Sunday, December 18, 2011


From: Tim Osborn <>
To: Tom Crowley <>,Keith Briffa <>
Subject: MWP figure
Date: Thu, 21 Jul 2005 16:07:58 +0100
Cc: Jonathan Overpeck <>, Eystein Jansen <>

Hi Tom,

In Keith's email below, when he says "we use series that total to Tom/Gabi
composite", he doesn't mean that *our* mock up of the figure uses these
series, but that if the series shown in *your* draft figure are the same as
those used in the Hegerl/Crowley recon that is currently submitted ("...a
twice validated climate record...") then we will go with *your* figure. It
is fine then to include the "composite series" and the instrumental data
and a temperature scale. Our previous concerns about these latter points
were that it might be seen as another new NH temperature
reconstruction. But if in fact the composite and its expression as a
temperature are not a new NH T recon, but are in fact identical to the
published (submitted, at least) Hegerl/Crowley NH T recon (which is already
included in the main intercomparison figure) then there's no problem.

Does your figure equate to the new Hegerl/Crowley NH T recon? If so, we
should go with your MWP figure, though the CLAs want me to draw it in the
same style as the others and also cut the time period down to a few
centuries spanning the MWP. Keith suggests beginning in 800 or 850.

Would it be possible therefore to send the data series you used for your
figure, but beginning in 800/850, so I can plot the figure in the required



At 14:53 20/07/2005, Tom Crowley wrote:
>Keith, if you can find more I see no problem - it seems that a lot of the
>data you used was via Cook and colleagues - I was unable to locate a full
>length record from Quebec in that time series, but maybe you are relying
>on something else - if so can I have it!?
>other suggestions: provide a more general label to sites - eg, mangazeyek
>(sp)/yamal could be listed as polar urals - taimyr central Siberia.
>China shoudl be relabeled as east Asia as it does include some information
>from Japan and the Tibetan Plateau (L. Thompson) and we don't want to get
>into some political to-do by calling Tibet "Chinese".
>that's all I can think of for present, good sailing, tom
>Keith Briffa wrote:
>>Hi all
>>think this is resolved now (virtually) -
>>We use series that total to Tom/Gabi composite , and we can cite this as
>>an example of the scatter of regional records "in a typical
>>reconstruction". This avoids very difficult issue of what is the best way
>>to aggregate certain data sets - we are simply illustrating the point
>>with one published (by then) data set.
>>The issue of the composite is then not an issue either , because it is
>>not a new (unpublished) composite that we were concerned about - though I
>>still believe it is a distraction to put the composite in. It would be
>>best to use data from 800 or 850 at least , and go to 1500 (?) and
>>presumably normalise over the whole period of data shown. OK? Even though
>>you guys all wish to go with the reduced period (ie not up the present) ,
>>but my own instinct is that this might later come back to haunt us - but
>>will take your lead.
>>I agree the look of the Figure should match the others.
>>So, if Tom will send the data sets (his regional curves) , Tim will plot
>>and send back asap for scrutiny. Thanks Tom and thanks for your help
>>with this - further comments on latest version of 6.5 (last 2000 years)
>>still welcome , though will be incorporating a few changes in response to
>>David and Fortunat input , and SH bit (from Ricardo and Ed) still to go
>>in and regional section to be revised (after input from Peck et al.)
>> At 21:42 19/07/2005, Jonathan Overpeck wrote:
>>>Hi Keith and Tim: Just got off the phone with Eystein, and hopefully he
>>>will sleep ok knowing that we have a plan for the MWP fig and Tom...
>>>Please ask questions if we don't cover all the key points, but here's
>>>what we think:
>>>1) the MWP fig should span the MWP only, and should emphasize variation
>>>in regional amplitude (we agree that we must be clear that this fig is
>>>not a reconstruction) - that is, it is best to use time series
>>>representing regions, assuming that the regional series do represent a
>>>region ok with one or more input series. We want to avoid a regional
>>>bias if we can - this is what got us into all the MWP misunderstanding
>>>in the first place, perhaps (e.g., nice MWP in Europe/Atlantic region -
>>>must be global)
>>>2) If you guys could agree on the series and the interval, that'd be
>>>great. We agree it would be good to start before 1000 and end before the
>>>Renaissance (15th century?). If you want more feedback on these issues,
>>>we're happy to provide, but it seems logical that you pick series and
>>>intervals so that each series covers the entire interval selected.
>>>3) Don't use the Chesapeak record - it is likely biased by salinity
>>>4) We'd like Keith and Tim to draft the final figure so that it matches
>>>the look and style of the other two figs they have made. Hope this is
>>>doable. Tom, does Keith have all the data? Thanks for sending if not.
>>>5) We agree that Tom should NOT be a CA given that he was officially one
>>>of the ZOD reviewers. Of course, this doesn't represent a real conflict,
>>>but we need to avoid even the appearance of conflict. We greatly
>>>appreciate all the feedback that Tom is providing! Is this plan ok w/
>>>you Tom? We think you're cool with it, but just want to check one more time.
>>>That... it is. Please let us know if there are any more questions. Keith
>>>- feel free to try and get Eystein on his cell doing your work hours if
>>>you want quick feedback. Or we can do this by email - he's not in a very
>>>email friendly place right now, but the fishing appears to be ok.
>>>Again, thanks to you both for all the discussion and thought that has
>>>gone into this figure.
>>>Best, peck
>>>Jonathan T. Overpeck
>>>Director, Institute for the Study of Planet Earth
>>>Professor, Department of Geosciences
>>>Professor, Department of Atmospheric Sciences
>>>Mail and Fedex Address:
>>>Institute for the Study of Planet Earth
>>>715 N. Park Ave. 2nd Floor
>>>University of Arizona
>>>Tucson, AZ 85721
>>>direct tel: +1 520 622-9065
>>>fax: +1 520 792-8795
>>Professor Keith Briffa,
>>Climatic Research Unit
>>University of East Anglia
>>Norwich, NR4 7TJ, U.K.
>>Phone: +44-1603-593909
>>Fax: +44-1603-507784

Dr Timothy J Osborn
Climatic Research Unit
School of Environmental Sciences, University of East Anglia
Norwich NR4 7TJ, UK

phone: +44 1603 592089
fax: +44 1603 507784


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