But, using Pascal’s Wager, it won’t stop lots of taxpayers money being spent in the offchance that they’re correct.

    So my answer to your first statement is: both

  7. jae
    Posted May 3, 2006 at 6:42 AM | Permalink

    This is great. Now, nobody has to go out and wound trees anymore.

  8. Posted May 3, 2006 at 8:24 AM | Permalink

    My somewhat complementary comments on this nice script are here:

  9. Ross McKitrick
    Posted May 3, 2006 at 9:00 AM | Permalink

    #1 – Harry, this thread is humourous, but don’t overlook the fact that it also makes a very important point with ramifications for ongoing debates. The combination of a high RE and low r2 signals a spurious statistical result. While we chuckle about Dave’s superb simulator, serious journals are publishing papers by VIP climate scientists who claim that the r2 in this sort of situation is irrelevant and misleading, and the RE should be all that you look at. If this claim is false, certain famous scientific results unravel with it, and a certain famous international science assessment report gets a hole blown through its middle, and — if hypothetically — subsequent famous international scientific assessments were to rely on the VIP arguments to defend a previous famous international scientific assessment then they are all going out on the same limb, against which the saw is now positioned.

  10. jae
    Posted May 3, 2006 at 9:09 AM | Permalink

    The saw is already at least half way through the limb.

  11. Posted May 3, 2006 at 9:54 AM | Permalink

    Re: 9. Bravo Ross – exactly. But what does it take to get their attention regarding these points? Why is the citeing of MM05 studiously avoided in the recent literature if the claims are so important? These are the questions that I am going out on a limb over.

  12. Doug L
    Posted May 3, 2006 at 10:17 AM | Permalink

    I don’t see any humor here, what I see is triumphalism! 🙂

    meep meep!

  13. TCO
    Posted May 3, 2006 at 10:25 AM | Permalink

    I hate this kind of post, John. Serious.

  14. Mark
    Posted May 3, 2006 at 11:33 AM | Permalink

    re #5:

    although the site is for the purpose of climate audit , climactic changes , in the ground reality , are really amatter of dailyclimactic experience , observed daily in the atmosphere ., and , not simply amatter of statistics. you sholud do well to bring the theme of climactic changes closer to lived and felt experience.

    So, you advocate anecdotal evidence as the method by which we should spend billions of taxpayer dollars?

    I think you should first understand that local phenomena regularly change wildly. For example, the Great Dust Bowl of the 1930s in the central US. It’s not a dust bowl now. The Sahara Desert wasn’t always a desert. Greenland used to be green. Global changes, and every one of the analyses using tree-rings attempting to explain them, are a matter of statistics, like it or not. What happens in the US is not necessarily happening in Europe, or anywhere else in the world. What is “lived and felt experience” is only lived and felt from local viewpoints. The only way to explain things on a global scale is to use statistics.


  15. Dave Dardinger
    Posted May 3, 2006 at 11:35 AM | Permalink

    I hate this kind of post, John. Serious.

    Tough toenails, TCO. A lot of us like this kind of post. But, to keep Willis happpy; thank you for your opinion.

  16. Spence_UK
    Posted May 3, 2006 at 12:18 PM | Permalink

    Re #13

    I think punching a lot of random numbers into a simple methodology is a valuable way of getting a good understanding of how different verification and validation statistics operate. A good follow up would be to run a large set (e.g. a few thousand) and plot the pdf.

    How would you go about understanding the behaviour of verification statistics? I certainly hope you would not resort to illustrating pathological examples as seems to be the preference of certain hockey team methods…

  17. Willis Eschenbach
    Posted May 3, 2006 at 12:20 PM | Permalink

    Re 15, Dave, I laughed out loud … made my morning. There was a tsunami warning this morning for Fiji, a I live right by the beach, but it was just cancelled (6:15 AM local time), I was happy, then I read Dave’s post and just cracked up …

    I truly do appreciate people posting, though, whether I agree with them or not. It is this kind of dialogue that moves science forward.

    My best to everyone,


  18. Posted May 3, 2006 at 12:51 PM | Permalink

    Re: 13. Perhaps TCO is offput by the dramatizing of issues. If he is then there are probably others as well. If so I apologize – I was briefly an actor before becoming a full time geek.

  19. John A
    Posted May 3, 2006 at 1:22 PM | Permalink

    I managed to get 0.97 for RE and 0.77 for r2 on one run. Do I write it up for Nature?

  20. Peter Hearnden
    Posted May 3, 2006 at 2:27 PM | Permalink

    Re #14, if Greenland used to be green did Iceland use to be ice? At the same time?

  21. ET SidViscous
    Posted May 3, 2006 at 2:43 PM | Permalink

    Sure why not.

    Of course you do realize Peter that the “green” part was ont the entirity of Greenland, it’s a big place.

    But since Nanortalik is about 375 niles south of Reykjavik and about 650 miles upstream into the Gulf Stream it is possible that the southern tip of Greenland could be slightly warmer than iceland.

    To give you another perspective.

    Your asking, Could the Climate in London be different from Glasgow.

    For Americans Nanortalik is about as far south of Reykjavic as Bermuda is from Boston. You will not that there is a signifigant difference in climate between the two, for much the same reason.

  22. Peter Hearnden
    Posted May 3, 2006 at 3:11 PM | Permalink

    Sure sid, I realise Greenland wasn’t all green, do you realise many parts of it now are green, or, in places, the clean rock left by melting ice?

    Whatever, you’d be better addressing your comments to Mark.

  23. ET SidViscous
    Posted May 3, 2006 at 3:21 PM | Permalink

    I don’t think so. You seem to think anything “Up HTere” is the same. But there are perfectly logical reasons that southern Greenland could have been green, while Iceland was Ice.

    Hence the name.

    What we do know is that it just wasn’t marketingspeak by Erik the Red, because Colonies thrived there until…

    Well until the climate changed. And this was before SUV’s.

    That there is what you call a data point.

  24. Peter Hearnden
    Posted May 3, 2006 at 3:32 PM | Permalink

    Re #23. Sid, please, don’t put words in my mouth. I don’t think anything “Up HTere” is the same. Indeed, Iceland is in the middle of the Atlantic, Greenland on it’s cold NW edge. There is every reason to believe both names are somewhat at odds with reality.

    I draw attention to the two different names. If (IF!) Greenland was ‘green’ then why wasn’t Iceland ‘ice’? Answer, because both names were generalisations, and ‘Greenland’ it clearly wasn’t.

    Oh, and the colonies didn’t exactly thrive. They had few resources bar an easily over used and damaged soil. No iron, no coal, very little wood, difficult trading conditions, but the human capacity for survival. Read Diamond (and others) and loosen some of your prejudices.

  25. ET SidViscous
    Posted May 3, 2006 at 3:48 PM | Permalink

    “”Greenland’ it clearly wasn’t”

    No? You have pictures, video, any documentary evidence.

    The MAJORITY of Greenland is on the Cold North West Edge SOUTHERN greenland is smack dab on the warm gulf Stream.

    “but the human capacity for survival.”


    Then why is a global climate change of a couple or few degrees going to be so devestating? Particualry when it will be warmer which is much more pleasant than a few degrees colder.

  26. Paul
    Posted May 3, 2006 at 3:52 PM | Permalink

    RE #25 –

    hen why is a global climate change of a couple or few degrees going to be so devestating?

    It is? What’s the evidence? I always thought that some GW would make the planet, in general, a better place.

  27. Posted May 3, 2006 at 4:36 PM | Permalink

    Peter H,

    No matter how “green” Greenland was and how much ice was in Iceland in the MWP, it is quite certain that temperatures were higher in Greenlabd during certain periods of the MWP than in the recent decades. From Alexandra Slack:

    Results from Poul Norlund’s excavation at Herjolfsnes’ churchyard, which uncovered plant roots in shrouds covered by a layer of permafrost, indicated that the land, at the time of these Norse burials, had been subject to fluctuating temperatures.

    With other words: in the Norse settlement period where people were buried, plants were growing where now permafrost is…

  28. Posted May 3, 2006 at 4:56 PM | Permalink

    Re #26,

    Ed, sorry, but I think you are mistaken, Southern Greenland is separated from the (warm) Gulf Stream by the very cold East Greenland current, which brings a lot of icebergs from the Arctic and less saline water. The other side of Greenland is only slightly better: the West Greenland current is just the previous one, going round the corner…

    In contrast, West/NW Iceland can profit (to a certain extent) from an extension/side stream of the Gulf Stream, the Irminger current, but that mixes with the East Greenland current and comes back as the cold East Iceland current…

    Thus while there are appreciable differences in average temperature between southern tip and more northern places in Greenland, the average temperatures of Iceland are really better nowadays (and with nowadays ocean currents).

  29. jae
    Posted May 3, 2006 at 5:23 PM | Permalink

    Peter: Read and LEARN!

    There’s a lot more there, too. Too much for me to get serious about your innane, undocumented, biased nonsense.

  30. Lee
    Posted May 3, 2006 at 5:39 PM | Permalink

    Greenland today:

    sarcasm: We know Greenland is ice covered, so this is proof absolute that the ice is melting and it is much warmer now than ever before. BTW, plants (with roots) grow quite well on permafrost.

    I’m sorry, but anyone who declares that it must have been warmer then because it is named ‘Greenland” has pretty much forfeited any expectation of being taken seriously. Arguing that it had to be warmer because a shroud excavated from permafrost has roots in it, ain’t much better.

  31. jae
    Posted May 3, 2006 at 5:51 PM | Permalink

    Lee: beautiful photos.

  32. Lee
    Posted May 3, 2006 at 5:59 PM | Permalink

    a followup: Eirik’s farm at Brattahlid, Eastern Settlement, recently:

    And this, from one of those CO2 Science links, sounds good:

    “During this period, which they describe as occurring between AD 885 and 1235, the outer part of Igaliku Fjord experienced enhanced vertical mixing (which they attribute to increased wind stress) that would have been expected to increase nutrient availability there. A similar conclusion was reached by Roncaglia and Kuijpers (2004), who found evidence of increased bottom-water ventilation between AD 960 and 1285. Consequently, based on these findings, plus evidence of the presence of Melonis barleeanus during the Medieval Warm Period (the distribution of which is mainly controlled by the presence of partly decomposed organic matter), Lassen et al. conclude that surface productivity in the fjord during this interval of unusual relative warmth was “high and thus could have provided a good supply of marine food for the Norse people.”

    Shortly thereafter, however, the cooling that led to the Little Ice Age was accompanied by a gradual re-stratification of the water column, which curtailed nutrient upwelling and reduced the high level of marine productivity that had prevailed throughout the Medieval Warm Period. These linked events, according to Lassen et al., “contributed to the loss of the Norse settlement in Greenland.” Indeed, with deteriorating growing conditions on land and simultaneous reductions in oceanic productivity, the odds were truly stacked against the Nordic colonies, and it was only a matter of time before their fate was sealed.”

    Except they neglected to mention this. I wonder why?

    “Despite excellent conditions of preservation and repeated intensive sieving efforts, fish remains have never been recovered in quantity from Greenlandic sites- a marked contrast to Iceland and the rest of the Scandinavian North Atlantic (Amorosi et al. 1994).”

  33. Lee
    Posted May 3, 2006 at 6:02 PM | Permalink

    jae: they arent mine. Cites to where I got them are easily obtainable from the URLs of those pics.

    And the quote in 32 came from:

    (2002) Archaeologia Islandica 2: 98-136

    Orri Vésteinsson, Thomas H McGovern & Christian Keller

    Enduring Impacts: Social and Environmental Aspects of Viking Age Settlement in Iceland and Greenland

  34. ET SidViscous
    Posted May 3, 2006 at 7:01 PM | Permalink

    Paul. I’m with you, that was a question to Peter, if we could survive adversity in the past, why can’t we survive it now.

  35. ET SidViscous
    Posted May 3, 2006 at 7:20 PM | Permalink


    I’m not sure exactly what a picture of the Tundra says about Ferdinand’s post.

    First as to plants growing in Tundra. The plants do not grow IN permafrost, they grow ON permafrost. The permafrost being below the surface, with a layer of non-permafrost above.

    Secondly to Ferdinand’s quote he mentioned the roots being COVERED in permafrost. That is a particular important distinction.

    It’s not that the ice was below the plant roots, it was that the roots were IN ice(permafrost).

    I’m pretty sure I’m feeling Deja-vu

  36. Paul Linsay
    Posted May 3, 2006 at 7:51 PM | Permalink

    The temperatures in Greenland seem to have risen from 1885 to 1935 and cooled since then as can be seen from Figures 2, 3, & 5. The interior, where the glaciers live, has an average annual temperature of -25 C.

  37. Lee
    Posted May 3, 2006 at 8:28 PM | Permalink

    Sure; growth builds up, soil level rises, permafrost level comes up with it into the previous growth zone. Also, the reference to finding in a shroud; what is that referring to? Unless its some feature I don’t know of (entirely possible; but a quick google didnt turn up anything) that sounds like a burial.

    None of which is all that relevant to my point; “they named it Greenland” and “it was inhabitable” tell us precisely squat about whether the climate was warmer or colder then than it is now.

  38. Dave Dardinger
    Posted May 3, 2006 at 8:43 PM | Permalink

    growth builds up, soil level rises

    Boy, talk about stretches! Just how fast do you think soil is produced anyway? And if it is because of plant growth that pretty well proves that the place was very green.

    Yes a shroud is a sign of burial.

  39. ET SidViscous
    Posted May 3, 2006 at 8:47 PM | Permalink

    From Websters

    Main Entry: 1shroud
    Pronunciation: ‘shraud, esp Southern ‘sraud
    Function: noun
    Etymology: Middle English, garment, from Old English scrud; akin to Old English scrEade shred — more at SHRED
    1 obsolete : SHELTER, PROTECTION
    2 : something that covers, screens, or guards: as a : one of two flanges that give peripheral support to turbine or fan bedding b : a usually fiberglass guard that protects a spacecraft from the heat of launching
    3 : burial garment : WINDING-SHEET, CEREMENT
    4 a : one of the ropes leading usually in pairs from a ship’s mastheads to give lateral support to the masts b : one of the cords that suspend the harness of a parachute from the canopy

  40. Larry Huldén
    Posted May 4, 2006 at 1:37 AM | Permalink

    Additions to # 35 by ET SidViscous.

    The site you give describes the etymology of the word Tundra. It is said that it is related to the Finnish word Tunturi[a] which is described as “treeless plain”. It is possible that the words are related, but in Finnish tunturi means treeless mountain. These are not connected with permafrost. Permafrost occurs in northernmost Finland only in small patchy locations in bogs.

  41. ET SidViscous
    Posted May 4, 2006 at 1:46 AM | Permalink

    No arguement from me, particuarly on Finish with a guy that has a tik mark in his name.

    But the only point with the link was not in the entymology, which anyways was done by Berkley students who I was more surprised that they knew there was a Finland than anything else.

    Their idea of old world Culture is the Colonel of Chicken fame.

  42. Posted May 4, 2006 at 1:53 AM | Permalink

    statistics involves not only the use of instrumentation and technical specifications , but , also , an in-depyth study of the locale and the terrain to be studied. thus , it calls for acombination of skills , and , init’s advanced form , could be avery good and abundant employment generator.

  43. Peter Hearnden
    Posted May 4, 2006 at 2:53 AM | Permalink

    Re #34. Sid, if you think people facing adversity (you seem to be assuming we are, why?)all just sat/sit down and wait to die you know very litte about humans. Otoh, if a place simply wont support as many people as it did that’s also a reality. Outcome? A long, bitter, and eventually unsuccessful battle to survive – the last few being the doomed but most tenacious few.

    Re the last comment in ‘#33. Lee (and I agree with your comments in #30) I’ve read Diamond report similar, it seems the Viking Greenlanders just dind’t eat much fish – which was crazy (or is that ignorant?) given it was there. So, people also do crazy/ignorant things. Tell me something I don’t know…

    Re #29, jae, you certainly appear to be a bit fixated on CO2science, there are other views available you know.

  44. Jean S
    Posted May 4, 2006 at 3:43 AM | Permalink

    re #40: Yes, it is believed that the word “tundra” comes from the Finnish word “tunturi” (which is fjeld in English) although there is basicly no tundra in Finland.

    Permafrost, however, exists in (very northern) Finland not only in palsa bogs and peat hummocks (=”pounu” in Finnish) but also on some fjeld top areas (=”paljakka” in Finnish). For example, it is believed that on top of Saana-fjeld permafrost is up to 100m thick. BTW, NEW permafrost was formed during the winter 1992-1993, see M. Seppàƒ⣬àƒ⢺ New permafrost formed in peat hummocks (pounus), Finnish Lapland, Permafrost and periglacial processes 9, 367-373, 1998. It is still there (see here (in Finnish)).

    You can find more information about nature of North Finland from here. Unfortunately, not all pages are translated, the most relevant page to this discussion (I could not find it in the English section) is here (in Finnish).

  45. Steve McIntyre
    Posted May 4, 2006 at 11:08 AM | Permalink

    I’ve deleted some unpleasant flaming, none of which had any scientific interest. C’mon…

  46. Posted May 4, 2006 at 5:23 PM | Permalink

    Re #30, #32,…

    Lee, as Ed in #35 already responded, the roots are covered by permafrost today, which is only possible if at the time the tundra was formed, the upper layer (including the root system) during summer was defrosted. Permafrost doesn’t melt in summer at all.

    That doesn’t prove the higher temperatures during the MWP completely, as the permafrost cover is settled down later (according to the interesting story by Dale Mackenzie Brown by wind blown glacial sand). Thus depends on how deep the defrosted layer was then and now (for which we have no good MWP data…).

    What you quoted in #32 is not a disprove of warmer temperatures during the MWP. If there was a better ocean mixing (why? because of higher temperatures/ larger temperature gradients?), and a worse during the LIA (again as result of temperature/gradients), what is the state of the mixing today?

    Further, the foto’s of the excavations simply show that the Norse settlements were build on tundra/pastures of that time, I don’t think that they used to build their houses on inland ice…

    For recent times, the main warming was in the 1900-1930 period, followed with a cooler period from 1945-1990 and a warming thereafter. Greenland temperatures now just reach the 1930-1945 temperatures (but not even in summer! See here ). The main initial increase was probably due to solar activity increase, and the other temperature swings probably related to NAO/AMO multidecadal oscillations.

    Thus any extrapolated alarming story about how fast the Greenland ice cap is melting (based on the past 5-10 years), and going to melt/disappear in the near future, should be taken with a grain of salt…

    And have a look at my own Greenland pictures here. I have some pictures of the excavations of the “Eastern settlement” (in fact on the Southern tip) somewhere too, will see if I can get a few on my family web site tomorrow…

  47. ET SidViscous
    Posted May 4, 2006 at 5:38 PM | Permalink

    Who the hell is Ed.

    Once I see as a typo, no sweat, but that’s twice. I assume your refereing to me because my post is 35 and I haven’t seen Snack around here.

  48. Lee
    Posted May 4, 2006 at 7:29 PM | Permalink

    So, roots were buried (maining a hole was dug) and that proves that it wasnt permafrost there because there were roots so stuff must have been growing? Or was it cut roots on the edge of the hole?

    Either way, ti isnt evidence, taken alone like this. Yes soil gets built up over time, and can get built pretty quickly. Permafrost is basically frozen peat; stuff grows on top in summer, freezes and gets pacekd down in winter,and new growth emerges in summer. Annual growth in the peat layers can be substantial (look at hoses pictures I posted); it doesnt take much of a fractin of an inch per year over 400 years to put the surface deep enough to become part of the permafrost layer. Doing an analysis based essentially on how deep the stuff is, and ignoring the process of soil accumulation as if it doesnt ocur, is scientifically groundless.

    and re 46:
    “What you quoted in #32 is not a disprove of warmer temperatures during the MWP. If there was a better ocean mixing (why? because of higher temperatures/ larger temperature gradients?), and a worse during the LIA (again as result of temperature/gradients), what is the state of the mixing today?”
    That quote is from CO2 Science, and the point there was on the credibility of CO2 Science, which was spinning a story about how cooling reduces ocean production and helped end the norse settlements, even though the norse didnt eat fish, which is well known. That is no more evidence for the relative temp, either way, than the name “Greenland” is. Which ws my point.

  49. ET SidViscous
    Posted May 4, 2006 at 7:39 PM | Permalink

    “Permafrost is basically frozen peat”

    No permafrost is frozen soil, in some cases this is peat, but it is not a “basically it is this” thing. Peat is in no way a requirement or in anyway related to permefrost, other than sometimes being part of the permafrost.

  50. Lee
    Posted May 4, 2006 at 7:41 PM | Permalink

    Remember, these are areas where the norse settled and farmed. It is vegetative soil, or they would not have been there. I should have said “this” permafrost; I assumed it would be obvious that is what I meant.

  51. Posted May 4, 2006 at 7:45 PM | Permalink

    A draft of the IPCC (International Panel on Climate Change) Fourth Assessment Report, due for publication in 2007, has been made available for comment by the US government (see Nature, volume 441, pages 6-7 (4 May 2006) for the story).

    Nature states “One critical number in previous reports has been the sensitivity of the climate to increases in greenhouse-gas levels. In 2001, scientists estimated that a doubling of carbon dioxide levels would cause an increase of 1.5–4.5 °C, but acknowledged that this range was little more than a best guess. The draft 2007 WGI report describes how new models and data sets allow the range to be properly quantified. It estimates the effect of doubling carbon dioxide as a rise of 2.0–4.5 °C and, for the first time, suggests a single most likely figure: 3 °C. This estimate is already widely accepted by climate scientists.”

    Details on how to obtain a copy of the draft report for the purposes of making comments are given at ; the deadline for receipt of comments is May 9th 2006.

  52. ET SidViscous
    Posted May 4, 2006 at 8:17 PM | Permalink

    I don’t see where it would be obvious, nor do I see your explanation holding up. While dead plant growth does build up, the insulative factor of the soil does not build up in a one to one ratio, so I think you will find that over 400 years the build up would be minor.

    The vast majority of such permafrost with peat in certain areas shows that those areas were more biologically active in the past, hence warmer.

  53. TCO
    Posted May 4, 2006 at 8:57 PM | Permalink

    Where is a bootleg copy of the draft. I can’t be arsed with a password. 🙂

  54. Dave Dardinger
    Posted May 4, 2006 at 10:50 PM | Permalink

    So, roots were buried (maining a hole was dug) and that proves that it wasnt permafrost there because there were roots so stuff must have been growing? Or was it cut roots on the edge of the hole?

    Neither, Lee. I thought it was pretty clear. The body was buried in a shroud. Later people digging through permafrost found the grave and noted that there were roots which had been penetrated the shroud. Thus the timing was:

    1. Body buried.
    2. Warm period where roots grew into shroud.
    3. Cold period where permafrost formed (and roots couldn’t grow.
    4. Present where this was all discovered.

  55. Posted May 5, 2006 at 1:47 AM | Permalink

    Re #47:

    Who the hell is ET? Ed, Sid, Extra Terrestrial, or just ET?
    (sorry, but as non-English native speaker, I have some problems with abbreviations or fancy or uncommon real names)

  56. Posted May 5, 2006 at 2:12 AM | Permalink

    Re #48:

    Lee, in my (Flemish/Dutch) English feeling, burrying means as good digging a hole as covered (later) by other stuff. If permafrost is near the top soil (as still is the case in mid-west Greenland at Jacobshavn/Ilulisat), no graves are digged at all, but the bodies are laid upon the soil and covered with stones.
    The fact that in southern Greenland bodies are found in the permafrost upon a layer of roots, means that they could dig a hole deep enough, which is possible again today at some places, but at a higher level than in the MWP.

    I am not very interested into the policy or credibility of who writes what, only in the credibility and scientific value of what is written. My interest is if the MWP was warmer than today’s climate in Greenland or not. There are some hints for that, as the buried roots and the ocean mixing alludes to. But there is no definitive proof for that, as good as there is no (even less) definitive proof for the opposite…

  57. ET SidViscous
    Posted May 5, 2006 at 7:57 AM | Permalink

    No worries, I just don’t know where the d came from. And to be honest I can’t complain, I’ve forcibly changed peoples name on them in real life in the past. So the more I think about it if you want to call me Ed go ahead.

  58. George F
    Posted May 6, 2006 at 8:00 AM | Permalink

    Re #48

    Lee, you said

    That quote is from CO2 Science, and the point there was on the credibility of CO2 Science, which was spinning a story about how cooling reduces ocean production and helped end the norse settlements, even though the norse didnt eat fish, which is well known.

    Rather a rash und unsubstantiated thing to say. You might firnd this interesting and informative.

    From here
    “An initial study of 25 Norse skeletons suggested that, during the ca. 500 years the settlements lasted, the Norse Greenlanders changed their diet from a predominantly terrestrial diet to a more marine diet.”

  59. Lee
    Posted May 6, 2006 at 7:13 PM | Permalink

    RE the roots: There are many possibilities,bincluding shallow summer burial on top of permafrost. My point is that inbthe absense of specific analysis of soil buiding processes and rate in that soil, or indicatinos of original depth, this is in fact no evidence at all.

    If that ither stuff is there, it may be telling us something about depth of thaw for one season, whic is also no evidence in absense of info regardign current depths of thaw,a nd year to year variability in that depth.

  60. Lee
    Posted May 6, 2006 at 7:18 PM | Permalink

    re 58:

    George, Ive read that. “Marine” does not mean “fish.” We know the Norse ate marine mammals, mostly hunted during summer expeditions to calving grounds north of the settlements. There is also evidence that as local farm productivity declined, perhaps tbecaue of temps, but certainly inlarge aprt because of soil and browse degradation from erosion afer overgrazing, that they depended more on that source for meat; this is one part of that evidence.

    The mammal populations on those grounds would not be limited by the described upwelling, at least without good evidence that the upwellign area was a major feeding ground for those mammals.

    Not to mention that I dont see good evidence for a good link between alterations in the upwellign and local temperatures.

  61. TCO
    Posted May 21, 2006 at 11:51 AM | Permalink


    Dardie: are you one of those who like this kind of post? Note, Steve’s response in the top part…maybe I’m not so out to sea…

  62. Dave Dardinger
    Posted May 21, 2006 at 4:22 PM | Permalink

    Well, TCO, I don’t think it’s even been determined what kind of post this is. Myself, I was referring to the kind of post which has an interactive gimmick. You probably meant something else. I mostly replied to you just to let me use some alliteration. I suppose I could instead try decyphering your name, especially given your hint. .. Let’s see what would TCO = “not out to sea”. “Sea” = C “Not out to” = into So you’re a C programmer? Or could we apply the “not” to your initials and so it means to reverse the letters TCO = OCT. You were born in October? That’s cool, so was I. Am I close?

  63. TCO
    Posted May 21, 2006 at 4:27 PM | Permalink

    Yeah, I figured you were just being cute and might even share my disdain for the JohnA vice SteveM posts…

  64. Dave Dardinger
    Posted May 21, 2006 at 4:38 PM | Permalink

    Well, this is Steve’s blog. But JohnA deserves some perks for helping keep the place running. But what if it were TCO vs JohnA blogs? I hate to say it, but you’d lose out there, friend. I don’t need vulgarity and I don’t need orders on how things should be done and when.

  65. TCO
    Posted May 21, 2006 at 5:37 PM | Permalink

    I agree with all of that. And thanks for agreeing with me.

  66. Steve Sadlov
    Posted May 26, 2006 at 11:32 AM | Permalink

    Like stock picking, futures trading and knife edge book cooking, the attempt to predict future climate may have huge downsides. By overtly driving the masses to prepare for a warming future, serious damage may result, if in fact, the future is a cooling, not a warming one. I just posted the following on the ENSO thread at RC, we’ll see if they let it through:

    “No matter what one might conclude about causitive factors, on the West Coast, where I have spent my 40 plus year life, indeed, La Nina like conditions have seemed to increase. Winters have brought increases in low elevation snow events and increases in the wide and wild swings typical of “less droughty” La Ninas (well, less droughty for the coast north of about San Luis Obispo, that is …). Springs have become limited to non existent. Summers tend to have more onshore push, deeper marine layers and more “unseasonal” cold fronts and insider slider lows. We see more cold core systems earlier in fall. So, depending on which GCM you subscribe to, and depending on the extent to which you elevate arthropogenic modification of the atmospheric gas mixture as a causitive factor of specific long term dynamics, yes, La Nina may be a proxy, of sorts, of the AGW theory assuming it is true. Frightening thought – if and only if the AGW centric prediction of future climate is either not completely correct, or out right wrong, consider extreme scenarios which would result in a drastically (and painfully) different outcome than the prophecied sea level rise / climatic tropical expansion / northerly movement of species model. Flip that on its head and imagine it. Pretty rough stuff, and in my mind, even worse than the outcome of the global warming tipping point scenario. Colder may not be better! “

  67. JillB
    Posted Aug 25, 2006 at 3:06 AM | Permalink

    can anyone tell me please if there is any evidence that increases in atmospheric co2 has initiated any global warming episodes?

  68. KevinUK
    Posted Aug 25, 2006 at 6:24 AM | Permalink

    Hi JillB,

    Are you new to the whole issue of anthropenic global warming (man-caused GW) or not. I ask because the information/advice you will be given will depend on you answer. If you are a newbie then its best to start by researching on Google and following the links from one web site to another. That way you can read what you see and make up your own mind. After a bit of that go and read the IPCC 2001 Third Aassessment Report (TAR) and you’ll then be able to relate what you’ve previous read against what’s in the TAR. One word of warning, don’t just read press articles in the mainstream media, dig deeper than that.

    Happy AGW researching!


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