Hans
just too bogged down with stuff to even read their crap - but I have no intention of
withholding anything. Will supply the stuff when I get five minutes!! no idea what the
so-called update stuff is about
Keith
At 11:19 05/08/2006, you wrote:
Dear Keith,
I read this comment on the prometheus-weblog of Roger Pielke jr:
"Ask Briffa for site identifications for Briffa et al 2001? While you're at it, ask him
for the measurement data for Taimyr, Tornetrask update and Yamal? Ask Briffa why he
didn't publish the updated Polar Urals results."
The background of this inquiry seems to be the replicability of your studies. I think
this is a reasonable request, but some people claim that you would "stonewall" any such
attempts. ("The issue of data access was discussed in the dendro conference in Beijing -
some people suggesting that withholding data was giving the trade a black eye. Industry
leaders, such as presumably Briffa, said that they were going to continue
stonewalling.") I can not believe this claim, and I would greatly appreciate if you
would help me to diffuse any such suspicions.
As you possibly have heard, I had a chance to hear a lot what is said on Capitol Hill
(see attachment) - and I am concerned if we do not apply a truly open data and
algorithm-policy, our credibility will be severly damaged, not only in the US but also
in Europe. "Open" means also to provide data to groups which are hostile to our work -
we have done so with our ECHO-G data, which resulted in two hostile comments in
"science", which were, however, useful as they helped to clarify some issues.
All the best,
Hans
--
Hans von Storch
hvonstorch@web.de; skype: hvonstorch
presently: Kaspervej 2, 4673 Rödvig, Danmark
+45 5650 6760
------------------------------
Institute for Coastal Research
GKSS Research Center
Max-Planck-Strassse 1
21502 Geesthacht
Germany
[1]
ph +49 171 212 2046
fx: +49 4152 87 4 1831
--
Professor Keith Briffa,
Climatic Research Unit
University of East Anglia
Norwich, NR4 7TJ, U.K.
Phone: +44-1603-593909
Fax: +44-1603-507784
[2]
References
1.
2.


Dear Keith,
I think we have to take this talking and questioning seriously. what we do is important and we have to allow for replication. when we were confronted with such requests concering the ERIK-simulations, we were initially  reluctant, but now we gove teh data to verybpody. Got us two critical comments in "science" but I think it was worth it.
Do you mind if I publish your response? Would be the prometheus weblog.
I could ask what is meant with "update" - I do know not what is meant; I had just quoted a request which I find in principle not unreasonable - and I am happy to hear that you in principle agree.
Regards,
Hans
> -----Ursprüngliche Nachricht-----
> Von: Keith Briffa
> Gesendet: 11.08.06 18:57:25
> An: Hans von Storch
> Betreff: Re: open data access?
> Hans
> just too bogged down with stuff to even read
> their crap - but I have no intention of
> withholding anything. Will supply the stuff when
> I get five minutes!! no idea what the so-called update stuff is about
> Keith
>
> At 11:19 05/08/2006, you wrote:
> >Dear Keith,
> >
> >I read this comment on the prometheus-weblog of Roger Pielke jr:
> >
> >"Ask Briffa for site identifications for Briffa
> >et al 2001? While you're at it, ask him for the
> >measurement data for Taimyr, Tornetrask update
> >and Yamal? Ask Briffa why he didn't publish the updated Polar Urals results."
> >
> >The background of this inquiry seems to be the
> >replicability of your studies. I think this is a
> >reasonable request, but some people claim that
> >you would "stonewall" any such attempts. ("The
> >issue of data access was discussed in the dendro
> >conference in Beijing - some people suggesting
> >that withholding data was giving the trade a
> >black eye. Industry leaders, such as presumably
> >Briffa, said that they were going to continue
> >stonewalling.") I can not believe this claim,
> >and I would greatly appreciate if you would help
> >me to diffuse any such suspicions.
> >
> >As you possibly have heard, I had a chance to
> >hear a lot what is said on Capitol Hill (see
> >attachment) - and I am concerned if we do not
> >apply a truly open data and algorithm-policy,
> >our credibility will be severly damaged, not
> >only in the US but also in Europe. "Open" means
> >also to provide data to groups which are hostile
> >to our work - we have done so with our ECHO-G
> >data, which resulted in two hostile comments in
> >"science", which were, however, useful as they helped to clarify some issues.
> >
> >All the best,
> >Hans
> >
> >
> >--
> >Hans von Storch
> >hvonstorch@web.de; skype: hvonstorch
> >
> >presently: Kaspervej 2, 4673 Rödvig, Danmark
> >+45 5650 6760
> >------------------------------
> >
> >Institute for Coastal Research
> >GKSS Research Center
> >Max-Planck-Strassse 1
> >21502 Geesthacht
> >Germany
> >
> >ph +49 171 212 2046
> >fx: +49 4152 87 4 1831
> >
> >
> >
>
> --
> Professor Keith Briffa,
> Climatic Research Unit
> University of East Anglia
> Norwich, NR4 7TJ, U.K.
>
> Phone: +44-1603-593909
> Fax: +44-1603-507784
>
>
>
--
Hans von Storch
hvonstorch@web.de; skype: hvonstorch
presently: Kaspervej 2, 4673 Rödvig, Danmark
+45 5650 6760
------------------------------
Institute for Coastal Research
GKSS Research Center
Max-Planck-Strassse 1
21502 Geesthacht
Germany

ph +49 171 212 2046
fx: +49 4152 87 4 1831
Attachment Converted: "c:\eudora\attach\smime2.p7s"


Hi Keith:
Thanks so much for the chance to look over this section.  I think the long section you added on pp 6-5 and 6-6 reads well, and makes good sense according to what I know.  Indeed, reading the whole section is a good review for me!
I suggested addition of a phrase in lines 32-33 on page 6-3 regarding MM 2003 and analysis of it by Wahl-Ammann 2006.  I also suggest a (logically useful) change from singular to plural in line 42 of that page. The changes are in RED/BOLD font.
[I should note that AW 2006 is still in "in press" status, and its exact publication date will be affected by publication of an editorial designed to go with it that Caspar and I are submitting this weekend.  Thus I cannot say it is certain this article will come out in 2006, but its final acceptance for publication as of 2/28/06 remains completely solid.]
Also, I added the full information for the Wahl-Ritson-Ammann 2006 Science article in the references section, also in RED/BOLD font.
By the way, is the "AJS" NCAR-CSM model in Fig. 6-13 the one Caspar did?  I couldn't tell this for sure from the information in the text.  If it is, perfect.  If not, is there a way to include his millenium run?
Thanks to you and all the authors for you painstaking work.
Peace, Gene
Dr. Eugene R. Wahl
Asst. Professor of Environmental Studies
Alfred University
607-871-2604
1 Saxon Drive
Alfred, NY 14802
________________________________
From: Keith Briffa
Sent: Mon 7/31/2006 10:29 AM
To: Wahl, Eugene R
Subject: RE: confidential
First Gene - let me say that I never intended that you should spend
so much time on this - though I really appreciate your take on these
points. The one you highlight here - correctly warns me that in
succumbing to the temptation to be lazy in the sense of the brief
answer that I have provided  - I do give an implied endorsement of
the sense of the whole comment. This is not, of course what I
intended. I simply meant to agree that some reference to the
"divergence" issue was necessitated . I will revise the reply to say
briefly that I do not agree with the interpretation of the reviewer.
I am attaching what I have done (see blue highlighting) to the
section in response to comments (including the addition of the needed
extra section on the "tree-ring issues" called for by several
people). I have had no feedback yet on this as it has not been
generally circulated , but thought you might like to see it. PLEASE
REMEMBER that this is "for your eyes only " . Please do NOT feel that
I am asking /expecting you to go through this in any detail - but
given  the  trouble  you have taken,I thought it reasonable to give
you a private look. Cheers
Keith
At 07:16 27/07/2006, you wrote:
>Hi Keith:
>
>Here is the text with my comments.  I will go over the "stolen"
>parts (highlighted in blue outline) for a final time tomorrow
>morning, but I wanted to get this to you ASAP.  The main new point I
>have to make is added in bold/blue font on pp. 101-103.  I question
>the way the response to the comment there is currently worded, as it
>seems to imply that the divergence issue really does invalidate any
>dendro-based reconstructions before about 1850--which I imagine is
>not what you would like to say.  I give a series of arguments
>against this as a general conclusion.  Maybe I got over-bold in
>doing so, as in my point (1) I'm examining issues that are at the
>very core of your expertise!  Excuse me that one, but I decided to
>jump in anyway.  Let me know if I got it wrong in any way!
>
>There are other quite minor suggestions (mostly focused on
>referencing other responses in a few places) that are also in
>bold/blue.  These go on into the "120's" in terms of page numbers.
>
>This is really a lot of work you've taken on, and I REALLY
>appreciate what you and the others are doing!
>
>[I've also been a lot involved with helping to get a person from the
>Pew Center for Global Climate Change ready to testify in front of
>the House Energy and Environment Committee tomorrow.  That is why I
>couldn't get this done and sent to you earlier today.  Send Mike
>Mann and Jay Gulledge (Pew Center) all good thoughts for strength and clarity.]
>
>
>NB -- "r" towards the end of the filename stands for my middle initial.
>
>
>Peace, Gene
>Dr. Eugene R. Wahl
>Asst. Professor of Environmental Studies
>Alfred University
>
>607-871-2604
>1 Saxon Drive
>Alfred, NY 14802
>
>________________________________
>
>From: Keith Briffa
>Sent: Mon 7/24/2006 3:16 PM
>To: Wahl, Eugene R
>Subject: RE: confidential
>
>
>
>
>
>Gene
>here is where I am up to now with my responses (still a load to do) -
>you can see that I have "borrowed (stolen)" from 2 of your responses
>in a significant degree - please assure me that this OK (and will not
>later be obvious) hopefully.
>You will get the whole text(confidentially again ) soon. You could
>also see that I hope to be fair to Mike - but he can be a little
>unbalanced in his remarks sometime - and I have had to disagree with
>his interpretations of some issues also.
>
>Please do not pass these on to anyone at all.
>Keith
>
>
>
>Will pass all comments to you before they are fixed in stone- nothing
>from review article will be mentioned.
>Really grateful to you - thanks
>Keith
>
>At 05:08 22/07/2006, you wrote:
> >Hi Keith:
> >
> >Glad to help. (!)
> >
> >If I could get a chance to look over the sections of my text you
> >would post to the comments before you do, I would appreciate it.  If
> >this is a burden/problem let me know and we'll work it out.
> >
> >If it is anything from the Wahl-Ammann paper, of course that is fine
> >to use at once since it is publicly available.  There will only be
> >exceedingly minor/few changes in the galleys, including a footnote
> >pointing to the extended RE benchmarking analysis contained in the
> >Ammann-Wahl review article.
> >
> >What I am concerned about for the time being is that nothing in the
> >review article shows up anywhere.  It is just going in, and
> >confidentiality is important.  The only exception to this are the
> >points I make in my blue comments in the big review file on page
> >104, concerning the MM way of benchmarking the RE statistic.  Those
> >comments are fine to repeat at this point.  [Please excuse my
> >hesitance in this way.]
> >
> >Actually, all the other blue comments I made in the big review file
> >are also fine to use at once.
> >
> >
> >Again, if this request is in any way a problem, let me know and
> >we'll figure out something.
> >
> >
> >Peace, Gene
> >Dr. Eugene R. Wahl
> >Asst. Professor of Environmental Studies
> >Alfred University
> >
> >________________________________
> >
> >From: Keith Briffa
> >Sent: Fri 7/21/2006 2:00 PM
> >To: Wahl, Eugene R
> >Subject: RE: confidential
> >
> >Gene
> >your comments have been really useful and reassuring that I am not
> >doing MM a disservice.  I will use some sections of your text in my
> >comments that will be eventually archived so hope this is ok with
> >you. I will keep the section in the chapter very brief - but will
> >cite all the papers to avoid claims of bias. I really would like to
> >discuss the whole issue of the reconstruction differences at a later
> >, less stressful time. I completely accept the arguments about the
> >limitation in the r2  and the value of capturing longer-term variance
> >. I think I will have to stop now as the temp and humidity are killing here.
> >
> >Thanks a lot again
> >
> >Keith
> >
> >At 18:39 21/07/2006, you wrote:
> > >Hi Keith:
> > >
> > >I'm sorry that there is a bit to digest...although I know it is just
> > >a result of the nature of things.
> > >
> > >By the way, copied below is a synopsis that I sent this morning to a
> > >person in DC who is working on all this with regard to the House of
> > >Representative hearings.  Evidently, there is to be at least one
> > >more hearing next week, and Mike Mann will go.  The person I sent
> > >this to is trying to understand the importance of the proxy PC
> > >issues --especially how, no matter what way the PC extraction is
> > >done, the reconstructions converge if the structures actually
> > >present in the data are not tossed out by truncating the number
> > >retained PCs at a too low level.  What I've copied is this
> > >synopsis.  I think it is straightforward -- maybe a bit dense, but
> > >at least brief.
> > >
> > >Also, let me know if I can help on the issue of RE vs r^2.  I could
> > >write a few brief sentences as something for you to look at if you
> > >would like.  Wahl-Ammann show very clearly that there is objectively
> > >demonstrated skill at the low-frequency level of the verification
> > >period mean for all the MBH segments, although the earlier MBH
> > >segments do have really low r^2 values (indicating very little skill
> > >at the interannual level).  Our argument that to throw out the
> > >reconstruction completely based on the fastest varying frequency,
> > >when it has objectively demonstrable meaning at lower frequencies,
> > >is to me quite reasonable.  That it is some how entirely ad hoc, as
> > >McIntyre claims in one (more?) of his comments, is neither logical
> > >nor factual in my perspective.  The idea of frequency dependent
> > >skill/non-skill is not new to the literature, and the independent
> > >re-reviewer that Steve Schneider had look over Wahl-Ammann said s/he
> > >had experienced this issue in his/her work.      G.
> > >
> > >
> > >****************************** COPIED TEXT ******************************
> > >
> > >What it boils down to in the end is as follows:
> > >
> > >1)  The different reference periods used to calculate proxy PCs from
> > >N. America (calibration only for MBH, full period for MM) only have
> > >the effect of re-arranging how the hockey stick shape appears across
> > >the rank ordering of PCs.  In MBH it is concentrated in PC1.  In the
> > >full-period method, it is spread over PCs 1 and 2.  If one adds PCs
> > >1 and 2 (either arithmetically or as vectors) from either
> > >convention, you get an essentially IDENTICAL time series, only the
> > >amplitudes are a bit different.   [Note that the input data were
> > >centered AND standardized before being put into the PC calculation
> > >algorithm.  This is important, as shown below.]
> > >          WHEN ACTUALLY USED IN THE RECONSTRUCTION, THE DIFFERENCE
> > > IS MINISCULE -- MBH is colder over 1400-1449 by 0.05 degrees!
> > >
> > >2)  IF the data are centered but NOT standardized and are input into
> > >in a PCA algorithm using the variance-covariance matrix and not the
> > >correlation matrix (the way MM did it), then the hockey stick shape
> > >shows up in PC4.  MM in fact reported this first in their 2005
> > >Energy and Environment article.  In effect, the first two PCs are
> > >ARE ACTING TO DO THE STANDARDIZING OF THE DATA not done as a
> > >pre-processing step.  [When the correlation matrix is used instead
> > >in the PCA algorithm, then the standardization is in effect done by
> > >the algorithm, because all the correlations are "standardized" by
> > >construction--they all range between 0 and 1.]
> > >          When 4 PCs from this calculation method are used rather
> > > than 2 PCs calculated as above, then the RECONSTRUCTION CONVERGES
> > > TO THE SAME AS ABOVE.
> > >
> > >3)  Thus, all the different "flavors" for PC extraction have
> > >essentially no effect on reconstruction when one does the exercise
> > >of adding PCs sequentially from 2 to 5 for any flavor.  In the case
> > >of (1), the reconstructions converge by the second PC.  In the case
> > >of (2), they converge by PC4.  They don't change with higher order
> > PCs added.
> > >         THIS SHOULD BE EXPECTED FROM FIRST PRINCIPLES.  That is,
> > > the same underlying information is  there in all cases, it is only
> > > how the structures present in these data are spread across the rank
> > > order of PCs, as explained.  The simple exercise of taking the
> > > reconstructions to convergence across the number of PCs used shows
> > > this clearly.
> > >
> > >4)  In fact, MM essentially say all this in the 2005 EE
> > >article--INCLUDING ABOUT THE RECONSTRUCTION RESULTS -- but they
> > >strongly claim that the movement of the hockey stick shape to the
> > >4th PC shows it is not a leading pattern of variance as MBH claim,
> > >and thus should not be used.  This might be logical if their
> > >analysis was an apples-apples comparison, but it is not, due to the
> > >PCA method they use and applying it on NON-standardized data.
> > >             THESE TWO DIFFERENCES (which one can only fully get
> > > from their actual code, not in the articles published) DRIVE THEIR
> > > ENTIRE ARGUMENT ON THIS PARTICULAR ISSUE.  What they do not say is
> > > that convergence to something like the MBH result is expectable,
> > > and indeed MUST happen given the data used, because the hockey
> > > stick shape is actually IN the data, it is NOT an artifact of PC
> > > calculation procedure.
> > >
> > >
> > >5)  FINALLY, note that all of this rests on the foundation that
> > >keeping the bristlecone pine records in the data is appropriate,
> > >which Caspar and I find can be reasonable presumption.  If one
> > >believes that the bristlecone data should be removed, then the
> > >1400-1449 reconstruction does not pass verification testing with the
> > >RE statistic, and the MBH reconstruction should commence from 1450 on out.
> > >
> > >Although there are a number of reasons to keep the bristlecone data
> > >in, maybe the most compelling reason they are a NON-ISSUE is that,
> > >over the common period of overlap (1450-1980), the reconstruction
> > >based on using them from 1400-1980 is very close to the
> > >reconstruction based on omitting them from 1450-1980.  Since the
> > >issues about the bristlecone response to climate are primarily about
> > >1850 onwards, especially 1900 onwards [KEITH -- PLEASE LET ME KNOW
> > >IF I AM NOT ACCURATE IN THIS], there is no reason to expect that
> > >their behavior during 1400-1449 is in any way anomalous to their
> > >behavior from 1450-1850.  Thus, THERE IS NO REASON TO THINK THAT THE
> > >BRISTLECONES ARE SOMEHOW MAKING THE 1400-1449 SEGMENT OF THE MBH
> > >RECONSTRUCTION BE INAPPROPRIATELY SKEWED.
> > >
> > >
> > >****************************** END OF COPIED TEXT *******************
> > >
> > >Peace, Gene
> > >Dr. Eugene R. Wahl
> > >Asst. Professor of Environmental Studies
> > >Alfred University
> > >
> > >607-871-2604
> > >1 Saxon Drive
> > >Alfred, NY 14802
> > >
> > >________________________________
> > >
> > >From: Keith Briffa
> > >Sent: Fri 7/21/2006 4:51 AM
> > >To: Wahl, Eugene R
> > >Subject: RE: confidential
> > >
> > >
> > >
> > >Gene
> > >thanks a lot for this  - I need to digest and I will come back to you.
> > >
> > >thanks again
> > >Keith
> >
> >--
> >Professor Keith Briffa,
> >Climatic Research Unit
> >University of East Anglia
> >Norwich, NR4 7TJ, U.K.
> >
> >Phone: +44-1603-593909
> >Fax: +44-1603-507784
> >
> >
>
>--
>Professor Keith Briffa,
>Climatic Research Unit
>University of East Anglia
>Norwich, NR4 7TJ, U.K.
>
>Phone: +44-1603-593909
>Fax: +44-1603-507784
>
>
>
>
--
Professor Keith Briffa,
Climatic Research Unit
University of East Anglia
Norwich, NR4 7TJ, U.K.
Phone: +44-1603-593909
Fax: +44-1603-507784

Attachment Converted: "c:\eudora\attach\Ch06_SOD_Text_TSU_FINAL_2000_25jul06KRB-FJ-RV_ERW_suggestions.doc"


Hi Mel - thanks. Since chap 6 CA Tim Osborn is an author on this paper, I'm sure he and
Keith have made the right call.
Thanks again, Peck
X-Sieve: CMU Sieve 2.2
Date: Thu, 10 Aug 2006 09:44:03 -0600
From: IPCC-WG1
X-Accept-Language: en-us, en
To: Jonathan Overpeck
,
Eystein Jansen
Subject: Tett et al. paper
Hi Peck and Eystein,
Although the deadline for additional accepted papers has now passed, this submission
comes from a CLA (Gabi Hegerl) so am forwarding on. Official acceptance of the Tett et
al. paper was 2 June. My understanding is that you already have a copy, but will forward
the copy sent in by Simon just in case.
Cheers,
Mel
--
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
IPCC WGI TSU
NOAA Chemical Sciences Division
325 Broadway DSRC CSD08
Boulder, CO 80305, USA
Phone: +1 303 497 7072
Fax: +1 303 497 5686/5628
Email: [1]ipcc-wg1@al.noaa.gov
--
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

Attachment Converted: "c:\eudora\attach\Tett_etal.pdf"
References
1. mailto:ipcc-wg1@al.noaa.gov


ï»¿
Due to the ongoing debate, this has turned  an even more difficult manuscript. In general, I think Martin did a very good job in the review of the literature. Concerning the new reconstructions and the evaluation of McIntyre work, I would not fully agree with some of the conclusions, which I thin do not follow from the material presented in the text. I have some remarks on this which you may consider useful. But I think that I am not the one that should give the manuscript the final shape, as Martin is the person in charge of the project. Please, consider the following comments as suggestions.
eduardo
Consensus: I would tend to avoid the word 'consensus', since it is not a well defined concept.
Depending on the meaning of consensus, each would agree with it to a certain degree. I would prefer to refer to a particular  IPCC conclusion, or something similar. I think this review of the literature is very well written and informative, but I am not sure that  each one of us will agree with each one of the concussions of each of the papers.
Page 12, section 2.8. I think the text is somewhat vague here, and it could be misunderstood.
Mann et al (2005) tested the RegEM method, not the original MBH98 method. It is true that applied to the
real proxies both methods, according to Mann, yield very similar results. But strictly speaking , Mann did not test the MBH98 method in the CSM simulation. The MBH98 method is thereby only by implication
I tested the the sensitivity of the MBH98, and not of RegEM,  to the length of the calibration period. It may be the RegEM is less sensitive or not at all. Figure 4 and 5, if I understood well, support this dependency of MBH to the calibration period.  Am I correct to interpret the large differences between the original MBH reconstruction (dashed red) and the black curve as due to the different calibration period (1901-1980 versus 1856-1980) and to the use of the leading PC or NHT as calibration target? At least in the period prior to 1600  I think these are the only methodological differences between both curves (?).
My interpretation of this figure is also somewhat different. If the final reconstructions differs so strongly by using a longer calibration period (in general yielding stronger decadal variability in the reconstruction) I would tend to think that the method based on these proxies is quite unstable. What would happen if the calibration period could have been extended to 1800, for instance?.
Page 15: top. The role of forcing on the global or NH T is also recognized in the correlation between the NHT simulated by ECHO-G and CSM for the millennium. For the case of  a second ECHO-G simulation /Gonzalez-Rouco et al.) the agreement is very close at 30-year timescale.
Section 3, beginning.
In my opinion, MM05 stress the inadequacies and uncertainties in the MBH work, but they not put forward their own reconstruction implying a warmer-than-today MWP.  They believe that this is true, but in their works so far, at least to my knowledge, they do not assert that the MWP was warmer than present, only that the uncertainties are too large for such a claim.
Section 3: Consensus. This paragraph may be problematic. Again what is the consensus? If we look at the recent NAS report, which again not every one would agree with, the 'consensus' is reduced to the past 400 years in comparison to IPCC, leaving ample space for speculation before this period. Does the NAS report belong to the consensus?  perhaps partially, but I am not sure to what extent.
Section 3, discussion of MM05 and hockey-stick index. I have here a certain level of disagreement  with these paragraphs. The issue raised by MM05 would be  that the de-centering of the proxies prior to the calculations of the principal components tends to produce hockey-stick-shaped leading PC.  I think this effect is true, at least with spatially uncorrelated red-noise series . It can be easily verified and it has been recognized in the NAS, the Wegman report and  by Francis Zwiers. To be fair, following this issue is the problem of the truncation- just to keep the leading PC or further Pcs down the hiercharchy, and if this is done, the final differences could be probably  minor. in the final reconstructions.  But the paragraph implies, in my opinion, that this criticism  by MM05 has no grounds, which as I said is problematic and could open the manuscript with criticisms based on these recent reports.
I think that the calculation shown in Figure 3 is very useful, as it boils down to the issue raised by MM05: how relevant is the de-centering and standardization with real proxies?. Apparently, I get a different message from Figure3 (although I may have misinterpreted the text). I see quite large differences in the 20th century between the original MBH leading PC and the 'correct' calculation (whole period centering and standarization,blue line). Only the original MBH PC shows a positive trend in the 20th century. The blue lines seems even to show a negative trend or no trend at all. If this PCs were to be used in the MBH regression model (with trend included in the calibration) the results could be quite different. I would tend to think that this figure actually supports the MM05 criticism, since the hockey-stick shape of the leading PC disappears.
Section 3, end, bristlecone pines. I am also worried by this paragraph. The recent NAS report clearly states that the bristlecone pines should not be used for reconstructions in view of their potential problems. They cite previous analysis on this issue. I think that to refer to just one study  indicating no fertilization effect could not be enough. However, I am not a dendroclimatologist. This could open the door to potential problems.
Section 4 , end. years 1997 and onwards were the warmest in the millennium. I see here also potential problems with this claim, and I do not see  the need to make our lives more complicated. The NAS report expressed that the uncertainties are too large for this type of conclusion and certainly this conclusion  would attract some attention from the reader. I see two lines of criticism on this: one is that the standard errors have been calculated with the calibration residuals and these are an underestimation of the true uncertainties. A reviewer may require that the uncertainty range be calculated by cross-calibration or bootstraping. In the case of CVM perhaps this effect is not very important, as there is just one free parameter, but in the case of inverse regression there are much many more free parameters and the true uncertainties can be quite different from those estimated from the calibration residuals. This potential criticism could be exacerbated by the fact that the new reconstruction has not been tested in a validation period.
The other line of criticism could be  that the calibration period has been, as in all reconstructions, a priori truncated -data after 1980 are not considered as the proxies are known to not follow the temperature. Strictly speaking this truncation can be only justified by a credible physical explanation about the cause of this divergence. Statistically, I think it is not correct to a priori ignore some data because they do not fit. If one does so, I think the uncertainty range should be enlarged to encompass the possibility that this divergence could have happened in the past, i.e. an additional standard deviation of the instrumental NH T in the period 1980-2000 (or perhaps more correct, the square root of the sum of the error variance and the NHT variance in 1980-2000). Alternatively, one could include the period 1980-2000 in the calibration and due to the divergence the standard errors would grow, but perhaps this is practically not possible as the proxy time series may not have been archived for the last 20 years.
Section 5, conclusions.
I share the worry of Anders Moberg about the wording 'serious flaws' in the analysis of MM05.  This sentence would be based on Figure 3, if I understood properly, but as I said I think Figures 3 actually does not support this conclusion.
Finally, I think it would strategically better to avoid conflicts on the particular point of whether some particular year was the warmest of the millennium or not, and to stress the fact that all reconstructions, also the new ones presented in the manuscript (with one exception) show MWP temperatures lower than late 20th century temperatures.
Another conclusion could be, in my view, that the average temperature in the cold centuries in the millennium seems to be still quite uncertain. The new reconstructions, or the calculation of the leading PCs of the proxies, seem to be still quite sensitive to particular choices in the statistical set-up.


HI Keith,
If the offer still stands, we wanted to get from you the ECHO-G surface
temperature field, so we can do some tests of RegEM with this. So far
we've only tested on CSM 1.4 and it would be nice to test this on on
ECHO-G, especially since other groups apparently now also have the
ECHO-G outpout (e.g. Mark Cane's group and Francis Zwiers' group).
Thanks in advance for any help w/ this,
mike
--
Michael E. Mann
Associate Professor
Director, Earth System Science Center (ESSC)
Department of Meteorology              Phone: (814) 863-4075
503 Walker Building                    FAX:   (814) 865-3663
The Pennsylvania State University      email:  mann@psu.edu
University Park, PA 16802-5013


Hi Keith,
John should have the latest versions of the comments file and the chapter text, i.e. the
ones that went out for LA review this summer. I believe he is after some more specific
answers in the comments and not so much changes to the text, and has selected the
bristlecone issue, the divergency issue and the verification and robustness issues. If you
are unsure what comments or tetx he refers to, I think the best thing is for to ask John
for the specific comments he thinks are not adequate, or the specific lines of text which
he suggests changed. It seems he needs some reassurance rather than you writing much new in
terms of comments and text, so the best would be to talk to him and ask what he needs you
to do to the documents.
Best wishes,
Eystein
Envelope-to: Eystein.Jansen@geo.uib.no
Date: Wed, 30 Aug 2006 15:31:12 +0100
To: Eystein Jansen
From: Keith Briffa
Subject: Fwd: Chpt 6 - last 1000 yrs
X-UEA-Spam-Score: -101.6
X-UEA-Spam-Level: ---------------------------------------------------
X-UEA-Spam-Flag: NO
X-checked-clean: by exiscan on noralf
X-UiB-SpamFlag: NO UIB: -13.8 hits, 8.0 required
X-UiB-SpamReport: spamassassin found;
-15 From is listed in 'whitelist_SA'
0.1 BODY: Message is 30% to 40% HTML
0.0 BODY: HTML included in message
1.1 BODY: Message only has text/html MIME parts
Eystein
John sent these remarks - have not talked with him yet - but not sure what is now
required
Keith
X-IronPort-AV: i="4.08,132,1154908800";
d="scan'208,217"; a="17827006:sNHT58118592"
Subject: Chpt 6 - last 1000 yrs
Date: Wed, 16 Aug 2006 16:14:52 +0100
X-MS-Has-Attach:
X-MS-TNEF-Correlator:
Thread-Topic: Chpt 6 - last 1000 yrs
Thread-Index: AcbBRrj0FPNJH9bQTyCswuNw7Ln3bw==
From: "Mitchell, John FB \(Chief Scientist\)"
To: "Keith Briffa"
Cc: "Mitchell, John FB \(Chief Scientist\)"
X-UEA-Spam-Score: 2.1
X-UEA-Spam-Level: ++
X-UEA-Spam-Flag: NO
Hi Keith
I have tried to cindense what I think the main issues for the and what the response is
below. The weakest area seems to be statistical significance and by implication the
likely/ very likely statements. I can't think of any easy solution - in the TAR for
detection and attribution we used 95% limits on stats tests and them downrated them to
allow for other uncertainties.
I am interested in your comments
John
Issues
1. Reliance on Bristlecone pine -
Response - the issues are in calibration period- they agree with other indicators for
the rest of the record
2. Centring of principle components leads to "hockeysticks"-
Response - this makes only a small difference when standardised data used.
Comment - Would be useful to know which reconstructions do and donot make this
assumption- this could strengthen the response
3. The divergence issue-
Response - it is only apparent in high latitudes, and only with some trees.
Comment- Do we know what happens if we eliminate those records with a divergence
problem. The wider issue is whether or not it is reasonable to extend the
reconstructions outside the calibration range.
4. There are different ways of verifying reconstructions and assigning significance
levels( calibration period or seprate verifying period, different statistics)
Response ?
Comment- it is difficult in the text to gauge how well reconstructions are validated -
eg using the calibration period to estimate errors as opposed to an independent period
clearly makes a difference. This is important where "likely", "very likely"are used-
based on what statistics? I think this is the area where I think the current response is
weakest
5. Robustness- Burger and Cubasch show a wide range of results using different
assumptions-
Response ?
Mann makes a reasoned defence- there are other checks and tests which would rule out
many of the arbitrary assumptions explored by Cubasch and Burger, but this is not clear
in the response to M&M etc
--
Professor Keith Briffa,
Climatic Research Unit
University of East Anglia
Norwich, NR4 7TJ, U.K.
Phone: +44-1603-593909
Fax: +44-1603-507784

--
______________________________________________________________
Eystein Jansen
Professor/Director
Bjerknes Centre for Climate Research and
Dep. of Earth Science, Univ. of Bergen
Allégaten 55
N-5007 Bergen
NORWAY
e-mail: eystein.jansen@geo.uib.no
Phone:    +47-55-583491  -  Home: +47-55-910661
Fax:       +47-55-584330


Jonathan,
I haven't looked at these in great detail, but I
have a problem with Martin making suggestions
about the TSU Exec Summary for chap 6. Weren't
these decided by consensus among the Chap 6
authors? Why does Martin have any say about this?
Clarification is one thing, but some of these
suggestions seem to be 'leading'. I think we
should be very cautious about changing anything
substantive here at the last moment. [This is the
expurgated version of what I really thing.]
David
At 4:55 PM -0600 8/31/06, Jonathan Overpeck wrote:
>Hi all - We need to submit our latest chap 6
>Exec Summary to TSU tomorrow if we can. We can
>still make changes, but I wanted to update with
>Martin's suggestions taken into account. See the
>attached and please comment regarding my strike
>throughs and additions (yellow highlight).
>Martin's comments are in yellowish text, and my
>questions to you (especially FORTUNAT) are
>higlighted in PURPLE.
>
>Please send by tomorrow aft if you can.
>
>Not that I've sent to those I think are on-line
>right now. Will send to the whole team later
>with more edited text.
>
>Thanks, 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
>
>
>
>Attachment converted:
>Toltec:Ch06_FinalDraft_ExecSumV3.doc (WDBN/«IC»)
>(1BEA76C7)
--
///////////////////////////////////////////////////////////////////////////
///////////////////////////////////////////////////////////////////////////


Hi all - today has been a hectic one, with lots of good input from multiple folks. In the
end, we agreed to stick with our existing bullets, which changes only where they would
improve the clarity of what we were saying. Please check the attached - need Fortunat's
detailed look in particular. Changes are all in yellow highlight. Two special issues:
1) There is still concern that this bullet is too vague to be as useful as it could be:
o       It is very likely that the global warming of 4 to 7 °C since the Last Glacial
Maximum (ca. 21,000 years ago) occurred at an average rate about ten times slower than the
warming of the 20th century.
but, perhaps the safest thing would be to leave as is.
2) As for the 1998/2005 warmest in last 1000 years issue, we suggest adding nothing new to
the ES, in line with our chapter policy from Bergen, BUT adding something in the chapter
along the lines of: " There is currently insufficient knowledge to form a consensus on the
issue of how the warmth of individual years of the last 100 years compare with individual
years of the last 1000 years" Keith, would you like to make a suggestion on the wording and
placement?
The reasoning expressed by Stefan on this issue is undoubtedly shared by others outside our
team, and perhaps a paper be written on this key topic to help the community reach better
consensus.
Thanks for your continued dialog and work! Have a good weekend.
best, Peck and Eystein
dear All, thanks for being alert.
I think we have an agreement that Martin´s comments are useful, but that we should
change only those sentences where they clarify. Otherwise i agree with Stefan and
Keith´s statements below.
Eystein
At 15:45 +0100 01-09-06, Keith Briffa wrote:
I forgot to say that I too disagree with removing the first sentence re simulations
being consistent with reconstructed NH temps. As Sefan says we need the context , and
our results are independent of Chapter 9 in this regard.
Keith
At 15:37 01/09/2006, Stefan Rahmstorf wrote:
Hi Peck,
Martin as in Manning? I have found his feedback very useful so far, so we should
definitely look at what he suggests - he mostly tends to look for whether our sentences
are clear. Obviously, he cannot suggest real changes in meaning, only issues of clarity,
but the latter I would take very seriously. Mostly I find his small rewordings good, I
comment on the larger points and exceptions below.
- I am against deleting the bullet on speed of deglacial change. This point is extremely
effective. Just two days ago an oil industry person told me that there have been big
natural climate changes like ice ages in the past, hence we need not worry. I responded
that the biggest warming in recent climate history was the end of the last Ice Age - but
that warming by about 5 ºC took about 5,000 years, not a hundred. "Oh" he said, "Really
so long? I didn't know that." I think it is a very important point, we need to make it.
Maybe not in term of "average rate", may we should just say: the warming of 4-7 ºC took
about 5,000 years, as compared to a future change of up to the same magnitude within a
century.
- Next ice age bullet in 30k seems fine to me.
- exceptional warmth: the SPM said:
20th C T increase likely the largest in a millennium - that is strengthened (perhaps
very likely now?)
1990s likely the warmest decade in a millennium - that again is strengthened
1998 likely the warmest year - I'd say this is unchanged (except for 2005 challenging
it), likely is only 66%! Even though the annual proxy data may be uncertain, as a
physicist I would find it unlikely that there is a mechanism to cause a big warm outlier
year that beats 1998 from a much cooler background state. How would that work - where
would the heat come from?
So in my view we could actually say that these past SPM statements held up or were
strengthened - but in fact I also like the bullet as it is.
- Paleoclimate model simulations are broadly consistent with the reconstructed NH
temperatures over the past 1000 years. The rise in surface temperatures since 1950 very
likely cannot be reproduced without including anthropogenic greenhouse gases in the
model forcings, and it is very unlikely that this warming was merely a recovery from the
pre-20th century cold period.
On this I disagree with deleting the first sentence, as the second one needs it to
follow logically. And why should the paleo chapter suddenly make a statement on
post-1950 warming, if it is not in the context of the past millennium?
Cheers, Stefan
--
To reach me directly please use:
rahmstorf@ozean-klima.de
(My former addresses @pik-potsdam.de are read by my assistant Brigitta.)
Stefan Rahmstorf
www.ozean-klima.de
www.realclimate.org
--
Professor Keith Briffa,
Climatic Research Unit
University of East Anglia
Norwich, NR4 7TJ, U.K.
Phone: +44-1603-593909
Fax: +44-1603-507784

--
______________________________________________________________
Eystein Jansen
Professor/Director
Bjerknes Centre for Climate Research and
Dep. of Earth Science, Univ. of Bergen
Allégaten 55
N-5007 Bergen
NORWAY
e-mail: eystein.jansen@geo.uib.no
Phone:    +47-55-583491  -  Home: +47-55-910661
Fax:       +47-55-584330
--
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

Attachment Converted: "c:\eudora\attach\Ch06_FinalDraft_ExecSumV4.doc"


Keith, Stefan
Its not my role as review editor to tell you what to write, just to make sure you have
responded to the reviewers comments. For what its worth,
I did find Keith's text quite involved.  However, you do need to respond the the reviewers
comments on Burger etc - if the flaws in von Storch paper cast doubt on the subsequent
papers, then why not include a sentence in the chapter that says so, and list just the key
papers affected.
I hope this helps
john
Professor John Mitchell OBE FRS Chief Scientist,
Met Office FitzRoy Road  Exeter  EX1 3PB  United Kingdom
Tel. +44(0)1392884604  Fax:+44 (0) 870 9005050
E-mail: john.f.mitchell@metoffice.gov.uk [1]
______________________________________________________________________________________
From: Stefan Rahmstorf
Sent: 01 September 2006 13:02
To: Keith Briffa
Cc: Mitchell, John FB (Chief Scientist); Eystein Jansen; Jonathan Overpeck
Subject: Re: Fwd: Re: [Wg1-ar4-ch06] NEW DRAFT FOR LA REVIEW
Dear Keith,
you disagree with my proposed revision of the paragraph re. the Von Storch papers, but you
do not give any reasons or arguments for that. I think there are some good reasons to
shorten this discussion and to clarify it, and I would welcome to hear your reasons against
it.
Firstly, I think your original discussion was too long and complex to understand for
non-specialists, and, at this level of detail, not policy-relevant. It took up a
disproportionate amount of space for what we can learn from it.
Secondly, I don't think we need to cite all those Storch-spinoff papers by Bürger/Cubasch.
Most people whose judgement I value (e.g., David Ritson, who I think has no vested interest
but a very detailed knowledge of the issue) think these papers are irrelevant at best and
misleading at worst (he actually has used stronger wording). You may also have seen that
the latest in this series, making similar points, is highly criticised by anonymous
reviewers on the open discussion site of the journal Climate of the Past, where one
reviewer (this is not the even more scathing review by Mann) recommends rejection of the
Bürger/Cubasch paper because of "numerous errors and inaccuracies in the use of statistical
concepts and methods".
Third, if we cite Von Storch et al. 2004 we need to be very clear that a number of key
statements are simply incorrect, which is a fact that is not in dispute and documented in
the literature. They implemented the Mann et al. method incorrectly, and it is at least
unclear whether in their follow-up paper they have now fixed this (Ritson, who discovered
the problem in their original paper in the first place, thinks they still have a problem,
the detrending step was not the only one - and certainly in no paper have VS et al. shown
any test that verifies their algorithm). Also, they were hiding a major artificial climate
drift (which they must have known about, and which makes up half of their climate signal) -
it is at least unclear whether you can expect a proxy method based on physical patterns of
climate variability to reconstruct an unphysical drift, which has a completely different
pattern. I simply think that because of this flaw, we cannot trust or cite any results from
this particular ECHO-G run, which also affects several of the Bürger/Cubasch papers using
the same data set. Given that the VS04 paper was used in the US Senate and other
high-profile fora to discredit IPCC, I think it is imperative that we clarify this and
leave our readers in no doubt about the fact that the VS04 results have proven to be
incorrect in a major way.
I am aware that you authored a favorable Science Perspective on the VS04 paper at the time,
but you could not have known of those errors back then, and for a long time I thought
myself that it was a valid paper. Therefore, if we state clearly in our chapter what is
wrong with it, I do not think this would be a loss of face for you - quite the contrary. I
also think you have done a brilliant job on the rest of the very difficult discussion of
the past millennium.
Best wishes, Stefan
--
To reach me directly please use: [2]rahmstorf@ozean-klima.de
(My former addresses @pik-potsdam.de are read by my assistant Brigitta.)
Stefan Rahmstorf
[3]www.ozean-klima.de
[4]www.realclimate.org
References
1.
2. mailto:rahmstorf@ozean-klima.de
3.
4.


Tim, thanks a bunch. This all sounds very good. We're finalizing a
pseudoproxy paper for JGR based on the various tests w/ the CSM
simulation I showed in Wengen, and will send you a guys a copy once its
finalized. A natural followup would be a similar analysis applying to
the ECHO-G simulation, and we would enjoy collaborating w/ you and Keith
on this. We were also thinking of doing some "mixed signal" analyses,
where the pseudoproxies represent a combinatiiion of temp and precip
(including limiting cases of pure temp and pure precip). This might be a
natural way to incorporate the ECHO-G results. We'll let you know if we
have any trouble w/ format, etc.
thanks again,
mike
Tim Osborn wrote:
> Hi Mike and Scott,
>
> below are details about accessing the ECHO-G data from the SO&P
> web-archive.  There are time series plots of various variables and
> regions that might be useful for a quick overview of what's going on,
> plus the temperature fields (and fields for other variables) can be
> accessed in netCDF format (hope that format is ok, if not I can make a
> conversion for you but that won't be till next week).
>
> I'd like to add to Keith's reasons why we'd like to be involved in the
> outcome of analysis of these data.  The extra reason is that we
> (Keith/me) are free to use these data and thus by extension you can
> too provided we collaborate.  Fidel Gonzalez-Rouco or GKSS aren't yet
> ready to make them completely open access, preferring to consider each
> 3rd party request and decide on that basis.  I did ask Eduardo Zorita
> about making them available for pseudo-proxy challenge after the
> Wengen meeting, but I haven't yet followed up to find out his
> decision.  The bottom line is that they might well make them available
> for you to do your own thing with, but if you are happy to collaborate
> with us then you can definitely use them immediately.
>
> The data are available from here:
>
>
>
> Near the bottom you will find the link to the password-protected model
> data (this includes the time series plots too).  The login details for
> this are:
>
> soapech
> od2004
>
> The 2m air temperature is 3rd in the list of variables.  'Erik' is the
> simulation will all forcings, 'Enat' just has natural forcings through
> to the present.  The easiest way to get all the monthly 2m air
> temperature fields for Erik is to use 'wget'.  There is help for how
> to use 'wget' if you aren't familiar.
>
> The site was designed to be fairly self explanatory; hope you find it
> so.  If not, please just ask.
>
> Best wishes
>
> Tim
>
> At 18:30 05/09/2006, Michael E. Mann wrote:
>
>> sure thing Keith, thanks. and of course, we'll keep you fully in the
>> loop on our findings. I'm copying to Scott, as he's the one who will
>> probably obtain the data from Tim. Thanks again, got to go teach now...
>>
>> mike
>>
>> Keith Briffa wrote:
>>
>>> mike
>>> simply missed the first and been away since second message -
>>> forwarding to Tim to arrange access to these data ( I am assuming
>>> Hans will not mind but best not say anything yet ) we wish to be
>>> involved in this follow up please as it will be a SOAP product and
>>> Tim (especially) and I did stuff to get these data produced and in a
>>> form for dissemination. I am rushing now to Austria for a week .
>>> cheers
>>> Keith
>>>
>>> At 13:51 28/08/2006, you wrote:
>>>
>>>> Keith, I didn't receive a response to my previous inquiry so I'm
>>>> resending. Also copying to Phil in case you haven't been reading
>>>> email for some reason.
>>>>
>>>> We would like to run our RegEM analysis through the ECHO-G
>>>> simulation results. It appears that the results of that simulation
>>>> have been widely disseminated to other groups, and yet they are not
>>>> publically available to our knowledge.
>>>>
>>>> As per your previous suggestion, we would be grateful if we could
>>>> acquire the surface temperature field for the simulation from you
>>>> for some analyses we're doing.
>>>>
>>>> Thanks in advance for any help,
>>>>
>>>> mike
>>>>
>>>> --
>>>> Michael E. Mann
>>>> Associate Professor
>>>> Director, Earth System Science Center (ESSC)
>>>>
>>>> Department of Meteorology              Phone: (814) 863-4075
>>>> 503 Walker Building                    FAX:   (814) 865-3663
>>>> The Pennsylvania State University      email:  mann@psu.edu
>>>> University Park, PA 16802-5013
>>>>
>>>>
>>>
>>>
>>> --
>>> Professor Keith Briffa,
>>> Climatic Research Unit
>>> University of East Anglia
>>> Norwich, NR4 7TJ, U.K.
>>>
>>> Phone: +44-1603-593909
>>> Fax: +44-1603-507784
>>>
>>>
>>
>>
>>
>>
>> --
>> Michael E. Mann
>> Associate Professor
>> Director, Earth System Science Center (ESSC)
>>
>> Department of Meteorology              Phone: (814) 863-4075
>> 503 Walker Building                    FAX:   (814) 865-3663
>> The Pennsylvania State University      email:  mann@psu.edu
>> University Park, PA 16802-5013
>>
>>
>>
>
> Dr Timothy J Osborn, Academic Fellow
> Climatic Research Unit
> School of Environmental Sciences, University of East Anglia
> Norwich  NR4 7TJ, UK
>
> e-mail:   t.osborn@uea.ac.uk
> phone:    +44 1603 592089
> fax:      +44 1603 507784
> web:      ~timo/
> sunclock: ~timo/sunclock.htm
>
> **Norwich -- City for Science:
> **Hosting the BA Festival 2-9 September 2006
>
--
Michael E. Mann
Associate Professor
Director, Earth System Science Center (ESSC)
Department of Meteorology              Phone: (814) 863-4075
503 Walker Building                    FAX:   (814) 865-3663
The Pennsylvania State University      email:  mann@psu.edu
University Park, PA 16802-5013


Keith - thanks for this and the earlier updates. Stefan is not around this week, but
hopefully the others on this email can weight in. My thoughts...
1) We MUST say something about individual years (and by extension the 1998 TAR statement) -
do we support it, or not, and why.
2) a paragraph would be nice, but I doubt we can do that, so..
3) I suggest putting the first sentence that Keith provides below as the last sentence, in
the last (summary) para of 6.6.1.1. To make a stand alone para seems like a bad way to end
the very meaty section.
4) I think the second sentence could be more controversial - I don't think our team feels
it is valid to say, as they did in TAR, that "It is also likely that, in the Northern
Hemisphere,... 1998 was the warmest year" in the last 1000 years. But, it you think about
it for a while, Keith has come up with a clever 2nd sentence (when you insert "Northern
Hemisphere" language as I suggest below). At first, my reaction was leave it out, but it
grows on you, especially if you acknowledge that many readers will want more explicit prose
on the 1998 (2005) issue.
Greater uncertainty associated with proxy-based temperature estimates for individual years
means that it is more difficult to gauge the significance, or precedence, of the extreme
warm years observed in the recent instrumental record. However, there is no new evidence to
challenge the statement made in the TAR that 1998 (or the subsequent near-equivalent 2005)
was likely the warmest of Northern Hemisphere year over the last 1000 years.
5) I strongly agree we can't add anything to the Exec Summary.
6) so, if no one disagrees or edits, I suggest we insert the above 2 sentences to end the
last (summary) para of 6.6.1.1. Or should we make it a separate, last para - see point #3
above why I don't favor that idea as much. But, it's not a clear cut issue.
Thoughts? Thanks all, Peck
Eystein and Peck
I have thought about this and spent some time discussing it with Tim. I have come up
with the following
Greater uncertainty associated with proxy-based temperature estimates for individual
years means that it is more difficult to gauge the significance, or precedence, of the
extreme warm years observed in the recent instrumental record. However, there is no new
evidence to challenge the statement made in the TAR that 1998 (or the subsequent
near-equivalent 2005) was likely the warmest in the last 1000 years.
This should best go after the paragraph that concludes section 6.6.1.1
I believe we might best omit the second sentence of the suggested new paragraph - but
you might consider this too subtle (or negative) then. I think the second sentence is
very subtle also though - because it does not exclude the possibility that the same old
evidence that challenges the veracity of the TAR statement exists now , as then!
I think this could go in the text where suggested , but I think it best NOT to have a
bullet about this point.We need to check exactly what was saidin the TAR . Perhaps a
reference to the Academy Report could also be inserted here?
Anyway, you asked for a straw-man statement for all to argue about so I suggest we send
this to Stefan, David , Betty and whoever else you think.
cheers
Keith
--
Professor Keith Briffa,
Climatic Research Unit
University of East Anglia
Norwich, NR4 7TJ, U.K.
Phone: +44-1603-593909
Fax: +44-1603-507784

--
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


Eystein and Peck
I have thought about this and spent some time discussing it with Tim. I have come up with
the following
Greater uncertainty associated with proxy-based temperature estimates for individual years
means that it is more difficult to gauge the significance, or precedence, of the extreme
warm years observed in the recent instrumental record. However, there is no new evidence to
challenge the statement made in the TAR that 1998 (or the subsequent near-equivalent 2005)
was likely the warmest in the last 1000 years.
This should best go after the paragraph that concludes section 6.6.1.1
I believe we might best omit the second sentence of the suggested new paragraph - but you
might consider this too subtle (or negative) then. I think the second sentence is very
subtle also though - because it does not exclude the possibility that the same old evidence
that challenges the veracity of the TAR statement exists now , as then!
I think this could go in the text where suggested , but I think it best NOT to have a
bullet about this point.We need to check exactly what was saidin the TAR . Perhaps a
reference to the Academy Report could also be inserted here?
Anyway, you asked for a straw-man statement for all to argue about so I suggest we send
this to Stefan, David , Betty and whoever else you think.
cheers
Keith
--
Professor Keith Briffa,
Climatic Research Unit
University of East Anglia
Norwich, NR4 7TJ, U.K.
Phone: +44-1603-593909
Fax: +44-1603-507784
[1]
References
1.


Leaving aside for the moment the resolution issue, the statement should at least be
consistent with our figures. Fig. 6-10 looks like there were years around 1000 AD that
could have been just as warm  - if one wants to make this statement, one needs to expand
the vertical scale in Fig. 6-10 to show that the current warm period is 'warmer'.
Now getting back to the resolution issue: given what we know about the ability to
reconstruct global or NH temperatures in the past - could we really in good conscience say
we have the precision from tree rings and the very sparse other data to make any definitive
statement of this nature (let alone accuracy)? While I appreciate the cleverness of the
second sentence, the problem is everybody will recognize that we are 'being clever' - at
what point does one come out looking aggressively defensive?
I agree that leaving the first sentence as the only sentence suggests that one is somehow
doubting the significance of the recent warm years, which is probably not something we want
to do. What I would suggest is to forget about making 'one year' assessments; what Fig.
6-10 shows is that the recent warm period is highly anomalous with respect to the record of
the last 1000 years. That would be what I think we can safely conclude the last 1000 years
really tells us.
David
At 9:10 AM -0600 9/13/06, Jonathan Overpeck wrote:
Keith - thanks for this and the earlier updates. Stefan is not around this week, but
hopefully the others on this email can weight in. My thoughts...
1) We MUST say something about individual years (and by extension the 1998 TAR
statement) - do we support it, or not, and why.
2) a paragraph would be nice, but I doubt we can do that, so..
3) I suggest putting the first sentence that Keith provides below as the last sentence,
in the last (summary) para of 6.6.1.1. To make a stand alone para seems like a bad way
to end the very meaty section.
4) I think the second sentence could be more controversial - I don't think our team
feels it is valid to say, as they did in TAR, that "It is also likely that, in the
Northern Hemisphere,... 1998 was the warmest year" in the last 1000 years. But, it you
think about it for a while, Keith has come up with a clever 2nd sentence (when you
insert "Northern Hemisphere" language as I suggest below). At first, my reaction was
leave it out, but it grows on you, especially if you acknowledge that many readers will
want more explicit prose on the 1998 (2005) issue.
Greater uncertainty associated with proxy-based temperature estimates for individual
years means that it is more difficult to gauge the significance, or precedence, of the
extreme warm years observed in the recent instrumental record. However, there is no new
evidence to challenge the statement made in the TAR that 1998 (or the subsequent
near-equivalent 2005) was likely the warmest of Northern Hemisphere year over the last
1000 years.
5) I strongly agree we can't add anything to the Exec Summary.
6) so, if no one disagrees or edits, I suggest we insert the above 2 sentences to end
the last (summary) para of 6.6.1.1. Or should we make it a separate, last para - see
point #3 above why I don't favor that idea as much. But, it's not a clear cut issue.
Thoughts? Thanks all, Peck
Eystein and Peck
I have thought about this and spent some time discussing it with Tim. I have come up
with the following
Greater uncertainty associated with proxy-based temperature estimates for individual
years means that it is more difficult to gauge the significance, or precedence, of the
extreme warm years observed in the recent instrumental record. However, there is no new
evidence to challenge the statement made in the TAR that 1998 (or the subsequent
near-equivalent 2005) was likely the warmest in the last 1000 years.
This should best go after the paragraph that concludes section 6.6.1.1
I believe we might best omit the second sentence of the suggested new paragraph - but
you might consider this too subtle (or negative) then. I think the second sentence is
very subtle also though - because it does not exclude the possibility that the same old
evidence that challenges the veracity of the TAR statement exists now , as then!
I think this could go in the text where suggested , but I think it best NOT to have a
bullet about this point.We need to check exactly what was saidin the TAR . Perhaps a
reference to the Academy Report could also be inserted here?
Anyway, you asked for a straw-man statement for all to argue about so I suggest we send
this to Stefan, David , Betty and whoever else you think.
cheers
Keith
--
Professor Keith Briffa,
Climatic Research Unit
University of East Anglia
Norwich, NR4 7TJ, U.K.
Phone: +44-1603-593909
Fax: +44-1603-507784

--
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

--
///////////////////////////////////////////////////////////////////////////
///////////////////////////////////////////////////////////////////////////


Hi all,
My take on this is similar to what Peck wrote.  My suggestion is to write:
Greater uncertainty associated with proxy-based temperature estimates for individual years
means that it is more difficult to gauge the significance, or precedence, of the extreme
warm  individual years observed in the recent instrumental record, such as 1998 and 2005,
in the context of the last millennium.
I  think this is scientifically correct, and in essence means that we, as did the NAS panel
say, feel the TAR statement was not what we would have said. I sympatise with those who say
that it is not likely that any individual  years were warmer, as Stefan has stated, but I
don´t think we have enough data to qualify this on the hemispheric mean.
Best wishes,
Eystein
If this is interpreted as a critisim of the TAR, then I think we
At 14:09 -0600 13-09-06, Jonathan Overpeck wrote:
thanks David - lets see what others think. I agree, that we don't want to be seen as
being too clever or defensive. Note however, that all the TAR said was "likely" the
warmest in the last 1000 years. Our chapter and figs (including 6.10) make it clear that
it is unlikely any multi-decadal period was as warm as the last 50 years. But, that
said, I do feel your are right that our team would not have said what the TAR said about
1998, and thus, we should delete that second sentence.
any other thoughts team?
thx, peck
Leaving aside for the moment the resolution issue, the statement should at least be
consistent with our figures. Fig. 6-10 looks like there were years around 1000 AD that
could have been just as warm  - if one wants to make this statement, one needs to expand
the vertical scale in Fig. 6-10 to show that the current warm period is 'warmer'.
Now getting back to the resolution issue: given what we know about the ability to
reconstruct global or NH temperatures in the past - could we really in good conscience
say we have the precision from tree rings and the very sparse other data to make any
definitive statement of this nature (let alone accuracy)? While I appreciate the
cleverness of the second sentence, the problem is everybody will recognize that we are
'being clever' - at what point does one come out looking aggressively defensive?
I agree that leaving the first sentence as the only sentence suggests that one is
somehow doubting the significance of the recent warm years, which is probably not
something we want to do. What I would suggest is to forget about making 'one year'
assessments; what Fig. 6-10 shows is that the recent warm period is highly anomalous
with respect to the record of the last 1000 years. That would be what I think we can
safely conclude the last 1000 years really tells us.
David
At 9:10 AM -0600 9/13/06, Jonathan Overpeck wrote:
Keith - thanks for this and the earlier updates. Stefan is not around this week, but
hopefully the others on this email can weight in. My thoughts...
1) We MUST say something about individual years (and by extension the 1998 TAR
statement) - do we support it, or not, and why.
2) a paragraph would be nice, but I doubt we can do that, so..
3) I suggest putting the first sentence that Keith provides below as the last sentence,
in the last (summary) para of 6.6.1.1. To make a stand alone para seems like a bad way
to end the very meaty section.
4) I think the second sentence could be more controversial - I don't think our team
feels it is valid to say, as they did in TAR, that "It is also likely that, in the
Northern Hemisphere,... 1998 was the warmest year" in the last 1000 years. But, it you
think about it for a while, Keith has come up with a clever 2nd sentence (when you
insert "Northern Hemisphere" language as I suggest below). At first, my reaction was
leave it out, but it grows on you, especially if you acknowledge that many readers will
want more explicit prose on the 1998 (2005) issue.
Greater uncertainty associated with proxy-based temperature estimates for individual
years means that it is more difficult to gauge the significance, or precedence, of the
extreme warm years observed in the recent instrumental record. However, there is no new
evidence to challenge the statement made in the TAR that 1998 (or the subsequent
near-equivalent 2005) was likely the warmest of Northern Hemisphere year over the last
1000 years.
5) I strongly agree we can't add anything to the Exec Summary.
6) so, if no one disagrees or edits, I suggest we insert the above 2 sentences to end
the last (summary) para of 6.6.1.1. Or should we make it a separate, last para - see
point #3 above why I don't favor that idea as much. But, it's not a clear cut issue.
Thoughts? Thanks all, Peck
Eystein and Peck
I have thought about this and spent some time discussing it with Tim. I have come up
with the following
Greater uncertainty associated with proxy-based temperature estimates for individual
years means that it is more difficult to gauge the significance, or precedence, of the
extreme warm years observed in the recent instrumental record. However, there is no new
evidence to challenge the statement made in the TAR that 1998 (or the subsequent
near-equivalent 2005) was likely the warmest in the last 1000 years.
This should best go after the paragraph that concludes section 6.6.1.1
I believe we might best omit the second sentence of the suggested new paragraph - but
you might consider this too subtle (or negative) then. I think the second sentence is
very subtle also though - because it does not exclude the possibility that the same old
evidence that challenges the veracity of the TAR statement exists now , as then!
I think this could go in the text where suggested , but I think it best NOT to have a
bullet about this point.We need to check exactly what was saidin the TAR . Perhaps a
reference to the Academy Report could also be inserted here?
Anyway, you asked for a straw-man statement for all to argue about so I suggest we send
this to Stefan, David , Betty and whoever else you think.
cheers
Keith
--
Professor Keith Briffa,
Climatic Research Unit
University of East Anglia
Norwich, NR4 7TJ, U.K.
Phone: +44-1603-593909
Fax: +44-1603-507784

--
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

--
///////////////////////////////////////////////////////////////////////////
///////////////////////////////////////////////////////////////////////////
--
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

--
______________________________________________________________
Eystein Jansen
Professor/Director
Bjerknes Centre for Climate Research and
Dep. of Earth Science, Univ. of Bergen
Allégaten 55
N-5007 Bergen
NORWAY
e-mail: eystein.jansen@geo.uib.no
Phone:    +47-55-583491  -  Home: +47-55-910661
Fax:       +47-55-584330


Thanks Keith, Tim and Fortunat for your input.
We'll go with what we have then - Eystein's
suggestion minus the second "individual".
Eystein and Øyvind - just want to double check
that you've deleted that 2nd "individual" in the
all important 1998 sentence??
Thanks, Peck
>I do not disagree either - in fact I preferred
>not to make the "too clever" second statement in
>my "straw man" as I said at the time. If this is
>the consensus (and I believe it is the
>scientifically correct one) then I would be
>happy with Eystein's sentence. The worry is that
>we have inserted this late with no refereeing
>and no justification in the text. I would also
>suggest dropping the second "!individual" in the
>sentence.
>
>At 10:50 15/09/2006, Fortunat Joos wrote:
>>Hi,
>>
>>I support Eystein's suggestion and agree with David.
>>
>>If there is not sufficient evidence to support
>>or dismis claims whether 1998 or
>>2005 was the warmest year of the millennium than we should indeed say so.
>>It is the nature and the strenght of the IPCC
>>process that points from the TAR
>>and earlier reports get reconsidered and
>>reassessed. It is normal that earlier
>>statements get revised. Often statements can be strenghtened, but sometimes
>>statements can not be supported anymore. Our job is to present the current
>>understanding of science as balanced as possible.
>>
>>With best wishes,
>>
>>Fortunat
>>
>>Quoting Eystein Jansen
:
>>
>>>  Hi all,
>>>  My take on this is similar to what Peck wrote.  My suggestion is to write:
>>>
>>>  Greater uncertainty associated with proxy-based
>>>  temperature estimates for individual years means
>>>  that it is more difficult to gauge the
>>>  significance, or precedence, of the extreme warm
>>>  individual years observed in the recent
>>>  instrumental record, such as 1998 and 2005, in
>>>  the context of the last millennium.
>>>
>>>  I  think this is scientifically correct, and in
>>>  essence means that we, as did the NAS panel say,
>>>  feel the TAR statement was not what we would have
>>>  said. I sympatise with those who say that it is
>>>  not likely that any individual  years were
>>>  warmer, as Stefan has stated, but I don´t think
>>>  we have enough data to qualify this on the
>>>  hemispheric mean.
>>>
>>>  Best wishes,
>>>  Eystein
>>>
>>>
>>>  If this is interpreted as a critisim of the TAR, then I think we
>>>  At 14:09 -0600 13-09-06, Jonathan Overpeck wrote:
>>>  >thanks David - lets see what others think. I
>>>  >agree, that we don't want to be seen as being
>>>  >too clever or defensive. Note however, that all
>>>  >the TAR said was "likely" the warmest in the
>>>  >last 1000 years. Our chapter and figs (including
>>>  >6.10) make it clear that it is unlikely any
>>>  >multi-decadal period was as warm as the last 50
>>>  >years. But, that said, I do feel your are right
>>>  >that our team would not have said what the TAR
>>>  >said about 1998, and thus, we should delete that
>>>  >second sentence.
>>>  >
>>>  >any other thoughts team?
>>>  >
>>>  >thx, peck
>>>  >
>>>  >
>>>  >>Leaving aside for the moment the resolution
>>>  >>issue, the statement should at least be
>>>  >>consistent with our figures. Fig. 6-10 looks
>>>  >>like there were years around 1000 AD that could
>>>  >>have been just as warm  - if one wants to make
>>>  >>this statement, one needs to expand the
>>>  >>vertical scale in Fig. 6-10 to show that the
>>>  >>current warm period is 'warmer'.
>>>  >>
>>>  >>Now getting back to the resolution issue: given
>>>  >>what we know about the ability to reconstruct
>>>  >>global or NH temperatures in the past - could
>>>  >>we really in good conscience say we have the
>>>  >>precision from tree rings and the very sparse
>>>  >>other data to make any definitive statement of
>>>  >>this nature (let alone accuracy)? While I
>>>  >>appreciate the cleverness of the second
>>>  >>sentence, the problem is everybody will
>>>  >>recognize that we are 'being clever' - at what
>>  > >>point does one come out looking aggressively
>>>  >>defensive?
>>>  >>
>>>  >>  I agree that leaving the first sentence as the
>>>  >>only sentence suggests that one is somehow
>>>  >>doubting the significance of the recent warm
>>>  >>years, which is probably not something we want
>>>  >>to do. What I would suggest is to forget about
>>>  >>making 'one year' assessments; what Fig. 6-10
>>>  >>shows is that the recent warm period is highly
>>>  >>anomalous with respect to the record of the
>>>  >>last 1000 years. That would be what I think we
>>>  >>can safely conclude the last 1000 years really
>>>  >>tells us.
>>>  >>
>>>  >>David
>>>  >>
>>>  >>At 9:10 AM -0600 9/13/06, Jonathan Overpeck wrote:
>>>  >>>Keith - thanks for this and the earlier
>>>  >>>updates. Stefan is not around this week, but
>>>  >>>hopefully the others on this email can weight
>>>  >>>in. My thoughts...
>>>  >>>
>>>  >>>1) We MUST say something about individual
>>>  >>>years (and by extension the 1998 TAR
>>>  >>>statement) - do we support it, or not, and why.
>>>  >>>
>>>  >>>2) a paragraph would be nice, but I doubt we can do that, so..
>>>  >>>
>>>  >>>3) I suggest putting the first sentence that
>>>  >>>Keith provides below as the last sentence, in
>>>  >>>the last (summary) para of 6.6.1.1. To make a
>>>  >>>stand alone para seems like a bad way to end
>>>  >>>the very meaty section.
>>>  >>>
>>>  >>>4) I think the second sentence could be more
>>>  >>>controversial - I don't think our team feels
>>>  >>>it is valid to say, as they did in TAR, that
>>>  >>>"It is also likely that, in the Northern
>>>  >>>Hemisphere,... 1998 was the warmest year" in
>>>  >>>the last 1000 years. But, it you think about
>>>  >>>it for a while, Keith has come up with a
>>>  >>>clever 2nd sentence (when you insert "Northern
>>>  >>>Hemisphere" language as I suggest below). At
>>>  >>>first, my reaction was leave it out, but it
>>>  >>>grows on you, especially if you acknowledge
>>>  >>>that many readers will want more explicit
>>>  >>>prose on the 1998 (2005) issue.
>>>  >>>
>>>  >>>Greater uncertainty associated with
>>>  >>>proxy-based temperature estimates for
>>>  >>>individual years means that it is more
>>>  >>>difficult to gauge the significance, or
>>>  >>>precedence, of the extreme warm years observed
>>>  >>>in the recent instrumental record. However,
>>>  >>>there is no new evidence to challenge the
>>>  >>>statement made in the TAR that 1998 (or the
>>>  >>>subsequent near-equivalent 2005) was likely
>>>  >>>the warmest of Northern Hemisphere year over
>>>  >>>the last 1000 years.
>>>  >>>
>>>  >>>5) I strongly agree we can't add anything to the Exec Summary.
>>>  >>>
>>>  >>>6) so, if no one disagrees or edits, I suggest
>>>  >>>we insert the above 2 sentences to end the
>>>  >>>last (summary) para of 6.6.1.1. Or should we
>>>  >>>make it a separate, last para - see point #3
>>>  >>>above why I don't favor that idea as much.
>>>  >>>But, it's not a clear cut issue.
>>>  >>>
>>>  >>>Thoughts? Thanks all, Peck
>>>  >>>
>>>  >>>
>>>  >>>>Eystein and Peck
>>>  >>>>I have thought about this and spent some time
>>>  >>>>discussing it with Tim. I have come up with
>>>  >>>>the following
>>>  >>>>
>>>  >>>>Greater uncertainty associated with
>>>  >>>>proxy-based temperature estimates for
>>>  >>>>individual years means that it is more
>>>  >>>>difficult to gauge the significance, or
>>>  >>>>precedence, of the extreme warm years
>>>  >>>>observed in the recent instrumental record.
>>>  >>>>However, there is no new evidence to
>>>  >>>>challenge the statement made in the TAR that
>>>  >>>>1998 (or the subsequent near-equivalent 2005)
>>>  >>>>was likely the warmest in the last 1000 years.
>>>  >>>>
>>>  >>>>This should best go after the paragraph that concludes section 6.6.1.1
>>>  >>>>
>>>  >>>>I believe we might best omit the second
>>>  >>>>sentence of the suggested new paragraph - but
>>>  >>>>you might consider this too subtle (or
>>>  >>>>negative) then. I think the second sentence
>>>  >>>>is very subtle also though - because it does
>>>  >>>>not exclude the possibility that the same old
>>>  >>>>evidence that challenges the veracity of the
>>>  >>>>TAR statement exists now , as then!
>>>  >>>>I think this could go in the text where
>>>  >>>>suggested , but I think it best NOT to have a
>>>  >>>>bullet about this point.We need to check
>>>  >>>>exactly what was saidin the TAR . Perhaps a
>>  > >>>>reference to the Academy Report could also be
>>>  >>>>inserted here?
>>>  >>>>
>>>  >>>>Anyway, you asked for a straw-man statement
>>>  >>>>for all to argue about so I suggest we send
>>>  >>>>this to Stefan, David , Betty and whoever
>>>  >>>>else you think.
>>>  >>>>cheers
>>>  >>>>Keith
>>>  >>>>
>>>  >>>>--
>>>  >>>>Professor Keith Briffa,
>>>  >>>>Climatic Research Unit
>>>  >>>>University of East Anglia
>>>  >>>>Norwich, NR4 7TJ, U.K.
>>>  >>>>
>>>  >>>>Phone: +44-1603-593909
>>>  >>>>Fax: +44-1603-507784
>>>  >>>>
>>>  >>>>
>>>  >>>
>>>  >>>
>>>  >>>--
>>>  >>>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
>>>  >>>
>>>  >>>
>>>  >>
>>>  >>
>>>  >>--
>>>  >>////////////////////////////////////////////
>>>///////////////////////////////
>>>  >>
>>>  >>////////////////////////////////////////////
>>>///////////////////////////////
>>>  >
>>>  >
>>>  >--
>>>  >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
>>>  >
>>>  >
>>>
>>>
>>>  --
>>>  ______________________________________________________________
>>>  Eystein Jansen
>>>  Professor/Director
>>>  Bjerknes Centre for Climate Research and
>>>  Dep. of Earth Science, Univ. of Bergen
>>>  Allégaten 55
>>>  N-5007 Bergen
>>>  NORWAY
>>>  e-mail: eystein.jansen@geo.uib.no
>>>  Phone:        +47-55-583491  -  Home: +47-55-910661
>>>  Fax:  +47-55-584330
>>
>>
>>--
>>   Climate and Environmental Physics
>>   Sidlerstr. 5, CH-3012 Bern
>>   Phone:    ++41(0)31 631 44 61      Fax:      ++41(0)31 631 87 42
>>   Internet: ~joos/
>
>--
>Professor Keith Briffa,
>Climatic Research Unit
>University of East Anglia
>Norwich, NR4 7TJ, U.K.
>
>Phone: +44-1603-593909
>Fax: +44-1603-507784
>
>
--
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


Hi Oyvind,
I was off work yesterday so I couldn't check the tables until today.  Keith and I have
spotted some corrections that need to be made, some my mistakes and some due to other
changes.  Sorry!  Anyway all are shown as tracked changes (plus explanation comments) in
the attached file.  Hope this is all clear and ok.
Cheers
Tim
At 17:02 13/09/2006, Øyvind Paasche wrote:
tim - that's very good, the minor error in box fig.1 is now corrected. I think the lines
in fig.6.10 and 6.14 are sufficiently thick so if its up to me we'll leave them as they
are. I believe that all the figures are incorporated into the Word file the same way and
I can't see any big difference between 6.10 and 6.14. TSU have eps formats of all the
figures and in the end they will probably use an entirely different program than Word to
construct the report, so I guess there's nothing to worry about.
Anyway, I have cleaned the standing version of the tables (attached) and if you (and/or
Keith) could go through them a last time and check that everything is as it should be
that would be nice. I have one question concerning one of the refs in table 6.2: Does
Bertrand et al., 2002b correspond to
Bertrand, C., M.F. Loutre, M. Crucifix, and A. Berger, 2002b: Climate of the last
millennium: a sensitivity study. Tellus Series a-Dynamic Meteorology and Oceanography,
54(3), 221-244.
Cheers,
Øyvind
Hi,
I've checked that the figures and captions are the final versions and they are all
correct for figures 6.10-6.14.
I've also checked Box 6.4, Figure 1 and here there is an error with the caption.  The
caption ends with the reference period which currently states '...the period 800-1995."
I got this wrong.  The correct statement is "...the period 1001-1980."
Sorry about that (it was a mistake carried over from our earlier use of the figure from
Osborn and Briffa, 2006, Science: for that paper we did use 800-1995).
Were you also after a check of the image quality?  The figures I'm involved with all
look pretty good, except that 6.10 is a bit blurry or lower quality.  Was it inserted
into Word in a different way to the others that might have degraded the image?  Also, I
wonder whether I should make the lines on Figure 6.10(b) and/or Figure 6.14(b) any
thicker?  Please let me know if you want me to do this.
Cheers
Tim
At 01:46 13/09/2006, Jonathan Overpeck wrote:
Hi all - We're editing main text, and we think we're close to the right length without
having to make significant cuts beyond what you've seen already - it's mostly down to
editing for consistent style and clarity. That's good news.
Øyvind recently sent (working very late over their) the attached figs and caption files
(being sent in two files to keep each half under 10 Mb), and rather than Peck trying to
figure out if it's all perfect, we're sending to YOU look at your figures and captions
to make sure they are the most up-to-date versions. Thanks! It's a challenge to make
sure we have all the most recent pieces, although we're betting that we're doing ok.
Tomorrow (I hope - thanks Øyvind!) we'll send tables - hoping Tim, Keith, and Fortunat
will be waiting to comment/edit if needed.
We're in much better shape than last cycles thanks to all your hard work - hope we can
make this last bit easy for you. We appreciate you working fast when we send material.
Thanks, Peck and Eystein
--
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
[1]
[2]
Dr Timothy J Osborn, Academic Fellow
Climatic Research Unit
School of Environmental Sciences, University of East Anglia
Norwich  NR4 7TJ, UK
e-mail:   t.osborn@uea.ac.uk
phone:    +44 1603 592089
fax:      +44 1603 507784
web:      [3]~timo/
sunclock: [4]~timo/sunclock.htm
**Norwich -- City for Science:
**Hosting the BA Festival 2-9 September 2006
--
Dr. Øyvind Paasche
Bjerknes Centre for Climate Research/
Department of Earth Science
University of Bergen
Allé gt. 55
N-5007, Bergen
Norway
Phone direct: +47 55583297
Cell phone: +47 93048919
E-mail: oyvind.paasche@bjerknes.uib.no
References
1.
2.
3. ~timo/
4. ~timo/sunclock.htm


Hi Gabi - we do loose quite a bit (e.g., boreholes and other proxies)
back beyond 500, so that's why we drew the "very likely" line there.
But, we did stay as strong as the TAR back 1300, so that was our
compromise on certainty. I believe the forcing series also start to
get more uncertain pretty fast back beyond even 400 years ago, but
I'm pretty impressed with the match between simulated and observed NH
climate back ca. 700 years (e.g., our Figs 6.13 and 6.14). Thus, I
bet you are right that we know back to 700 pretty well, but not well
enough to go with "very likely" in the all important chap 6 bullet.
Not sure this helps, but we do need to pay attention as we do the SPM
to get the right balance.
I'll cc to Keith in case he wants to chime in, which would be appreciated.
thanks, peck
>p.s. hope you are all recovered etc!
>I have one chapter question: We were waffling back and forth if we
>SHOULD go with the chapter 6
>assessment on the last 500 being better reconstructed than say last
>700, but in the end, we stuck with
>last 700 because some results rely on using a long timehorizon to
>separate like ghg and solar signals.
>To say that very likely a substantial fraction of the variance on
>those records is externally forced (nother
>words, detectable external signals in reconstructions).
>Does this seem ok to you? In the SPM session we had some waffling
>about 5 vs 7 centuries.
>
>Gabi
>
>Jonathan Overpeck wrote:
--
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


I asked Tom about it, he says (but I realize he is one sample of the
volcano enthusiasts) it could
have been El Chichon, the eruption seems to be huge, but there is
concerns that different physics
would apply to such a large eruption making it cause different climate
impacts (he cites a paper
for that that I promplty forgot).
I am always slightly nervous about the fact that this one doesnt show up
in the data, and wondering
if there is a sliver of circularity, but I think results like my
detection stuff and probably also EPOCH
stuff (I could try) are quite robust to missing an eruption, even a biggie.
Greetings everybody!
Gabi
Keith Briffa wrote:
> Hi everyone - just been at a meeting all day so just seen this . I
> agree with Eystein et al . so no problems . Interested to know what
> you mean Gabi about the 1256 eruption - we have been looking at the
> empirical evidence for a contemporaneous cooling with ambiguous results
> cheers
> Keith
>
>
>
> At 20:16 19/09/2006, Eystein Jansen wrote:
>
>> Hi Gabi,
>> this is fine with me and does not seem to contradict Ch6.
>> Eystein
>>
>>
>>
>>
>> At 15:06 -0400 19-09-06, Gabi Hegerl wrote:
>>
>>> SOunds good - since forcing and temperature reconstrucitons are
>>> independent,
>>> I think it was defensible to make a statement about role of forced
>>> response 700 yrs back in Ch9.
>>> Is it ok to keep 700 yrs about significant externally forced
>>> component in SPM?
>>> Susan is finetuning that bullet right now so thats why i thought it
>>> would be good to know if you guys are
>>> happy.
>>> We justified ch9's assessment based on your figure 6.13 showing
>>> model and recon agreement, and on few detection
>>> studies and some qualitatative agreement studies all saying the
>>> agreement is not spurious.
>>> One issue going beyond further is  1256 eruption, which is not that
>>> well understood,
>>> so it gets a bit dicey beyond I think!
>>>
>>> Gabi
>>>
>>> Jonathan Overpeck wrote:
>>>
>>>> Hi Gabi - we do loose quite a bit (e.g., boreholes and other
>>>> proxies) back beyond 500, so that's why we drew the "very likely"
>>>> line there. But, we did stay as strong as the TAR back 1300, so
>>>> that was our compromise on certainty. I believe the forcing series
>>>> also start to get more uncertain pretty fast back beyond even 400
>>>> years ago, but I'm pretty impressed with the match between
>>>> simulated and observed NH climate back ca. 700 years (e.g., our
>>>> Figs 6.13 and 6.14). Thus, I bet you are right that we know back to
>>>> 700 pretty well, but not well enough to go with "very likely" in
>>>> the all important chap 6 bullet.
>>>>
>>>> Not sure this helps, but we do need to pay attention as we do the
>>>> SPM to get the right balance.
>>>>
>>>> I'll cc to Keith in case he wants to chime in, which would be
>>>> appreciated.
>>>>
>>>> thanks, peck
>>>>
>>>>> p.s. hope you are all recovered etc!
>>>>> I have one chapter question: We were waffling back and forth if we
>>>>> SHOULD go with the chapter 6
>>>>> assessment on the last 500 being better reconstructed than say
>>>>> last 700, but in the end, we stuck with
>>>>> last 700 because some results rely on using a long timehorizon to
>>>>> separate like ghg and solar signals.
>>>>> To say that very likely a substantial fraction of the variance on
>>>>> those records is externally forced (nother
>>>>> words, detectable external signals in reconstructions).
>>>>> Does this seem ok to you? In the SPM session we had some waffling
>>>>> about 5 vs 7 centuries.
>>>>>
>>>>> Gabi
>>>>>
>>>>> Jonathan Overpeck wrote:
>>>>
>>>>
>>>
>>> --
>>> ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
>>> Gabriele Hegerl Division of Earth and Ocean Sciences, Nicholas
>>> School for the Environment and Earth Sciences,
>>> Box 90227
>>> Duke University, Durham NC 27708
>>> Ph: 919 684 6167, fax 684 5833  email: hegerl@duke.edu,
>>>
>>
>>
>>
>> --
>> ______________________________________________________________
>> Eystein Jansen
>> Professor/Director
>> Bjerknes Centre for Climate Research and
>> Dep. of Earth Science, Univ. of Bergen
>> Allégaten 55
>> N-5007 Bergen
>> NORWAY
>> e-mail: eystein.jansen@geo.uib.no
>> Phone:  +47-55-583491  -  Home: +47-55-910661
>> Fax:    +47-55-584330
>
>
> --
> Professor Keith Briffa,
> Climatic Research Unit
> University of East Anglia
> Norwich, NR4 7TJ, U.K.
>
> Phone: +44-1603-593909
> Fax: +44-1603-507784
>
>
>
--
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Gabriele Hegerl
Division of Earth and Ocean Sciences,
Nicholas School for the Environment and Earth Sciences,
Box 90227
Duke University, Durham NC 27708
Ph: 919 684 6167, fax 684 5833
email: hegerl@duke.edu,


Hi Tim
I've found some 'communicating cc' ref's which I've attached - nothing too
hard going! Futerra's 'rules of the game' is a good intro to what climate
change communicators should be working towards in terms of best practice.
Sophie's poster is a summary of the main findings of her PhD research from a
couple of years back in ENV, and is a message that some NGOs in particular
would still do well to heed! Finally, the communicating CC document is an
outline of Defra's recent initiative, as followed on from Futerra's
consultancy work.
PhD stuff: at the last panel meeting, we agreed to meet again in early
October. However, I think this meeting would best be delayed until we know
exactly what info we can obtain for the expert elicitation as r.e. ice
extent maps, time series etc.
I forwarded on the email from Xiangdong Zhang a few days ago - he's happy to
give me some plots showing 2-D distribution of sea ice concentrations around
2050 and also animations from 1900-2100 under the A1B scenario.
How is the ice modelling going? Do you think you'd be able to get some plots
say by w/c 9th Oct so we could talk about them in the meeting?
Cheers
Saffron
Attachment Converted: "c:\documents and settings\tim osborn\my documents\eudora\attach\communicating_climate_change.pdf"
Attachment Converted: "c:\documents and settings\tim osborn\my documents\eudora\attach\POSTER SNC.pdf"
Attachment Converted: "c:\documents and settings\tim osborn\my documents\eudora\attach\RulesOfTheGame.pdf"


Hi Keith and Eystein - thanks for the timely and helpful (very) feedback, Keith. Your
suggestions for 4 and 5 seem fine, and I wonder only about 6. I too am not sure where the
final clause came from, but I'll guess it was a suggestion of Stefan's that then stood the
text of time. In the spirit of trying hard not to change the meaning of bullets in the ES
from what the LA team agreed to in Bergen, what about changing this clause in the ES to
read "natural recovery", i.e.:
and it is very unlikely that this warming was merely a natural recovery from the pre-20th
century cold period."
This takes away the ambiguity, and does serve to address a widely held misconception
outside of our community - or at least to phrase the issue in terms that some might find
more useful.
If we keep this phrase, then I would suggest restating the entire ES sentence at the end of
6.6.3.
Is this ok? Again, I'm motivated by our team agreement - I do think we could delete this
phrase since it's more repetitive than new meaning, but would rather not unless it really
does not work. Personally, I like it as modified above, because it hammers the important
point from a slightly different perspective - one that seems to be on the minds of the
public still.
Thanks, both, for letting me know what you think fast.
best, peck
Hi Peck and Eystein
In response to Points 4-6
4.  Add the following after past 1300 years.    on line 13 page Y-33
"Considering the recent instrumental and longer proxy evidence together, it is very
likely that average Northern Hemisphere temperatures during the second half of the 20th
century were warmer than any other 50-year period in the last 500 years. "
Do not put anything in Box 6.4 which is written frolm the reverse perspective - evidence
of medieval period not good enough to say warmer than now. Also confuses statements
about 500 years and longer (1000 year ) Medieval ,time.
5. The person who says this has not read the text - see lines 28-33 on Y-32 where I
think this is well covered.
6.  If you read the text on lines 1-10 of PAGE Y-38 I think this meaning is clearly
conveyed. It is not in the same words -but easily supports the ES statement.
HOWEVER, I do not like the last part of the statement (and not sure where this came
from) because it is ambiguous and anyway implied by prior statement. I strongly urge you
to remove the section
"and it is very unlikely that this warming was merely a recovery from the pre-20th
century cold period."
These would sort things out I believe
cheers
Keith
At 19:26 05/10/2006, you wrote:
Hi Keith and Tim - we just got the attached consistency feedback doc from the TSU, and
I've added my thoughts in red. We need your feedback on items 4-6 REALLY FAST. Tim, if
Keith's not around to help, please do the job - the TSU has zero time to give us.
I think the solutions to #5 and 6 are easy as I suggested (although I don't have
confirmation from Susan or Martin that we can just do as I suggest, but it seems logical
to me - if you can suggest an even better solution, pls do.
I'll send the official chap 6 final draft text next - at least as it stands today.
thanks for dealing with this, perhaps before you go to sleep this evening.
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

--
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


thanks very much Christoph, that's perfect.
regards,
mike
Christoph Kull wrote:
Hi Mike,
If the EOS-piece is not already submitted...
Below a paragraph we propose to use for the short description of the second
project.
"Furthermore, the participants identified the need and a major opportunity
to improve the quality and value of climate reconstructions. Therefore, a
workshop is planned to assess uncertainties in proxies in a coherent way and
to develop strategies for future collection and integration of proxy data
from key regions. The workshop will focus on climate proxies that have
decadal or better temporal resolution and will involve the world data
centers."
Thanks a lot! Best wishes!
Christoph
On 30.09.2006 19:56, "Michael E. Mann" [1]
wrote:
Dear Keith/Phil/Thorsten/Christoph/Heinz,
Sorry this took Eos so long. No surprises here. A few minor revisions and it
should be ready for publication. Please see attached revised version and
response to reviewers. I've highlighted in yellow one place in the draft where
I could use some input from someone who is better qualified to elaborate on
the details of the 2nd project mentioned. Other than that, let me know if you
see any need for any additional changes.
Will resubmit once I've heard back from everyone.
best regards,
mike
--
Michael E. Mann
Associate Professor
Director, Earth System Science Center (ESSC)
Department of Meteorology              Phone: (814) 863-4075
503 Walker Building                    FAX:   (814) 865-3663
The Pennsylvania State University      email:  [2]mann@psu.edu
University Park, PA 16802-5013
[3]
References
1. mailto:mann@meteo.psu.edu
2. mailto:mann@psu.edu
3.