Talk:Temperature record of the past 1000 years

From Wikipedia, the free encyclopedia

You have new messages (last change).
 This article related to meteorology and/or specific weather events is part of WikiProject Meteorology and Weather Events, an attempt to standardize and improve all articles related to weather or meteorology. You can help! Visit the project page or discuss an article at its talk page.
Start This article has been rated as Start-Class on the assessment scale.
High This article has been rated as High-importance within WikiProject Meteorology.

Contents

[edit] POV label

I've added the POV label. It's especially the introduction - the first paragraph - whose current form is unacceptable. The papers by Mann et al. are increasingly problematic. Many errors have been pointed out by many authors, and Mann et al. had to publish an extensive list of errors in Nature. The method itself was recently shown to produce highly biased results - see September 30th issue of Science (Hans Von Storch). [1] [2] [3]

Many scientists would agree that we have a lot of material that is more reliable than Mann et al. This page in its current form is a piece of propaganda produced by the alarmists, and Wikipedia deserves a better page. --Lumidek 16:44, 6 Nov 2004 (UTC)

(William M. Connolley 17:19, 6 Nov 2004 (UTC)) Lumideks assertions above are inaccurate. The NPOV header is spurious. The Mann et al reconstructions are widely accepted by the climatology community, whereas the criticisms are not. To assert that "many authors" have pointed out errors is wrong: M&M have published a little-regarded critique; the von S paper is far more sensible but very new. Muller is merely parroting M&M, and L is wrong to imply that Muller is saying anything related to von S. Also, von S doesn't say the hockey stick is biased: just that it underestimates long-term variance: which is a very different thing. MBH indeed published a corrigendum in nature but that was a corrigendum to the methods and sources: not to the results. The Nature corrigendum explicitly states that the results are unaltered. This is stark contrast to McK, who recently managed to confuse degrees and radians and hence get the wrong results. And finally... as the article points out... the results of other authors agree with MBH, thus providing independent verification [4].
Adding long term variance to the temperature graph has the effect to eliminate the conjectures about the extraordinary warming in the 20th century - and it is exactly this unjustified conjecture that is promoted so much in this article, which is why this article is a POV. If the temperature fluctuated a lot, as other papers than those MBH-like claim, then the results of MBH are not true, and their promotion in most of this article is unjustifiable.
(William M. Connolley 19:40, 6 Nov 2004 (UTC)) The page shows results other than MBH, which produce similar results. If you know of reconstructions that differ substanitally from MBH, you haven't troubled to ref them.
As I understand well, you have not found any problems with Von Storch's paper in Science.
(19:40, 6 Nov 2004 (UTC)) Von S is a sensible chap. But his paper doesn't support the interpretation you've given. And the von S paper is very new.
Incidentally, this is the first time I am writing the name "Richard Muller" - so far, I consider Richard Muller to be a Slovak musician. ;-) Sure, I know the physicist, but I thought that he only wrote a semi-popular article explaining why global warming science is not hard science; has he done some actual piece of research?
(William M. Connolley 19:40, 6 Nov 2004 (UTC)) The RM I'm talking about is the author of the second link that you inserted above. Do you not bother read the stuff you link to?
When you say that "the results of other authors agree with MBH", you should also say that the results of yet other authors disagree with MBH.
(William M. Connolley 19:40, 6 Nov 2004 (UTC)) You keep saying this. When, one day, you actually provide a ref then maybe I'll take you seriously.
MBH was published to overthrow the old belief - or theory - that there has been intense medieval warm period, followed by little ice age, and so forth.
(William M. Connolley 19:40, 6 Nov 2004 (UTC)) This too is inaccurate and unhistorical. Before MBH, there were no long reconstructions of hemispheric T. Thats why it gets so much attention - it was the first (or one of the very first) quantitative estimates of hemi T.
There are just too many people who call the MBH-like texts "junk science", and I encourage you to consider these people seriously. The Russian Academy of Science labeled Kyoto, for example, as "scientifically unfounded nonsense". --Lumidek 18:06, 6 Nov 2004 (UTC)
(William M. Connolley 19:40, 6 Nov 2004 (UTC)) Ah yes, the ever reliable RAS. A point worth talking about. Clearly, tehy aren't influential - Putin rejected their foolish advice. More interestingly though, how did they reach their advice. Can you point to an authoritative position paper from them - or are you just quoting press releases from a few members? And can you point to any reports on what they based their opinions on?

I don't think there's any question that this article is POV - it actually links to someone's blog as if it were a continuation of the article itself! More importantly it tails off very badly. For some reason as the article progresses it concentrates more and more on Mann et al's work (specifically one work, for some reason). Then every work that criticises Mann's work is listed, but a specific criticism is made of each of these works. Then we launch into a whole section criticising Mann's main critics - McIntyre et al. Then we look at the Wegmann report, criticise the Wegmann report and give Mann and McIntyre's blog addresses - under an "Updates" section. This is a wiki - if it needs updating, we can update it easily. References should go in the references section - the presence of two of the protagonists blogs in the main article suggests, at least to me, a serious absence of NPOV. What other sources exist apart from Mann et al? Can someone include the findings of these? Otherwise we may as well rename the article "Mann and McIntyre" --Dilaudid 21:03, 4 December 2006 (UTC)

As a first step to pruning this debate down - can we cut the "he said" "she said" below?

McIntyre and McKitrick only audited the work of Mann et al. (1998), and made no assessment of the other studies that are broadly consistent with the results of Mann (1998). However, the findings from the Wegman report suggest that authors in the area of paleoclimate studies are closely connected and thus ‘independent studies’ may not be as independent as they might appear on the surface.

I don't think the Wegman report is relevant to M&M, I don't think that there is any suggestion that M&M audited other studies. Is there a more recent Mann et al so we can perhaps day M&M audited 1998 but have not looked at later reports? Worst of all this alludes to the existence of "other sources", and without specifying who they are it criticises them. It seems a bit strange! --Dilaudid 21:03, 4 December 2006 (UTC)

There is a big issue in balancing this article between temperature record, and MBH in particular. There is probably a lot to be said for an article dedicated to "the hockey stick controversy", but that would then gut this article of most of its criticism. As to your specific points above: Wegman adds nothing of value to the debate and might as well be removed entirely (but I doubt the skeptics would wear that). You are correct that M&M haven't published on other studies: but this is a good point to make; because even if you simply delete MBH from the picture, nothing changes William M. Connolley 23:02, 4 December 2006 (UTC)

[edit] Page name

(William M. Connolley 19:34, 17 Oct 2003 (UTC)) This page contains useful info, some of it added by me, but there's no way I'm going to add links to anything called "hockey stick graph", so I've renamed it to a more neutral title. Those who like the old one can continue to use the redirect, and that seems fair to me, esp since nothing links to the hsg.

ps: I got the move wrong at first and linked to ...1000years. (with a full stop). Hopefully this is now corrected.

I agree that Hockey Stick can continue as a REDIRECT. It's a term used chiefly (only?) by 'skeptics' (as you call them) - not 'enviros' (as your colleague Fred Singer calls them). BTW, can you think of any better terms for GW advocates than enviros & skeptics? --Uncle Ed 15:50, 21 Oct 2003 (UTC)

What is up with that graph? there are no units, and there is not even a scale along the bottom. If you add a graph, find one which has units and put a summary below for context. -- Catskul 2004 Feb 13

(William M. Connolley 17:02, 15 Feb 2004 (UTC)) Replaced graph with the ready-to-slot in replacemetn, why couldn't you bother? See http://en.wikipedia.org/wiki/Image%3AGlobwarmNH.png and http://en.wikipedia.org/wiki/Image%3AMBH98_SEW_drawing311.png

[edit] Misc

(William M. Connolley 20:50, 20 Oct 2003 (UTC))

Changed "about 1 oF (0.4 to 0.8 oC)" to "about 0.6 oC". There is no point giving 2 temperature units everywhere, and oC is better (err - there must be some kind of wiki policy on this, I wonder what it might be?). 0.6 not range, not to attempt to suppress uncertainty, but because thats covered elsewhere and is not the point of this page.
replace "used by the IPCC" with "these"; add "quantitative" to first para. The point being, its what these graphs show, whether used by IPCC or not.
Add para re qual/quant distinction, which inevitably makes the quant records sound superior. Partly because they are; partly because they are more amenable to analysis.
Wasn't the Maunder Min a period of low sunspot activity, first, and a cold period, second?
I don't think the sunspot record goes back into the MWP but leave this for now.


[edit] Hottest year

From text:

The work of Mann et al. and others [5] forms a major part of the IPCC's conclusion that atmospheric temperatures had been on a slow, gradual downward trend until the 20th century when greenhouse gas emissions caused temperatures to increase at an unprecedented rate; and that the present warming is unusual within the last 1000 years. It also shows that 1998 was the hottest year in the record.

Saying that Mann's "work...shows that 1998 was the hottest year" implies that Mann's work is reliable and honest, since it shows a "fact". But Wikipedia ought not to endorse Mann's claims like this. We should not use authoritative language which implies that these are objective "findings" of impartial searcher of truth.

Rather, we should say that the data Mann selected and arranged bolster his contention that temps were flat until recently, and that his graph presents 1998 as the hottest year -- rather than saying that his work proves that 1998 was the hottest year.

Another paper, which I'll cite in a moment, thoroughly discredits his work as little better than a fabrication -- okay, maybe he made an honest mistake, but it's at best shoddy work. He didn't take enough data points, and he simply ERASED the medievel warm period because it didn't fit in with his pre-ordained conclusion.

This division of quantitative (proving Mann and IPCC right) vs. qualitative (uninformed speculations of skeptics) is just UN/enviro POV. --Uncle Ed 21:17, 24 Nov 2003 (UTC)

(William M. Connolley 22:44, 24 Nov 2003 (UTC)) You still don't inderstand qual/quant. Keep trying.

<grin> Well, doc, it would help if you explained the distinction better. How about writing a short article? --Uncle Ed 22:59, 24 Nov 2003 (UTC)

[edit] Recent papers

We should probably add the two recent papers attacking the conclusions by Mann et al.

This one by Soon et. al. (There are actually two papers that are substantially the same)...

http://www.kolumbus.fi/boris.winterhalter/EnEpreprintFeb03.pdf

They had it published in "Energy & Environment", which is notable see this excerpt from 'Chronicle of Higher Education'

http://www.davidappell.com/archives/00000293.htm

another discuss at Eureka alert

http://www.eurekalert.org/pub_releases/2003-07/agu-lcs070703.php

and the actual response by Mann et. al.

http://www.agu.org/journals/eo/eo0327/2003EO270003.pdf#anchor

The second paper of interest is

http://www.multi-science.co.uk/mcintyre_02.pdf

again pulblished in 'Energy & Environment'

by McIntyre and McKitrick

and here is the rebuttal by Mann et. al

http://holocene.evsc.virginia.edu/Mann/EandEPaperProblem.pdf


(William M. Connolley 01:17, 9 Dec 2003 (UTC)) Yes. But some of that is already somewhere... oh yes, on Michael_Mann_(scientist) (Ed Poor started it...). I would actually prefer it to stay there, perhaps augmented: at the moment, the value of M&M is very much in debate, and is more of a "challenge to Mann" (and hence approprite to his page) than a contribution to the T record (my POV). The S+B paper(s) are junk... I'd rather not pollute wikipedia with them. They are of no value to the T record pages... perhaps under global warming controversy? Somewhere.

I realize they are junk, but my concern is, that skeptics will have heard of the papers (due to media saturation), but have doubtfully heard the refutations. Thus if we fail to mention the papers and fail to explain the problems with them, I suspect either readers will doubt the NPOV, or will assume we are ignorant of the papers.

(William M. Connolley 13:59, 13 Dec 2003 (UTC)) In which case probably the best thing to do is to start a page about just that paper (poss a bit too specialised), or a page about Soon or Baliumas (do they have one already?), or dump it into the hell-hole that is global warming controversy, or... Well, if you want to write up the S+B papers, good luck to you, whereever you put it.


[edit] Re-balancing

(William M. Connolley 21:19, 5 Feb 2004 (UTC)) I've de-skepticised the page somewhat, and added a rebuttal from Mann to M&M (forgetting what was on this very talk page about using the Mann page...

Firstly, I've re-instated *all* quant recons. I'll repeat what I said to Ed: you want to get rid of all, you have to find one that says otherwise (and no, M&M doesn't count, can you guess why?).

I cut the "belies activist claims" stuff: what was that there for?

John Dalys page doesn't describe skepticism, it pushes Dalys POV; hence rewording.

Re M&M, I've collapsed it somewhat, in particular making the de-listing the list, because it doesn't (yet) deserve the expanded space. But all the items in the list are still there.

[edit] FUD from Soon et al.

(William M. Connolley 19:35, 4 Jul 2004 (UTC)) OK, a POV header perhaps...

Fear is irrelevant to science. Uncertainty and doubt are hardly surprising when there are many unknowns. FUD is a marketing term, so it depends on what is being sold. -- (SEWilco)

Para removed from page:

There are difficulties also in presentation of the recent instrumental record, which is often shown near the end of temperature reconstructions.
  • Soon, Legates, and Balunias pointed out in 2004 that they were able to replicate the instrumental surface temperature trends as shown in several studies.
    • However, they were unable to reproduce the long-term Northern Hemispheric surface temperature trends in Figure 2.21 of IPCC TAR and Figure 2a of (Mann and Jones [2003]). It should be possible to duplicate the results of such a study.
    • During one year, three related studies show an increasing temperature change, with the change increasing at the extremely rapid rate of about 1 to 2.5 °C per decade. The authors of those three studies were showing that during the year that their studies had produced increasingly larger rates of change. Each study showed that temperature was increasing ever more quickly. Soon et al. found no justification for the high value in the last paper (Mann and Jones [2003]).

The Soon study is a bit weird. They repeatedly talk about claims of 1oC/y or whatever - a claim made by nobody but them.

(SEWilco 04:05, 6 Jul 2004 (UTC)) They say the claim is in the figures.

As to their problems in 2b - look at it. THe green line looks like a better fit to the data than the red.

(SEWilco 04:05, 6 Jul 2004 (UTC)) It looks like a better fit, but it won't be if next year is much warmer or colder. Just as the green line would be too high or low on a graph ending in 1931 or 1940 (without using data in the future of that date), due to the obvious change in trend in those years.

The paper appears to be FUD. The *calculation* of the trends isn't done from reading lines off graphs so its all quite irrelevant.

(SEWilco 04:05, 6 Jul 2004 (UTC)) Soon's calculations also were based on real data, but could not duplicate the trends shown without finding problems. As you say, there are trends shown in the figures.
(SEWilco 14:30, 5 Jul 2004 (UTC)) - WMC knows most of this, but I show more detail here for other readers.
Looks to me like they got the trends from the slope of the lines on the graph, and they are looking at the rate of change shown for very recent years. They started with formal instrumental data and tried to duplicate the published graphs. But using the last year's data as the average for the next 20 years is not a reliable way to get the pretty line to the end of the paper. As the article states, we don't have information about future events so the method which involves 20 years in the past and 20 years in the future produces a graph which should end 20 years before the end of the data. Pushing the line to the last year involves increasing uncertainty.
Yes, I see in 2b (page 3 of Soon's paper) that the green line looks nice. But if the graph is cut off at 1941, the green line would go upward and away from what actually happened. If the graph is cut off at 1930, the green line would go downward from what actually happened.
(SEWilco 14:39, 5 Jul 2004 (UTC)) Reinserted in the article the paragraph about Soon's study.
(SEWilco 04:05, 6 Jul 2004 (UTC)) Rereinserted another version of Soon paragraph.

(William M. Connolley 08:37, 6 Jul 2004 (UTC)) This is silly. Soon et al come to the grand conclusion that:

concluding that there are problems in recent suggestions of an extremely rapid rate of about 1 to 2.5 °C per decade

BUT THIS SUGGESTION IS ONLY MADE BY SOON ET AL. Not by anybody else. They are rebutting their own nonsense! FUD removed again.

(SEWilco 16:07, 6 Jul 2004 (UTC)) The suggestion is from the published figures.
(William M. Connolley 16:30, 6 Jul 2004 (UTC)) Thats why its FUD, not an outright lie. Soon et al are trying to give the impression that people have been saying that the recent T trend is 1-2.5 oC/y. This is nonsense, only Soon et al are saying this so they can create a strawman to knock down.
(SEWilco 08:02, 7 Jul 2004 (UTC)) It's not the T trend which they refer to. It's the rate of change of the T trend during the year 2002-2003. The illustrated T trend increased by as much as 0.25°C/y during a single year. 0.25 * 10 years = 2.5
(William M. Connolley 16:06, 7 Jul 2004 (UTC)) I don't know where you get this weird interpretation from. I don't find it in the paper. And the tech central article talks about "the extreme warming trend of 1 to 2.5 oc/decade...". Thats a trend, not a rate of change of trend. Mann et al (despite Soons insinuations) don't say this. Nor does theor figure c support it either. Their figure c appears to show 0.5-0.6 oC in about 2 decades. Furthermore, the assertion (lower down) that T trend estimates are quite arbitrary is total cr*p. They have failed to distinuish (perhaps to even understand) the different between lines on a graph and fitting trend estimates. I do hope that you understand this.
(SEWilco 17:01, 7 Jul 2004 (UTC)) That's why I mentioned 0.25, so you can search the PDF: look at the end of paragraph [3] on page 1 of Soon, paragraph 13 on page 3, and 19 on page 4.
(SEW) The figures are a statement of trend, as you recognized when you commented one trend line looking like a better fit.
(William M. Connolley 16:30, 6 Jul 2004 (UTC)) No, the statements of trend are the numerical numbers quoted in IPCC and elsewhere. But Soon et al can't touch those, so they have to create strawmen instead.
(SEWilco 08:02, 7 Jul 2004 (UTC)) The numbers and methods don't all match the illustrations. Although not all the numbers and methods are available, or are not stated correctly. Are there really enough numbers to show what the illustrations show? Often studies use illustrations as summaries, and extracting data from them is done often enough that there is software to do that.
(WMC) As to the lines and the fit... yes Soons lines don't seem to fit very well.
(SEW) There should be no problem replicating the studies, so the lines should fit. You know how science works.
(SEW) The studies present a pattern, rather than just the raw data, but in some cases the pattern is not supported. Soon's point is that the calculation of the fit is unexplained or seems to be based on artificial future temperatures
(WMC) This is a (minor) signal processing matter. People drawing average lines through noisy data like to get to the end. Which you can't do by simple averaging.
(SEW) These people seem to not agree how to reach the end. Even when one of them is working on all three drawings. As Soon says, they should better explain their methods.
(SEW) , and more information should be given with such figures. Thus I am pointing out that there are problems with the representation of temperature records. Review and replication of studies is part of the scientific method, including failed replication (ie "cold fusion").

Are any of the above issues unresolved? Which? (SEWilco 07:48, 17 Jul 2004 (UTC))

(William M. Connolley 21:31, 24 Jul 2004 (UTC)) Back from hols... anyway: my central point is that Soon et al is FUD (I only say that to explain my overall view of its: I'm not pretending its a complete criticism in itself). Anyway, the unresolved points are: is the 1-2.5 oC stuff referring to T trends or to increases in T trends; where anyway do S *get* this value from; and why its a valid criticism when they are the only people saying it. There also seems to be some confusion that S are encouraging about the *computation* of T trends as opposed to their *display*: the end-padding S talk about is irrelevant for the computation.

(William M. Connolley 08:56, 27 Jul 2004 (UTC)) I've added comments below, but this is going round in circles.
  • The 1-2.5°C is increase in T trends. That is, the published trends are showing increasingly higher trends for the same period. They also say that they found no justification for one high value, so they obviously got the value from the chart because they can't duplicate that result. The Tech Central Station article shows that they couldn't get an explanation of how to duplicate it, other than some "circular explanation".
(William M. Connolley 08:56, 27 Jul 2004 (UTC)) The only people talking about 1-2.5 oC stuff are Soon et al. No-one else. They are just making these claims to knock them down: strawmen.
(SEWilco 15:59, 27 Jul 2004 (UTC))
  1. Do you see that those 3 graphs do not end the same way?
    1. If you don't see the graphs are different then let's examine them more closely.
    2. If you see the graphs are different then you're now one of those who has observed there is a difference in the published trends.

(William M. Connolley 19:38, 28 Jul 2004 (UTC)) This is where you have failed to understand the difference between drawing pretty lines on graphs, and the published temperature trends. When IPCC says the trends over the last century are 0.4-0.8 oC (or whatever) they are *not* reading the lines off graphs. They are going it by LS fit or somesuch. Which don't suffer from any of this nonsense. Do *you* understand that.

(SEWilco 05:08, 29 Jul 2004 (UTC)) Yes, if Dr X reports a range like that then it is from the results of his calculations; he might also show results on a graph but he is producing the graph from his numbers. However, if he only publishes the graph and not the numerical results then all he's offering is for us to read the lines off the graph. The graph can be studied, just as similar graphs from analog instruments can be studied.
      1. Measure the differences in the endpoints of the graphs.
        1. I see trends of 0.3, 0.41, and 0.55 °C per decade. Do you see similar values?

(William M. Connolley 19:38, 28 Jul 2004 (UTC)) Don't do this!

(SEWilco 05:08, 29 Jul 2004 (UTC)) What do you want us to do? If the numerical results are available, we can use those. Perhaps Soon et al. used numerical result data sets, although the references only mention the published studies. Aren't published studies what you say should be used as authoritative sources?
(William M. Connolley 09:21, 29 Jul 2004 (UTC)) What do I want you to do? I want you to calculate trends by LS fits to data, not by reading wiggly lines off graphs by eye.
(SEWilco 15:36, 29 Jul 2004 (UTC)) You indicated a lack of understanding where the 0.1 and 0.25 came from, so I presented a back of the envelope method. If you don't want to eyeball the graphs, dump their numerical representation of their results in your spreadsheet and compare the numbers. Are you getting values which are significantly different?
(William M. Connolley 15:55, 29 Jul 2004 (UTC)) You have misunderstood me. You said, you were getting trend values by eyeballing wiggly lines. I said, this is a poor method of deriving trends, amongst other reasons because it suffers from the end effects that so excise Soon et al. If you want to derive trends, do what all sane people do and derive them from fits to the original data, which doesn't suffer from these problems.
(SEWilco 05:02, 1 Aug 2004 (UTC)) So have you found yet that the three graphs show final trend values which differ? I don't care whether you want to use the red pixel on the image or numerical data. I'm just asking if there is a difference, the amount of difference is the next item.
        1. The differences are about 0.1 and 0.25 °C per decade. Do the math yourself because reproducibility of results is important.
        2. The three studies appeared in one year.
          1. I don't see mention of when the studies were authored, so the differences in publication date seems to be used instead of the actual times.
          2. The change in trends of 0.1 and 0.25 within one year are projected as changes of 1 and 2.5 per decade. The decade timescale matches that used in the studies.

(William M. Connolley 19:38, 28 Jul 2004 (UTC)) Indeed. This is where the total twaddle comes in. Thanks for explaining it so clearly - I hadn't realised that Soon et al were really dumb enough to do this.

          1. 0.1 change in a year * 10 years in a decade = 1 / decade
          2. 0.25 change in a year * 10 years in a decade = 2.5 / decade
        2. If your calculations also show 1-2.5 then now you are also making the claim. It's no longer only Soon et al.
  2. Quantity of participants does not determine a straw man, it is the ingredients. In which of the above steps is straw growing?
  • The number of people saying something does not affect whether it is true or not -- are the charts for the same period the same or not?
  • The computational issues are an attempt to figure out what causes such differences, but the differences are there whether explained or not. This study shows there are difficulties in dealing even with the very newest temp records. -- (SEWilco 06:05, 25 Jul 2004 (UTC))
(William M. Connolley 08:56, 27 Jul 2004 (UTC)) Let me take this very very slowly as I'm clearly not getting through. (1) If you want to draw pretty lines on a graph of smoothed data, then you need to do something to "pad it to the end" if you want the smoothed lines to go to the end. There is no unique way to do this. (2) If you want to calculate the trend in a series then point one is TOTALLY IRRELEVANT because the trend can be and is calculated without any need for padding. I don't understand what you mean by "there are difficulties in dealing even with the very newest temp records".
(SEWilco 15:59, 27 Jul 2004 (UTC)) (0) The published trends are different.

(William M. Connolley 19:38, 28 Jul 2004 (UTC)) No. The wiglly lines are different. The published trends aren't.

(1) The same method of smoothing should be used, so the results from all three similar studies should be the same. Instead 3 studies show increasing trends, so differences were examined, and one could not be duplicated. (2) The padding was examined in an attempt to duplicate the published results, as the published studies showed the trend was changing although the data was not.

(William M. Connolley 19:38, 28 Jul 2004 (UTC)) But this is where the total nonsense occurs. Different smoothing leads to different wiggly lines. They might go up, they might go down. Only Soon et al are dumb enough to create a fake time series from these different wiggly lines. Wikipedia should have nothing to do with this.

(SEWilco 15:36, 29 Jul 2004 (UTC)) Soon et al had to use most of their paper to show that "different smoothing leads to different wiggly lines".
(William M. Connolley 10:17, 1 Aug 2004 (UTC)) No. Different smoothing leading to different lines is obvious.
They had to do this because others produced a fake result of their wriggly lines. If you're going to call Soon's study fake, then that term should apply to the result which Soon found "unjustified". Should Wikipedia have nothing to do with Mann and Jones (2003)?
(William M. Connolley 10:17, 1 Aug 2004 (UTC)) Sigh. You're being silly here. Soon et al have produced a fake timeseries, if your description above is accurate. You say, they have produced a timeseries from differences in other peoples wiggly lines. But those differences in wiggly lines are not well fixed in time (as you say above) and aren't really a time series anyway: they could just has easily appeared in another order had publication dates been different.

[edit] FUD from Kyoto supporters

Wilco and William, please stop sparring a moment and help me write about why the IPCC orginally used a temperature graph that showed the Medieval Climate Optimum but then changed to using a temperature graph which conceals that warm period. --Uncle Ed 19:37, 1 Oct 2004 (UTC)

(William M. Connolley 20:27, 1 Oct 2004 (UTC)) Welcome back to climate, Ed. But you've been away a while: take a time to familiarise yourself with whats already on the pages before you rush in: in particular the section "Skepticism and rebuttals thereof" subsection "Historical temperature estimates".

[edit] Bias

If anyone censors the report of M&M's findings about bugs in Mann's hockey stick program, then I will put the "neutrality disputed" notice back up. "I'm a lover, not a fighter." --user:Ed Poor (deep or sour) 17:32, Nov 11, 2004 (UTC)

(William M. Connolley 19:07, 11 Nov 2004 (UTC)) M&M's findings are unpublished. See-also http://www.wmconnolley.org.uk/sci/mbh/ if you want some detail. I've just had a look at your additions, which confirm my worst fears. You cannot possibly get away with dumping a pile of undigested skepticism, not even from a published paper, into the intro of the article. Try putting it somewhere sensible, or better still here, and we can talk about it.

Well, you've certainly given me something to chew on, doc. But I don't swallow it. Just what exactly is the flavor of your discontent? Wikipedia is not a refereed journal. I can put in any skeptical remark I like, as long as the source has SOME credentials related to the issue. --user:Ed Poor (deep or sour) 21:18, Nov 11, 2004 (UTC)

(William M. Connolley 21:30, 11 Nov 2004 (UTC)) I'll repeat myself (and []) then: You cannot possibly get away with dumping a pile of undigested skepticism, [which is] not even from a published paper, into the intro of the article. Try putting it somewhere sensible, or better still here, and we can talk about it.. You have a bad history of doing this: adding material that (although dubious) might survive lower down in a sensible section but which cannot possibly justify being in the intro.

Are you throwing down the gauntlet now? Let's do this properly, and have your friends arrange the matter with my friends. Pistols at dawn? Icicles at noon? How about a spaghetti-eating contest? Cool off, man. Go outside and breathe some cool British air. --user:Ed Poor (deep or sour) 22:21, Nov 11, 2004 (UTC)

(William M. Connolley 23:04, 11 Nov 2004 (UTC)) This isn't war. There is space for the most recent McK stuff (properly qualified). But it doesn't belong in the intro.

This paragraph is meant to confirm that the debate is going on, and actually our side - that insists that these graphs should not be presented as facts - constitutes a majority in this debate. William, it would be nice if you took this observation into account, and if you either allowed the critical remarks about the MBH graphs to appear in the introduction, or accepted the POV label. Concerning newer material along these lines, please don't forget von Storch's recent article in Science. The MBH graphs are very far from an established piece of science. --Lumidek 22:15, 14 Nov 2004 (UTC)

(William M. Connolley 22:21, 14 Nov 2004 (UTC)) Putting the M&M stuff into the intro is absurd - its not even published material. And even if it was, putting the entirety of the quote into the intro would still be absurdly unbalanced. Von S is another matter - feel free to introduce von S into the text.
OK, I would be happier if you introduced von S yourself - unless the truth about the record has been showed to you by God, my particle physicist's understanding of the word "science" dictates that the observations of von S are important for this story. Moreover, if the fluctuations by von S are confirmed, I will really think that M&M should take more credit for it, but that's a different issue. At this moment, I find the article plausible - at the edge - so I won't reintroduce POV. --Lumidek 22:55, 14 Nov 2004 (UTC)
(William M. Connolley 23:09, 14 Nov 2004 (UTC)) Von S and M&M are orthogonal. This is an encyclopedia, not a newspaper - news requires time to settle down. Von S hasn't. Its in Science, true, but very recently. How would you have reacted if I'd put Vinnikov and Grody down as definitive rebuttal of S+C's MSU stuff?
Von S and M&M are not orthogonal, and both are about the underestimated fluctuations in the past by Mann et al.


(William M. Connolley 10:02, 15 Nov 2004 (UTC)) But there is no connection between their approaches. Neither supports the other.

As you can see, there has not been enough time for Mann et al. to settle down either, and I think that they will not settle down anymore. ;-) I am surprised by your focus on the appearance of various texts in journals. This is certainly not a strategy that I would expect from someone who understands the field although it may be a good strategy for a laymen to choose the right information. However, if a physicist told me that he decides whether a paper is correct or not according to the journal where it appeared (i.e. she or he trusts the referees), I would conclude that the physicist probably does not understand the material herself. Do you actually understand something about climate science, or are you just a science fan that trusts those experts who are able to publish in well-known journals? Although you are very active and visible at all these pages, I have not understood this point so far. To be sure, I want to answer all your questions, so here's the last one. If you decided to put Vinnikov and Grody in this article, I would erase it because it has nothing to do with temperature in the last 1000 years - rather last 25 years as measured by satellites. I am open-minded whether the surface measurements agree with the satellites, and I agree that Vinnikov and Grody are too new for us to be sure about the outcome, especially if we're string theorists like me. ;-) Yes, as you probably guess correctly, I lean to the opinion that the surface measurements are biased by human activity, and the satellites can show much less change, but it's certainly not a dogma for me. --Lumidek 23:27, 14 Nov 2004 (UTC)

(William M. Connolley 10:02, 15 Nov 2004 (UTC)) Ah, excellent: you've managed to see the point: V+G is too recent. But its older than von S.

Thank you for your compliments. Things can be recent, but they will not be recent in the future. I think that you know very well that in a couple of years, when the dust settles, Mann et al. most likely won't be viewed as a good piece of work. You just try to slow this process down.--Lumidek 12:40, 15 Nov 2004 (UTC)

[edit] MM05

Redirected discussion from Talk:Global_warming

I think that there is going to be a storm of controversity when MM05 is published in February.

The Financial Post:

Breaking the Hockey Stick - Part 1

http://www.canada.com/components/printstory/printstory4.aspx?id=108c0400-4e71-4c55-a279-dd43aed1f224

The lone Gaspe cedar - Part II

http://www.canada.com/components/printstory/printstory4.aspx?id=052554eb-ebdb-483a-8f28-c4ce19458973

--D Norris 15:43:55, 29 Jan 2005 (UTC)

(William M. Connolley 16:30, 29 Jan 2005 (UTC)) Thats nice. Lets wait till its actually published though shall we? And lets remember that the MBH results are replicated by independent studies too, shall we? Since we're all recommneding our favourite reading, I recomment to you http://www.realclimate.org/index.php?p=114, http://www.realclimate.org/index.php?p=111 and indeed many of the other posts at RealClimate.
For those that want a sneak peak at what is being published in Geophysical Research Letters next month: http://www.climate2003.com/pdfs/2004GL012750.pdf GRL, by the way, published Mann in 99 as well. --D. Norris 17:25, Jan 29, 2005 (UTC)

Hmmmmm ----

In January, 2005, an adapted version of McIntyre and McKitrick's paper was accepted for publication by Geophysical Research Letters (GRL). Judging by the reactions of the referees of GRL, which McIntyre made available to us, the tide may be turning in the climatology field. One referee stated: "S. McIntyre and R. McKitrick have written a remarkable paper on a subject of great importance. What makes the paper significant is that they show that one of the most important and widely known results of climate analysis, the 'hockey stick' diagram of Mann et al.,was based on a mistake in the application of a mathematical technique known as principal component analysis (PCA)."

The same referee also writes: "McIntyre and McKitrick found a non-standard normalization procedure in the Mann et al. analysis. Their paper describes this procedure; it was an apparently innocent one of normalization, but it had a major effect on their results. The Mann et al. normalization tends to significantly increase the variance of data sets that have the hockey-stick shape. In the Mann et al. data set, this turned out to be bristlecone pines in the western United States. Thus the hockey stick plot, rather than representing a true global average of climate for the past thousand years, at best represented the behavior of climate in the western U.S. during that period. This is an astonishing result. I have looked carefully at the McIntyre and McKitrick analysis, and I am convinced that their work is correct."

The referee ends with: "I urge you not to shy away from this paper because of its potential controversy. The whole field of global warming is currently suffering from the fact that it has become politicized. Science really depends for its success on an open dialogue, with critics on both sides being heard. McIntyre and McKitrick present a cogent analysis of the global warming data. They do not conclude that global warming is not a problem; they don't even conclude that the medieval warm period really was there. All they do is correct the analysis of prior workers, in a way that must ultimately help us in our understanding of past climate, and predictions of future climate. That makes this a very important paper. I strongly urge you to publish it." - The lone Gaspe cedar [6]

--D. Norris 19:01, Jan 29, 2005 (UTC)

I discuss the article MM05 on my blog [7] which also contains the links to the paper itself, and articles about it. Maybe we should try to be nice to these people. They will definitely be in an existential crisis. Starting from February, they may have no future. They will be identified as the leaders of the most costly scientific fraud in the history of the humankind. I think that M&M will become pretty famous. Many people experienced in statistics will quickly follow, and they will most likely identify the problems with all the other similar climate papers. These papers are not really independent. They share the same authors and the same methods, so my guess is that they will collapse easily - the main "argument" behind them was a "consensus" - a consensus among the people neither of which bothered to verify the key calculations. A consensus among very weak scientists. In fact, Mann et al. was the most transparent paper where the algorithm they used to obtain the results could be partially followed. Other papers are much worse. If someone predicted that Mann will commit suicide before March 2005, it would be hard for me to argue against it. It is certainly much much more likely than a climatic disaster in the next 50 years. ;-) This guy is kind of doomed, and William's situation is not much better. William, please don't give up your life - and enjoy the last weeks of your life in which the people are not spitting at you on the street. ;-) There is always a chance for you to start a new life - a life without scientific fraud. All the best, Luboš --Lumidek 20:44, 29 Jan 2005 (UTC)
(William M. Connolley 21:12, 29 Jan 2005 (UTC)) I suggest you read the RealClimate posts.
Dear William, be sure that I've read them - although an outsider, I am simply interested in this topic. Having read them does not imply that they make as much sense as the new paper by M&M which is pretty brilliant and powerful. Your article on rc.org are pretty lousy, they have really nothing to do with the technical findings of M&M, and you must really believe that all other people are complete idiots if you think that they won't be able to identify whether MM or rc.org make more sense. Enjoy the last weeks of your consensus of lies! Saddam also tried to enjoy the last weeks. ;-) --Lumidek 21:35, 29 Jan 2005 (UTC)

More from The Financial Post: http://www.canada.com/components/printstory/printstory4.aspx?id=db3b26e9-edb9-417c-ab92-fa78432433bf

For instance, in 2004, scientists in the journal Geophysical Research Letters concluded that Mann and Jones' methods were "just bad science" and that they had undertaken a "selective and inappropriate presentation" of results.

In June, of 2004, the accumulated weight of criticisms led to a retraction by Mann (and Scott Rutherford) in the Journal of Geophysical Research. However, while Mann admits to substantially underestimating historical temperature variations he claimed that it had no effect on his conclusions.

If even one component of Mann and Jones' -- and, consequently, the IPCC's -- temperature reconstruction is in error, then we can't say with any confidence that the 1990s were the warmest decade of the last two millennia, or that 1998 was the warmest year, much less that the last century's rise in temperature is unprecedented.

How interesting! --D. Norris 13:33, Feb 1, 2005 (UTC)

[edit] Current

Dear Gentlemen, I hope that many of you will agree that the label ((current)) is gonna be pretty appropriate for this page. ;-) --Lumidek 03:17, 31 Jan 2005 (UTC)

(William M. Connolley 09:54, 31 Jan 2005 (UTC)) Who knows, it might be one day, but it certainly isn't now.
Dear William, that's a great strategy to postpone all these things, hide, combine, and recombine your defense. But remember that February only has 28 days. ;-) For others - this "current" was partly a joke, and if it's difficult to keep it, don't waste much time with it. But if they publish MM05 and something starts to happen, the tag may be appropriate. --Lumidek 14:54, 31 Jan 2005 (UTC)
(William M. Connolley 15:17, 31 Jan 2005 (UTC)) These pages are controversial enough. Wasting time starting joke edit wars is inexcusable.
I have not started any edit war. As someone who cares about your doomed future, I'm just slowly preparing you for what is gonna happen very soon. ;-) BTW have you heard the sad news plus good news from Virginia that finally they stopped him and I must still wait for my 10,000 dollars? ;-) --Lumidek 15:29, 31 Jan 2005 (UTC)
(William M. Connolley 16:39, 31 Jan 2005 (UTC)) Hopefully you haven't, but Norris seems to be blindly following you, before realising you were only joking. As for Virginia... what are you talking about?
I never blindly follow anyone. If I did, I would blindly accept the pronouncements of the IPCC and march in lock step with the 'scientific consensus', but I was trained to question everything, especially the opinions of the herd.
I happen to think that this topic is going to start changing very rapidly in the next month and warrents a 'current' disclaimer. But I am willing to wait for MM05 to be published.
Oh, BTW, it is 'Ms Norris' to you, Doctor! But if you are polite, you can call me Denise. --D. Norris 13:40, Feb 1, 2005 (UTC)
You made a mistake by re-inserting Lumideks joke but are too graceless to admit it. Noted the Ms.
I agree with Lumidek 100% on the use of 'Current'. Please allow me to refresh your memory as to his exact words:
For others - this "current" was partly a joke, and if it's difficult to keep it, don't waste much time with it. But if they publish MM05 and something starts to happen, the tag may be appropriate.
Hmmmm... I admit everything with aplomb and grace. --D. Norris 19:50, Feb 1, 2005 (UTC)
Perhaps all of you want to read why the "current label" was invented: Template talk:Current. IMHO the number of edits is by far not on the same level as 11 March 2004 Madrid attacks and thus does not justify the current tag. -- mkrohn 00:08, 2 Feb 2005 (UTC)

[edit] The introduction

This article needs an introduction. The name "Temperature record of the past 1000 years" implies objective fact - as if there were an actual, documented record of temperatures over the past millenium. However, this article is simply a collection of theories. This needs to be stated clearly and unequivocally in the introduction.--JonGwynne 01:11, 8 Feb 2005 (UTC)

I tend to agree that the old introduction is not the best one, but I also think that the current one is not better. We don't need to explain what a theory is, better link to theory instead. Also I wonder about the usage of the word "assumption" in your text "the assumption by scientists of what the temperature record may have been". May I ask what your background in science is? As I said changing the current intro is fine with me, but the one your propose sounds strange to me - sorry -- mkrohn 01:50, 8 Feb 2005 (UTC)
I agree that we don't need to explain what theories are, but we do need to explain that this page is theory and not fact. The title makes it sound like fact and not theory. If you have a better idea for an intro that explains this, then feel free to add it or change mine to suit. But, I'll take another crack at it for now since there has to be one.--JonGwynne 01:55, 8 Feb 2005 (UTC)

[edit] Moberg et al.

I am not going to try to make any changes to this or related articles myself, because frankly this battleground is no fun to play in, but I would like to point out the paper by Moberg et al. appearing in today's Nature (Feb. 10, 2005). The link is [8] for those with online access to Nature.

The paper is an attempt to redo the temperature history of the last 1000 years based on what the authors regard as a growing recognition that the methodology of Mann et al. and similar studies systematically surpress centennial scale variability. Their results, using a revised methodology, show both a medieval warm period and a little ice age. They are also consistent with the scale of natural variability reported from borehole measurements, while Mann et al. wasn't. However, they still regard the warming during the last several decades as unprecedented and inconsistent with natural variability.

Dragons flight 18:55, Feb 10, 2005 (UTC)

For those who have no access to nature: the graph is similar to Image:GlobwarmNH.png with the two exceptions that "Dragons flight" already pointed out: the graph which shows years 0-2000 touches 0 degree about 1000 AD and goes down to about -0.7 degree around 1600 AD. It seems (though I am not an expert) that the graph is a refinement of Mann et al. but tells us qualitatively the same thing. Quote from the paper: "We find no evidence for any earlier periods in the last two millennia with warmer conditions than the post-1990 [...]" -- mkrohn 19:44, 10 Feb 2005 (UTC)
(William M. Connolley 21:05, 10 Feb 2005 (UTC)) I haven't read it, but probably will tomorrow. I presume its good science - Nature usually is - but I would like to caution that wiki is an encyclopedia; a place for well-considered results; and things just-published don't usually belong (arguably the von S stuff falls into this category, but I know the howls of protest that would occur if I tried to remove it :-).

[edit] Hockey Stick disinformation

This article needs attention. The discredited theories of "hockey stick" created by the "hockey team" should be rewritten as a historical discussion of the myths that were believed at various points, and the more correct and up-to-date sources like Moberg et al. and M&M should replace the "mainstream" discussion. Best, Lubos --Lumidek 01:51, 11 Feb 2005 (UTC)

(William M. Connolley 09:51, 11 Feb 2005 (UTC)) Thank you for making your biases so obvious.
You may call it "biases", but the more important thing is that it is reality. This article has been kind of completely flawed, and it is necessary to re-make the whole text. --Lumidek 15:01, 11 Feb 2005 (UTC)

I don't feel as strongly as Lumidek apparently does, but I do think that the presentation of this article needs some attention. I am inclined to think that this article would be better served if it moved away from the hockey-stick / not-a-hockey-stick mentality. MBH was a first effort in this field and there have been a variety of improvements and criticisms since then. It would probably be better to focus on what are the range of temperature reconstructions that people are considering today. In particular, MBH shouldn't be the only temperature plot on this page. I realize that there are links to other reconstructions on this page and associated discussion, but by only showing the MBH plot, it gives the implied impression that this is the only important view. I have in mind something like a nicer version of figure 1 from this page [9]. Dragons flight 21:43, Feb 11, 2005 (UTC)

(William M. Connolley 21:56, 11 Feb 2005 (UTC)) I'm quite happy to de-emphasise the "hockey stick", and thoroughly agree with your "mentality" comment above. I wanted a pic showing all (or most) of the recons but couldn't find one; is the pic you point to usable in wiki? It would be nice if it was.

[edit] Moberg et al

(William M. Connolley 21:58, 11 Feb 2005 (UTC)) And if anyone wants my take on Moberg, which I've just read, try: http://mustelid.blogspot.com/2005/02/moberg-et-al-highly-variable-northern.html.

[edit] personal attacks

Lumidek, the discussion is already heated enough and it is completely unneccessary to make the situation worse by personal attacking others. Stopping this would be helpful, thanks. -- mkrohn 13:56, 11 Feb 2005 (UTC) (see Wikipedia:Wikiquette and in particular Assume good faith).

I don't think that the discussion is as intense (and heated) as what I would find appropriate. What the "hockey team" has done is very serious. By the way: This particular article is mostly flawed, it will need a serious reconstruction. I am assuming good faith of Wikipedians, but I am not forced to assume good faith of criminals and the people who don't follow the rules of scientific integrity. --Lumidek 15:04, 11 Feb 2005 (UTC)
Lumidek, are you aware of the fact that M&M have been wrong (in painfully obvious ways, e.g. the radians/degrees debacle) before? And funny enough, whenever one mistake is pointed out, they use a different method to come to the same conclusion... I would not put much trust into their claimed results before the paper has been discussed for some time. Certainly not enough to accuse Mann et al of being "criminals". --Stephan Schulz 03:01, 13 Feb 2005 (UTC)
You are aware that Mann et al. seem to be indulging in the same method to defend their hockey stick? Whenever one error is pointed out they show that the hockey stick can be salvaged if you do something slightly different. And I believe that MM have been fairly consistent with their argument about the data-mining nature of the MBH algorithm (red noise in --> hockey stick out) and demonstrating that MBH's hockey stick is the result of a programming error. At any rate, past errors are not relevant - what is relevant is whether the current work has errors in it. -- John Simon (not registered, just watching from a dispassionate distance)
I am a scientist (and hence read and write a lot of scientific papers), but not a climate scientist (hence much of the specific math is beyond me). However, from what I have read, the older errors in MBH are mostly minor. The McKitrick et al errors, on the other hand, are real whoppers (using the vector norm as an average for temperature (thermodynamic nonsense), using non-absolute temperatures for that (mathematical nonsense), confusing radians and degrees, mistaking correlation and causation in a crass manner, and so on). I used to give them the benefit of the doubt, but after I looked over some of the older McKintrick papers (and commentary) yesterday, I lost all faith in whatever they do. --Stephan Schulz 22:22, 13 Feb 2005 (UTC)
(William M. Connolley 21:18, 13 Feb 2005 (UTC)) MBH haven't accepted any of M&M's points as affecting their results, but some of McK's errors have been too obvious for him to fail to accept. And you're wrong about the red-noise stuff: that wasn't in their earlier paper(s?). "programming error" is wrong BTW - if its an error - MBH don't accept it is - its methodological, not a bug. (Disclaimer: I'm part of http://www.realclimate.org).
Noted. I am also scientifically trained (wouldn't want to claim being a scientist as I am but an economist who happened to do a lot of physics, maths and statistics at grad and undergrad levels) but have been struck by the lack of direct responses to criticism by many participants in the debate. For the most part my comment was reflecting on the passionate (as opposed to dispassionate) nature of much of this malestrom and the playing of the man rather than the ball. I can see how past errors can inform ones view about probabilities, but each idea should be assessed on its own merits. Repeated comments about radians/degrees (which seems to be the preferred soundbite in this area) seem akin to a schoolkid loosing an argument (please note the use of the word akin above before assuming that this is my take on the current imbroglio) and then saying ..."Yeah! Well you can't tie your shoes!" - JS 05:29, 14 Feb 2005 (UTC)
In my experience, getting a Journal paper published takes anything from 9 months (in the most extraordinary cases) to 2.5 years from the day of submisson, with an average of maybe 18 month. Adding in the time for reading and understanding the criticism, and drafting a reply, do not expect anything published before late 2006 - that is, if Mann et all even feel the necessity and find the time to respond formally. In the meantime, various online resources discuss the various McKittrick papers, incuding some comments by Mann (and co-authors). Try [10].
One additional remark: I have ideas plenty. Other people have many more. If I asses each idea equally, I will be swamped just checking on nonsense. I take the presentation, the quality of the source (estimated by looking at previous contributions), and even my own qualification in dealing with it into account when deciding where to spend my time and energy. McKitrick does not do well on either of these scales. --Stephan Schulz 14:38, 14 Feb 2005 (UTC)
(William M. Connolley 10:19, 14 Feb 2005 (UTC)) Errr... you're complaining about a lack of direct response (on the discussions here, or do you mean between the various paper authors?) yet I have directly responded to your points (MBH don't accept M&M's crit; M&M haven't maintained the same crit; "programming error" is wrong) and you have slid away from them. I don't see how schoolkid analogy helps here - if you want to know whats going on, you'll need to look at the details.
In response to your comments I said 'noted' to indicate that you had responded to those characterisations I had made and, although I did not say it, that I would investigate them further while reserving judgement. The comment about lack of direct response was not directed at your response but at my impressions of the general debate (both here and in the various blogs and websites that specialise in this stuff) and would be more appropriately directed to the authors and, more so, cheerleaders. The schoolkid analogy was designed to elucidate my view of a debate where frequent references to past errors are made along with other questionable rhetoric. My view of the debate has been that it is commonly on the level of schoolboy debate - hence the analogy. Don't get your knickers in a twist - if I wanted to have a go at you I'd call you an acerebreal cephalopod. Until then assume that I am a reader of the Midnight Star. -JS 12:31, 14 Feb 2005 (UTC)

[edit] New figure for article

I have created and uploaded the following image.

Image:1000 Year Temperature Comparison.png

Details are included on the image description page. I will let other people decide how to use it in this article. Dragons flight 01:59, Feb 13, 2005 (UTC)

Wow, this looks great, thankt! Would it be doable to make two more plots with 4 resp. 5 functions in each image? I think this would improve readability, as having all 9 functions in one image is very confusing. -- mkrohn 02:19, 13 Feb 2005 (UTC)
Can you make the code public so it can be studied and reproduced? Or, so Marko can make readability adjustments. Perhaps on the Image page have explanations and details, so links can reach such details. (SEWilco 21:06, 14 Feb 2005 (UTC))
The image page already makes it pretty clear what I did. I may release the code (Matlab format) after I have a chance to add comments and clean it up a little. Dragons flight 21:23, Feb 14, 2005 (UTC)

[edit] Translation of jargon

Having read MBH 98 I have found that the statistical jargon used in that paper is very different from the statistical jargon to which I am used. Nonetheless, as part of my education, I am trying to translate their methodology into jargon I can understand. This section is, thus, a request for education but also intended as the precursor to a potential technical appendix to the article that might explain the methods used by MBH to those from a different statistical background.

This may be an inapprorpiate place to have this discussion - if so please redirect me (and this section) to the appropriate place, otherwise, answer away.

To illustrate some of my problems they commonly use the term "reconstructive skill" when referring to what I would more commonly call "goodness of fit" statistics e.g. r2. They refer to singular value decompositions (SVD) in forming estimates and discuss each step of the matrix algebra involved, but I would commonly refer merely to the OLS estimate (β=(X'X)-1(X'Y)) rather than bothering with details of the matrix algebra and computation methods that are used to arrive at that solution. That is, SVD is a mathematical technique that can be used to arrive at the OLS estimate (these days it is relegated to a particularly low level of any statistical programing language because matrix inverse functions are readily available along with even higher level functions which directly generate the OLS estimate).

That given, my current understanding of the technique used in MBH 98 is:

1. Instrumental temperature recordings from around the globe are analysed using PCA to generate a set of principal temerature components which they identify with various global temperature trends, e.g. the Northern Hemisphere average, the El Nino deviation and a North Atlantic deviation.

2. They regress each proxy they have individually against these PCs to obtain a Least Squares estimate of the way each individual proxy responds to global temperature fluctuations.

The basis of their method from here on begins to confuse me somewhat...

3. They collect the coefficients from each proxy regression (which is a mapping from temperature PC to proxy) as a collection of new variables and regress the temperature PCs against these coefficients. This yields a way to go from fitted proxy to temperature PC. I find this step confusing because it seems to go back in the opposite direction to step 2 and I am not clear about its purpose.

4. Regardless, step 3 then provides a way to estimate temperature PCs from the proxy data and thus reconstruct temperature during earlier periods when instrumental data is unavailable. (But because I am fuzzy about step 3 this is currently an article of faith for me rather than an expression of full comprehension).

I have some questions that I would appreciate any explanation for as a way of clarifying and expanding on the steps enumerated above:

1. Is this just a complicated way of describing instrumental variables regressions (otherwise known as two-stage least squares)? What labels should then be applied to the various data series in this context? Are the proxies the instruments?

2. Why don't they just regress the proxy series over the 'training' period on the PC temperature series? They have 112 proxies (although there seems to be some discussion about the exact figure) which can be used as explanatory variables for the first (and other) temperature PC which is about 150 (?) annual observations, to obtain a way of predicting the first temperature PC over the full extent of their proxy data.

3. How are non-temperature factors in the proxies dealt with? (Is that the reason for step 3?) For example, there is a non-stationary CO2 factor that undoubtedly affects the tree ring proxies. One will end up wth a spurious or, alternatively, meaningless regression if one uses I(1) RHS variables to explain an I(0) or I(1) LHS variable (unless appropriate correction is made for the integration e.g. first differencing among other techniques)

- JS 10:10, 15 Feb 2005 (UTC)

(William M. Connolley 22:11, 16 Feb 2005 (UTC)) I've never read the full details, sadly. I think you've missed something: firstly that not all the proxies go all the way back, so there is a "stepwise" technique that uses all that are available in different timeframes; secondly (I think) that PCA/SVD is used to reduce large numbers of proxies down to a few EOFs, when the proxies are dense in certain regions.
I know I have missed something - hence the request for clarification and contribution from those who know more. At the moment my questions about the method are at the first order level. The stepwise technique is, to my mind, a second order element of the technique that I have not turned my mind to yet - undoubtedly important but not fully ripe for consideration until the foundation is in place. I am confident about their description of step 1 and what it means. They use PCAs to generate the global temperature trend(s) (a small number of series which they identify with, presumably, known temperature patterns) from numerous regional instrumental data series (if they use proxies in this step then that would be news to me and it is not clear from their description). They also use PCAs to reduce some of their proxy sets to lower dimension by extracting the principal trends before using them in steps 2 and 3.
- JS 22:27, 16 Feb 2005 (UTC)
JS,
When I last studied MBH 98, I came to the conclusion that there simply weren't enough precise details to be able to reproduce what they did. You can certainly get the gist of what they are doing, and in fact that may have been enough to convince Nature and the reviewers that their approach was reasonable. However, it has always struck me as scientifically bad form that no where in the paper or the supplmental materials did they provide a detailed elaboration of the methodology and justification for each step.
Personally, I think this oversight has a lot to do with the McKitrick & McIntyre debacle. Because MBH weren't more detailed and precise, M&M had to make a variety of assumptions about what MBH had done in their reconstruction. As a result, M&M's "audit" of MBH actually ended up using different methodology than MBH in several key places. Naturally, Mann replies that M&M didn't do things "correctly". M&M replies "but you never said anywhere that you were doing THAT", and a big brouhaha ensues. In general, I believe this has left M&M's audit irrevocably flawed, but at the same time I have considerable sympathy for M&M. They were trying to reconstruct MBH's analysis from published accounts that seem to have been fundementally inadequate for accomplishing that job. MBH deserve to be soundly criticized not providing adequate documentation, but the results they reported do seem to have been reasonable given what was understood at the time and what has subsequently been revealed about their actual methodology. (Note that reasonable is not neccesarily that same thing as being correct. One really has to evaluate their work in the context of subsequent and related work before judging what is correct. But I do not believe that MBH was intending in anyway to be malicious, as some commentators have implied. I should probably also say that I don't have a lot of sympathy for M&M when it comes to the way they have continued to play up their "audit" of MBH and the associated methodological disagreements.)
Anyway, if you really want to understand what is going on in all of this climate reconstruction business, I would suggest you look at a variety of other papers in the field. [11] has some useful references in this regard. I haven't studied most of them, but I would certainly hope that many of them provide more detailed descriptions of the methodology. IF you really want to dig more deeply into what MBH in particular was doing, you probably ought to read M&M and the ensuing methodological arguments with Mann. An archive of those arguments are provided here [12] and a variety of other discussions appear at RealCimate. Sifting through those arguments can be deeply unpleasant, but as far as I am aware, some of the technical details specific to MBH have only ever been reported as a result of those arguments.
So far, I haven't really answered your questions though. In order to really give you a thorough answer of what MBH are doing, I would have to study all the materials again, and I don't really have that kind of time. However, in outline form, what MBH did was take instrumental records from many different spatial locations and compare those to proxy data at "nearby" spatial locations. The purpose of the temperature PCs was to first determine what fraction of the variability in local temperature changes could be related to global vs. local climate change. The proxies in a given regions were then used to make PCs for that region which were (more or less) compared to local temperature changes, and (at least in theory) an overall understanding of the contributions of local and global temperature change to those proxies was extracted. Then by weighting the proxies based on how strongly they recorded global temperature changes one could (hopefully) combine them in a way which was an adequate reflection of long-term temperature change, with some error bars based both on the statistics associated with the number of available records and the fraction of variation that was likely to be local. [My apologies if any of this description is factually inaccurate. I am working from memory right now.]
To my understanding, no one has ever attempted to specifically correct for CO2 variations as a contributor to changes in tree development. However, there are good reasons for believing that most trees growing outside the tropics are water-limited in their growth not CO2 limited.
Dragons flight 15:45, Feb 17, 2005 (UTC)
Much obliged. I have made an edit to the method description in the article based on the broadest understanding of their method (and, indeed, my understanding of the method used by this class of studies) which is, I hope, uncontroversial. (Controversy seems to surround the validity of any of their methodological steps.) We'll see how long it takes me to digest the references you have provided (or whether I get a severe case of indigestion and need to take an emetic).
JS 20:41, 17 Feb 2005 (UTC)
(William M. Connolley 21:08, 17 Feb 2005 (UTC)) A couple of comments... firstly, thanks for your edit on the page. Second, if you just want to understand one of the reconstructions, and aren't too concerned as to which, then I think the recent Moberg one is fairly simple and fairly well documented. Since I wrote http://www.realclimate.org/index.php?p=122 I certainly think I understand it. Thirdly, you may find some more recent Mann et al papers helpful in understanding MBH98 (or more recent Mann work) (though you may not like the post titles...): http://www.realclimate.org/index.php?p=98 and http://www.realclimate.org/index.php?p=10 (the last provides a link to the Rutherford et al preprint).
The following is a quote from the Rutherford preprint "After roughly 1960, the trends in the MXD data deviate from those of the co-located instrumental gridbox SAT data for reasons that are not yet understood (Briffa et al., 1998b; 2003; Vaganov et al., 1999). To circumvent this complication, we use only the pre-1960 instrumental record for calibration/cross-validation of this dataset in the CFR experiments." I am concerned that their procedure doesn't so much circumvent the problem as brush it under the carpet. I will provide my thinking below and I ask for comments. At the moment this is just a small detail that jumped out at me and I make no claims that it means anything about anything - I am just asking for explanation of the methodological justification from someone who knows more.
My thinking: They have observed that for some of their sample the MXD tree ring density data correlate with local temperature measurements, but that after 1960 they don't. Thus, there is a factor other than temperature that is affecting the tree ring densities (or the relationship is highly non-linear or both). It strikes me as more logical to assume that this factor affects the data throughout their sample rather than just after 1960 (which they implicitly do by dropping the data). A consequence of this is that they may suffer from an ommitted variables bias in their pre-1960 calculations - at worst they could have estimated a merely coincidental relationship. Dropping data from a period when their hypothesis does not fit does not circumvent the problem, as suggested above, it just brushes it under the carpet. For those who do not follow this I'll offer an imperfect analogy (as all analogies are): I observe on Monday through Friday that there are many cars on the road in the CBD during daylight hours. I hypothesise that the sunlight causes cars. However, on Saturday and Sunday I notice that there are fewer cars on the road in the CBD and about as many as there are at night. It would be improper scientific practice to discard the Saturday and Sunday observations merely because they do not fit my hypothesis. I should, instead, replace or refine my hypothesis that sunlight causes cars in the CBD. Comments?
JS 00:58, 18 Feb 2005 (UTC)
Tree ring width followed temperature from 1880-1960 relatively convincingly and then they diverge dramatically. Briffa et al. 2003 would agree with you that some other variable in the environment must also be important and varying after 1960. They suggest (as do earlier Briffa papers) that the confouding factor is changes in UV flux associated with ozone depletion at high latitudes. To support this they offer some limited evidence that the divergence is most pronounced near the Arctic circle. Because we really only have a UV and ozone measurements for a short time period, it is hard to know if this is the correct interpretation. However, it would give a logical reason for assumming that this confounding factor is only a recent problem, given that ozone depleting air pollution is only a recent problem. So I agree, it is a issue that gets swept under the rug, but they at least offer a plausible reason for doing so.
Dragons flight 01:56, Feb 18, 2005 (UTC)

(William M. Connolley 21:18, 19 Feb 2005 (UTC)) You may find http://www.realclimate.org/index.php?p=121 useful for tracking what is done. And it would probably be a good place to ask questions if needed. Don't be offended by the title :-)

Thanks for the link. I'd already had a read of that post and digested some of it. At the moment my questions are predominantly methodological rather than data-related and the current controversy, as set out in the article, is mostly framed as a data issue (although I suspect that these can overlap significantly - faulty methodology can allow faulty data to distort the results). I have a bit of investigation still to do and may not be in a position to post anything substantive there or ask sufficiently informed questions for a while. The article comments may be closed by the time I work it all out (if hell hasn't frozen over first - or would it be more apropos to say Europe given the current topic?). Nonetheless, I am currently contemplating the possibility that there is an omitted variables bias in these reconstructions coupled with the possibility that, because temperature and CO2 have both trended strongly over the past century, there may be a problem of spurious regressions (see the top of p.363 in particular). It strikes me that such musings cannot be dealt with adequately in a blog and would, if even only partially well founded, ultimately require a correpsondence with the authors - such correspondence couldn't really be commenced until I knew exactly what I was talking about. Regardless, with any luck, Wikipedia should have a nice tight article on it all at the end of it.

JS 01:54, 20 Feb 2005 (UTC)

[edit] Links

Let's leave "blog" links (e.g. realclimate.org) and links that require subscription fees to access them (e.g. the nature article) out of wikipedia, shall we?--JonGwynne 01:45, 17 Feb 2005 (UTC)

I (mostly) disagree. realclimate.org features reasonably well-written and mostly stable articles. It is not a classic blog where one guy dumps his random musings daily until he gets bored. I do not see how the ability of users to discuss articles on realclimate.org devalues it as a source. In fact, given than Mann et al are writing on the web site makes it even a primary source for the discussion. Why don't you want it in? The link to the Nature article is indeed not very useful for most people. I suggest to move it to to the links section and qualifying it with (requires subscription). --Stephan Schulz 01:57, 17 Feb 2005 (UTC)
You mean: well-written... in your opinion. I'm not saying you aren't entitled to your opinion or that I necessarily disagree with you, but Wikipedia isn't an editorial page, it is an encyclopedia. A blog is a blog - it is a place for people to indulge in chit-chat and is not, therefore, a suitable source for authoritative statements in an encyclopedia. The problem, as I see it, with citing even statements made by famous names in a blog is twofold. First, we have no way of knowing if the person in question really wrote the statement (there is no concept of security or validation in these blogs) - in other words, someone claiming to be Mann could write something and post it. Also, Michael Mann isn't a terribly uncommon name, so someone else with that name could be writing. Second, we have no way of knowing what weight to attribute to the statement. Did the person in question write it seriously after much consideration and then hand it off to others for review and revision before finally publishing it? Or did he come home after several pints at the local pub with his mates and dash off a drunken screed? Or was it somewhere in between? We have no way of knowing.--JonGwynne 13:37, 17 Feb 2005 (UTC)
By that reason (a blog is a blog), a journal is a journal, and hence Nature is the same thing as the National Enquirer, and we can get rid of all the unreliable scientific stuff in one go. The meaning of blog has shifted very fast. Nowadays, anything with articles which the readers can discuss is called a blog, including things like Slashdot that were around for a long time before the term was even coined. Thus, we have to look at a (so-called) blog as at any other source. Doing so in this case, I feel certain that the Michael Mann on realclimate is the same Associate Professor primarily responsible for the hockey stick reconstruction. Looking at the articles, I find that they are written with reasonable care, and are useful as a source for the ongoing discussion. Yes, this is my opinion, but so is everything else in live beyond pure mathematics. I don't believe in Pink Unicornism, and thus I allow my opinion to influence my actions. --Stephan Schulz 23:49, 17 Feb 2005 (UTC)
To the best of my knowledge, articles printed in the National Enquirer aren't subject to peer-review as are submissions to Nature. So, comparing the two isn't really a useful exercise. Your personal certainty of the pedigree of certain blog articles isn't really relevant here, is it? You might be right, an article might be written by the Michael E. Mann, but then again, it may not and we'd have no way of knowing, would we? You are right that there is a lot of opinion and assumption in life... let's not add any more than we really have to. What do you think?--JonGwynne 23:58, 18 Feb 2005 (UTC)
(William M. Connolley 11:39, 17 Feb 2005 (UTC)) The Nature link is very useful to those who have a subscription. As for blogs, its probably best to use them with caution and judge them on their content. AFAIK, the RC Moberg post is the only decent source on the web for a discussion of the Moberg paper (other than mine, which RC obsoletes). If the Nature commentary was freely available, or Moberg had a page explaining his work, I would use that rather than RC.
To WMC: If you want to include the Nature link, then put it down in the "External Links" section with a note that says "for Nature subscribers only". It isn't really fair to non-subscribers to use it is a primary reference. Don't you agree? (Ooops, I see that Stephan had almost exactly the same suggestion. I was reading from the bottom-up so I didn't see his statements until after I had written mine. See? Stephan can be reasonable and discuss things. I suggest you take a page from his book. ) --JonGwynne 13:37, 17 Feb 2005 (UTC)
(William M. Connolley 13:47, 17 Feb 2005 (UTC)) The Nature link *is* the primary reference - how could it not be? It takes up very little space, so there is no obvious resaon to remove it. If you follow it, but don't have a subscription, you get enough info to look it up (volume, page etc) in a paper version in your local library.
It doesn't matter how much space it takes up. Subscription-only links have no place here. Stephan agrees with me - and that should tell you something. If you want to add it to the "External Links" section with an appropriate disclaimer, that's one thing. But if you want to mention the article in the main section, then find a freely-accessible link to it.--JonGwynne 15:24, 17 Feb 2005 (UTC)
(William M. Connolley 15:31, 17 Feb 2005 (UTC)) If you are implying that there is a *policy* against subs-only links, then please quote/link it. In this case, however, the link itself is useful even if you have no subs, because it tells you the volume # etc - as I said above. I certainly take Stephans opinion seriously, but he is not as settled as you are implying, so I will await his further comments.
As I said before, I would prefer to have subscription-only links clearly marked - if only for the personal feeling of disappointment I had when I clicked on the link and found no access to the article. Wether it is inline or separate is not that important to me - I can't think of a really elegant solution. That the link should go somewhere is clear - this is the primary reference, after all. --Stephan Schulz 23:33, 17 Feb 2005 (UTC)


I completely agree with William here. For one there is to my knowledge no policy or rule against external subscription-only links. Wikipedia talk:External_links has some discussion about this, though the discussion was mostly about news related links, where it is easier to get a "free" alternative.
Not showing subscription-only links would be absurd, as links to books also require buying the book and thus would have to be removed. The rule should be, that we always give the best possible reference. Of course if a free alternative of similar quality exist we should link to that.
We can discuss about labeling subscription-only links in order to save the reader a click. Unfortunately I see no technical support for adding such labels, thus we should go on with the usual practice. For further discussion about the topic of labeling subscription-only external links Wikipedia talk:External_links probably is making more sense.
best regards -- mkrohn 17:07, 17 Feb 2005 (UTC)

(William M. Connolley 21:21, 17 Feb 2005 (UTC)) Thanks Marco. I've made a comment at the Wikipedia_talk:External_links#External_links_to_subscription_services page you found, to see if anyone else has opinions.

[edit] Deceptive name of article

The name of the article is inherely deceptive. It describes a proxy record as though it were an actual record. I tried to correct this, but WMC won't tolerate any view other than his own - regardless of the truth of it. The article remains hopelessly POV until it is accurately named.--JonGwynne 21:51, 20 Feb 2005 (UTC)

(William M. Connolley 21:57, 20 Feb 2005 (UTC)) Attempting to push your POV by renaming the article is unacceptable, and great waste of everyones time (including yours). You should not rename a page without discussing it first and gaining a consensus to move it. At the moment, I rather doubt you'll get it.
What POV? It is a fact that the temperature record of the past 1000 years is a reconstruction. It isn't an actual record. Your attempts to cover up this fact are astonishing. Yes or no William: Is the record of the past 1000 years a reconstruction? --JonGwynne 22:00, 20 Feb 2005 (UTC)
(William M. Connolley 22:02, 20 Feb 2005 (UTC)) Isn't it about time you answered the RFA against you?
I still haven't decided if it is worthy of my comment. Your other complaints against me have been so completely lacking in merit and supporting fact that it might well be a waste of my time to comment on this new one. I may change my mind though. Now, isn't it time you answered my question? I'll ask again: Yes or no William: Is the record of the past 1000 years a reconstruction?--JonGwynne 22:14, 20 Feb 2005 (UTC)
(William M. Connolley 22:35, 20 Feb 2005 (UTC)) I think you should go off and answer your RFA and stop treating wikipedia with disrespect. The answer to your Q is: your page move was an attempt to insert your POV into the article name. Next you'll be trying to move CO2 to "CO2 - increase is only 0.01% of total atmos" and then complaining when people say its a silly name.
You didn't answer my question. Let's try again: Yes or no William: Is the record of the past 1000 years a reconstruction?--JonGwynne 22:39, 20 Feb 2005 (UTC)
hint: All you need to do to answer the question is write "yes" or "no".--JonGwynne 22:39, 20 Feb 2005 (UTC)
(William M. Connolley 22:44, 20 Feb 2005 (UTC)) I've answered your question. Now go answer your RFA.
No, you haven't answered the question. I asked you if the record of the past 1000 years is a reconstruction. You have not answered that question yet. Actually, to be fair, it is a rhetorical question. We both know the answer is "yes". Of course the record of the last 1000 years is a reconstruction because there are no actual records going back that far. So, the real question is why did you revert the name of this article back to its original and deceptive state? Oh yeah, because you're a narrow-minded, zealot who can't tolerate view which oppose your own.--JonGwynne 23:15, 20 Feb 2005 (UTC)


[edit] Changing the name of the article

It was rude of Jon to rename the article without any discussion, but even so, the name and focus of the article is a point that may be worth discussion. The name Jon proposed, "Reconstruction of temperature record for past 1000 years", strikes me as exceedingly cumbersome. Something like "Reconstructed temperature for the past 1000 years" would accomplish much the same purpose while being only slightly longer than the current title. However, since the article is pretty clear that it isn't talking about direct measurements, I am not really convinced that quibbling over the difference between a "record" and a "reconstruction" is all that important. But, just to offer an observation, the current page might nearly as well be called "temperature reconstruction controversy", since that is almost the entirety of its current focus.

However, I would like to offer a more general suggestion for feedback from this community. How about dropping the "1000 years" part and just calling it "Temperature reconstructions" or something similar? There is nothing particularly magical about 1000 years after all, and there are at least 4 annually resolved temperature reconstuctions (of the type currently discussed in the article) that go back farther than 1000 AD. If that was decided to be desirable, it would probably need to be part of a broader rewrite to add information on longer time scales. Some brief comments about changes during the ice ages and over geological time scales could be useful for perspective.

Anyway, just a suggestion, and one that obviously requires some feedback before any further action is taken. Dragons flight 00:52, Feb 21, 2005 (UTC)


I didn't mean to be rude. The reason I unilaterally changed it is because the problem was so obvious and the solution seemed a simple one.

Do you notice that you imply that everybody else working on the article is either stupid (for not recognizing the obvious problem and the simple solution), lazy (for recognizing it, but not acting), or part of a giant conspiracy? That is rude. Something as major as a wholesale renaming of a page (especially one with a lot of controversial editing going on) should never be done without a discussion.--Stephan Schulz 13:09, 21 Feb 2005 (UTC)

I was willing to do all the work to edit all the articles that referenced it, but WMC interrupted me halfway through and still hasn't explained why. I take your point about trying to keep the name from becoming cumbersome though. However, there are certain words that have to all be in the title for it to be accurate. In no particular order:
  • Temperature
  • Record
  • Reconstruction
Further, I think there should be some mention of the time frame or maybe just a generic "Historical" would do. What do you think?
How about "Historical Temperature Record Reconstruction"? Your idea of using the word "controversy" in the title is interesting, but I doubt William would ever allow it. --JonGwynne 01:03, 21 Feb 2005 (UTC)
I'm not sure I see the need to use both "record" and "reconstruction", but generally, I'd view "historical temperature record reconstruction" as a very reasonable title. I'm also slightly biased against "historical" because as I said it might be nice to have a few comments about longer term (i.e. pre-historical) climate change for perspective, but unless there is a ground swell of support for including such a perspective, I would be willing to waive that objection. Other people's opinions? Dragons flight 03:47, Feb 21, 2005 (UTC)
(William M. Connolley 09:42, 21 Feb 2005 (UTC)) At the moment there is a (sensible) separation between temperature records from the satellite/balloon record; the historical temperature record; and the proxy record - the last being the one we're talking about. The most problematic bit of the name is "1000 y" as DF has pointed out. "Reconstruction" isn't such a great word though, "proxy" is better. All temperature records are reconstructions (well all are proxies too, though that doesn't mean much). "Historical" is not good, since historical temperature record exists.

[edit] Quantitative vs qualitative

Noticing the recent edit war and vaguely remembering previous edit war(s) I think there is a lot of confusion and aggro created by these two words. When I first read the article I found the use of the words noticeable. There seems to be an implicit sense that quantitative is somehow better than qualitative and this is reinforced with each repetition of these words. I think the impression is subtle but, nonetheless, real. However, I think that their continued use is making a distinction that is not helpful and only creates controversy to no real gain for the article. I have three main points about these two words:

1) Numbers can lie just as well as words can - quantitative is no better than qualitative in terms of objectivity.

2) The 'quantitiative' reconstruction of Moberg et al. doesn't conform to the general slow trend down followed by sharp upturn (I would think a W (sort of) would be a better description of it).

3) The 'qualitative' reconstructions mentioned are actually quite quantitative. Grape harvest times are very quantitiative; records of harbour freezing are also quantitiative; so is the physical extent of farming (e.g. Greenland) which isn't mentioned. If my great-great-great uncle Harry recorded in his diary that "It was cold today", that would be qualitative. If he recorded that winter-crop harvests were low because of unseasonable weather you are starting to stray to quantitative and if he actually recorded crop yields then you are completely quantitative.

I think the actual distinction that is suggested is how comprehensive and representative the data are. But that is a different issue.

Thus, 'I do not think it means what you think it means'.

- JS 02:48, 21 Feb 2005 (UTC)

I agree. The quantitative / qualitative, especially in the opening bit, seems problematic. As you say, this is especially true in terms of quantitative reconstructions, like Moberg, that seems to be agreeing more with what is referred to in the article as the "qualitative" picture of climate change during the last millenia. Though I still think there is a meaningful distinction to be made between records that tell you whether it is hot or cold in a given place and records that (hopefully) tell you something meaningful about the numerical temperature. Perhaps this belongs in a different spot? I would also note that even quantitative records may only provide qualitative information about temperature if there is no practical way to convert the data to temperature measurements.
Dragons flight 03:18, Feb 21, 2005 (UTC)

I was hoping for some more responses, particularly from WMC given that he introduced it all way back when. However, absent further responses, I will look to doing some editing shortly. Silence will be taken as agreement.

- JS 03:03, 23 Feb 2005 (UTC)

Normally, that might be ok. But you do know that Wikipedia was partially down (and still does not do watchlists for me) due to a power failure? I'd wait until things are back to normal. --Stephan Schulz 16:14, 23 Feb 2005 (UTC)
WILCO - JS 20:27, 23 Feb 2005 (UTC)

[edit] Recent Edits

In attempting the minor change to remove the quantitative vs qualitative split discussed in the section above I found that more significant changes were needed to make the article flow properly. I have recast the split as between those showing minimal prior variability and those showing more variability. I have also removed a lot of stuff that gives this issue its heat, but which I judged to be non-central. That is, I have attempted to keep the article tightly focused on the temperature record and removed many comments related to AGW - reducing it to saying that these reconstructions have implications for that debate.

I didn't do much to the second half of the article because I ran out of steam - these sections are still a bit of a hodge-podge. Also, if this recasting of the article sticks, there needs to be a bit of work putting correct links in and fleshing a few things out (e.g. references to those grape harvest papers). Some more cross-referencing to other Wikipedia articles might be in order because I deleted a fair few of those references in trying to keep the article tightly focused.

As a general request, could people not do a wholesale revert but re-edit sections or just revert sections? I think that the previous article needed some work. I've started the process but it is not finished. However, reasonable minds can disagree on this.

- JS 22:28, 26 Feb 2005 (UTC)

(William M. Connolley 22:47, 26 Feb 2005 (UTC)) I really wish you hadn't done that. You've lost a major distinction that the previous version had, which is the distinction between the history-type stuff (LIA/MWP; frost fairs etc etc) and what the quantative recons show; and you have, I think, invented an inaccurate distinction between the various quantiatve recons.
I felt that the previous distinction was confusing and misleading. I do not claim that the current distinction is perfect and there is certainly work to be done on the explanation of regional estimates. I have just a stub for those at the moment. As argued above, the grape harvest ones etc. are no less quantitative than the qualitative ones - but they are regional rather than global. I would think that the distinction that everyone argues about really is how variable the previous climate was. I think that is a valid and important distinction to highlight. I welcome edits to improve this but think that the previous distinction was not right - a regional/global distinction certainly, a distinction based on the degree of variability (which is what leads to all the arguments about whether current warming is unprecedented) certianly, quantitative/qualitative - I don't think that is the most important or most accurate. - JS 00:54, 27 Feb 2005 (UTC)
The problem with the present beginning is that it is focused on a current climate dispute. A distinction similar to the previous one is better for explaining types of records, based upon the methods and tools for producing the records. I think the article should begin with a focus on the end results: temperature records. Then explain the types and methods of records. Various interpretation and analysis can follow. Much of the present variability distinctions should be in a section which compares various records ("this is what is similar and different in the above"), with yet other sections oriented toward interest in certain characteristics ("range of variation is of interest"). (SEWilco 09:26, 27 Feb 2005 (UTC))
That seems like a reasonable comment. On reflection it is probably too focussed on current issues. I think an article starting with the methods and leading to the results might work but I objected to the quantitative/qualitative split (for reasons mentioned above). Nonetheless, a lot of the reason this work is interesting and relevant (and subject to controversy) is very much the question of how large is natural variability. This will not change even when the current controversy dies down. Thus, I think that the range of variability identified is a significant element of what these records bring to the scientific table and should be included in the article. I presume your edits are already in train. - JS 11:03, 27 Feb 2005 (UTC)

[edit] Subject of article

Some ambiguity exists in this article. The subject should be defined clearly. General study of past temperature probably belongs in Historical temperature record. Repetition in this article can be reduced with references to the more general article.

What is the subject of this article?

  • MBH study with a range of 1000 years
  • Recent temperature record (Why 1000 years? Anything significant happen 1200 or 12000 years ago?)
  • Detailed temperature record
  • Climate variation
  • Historical temperature record

(SEWilco 18:48, 27 Feb 2005 (UTC))

(William M. Connolley 19:35, 27 Feb 2005 (UTC)) Hmmm... there are problems with all this. When I created this page, it was 1000 years because that was the longest multi-proxy record. When I created HTR, I really meant *instrumental* temperature record. Probably, there should be:
  • Temperature record - all of it, with sub pages:
    • Satellite/balloon record - last 25/50 years - satellite temperature record
    • Instrumental record - mostly, last 150 years; some discussion of early instrumental (back to 1750 ish). Contents: whats on HTR, up to section "Proxies: tree rings, ice cores: the last 1000 years".
    • Multi-proxy records - about reconstructions of up to the last 2000 years. This current page. Should focus on the various reconstructions, ideally describe how they are done, limiatations, etc.
    • Longer term records: ice cores (800 kyr); ocean cores (Myr but vaguer); other stuff I don't know about...
As to the name... most recons (e.g. the recent Moberg; or von S) still only go back 1000 yr, so the name could stay for now I think.
Moberg goes back to 1 AD.
(William M. Connolley 20:53, 27 Feb 2005 (UTC)) Oops you're right, I was thinking of your graph.
3 other of the temperature comparisons in the plot extend before 1000 AD. I would strongly favor abandoning the 1000 year part of the name. This has already been in discussion above. If we change the name of the HTR to Instrumental, as you suggest, it would remove the principal objection to adding historical to the name of this page. Perhaps something like "Historical Proxy Temperature Records" would fit. I'm not convinced we have found the right name for this page yet, but dropping the 1000 years part is something that I think needs to happen. I would be happy to donate a new figure that shows the full range of existing reconstructions, if there is a suitable page to put it on. Dragons flight 20:21, Feb 27, 2005 (UTC)
(William M. Connolley 20:53, 27 Feb 2005 (UTC)) OK, now you've pointed out Moberg, I agree with the 1000. I don't like "historical" though... because to me that means the Frost-fairs type stuff. And... if we call it proxy TR, then the Frost fairs stuff won't belong. OTOH that stuff could fit into the MWP/LIA pages perhaps. How about "Millenial temperature record"?
Few will understand that, and it is kind on meaningless. Maybe Past Temperature Record"? --Stephan Schulz 01:24, 28 Feb 2005 (UTC)
(William M. Connolley 09:41, 28 Feb 2005 (UTC)) But Past TR doesn't distinguish it from any of the others! Some indication of timescale would be useful.
Why do we need the "record" part? Much of it is not recorded. Can we systematically name the articles "Global Temperature during the last X years" and start the article with a description of the different methods?--Stephan Schulz 22:24, 28 Feb 2005 (UTC)
(William M. Connolley 23:11, 28 Feb 2005 (UTC)) I wouldn't put in "global" - it wouldn't fit, e.g., Moberg (and many others) which are NH only. "Temperature during the last X years"? Possible, but not very update-safe (as "past 1000 years" shows). Could "Temperature during past millenia" do? That implies "a few", which fits 1kyr or 2. Ideally the title should be proof against extension of the record back to 3 kyr. Or we could just live with that when it happens and pick "Temperature of the last 2000 years"?
WMC, I think we have a semantic disagreement with "historical" and "proxy". Perhaps it is just my background, but I tend to view "historical" as everything occuring since the rise of written histories, ie. 6000 years or so. Which I think you would agree is a reasonable time frame for the article. Similarly, I count as "proxies" everything from which we estimate temperatures without the benefit of a thermometer, which to my mind includes frost fairs, agricultural records, frozen rivers, and all the qualitative stuff in addition to the tree rings and more directly quantifiable stuff. So apparently we have different preferences for interpreting the same phrases, even though I think we both have a similar image of what we want the article to be about. For the record, I'm not wild about "millenial" since that just conjures up the 1000 years again for me. Since we are changing the name of the article, I would like to include "indirect", "proxy", "reconstruction", or some other term that indicates that these are not direct thermometry measurements. Dragons flight 14:42, Feb 28, 2005 (UTC)
(William M. Connolley 16:32, 28 Feb 2005 (UTC)) OK, we do indeed have a semantic problem, as yet with no satisfactory solution.
Perhaps the confusion is because there is a continuum of proxies, at one end of which is a simple timeline of variations in one isotope proxy within a single core, at the other end are newspaper reports of when the Thames froze over. The first is an uninterrupted measure of a physical variation, the latter are vague and spotty reports of long events around 0°C. In between are proxies such as tree rings, which can be measured precisely and assembled in long records but there is some ambiguity as to the meaning of the data and several reasons for variations. Also less ambiguous than Thames ice news reports are long grape frost records. (SEWilco 22:26, 28 Feb 2005 (UTC))
(William M. Connolley 23:11, 28 Feb 2005 (UTC)) To me proxy has a more limited meaning, and excludes Frost Fairs. But if it means other things to other people, then perhaps we could avoid it in the page title.
If people agree on this then... HTR needs mv to instrumental TR; new overall page TR needs creation; and some content moves need to occur. *If* people agree here, then we could post notes on those pages *prior* to doing any major alteration.
(William M. Connolley 16:32, 28 Feb 2005 (UTC)) No-one has disagreed with the basic proposal above (though we still have a problem with the 1-2 millenia period name). So I'll put notes on the HTR page.
100 years misses the start of the recent rise. 1000 years lands in Medieval Optimum. 5000 misses Holocene Optimum. Can we agree that "the last glaciation" is the oldest time to consider for current temperatures? The current temperatures seem to begin at the end of the deglaciation, around the Younger Dryas. The deglaciation period has things of interest such as temp change flowing from south to north hemisphere, but there isn't enough ice for such dramatic activity now. The instrumented record based on european thermometer technology is rather well defined. The period between YD and the thermometer is not as well defined, but too large to ignore. What other distinctions are in that period? (SEWilco 22:26, 28 Feb 2005 (UTC))
(William M. Connolley 23:11, 28 Feb 2005 (UTC)) I don't think they should be *designed* to fit various time intervals, for the reasons you give. The split by type-of-record is better based: instrumental (globally to 1850 odd; sporadically further); "calibrated proxy" back 2000y ish; longer term (ice/ocean cores; misc).
What is your definition of "calibrated"? Is this good enough: "At the time the oceans formed, the Earth's temperature was between 0°C and 100°C". (Sorry, I don't have a source handy for whether the oceans formed.) — SEWilco 21:28, 1 Mar 2005 (UTC)
Now, now SEWilco, don't forget that the boiling and freezing point can change as a function of salinity and atmospheric pressure so one can only say that it was only approximately between 0-100°C when the oceans formed.  :-) Dragons flight 21:38, Mar 1, 2005 (UTC)

[edit] No one has objected

(William M. Connolley 23:14, 28 Feb 2005 (UTC)) OK. No one has objected to my basic proposal above (I think). I plan to:

  • Create a main "temperature record" page (only following SS's comment above, perhaps it should be called "past temperature"... not sure. In fact I prefer TR to PT)
  • Move historical temperature record to instrumental temperature record

I'll do this all tomorrow sometime, unless someone objects here first, and/or I realise I can't decide what to call the main TR page.

(William M. Connolley 22:36, 1 Mar 2005 (UTC)) I have moved historical temperature record to instrumental temperature record, and heavily edited the text there. Cut text is to the new temperature record page, for now.

[edit] 2000 year plot for whenever

Since people are discussing reorganization of the temperature record pages, I went ahead and created a 2000 year version of the temperature reconstruction comparison plot. Image:2000_Year_Temperature_Comparison.png

(William M. Connolley 22:05, 5 Mar 2005 (UTC)) How about, just for the moment, moving the page to ...of the past 2000 years? And swapping your new plot in. BTW, I realised that there is a formalism for page moves if we want to use it, which is Wikipedia:Requested moves.

[edit] Removing the "corrected" graph

(William M. Connolley 13:01, 4 Apr 2005 (UTC)) I removed entirely the "corrected" graph. This is the t-rec page, not the mbh vs m&m page. Also, M&M's "reconstruction" *isn't* a reconstruction - they say so themselves. Its also almost without a doubt wrong, as evidenced by its disagreement with all the other versions. So I don't see the point in having it.

[edit] image caption

IMHO the caption should be kept simple. This means that we do not need to mention all details there, this is what the article is for. In this case it is clear anyway that the graph was reconstructed (see the text above the diagram: "Reconstructed Temperature") and furthermore the wording "according to" indicates that these are not temperature measurements. -- mkrohn 00:15, 23 Apr 2005 (UTC)

I agree with you up to the point where facts are obscured. I don't see the problem with mentioning the fact that the vast majority of the graph doesn't represent actual temperatures but rather a theory as to what temperatures might have been based on various proxy data. The caption is already quite a long one, so a couple of extra words shouldn't push it over the edge, wouldn't you agree?--JonGwynne 00:20, 23 Apr 2005 (UTC)
Jon, most of the addition in "the majority of which have been indirectly reconstructed from various proxies" is redudant. "reconstruction" is already mentioned and how the reconstruction takes place ("from various proxies") should not be part of the caption, but is explained in the article. -- mkrohn 00:27, 23 Apr 2005 (UTC)
Of course it has to be mentioned in the caption. Otherwise, there is the implication that this is an actual temperature record rather than a reconstructed one. That it is mentioned in the title is irrelevant, it has to be mentioned every time temperature record is mentioned. Personally, I think this thing is a bit dodgy anyway, I mean it is bad enough that they're mixing all sorts of proxies of various reliability into the same record along with actual instrument readings towards the end. But that's a subject for another time.--JonGwynne 00:44, 23 Apr 2005 (UTC)
We should assume that no one will take five different temperatures for the same year as "actual temperature records". Thus chances that someone mixes actual / reconstructed temperatures are rather small, in particular since the caption points out that the black graph is "instrumental record".
It is very common to adapt the words to the situation, e.g., using "temperature" when we mean "reconstructed temperature". Of course this can only be done if there is no ambiguity. And by the way: "temperature" is always a reconstruction process, e.g., you measure a thermal expansion of some fluid, i.e., some length scale.
The dodgy stuff is called "statistics" and this is serious science :-) Of course statistics (and often the interpretation) are very difficult. Nevertheless this should not be a reason to outright dismiss the results.

"How about this?" (the last edit from Jon). I would clearly agree with the edit, if the text within the picture does not clearly states the same thing. The addition is obviously redundant, but it does not harm either. Perhaps it is better for those who do not carefully read the graph. -- mkrohn 00:49, 23 Apr 2005 (UTC)

[edit] Briffa "omission"

SEWilco added:

There is an undocumented omission in IPCC graphs of post-1960 values for Briffa MXD, which would appear as a precipitious drop to the 1980s. [13]

In my opinion, this is somewhere between misleading and wrong. For the first thing, I don't really think this is an IPCC issue per se, given that Briffa and colleagues have been telling people that the tree ring density series past 1960 is unreliable since at least Briffa et al. 1998. They noted that the MXD record diverges from temperature over recent decades, especially in high northern latitudes. In Briffa et al. 2001 they show that different predictive schemes based on MXD diverge after 1960, i.e. that the inherent uncertainty is large during the recent period. They contrast this against the period 1880-1960 where they argue that different predictive schemes give far more consistent results (i.e. that for some reason the inherent uncertainty was less in the earlier part of the record).

Subsequent papers (e.g. Briffa et al. 2004) have argued that this divergence between temperature and tree ring density at high Northern latitude is related to ozone depletion at high latitudes, which is affecting tree growth through enhanced UV flux and confounding their temperature interpretation. Hence, in their view, this only affects the recent record where man-made substances have been causing ozone depletion. Other authors (Vaganov et al. 1999), argue that the divergence is related to changes in precipitation pattern after 1960, in which case it could be a more generally confounding factor.

Whether or not these arguments are correct is obviously beyond the role of us as encyclopedists to decide (and I am not trying to neccesarily advocate Briffa's conclusions). However, if people believe these details are important then they need to be described accurately and with both sides represented. In particular, it should be pointed out that Briffa et al. wanted to truncate the record significantly before the IPCC TAR was created and this has little to do with the IPCC (except maybe that they should have mentioned Briffa et al.'s reasoning). For that matter, this issue is fairly well-known and documented within the climate reconstruction community and shouldn't be regarded as some great surprise or sleight of hand, unlike the description offered in the linked blog.

Also, it is probably worth noting that no published articles (to my knowledge) take the declining MXD trend as a serious sign of declining temperatures, since colocated thermometry measurements show warming. Hence it is understandable that the IPCC might want to avoid showing the post-1960 data when talking about recent climate change, or when contrasting against other reconstructions, so as not to mislead the viewer into thinking that the recent part of Briffa's MXD record should be regarded as serious evidence of cooling. However, these discrepancies would naturally bear on how reliable (or not) tree growth may be as an indicator of climate change and certainly are appropriate to that discussion.

I'll let other people decide what, if anything, should be written about this issue in the article.

Dragons flight 23:55, May 9, 2005 (UTC)

References:

  • K. R. BRIFFA, F. H. SCHWEINGRUBER, P. D. JONES, T. J. OSBORN, S. G. SHIYATOV & E. A. VAGANOV (1998). "Reduced sensitivity of recent tree-growth to temperature at high northern latitudes". Nature 391: 678-682. DOI:10.1038/35596. 
  • K. R. BRIFFA, T. J. OSBORN, F. H. SCHWEINGRUBER, I. C. HARRIS, P. D. JONES, S. G. SHIYATOV & E. A. VAGANOV (2001). "Low frequency temperature variations from a northern hemisphere tree ring density network". JGR 106 (D3): 2929-2941. 
  • K. R. Briffa, T. J. Osborn and F. H. Schweingruber (2004). "Large-scale temperature inferences from tree rings: a review". Global and Planetary Change 40 (1-2): 11-26. DOI:10.1016/S0921-8181(03)00095-X. 
  • Vaganov E.A.; Hughes M.K.; Kirdyanov A.V.; Schweingruber F.H.; Silkin P.P. (1999). "Influence of snowfall and melt timing on tree growth in subarctic Eurasia". Nature 400 (6740): 149-151. 

PS. If you have access to it, the Briffa 2004 reference is good summary of the issue, showing both the clearly divergent trends and giving Briffa et al.'s explanation for it.

"this has little to do with the IPCC (except maybe that they should have mentioned Briffa et al.'s reasoning" Yes, indeed they should. Should they also have mentioned the uncertainties in tree behavior? I mentioned the IPCC as a significant point in the chain of data presentation, not as the origin of the truncation. I was aware of those papers, but thanks for mentioning them for other contributors. (SEWilco 04:19, 10 May 2005 (UTC))


[edit] William's absolute statement

WMC tried to replace the statement

"An important aspect to the difference between the two classes of reconstructions is whether the warmth during the past century is within the bounds of previous natural variability or not."

with

"In all cases, the warmth during the past century is outside the bounds of previous natural variability"

If you're going to make an absolute pronouncement like that, you'd best have some support for it. Nothing less than a published journal article with support for that statement including agreement from several noted skeptics will do. In addition, such a statement requires quantifiable and universally accepted definitions of both the degrees of warming and natural variability (neither of which seem to exist).

Until you provide such support, we'll go back to the qualified version. --JonGwynne 19:31, 25 Jun 2005 (UTC)

Who is this "we" you talk of? As a cover for your POV pushing, its transparent. The support for the statement is, of course, to simply look at the figure just next to it. William M. Connolley 20:00, 25 Jun 2005 (UTC).
Ah, I see you have once again failed to support your claims. Isn't this a violation of the injunction against you? Do you dispute that there is still disagreement as to the amount of warming and the extent of natural variability? Since that is the case, wouldn't it be absurd to try to make an absolute statement that all current warming during the past century is outside the limits of natural variability? Of course it would. But it doesn't stop you. Why not? --JonGwynne 08:11, 26 Jun 2005 (UTC)
"all cases" and "previous" cover too broad a range yet the article is focused on only a few centuries. Are you claiming the statement is true on time scales of thousands and millions of years? (SEWilco 03:39, 26 Jun 2005 (UTC))
Maybe over the timescale of the article, past 1000 years, no? Vsmith 04:03, 26 Jun 2005 (UTC)
Then you or WMC should have no trouble providing a reference to a peer-reviewed paper stating this. I'll take the failure to do so as an indication of inability rather than disinclination, shall I? --JonGwynne 08:13, 26 Jun 2005 (UTC)
So in an article on Supreme Court of the United States it would be proper to have: :"In all cases, people who have made decisions in the past have worn black." (SEWilco 14:27, 26 Jun 2005 (UTC))

JG is just trolling. Happily, he's just been banned for 3 months, so we can all ignore him. SEW, your comment is... opaque. If you want to take on the mantle of JG, do let us know. William M. Connolley 19:48, 26 Jun 2005 (UTC).

I would argue for having both statements there rather than replacing the first with the latter. They deal with different things - the original is a statement about what is relevant while the latter is an answer to the implicit question in the first. I also think the diagram is not as conclusive as William argues - the black line of the instrumental record certainly rises above the other lines - but the appropriate comparison is between the levels of the reconstructions. In that respect, the variability in the past century is equal to (to a near enough approximation) the previous variability - look at the red (Moberg) and light green (Esper - particularly on the longer graph that Dragon's Flight prepared) lines for example. The MWP peak is about the same as the level of the reconstruction today - that does not meet the standard of 'all' and 'outside'. JS 28 June 2005 05:12 (UTC)

I don't see how we can have both statements - they are inconsistent. Or rather, the version I really intended to write - replacing "warmth" with "temperature rise" - is. So, is the current version better? Also, I've replaced "two classes", which I rather dislike, with vary between, which expresses the idea of a spectrum rather better, I think. William M. Connolley 28 June 2005 09:20 (UTC).
OK JS

[edit] Snowfall/isotope.

Hmm well, DF edited to:

as is the amount of snowfall over many glacial sites. Further, the isotopic composition of snow, corals, and stalactites can also record temperature changes.

Snowfall *is* related to T, but its not a very good proxy and isn't really used much, AFAIK. If anything, I rather suspect that the deep timescales for Vostok etc are based on the reverse: T used to calibrate acc rate. Anyway, *all* the wiki graphs of ice cores T show the O18 T proxy; none show the snowfall proxy; so why give prominence to snowfall? William M. Connolley 08:57:41, 2005-07-24 (UTC).

[edit] 213.122.123.31 / 213.122.105.117 / 213.122.182.235 / ...

Anon 213.122.123.31 (etc) has been waging an odd campaign over at Ross McKitrick and Talk:Michael Mann (scientist) which has now (unfortunately) spilled onto this page, where she has pasted in stuff from the McKitrick page. I don't think this is appropriate. This page is about the T history; not the disputes. It mentions them, but shouldn't fill up with all the tedious detail. William M. Connolley 08:35, 19 October 2005 (UTC).

I find very odd that you find OK to mention an error made by mckitrick which was in an unrelated article but find a error made by Mann in the hockey stick article a tedious detail. So I removed the refenrence to error of mckitrick.--MichaelSirks 12:38, 19 October 2005 (UTC)
They were both mentioned - William out the details, since they are better in the dtr article. Guettarda 13:28, 19 October 2005 (UTC)
First the error of Mckitrick is in an unrelated article, so it is not relevant here. You are creating the impression that you want say because he made error in in unralted article you can't trust them. Second the error( the cosine one) which Mann made is now accepted by every one. (even William? If you don't agree say so.) It is not corrected in corrigendum. And furthermore has been replicated Wahl en Annan. William made big deal of error of McKitrick but is unwilling to mention the known error in Manns study. So I remove reference.--MichaelSirks 13:52, 19 October 2005 (UTC)

I've never seen a ref to the Mann cosine error. Our anon (was it you) never ref'd it. If you have a ref, do put it up. Somewhere relevant. William M. Connolley 14:52, 19 October 2005 (UTC).

You never asked this question in any of the five comments you made at Talk:Michael_Mann_(scientist)#Cosine, and I assumed you already knew everything about the global warming debate. You could try the article in the September 30th, 2004 issue of Science by Hans von Storch et al. Or the Tim Lambert blog you seem so happy to use as a source (various comments by Lambert himself in http://timlambert.org/2005/06/barton). Or other likely suspects.18:20, 19 October 2005 (UTC)
September 30, 2004 issue of Science? Not surprised William didn't read that one - the folks over at sciencemag.org don't seem to be aware of that issue either. How about picking a real issue? Guettarda 18:35, 19 October 2005 (UTC)
I copied the date from this article - perhaps you would like to change it here. A search at Science turns up "Reconstructing Past Climate from Noisy Data Hans von Storch, Eduardo Zorita, Julie M. Jones, Yegor Dimitriev, Fidel González-Rouco, and Simon F. B. Tett Science 22 October 2004; 306: 679-682; published online 30 September 2004 [DOI: 10.1126/science.1096109] (in Reports)" 21:22, 19 October 2005 (UTC)
Over at MM, you were rather coy about proposing any text, so there was nothing to comment on. G has pointed out a problem with the Science. I point out that the TL blog you point to doesn't contain the word "cosine". So what exactly are you referring to? And I've removed some of your comment: do please try to keep this polite and relevant. William M. Connolley 20:33, 19 October 2005 (UTC).
Confirmed. Moreover, manual scanning of the blog entry and all the comments also turned out nothing remotely related. --Stephan Schulz 20:50, 19 October 2005 (UTC)
You can read about it at http://www.climateaudit.org/?p=275. Do you William think Mann is correct to use cos(a) instead of (cos(a))^(1/2)? If you think it is not correct shouldn't he admit it and do his calculations again? Could you please anwser my questions.--MichaelSirks 20:44, 19 October 2005 (UTC)
"cosine" appears 12 times in the blog thread. You might want to go direct to Comment 186.20:54, 19 October 2005 (UTC)
Blog thread? Who cares about blogs - I thought we were talking about a mythical midweek edition of Science. Guettarda 21:03, 19 October 2005 (UTC)
See reply above. The problem was this article which you do not sem to have spotted. It seems 30 September was when it was published online, 22 October on paper. 21:22, 19 October 2005 (UTC)
So it was alright to make a link to tim lambert's Blog when it was about the error of McKitrick, but wrong when it is about Mann. But Please anwser my questions William!!!--MichaelSirks 21:39, 19 October 2005 (UTC)

MS, its hard having a conversation when you don't know who is writing what. Are you the same as anon 213...? Also, please cut the offensive jokes (I have). Now, I can't find cosine in the post you refer to, and neither can the "search" function, so please can you past here the bit you're talking about. As to Mann's error: if he was wrong (and he might be) its a small effect. M&M's error (confusing radians and degrees) completely scrambles the data. William M. Connolley 08:40, 20 October 2005 (UTC).

You do not seem to be talking about MichaelSirks's link to a climateaudit tread. The anon's link comes to page five of Tim Lambert thread on Barton v. Mann. Go to page four [14] to find comment 186 from Tim Lambert, which starts with a long quote from the "Note on weighting observations" at [15], and ends with Tim Lambert's own words: So that to weight by area, the input to PCA has to be weighted by the square root of area. I retract my sugestion that von Storch might have been mistaken — he found an error in MBH98, though he does not seem to think that it was important. I am not sure that dismissing errors with "a small effect" is really the point in the scientific method: the willingness to acknowledge and correct methodological errors may be more important. --Audiovideo 09:06, 20 October 2005 (UTC)
Ah, thank you, thats rather more helpful than referring us to somewhere in a 5-page thread. I've also looked at the Science article (don't bother look at the paper, its in the online additional material). Its a throw-away comment by von S. Its probably an error in MBH98, though I haven't verified that. Its very unlikely to be of any significance (for the obvious reasons), UNLIKE M&M's degree/radian error which completely scrambled their dataset. William M. Connolley 10:34, 20 October 2005 (UTC).
M&M didn't make a mistake in degrees and radians I think you mean McKitrick in a not related article made that mistake.
Of course M&M did. But McK and McI don't have a trademark on the M&M label.
And thereby deliberately misleading people who read this talk page. --MichaelSirks 20:40, 20 October 2005 (UTC)
That is the reason why I am amazed that you want to mention it here. You give the impression that you want to suggest that McKitrick doesn't know the differnce between radians and degrees.(thereby suggesting that you can't trust the work of M&M.)
On the latter point, definitely. William M. Connolley 20:15, 20 October 2005 (UTC).
It doesn't surprise me, but now it is in writting.--MichaelSirks 20:40, 20 October 2005 (UTC)
This is not the case, he mistakely assumed that a subroutine used degrees instead of radians. When confronted with his mistake he admitted it and recalculated his work correctly. I fully agree with audiovideo when he says; I am not sure that dismissing errors with "a small effect" is really the point in the scientific method: the willingness to acknowledge and correct methodological errors may be more important. Then you say; "it is very unlikely to be of any signifigance". There is only one way to be certain and that is by doing the calculations correctly. And by the way I am not anon.--MichaelSirks 20:02, 20 October 2005 (UTC)
If you're not 213... then spiffy. Why you're picking up her half of the conversation, I don't know. There is an easy way to tell whether the not-sqrt of the cos makes any difference: have M&M attacked MBH for it and redone the figures? No they haven't. Why not? They claim to have the code all set up. The only explanation is that they *have* redone the calculations and found that the change (as expected) is tiny, but don't want to publish that. Unlike M&M' who completely scrambled their data points with their degrees/radians mistake. William M. Connolley 20:15, 20 October 2005 (UTC).
It is the resposibility of Mann to admit his mistake and do a recalculation. You have very strange ethics. --MichaelSirks 20:40, 20 October 2005 (UTC)
You're trolling. Do come back when you have something to say. William M. Connolley 21:05, 20 October 2005 (UTC).
So you now seem to agree that Mann+ made a cos(latitude) mistake, as McKitrick+ did, even though the mistakes were different. That at least is progress, though given your behaviour I don't really think your opinion counts for much. By the way, it is considered rude to censor other people's talk comments. 22:15, 20 October 2005 (UTC)

[edit] Interesting links

[16] [17]

Especially a correlation with a number of sunspots is interesting. Miraceti 01:49, 11 February 2006 (UTC)


[edit] Open Source Data - Random Data Produces the Same Graph

I have not updated the page itself as I wanted to share it with the community first. David Stockwell has released his version of the "hockey stick graph" created using Mann's proposed algorithm and completely random data. http://landscape.sdsc.edu/~davids/enm/?p=34

I don't think you should update the page. This is just some random blog. Also, do read the text there. Also, you could try looking at the pix on *this* page... William M. Connolley 13:46, 3 March 2006 (UTC)
Reviewed the link. Uncertain why 'random blog' would have anything to do with the quality of the content. Disinterested scientific method calls for repeatable results. The author of the page has presented his algorithm (same as MBH) and published his data. The results are repeatable.
Ah, you've reviewed the pix on this page. Excellent. And you conclude, of course, that just as the page says there are a variety of reconstructions using a variety of different methods all producing the same hockey stick shape. As for the rest: I'm glad you like the quality of random web pages: try http://www.wmconnolley.org.uk/sci/mbh/ instead then. Also, you seem to be taking rather a lot on faith. For example, "the results are repeatable". How do you know this? Have you done it? Do you think its described in enough detail to allow you to reproduce it? William M. Connolley 10:32, 5 March 2006 (UTC)
You appear to be rather defensive concerning the validity of MBH. Can conclude that you have leveraged their data and method to repeat their results and further attempted a random data set to validate the algorithm? Perhaps you are taking a lot on faith yourself and calling the kettle black. I place more value in scientists, economists, and mathematicians who operate with transparency rather than try to hide or secure their methods and data from "adversaries." That some of the Journals involved in relevant publication do not require the archival of related data and methods for ongoing peer review certainly lessens their scientific value.

I notice a complete failure to address my questions... are you just trolling? BTW, please sign your comments with ~~~~ William M. Connolley 19:13, 5 March 2006 (UTC)

[edit] Tree-rings etc...

Is Mann et al. same as Jones & Mann from ftp://ftp.ncdc.noaa.gov/pub/data/paleo/contributions_by_author/jones2004/jonesmannrogfig4c.txt ?

I have verified (by other documentary series and by the model) some low peeks in file 4c "Annual unsmoothed ...", 3rd serie - documentary serie from Europe. But other series in this file differ from this serie significantly.

The tree-rings show not only global temperature, but also overall humidity and solar input to this tree. The less trees stand beside the measured one, the more sunlight is received and rings grow better. I`ve tried to analyse ITRDB database, but the spread is almost 100% - some trees show bigger rings in colder years and vice versa - rather depending on that-tree neighbourhood... Just as a conclusion - any temperature reconstruction based on tree-rings is anything but precise...

And the global temperature increase is not caused by greenhouse gasses (see also global dimming, but rather by continuously decreasing tree coverage. The bare ground is reflecing much more heat than the forest!

Semi 06/04/14.

[edit] Mann's irreproducible results

I know Dr. C. is simply going to revert, but this is my annual attempt to turn this biased article into a neutral one.

You can:

  • help me make this article balanced, by incorporating information which contradicts your pre-conceived POV; or,
  • I will place an {{NPOV}} tag at the top of the article.

You can fool some people, but not all people. Not forever. The Mann et al reconstructions are widely accepted by the climatology community, whereas the criticisms are not - sure, they may be widely accepted but who has been able to reproduce his results? He's being sued to make him show his data and methods.

They might even have to pass a bill in Congress that requires any scientist who accepts U.S. federal funds to share the data on which he bases his findings with other scientists, so they can check whether his work is valid or not.

Among real scientists, a hypothesis is not considered sound if other scientists fail to reproduce the claimed results.

Science fails to advance when:

  • one researcher's work is accepted uncritically because it's "what we want to hear"; or,
  • a researcher's work is ignored because it's "not what we want to hear

I am asking you publicly, Dr. Willian Connolley, to be a real good scientist. --Uncle Ed 15:46, 21 April 2006 (UTC)

(following edit conflict)

Removed the following addition by ED:
has been reconstructed in two significantly different ways. Traditional reconstructions, based on reprocible techniques, show substantial ups and downs (see Medieval Warm Period and Little Ice Age). One modern reconstruction by Michael Mann portrays temperature as steadily declining until sharply rising after 1940.
Mann's results have not been reproduced by other researchers, mostly because he has refused to share his data. It has been claimed that the computer program he used to prepare his famous "Hockey Stick graph" makes even random data appear in the shape of a hockey stick.
as it apeared to be just stuck in without regard to sentence disruption or anything. Ed, are you just trolling WMC here or trying to fool some of the people or what? The info on Mann ... appears later in the article, if you have new sourced info include it there. Vsmith 15:53, 21 April 2006 (UTC)

I fixed the one sentence which was "disrupted". Please explain why the rest of it was reverted. --Uncle Ed 15:56, 21 April 2006 (UTC)

Read what I wrote just above. The Mann dispute is there. Do you have a ref for the refused to share bit? Also note the combative nature of your comments above and your edit summary. And, I am aware that you and WMC have had a long running verbal war game, but the tone of your comments are inappropriate - spoiling for a fight. Vsmith 16:11, 21 April 2006 (UTC)
(after edit conflicts) This article is about the "Temperature record of the past 1000 years" which relates to the work of dozens of scientists. Mann is important to that, but he is not the be all and end all of climate reconstruction. Ed's suggested text makes it appear that the whole issue revolves around Mann and the criticism/acceptance of his work which certainly isn't fair either. I may be swallowing a load of WP:BEANS for saying this, but maybe it is time we think about having a Hockey stick reconstruction controversy (or some such) article rather than conflating the MBH work with the whole of climate reconstruction. Dragons flight 16:06, 21 April 2006 (UTC)

Mann et al. and McKitrick et al. are the only people I know to have addressed the issue. If there are others, by all means add them to the article. It would be a disservice to our readers to present them with only two extremes.

As for the tone, Dr. C. and I get along quite well. I doubt he'll take phrases like "take that!" as meant in any way other then good humor.

If I'm wrong, I'll eat my words. --Uncle Ed 16:31, 21 April 2006 (UTC)

Well, in some sense I already did since I long ago added Image:1000_Year_Temperature_Comparison.png. You might note that of the 10 reconstructions referenced, only 3 include Mann as a coauthor. Dragons flight 16:51, 21 April 2006 (UTC)

Removed again, still no source for the serious charge of refusing to share data. Vsmith 17:18, 21 April 2006 (UTC)

Sigh. Ed, unfortunately, has swallowed the skeptic nonsense whole. So... personalising this around Mann is wrong. As DF has pointed out, and indeed drawn, there are a whole pile of different reconstructions *all of which fit the TAR text*. On to Ed's text:

Traditional reconstructions, based on reprocible techniques, show substantial ups and downs (see Medieval Warm Period and Little Ice Age). One modern reconstruction by Michael Mann portrays temperature as steadily declining until sharply rising after 1940.

First off, I've no idea what he means by "trad recons" (and I strongly suspect he doesn't either). If he means annecdotal evidence from forst fairs, etc, then he should say so. Second, these are not "reproducible" in the sense that different records show (or don't) MWPs and LIAs at different times. Third, the paper is MBH, not M. Fourth, Eds edit [18] was done in such a fit of speed that it doesn't even make sense - a sure sign that he wasn't really thinking. Fifth, Ed of course doesn't know about Wahl and Ammann... I'll add it. William M. Connolley 18:10, 21 April 2006 (UTC)

No time to rebut ALL of your five points, so I'll just pick some low-hanging fruit. I do so know about Wahl and Ammann. M & M comment here. And what's a forst fair? Robin Hood's merry men celebrating? ;-) --Uncle Ed 19:20, 24 April 2006 (UTC)
So if you know about W+A, how can you call the results non-reproducible? William M. Connolley 20:07, 24 April 2006 (UTC)
Low R2 values (see multiple regression). --Uncle Ed 20:15, 24 April 2006 (UTC)

Um, Ed, do you have a clue what you're talking about? You said *non-reproducible*. Are you backing away from that in a cloud of ink?

Nope. Feel free to expound on MBH's data and methods - and on other researchers who have been allowed to see them OR have been able to reproduce his results. You could even add this to the article! --Uncle Ed 21:20, 24 April 2006 (UTC)
Is that "nope" to "do you have a clue" or nope to retreat? So, your argument is... MBH can't be reproduced, even though, err, W+A have reproduced it. Errm... Help me, I'm struggling to understand your "low fruit" William M. Connolley 21:29, 24 April 2006 (UTC)

[edit] NRC report

I took most of the NRC report stuff out, on the grounds that this is very recent stuff and really ought to be allowed to settle a bit before it gets added to the article in any but the most neutral terms. Also, its a rather long report, so could anybody adding refs to it add the actual page/section or somesuch.

So, any chance we my try to hack out some agreeable text on the talk page? Reactions to the report go from the NAS has rendered a near-complete vindication for the work of Mann et al. to they pretty much concede that every criticism of MBH is correct.

So in particular I'd like to see In all cases, the increase in temperature in the 20th century is the largest of any century during the record. not tampered with much - it remains true. The NRC assessment is that the records are less reliable before 1600. So In 2006, a National Academy of Sciences panel concluded that because of substantial uncertainties about the climate before 1600, there exists no sufficient scientific evidence for either of these statements. [19] does not seem reasonable - thats not what they said. They don't seem to say anything specific about probabilities - only that pre-1600 is less confident than post; this is formally just about null, since we all knew that anyway. What matters is just how less certain they are... which is hard to judge. William M. Connolley 18:21, 25 June 2006 (UTC)

I've looked over a small part of the report, and they claim a high level of confidence for the claim that that last few decades of the 20th century are warmer than any time in the last 400 years. They are less certain about the last 1000 years, and have little confidence about the first millenium. That does not mean they disagree with the reconstructions, they just see larger uncertainty for the reconstruction of earlier temperatures. I found Lumidek's edits to be "creative", to say the least. --Stephan Schulz 21:08, 25 June 2006 (UTC)
As a start, the spaghetti graph could remove any study which contains strip-bark samples or Mann's PC1 since the NAR said their use was "not recommended" for temperature reconstructions.—The preceding unsigned comment was added by 213.122.87.91 (talk • contribs) .
I did the first addition and asked for expert elaboration. What came after was a biased interpretation, to my mind, so I 'adjusted' it. I'm new here so am happy to abide by whatever the agreed conclusions are. I would like to say that the summary [20] conclusions (page 4) of most importance to the debate are: - SBO
  • "It can be said with a high level of confidence that global mean surface temperature was higher during the last few decades of the 20th century than during any comparable period during the preceding four centuries. This statement is justified by the consistency of the evidence from a wide variety of geographically diverse proxies." - SBO
  • "Less confidence can be placed in large-scale surface temperature reconstructions for the period from A.D. 900 to 1600. Presently available proxy evidence indicates that temperatures at many, but not all, individual locations were higher during the past 25 years than during any period of comparable length since A.D. 900."
NB, 'less', not 'none' - SBO
I believe that the report is intended as 90% or more vindication of the various proxy data graphs and their conclusions, with 10% of reservations that the data gets less reliable as it gets older, and that this is not always acknowledged in the more obvious headline-grabbing conclusions. - SBO
I also think that the paragraph on page 5 of the summary - "Surface temperature reconstructions for periods prior to the industrial era are only one of multiple lines of evidence supporting the conclusion that climatic warming is occurring in response to human activities, and they are not the primary evidence." deserves stressing. - SBO
That last point may be important in discussion of global warming. But its only significance for this page is to say that this page is less important than it used to be taken to be.

You are misrepresenting their conclusions. They say that the reconstruction after 1600 is, in its qualitative features, reliable, by which they mean 90-95 percent confidence level. The reconstruction of temperatures before 1600, averaged over longer timescales, is "plausible". They choose not to quantify it but they say that they mean something like 2:1 odds. Everything else is "even less confident", which means qualitatively less than a 66% chance. This includes not only the first millenium temperatures but also the detailed annual temperatures before 1600, including the statement that 1998 was the hottest year and the 1990s were the hottest decade in the millenium. "They just don't know whether it is true," they describe their report at the press conference. --Lumidek 13:56, 26 June 2006 (UTC)

I am unsure how I can misrepresent a conclusion when I am quoting it verbatim and providing the link to the source for everyone to confirm the quote. Their specific concerns about the period between AD900 and AD1600 are the precision of the data with respect to annual and decadal variation - which makes claims about 1998 and 1990s between 66% and 90-95% certain. (if the lower limit is 66% and the upper is 90-95% as you claim, it cannot be unquantified and 'about 2:1') That does not invalidate them. It just makes them less well supported and worthy of further investigation. The reservations do not rule out their support for the main conclusion made by Mann et al - that the last 25 years have been the warmest for a millenium. As this has a wider resolution, it is better supported by the data. I again point you to page 4 of the summary. - SBO

The current wording from Lumidek includes the phrase "large uncertainties make it impossible" which I feel is overstating the case considerably. I would like this changed to "uncertainties make it less plausible" which is more in keeping with the vague wording of the report, as well as its intent.--Hoggle 23:38, 26 June 2006 (UTC) (also SBO)

Not "less plausible" (uncertainty can't do that), but "less certain". --Stephan Schulz 06:19, 27 June 2006 (UTC)
fair point, although 'confident' is their wording --Hoggle 19:13, 27 June 2006 (UTC)

To sum up where we are so far: Lumidek wants wording as follows:

In all cases, the increase in temperature in the 20th century was thought to be the largest of any century during the record. This conclusion has now been reinforced by the National Research Council's report to the U.S. Congress for the 17th, 18th, and 19th century but the panel concluded that large uncertainties make it impossible to compare the 20th century with any period before 1600.

I would be happy with:

In all cases, the increase in temperature in the 20th century was thought to be the largest of any century during the record. This conclusion has now been reinforced by the National Research Council's report to the U.S. Congress for the 17th, 18th, and 19th century but the panel concluded that uncertainties make it less confident in comparisons between the 20th century with any period before 1600.

So long as there was a more detailed analysis in the body of the article. William wants something like:

In all cases, the increase in temperature in the 20th century was thought to be the largest of any century during the record. This conclusion has now been reinforced by the National Research Council's report to the U.S. Congress. The basic conclusion of Mann et al. (1998, 1999) was that the late 20th century warmth in the Northern Hemisphere was unprecedented during at least the last 1,000 years. This conclusion has subsequently been supported by an array of evidence... the committee finds it plausible that the Northern Hemisphere was warmer during the last few decades of the 20th century than during any comparable period over the preceding millennium.

Let's achieve a compromise from this point.--Hoggle 19:13, 27 June 2006 (UTC)

Not quite... I disagree with "was thought to be". That refs back to the temperature records, and is describing what is in the records, so should say "is". William M. Connolley 19:44, 27 June 2006 (UTC)

So how about: Introduction

In all cases, the increase in temperature in the 20th century is the largest of any century during the record. This conclusion has now been reinforced by the National Research Council's report to the U.S. Congress. (with citation as supplied)

Body

The basic conclusion of Mann et al. (1998, 1999) was that the late 20th century warmth in the Northern Hemisphere was unprecedented during at least the last 1,000 years. This conclusion has subsequently been supported by an array of evidence. The committee found it plausible that the Northern Hemisphere was warmer during the last few decades of the 20th century than during any comparable period over the preceding millennium. However the panel expressed reservations that uncertainties make it difficult to compare individual years and decades of the 20th century with any similar period prior to around 1600.
The report also confirmed the major points of the criticism by MM: the statistical significance of the conclusions about the climate before 1600 is low; the bristlecone pines are not a good temperature proxy; the data and the software should have been made available; and the principal component analysis was not used properly. (with citation as supplied)

It's a bit wordy, but I think it uses everyone's opinion without contradicting either what is in the report or what has already been proposed. I'll add it and see if anyone joins the debate. --Hoggle 19:18, 29 June 2006 (UTC)

I reverted the last edit because it was an argument, not an agreed wording (but kept the change to preceeding millenium rather than record as he had a point). It seems to me that we should keep the words in the introduction to a minimum. We also need to agree the wording in the middle section which I missed from above. It currently reads:

In 2006, a National Academy of Sciences panel concluded that because of substantial uncertainties about the climate before 1600, there exists no sufficient scientific evidence for either of these statements. [11] For a comparison of the common temperature plots, see [12]. (as per Lumidek)

I would prefer:

In 2006, a National Academy of Sciences panel concluded that the first statement was supportable. However, they cannot support the second part of the statement, as it compares fine detail (years and decades) with data that can only be said with confidence to be accurate at a wider resolution. [11] For a comparison of the common temperature plots, see [12].

I think this reflects the actual report more accurately --Hoggle 00:14, 30 June 2006 (UTC)

The piece removed was not an arguement, it was what was said on pages 3 and 4 of the report:
Reviewing this conclusion, the National Research Council's report to the U.S. Congress [21] stated that not all individual proxy records indicate that the recent warmth is unprecedented, although a larger fraction of geographically diverse sites experienced exceptional warmth during the late 20th century than during any other extended period from A.D. 900 onward. The report said with a high level of confidence that global mean surface temperature was higher during the last few decades of the 20th century than during any comparable period during the preceding four centuries; less confidence can be placed in large-scale surface temperature reconstructions for the period from A.D. 900 to 1600; and very little confidence can be assigned to statements concerning the hemispheric mean or global mean surface temperature prior to about A.D. 900 because of sparse data coverage and because the uncertainties associated with proxy data and the methods used to analyze and combine them are larger than during more recent time periods.
First of all, large-scale quotes may infringe copyright. Secondly, the introduction is not the place for anything other than a brief summary of the conclusions. Thirdly, if you wish to influence the outcome, please register like I did.
As for your argument, the value of individual proxy records is always low. It is only when data over multiple sites is considered that a global or hemispherical average can be obtained. The first part of your quote is not relevant to the preceeding part of the paragraph, which refers to claims by Mann et al from studies using multiple proxy measurements. If you wish to quote a part of the report that sums up the conclusions, how about their own summary:
"In summary, large-scale surface temperature reconstructions are proving to be important tools in our understanding of global climate change. They contribute evidence that allows us to say, with a high level of confidence, that global mean surface temperature was higher during the last few decades of the 20th century than during any comparable period during the preceding four centuries." [[22]]
It may not be the wholehearted support that many people were hoping for, but it's far from the condemnation that Mann's opponents keep trying to twist it into. --Hoggle 16:31, 30 June 2006 (UTC)

I've shifted this discussion to decide the wording of each section, below. This section was getting a bit long. --Hoggle 16:43, 30 June 2006 (UTC)

[edit] National Academy of Sciences report MUST be here

Two posters have tried to hide a report by the National Academy of Science, ordered by the U.S. Congress, and its key conclusions. This study is, so far, the most authoritative study of the very subject of this page.

The study has invalidated the scientific conclusions about 1998 being the hottest year in the millenium, the 1990s being the hottest decade in the millenium, and all other major statements that require scientists to know anything about the weather before 1600.

The report of the NAS as we read is the final, complete, and official version of the report. There won't be any developments, and it is absolutely unacceptable to allow anyone to hide this important document from the readers. I hope that no one will try to hide the report again. This is an unconstructive game. You can't hide it forever. How many days do you need to admit that it is the final version of the report that can be described on Wikipedia? --Lumidek 13:42, 26 June 2006 (UTC)

I disagree with your 1st sentence; I'm not certain of your 2nd. Also I don't agree with your 2nd para. I disagree with the intent of your 3rd: the report is indeed complete; just like any paper published in a journal. What isn't complete is the digesting of it and consideration of what it means. Clearly it has statements appealling to both sides; finding some balanced text to describe it is going to require more work than you've done. I agree that the report must be here; but not with your text William M. Connolley 17:31, 26 June 2006 (UTC)
I agree that the report must be included, and that its conclusions be presented in as unbiased a form as possible. I don't know of any attempts to hide it. The only edits on record are mine (I added it in the first place), yours (which prompted the discussion above) and Mr Connolley's (which was to hold off on interpretation of the report until the wording could be agreed). The study has in no way invalidated the major conclusions about late 20thC warming being uprecedented. It has set out a level of confidence that individual conclusions can be given, and given guidance about the work that would be needed to increase that confidence. If it felt that the conclusions were invalid, it would have said so. I find the characterisation of this discussion process as 'hiding the report' thoroughly disingenuous and disruptive. It is also a lie, since the report has been included since I added it and never removed. Only your personal interpretation (and my correction of it - also personal) has been removed. The consensus description will be added as soon as we achieve it. I am happy with that. - SBO
Dear William, thanks for having clarified your points. I have already digested the key messages of the report, and many people have even read the whole bulk - which does not include me. I don't think it is a task for Wikipedia editors to be re-digesting opinions of NAS. They said what they said, it may look a bit ambiguous, but in principle, it is very clear what they could confirm and what they could not confirm. Your first sentence in which you only say a misleading statement that the "study has in no way invalidated conclusions" etc. shows that it might be nontrivial to negotiate a consensus with you. What I wrote was meant as a draft of the ultimate neutral formulation. I controlled my opinions about the matter tremendously and wrote a proportional summary of their expert opinion. I encourage you to act equally constructively, and only if you have reasons to think that something is inaccurate in my description of their report, or if you think that it does not match the proportion of topics in their reports, edit my comments in a continuous way, the way how Wikipedia works whenever it works well. Your attempts to deny that they have rejected the claims about statistical significance of virtually everything that involves the climate before 1600 - a fact that I wrote in a very diluted way in the article to make particularly you happier - cannot lead anywhere. --Lumidek 21:16, 26 June 2006 (UTC)
I'm new here, so I don't know how to sign my comments properly. I guess I should register so things get easier. The second paragraph is mine, not William's - SBO (other comments signed similarly)
Please sign your posts with ~~~~. Lumidek: yes you're being unusually restrained, which is good. Digesting: you're missing my point, so I'll try again: the NAS report, like any other paper, is a finished object but needs to be placed into context. Youll find I've argued this for both pro- and anti- papers. Ideally, wiki would leave a fair time - a year or more - for scientific stuff to settle down before being included. This is an encyclopedia, not wikinews. However, thats clearly unrealistic for things like this. But I still argue that we should try to leave it for a while. I've tried adding a quote from the report which seems fairier to me. Probably there should be a section for the report; or even a page for it William M. Connolley 07:20, 27 June 2006 (UTC)
Dear William, in your latest edit of the article, you pretended that you were just changing the introduction, but you actually tried to erase some paragraphs from the bulk - about the statement that 1998 was the hottest year which the NRC report labeled as completely uncertain. What you were trying to paint as a "quote" at the beginning was not a quote. You selectively chose words from a sentence of the report - the only sentence that you like in the report - and separated the words by "..." so that the meaning and focus of that sentence was moreover seriously compromised. Please try to be more reasonable. Read the full summary of the report, if not the full report, and check that my version correctly summarizes the summary. If you think it does not, please explain on the talk page what's the inaccuracy, and make a selective improvement. What you're trying to do borders with vandalism. --Lumidek 11:16, 27 June 2006 (UTC)

I know its hard for you to assume good faith, but you could try. I eliminated nothing silently; I quite clearly marked it as a revert. I think The basic conclusion of Mann et al. (1998, 1999) was that the late 20th century warmth in the Northern Hemisphere was unprecedented during at least the last 1,000 years. This conclusion has subsequently been supported by an array of evidence... the committee finds it plausible that the Northern Hemisphere was warmer during the last few decades of the 20th century than during any comparable period over the preceding millennium. is a fairer summary that yours. I don't see anywhere that the report says that large uncertainties make it impossible to compare the 20th century with any period before 1600 - an I notice you don't give a page ref. Nor is In 2006, a National Academy of Sciences panel concluded that because of substantial uncertainties about the climate before 1600, there exists no sufficient scientific evidence for either of these statements. [23] justified by its ref, as I've said before. Ditto for your last para.

Based on past evidence, I don't see much chance of L and I agreeing, so I invite others to comment on this. William M. Connolley 12:23, 27 June 2006 (UTC)

This second discussion point - should the report be included in the article - is, I think, settled. We all think it should be. There is consensus on that and we should discuss the wording of the inclusion above. --Hoggle 19:13, 27 June 2006 (UTC)

[edit] NRC Report - wording of Introduction

Starting point

In all cases, the increase in temperature in the 20th century is the largest of any century during the preceeding millenium. This conclusion has now been reinforced by the National Research Council's report to the U.S. Congress. (with citation).

For legibility I think the structure of the article needs a very short and non-committal introduction, with no comment about what the report says or means, other than the bare fact that they are generally supportive of the preceeding statement. Anything more than that can be included in the body of the article under the appropriate sections. --Hoggle 22:49, 30 June 2006 (UTC)

I agree. We now have this:
In all cases, the increase in temperature in the 20th century is the largest of any century in the record. This conclusion has now been strongly reinforced by the National Research Council's report to the U.S. Congress for 1600 onward. The panel finds it plausible that this also holds for the millennium, but notes that larger uncertainties reduce the confidence in these long-term comparisons.
The first sentence does not seem attributable to the NRC, but rather IPCC [2001]; that is not clear in the article. The second sentence seems like it is saying something important, but it isn't: 1600 was mid LIA. Also, the second sentence seems wrong, because it is talking about a temperature increase, which isn't what the NRC is about. The third sentence just says that it is "plausible" that the temperature (increase) was the largest; that is pretty weak, and seems to mean merely 2-1 odds. I think that the above-quoted part of the article needs reworking.  —Daphne A 11:18, 31 August 2006 (UTC)
Regarding the LIA, this was claimed by the NRC report to be "roughly 1500 to 1850".  —Daphne A 11:49, 31 August 2006 (UTC)

[edit] NRC Report - wording of Minimal Variability section

Starting point

The work of Mann et al., Jones et al., Briffa and others (two citations) forms a major part of the IPCC's conclusion that "the rate and magnitude of global or hemispheric surface 20th century warming is likely to have been the largest of the millennium, with the 1990s and 1998 likely to have been the warmest decade and year" (citation). In 2006, a National Academy of Sciences panel concluded that because of substantial uncertainties about the climate before 1600, there exists no sufficient scientific evidence for either of these statements. (citation) For a comparison of the common temperature plots, see (citation).

AFAIK there exists no sufficient scientific evidence for either of these statements. is Lubos's own invention, not the reports. In fact the report seems to be pretty vague about what it thinks the uncertainties are, pre 1600 William M. Connolley 22:28, 30 June 2006 (UTC)

Modified

because of substantial uncertainties about the climate before 1600, there exists no sufficient scientific evidence for either of these statements.

to read

data was too sparse to fully support the decadal and single year conclusions. They did, however, confirm the status of the more general conclusion that the last 25 years have been the warmest for a millenium. (see below)

which presents, I think, both interpretations of the report more fairly. --Hoggle 14:07, 2 July 2006 (UTC)

[edit] NRC Report - wording of Reconciliation - MBH section

Starting point

In 2006, a panel report of the National Academy of Sciences ordered by the U.S. Congress was published. The basic conclusion of Mann et al. (1998, 1999) was that the late 20th century warmth in the Northern Hemisphere was unprecedented during at least the last 1,000 years. This conclusion has subsequently been supported by an array of evidence. The committee found it plausible that the Northern Hemisphere was warmer during the last few decades of the 20th century than during any comparable period over the preceding millennium. However the panel expressed reservations that uncertainties make it difficult to compare individual years and decades of the 20th century with any similar period prior to around 1600.
The report also confirmed the major points of the criticism by MM: the statistical significance of the conclusions about the climate before 1600 is low; the bristlecone pines are not a good temperature proxy; the data and the software should have been made available; and the principal component analysis was not used properly. (citation)

I'd like to see page cites for those last 4 William M. Connolley 22:29, 30 June 2006 (UTC)

Changed 'similar' to 'similarly short' for clarification of the quality that concerns them. It is only the identification of individual decades and years that they feel is harder to fully support, as the precision of the data before 1600 is too low for a high level of confidence. --Hoggle 14:13, 2 July 2006 (UTC)

[edit] NRC Report - wording of Reconciliation - NRC Report section

I added this section so that the five main conclusions can be either quoted directly or reworded in brief as I have done. I'm not sure if such a large quote would constitute fair use. It would be good if we could keep opinion, interpretation etc to the other sections and leave this without editorial comment. --Hoggle 22:49, 30 June 2006 (UTC)

Given that this is a public report for the senate, I'm fairly certain that even large quotes are ok under fair use. Certainly quoting single paragraphs is unproblematic.--Stephan Schulz 22:53, 30 June 2006 (UTC)
I'll change it to a direct quote --Hoggle 14:14, 2 July 2006 (UTC)

[edit] Wegman Report

I am new here and not particularly familiar with Wikipedia so please forgive me if I am posting something incorrectly. While I am not a paleoclimateist, I do have a foundation in statistics and had been skeptically curious about the methods used in the 1998 IPCC report in the past.

My contribution to the forum was the inclusion in the Criticism section an except and link to a recently released report conducted by independent statisticians (i.e. not related to the pale climate community, nor industry - furthermore conducted pro bono).

As this is likely another step in an interesting discussion I do not consider this to be the final word from the statistical community. The report itself [24] contains the most comprehensive statistical criticism of the reconstructions and are worth linking to in this section. Thank you. ~~~~. D. Salenger

I disagree. The Wegman report looks like a regurgitation of M&M, with very little added and no understanding of climate. The NRC report is far better William M. Connolley 16:45, 17 July 2006 (UTC)
What you meant to say was that "eminent independent statisticians endorsed M&M's statistical criticisms of MBH" but somehow you did not manage to type it 19:27, 17 July 2006 (UTC)
I suspect what he wanted to say was: "Statisticians with no background in climate science, but selected by a politically biased body, claim to confirm criticism of one temperature reconstruction, but fail to address about 15 others showing similar results, and (so far) fail to get their work published in any established scientific journal (or any other peer-reviewed venue)." --Stephan Schulz 19:42, 17 July 2006 (UTC)
It does appear that the Wegman report has simply repeated the original critique of the 1998 Mann et al paper (NB NOT the IPCC report!) by M&M which has some validity in statistics. All of the valid criticisms of the original work have been addressed and corrected where necessary and the original conclusions are fundamentally unchanged. It is futile to keep changing things back and forth every time someone re-states the original arguments. Yes, the 1998 studies had some statistical errors. Yes the US government, who funded the study, are looking at it very closely to see if their money was mis-spent. No, the work has not been invalidated or reduced in importance. No, the political shananigans do not belong on this page except as a sidenote. This page is about the state of paleoclimate research NOW - not just an argument over one paper published 8 years ago that, let's face it, was the first of its kind. As such, it should reflect the emerging consensus that temperatures in the past few decades are unprecedented over the preceeding 1000 or more years. The processes and methodologies have been revised and improved over that time, and the Wegman report merely advises a greater use of statisticians in government-funded paloeclimate research (what else would you expect from a committee representing the interests of statisticians) to avoid making similar mistakes in the future. In a debate over the management of government science programmes, it is appropriate to study the report. In a page discussing scientific findings it only deserves a footnote and reference.
If the anonymous newcomer wishes to add the quote, I trust he will accept a quote from Mann rebutting it, in the interests of balance. --Hoggle 19:55, 17 July 2006 (UTC)
Hoggle, unless I am not using wiki correctly, my name is at the end of my post. William, the NRC report may be 'better' from a general topic view. This report is strictly interested in the statistical methods employed in climate reconstructions - depth versus breadth.
Fair point, missed it. Welcome to the bloodbath Mr Salenger :) --Hoggle 15:29, 18 July 2006 (UTC)
Stephen, I found your quote partially correct - The statisticians do not have a background in climate science. However, we could just as easily say that the climate scientists in question are not recognized experts in statistics nor have they published per reviewed articles in the appropriate statistical journals in which they could demonstrate the validity of their methods).
Finally, your suggestion that the statisticians were selected by a politically biased body is not correct. Only Wegman himself was tasked by Congress. Do you have reason to call his intellectual integrity or statistical expertise into question? Or perhaps that of his colleagues? You are free to argue the merits of the research but this is a low blow and not useful in this type of conversation.
Please continue to read the report. From a statistical perspective it is more a condemnation of the mathematical methods used in these types of reconstructions than solely a condemnation of the IPCC research. 69.255.1.237 22:24, 17 July 2006 (UTC) D. Salenger
Professor Wegman's responses to questions from Representative Stupak can be found here - http://www.uoguelph.ca/~rmckitri/research/StupakResponse.pdf. Interesting also for the display of social networks that involve Dr Mann. He makes it clear that he is not commenting on anthropogenic global warming, merely the fact that the methodology used by Mann is such that it will show a hockey stick whatever data is put in - CynicalSurprise.
How odd then that he says the hockey stick shape must be in the data to start with or the CFR methodology would not pick it up. Are we perhaps reading different reports? William M. Connolley 13:08, 24 March 2007 (UTC)

[edit] Edit summary, 17 July 2006

In order to avoid going into too much detail in the edit summary, I need to explain that the source link WMC complains about ("How about this quote instead, actually sourced to a page rather than lazily the entire report?") was originally added by Lumidek (here), not me. And I thought it was appropriate, not lazy, to link the the first page of the report, since the entire sentence dealt with more than just page 106. --Spiffy sperry 20:05, 17 July 2006 (UTC)

Its still lazy - its a long report; linking to the first page is well nigh useless. And since I'm here, I didn't much appreciate your previous edit summary William M. Connolley 21:08, 17 July 2006 (UTC)
Would you prefer 3 links to 3 different pages, rather than 1 link to the beginning? I don't like the Open Book format at darwin.nap.edu (sep. link for each page), but I can't control that.
And about my previous edit summary ("WMC hid a deletion in his last revert, or reverted to far"), I was going to apologize, but changed my mind. I could come up with 2 explanations for your revert on July 16, which I portrayed in my edit summary.
    1. You reverted 86.17.239.73 to Dragons flight (the most recent version), while at the same time deleting/changing material without explanation in your edit summary ("rv nonsense"). When I see "rv" in the edit summary, I assume there were no other edits other than the revert unless told otherwise, an assumption I'm sure other editors would see is reasonable.
    2. You reverted 86.17.239.73 to William M. Connolley (14 edits prior), without explaining that you were going that far back, which was peculiar since 3 editors managed to revert 4 times without losing useful information. When I see "rv" in the edit summary without a description of what it was reverted to, I assume that it was reverted to the most recent version prior to the offending author(s). If this is the case, then you were calling the addition of a direct quote from the NAS report "nonsense". While we demonstrated that it could be improved, it certainly wasn't nonsense.
--Spiffy sperry 21:49, 17 July 2006 (UTC)

[edit] Prometheus Article

I've added a link to this and the Steve McIntyre quote, as it should prevent people from over-attributing the relevance of the debate to modern climate change.

Not sure why you quote P, when RC said it first... anyway, its oddly positioned. It might be better in the intro to qualify the relevance of all this William M. Connolley 09:05, 30 July 2006 (UTC)

[edit] Biased sampling?

I removed this section:

[edit] Biased sampling

In the paper Reconstruction of past climate using series with red noise, David R. B. Stockwell showed that by using the methodology of dendroclimatology, but using red noise instead of tree ring data, one can reproduce the hockey stick graph.

The steps to construction were as follows: 1. Generate 100 sequences of 2000 random numbers with long term persistent (LTP) stochastic process. 2. Select sequences with a positive correlation with CRU. 3. Average the selected series. The series show a ‘hockey-stick’ pattern due to step 2 - only those random series correlating with temperatures are selected. This step is analogous to only using trees with positive correlation with temperatures. Outside the range of the calibration temperatures the average of the series reverts to the mean value of the random numbers, which in this case is the chosen zero value of the calibration temperatures. This leads to an upward drift in values back through time.[25]

The tree ring data used in dendroclimatology is calibrated using recent data, for which we have measured temperatures with which to compare. But the fact that this recent data is used in calibration means that it is biased, and so should not be used. Thus, the blade of the hockey stick may be a product of the calibration process.

First of all, its nothing to do with biased sampling. And its not a paper. And I've no idea what IAG news is. AFAIK the article itself is obscure, and in particular not cited by either of the recent reports. And its methodology (particularly the formation of the noise) is too brief to assess on its own. So I don't think it belongs William M. Connolley 11:11, 4 September 2006 (UTC)

Original publication is here: http://www.aig.org.au/pdf/AIGNews_Mar06_revised.pdf (SEWilco 04:57, 27 September 2006 (UTC))
Thanks. The next article is by the inimitable Louis Hissink... William M. Connolley 08:27, 27 September 2006 (UTC)


--- Other Sources

The discussion might benefit from a review of independant reconstruction of temperature trends in the recent past. Much of the discussion here concentrates n the Mann paper and its detractors. I recommend addition of a sectiuon on other studies. One example could be the borhole data found at the NOAA site

http://www.ncdc.noaa.gov/paleo/borehole/core.html

Inclussion of the temperature diagram provided there may add to this article. . NOAA says "the diagram below is a global perspective of surface temperature change over the last five centuries, averaged from 837 individual reconstructions. The thick red line represents the mean surface temperature since 1500 relative to the present-day. The shading represents ± one standard error of the mean. Shown in blue for comparision is the global mean surface air temperature (five year running average) derived from instrumental records by P.D. Jones and colleagues at the University of East Anglia"


More on other sources

As part of other sources I find that the AIP article on modern temperature trends revies the historical context much better than this page. I recommend it be added as a reference in othere sources. In particular the AIP article does a better treatment of preliminary opinions and their subsequent development. Or have I missed something, is this a page about Mann and his detractors; if so I recommend that the subject be retitled to reflect that fact.

http://www.aip.org/history/climate/20ctrend.htm

AIP notes "This "hockey stick" graph, prominently featured in the IPCC's 2001 report, immediately became a powerful tool for people who were trying to raise public awareness of global warming — to the regret of some seasoned climate experts who recognized that, like all science at the point of publication, it was preliminary and uncertain...As so often in this story, no single scientific finding could bring conviction by itself, but only in conjunction with many other lines of evidence."

BTW.. I'm new to posting on wikipedia (other sources and more on ather sources). For that reason I'm posting in discussion and not on the article, and request help on how to correct the article itself.

---

A lot of problems with Mann's use of tree ring proxies have been raised. Firstly, he used data from tree rings which did not factor in confounding variables (precipitation and local climate are the ones most commonly mentioned). Secondly, the physical locations of the trees that provided the data sets he used are not verifiable because authors of the studies he drew from refuse to provide locations. Thirdly, because of local temperature variations, tree ring analysis is generally used to show how trees respond to other variables in a situation where the temperature is known - Mann decided to ignore those variables and assume that temperature was the only indication of tree growth. Fourthly, the geographical location (as best it is known) was only for trees in the northern part of the North American continent. - CynicalSurprise

Your name is unpromising; and despite your assertion of not posting to the article, you have. But anyway: this is not the MBH page but the general T rec of the last 1kyr page. Maybe you want the Hockey stick controversy page? It would be a good idea if you provided sources for your various tree ring statements William M. Connolley 12:46, 24 March 2007 (UTC)

[edit] Hockey Stick in Intro

Although there is a redirect there should be something like "...commonly known as the 'hockey stick graph..." or such in the intro. The intro should mention that there are skeptical studies on the graph. Sparkzilla 01:39, 2 November 2006 (UTC)

Which graph are you talking about? Our diagram plots 10 different studies. And if you are referring to Wegman and M&M, they are themselves severely criticised (so where do we cut this off?), and they only deal with one of the 10 reconstructions.--Stephan Schulz 07:48, 2 November 2006 (UTC)
Your comment proves my point. This page redirects from hockey stick graph so it should say which of the graphs is actually the hockey stick graph, and should deal with the controversy surrounding the hockey stick graph. Otherwise please make a separate page dealing with the hockey stick graph because this page does not enlighten the reader.
Also, are you saying that because a critical study is criticised that it should not be mentioned? To me, that is the definition of "controversial" and therefore the controversiality of the hockey stick should be mentioned in the intro.
We have a whole section with several subsections on the criticism. But in the introduction, we should not give undue weight to this one issue. MBH98 is just one of several temperature reconstructions. And the Wegman report, while politically influential, a) is not a peer reviewed publication (i.e. has much less scientific weight) and b) even if correct, does not refute MBH reconstruction, but only claims it is not reliable. This does not belong into the general introduction.--Stephan Schulz 15:59, 2 November 2006 (UTC)
Another point: who exactly do you mean by "our" in the phrase "our diagram"? Do you mean the original researchers or their critics? Surely the critics have a diffeerent idea of what the graph should look like? Or do you classify that as "their" diagram? Does their diagram merit inclusion in this discussion or not? Your claim of ownership shows your bias.Sparkzilla 15:10, 2 November 2006 (UTC)
It does deal with the controversy surrounding the Mann, Bradley, and Hughes reconstruction at length, but that is far from being the only reconstruction of the last 1000 years. "Our diagram" simply refers to the figure currently appearing in Wikipedia, which is a composite of 10 different studies. Please try to avoid reading too much into things. Dragons flight 15:21, 2 November 2006 (UTC)
Please do not avoid the question. Who does the "our" in "our diagram" refer to?Sparkzilla 15:31, 2 November 2006 (UTC)
We, as in wikipedians, i.e. "us". It is Wikipedia's diagram, so it is "our" diagram. If you are really asking who's information is in the figure, then go read about it Image:1000 Year Temperature Comparison.png. Dragons flight 15:45, 2 November 2006 (UTC)
It is not my diagram. You really are in no position to speak for all wikipedians. Sparkzilla 16:24, 2 November 2006 (UTC)
I've never written one word on russian literature, therapeutic cloning, or the Third Reich, but I'm still happy to say that those are our articles on those subjects. Maybe I'll even disagree with what they say (the last two choices are intentionally controversial), but they are still part of a project I care about and feel allied with. I would hope that you would share in that sense of community. Dragons flight 16:44, 2 November 2006 (UTC)
Once again, you have no right to speak for all wikipedians. You are part of an ongoing process, not the end of it.Sparkzilla 00:03, 3 November 2006 (UTC)
I have also noticed that on the Stephen McIntyre page that there is a whole section on "The Hockey Stick Controversy". If this "Temperature record of the past 1000 years" page is the redirect from the "Hockey Stick graph" page then why is this controversy not mentioned here in the same terms? That means mentioning it in the intro and creating a section called "Hockey Stick controversy" As it reads now, you would think there was no controversy at all. Sparkzilla 15:31, 2 November 2006 (UTC)
The term "Hockey Stick" is mentioned in the section "Reconstructions with minimal variability", with a "read below" pointing to "Mann, Bradley and Hughes temperature reconstructions". I've added the term there to make this relation even clearer.--Stephan Schulz 15:55, 2 November 2006 (UTC)

I reverted Sparkzilla's changes [26]. Some of them were fair, but I think pushed too far. This page has a constant tension as to just how much its about the T recon; and how much about the controversy.

I didn't like the demoting of In all cases, the increase in temperature in the 20th century, and the temperature in the late 20th century is the highest in the (reconstructed) record. downwards; and if the section name gets changed to crit of the HS, I don't see why there shouldn't be a "defence of the HS"; but then that would get silly. And The methodolgy used in creating the graph has been called into question, most notably by Stephen McIntyre and Ross McKitrick. in the intro is unbalanced, without mentioning that the other 9/10 graphs haven't been questionned William M. Connolley 16:55, 2 November 2006 (UTC)

Perhaps the other 9/10 graphs have not been questioned yet, but it does still not take away from the situation where the most important graph, the HS, is involved in major controversy.Sparkzilla 00:03, 3 November 2006 (UTC)
Make that "haven't been questionned in peer-reviewed literature". There is a category on "other multiproxy studies" at Climate Audit, and 4/9 of the "haven't been questionned" studies even have their own subcategory. There is indeed some questioning going on, and SM gets told repeatedly to publish on some other studies. --Spiffy sperry 17:27, 2 November 2006 (UTC)
Yeeeesss... I knew that. But I think thats been around for a while. We don't restrict ourselves to peer-reviewed stuff entirely, but. I would have thought that if he were going to publish his crits, he would have done so. Is there any hint there that he is in press or anything? William M. Connolley 17:35, 2 November 2006 (UTC)
William, if there are valid points in what I say they should be worked into the intro, not reverted. Once again, this page is the redirect from HS, so it should mention HS in the intro, and should address the HJS controversy directly, otherwise a separate page should be made that specifically addresses the HS issue.Sparkzilla 00:03, 3 November 2006 (UTC)
That this page is a redirect from HS means nothing at all. There probably should be a separate page for the "issues" William M. Connolley 09:34, 3 November 2006 (UTC)
Well, I found this page in the first place by entering "Hockey stick graph" into the Wikipedia search box. I was somewhat surprised that it was not mentioned in the text. Anyway, I think it is mentioned enough to satisfy future searchers now. Sparkzilla 09:54, 3 November 2006 (UTC)

[edit] "In all cases"

The article says 'In all cases, the increase in temperature in the 20th century, and the temperature in the late 20th century is the highest in the (reconstructed) record.' Is this verifiably true in all cases?Sparkzilla 00:40, 3 November 2006 (UTC)

It is true by inspection. No? William M. Connolley 09:35, 3 November 2006 (UTC)
It is a claim, not the truth - truth is the invention of a liar... --ghw 09:50, 3 November 2006 (UTC)
William, are you sure that EVERY model confirms this, even the models of the skeptics? Happy to leave it as-is if true. Sparkzilla 10:21, 3 November 2006 (UTC)
Gosh, you mean even the secret ones they keep under their beds and don't show anyone? Of course, I inspect them all... But of course, no, the text refers to those plotted on the graph, so you may inspect them yourself William M. Connolley 10:32, 3 November 2006 (UTC)
No need to be facetious. If the text refers to the diagram (and to the ten studies on the chart) that should be made clear -- it wasn't to me, and isn't to the casual reader. I also don't know what you mean by JG? Could you explain? Sparkzilla 10:41, 3 November 2006 (UTC)
I'm not aware of any serious global temperature reconstructions forwarded by the "sceptic" side. The closest I have seen was a 50 year interval sampling of the Sargasso Sea temperature by looking at calcium isotope ratios (and drawn by connecting the dots with straight lines, no error bars given...). As far as I know, our (as in "the one currently in the article") diagram has all reasonable recent studies that have been published in a serious scientific venue. If you are aware of more studies, I'm certain DF will be able to integrate them. --Stephan Schulz 10:48, 3 November 2006 (UTC)
In that case I think it could be better phrased. How about, According to ten major temperature reconstructions published in peer-reviewed journals (see neighboring graph) the increase in temperature in the 20th century, and the temperature in the late 20th century is the highest in the (reconstructed) record. Sorry to be pedantic, but "all" is not really clear enough. Sparkzilla 10:54, 3 November 2006 (UTC)
That's loosing the point that there are no comparable competing studies. --Stephan Schulz 12:01, 3 November 2006 (UTC)
How about... According to all major temperature reconstructions published in peer-reviewed journals (see neighboring graph) the increase in temperature in the 20th century, and the temperature in the late 20th century is the highest in the (reconstructed) record. Is this correct, even when considering SM & RM? Sparkzilla 12:11, 3 November 2006 (UTC)
I think that is a good text. I'd probably loose the "(see neighboring graph)". The connection should be obvious without it. As far as I know, M&M have no temperature reconstruction of their own (and a grand total of one peer-reviewed paper in a rather obscure journal on the topic).--Stephan Schulz 12:31, 3 November 2006 (UTC)
I think that should be three peer-reviewed papers, and one of them was in the same journal (GRL) as 3 of the 10 reconstructions featured here. --Spiffy sperry 14:36, 3 November 2006 (UTC)
Hmm, do you have any pointers? I suspect you talk about Energy and Environment, which at least I don't consider a repectable scientific journal. It is not, for example, recognized by ISI. --Stephan Schulz 15:10, 3 November 2006 (UTC)
He was talking about GPL. Are you sure it is a "rather obscure journal"? Or is it your POV which seems to be coming through strongly? 22:34, 3 November 2006 (UTC)
Sorry if I wasn't clear. Yes, I knew about the Geophysical Research Letters publication (and I consider that a rather obscure journal, compared to e.g. Science and Nature, in which 4 of the studies in the graph are published). I was wondering about the other two Spiffy was referring to. All I could find was a paper in E&E. --Stephan Schulz 22:42, 3 November 2006 (UTC)
In addition to the article in GRL (which has MBH99, by the way), there's two articles in E&E, the orginal one in 2003 and a 2005 update. You can find it all at Climate Audit. --Spiffy sperry 21:10, 4 November 2006 (UTC)
Thanks for clearing that up. I searched on Climate Audit, but found things not easy to find (ptp). And thanks for DF for correcting me about GRL. I may have confused that with some other journal. --Stephan Schulz 08:36, 5 November 2006 (UTC)
As for "Energy and Environment", you will find it in an ISI list at http://scientific.thomson.com/isilinks/journals/e/ 22:39, 3 November 2006 (UTC)
I don't know what that list is but ISI does not index E&E. GRL is the only place indexed by ISI that McIntyre and McKitrick have published together. However, I would not characterize GRL as obscure. Though not the equal of Nature, it is definitely a major publication and one of the top journals specializing in earth science. Dragons flight 22:53, 3 November 2006 (UTC)
So why don't you look at the NAS Panel or the Wegman report? Or just read the statement from MBH theirselves in Nature 442, 627(10 August 2006) admitting the uncertainties and important caveats of their own work? The hypothesis, that there has never been a warmer period in the last 2000 years does not have a significant scientific basis (according to the limitations and uncertainties of the used data and methods).--ghw 07:34, 5 November 2006 (UTC)
None of these changes the truth of the sentence. It only points out that the reliability of the reconstructions goes down for earlier time periods. Is the "2000" a typo? Both the article and the graph discuss just the last 1000 years... --Stephan Schulz 08:36, 5 November 2006 (UTC)

I prefer to keep the pointer to the graph for clarity. Text added. Sparkzilla 13:21, 3 November 2006 (UTC)

[edit] McIntyre Quote

Steve McIntyre has recently been quoted as saying "I'm inclined to agree that, for the most part, the Hockey Stick does not matter to the great issue of the impact of 2xCO2." and this is a point of agreement on both sides

This quote appears to be taken out of context with respect to this page. The quote appears to have undue weight, and makes it appear that SMcIntyre is in agreement about the temperature record. This page is about the temperature record, not the impact of CO2. Could someone help clarify this? Sparkzilla 10:21, 3 November 2006 (UTC)

[edit] Questions about sub-sections

I did a restructuring to improve the flow. No data was removed, just moving text around to make it read better. The restructuring raisies questions about the following sections:

1. Reconciliation of the two approaches I think this should be a sub-section inside the General Techniques section (ie no underline), but I think it needs some clarification. In the section it says the two approaches are historical and statistical, but that is not clear in the preceding sections

2. Uncertainties and limitations Perhaps this should include a wider discussion of unceratintains in models, rather than the focus on one particular instance. Also, I think this should also be a sub-section (no underline) General techniques section.

Looking at the content of these sections again, I wonder if they couldn't be combined into a discussion of the limitations of models. In other words, put the Reconciliation section's text inside the Uncertainties and Limitations section. Another possibility would be to rename the "criticisms of Temperature models" to "Debate about Temperature Models" and put it all in there. Sparkzilla 11:27, 5 November 2006 (UTC)

statistical and historical is itself a historical phrase... much of the past debate has been about the difference between MBH and the "known fact" that there was a global LIA/MWP - that is the "historical" reconstruction approach. For example... this version. The qual/quant distinction seems to have got lost in the present version of the article in favour of different version of the quant record. Note that explains the somewhat orphan Baliunas text William M. Connolley 14:11, 5 November 2006 (UTC)
Quite a big edit where I try to create a good flow in the overall text. I added the qualitative section back in. I also tidied the "debate" timeline. It seems a lot more readable now, although there may be some typos and minor formatting errors. I removed is the the McIntyre quote due to undue weight (see above) and some repetition of NSA and M&M text in the "debate" section. Comments welcome. Sparkzilla 16:20, 5 November 2006 (UTC)
I've added the substance of the quote in the intro, but sourced it to RC instead... its an important piece of information, often forgotten William M. Connolley 17:42, 5 November 2006 (UTC)

[edit] rv TheSeven: why

I reverted TS's changes. Specifically he cut but M&M offered no explanation as to why their analysis also differs from other reconstructions [27]. with no explanation; the fact that M&M differ from all the other recons, not just MBH, is worth noting. Changing "actual results" to "conclusions" doesn't make much sense either: the point is that all the numbers remain unchanged William M. Connolley 09:43, 8 November 2006 (UTC)

The analysis of M&M is solely deconstructive: they criticize others for errors in statistics, etc.. All others have made similar errors. So the statement that you make is not true. (Your last sentence doesn't make sense to me.)  TheSeven 15:03, 8 November 2006 (UTC)
No, M&M offered a "what it would look like with errors corrected". As to my last sentence... oh dear. The "correction" of MBH changed none of the results at all (all it did was clarify the sources). So changing results to conclusions weakens things: just "conclusions" leaves scope for the idea that the results changed somewhat, but not enough to affect the conclusions. Whereas what actually happened was no change at all. You knew that, yes? William M. Connolley 15:22, 8 November 2006 (UTC)
M&M have never suggested a reconstruction. It is true, however, that some of their opponents have claimed that they suggested a reconstruction, and then criticized them for that. So perhaps you have been misled. There is a brief mention of this issue in the Wegman report (p.48). I now understand your point about "results" versus "conclusions".  TheSeven 07:54, 9 November 2006 (UTC)
Au contraire. M&M indeed produced a picture of what they said the curve would look like, with what they said were MBHs errors fixed. See [28] which is the archived copy. Its figure 8 William M. Connolley 09:35, 9 November 2006 (UTC)
M&M did make that "corrected" figure, but they have argued that the underlying MBH is fundementally inadequate for making long-term temperature interpretations. The result is that they do not believe that even the corrected figure should be interpreted as a temperature reconstruction. Hence, from their point of view, they have never published or endorsed any temperature reconstructions, even though they have at various times published plots that certainly look like temperature reconstructions. Dragons flight 17:29, 9 November 2006 (UTC)
I agree with that William M. Connolley 17:38, 9 November 2006 (UTC)

The above issue does not seem to have been reasonably resolved. For now, then, I have put a Noncompliant sticker on the article.  TheSeven 07:18, 18 November 2006 (UTC)

I agree that the very narrow definition of temperature reconstruction biases the viewpoint of the article. This also affects the "In all cases" section above. Sparkzilla 09:09, 18 November 2006 (UTC)
I can't see the non-con tag as being appropriate, so I've removed it William M. Connolley 09:16, 18 November 2006 (UTC)
Just because you have no doubt does not mean there is not a dispute. --Facethefacts 20:57, 19 November 2006 (UTC)
The tags should be added, as appropriate, by those actively involved. Which excludes you William M. Connolley 21:38, 19 November 2006 (UTC)
I come at times, but then your rudeness keeps driving me off. You even copied Image:Ipcc7.1-mann-moberg.png from my Image:IPPC 1990 MBH 1999 Moberg 2005.png without attribution. --Facethefacts 22:19, 19 November 2006 (UTC)
You are a silly person. And of course I didn't copy you - I did it properly William M. Connolley 23:05, 19 November 2006 (UTC)
As I said, I have contributed on the subject before and you are again trying to drive me off with rudeness. Point made. --Facethefacts 23:11, 19 November 2006 (UTC)

[edit] 'Disputed' tag

In reviewing this article I don't see any basis for the disputed tag and thus have removed it. The problems with this article have to do with organization and writing style, not factual accuracy. I'll work on organization over the next few days. Raymond Arritt 23:34, 20 November 2006 (UTC)

I would suggest that it takes (at least) two to dispute, and if you think you can judge on your own whether there is not a dispute then it might be worth reconsidering your position. --Facethefacts 01:52, 21 November 2006 (UTC)
An accuracy dispute in the Wikipedia sense has a more structured meaning than simply saying "I disagree." Please see WP:AD where you will find the following:
The accuracy of an article may be a cause for concern if:
* it contains a lot of unlikely information, without providing references.
* it contains information which is particularly difficult to verify.
* in, for example, a long list, some errors have been found, suggesting that the list as a whole may need further checking.
* it has been written (or edited) by a user who is known to write inaccurately on the topic.
The implication is that a disputant should give his reasons for adding the tag, so that the article can be improved (which is the whole point of the exercise). Which specific parts of the present article are of concern to which specific criteria above? If there are particular sections that are in dispute, then tag those sections. Tagging the whole article implies that the whole article is full of unverified information. Reading the article shows that simply isn't the case -- on the whole, the article is appropriately supported with references.
If you give your specific concerns we may be able to improve the article by dealing with them. But simply hanging a {{disputed}} tag on the article isn't helpful. 05:12, 21 November 2006 (UTC)

The reason for the disputed tag is given in the prior Discussion, and should also be clear from the History. To repeat, the statement "M&M offered no explanation as to why their analysis also differs from other reconstructions" is grossly misleading: M&M have never proposed a reconstruction, they have only criticized other reconstructions. I and others have tried to correct the error, but WMC reinserts it. If that statement were deleted, then the disputed tag could be removed. (I am also concerned about the article's discussion of M&M's GRL paper, but that is not a factual issue, rather NPOV.)  TheSeven 08:33, 21 November 2006 (UTC)

I've rv'd to RA. THe sentence isn't misleading, let alone grossly; I've provided a ref to their *analysis* not reconstruction William M. Connolley 08:35, 21 November 2006 (UTC)
Let's be quite clear what the problem is. WMC regularly introduces apologetics, often with a link to his group blog. A typical example is this edit: [29]. It is a highly controversial issue, in this case because claiming current tempratures are likely to be the highest in the last 1000 years was a significant part of what IPCC TAR put forward and highlighted [30]. Playing it down now may be a change of opinion by some people, but the IPCC has not said so (yet) so it does not belong here. Wikipedia is not for propoganda, and many of WMC's edits are unsuitable. He then decides he is happy with the article and cannot see any reason for dispute. This is an abuse of Wikipedia and very ego-centric. The article certainly is disputed and WMC has a history of making diputed edits making it seem like another of his personal soapboxes. --Facethefacts 08:57, 21 November 2006 (UTC)
Let's be quite clear what the problem is: drive-by edits by GW skeptics who don't know what they are talking about. If you look at the D+A chapter of the TAR, which RA has kindly provided a link for, you'll find nearly 2 pages of summary of D+A; less than 2 lines are about the 1000-y T record. There is no change of opinion; it remains a minor part of D+A William M. Connolley 09:27, 21 November 2006 (UTC)


I have asked ArbCom about WMC's recent actions, which seem very much inappropriate.  TheSeven 09:15, 21 November 2006 (UTC) [You'll be pleased that you've got a response then [31] William M. Connolley 16:24, 21 November 2006 (UTC)]

I agree that the article is misleading and does not have NPOV. To some extent the problem is that the definition of "temperature reconstructions" is too narrow. M&M may not have made an actual reconstruction, but their analysis is an important part of this debate and should be included. The narrow definition of which peer-reviewed journal is important only to academics. The graph should go because the narrow definition of "all major temperature reconstructions published in peer-reviewed journals" is completely misleading. This debate is wider than pure academia.
As an example of how narrow this page is, I had to edit this page to even mention the Hockey Stick (which this page redirects from). The outside world hears "Hockey Stick" and wants to know what it means? If they came here they would think that the debate was minimal, and that the issue had been decided.
To WMC: With all due respect, you have great knowledge about this subject, but you do not own this page. Open discussion of the debate, and a bit of give and take with regard to the general reader, will lead to a better page for all. Thank you. Sparkzilla 09:20, 21 November 2006 (UTC)
Dear S, here we see the problem with the skeptics: they have no real position: its Lawyers science. You think the graph should go, because you think M+Ms reconstruction should be in it. Others however insist that mentioning M+M's analysis being incompatible with everyone else is unacceptable William M. Connolley 09:27, 21 November 2006 (UTC)
No, I said the graph should go because its definition is so narrow as to be misleading. Even if M&M did not make a reconstruction, the graph, by not taking their research into acocount, gives a false impression of the debate. The graph should be removed because it says that there is no debate, when in fact there is. And that is just one example.
You may well have a strong position, but this page is not just about your opinion, your position, nor even about your facts. This page is not the place to attempt to prove who is correct. It is not is not "WMC vs the skeptics". It should be an overview of the issues and the debate around them. Much as some would like this to be a purely scientific discussion, the temperature record of the past 1000 year is actaully a wider issue, and all aspects of the debate should be addressedSparkzilla 10:12, 21 November 2006 (UTC)
The temperature record of the past 1000 years is a purely scientific issue. No amount of debating skill, advertising, or political posturing will change it. The graph does show all serious temperature reconstructions. M&M have raises some issues with one of them, and apparently have not made it clear if they offer an alternative reconstruction or are just generally sceptical about the process. Of course we can (and should) include criticism and the political debate, but without undue weight, and without giving the appearance that they have the same weight than the actual published (peer-reviewed) science.--Stephan Schulz 10:28, 21 November 2006 (UTC)
"The graph does show all serious temperature reconstructions" surely depends on what YOU narrowly define as serious ie. your POV. The graph gives a misleading impression to the reader that everyone who is "serious" is in agreement, when they are not. I came to this page to find out more about the hockey stick and I found very little to let me understand the debate about it, some of which is clearly political.. If you do not include the wider debate, and insist on narrow definitions, then the page has to be classed as inaccurate. Sparkzilla 10:38, 21 November 2006 (UTC)

M&M *have* specifically denied doing a temperature reconstruction, so they don't get included in the graph. They have published an "analysis" which disagreed with all the others, showing a very warm MWP. The graph shos all the reconstructions; saying that its misleading is bizarre. Given the extensive section on the Debate, If you do not include the wider debate and I found very little to let me understand the debate about it is also bizarre. I suspect that what you mean is, "I don't find things to fit my POV emphasised right at the top", but thats another matter William M. Connolley 11:43, 21 November 2006 (UTC)

You still don't seem to get it. The statement "all major temperature reconstructions published in peer-reviewed journals" may be accurate, but it is misleading because it presents a narrow sub-set of analyses. The fact that M&M have not published their own reconstruction is irrelevant -- they dispute the temperature reconstructions in that graph, therefore the graph does not show the full picture. At the very least the graph and accompanying text should be labelled as being in dispute. Sparkzilla 14:36, 21 November 2006 (UTC)
This is very funny: major peer-rev stuff has become, in your mind, a narrow sub-set of analyses. No, they are the mainstream of the scientific view on this topic. YOu're now down to arguing that yes, all the major peer-rev stuff says this, but we should balance it by minor or non-peer-rev? The graph is accurately described. M&M get a mention in the intro, and thats fair enough, they get about as much space as they deserve William M. Connolley 14:44, 21 November 2006 (UTC)
Once again you miss the point. It's not about balance. I dont care if M&M's graph is on their or not. The graph attempts to show that there is consensus on the temperature record when there isn't. It's misleading, and it should be removed. Sparkzilla 17:25, 21 November 2006 (UTC)
You destroy yourself: you suggest that we should have this article *without a graph of the various reconstructions*, just because someone has disputed *one* of the reconstructions? Try to take this seriously William M. Connolley 17:34, 21 November 2006 (UTC)

"Much as some would like this to be a purely scientific discussion, the temperature record of the past 1000 year is actaully a wider issue, and all aspects of the debate should be addressed". I find this amusing - despite the fact that it's an interpretation of scientific data, we need everyone's input, especially those of people who follow their "gut"? Right? Are we talking about GW or creationism? Or maybe the Iraq war? It's so hard to tell - the arguments are all exactly the same... Guettarda 14:17, 21 November 2006 (UTC)

The keyword here is "an interpretation".Sparkzilla 14:36, 21 November 2006 (UTC)
How so? (Being less cryptic is helpful) Guettarda 15:28, 21 November 2006 (UTC)
You said: I find this amusing - despite the fact that it's an interpretation of scientific data. Interpretation = politics = POV. A major issue on this page is how to balance the different interpretations of the data, scientiofic or otherwise. Sparkzilla 17:17, 21 November 2006 (UTC)
"Interpretation = politics = POV"? Wow. So you have just dismissed the entire enterprise of science? Data without interpretation isn't science. Science is about the interpretation of data in accordance with the scientific method. Sure, science isn't without cultural context and all that crap, but it has less than any other means of knowing and it is fundamentally self-correcting. If you are a postmodern relativist who believes that there is no reality beyond what you construct for yourself, I see how you might have a problem with science. But then, I have no idea how you would write any encyclopaedia article if you believe that sort of stuff. Guettarda 19:14, 21 November 2006 (UTC)
That may be science but it is not Wikipedia. We can quote the IPCC's interpretation (though they did not say it was "minor") or Real Climate or Dr William Connolley's later interpretation. But we cannot put it forward as a fact. That is not how Wikipedia works.--Facethefacts 19:57, 21 November 2006 (UTC)
Interesting that you were quite willing to assert that it was of "major" importance despite the fact that IPCC never said so, and now you're criticizing others for saying it's of "minor" importance. You're painting yourself into a corner with regard to your latter point (on how Wikipedia works). Raymond Arritt 20:06, 21 November 2006 (UTC)
OK, I admit the IPCC did not say "major", they just put it in the summary and other documents. But nor did they say "minor". So why not accept my compromise and leave it out of the introduction? --Facethefacts 20:17, 21 November 2006 (UTC)

[edit] D+A

We seem now to be arguing over:

Although temperature reconstructions from proxy data help us understand the character of natural climate variability, they play only a small and indirect part in attribution of recent climate change [32] [33]

with TS and FtF preferring "significant" to "small".

If you look at the exec summary of the D+A chapter, you'll find vert little about the palaeo reconstructions [34]. If you look within the D+A chapter, you'll find One of the most important applications of this palaeo-climate data is as a check on the estimates of internal variability from coupled climate models, to ensure that the latter are not underestimating the level of internal variability on 50 to 100 year time-scales (see below). The limitations of the instrumental and palaeo-records leave few alternatives to using long “control” simulations with coupled models (see Figure 12.1) to estimate the detailed structure of internal climate variability. [35] which explicitly downplays their role. If you continue through that chapter, you'll find pages and pages of stuff, but you won't find the HS there at all, at least as far as I can see. So the idea that the HS is "significant" is unsupported.

Against this is set the SPM [36]. But even there, the HS only appears in 1 of 7 paras.

The HS has clearly appeared a lot in public discussion; but reading the actual report makes it clear that it has *not* played a major role in D+A. Hence small is correct; significant just reflects wishfull thinking and/or inability to distinguish the science and politics William M. Connolley 13:23, 21 November 2006 (UTC)

If you are trying to claim that the hockey stick did not have significance in the SPM, then you and I are reading different SPMs.  TheSeven 13:42, 21 November 2006 (UTC)
This article isn't about the SPM. Its about the temperature record. The particular piece in dispute is *how the palaeo record is used in attribution*. If you think its about how the HS is used in the SPM, then that may well explain the problems we're having. Now thats been made clear, how about you go round again and examine the actual point at issue, using the links I've helpfully provided above? William M. Connolley 14:08, 21 November 2006 (UTC)
The paleoclimatology was seen as so important that it is on the first page of the summary of the IPCC report. IPCC said that comparing recent changes with previous variability was part of attribution (1 of 3 or 4 parts of the attribution argument). They did not say it was minor; your blog did. Your analysis of numbers of paragraphs is original research. But while you insist in having your playing down of the temperature record in the introduction and on playing with words to mean what you want them to mean rather than the impression given to readers, you see no dispute. If this article is not about how the IPCC used the temperature record, don't include that bit at all. --Facethefacts 17:58, 21 November 2006 (UTC)
The palaeo stuff was new and interesting, so it got featured. But you are failing to see past the headlines to the science, even though I've pointed you to it several times. Its only a minor part of D+A, as you can see from looking at the chapter. Your bit about OR is funny; apparently you're allowed to assess it as "sig" (even though IPCC nowhere says this) but anyone else may not analyse to the opposite. Fact the Facts old fruit (you have it in your name but aren't very good at doing it): the HS doesn't even appear in the D+A chapter. Putting the HS into perspective is a valuable part of the argument, which is why it appear on the page, especially as misunderstandings like yours are so common William M. Connolley 19:05, 21 November 2006 (UTC)
Either you are lying or playing with words again. Mann's work is mentioned in [37] in Chapter 12, with a link to figure 2.21 [38]. --Facethefacts 20:17, 21 November 2006 (UTC)
How gracious of you. I'll take that as an implicit acceptance that the HS does indeed not appear - certainly I haven't seen it. And form the link provided the following quote is rather revealing: However, a number of difficulties, including limited coverage, temporal inhomogeneity, possible biases due to the palaeo-reconstruction process, uncertainty regarding the strength of the relationships between climatic and proxy indices, and the likely but unknown influence of external forcings inhibit the estimation of internal climate variability directly from palaeo-climate data. We expect, however, that the reconstructions will continue to improve and that palaeo-data will become increasingly important for assessing natural variability of the climate system. One of the most important applications of this palaeo-climate data is as a check on the estimates of internal variability from coupled climate models, to ensure that the latter are not underestimating the level of internal variability on 50 to 100 year time-scales (see below). The limitations of the instrumental and palaeo-records leave few alternatives to using long “control” simulations with coupled models (see Figure 12.1) to estimate the detailed structure of internal climate variability. I think that quote, to which you were kind enough to link, rather makes my point: that as far as D+A is concerned, the HS et al are of limited importance William M. Connolley 23:16, 21 November 2006 (UTC)
That is a deliberate deception and twisting of what I said. You left out the earlier lines "Palaeo-reconstructions provide an additional source of information on climate variability that strengthens our qualitative assessment of recent climate change. There has been considerable progress in the reconstruction of past temperatures. New reconstructions with annual or seasonal resolution, back to 1000 AD, and some spatial resolution have become available (Briffa et al., 1998; Jones et al., 1998; Mann et al., 1998, 2000; Briffa et al., 2000; Crowley and Lowery, 2000; see also Chapter 2, Figure 2.21)." That is the hockey stick and more, and you know it. And I read the words you quote as saying the temperature record of the past 1000 years is important but the reconstructions have been weak. If you honestly don't think that is what is being said then you are deluding yourself; otherwise you are deluding everybody else. --Facethefacts 00:57, 22 November 2006 (UTC)
The fact that the hockey stick appeared in SPM doesn't imply that it's central to the science as such. Remember, SPM is the abbreviation for "Summary for Policymakers." The SPM an attempt to frame the science in a way that is accessible to non-scientists. Such folks don't understand the finer points of radiative forcing and ice-albedo feedback, but they can (maybe) understand a graph of temperature trends. Raymond Arritt 19:57, 21 November 2006 (UTC)
Very patronising: non-scientists don't understand, so let's amuse them with pictures. No - the summary has the key and significant points. --Facethefacts 20:17, 21 November 2006 (UTC)
Not patronizing at all -- it's simply making the point that the SPM is expressed in terms that the intended audience is able to understand. Few policymakers are trained in physical science or numerical methods so they aren't equipped to handle the nuts and bolts of Gibbs fringes, ice-phase parameterizations, and the like. (Conversely, scientists tend to zone out when the subject turns to organization charts.) If the SPM was written in technical language it wouldn't be an effective summary. Again, the fact that a particular figure is included in the SPM means that it's effective in illustrative terms, not necessarily that it's central to the scientific underpinnings. Raymond Arritt 20:47, 21 November 2006 (UTC)
Still patronising, and still wrong. --Facethefacts 00:57, 22 November 2006 (UTC)

[edit] MBH, M&M usage

The article has a lot of confusion between the alternative names for each group of scientists. May I suggest that after the first mention that "Mann, Bradley, Hughes (1998) becomes simply "MBH98" and that the usage of "Mann et al (1998)" is dropped.Sparkzilla 06:04, 26 November 2006 (UTC)

Update:, I tried to work the above into an edit, but I abandoned it as it was harder than I first thought ;( It may be easier just to refer to the study (after initial mention) as "Mann's report", "Mann's study" and "Mann's hockey stick" In any case there needs to be some more consistency to the way the report is presented through the articleSparkzilla 06:35, 26 November 2006 (UTC)

I'm all in favour of consistency, but it's not just Mann's. Correctness is more important than convenience...--Stephan Schulz 07:21, 26 November 2006 (UTC)
I agree that this needs to be more consistent. As Stephan motes, simply using "Mann" isn't correct; there were two co-authors. The alternatives are "MBH98" and "Mann et al. (1998)". I prefer the latter as it's an accepted format in scientific journals and is less jargonish. Comments; or shall I be bold? Raymond Arritt 17:04, 26 November 2006 (UTC)

[edit] new evidence from Stieglitz

This weeks new scientist has an article on Climate change sceptics lose vital argument. Reporting on work of Stiegltz in Nature (vol 444, p601)[39](subscription required). Stiegltz seems to have a better model of the gulf stream which explains the little ice age and why its not reported in the hocky stick graph. Should something about this go in? --Salix alba (talk) 18:43, 4 December 2006 (UTC)

[edit] Article is badly POV and needs cleanup

After some recent cleanup and entries to achieve NPOV, WMC has reverted my edits and those of others. I have reverted. Both sides of the debate have to be presented. It is wikipedia policy. RonCram 15:48, 31 December 2006 (UTC)

I didn't blanket-rv your edits; unlike (sadly) you. I moved NRC out of the political bit, since it wasn't: that was science. I reverted your promotion of CA in the ext refs: I see no reason given for that, indeed you hid it. Well, we shall see what others say William M. Connolley 16:05, 31 December 2006 (UTC)

[edit] Time for a "Hockey stick controversy" page?

This page (and some others; notably McI and Mann biogs) are getting cluttered with the Hockey stick wars. They need to be mentioned here, but they shouldn't dominate the page. So I suggest creating a Hockey stick controversy page to move most of that stuff (NSC, Wegman, etc) into. Comments? William M. Connolley 22:03, 7 January 2007 (UTC)

I agree, as I first got involved in this page when trying to find out about said controversy and think it would be far better for the average reader if the controversy was made seperate Sparkzilla 00:05, 8 January 2007 (UTC)
Nuts. "Hockey stick" gets caught in my website blocker at work, since it's obviously sports related ;) and it would be too much of a pain to get an exception. Is there a redirect available without the work Hockey? (it's the URL, not the text, that matters.) --Spiffy sperry 15:26, 10 January 2007 (UTC)
You can make your own easily enough! William M. Connolley 16:13, 10 January 2007 (UTC)
Retrieved from "http://en.wikipedia.org../../../t/e/m/Talk%7ETemperature_record_of_the_past_1000_years_820f.html"