“Dealing a Mortal Blow” to the MWP

There has been a considerable amount of speculation over the past few years about which “leading” climate scientist told David Deming that we have to “get rid of” the Medieval Warm Period, including speculation (e.g. ukweatherworld) that it was Jonathan Overpeck (recently one of two Coordinating Lead Authors of AR4 chapter 6).

While the identity of Deming’s correspondent remains uncertain, a Climategate letter from January 13. 2005, written as an instruction from Overpeck as Coordinating Lead Author to IPCC Lead Authors Briffa and Osborn (cc Jansen, Masson-Delmotte), states that Overpeck wants to “deal a mortal blow” to the MWP (and Holocene Optimum) “myths” (480. 1105670738.txt).

Subject: the new “warm period myths” box

Hi Keith and Tim –

In reading Valerie [Masson-Delmotte]’s Holocene section, I get the sense that I’m not the only one who would like to deal a mortal blow to the misuse of supposed warm period terms and myths in the literature. The sceptics and uninformed love to cite these periods as natural analogs for current warming too – pure rubbish.

So, pls DO try hard to follow up on my advice provided in previous email. No need to go into details on any but the MWP, but good to mention the others in the same dismissive effort. “Holocene Thermal Maximum” is another one that should only be used with care, and with
the explicit knowledge that it was a time-transgressive event totally unlike the recent global warming.

Thanks for doing this on – if you have a cool figure idea, include it.
Best, peck

[Update – Apr 10, 2010. In an email on Jul 18, 2005 (551. 1121721126.txt), Briffa wrote Overpeck, Jansen and Crowley, expressing concern about a figure that Crowley had proposed observing:

there are intonations in some of Peck’s previous messages that he wishes to “nail” the MWP – i.e. this could be interpreted as trying to say there was no such thing..

To which Overpeck responded: 552. 1121869083.txt

SORRY TO SCARE YOU. I **ABSOLUTELY** AGREE THAT WE MUST AVOID ANY BIAS OR PERCEPTION OF BIAS. MY COMMENT ON “NAILING” WAS MADE TO MEAN THAT ININFORMED PEOPLE KEEPING COMING BACK TO THE MWP, AND DESCRIBING IT FOR WHAT I BELIEVE IT WASN’T.

OUR JOB IS TO MAKE IT CLEAR WHAT IT WAS WITHIN THE LIMITS OF THE DATA. IF THE DATA ARE NOT CLEAR, THEN WE HAVE TO BE NOT CLEAR. THAT SAID, I THINK TOM’S FIGURE CAPTURED WHAT I HAVE SENSED IS THE MWP FOR A LONG TIME, AND BASED ON OTHER SOURCES OF INFO – INCLUDING KEITH’S PROSE. THE IDEA OF A FIGURE, IS THAT FIGURES CAN BE MORE COMPELLING AND CONNECT BETTER THAN TEXT. ALSO, THERE ARE MANY WAYS TO LOOK AT THE MWP, AND AS LONG AS WE DON’T INTRODUCE BIAS OR ANYTHING ELSE THAT WILL DILUTE THE MESSAGE IN THE END, THE IDEA IS TO SHOW THE MWP IN MORE WAYS THAN TWO (THAT IS, THE EXISTING FIGS IN THE TEXT THAT KEITH AND TIM MADE).

[end update]

Oddly, given Overpeck’s commitment to “dealing a mortal blow” to the “misuse” of the MWP, in another Climategate letter, he didn’t like speculation about him being the one who wanted to “get rid of” the MWP (see 868. 1206628118.txt in March 2008.)

David Holland had written Overpeck, referring to speculation at ukweatherworld that Overpeck was the “get rid of the MWP” scientist, and seeking a statement from Overpeck.

Overpeck wrote to Jones, Mann, Santer, Susan Solomon and Keith Trenberth seeking advice on how to respond, telling them that he didn’t remember any such exchange, but conceding the possibility that Deming is quoting “out of context”:

I have no memory of emailing w/ him, nor any record of doing so (I need to do an exhaustive search I guess), nor any memory of him period. I assume it is possible that I emailed w/ him long ago, and that he’s taking the quote out of context, since know I would never have said what he’s saying I would have, at least in the context he is implying.

Overpeck says that he is reluctant to publish a statement on the matter for fear that Deming would “then produce a fake email”.

Any idea what my reaction should be? I usually ignore this kind of misinformation, but I can imagine that it could take on a life of it’s own and that I might want to deal with it now, rather than later. I could – as the person below suggests – make a quick statement on a web site that the attribution to me is false, but I suspect that this Deeming guy could then produce a fake email. I would then say it’s fake. Or just ignore? Or something else?

Jones wrote back, informing Overpeck that Holland had been making FOI requests, mentioning that he was off with Mann to Tahiti the next week:

I’m away all next week – with Mike. PaleoENSO meeting in Tahiti – you can’t turn those sorts of meetings down!

To a third party, it’s hard to understand why someone who wants to “deal a mortal blow” to the “myth” of the MWP would take exception to being labeled as someone who wanted to “get rid of” MWP. The objective in each case seems pretty much the same.

Maybe it’s just a vocabulary thing. Perhaps Overpeck feels that the term “getting rid of” is a little too Tony Soprano-ish for the “Director of the Institute for the Study of Planet Earth”, whereas the term “dealing a mortal blow” has the right sort of Arthurian cadence for Overpeck, who would rather be cast as Sir Launcelot than Tony Soprano.

Be that as it may, while Overpeck was concerned that Deming might produce a “fake email” purporting to show Overpeck seeking to “get rid of the MWP”, Overpeck hasn’t challenged the authenticity of the Climategate email in which he aspires to “deal a mortal blow” to the MWP.

Postscript: for the nth time, note that the position of the MM articles and many CA posts is that the multiproxy studies relied upon by IPCC do not prove that the modern warm period is warmer than the MWP. This doesn’t mean that we’ve claimed to have established the opposite or that some future scientist couldn’t prove the point with better proxies.

87 Comments

  1. George
    Posted Apr 8, 2010 at 8:22 AM | Permalink

    It seems pretty clear in his email that he only wants to “deal a mortal blow” to the “misuse” of the MWP, rather than deny its existence completely. Perhaps this was his objection to Deming’s statements.

    • Al Gored
      Posted Apr 8, 2010 at 6:07 PM | Permalink

      Oh I think we know just what he meant by the term “misuse.” That is, to use it in any that questioned the IPCC orthodoxy.

      Given the whole context here, there seems to be littl;e doubt about that.

  2. Gerald Machnee
    Posted Apr 8, 2010 at 8:33 AM | Permalink

    He does not explain what “misuse” means or whether the MWP was limited. Of course we are taking this out of context like everything else.

  3. Posted Apr 8, 2010 at 8:51 AM | Permalink

    Norfolk called…
    Little ol me, climate science spectator, sitting way up in the bleachers near the rafters, got a call from the Norfolk Police today. The detective constable was friendly and polite. But I couldn’t help him in any way. I couldn’t resist asking him why he had gone so far down the food chain as to question me.
    He said, “We’re leaving no stone unturned”.
    I wonder how many other blog readers got such a call.

  4. Barry Woods
    Posted Apr 8, 2010 at 8:58 AM | Permalink

    I’m away all next week – with Mike. PaleoENSO meeting in Tahiti – you can’t turn those sorts of meetings down!”

    Now there are 2 interpretations of this..

    the meeting is very exciting.

    or I can’t wait to jet across the world spewing CO2 everywhere, to have a lovely holiday, at someoneelses expense. and go to a meeting… in tahiti, minions, the poor will starve to death beacuse of agw delusion food poverty, but i will not lead my example..

    harsh comment?

    the public, may not grasp the science, they will grasp this… following:

    1700 limos at copenhagen 140 private jets, 15,000 delegates.

    half a dozen people in a room, decided what was going to happen (not a lot)

    15,000 people on a little 2 week junket..
    114 official party (sic) from australia alone

    remind the public the politicians actions vs the rhetoric…

    I’m still waiting for Gordon Brown to tell me how to prepare for planetary death..

    after all 50 days to save the planet- he said, that was minus how many hundred days now?

    • Hoi Polloi
      Posted Apr 8, 2010 at 1:50 PM | Permalink

      Tahiti, aren’t there beautiful beaches which could be spoiled in the coming rise of the sea level? I’m sure there’s plenty of coral around also.

    • ThinkingScientist
      Posted Apr 8, 2010 at 3:41 PM | Permalink

      I work in the oil industry and I have chaired a number of forums and workshops. When choosing a venue for future forums one of the strongest feedbacks I get from oil company staff is that holding the forum, conference etc in a location that is perceived as exotic or desirable is likely to result in their application to attend being declined by their employer.

      Striking contrast to the AGW junket…Bali, Rio or Tahito anyone?

      • Brooks Hurd
        Posted Apr 9, 2010 at 4:13 PM | Permalink

        It would seem that the climate science community intentionally selects exotic locales for its conferences. Isn’t it wonderful that they visit all these wonderful places with all their expenses covered by those of us who pay taxes?

  5. clivere
    Posted Apr 8, 2010 at 9:08 AM | Permalink

    The issue of how Overpeck got implicated as the writer of the email is a topic I have researched.

    In my opinion it was started by unfounded idle speculation by a poster called Andre at Ukweatherworld and other forums.

    Whilst Overpeck may have been part of the scientific effort to remove the MWP I doubt that he was the author of the email to David Deming.

    I can find no basis for Overpeck to have correspondence with Deming in 1995 but am aware of 3 other authors of the SAR who may have had cause for email correspondence with Deming at that time. My own view is that one of those 3 would most likely have written the email. Andre did not research the topic properly and his foundation for naming Overpeck is basically rubbish.

    As further background in January 2009 David Deming made the following email reply to Geoff Brown as posted at a couple of blogs including Jo Nova

    http://joannenova.com.au/2009/06/the-wong-fielding-meeting-on-global-warming/

    “I don’t have a copy of the email in question.

    When I received it, around 1995, global warming was
    not the contentious issue it is today. So, although
    I thought the message was astounding, I did not
    bother to archive a copy.

    Therefore, I am only 99 percent certain of the
    identity of the person in question.

    I have told people orally what my recollection is.

    But I have never given the name in writing, because
    I cannot be absolutely certain.

    In any event, the real significance is not the identity
    of an individual, but that science is being twisted and
    perverted to serve an ideology.

    David Deming
    Associate Professor
    College of Arts and Sciences

    College of Earth and Energy
    University of Oklahoma
    100 E. Boyd St., Room 510
    Norman, OK 73019 USA”

    This tells me a couple of things.

    1. Dave Deming has only told people verbally who the author of the email was. Those people who have speculated about Overpeck would have had to have met Deming to have the information. I cant find any evidence of Andre (UK Weatherworld, Steve McIntyre, Steve Milloy, Tim Ball or Richard Lindzen having met David Deming to get the name. I cant rule out that one of those people who have speculated about or named Overpeck could have got the name from Deming but I suspect not.

    2. Deming no longer has the email and his memory of the content is all that can be relied on for context.

    It is possible that the email could resurface if there was a second Climategate at a major US Institution. I doubt that it would turn up at the University of Arizona but would most likely turn up at Asheville NC or at Lawrence Livermore

    • Steve McIntyre
      Posted Apr 8, 2010 at 9:36 AM | Permalink

      Re: clivere (Apr 8 09:08),

      I agree that it’s unlikely that we’ll ever know who sent the “get rid of” the MWP email. However, we do know who sent the email wanting to “deal a mortal blow” to the MWP “myth” – it was Overpeck.

      • Dave G
        Posted Apr 8, 2010 at 2:08 PM | Permalink

        You’re twisting his words. He actually said:

        “I’m not the only one who would like to deal a mortal blow to the misuse of supposed warm period terms and myths in the literature”

        I’m not sure how one can get rid of the misuse of myths, but it’s quite clear he’s referring to wanting to get rid of misuse and myths about the MWP, rather than describing the MWP as a myth itself.

        Cheers,

        Dave

        Steve: What is the “myth” that he’s trying to get rid of.. if it isn’t the MWP itself?

        • Dave G
          Posted Apr 8, 2010 at 3:59 PM | Permalink

          Steve, I just can’t read what he wrote and square it with the meaning you’re trying to force on it. He simply does not describe the MWP as a “myth”.

        • Pat Frank
          Posted Apr 8, 2010 at 5:04 PM | Permalink

          Overpeck’s words: “…. misuse of supposed warm period … myths in the literature. The sceptics and uninformed love to cite these periods as natural analogs for current warming too – pure rubbish.

          I added the second ellipsis to bring out that “supposed warm period” applied to “myths” as well as to “terms.”

          It’s very clear that Overpeck considers the Medieval Warm Period itself a myth — a ‘supposed period‘ — likely in the sense of a global phenomenon. This reading is reinforced by Overpeck’s next sentence, which dismisses the MWP as an analogue for the current global warm period.

          The only rational reading of Overpeck’s words is that he considers the MWP itself a myth and counts himself among those who would like to deal it a “mortal blow; meaning to remove the idea from acceptable scientific parlance.

          Steve hasn’t twisted anything.

        • j ferguson
          Posted Apr 8, 2010 at 5:08 PM | Permalink

          Pat, I think you’ve got it. “supposed warm period” is the key.

        • Posted Apr 8, 2010 at 9:59 PM | Permalink

          Or he could have said, “You suppose. I deny.”

          Meanwhile, archeologists the world over commonly find evidence worldwide of the Medieval Warm Period (and the Little Ice Age and the Roman Warm Period, etc.) and base their concepts and understandings of the rise and fall of civilizations upon its sturdy, constant and reliable foundations…

        • Pat Frank
          Posted Apr 8, 2010 at 10:42 PM | Permalink

          Right on, j.

        • tty
          Posted Apr 9, 2010 at 5:17 AM | Permalink

          And when people started studying climate history about a hundred years ago the “Holocene Thermal
          Maximum” (then called the “Climate optimum”) was just about the first thing they found, it was so obvious.

          Now it may only “be used with care”.

        • kramer
          Posted Apr 8, 2010 at 11:42 PM | Permalink

          Dave G.,

          Right after he says

          “I’m not the only one who would like to deal a mortal blow to the misuse of supposed warm period terms and myths in the literature”

          … he then follows it with …

          “The sceptics and uninformed love to cite these periods as natural analogs for current warming too – pure rubbish.”

          It’s pretty clear to me that his undershorts are in a wad over the MWP and the skeptics use of it.

      • clivere
        Posted Apr 8, 2010 at 6:13 PM | Permalink

        Steve – you as much as anyone should be aware that the context and timing of emails is often as important as the content.

        The original email to David Deming dates to 1995. We dont know the context but I am quite prepared to believe the view expressed by David Deming that it reflects a desire by at least one researcher to alter the historical record to meet a desired objective. If the stated view of David Deming is eventually proven to be correct then that would be a strong reason to doubt work by that researcher. I personally would not trust any of their work without strong independent unbiased verification.

        The 1995 email pre-dates the work by MBH and Overpeck published in 1998. The members of the paleo community produced work that enabled the objective stated in the 1995 email but I have not seen anything to link any of the US based Paleo researchers to David Deming.

        It is certainly a possibility but still not proven that some Paleo researchers were directly working towards meeting the stated “must get rid of the MWP” objective. However it is also quite possible that their published work was done independently and reflects their own position.

        The 2005 email by Overpeck is 10 years on and post dates the research. I have seen evidence that Overpeck is not a believer of a significantly warm and global MWP. His view may well result from own research and it is therefore quite legitimate for him to privately express that view. I have not seen any evidence other than idle speculation that in 1995 he was writing emails to David Deming.

        Steve: Perhaps a more salient question at present is whether Overpeck’s desire to “deal a mortal blow” to the “myths” of previous warm periods had a deleterious effect on the fairness and accuracy of the AR4 assessment.

        • clivere
          Posted Apr 8, 2010 at 6:43 PM | Permalink

          I would agree based on other evidence that some IPCC authors have been promoting their own viewpoint and research.

          It has been demonstrated in a number of cases that objectivity is missing and that valid alternative viewpoints have been excluded.

          I would not myself be able to point to an example specific to Overpeck but would be interested if you do have examples. I would also be interested if you have any specific info about how and when Overpeck got appointed to an IPCC role and who initiated it.

          Steve: on the last point, don’t know. On the objectivity question, take a look at my next post for a potential incident/

  6. Acton Now
    Posted Apr 8, 2010 at 9:20 AM | Permalink

    The trick when flattening an MWP is to give it a mortal blow with a big hammer…

    Subject: Keith’s box
    Date: Mon, 17 Jan 2005 11:16:32 -0700

    Hi all – attached is Keith’s MWP box w/ my edits. It reads just great
    – much like a big hammer. Nice job.

    Please insert after Eystein has had his say. thx, Peck

  7. timetochooseagain
    Posted Apr 8, 2010 at 9:44 AM | Permalink

    What does “time transgressive event” even mean?

    • Craig Loehle
      Posted Apr 8, 2010 at 9:56 AM | Permalink

      “Time transgressive” means that it was not simultaneous over the globe. A good example is the warming at the last glacial termination. Because the ice sheets took so long to melt, the warming took longer to reach eastern Canada which still had ice. Thus a peak in warming moved across the northern regions and individual records of climate will not agree on the date of the warming. To say this applies to the Holocene Optimum at 8,000 to 6,000 BP is not a documented result, and to say it applies to the MWP is without foundation at all, but is a “clever way to deal with a problem” (that, and claiming it was only Europe that got warm at the MWP).

  8. fFreddy
    Posted Apr 8, 2010 at 9:49 AM | Permalink

    What the blazes is a “time-transgressive event” ?

  9. fFreddy
    Posted Apr 8, 2010 at 9:49 AM | Permalink

    Heh … snap …

  10. Sean
    Posted Apr 8, 2010 at 10:13 AM | Permalink

    “Maybe it’s just a vocabulary thing. Perhaps Overpeck feels that the term “getting rid of” is a little too Tony Soprano-ish for the “Director of the Institute for the Study of Planet Earth”, whereas the term “dealing a mortal blow” has the right sort of Arthurian cadence for Overpeck, who would rather be cast as Sir Launcelot than Tony Soprano.”

    Genius!!

  11. bill-tb
    Posted Apr 8, 2010 at 10:36 AM | Permalink

    I remember going to London, and asking why the Brits had foolishly named streets after grapes and wines. The answer from my Brit ‘minder’ came quickly, England used to have a wine industry using local vineyards. It was once so warm, around 1000 AD that grapes thrived outside of London. “The French hated us for it”, said my Brit minder.

    Burying the MWP is a must if the AGW myth is to survive. I mean, how many SUVs were the Vikings driving around on Greenland in 1000 AD.

    Re-Wiring history is an enormous almost impossible job, they are finding out.

    • Sean
      Posted Apr 8, 2010 at 2:28 PM | Permalink

      Which streets? Can you give a few examples?

      • Martin A
        Posted Apr 8, 2010 at 3:48 PM | Permalink

        Two mintures with Google maps gave the following:

        Vine St Westminster, London SW1, UK
        Vine St, Evesham, Worcestershire WR11, UK
        Vine St, Manchester, Lancashire M11, UK
        Vine St, Salford, Lancashire M7, UK
        Vine St, Hillingdon, Greater London UB10 0, UK
        Vine St, Wallsend, Tyne And Wear NE28, UK
        Vine St, Cleckheaton, West Yorkshire BD19 3DN, UK
        Vine St, Hillingdon, Uxbridge, Middlesex UB8, UK
        Vine St, Pemberton, Wigan, Lancashire WN1, UK
        Vine St, Billingborough, Sleaford, Lincolnshire NG34 0QE, UK
        Vine Street Clovenfords Galashiels TD1 3LU
        Vine St Clovenfords, The Scottish Borders TD1 3, UK
        Vine St, Clovenfords, TD1 3, UK
        Vine Rd, Great Sutton, Ellesmere Port, Merseyside CH66 2XX, UK
        Vintner St, Glasgow, Glasgow City G4 9, UK
        Vineyard Rd, Birmingham, West Midlands B31, UK
        Vineyard Rd, Wellington, Telford, Shropshire TF1, UK
        Vineyard Rd, Hereford HR1 1TT, UK
        Vineyard Rd, Peterborough PE1 1, UK
        Vineyard Rd, Much Wenlock, Shropshire TF13 6, UK
        Vineyard Rd, Feltham, Middlesex TW13 4HQ, UK
        Vintner Road, Abingdon OX14 3PF, United Kingdom‎ – 07976 613 016‎
        Wine St, Llantwit Major, South Glamorgan CF61 1RZ, UK
        Wine St, Bradford-on-Avon, Wiltshire BA15, UK
        Wine St, Pontlottyn, Bargoed, Mid Glamorgan CF81 9PH, UK
        Wine St, Frome, Somerset BA11, UK
        Wine St, Yeovil, Somerset BA20 1PW, UK
        Wine St, Devizes, Wiltshire SN10 1AP, UK
        Wine St, Leeds LS1 2, UK
        Wine St, Bath, Avon BA1 1TQ, UK

  12. j ferguson
    Posted Apr 8, 2010 at 11:03 AM | Permalink

    Somehow, dealing a mortal blow to misuse of MWP does not necessarily seem the vile thing this post implies.

    Suppose what is meant is a blow to assumptions that the forcings or conditions which contributed to the MWP had any commonality with those imagined to be contributing to today’s “warming?”

    On the other hand, offering a mortal blow to the assumption that the life as we knew it did not stop at the peak of the MWP, does seem crazy.

    Steve, assuming the first explanation, was shooting down assumptions of “commonality” of causes such a bad thing?

    Steve: “Dealing a mortal blow” to erroneous assumptions and methods isn’t vile. Why would you put a word into my mouth that I didn’t use? I’m asking something different: 1) is there a material difference between “getting rid of the MWP” and what Overpeck is calling for in these emails? 2) does Overpeck’s language here increase the chances that he was the “get rid of the MWP” guy?

    • Craig Loehle
      Posted Apr 8, 2010 at 11:56 AM | Permalink

      Point out where they are dealing with commonality of causes–this seems to be strictly about the event and its magnitude (for both MWP and Holocene Optimum.

    • j ferguson
      Posted Apr 8, 2010 at 12:49 PM | Permalink

      Steve,
      I apologize for inferring any enthusiasm on your part in what looked to me like a condemnation of putting to death the MWP.

      Craig, what else could they mean by misuse? How could a belief in the “existence” of the MWP be a “misuse” of it?

      I sincerely hope that i’m not launching a “word game” here. I supposed they were concerned that skeptics were seizing on what appeared in the MWP to be a precedent to the warming we now may be enjoying. But for the MWP to have a more useful precedence, wouldn’t it have to share more characteristics than rates and magnitude of temperature change?

      I guess I supposed they had a more sophisticated concern. No, not the event itself, but the supposition that the environment and forcings of the MWP had anything to do with today.

  13. Mike Davis
    Posted Apr 8, 2010 at 11:32 AM | Permalink

    Any warming recorded in the recent past (Current warm period) is also Time Transgressive and not global as shown in all of the anomaly maps. With Overpeck’s reasoning we can also deal a hammer blow to the Myth of current “Global warming”

  14. JT
    Posted Apr 8, 2010 at 11:53 AM | Permalink

    These Jerks are getting taxpayer paid vacactions to exotic locations!! They may not be in it for the pay or the glory, but the perks are outstanding!!!!! There are several reverences to travel and meetings abroad in the trove of emails. Is that all they do?

    “I’m away all next week – with Mike. PaleoENSO meeting in Tahiti – you can’t turn those sorts of meetings down!”

  15. Pat Frank
    Posted Apr 8, 2010 at 12:10 PM | Permalink

    Someone needs to deal a “mortal blow to the misuse of supposed” paleo-temperature proxies. Presently, there aren’t any, and the wholly specious imposition of physical meaning onto numerical constructs is a “travesty.”

    • Scott Brim
      Posted Apr 8, 2010 at 3:31 PM | Permalink

      “….. Someone needs to deal a mortal blow to the misuse of supposed paleo-temperature proxies……presently there aren’t any …”

      Mr. Frank, may I ask you to offer your viewpoint concerning the validity — or possible lack thereof — of the Loehle-McCulloch 2008 paleotemperature reconstruction?

      steve: please discuss this on one of the Loehle threads.

  16. thefordprefect
    Posted Apr 8, 2010 at 12:17 PM | Permalink

    Today in greenland:
    http://www.greenland-guide.gl/reg-south.htm
    During the summer, South Greenland fully lives up to its Danish name, Green Land, as this is the most fertile part of the country. In fact most of the flora of Greenland grow in this particular region. The winter climate is relatively mild, and summer temperatures reaching 16-18°C are not uncommon. Because of these conditions, the economic life of this area is also very different from the rest of Greenland, with sheep farming and agriculture playing an important part. If you take a boat trip along the fjords you will see isolated sheep farms, some of which have paths and rough roads leading to them, while for others the only contact with the outside world is by boat or radio transmitter.

    The sheep are rounded up in September, and some 20,000 lambs are taken on flat-bottomed boats to the slaughterhouse in Narsaq, one of the three sizeable large towns in South Greenland.

    Many sheep farmers have built cabins near their farms, in which guests can stay for a day or two before they continue on foot to the next farm.

    The abundant fertility of this region was also the reason why Eric the Red chose to live in South Greenland in around 985 AD, after he was outlawed from Iceland.

    • tty
      Posted Apr 9, 2010 at 5:26 AM | Permalink

      Yes, but barley won’t ripen there even in this ‘unprecedented’ warm period, which it did (if barely) in the thirteenth century (ref. Konungs Skuggsjá). The do grow barley in South Greenland today, but it is only good for green fodder.
      By the way the norse did not settle only in South Greenland, but also in the Nuk area (Vestri bygd). This was deserted in about 1350, about a century or so before the main settlement (Eystri bygd).

  17. Posted Apr 8, 2010 at 12:18 PM | Permalink

    One of the most entertaining things about AR4 Ch6 is that they have this box (page 468) with a figure of carefully selected proxies showing no MWP, but on the previous page there is a figure (6.10) showing a very clear MWP at 1000 AD.

    The wording of the post title is a bit naughty.

  18. thefordprefect
    Posted Apr 8, 2010 at 12:21 PM | Permalink

    The MWP in words:
    The words in this collection of reports are often about severe winters.

    http://booty.org.uk/booty.weather/climate/751_999.htm

    759/760 (Winter) A cold winter. (Easton, in CHMW/Lamb) [ Some accounts have this as 761 .. usual dating problems ]. 1
    763/64(Winter & later) The winter is noted as being ‘severe’ .. and was followed by a ” long and terrible drought ” .. in the spring/summer of 764: suggests abnormally persistent blocking / high pressure situation (at least, ‘abnormal’ in length of persistence in the same ‘phase’), with the primary jet perhaps shunted well to the south. Some sources note ‘great snow’, with an ‘intense’ frost. In ‘London Weather’ entry, …. “one of the severest winters known in history”. (Probably affected large areas of continental Europe, again suggesting a ‘Scandinavian High’ situation.) 1, 8
    ~770 – ~800 A period of higher frequency of cold winters (note: not necessarily every winter). This leads to the suggestion of blocking of the main Atlantic, westerly flow by often slow-moving, intense anticyclones, or an increased frequency of east or northeast flow with higher pressure to the north of these islands. This would tie in to a certain extent with the idea that Scandinavian exploration / raids were assisted by lack of ‘westerly-storminess’. 1
    798 (Winter) Ireland: snow – men & animals died. LWH
    ~800 (December) December 24th (original recorded as the ‘Eve of Christmas’, so presumably we must regard this as an ‘Old Style’ dating. Also, the exact year is subject to the same uncertainty as other events so long ago): gale: Great SW or W wind. Cities destroyed (!); Lamb has this comment in ref. 23: ” The first recorded one of a series of storm floods .. which reduced the size of the island of Heligoland by more than half by the year 1300.” LWH, 23
    804 (March) March 17th: Ireland – Tornado(?): thunder, wind & lightning. ‘1010 men killed’. [ I wouldn’t normally detail all ‘tornado’ events, but the death-toll warrants mention, and I do wonder given that over a thousand died, whether this was in fact a ‘storm’ event due to a major depression rather than a small-scale tornadic event.] LWH
    817 (Winter) December 25th (presumably logged as ‘Christmas Day’): Ireland – snow: many rivers & lakes frozen to February 22nd. [ Although only tied to Ireland, given the severity & length of the event, Britain must also have been affected. ] LWH
    821/822 (Winter) A severe winter. (Easton, in CHMW/Lamb) 1
    827 Possible severe winter. Thames frozen for nine weeks. 8, LWH
    844/845 (Winter) A cold winter. (Easton, in CHMW/Lamb) 1
    850
    855/856 (Winter) A cold winter. (Easton, in CHMW/Lamb); Great ice & frost until Jan. 7th – rivers & lakes froze. 1, LWH
    856 Ireland: gale: very great wind; woods felled. LWH
    859/60 (Winter) A severe winter in England. 1, 8
    873/874 (Winter) A cold winter. (according to Easton, in CHMW/Lamb); Scotland: specifically a cold winter – great frost from November to April; thaw brought floods. 1,LWH
    880/881 (Winter) A cold winter. (Easton, in CHMW/Lamb) 1
    892(?) (November) 11th November: Ireland – gale, many trees and houses fell. LWH
    908 Possible severe winter. Most English rivers frozen for two months. 8,LWH
    910 – 930 Extended droughts with regularity: also thought that the summer half-years were warm or very warm more often than not – some notably hot summers. 1
    912/913 (Winter) A severe winter. (Easton, in CHMW/Lamb) 1
    917(Winter) Ireland: severe winter – Great snow. Lakes frozen. [ As elsewhere, implies a blocked pattern, with occasional ‘Atlantic’ incursions. Must have affected Britain as well I would have thought.] LWH
    923 Possible severe winter. Thames frozen for 13 weeks. Year may be 928 or 929. 8,LWH
    927/928 (Winter) A cold winter. (Easton, in CHMW/Lamb) 1
    939/940 (Winter) A cold winter. (Easton, in CHMW/Lamb) 1
    941(Winter) Ireland: cold – Lakes & rivers froze. [ I wonder if this belongs to the winter noted above? ] LWH
    944 Possible severe gale/storm in London; many houses destroyed. 1500 houses “fell” (destroyed?): affected the whole of England. 8,LWH
    946 – 948 England: drought – ‘no rain for 3 years’ (unlikely to have been “no” rain – more likely a marked shortage of rainfall / winter snowfall). LWH
    955 (Summer) Wales: Hot summer. [ Must surely have affected other parts of Britain – indeed, the heat may have been ‘exceptional’, if the summer was notably hot as far west as Wales.] LWH
    973 Thames flood in London. 8
    974/75 (Winter) Probably a severe winter across Britain .. usual doubts about dates etc. Severe winter over whole of Europe until March 11th (OS). 1, 8, LWH
    990’s Extended droughts with regularity: also thought that the summer half-years were warm or very warm more often than not – some notably hot summers. 1
    992 Ireland: Storm flood – tempest (high wind?) submerged island fort in one hour Wicklow. [ The way this is written up suggests that this was a ‘storme surge’ event, rather than necessarily due to heavy rain – though the latter may have played a part.] LWH
    995(Summer) Summer cold throughout Europe; severe frost & ice (quite remarkable if true in July as given on this site!) LWH
    998 Possible severe winter. Thames frozen for five weeks

  19. Gary P
    Posted Apr 8, 2010 at 12:22 PM | Permalink

    “Postscript: for the nth time, note that the position of the MM articles and many CA posts is that the multiproxy studies relied upon by IPCC do not prove that the modern warm period is warmer than the MWP. This doesn’t mean that we’ve claimed to have established the opposite or that some future scientist couldn’t prove the point with better proxies.”

    Yes, I understand that CA has not gotten into making original temperature reconstructions based on proxies, but when were proxies ever proven to be the the only method of determining temperature for a given point in time? The hope is that proxies could provide a continuous reconstruction but the Greenland settlements and the body in the ice in the high pass,
    https://climateaudit.org/2005/11/18/archaeological-finds-in-retreating-swiss-glacier/,
    provide much more definitive temperature indication for one point in time than any known proxy can.

    A huge problem with the proxy studies is the failure to compare (and calibrate) the proxies with historical records and archeological finds. These must be taken as much more definitive than the proxies which respond to many variables.

  20. Posted Apr 8, 2010 at 12:25 PM | Permalink

    Then there is the LIA
    http://booty.org.uk/booty.weather/climate/1650_1699.htm
    Many hot summers.

  21. Steve McIntyre
    Posted Apr 8, 2010 at 12:25 PM | Permalink

    Folks, please do not debate the MWP as most of the relevant points have been made. The issue here is a smaller one: is there a difference between Overpeck’s language here and “getting rid of the MWP”? And does Overpeck’s attitude exemplified in these emails increase or decrease the probability that he is the “get rid of the MWP” mystery man (the answer to which we’ll probably never know)?

    I’ll discuss Overpeck and the Holocene Optimum in a separate forthcoming post.

    • Pat Frank
      Posted Apr 8, 2010 at 5:09 PM | Permalink

      If David Deming took more than 24 hours to delete the email, it may still be resident on a University backup server. I wonder how that possibility could be determined.

  22. Posted Apr 8, 2010 at 12:45 PM | Permalink

    What it really comes down to is

    How would you explain causev of the MWP?

    solar output is believed to be simalar to current values (certainly within the limits that would give .2C difference.

    Milankovitch cycles may be a cuse see this graphic.

    This shows:
    Current insolation 480
    1000 years ago perhaps 530

    So ifg this is the cause of MWP then we have reached the same temperature with 10% less insolation. Is this due to GHGs or is there another explanation?

    • Niels A Nielsen
      Posted Apr 8, 2010 at 1:49 PM | Permalink

      Your linked graphic doesn’t support your statement. ky means thousand years….

  23. Don B
    Posted Apr 8, 2010 at 12:47 PM | Permalink

    Jasper Kirkby of the European Organization for Nuclear Research shows graphs of temperature proxies back to 900 AD on page 3. Overpeck and friends have a lot of work to do to destroy evidence of MWP.

    Click to access 0804.1938v1.pdf

  24. agw_skeptic99
    Posted Apr 8, 2010 at 12:52 PM | Permalink

    Please stop with the ‘modern warm period’. MWP has been in common use for a long time and the acronyms are confusing enough already. How about LTCWP for late twentieth century or pick your own.

  25. Fred Harwood
    Posted Apr 8, 2010 at 1:19 PM | Permalink

    Heh! Keep ’em coming, Steve. Each one finds a larger audience.

  26. Carl Gullans
    Posted Apr 8, 2010 at 1:27 PM | Permalink

    Well steve, to answer your questions:

    1) There is a difference in the two comments. The “we have to get rid of the MWP” quote does not carry any context. And so, it obviously sounds worse than the above, in which Overpeck at least identifies that he believes “dealing a mortal blow” to the MWP would be the scientifically accurate thing to do (in his opinion).

    2) This increases the probability that Overpeck uttered the first phrase, but the current and previous probabilities are unknown (i.e. could still be very low, anybody could have said this). Unless you know something that we don’t?

  27. Fred
    Posted Apr 8, 2010 at 1:29 PM | Permalink

    So Greenland was a real estate scam after all . . . . damn those property developers of yore . . . they lie just like the modern ones selling real estate dreams of beach front property in Arizona.

  28. Posted Apr 8, 2010 at 1:36 PM | Permalink

    Having to deal a Mortal Blow” to the MWP might not take the same kind of effort as having to deal a mortal blow to the misuse of supposed warm period terms and myths in the literature.

  29. dearieme
    Posted Apr 8, 2010 at 1:44 PM | Permalink

    “to say it applies to the MWP is without foundation at all, but is a “clever way to deal with a problem” (that, and claiming it was only Europe that got warm at the MWP).” Gotcha. What he wants to do is HIDE THE INCLINE.

  30. Bernie
    Posted Apr 8, 2010 at 2:07 PM | Permalink

    If the question is one of Overpeck’s intent then I read his comment of Briffa’s framing of the MWP issue in AR4 “It reads just great – much like a big hammer. ”
    CRU email 1105978592.txt (Jan. 17, 2005) as a confirmation of his intent to pre-empt any use of the MWP to question the late 20C global temperature increase..

    In what I assume is “Keith’s comment” i.e., Box 6.4: Hemispheric Temperatures in the ‘Medieval Warm Period’ http://www.ipcc.ch/publications_and_data/ar4/wg1/en/ch6s6-6.html
    “Lamb’s analyses also predate any formal statistical calibration of much of the evidence he considered. He concluded that ‘High Medieval’ temperatures were probably 1.0°C to 2.0°C above early 20th-century levels at various European locations (Lamb, 1977; Bradley et al., 2003a). ” becomes
    “The uncertainty associated with present palaeoclimate estimates of NH mean temperatures is significant, especially for the period prior to 1600 when data are scarce (Mann et al., 1999; Briffa and Osborn, 2002; Cook et al., 2004a). However, Figure 6.10 shows that the warmest period prior to the 20th century very likely occurred between 950 and 1100, but temperatures were probably between 0.1°C and 0.2°C below the 1961 to 1990 mean and significantly below the level shown by instrumental data after 1980. “

    On reflection this does appear to be much of a hammer blow – though Figure 6.10 certainly would leave the casual reader with more of a sense of a hockey stick than Lamb’s schematic chart.

    As an aside and OT, I found the description of this figure very odd and the placement of the year 2000 somewhat disorienting given that the proxy record stopped in 1980. It also seems to start in the year 800 yet us normalized from 1001 to 1980.
    Figure 1. The heterogeneous nature of climate during the ‘Medieval Warm Period’ is illustrated by the wide spread of values exhibited by the individual records that have been used to reconstruct NH mean temperature. These consist of individual, or small regional averages of, proxy records collated from those used by Mann and Jones (2003), Esper et al. (2002) and Luckman and Wilson (2005), but exclude shorter series or those with no evidence of sensitivity to local temperature. These records have not been calibrated here, but each has been smoothed with a 20-year filter and scaled to have zero mean and unit standard deviation over the period 1001 to 1980.

    • Posted Apr 9, 2010 at 6:02 PM | Permalink

      Re: Bernie (Apr 8 14:07),

      Frank Lansner has been doing some interesting historical reviews over at WUWT. The one that’s pertinent here is http://wattsupwiththat.com/2010/04/04/ipcc-how-not-to-compare-temperatures/

      –he points out that IPCC is comparing “super-averaged” (40-yr filter there, 30 here) proxies vs. 5-yr averaged recent temps. More mendacity.

      I’ve always been uncomfortable with the comparison of proxy “apples” to instrumental “oranges” on all the IPCC (etc) HS charts — especially since the “blade” (as here) is almost exclusively the massaged instrumental temps — very likely biased high by leftover UHI (etc, etc.).

      It is interesting how well the proxy “decline” shows up on IPCC Fig. 6.10, even clipped short at circa 1970. Pity they don’t make the charts available without the instrumental overlay. Can’t imagine why they don’t ;-]

      If global temps continue their current plateau/decline, it will be interesting to see what new “trick” will come forward to sex up the scary blade….

      Cheers — Pete Tillman

  31. MCE
    Posted Apr 8, 2010 at 2:20 PM | Permalink

    Steve: I wonder if the wording in Valerie (Mason-Delmotte)’s Holocene section might provide clues to what Peck meant by “I get the sense that I’m not the only one who would like to deal a mortal blow to the misuse of supposed warm periods and myths in the literature.” Is Valerie’s paper available online?

  32. Tom C
    Posted Apr 8, 2010 at 2:20 PM | Permalink

    Steve:

    I think this E-mail from “Peck” strongly suggests that he is the “get rid of…” author. The key is the phrase “…dismissive effort”. This is not the sort of language that normal scientists use. As is typical of the Team, it is clearly indicative of coordinated political activity. “Dismissive effort” is required to “get rid” of something so massively documentated as the world-wide MWP.

    • justbeau
      Posted Apr 8, 2010 at 9:16 PM | Permalink

      Is Peck short for Overpeck? Or is he one of the Love Guru’s disciples?

  33. UK John
    Posted Apr 8, 2010 at 2:46 PM | Permalink

    Overpeck wants to get rid of “warm period myths”, and most bloggers on this site want to get rid of “warm period myths”.

    It appears we all have a lot in common, just a little difference of 1000 years between myths.

    • justbeau
      Posted Apr 8, 2010 at 9:05 PM | Permalink

      Good fun.

  34. Shallow Climate
    Posted Apr 8, 2010 at 3:12 PM | Permalink

    Been reading “Superfreakonomics”. Adapting a quip from that book, perhaps Overpeck”s stance is, “Sure, the MWP is true in reality, but is it true in THEORY?”

  35. PhilJourdan
    Posted Apr 8, 2010 at 3:41 PM | Permalink

    It makes you wonder if a second shoe willdrop with more released emails and such. It could just be a mis-understanding by the reporter, or another deep throat source we have yet to see.

  36. Barry Woods
    Posted Apr 8, 2010 at 3:42 PM | Permalink

    another Mortal BLOW to ‘alarmism’

    RealClimate are going to have fits over this, not for the content as such…

    Just WHO is writing it…

    “In 2005, Jones made it clear to one of his petitioners that he wasn’t going to do that:

    – Even if WMO [the World Meteorological Organisation] agrees, I will still not pass on the data. We have 25 or so years invested in the work. Why should I make the data available to you, when your aim is to try and find something wrong with it.-

    This cuts to the heart of the matter. Science must be falsifiable: otherwise it’s not science. Those who seek to find something wrong with your data are the first people who should have access to it, not the last. Challenging, refining and improving other people’s work is the means by which science proceeds.”

    Anybody guessed who it is yet?

    SAme journalist wrote today:

    “Jones reveals:

    I’m getting hassled by a couple of people to release the CRU station temperature data. Don’t any of you three tell anybody that the UK has a Freedom of Information Act!

    Since I began writing about this issue, I’ve been assailed by climate scientists and environmentalists, all insisting that Jones did nothing wrong. If these emails meet their standards of professional rectitude I dread to think what else they would find acceptable.”

    Do you know who it is yet!!!!

    I REALLY wonder what Real Climate will make of this..
    same journalist, Part of the Guardian environment network:

    “But there was a simple means of getting the hasslers off his back: release the sodding data.

    In 2005, Jones made it clear to one of his petitioners that he wasn’t going to do that:

    Even if WMO [the World Meteorological Organisation] agrees, I will still not pass on the data. We have 25 or so years invested in the work. Why should I make the data available to you, when your aim is to try and find something wrong with it.”

    It’s GEORGE MONBIOT: (Guardian)
    The chief eco journalist in the UK, who made Dr David Bellamy a deniar, has seen the light, and is getting out of Dodge.

    http://www.guardian.co.uk/environment/georgemonbiot/2010/apr/08/hacked-emails-freedom-of-information?showallcomments=true#comment-51

    Whatever the motivation of the questioners might have been, the original FoI requests appear to have been genuine attempts to obtain information. As the replies sent to one enquirer, Willis Essenbach, show, they were fobbed off in a way guaranteed to make anyone seethe with rage. The letters sent to him by CRU epitomise bureaucratic obfuscation of the kind that anyone who believes in democracy should challenge.

    The Canadian mining investor Steve McIntyre, who runs the website Climate Audit, was also fobbed off. In another email, Phil Jones reveals:

    Think I’ve managed to persuade UEA [the University of East Anglia] to ignore all further FOIA requests if the people have anything to do with Climate Audit.

    That doesn’t seem right either. Just because you don’t like someone doesn’t mean you can refuse to answer their FoI request.”

    Wonder if the BBC Richard Black or Roger Harrabin will be next…

    Of course they probably haven’t got around to actually looking at all the emails yet, or the code,or Harry_read_me.txt. Or the analysis of the above that very many people have kindly done for them.

    Or read ‘The Hockey Stick Illusion’ or ‘Climategate: the Crutape letters’

    I must dash over to RealClimate to see how they are taking it.
    They wil be having kittens..

  37. Jean Demesure
    Posted Apr 8, 2010 at 4:03 PM | Permalink

    The “Valerie Masson Delmotte” Overpeck talks about is the same climatologie who has initiated this week a petition of more than 400 of her warmist collegues urging the French Ministry of Research to trust them against the attacks of prominent skeptics Claude Allegre. Scientists demanding politicians to defend their science, how sweet !
    Undoubtedley, she wants to “deal a mortal blow” to skeptics as much as to the MWP.

  38. Mike Davis
    Posted Apr 8, 2010 at 4:29 PM | Permalink

    There are probably 20 names that could have written the original ” Get rid of the MWP” statement and Overpeck is among them and just suffering from selective “Don’t Recall”.

  39. Posted Apr 8, 2010 at 5:44 PM | Permalink

    I am startled by Overpeck’s fear that Deming would attack him with a fake email. Isn’t that an astonishing allegation? Can anyone see any factual basis for such a cloak-and-dagger expectation? What has happened to science here?

    • David
      Posted Apr 10, 2010 at 10:29 AM | Permalink

      This intrigued me as well. It is perhaps more then paranoid. If he thinks that perhaps he sent such an e-mail (at one point he states he cannot remember any such e-mail)then he may wish to preemtively dismiss its possible appearance as fake.

  40. B. Stockwell
    Posted Apr 8, 2010 at 5:55 PM | Permalink

    I really enjoy the comments/exchanges. The AGW skeptics have totally convinced me. – snip

    Steve: you shouldn’t be “convinced”. I dwell on IPCC papers and claims because I think that there’s a need for someone to do so. Don’t conclude from this that I believe that people have proved the opposite.

  41. Dave
    Posted Apr 8, 2010 at 6:06 PM | Permalink

    I happened to be born in a small house in Vineyard road Feltham, and yes even in the early fifties wild vines still grew.

  42. Roger Knights
    Posted Apr 8, 2010 at 9:08 PM | Permalink

    I read that ISPs keep copies of all e-mails sent and received, in case the gov’t. subpoenas them. If a mere user wanted them, he would probably have to compensate his ISP. But Deming could probably afford it. If not, he could take up a collection.

  43. MIke
    Posted Apr 8, 2010 at 9:21 PM | Permalink

    Deming, BTW, is an associate professor at Oklahoma University. Here is what his colleagues think of global climate change.

    Click to access climate_statement.pdf

  44. BlueIce2HotSea
    Posted Apr 9, 2010 at 12:11 AM | Permalink

    I’m not good at this.

    However, it could be that Overpeck feared Deming could actually produce a true email, so Overpeck is pre-emptively declaring it a fake.

    Reading these emails still makes me feel sick.

    • Roger Knights
      Posted Apr 9, 2010 at 12:34 AM | Permalink

      But if Deming can get hold of a copy from his ISP, it would be certified as authentic by his ISP.

      • BlueIce2HotSea
        Posted Apr 9, 2010 at 12:42 AM | Permalink

        Yes. Then the game is over.
        But why does Overpeck fear a “fake” email, one that Deming cannot certify? I told you I am not good at this.

    • BlueIce2HotSea
      Posted Apr 9, 2010 at 12:56 AM | Permalink

      OK How about this.
      Overpeck sent Deming an email, but not from his regular account, through an anonymizing service. So Deming knows it’s from peck, but he can’t prove it. But peck still worries that if a criminal investigation comes out of this, he could still be identified by a tracing mechanism he is unaware of. Yeegads. I’m done.

  45. Larry Huldén
    Posted Apr 9, 2010 at 2:03 AM | Permalink

    To “get rid of MWP” must have been a long term idea before 2001 report. May be Overpeck only discussed the issue with some people and later the sentence spread in a second hand email by someone else to Deming. This could be the reason why Deming doesn’t remember exactly who (not important person) sent the email and why Overpeck doesn’t remember exactly if he had sent such an email.

    • BlueIce2HotSea
      Posted Apr 9, 2010 at 11:29 AM | Permalink

      Yes. That is more plausible.

      In that case, Overpeck might fear the release because additional information in it might tie back to him, such as an unusual conference, seminar, etc.

      Oh, well.

  46. Posted Apr 9, 2010 at 9:14 AM | Permalink

    Regarding the objectivity of reconstructions and the MWP, Nic forwarded me an Ammann publication yesterday which had a nice open critique seciton.

    To the Drawing Board

    The reviewers and Ammann acknowledge all of the MWP supressing variance losses across the entire group of regression methods.

    It’s awesome.

  47. Peter Oneil
    Posted Apr 9, 2010 at 12:12 PM | Permalink

    In my humble opinion, it is very likely that overpeck was the initiator of the idea of dealing a mortal blow to the alledged myth of the MWP. Had he not done so, he should be quite certain, but claims not to be able to recall the event. Further, he then speculates that a fake e-mail might be forthcoming to coroborate the story. This suggests that he is preparing his colleagues for its arrival together with his defence ,which will be to refute it as a fake(hoax).
    Methinks the witness doth protest too much.

  48. D. Robinson
    Posted Apr 9, 2010 at 2:11 PM | Permalink

    From my first read of this post I choked on trying to equate “deal a mortal blow to the misuse of supposed warm period terms and myths in the literature.” with “get rid of the MWP”.

    IMO, they do not mean or imply the same thing. The wording of the first statement is very precise “misuse of supposed warm periods”.

    One could paraphrase Overpeck’s statement as “misuse [by skeptics] of supposed warm periods.”

    Seems like an over-reaction on our part.

  49. Steve McIntyre
    Posted Apr 10, 2010 at 12:07 PM | Permalink

    Added to text: In an email on Jul 18, 2005 (551. 1121721126.txt), Briffa wrote Overpeck, Jansen and Crowley, expressing concern about a figure that Crowley had proposed observing:

    there are intonations in some of Peck’s previous messages that he wishes to “nail” the MWP – i.e. this could be interpreted as trying to say there was no such thing..

    To which Overpeck responded: 552. 1121869083.txt

    SORRY TO SCARE YOU. I **ABSOLUTELY** AGREE THAT WE MUST AVOID ANY BIAS OR PERCEPTION OF BIAS. MY COMMENT ON “NAILING” WAS MADE TO MEAN THAT ININFORMED PEOPLE KEEPING COMING BACK TO THE MWP, AND DESCRIBING IT FOR WHAT I BELIEVE IT WASN’T.

    OUR JOB IS TO MAKE IT CLEAR WHAT IT WAS WITHIN THE LIMITS OF THE DATA. IF THE DATA ARE NOT CLEAR, THEN WE HAVE TO BE NOT CLEAR. THAT SAID, I THINK TOM’S FIGURE CAPTURED WHAT I HAVE SENSED IS THE MWP FOR A LONG TIME, AND BASED ON OTHER SOURCES OF INFO – INCLUDING KEITH’S PROSE. THE IDEA OF A FIGURE, IS THAT FIGURES CAN BE MORE COMPELLING AND CONNECT BETTER THAN TEXT. ALSO, THERE ARE MANY WAYS TO LOOK AT THE MWP, AND AS LONG AS WE DON’T INTRODUCE BIAS OR ANYTHING ELSE THAT WILL DILUTE THE MESSAGE IN THE END, THE IDEA IS TO SHOW THE MWP IN MORE WAYS THAN TWO (THAT IS, THE EXISTING FIGS IN THE TEXT THAT KEITH AND TIM MADE).

    [end update]

    • Tom C
      Posted Apr 10, 2010 at 2:22 PM | Permalink

      Much of this is incoherent. I’m not sure what he is trying to say.

    • Posted Apr 10, 2010 at 4:16 PM | Permalink

      SORRY TO SCARE YOU. I **ABSOLUTELY** AGREE THAT WE MUST AVOID ANY BIAS OR PERCEPTION OF BIAS. MY COMMENT ON “NAILING” WAS MADE TO MEAN THAT ININFORMED PEOPLE KEEPING COMING BACK TO THE MWP, AND DESCRIBING IT FOR WHAT I BELIEVE IT WASN’T.

      His beliefs are irrelevant. What does the evidence say?

    • harold
      Posted Apr 10, 2010 at 5:36 PM | Permalink

      Re: Steve McIntyre (Apr 10 12:07),

      I believe the crux of the Overpeck response is in:

      THERE ARE MANY WAYS TO LOOK AT THE MWP, AND AS LONG AS WE DON’T INTRODUCE BIAS OR ANYTHING ELSE THAT WILL DILUTE THE MESSAGE IN THE END

      So, there is a (political/other )message which must not be diluted, and this can be achieved by:

      , THE IDEA IS TO SHOW THE MWP IN MORE WAYS THAN TWO

      (i.e. by diluting the MWP through multiple interpretations) Does anyone here know where the FIGS/graphs by Tim and Keith are?

  50. charles the moderator
    Posted Apr 11, 2010 at 1:50 AM | Permalink

    IF THE DATA ARE NOT CLEAR, THEN WE HAVE TO BE NOT CLEAR.

    I know that’s not what he really meant, but it really funny in context.

  51. Posted Apr 16, 2010 at 10:08 AM | Permalink

    I thought it was only a joke …

  52. Posted Aug 26, 2012 at 4:14 PM | Permalink

    Reblogged this on Climate Ponderings.

7 Trackbacks

  1. By Meeting of the Minds « the Air Vent on Aug 30, 2010 at 10:11 PM

    […] Johnathan Overpeck –  Lead Author IPCC […]

  2. […] principal du GIEC (chapitre 6, AR4) et fut impliqué dans le Climategate (notamment en lien à la suppression de l’optimum médiéval, cette période gênante pour les carbocentristes)… Un avant-gout de la discussion […]

  3. […] On sait toutefois qu’Overpeck, lorsqu’il était coordonnateur principal du GIEC, a écrit aux auteurs principaux Keith Briffa et Tim Osborn : I get the sense that I’m not the only one who […]

  4. […] https://climateaudit.org/2010/04/08/dealing-a-mortal-blow-to-the-mwp/ […]

  5. […] expert is Jonathan Overpeck.  This is a man who openly discussed with the team about trying to get rid of the MWP and then saying he doesn’t remember saying this.  He’s an expert history […]

  6. […] Crowley’s Climategate recollection clearly shows the frustration of Hockey Team scientists in 1996: they felt (incorrectly IMO) that Bradley and Jones 1993 and Hughes and Diaz 1994 had refuted concepts of the Little Ice Age and MWP, but had nothing to substitute in its place. Thus, Bradley in 1991 and Crowley in 1996 had both ended up using the Lamb graphic – reluctantly but used nonetheless. It seems entirely plausible to me that Hockey Team scientists in 1995-96 really did want to “get rid of the MWP”. Even as late as 2007, Overpeck, as an IPCC Coordinating Lead Author, still wanted to “deal a mortal blow to the MWP” (see CA post here). […]

  7. […] https://climateaudit.org/2010/04/08/dealing-a-mortal-blow-to-the-mwp/ […]